Mobility assistance devices

Abstract

To provide mobility devices, and more specifically, control systems for vehicles that have heightened requirements for safety and reliability.SOLUTION: There is provided a powered balancing mobility device that can provide a user with the ability to safely navigate expected environments of daily living including the ability to maneuver in confined spaces, to climb curbs, stairs and other obstacles, and to travel safely and comfortably in vehicles. The mobility device can provide elevated, balanced travel.SELECTED DRAWING: Figure 27D

Description

[Technical Field]

[0001] The present teachings relate generally to mobility assistance devices, and more particularly to control systems for vehicles with enhanced safety and reliability requirements. [Background technology]

[0002] A wide range of devices and methods are known for transporting human subjects with physical disabilities. The design of these devices generally requires compromises to accommodate the user's physical limitations. When stability is deemed essential, the relative ease of locomotion may be compromised. When transporting a disabled person or other person up and down stairs is deemed essential, convenient locomotion along areas that do not include stairs may be compromised. Devices that achieve features that may be useful to disabled users may be complex, heavy, and difficult for ordinary locomotion.

[0003] Some systems provide for travel in an upright position, while others provide for climbing stairs, some systems can provide for anomaly detection and maneuvering once an anomaly is detected, while others provide for transporting a user over irregular terrain.

[0004] A control system for an actively stabilized personal vehicle or mobility assist device can maintain the stability of the mobility assist device by continuously sensing the orientation of the mobility assist device, determining corrective actions, maintaining stability, and commanding the wheel motors to take corrective actions. Currently, if the mobility assist device loses its ability to maintain stability, such as through component failure, the user may experience discomfort, particularly upon sudden loss of balance. Additionally, users may desire improved safety features and more control over the mobility assist device's response to unstable situations.

[0005] What is needed is a reliable, lightweight, and stable mobility assist device that includes automatic response capabilities to situations commonly experienced by users with disabilities, such as, but not limited to, positional obstacles, slippery surfaces, tip-over conditions, and component failure. What is further needed is a mobility assist device with long-life redundant batteries, ergonomically positioned and shock-cushioned caster wheel assemblies, and entry / exit management bumpers. What is still further needed is a mobility assist device that includes automatic mode transitions, improved performance over other mobility assist vehicles, remote control, and vehicle locking mechanisms. The mobility assist device should also include foreign object seals and grade management, cabled charging ports, and increased payload capacity over the prior art. Summary of the Invention [Means for solving the problem]

[0006] A motorized balancing mobility assist device of the present teachings can include, without limitation, a base assembly that processes movement commands for the mobility assist device, and at least one cluster assembly operably coupled to the base assembly, the at least one cluster assembly operably coupled to a plurality of wheels that support the base assembly, and the plurality of wheels and the at least one cluster assembly that move the mobility assist device based at least on the processed movement commands. The mobility assist device can include an active stabilization processor that estimates a center of gravity of the mobility assist device, the active stabilization processor estimating at least one value associated with the mobility assist device that is required to maintain balance of the mobility assist device based on the estimated center of gravity. The base processor can actively balance the mobility assist device on at least two of the plurality of wheels based at least on the at least one value. The base assembly may optionally include a redundant motor for moving the at least one cluster assembly and the plurality of wheels, a redundant sensor for sensing sensor data from the redundant motor and the at least one cluster assembly, and a redundant processor executing within the base assembly, the redundant processor selecting information from the sensor data, the selection based on a match of the sensor data between the redundant processors, and the redundant processor processing movement commands based at least on the selected information.

[0007] The powered balance transfer assist device can optionally include an anti-tip controller that stabilizes the mobility assist device based on a stabilization factor, the anti-tip controller executing commands including calculating a stabilization metric, calculating a stabilization factor, determining movement command information required to process the movement command, and if the stabilization metric indicates stabilization is required, processing the movement command based on the movement command information and the stabilization factor. The powered balance transfer assist device can optionally include a stair-climbing failsafe that forces the mobility assist device to safely tip over if stability is lost during stair climbing. The motorized balance mobility assist device optionally can include a caster wheel assembly operably coupled to the base assembly; a linear acceleration processor that calculates a mobility assist device acceleration of the mobility assist device based at least on wheel speeds, the linear acceleration processor calculating an inertial sensor acceleration of an inertial sensor mounted on the mobility assist device based at least on sensor data from the inertial sensor; a traction control processor that calculates a difference between the mobility assist device acceleration and the inertial sensor acceleration, the traction control processor comparing the difference to a preselected threshold; and a wheel / cluster command processor that commands at least one cluster assembly to lower at least one of the plurality of wheel and caster assemblies to the ground based at least on the comparison.

[0008] The infrastructure processor can optionally use field weakening to provide bursts of speed to motors associated with at least one cluster assembly and a plurality of wheels. The infrastructure processor can optionally estimate the center of gravity of the mobility assist device by (1) measuring data including a pitch angle required to maintain balance of the mobility assist device at a preselected position of the at least one wheel cluster and a preselected position of the seat, (2) moving the mobility assist device / user pair to a plurality of points and repeating step (1) at each of the plurality of points, (3) verifying that the measured data is within preselected limits, and (4) generating a set of calibration coefficients to establish a center of gravity during operation of the mobility assist device, the calibration coefficients being based at least on the verified measurement data. The infrastructure processor can optionally include a closed-loop controller that maintains stability of the mobility assist device, the closed-loop controller automatically slowing forward motion and accelerating backward motion under preselected conditions, the preselected conditions being based on the pitch angle of the mobility assist device and the center of gravity of the mobility assist device.

[0009] The motorized balance mobility assist device can optionally include an all-terrain wheel pair including an inner wheel having at least one locking means accessible by an operator of the mobility assist device while the mobility assist device is in operation, the inner wheel having the at least one retaining means, and the all-terrain wheel pair includes an outer wheel having an attachment base, the attachment base housing the at least one locking means and the at least one retaining means, operable by the operator to connect the inner wheel to the outer wheel while the mobility assist device is in operation.

[0010] The motorized balance movement assist device may optionally include a base processor board including at least one inertial sensor, the at least one inertial sensor being mounted on the inertial sensor board, the at least one inertial sensor board being flexibly coupled to the base processor board, the at least one inertial sensor board being separate from the base processor board, and the at least one inertial sensor being calibrated in isolation from the base processor board. The motorized balance movement assist device may optionally include at least one inertial sensor including a gyroscope and an accelerometer.

[0011] The infrastructure processor can optionally include a mobility assistance device wireless processor that enables communication with external applications electronically remote from the mobility assistance device, the mobility assistance device wireless processor receives and decodes incoming messages from wireless radio waves, and the infrastructure processor controls the mobility assistance device based on at least one decoded incoming message. The infrastructure processor can optionally include a secure wireless communication system that includes data obfuscation and challenge / response authentication.

[0012] The motorized balance and mobility assist device may optionally include an indirect heat dissipation path between the base processor board and the chassis of the mobility assist device. The motorized balance and mobility assist device may optionally include a seat support assembly that allows connection of multiple seat types to the base assembly, the base assembly having a seat position sensor that provides seat position data to the base processor. The seat support assembly optionally includes a seat lift arm that lifts the seat and a shaft operably coupled to the seat lift arm, the shaft rotation being measured by the seat position sensor, the shaft rotating through <90°, the shaft coupled to the seat position sensor by a single stage gear train. And , the seat position sensor can be rotated >180°, and the combination can include a shaft, doubling the sensitivity of the seat position data.

[0013] The base assembly can optionally include a plurality of sensors fully enclosed within the base assembly, the plurality of sensors including co-located sensors that sense substantially similar characteristics of the mobility assistance device. The base assembly can optionally include a manual brake including internal components, the internal components including a hard stop and a damper, the manual brake including a brake release lever that is replaceable separately from the internal components.

[0014] The underlying processor can optionally include user-configurable drive options that limit the speed and acceleration of the mobility assist device based on preselected conditions. The motorized balance mobility assist device can optionally include a user control device including a thumbwheel that modifies at least one speed range for the mobility assist device.

[0015] The motorized balance movement assist device can optionally include a drive locking element that enables operable coupling between the base assembly and the docking station, and a skid plate having a pop-out cavity that accommodates the drive locking element and that allows for the accumulation of oil that escapes from the base assembly.

[0016] The motorized balance mobility assistance device may optionally include a seat, wherein the base processor receives an indication that the mobility assistance device is encountering a slope between the ground and the vehicle, the base processor instructs a cluster of wheels to maintain contact with the ground, the base processor changes the orientation of at least one cluster assembly based on the position of the plurality of wheels in accordance with the indication to maintain a center of gravity of the mobility assistance device, and the base processor dynamically adjusts the distance between the seat and the at least one cluster assembly while maintaining the seat as close as possible to the ground to prevent contact between the seat and the plurality of wheels.

[0017] The infrastructure processor may optionally include an obstacle system that includes receiving obstacle data, automatically identifying at least one obstacle in the obstacle data, automatically determining at least one situation identifier, automatically maintaining a distance between the mobility assistance device and the at least one obstacle based on the at least one situation identifier, automatically accessing at least one authorization command associated with the distance, the at least one obstacle, and the at least one situation identifier, automatically accessing at least one automatic response to the at least one movement command, receiving the at least one movement command, automatically mapping one of the at least one movement command and the at least one authorization command, and automatically moving the mobility assistance device based on the at least one movement command and the at least one automatic response associated with the mapped authorization command.

[0018] The infrastructure processor may optionally include a stair processor including the steps of receiving at least one stair command, receiving sensor data from sensors mounted on the mobility assistance device, automatically locating at least one stair structure in the sensor data based on the sensor data, receiving a selection of a selected stair structure of the at least one stair structure, automatically measuring at least one characteristic of the selected stair structure, automatically locating an obstacle on the selected stair structure, if applicable, based on the sensor data, automatically locating a last stair of the selected stair structure based on the sensor data, and automatically navigating the mobility assistance device on the selected stair structure based on the measured at least one characteristic, the last stair, and the obstacle, if applicable.

[0019] The infrastructure processor may optionally include a restroom processor that includes the steps of automatically locating a restroom stall door, automatically moving a mobility assist device through the restroom stall door and into the restroom stall, automatically positioning the mobility assist device relative to restroom fixtures, automatically locating the restroom stall door, and automatically moving the mobility assist device through the restroom stall door and out of the restroom stall.

[0020] The infrastructure processor can optionally include a door processor that includes the steps of receiving sensor data from a sensor mounted on the mobility assist device; automatically identifying a door in the sensor data; automatically measuring the door; automatically determining a door swing; automatically moving the mobility assist device forward through a doorway, where the mobility assist device opens the door and maintains the door in an open position if the door swing is away from the mobility assist device; and automatically positioning the mobility assist device for access to a door handle, where the mobility assist device moves away from the door a distance based on a door width as the door opens, and the mobility assist device moves forward through the doorway, where the mobility assist device maintains the door in an open position if the door swing is toward the mobility assist device.

[0021] The infrastructure processor optionally includes a door processor that includes steps of receiving sensor data from a sensor mounted on the mobility assistance device, automatically identifying a door in the sensor data, automatically measuring the door, including a width of the door, automatically generating an alert if the door is smaller than a preselected size related to a size of the mobility assistance device, automatically positioning the mobility assistance device for access to the door, the positioning based on the width of the door, automatically generating a signal to open the door, and automatically moving the mobility assistance device through the doorway.

[0022] The infrastructure processor may optionally include a docking processor that includes the steps of automatically locating a drop-off point at which the patient dismounts the mobility assist device; automatically positioning the mobility assist device proximate the drop-off point; automatically determining when the patient dismounts the mobility assist device; automatically locating a docking station; automatically positioning the mobility assist device at the docking station; and operably connecting the mobility assist device to the docking station.

[0023] A method of the present teachings for controlling a speed of a mobility assistance device, where the mobility assistance device may include a plurality of wheels and a plurality of sensors, may include, but is not limited to, receiving terrain and obstacle detection data from the plurality of sensors; mapping the terrain and, if applicable, obstacles in real time based on at least the terrain and obstacle detection data; calculating a potential collision area, if applicable, based on at least the mapped data; calculating a deceleration area, if applicable, based on at least the mapped data and the speed of the mobility assistance device; receiving a user preference for a deceleration area and a desired direction and speed of movement, if applicable; calculating wheel commands to command the plurality of wheels based on at least the potential collision area, the deceleration area, and the user preference; and providing the wheel commands to the plurality of wheels.

[0024] A method of the present teachings for moving a balanced mobility assistance device over relatively steep terrain, the mobility assistance device including a wheel cluster and a seat, the wheel cluster and the seat separated by a distance, the distance varying based on preselected characteristics, the method including, but not limited to, receiving an indication that the mobility assistance device will encounter steep terrain, instructing the wheel cluster to maintain contact with the ground, and dynamically adjusting the distance between the seat and the wheel cluster based on maintaining balance of the mobility assistance device and the indication.

[0025] A mobility assist device of the present teachings includes a reliable, lightweight, and stable mobility assist device including a base operably coupled to a user controller. The base can include a base controller, a power controller, a wheel cluster assembly, all-terrain wheels, caster arms, and casters. The base can include, for example, a long-life redundant battery with an on-board battery management system, ergonomically positioned and shock-damped caster wheel assemblies, docking capabilities, universal seat attachment hardware, and an entry / exit management bumper. The base and user controller can communicate with external devices that can, for example, monitor and control the mobility assist device. The mobility assist device can be protected from foreign object ingress and tip-over hazards and can accommodate increased payloads over the prior art.

[0026] The base controller may include, but is not limited to, at least two redundant processors that control the mobility assistance device. At least one user controller may receive desired actions for the mobility assistance device and, together with the base controller, process the desired actions. Each of the at least two processors may include at least one controller processing task. The at least one controller processing task may receive sensor data and motor data associated with sensors and motors that may be operatively coupled to the mobility assistance device. The mobility assistance device may include at least one inertial measurement unit (IMU) board that may be operatively coupled to the base controller. The at least one IMU may be mounted on a daughter board and may be calibrated remotely from the mobility assistance device. The coupling of the daughter board and the base controller may enable shock resistance in the IMU.

[0027] In addition to redundant processors, mobility assistance devices of the present teachings can include reliability features such as redundant motors and sensors, e.g., IMU sensors. Eliminating incorrect data from redundant components can improve the safety and reliability of mobility assistance devices. A method of the present teachings, referred to herein as “voting,” for resolving a value to use from the redundancy of at least one processor of the present teachings can include, but is not limited to, initializing a counter; averaging values ​​from each processor, such as, but not limited to, sensor or command values ​​(referred to herein as processor values); calculating the absolute difference between each processor value and the average value; and discarding the highest difference. The method can further include calculating the differences between the remaining processor values ​​and each other. If any differences greater than a preselected threshold exist, the method can include comparing the remaining values ​​with the value having the highest difference therebetween; voting out the value with the highest difference from the remaining values; comparing the voted-out value with the remaining values; voting out any differences greater than a preselected threshold; and selecting one of the remaining processor values ​​or the average of the processor values. If there is no difference above a preselected threshold, the method may compare the voted-out value with the remaining values. If there are any differences above a preselected threshold, the method may include voting out the value voted-out in the comparing step and selecting one of the remaining processor values ​​or an average of the remaining processor values. If there is no difference above a preselected threshold, the method may include selecting one of the remaining processor values ​​or an average of the remaining processor values. If the processor value is voted out a preselected number of times, the method may include generating an alarm. If the voting scheme fails to find a processor value that meets the selection criteria, the method may include incrementing a counter.If the counter does not exceed a preselected number, the method can include discarding frames with no remaining processor values ​​and selecting a previous frame with at least one processor value that meets the selection criteria. If the frame counter exceeds a preselected number, the method can include transitioning the mobility assist device into a fail-safe mode. A mobility assist device of the present teachings can include a filter for fusing gyroscope and accelerometer data to determine an accurate estimate of a gravity vector, which can be used to define the orientation and inertial rotational rate of the mobility assist device. The orientation and inertial rotational rate of the mobility assist device can be shared and combined across the redundant processors of the present teachings.

[0028] To facilitate a beneficial user experience, the mobility assist device can operate in several functional modes, including, but not limited to, standard, four-wheel, stair, balance, remote, utility, calibration, and optionally docked modes, all described herein. When initially powered on, the mobility assist device can include a predetermined startup process. The mobility assist device can perform self-diagnostics to check the integrity of features of the mobility assist device that are not easily testable during normal operation. When a power-off request is detected by the mobility assist device, it can be subject to a determination of whether the request should be granted. Prior to powering off, the mobility assist device location can be secured, and all status and logged information can be stored.

[0029] In some configurations, mobility assist devices of the present teachings can accommodate a user's varying levels of physical ability and device acumen. In particular, a user can adjust the mobility assist device's response to joystick commands. In some configurations, mobility assist devices of the present teachings can allow user-configurable driving options in the form of joystick command shaping and thumbwheel controls, which can allow individual users to configure mobility assist devices, including user controllers of the present teachings, for their driving preferences. Mobility assist devices of the present teachings can accommodate speed-sensitive steering, which can adjust the mobility assist device's turning behavior as a function of the mobility assist device's speed, making the mobility assist device more responsive at high speeds and less jerky at low speeds.

[0030] In some configurations, a mobility assistance device of the present teachings can still further employ adaptive speed control to assist a user in avoiding potentially hazardous conditions while driving. Adaptive speed control can reduce the required driver concentration by using sensors to detect obstacles and can help a user navigate difficult terrain or situations. A method of the present teachings for adaptive speed control of a mobility assistance device can include, without limitation, receiving terrain and obstacle detection data and mapping the terrain and, if applicable, obstacles in real time based on at least the terrain and obstacle detection data. The method can optionally, if applicable, calculate a virtual groove based on at least the mapped data. The method can still further include calculating, if applicable, a potential collision area based on at least the mapped data, and calculating a deceleration area based on at least the mapped data and the speed of the mobility assistance device. The method can also, if applicable, receive user preferences for the deceleration area and a desired direction and speed of movement. The method may still further include the steps of calculating at least one wheel command based on at least the collision potential area, the deceleration area, and user preferences, and optionally the virtual groove, and providing the at least one wheel command to a wheel motor drive unit.

[0031] A method for obstacle processing of the present teachings may include, without limitation, receiving PCL data, identifying at least one plane in the segmented PCL data, and identifying at least one obstacle in the at least one plane. The method for obstacle processing may further include determining at least one situation identifier based on at least the obstacle, user information, and movement command, and determining a distance between the mobility assistance device and the obstacle based on at least the situation identifier. The method for obstacle processing may also include accessing at least one authorization command associated with the distance, the obstacle, and the situation identifier. The method for obstacle processing may still further include accessing an automatic response to the authorization command, receiving the movement command, mapping one of the movement command and the authorization command, and providing the automatic response associated with the movement command and the mapped authorization command to a mode-dependent processor.

[0032] The obstacle can be stationary or moving. The distance can include a fixed amount and / or can be a dynamically varying amount. The movement commands can include a follow command, a pass-through command, a go-by command, and a not-follow command. The obstacle data can be stored and retrieved, for example, locally and / or in a cloud-based storage area. A method for obstacle processing can include collecting sensor data from a time-of-flight camera mounted on a mobility assistance device, analyzing the sensor data using a point cloud library (PCL), tracking moving objects using SLAM based on the location of the mobility assistance device, identifying planes in the obstacle data, and providing an automatic response associated with the mapped clearance command to a mode-dependent processor. The method for obstacle processing can receive a resume command and, following the resume command, provide an automatic response associated with the movement command and the mapped clearance command to a mode-dependent processor. The automatic response can include a speed control command.

[0033] The obstacle processor of the present teachings may include, but is not limited to, a navigation / PCL data processor. The navigation / PCL processor may receive and segment PCL data from the PCL processor, identify a plane within the segmented PCL data, and identify an obstacle within the plane. The obstacle processor may include a distance processor. The distance processor may determine a situation identifier based on the user information, the movement command, and the obstacle. The distance processor may determine a distance between the mobility assistance device and the obstacle based on at least the situation identifier. The moving object processor and / or the stationary object processor may access an authorization command associated with the distance, the obstacle, and the situation identifier. The moving object processor and / or the stationary object processor may access an automatic response from an automatic response list associated with the authorization command. The moving object processor and / or the stationary object processor may access the movement command and map the movement command to one of the authorization commands. The moving object processor and / or the stationary object processor may provide the automatic response associated with the movement command and the mapped authorization command to the mode-dependent processor. Movement commands can include a follow command, a pass command, a by command, a move to a fixed position command, and a no-follow command. The Nav / PCL processor can store obstacles in local storage and / or on a storage cloud and can enable access to the stored obstacles by systems external to the mobility assistance device.

[0034] In some configurations, mobility assistance devices of the present teachings can include a weight-sensitive controller that can adapt to various user needs. Additionally, the weight-sensitive controller can detect sudden changes in weight, such as, but not limited to, when a user dismounts from the mobility assistance device. The user's weight and center of gravity location can be significant contributors to system dynamics. By sensing the user's weight and adjusting the controller, improved active response and stability of the mobility assistance device can be achieved.

[0035] A method of the present teachings for stabilizing a mobility assist device may include, but is not limited to, estimating a weight and / or change in weight of a load on the mobility assist device, selecting a default value or values ​​for the center of gravity of the mobility assist device and load combination, calculating a controller gain based on at least the weight and / or change in weight and the center of gravity value, and applying the controller gain to control the mobility assist device. A method of the present teachings for calculating a weight of a load on a mobility assist device may include, but is not limited to, receiving a position of the load on the mobility assist device, receiving a setting of the mobility assist device to a standard mode, measuring at least once a motor current required to transition the mobility assist device to an enhanced mode, calculating a torque based at least on the motor current, calculating a weight of the load based at least on the torque, and adjusting a controller gain based at least on the calculated weight to stabilize the mobility assist device.

[0036] In some configurations, a mobility assistance device of the present teachings can include traction control, which adjusts the torque applied to the wheels and can affect directional and acceleration control. In some configurations, traction control can be assisted by rotating the cluster so that all four wheels contact the ground when braking above a certain threshold is required. A method of the present teachings for controlling traction of a mobility assistance device can include, but is not limited to, calculating the linear acceleration of the mobility assistance device and receiving an IMU-measured acceleration of the mobility assistance device. If the difference between the expected linear acceleration and the measured linear acceleration of the mobility assistance device exceeds or equals a preselected threshold, adjusting the torque to the cluster / wheel motor drive. If the difference between the expected linear acceleration and the measured linear acceleration of the mobility assistance device is less than a preselected threshold, the method can continue testing for loss of traction.

[0037] A mobility assist device of the present teachings can include a user controller (UC) assist that can assist a user in avoiding obstacles, passing through doors, climbing stairs, entering elevators, and parking / transporting the mobility assist device. The UC assist can receive user input and / or input from components of the mobility assist device and can enable the invocation of an automatically or manually selected processing mode. A command processor can enable the invoked mode by generating movement commands based at least on previous movement commands, data from the user, and data from sensors. The command processor can receive user data, which can include signals from a joystick, which can provide an indication of the desired direction and speed of movement of the mobility assist device. The user data can also include a mode selection to which the mobility assist device can be transitioned. Modes such as door mode, restroom mode, extended stair mode, elevator mode, dynamic storage mode, and static storage / charging mode can be selected. Any of these modes can include a move-to-place mode, or the user can instruct the mobility assist device to move to a location. The UC assist can generate commands such as movement commands, which may include, but are not limited to, speed and direction, and the movement commands can be provided to the wheel motor drive and the cluster motor drive.

[0038] Sensor data is collected by a sensor handling processor, which may include, but is not limited to, a geometry processor, a point cloud library (PCL) processor, a simultaneous localization and mapping (SLAM) processor, and an obstacle processor. Movement commands can also be provided to the sensor handling processor. The sensors can provide environmental information, which may include, for example, but is not limited to, geometric information about obstacles and the mobility assistance device. The sensors can include at least one time-of-flight sensor, which may be mounted anywhere on the mobility assistance device. Multiple sensors can be mounted on the mobility assistance device. The PCL processor can collect and process the environmental information and produce PCL data, which can be processed by the PCL library.

[0039] The geometry processor of the present teachings can receive geometry information from the sensors, perform any processing necessary to prepare the geometry information for use by the mode-dependent processor, and provide the processed geometry information to the mode-dependent processor. The geometry of the mobility assistance device can be used to automatically determine whether the mobility assistance device can fit into and / or through a space, such as, for example, a staircase structure and a door. The SLAM processor can determine navigation information based on, for example, but not limited to, user information, environmental information, and movement commands. The mobility assistance device can navigate within a path set, at least in part, by the navigation information. The obstacle processor can locate obstacles and distances to the obstacles. Obstacles can include, but are not limited to, doors, stairs, cars, and miscellaneous features near the path of the mobility assistance device.

[0040] A method of the present teachings for navigating stairs may include, but is not limited to, receiving a stair command and receiving environmental information from an obstacle processor. The method for navigating stairs may include, based on the environmental information, locating a stair structure within the environmental information and receiving a selection of one of the stair structures located by the obstacle processor. The method for navigating stairs may also include measuring characteristics of the selected stair structure and locating, if applicable, an obstacle on the selected stair structure based on the environmental information. The method for navigating stairs may also include locating, based on the environmental information, the last step of the selected stair structure, and, based on the measured characteristics, the last step, and, if applicable, the obstacle, providing movement commands and moving the mobility assistance device on the selected stair structure. The method for navigating stairs may continue providing movement commands until the last step is reached. The characteristics may include, but are not limited to, the height of the stair risers of the selected stair structure, the surface texture of the risers, and the surface temperature of the risers. If the surface temperature is outside a threshold range and the surface texture is outside a static friction setting, an alert may be generated.

[0041] The stair navigation processor of the present teachings may include, but is not limited to, a stair structure processor that receives at least one stair command included in the user information and a stair structure locator that receives environmental information from sensors mounted on the mobility assistance device, for example, through an obstacle processor. The stair structure locator can locate a stair structure within the environmental information based on the environmental information and can receive a selected stair structure option. The stair characteristic processor can measure characteristics of the selected stair structure and locate obstacles, if applicable, on the selected stair structure based on the environmental information. The stair movement processor can locate the last stair of the selected stair structure based on the environmental information and can provide movement commands to the movement processor to instruct the mobility assistance device to move on the selected stair structure based on the characteristics, the last stair, and the obstacles, if applicable. The stair structure locator can locate the stair structure based on GPS data and can build and store a map of the selected stair structure. The map can be stored locally and / or for use by other devices unrelated to the mobility assistance device. The stair structure processor can access the geometry of the mobility assist device, compare the geometry to characteristics of the selected stair structure, and modify navigation of the mobility assist device based on the comparison. The stair structure processor can optionally generate an alert if the surface temperature of the risers of the selected stair structure is outside a threshold range and the surface texture of the selected stair structure is outside a static friction setting. The stair movement processor can determine the topography of an area surrounding the selected stair structure based on the environmental information and can generate an alert if the topography is not flat. The stair movement processor can access a set of extreme conditions that can be used to modify movement commands generated by the stair movement processor.

[0042] When a mobility assist device crosses a door threshold, where the door may include a door swing, a hinge location, and a doorway, a method of the present teachings for navigating a door may include receiving and segmenting environmental information from sensors mounted on the mobility assist device. The environmental information may include the geometry of the mobility assist device. The method may include identifying a plane within the segmented sensor data and identifying a door within the plane. The method for navigating a door may include measuring the door and, if the door measurement is smaller than the mobility assist device, providing a movement command that may move the mobility assist device away from the door. The method for navigating a door may include determining the door swing and providing a movement command to move the mobility assist device to access the door handle. The method for navigating a door may include providing a movement command to move the mobility assist device away from the door a distance based on the door measurement as the door opens. The method for navigating a door may include providing a movement command to move the mobility assist device forward through the doorway. The mobility assist device can maintain the door in an open position when the door swings toward the mobility assist device.

[0043] A method of processing sensor data according to the present teachings can determine the hinge side of a door, the direction and angle of the door, and the distance to the door through information from the sensors. A movement processor according to the present teachings can generate commands to the MD, such as start / stop left turn, start / stop right turn, start / stop forward movement, and start / stop backward movement, and can facilitate door mode by stopping the mobility assist device, canceling a goal the mobility assist device may be completing, and centering the joystick. A door processor according to the present teachings can determine whether the door is, for example, a push door, a sliding door, or a sliding door. The door processor can determine the width of the door and the x / y / z location of the door pivot point based on the current position and orientation of the mobility assist device. If the door processor determines that the number of valid points in the image of the door derived from the set of obstacles and / or PCL data exceeds a threshold, the door processor can determine the distance from the mobility assist device to the door. The door processor can determine whether the door is moving based on successive samples of PCL data from the sensor processor. In some configurations, the door processor can assume that the side of the mobility assist device is parallel to the handle side of the door and can use that assumption to determine the width of the door, along with the location of the door pivot point. The door processor can generate commands to move the mobility assist device through the door based on the door swing and door width. The mobility assist device itself can hold the door open while the mobility assist device traverses the door threshold.

[0044] In some configurations, the mobility assist device can automatically negotiate use of restroom facilities. Restroom and restroom stall doors can be located as discussed herein, and the mobility assist device can be moved to a location relative to the door as discussed herein. Fixtures in the restroom can be located as obstacles as discussed herein, and the mobility assist device can automatically position itself near the fixtures to provide the user with access to, for example, a toilet, sink, and changing table. The mobility assist device can automatically navigate to exit restroom stalls and restrooms through the door and obstacle handling discussed herein. The mobility assist device can automatically traverse door thresholds based on the geometry of the mobility assist device.

[0045] For example, but not limited to, a method of the present teachings for automatically storing a mobility assist device in a vehicle, such as a wheelchair-accessible van, can aid a user's independent use of the vehicle. When the user exits the mobility assist device and enters the vehicle, potentially as the vehicle's driver, the mobility assist device can remain parked outside the vehicle. If the mobility assist device is to be carried by the user in the vehicle for later use, the dynamic parking mode of the present teachings can provide a movement command to the mobility assist device, causing it to store and then retrieve the mobility assist device body, either automatically or in response to a command, at the vehicle door. The mobility assist device can be commanded to store the body, for example, through a command received from an external application. In some configurations, a computer-driven device, such as a cell phone, laptop, and / or tablet, can be used to run one or more external applications and generate information that can ultimately control the mobility assist device. In some configurations, the mobility assist device can automatically proceed to dynamic parking mode after the user exits the mobility assist device. The movement commands can include commands to locate a vehicle door that the mobility assist device will enter to be stored and commands to point the mobility assist device toward the vehicle door. The dynamic parking mode can determine an error condition, such as, for example, but not limited to, if the vehicle door is too small for the mobility assist device to enter, and the dynamic parking mode can alert the user of the error condition, for example, but not limited to, through an audio alert through an audio interface and / or a message to one or more external applications. If the vehicle door is wide enough for the mobility assist device to enter, the dynamic parking mode can provide vehicle control commands to command the vehicle to open the vehicle door. The dynamic parking mode can determine when the vehicle door is open and whether there is space for the mobility assist device to be stored.The dynamic parking mode can invoke methods for obstacle handling to help determine the status of the vehicle doors and whether there is room within the vehicle to store the mobility assist device. If there is enough room for the mobility assist device, the dynamic parking mode can provide a movement command to move the mobility assist device into a storage space within the vehicle. Vehicle control commands can be provided to command the vehicle to lock the mobility assist device in place and close the vehicle doors. When the mobility assist device is needed again, one or more external applications can be used, for example, to return the mobility assist device to the user. The status of the mobility assist device can be recalled, and vehicle control commands can command the vehicle to unlock the mobility assist device and open the vehicle doors. The vehicle doors can be located, and the mobility assist device can be moved through the vehicle doors, for example, to a passenger door commanded by one or more external applications. In some configurations, the vehicle can be tagged at a fixed location, such as a vehicle entrance door, where the mobility assist device can be stored.

[0046] A method of the present teachings for storing / recharging a mobility assist device can assist a user in storing and potentially recharging the mobility assist device, potentially while the user sleeps. After the user dismounts from the mobility assist device, a command can be initiated by one or more external applications to move the mobility assist device, possibly unoccupied, to a storage / docking area. In some configurations, a mode selection by the user while using the mobility assist device can initiate an automatic storage / docking function after the user dismounts from the mobility assist device. When the mobility assist device is needed again, a command can be initiated by one or more external applications to direct the mobility assist device to the user. A method for storing / recharging a mobility assist device can include, but is not limited to, locating at least one storage / charging area, providing at least one movement command, and moving the mobility assist device from a first location to the storage / charging area. A method for storing / recharging a mobility assist device can include locating a charging dock within the storage / charging area, providing at least one movement command, and coupling the mobility assist device to the charging dock. The method for storing / recharging a mobility assistance device can optionally include, upon the mobility assistance device receiving the wake-up command, providing at least one movement command and moving the mobility assistance device to a first location. If a storage / charging area does not exist, or if a charging dock does not exist, or if the mobility assistance device cannot be coupled to a charging dock, the method for storing / recharging a mobility assistance device can optionally include providing at least one alert to a user, and providing at least one movement command and moving the mobility assistance device to the first location.

[0047] The method of the present teachings for negotiating with an elevator while maneuvering a mobility assist device can allow a user to ascend and descend an elevator while remaining seated in the mobility assist device. When the elevator is automatically located, for example, and the user selects a desired elevator direction, and when the elevator arrives and the doors open, movement commands can be provided to move the mobility assist device into the elevator. The elevator geometry can be determined, and movement commands can be provided to move the mobility assist device to a location that allows the user to select a desired activity from an elevator selection panel. The location of the mobility assist device can also be appropriate for exiting the elevator. Once the elevator doors open, movement commands can be provided to move the mobility assist device and exit the elevator entirely.

[0048] A motorized balance mobility assist device of the present teachings can include a base assembly including, but not limited to, a base controller and a power controller. The power controller can provide power to the base controller, and the base assembly can process movement commands for the mobility assist device. The motorized balance mobility assist device can include a cluster assembly operably coupled to the base assembly. The cluster assembly can include an operably coupled to a plurality of wheels. The wheels can support the base assembly and can move based on the processed movement commands. The base assembly and cluster assembly can enable balancing of the mobility assist device on two of the plurality of wheels.

[0049] The motorized balance transfer assist device may optionally include caster arms that may be operably coupled to the base assembly. The caster arms may include operably coupled to caster wheels, which may support the base assembly. The motorized balance transfer assist device may optionally include a seat support assembly that may enable connection of the seat to the base assembly. The base assembly may include a seat position sensor, which may provide seat position data to the base assembly. The motorized balance transfer assist device may optionally include terrain wheels, which may include means for user attachment / detachment capability. The motorized balance transfer assist device may optionally include a base controller board that includes a base controller and at least one inertial measurement unit (IMU). The at least one IMU may be mounted on the IMU board, and the IMU may be flexibly coupled to the base controller board. The IMU board may be separate from the base controller board, and the at least one IMU may be calibrated in isolation from the base controller board.

[0050] The motorized balance and movement assist device may optionally include at least one field effect transistor (FET) positioned on a base controller board and at least one heat spreader plate that receives heat from the FET. The at least one heat spreader plate may transfer heat to a chassis of the mobility assist device. The motorized balance and movement assist device may optionally include at least one motor that is thermocompression bonded into at least one housing of the mobility assist device and at least one thermistor associated with the at least one motor, the at least one thermistor enabling reduced power usage when the associated at least one motor exceeds a thermal threshold. The motorized balance and movement assist device may optionally include multiple batteries that may power the mobility assist device. The multiple batteries may be mounted with a mounting gap between each pair of batteries. The batteries may be connected to the base assembly through an environmentally isolated seal. The motorized balance and movement assist device may optionally include a base controller board that may include redundant processors. The redundant processors may be physically separated from each other and may be based on a voting process to allow for fault tolerance.

[0051] The motorized balance transfer assist device may optionally include a drive locking element that may enable operable coupling between the base assembly and the docking station. The motorized balance transfer assist device may optionally include a skid plate having a pop-out cavity that may accommodate the drive locking element. The skid plate may allow for the accumulation of oil that escapes from the base assembly. The motorized balance transfer assist device may optionally include an anti-tip process that may reduce the likelihood of the mobility assist device tipping over. The motorized balance transfer assist device may optionally include a field weakening process that may enable the mobility assist device to manage abnormal situations by providing relatively short bursts of relatively high motor speed. The motorized balance transfer assist device may optionally include a stair climbing failsafe that may force the mobility assist device to tip backward if stability is lost during stair climbing. The motorized balance transfer assist device may optionally include at least one magnet mounted within the cluster assembly. The at least one magnet may attract particles within the cluster assembly. The motorized balance movement assist device can optionally include at least one seal between the sections of the cluster assembly. The motorized balance movement assist device can optionally include an electrical connector, which can include a printed circuit board (PCB) with electromagnetic (EM) energy shielding. The PCB can disable the transmission of EM energy along a cable associated with the electrical connector.

[0052] Mobility assistance devices of the present teachings may include, but are not limited to, seats and clusters. The mobility assistance device may include a fully internal and redundant sensor system, where the sensor system may include multiple sensors. The multiple sensors may include multiple absolute position sensors that may enable new location reports if the seats and / or clusters move while the mobility assistance device is powered off. The multiple sensors may include multiple seat sensors and multiple cluster sensors that operate while the mobility assistance device is powered on. The sensor system may enable failover from a failing one of the multiple sensors to another of the multiple sensors. The multiple sensors may include co-located sensors that may sense substantially similar characteristics of the mobility assistance device. The mobility assistance device may include an environmentally isolated gearbox. The contents of the gearbox may be shielded from physical contaminants and electromagnetic transmissions. The gearbox may be lubricated by an oil port within the housing of the mobility assistance device. The mobility assistance device may include a manual brake, which may include a hard stop and a damper. The manual brake may include a brake release lever isolated from the contents of the gearbox. The manual brake may include a mechanically isolated sensor that reports when the manual brake is engaged, and the isolated sensor may include a magnetic flux shield.

[0053] A method of the present teachings for establishing a center of gravity for a mobility assist device / user pair, wherein the mobility assist device can include a balance mode that can balance the mobility assist device / user pair, and the mobility assist device can include at least one wheel cluster and a seat, can include, but is not limited to, the steps of: (1) entering the balance mode; (2) measuring data including a pitch angle required to maintain balance at a preselected position of the at least one wheel cluster and a preselected position of the seat; (3) moving the mobility assist device / user pair to a plurality of preselected points; (4) repeating step (2) at each of the plurality of preselected points; (5) verifying that the measured data is within preselected limits; and (6) generating a set of calibration coefficients for establishing the center of gravity during operation of the mobility assist device. The calibration coefficients can be based at least on the verified measurement data. The method can optionally include storing the verified measurement data in non-volatile memory.

[0054] A method of the present teachings for filtering parameters associated with movement of a mobility assistance device having an IMU, the IMU including a gyroscope, the gyroscope including a gyroscope bias and gyroscope data, includes, but is not limited to, the steps of: (1) subtracting the gyroscope bias from the gyroscope data to correct the gyroscope data; (2) integrating the filtered gravity velocity over time to obtain a filtered gravity vector; (3) calculating a gravity velocity vector and a predicted gravity velocity estimate based on at least the filtered body velocity and the filtered gravity vector; and (4) subtracting a product of a first gain K1 and a gravity vector error from the gravity velocity vector, wherein the gravity vector error is a function of at least the filtered gravity vector and the measured gravity vector. (5) calculating a pitch velocity, a roll velocity, a yaw velocity, a pitch, and a roll of the mobility assist device based on the filtered gravity velocity vector and the filtered body velocity; (6) subtracting a differential wheel velocity between the wheels of the mobility assist device from the predicted gravity velocity estimate to determine a predicted velocity error and a gyroscope bias; (7) calculating a cross product of the gravity vector error and the filtered gravity vector and adding the cross product to a dot product of the filtered gravity vector and the predicted gravity velocity estimate error to determine a body velocity error; (8) applying a second gain to the integral of the body velocity error over time to determine a gyroscope bias; and (9) looping through steps (1)-(8) to continuously correct the gyroscope data.

[0055] A method of the present teachings for making an all-terrain wheel pair can include, but is not limited to, constructing an inner wheel having at least one locking pin receiver, the inner wheel having a retaining lip that accommodates a twist-lock attachment, and constructing an outer wheel having an attachment base. The attachment base can include a locking pin cavity, which can accommodate a locking pin. The locking pin cavity can include at least one retaining tang that can accommodate the twist-lock attachment. The method can include attaching the outer wheel to the inner wheel by engaging the locking pin with one of the at least one locking pin receiver and the retaining lip with the at least one retaining tang.

[0056] A method of the present teachings for navigating over rough terrain in a mobility assist device can include, but is not limited to, attaching an inner ring having at least one locking pin receiver. The inner ring can include a retaining lip that accommodates a twist-lock attachment. The method can include attaching an outer ring having at least one retention tang and an attachment base having a locking pin cavity to the inner ring by threading the locking pin into the locking pin cavity, engaging the locking pin with one of the at least one locking pin receivers, and engaging the retaining lip with the at least one retention tang.

[0057] An all-terrain wheel pair of the present teachings can include, but is not limited to, an inner wheel having at least one locking pin receiver. The inner wheel can include a retaining lip that accommodates a twist lock attachment. The wheel pair can include an outer wheel having an attachment base. The attachment base can include a locking pin cavity that can accommodate a locking pin. The locking pin cavity can include at least one retaining tang that can accommodate the twist lock attachment. The outer wheel can be attached to the inner wheel by engaging the locking pin with one of the at least one locking pin receiver and the retaining lip with the at least one retaining tang.

[0058] A user controller for a mobility assistance device of the present teachings may include, but is not limited to, a thumbwheel that can modify at least one speed range for the mobility assistance device. The thumbwheel can generate a signal during movement of the thumbwheel, and the signal can be provided to the user controller. The user controller can maintain environmental isolation from the thumbwheel while receiving the signal. The user controller can optionally include a first casing component including at least one speaker, at least one circuit board, and mounting features for at least one control device. The control device can enable selection of at least one option for the mobility assistance device. The user controller can optionally include at least one first environmental isolation device and a second casing component that can include mounting features for at least one display, at least one selection device, and at least one antenna. The second casing component and the first casing component can be operably coupled to the periphery of the at least one first environmental isolation device. The at least one display enables monitoring of the status of the mobility assistance device, and the at least one display can present at least one option. The at least one selection device can enable selection of at least one option. The user controller can optionally include a power / data cable that enables power to flow from the mobility assistance device to the user controller. The power / data cable can enable data exchange between the user controller and the mobility assistance device. The user controller can optionally include a first component for a toggle platform that includes a toggle. The toggle can enable selection of the at least one option. The user controller can optionally include at least one second environmental isolation device and a second component for a toggle platform that can include a mobility assistance device mounting feature.The toggle platform second component and the toggle platform first component can be operably coupled to a periphery of the at least one second environmental isolation device. The mobility assistance device mounting feature can enable mounting of a user controller on the mobility assistance device. The user controller can optionally include a two-way shortcut toggle, a four-way shortcut toggle, and at least one integrating device that integrates the two-way shortcut toggle and the four-way shortcut toggle.

[0059] The at least one option can include a desired speed, a desired direction, a speed mode, a mobility assistance device mode, a seat height, a seat tilt, and a maximum speed. The control device can include at least one joystick and at least one thumbwheel. The at least one joystick can enable receiving a desired speed and a desired direction, and the at least one thumbwheel can enable receiving a maximum speed. The at least one toggle can include at least one toggle switch and at least one toggle lever. The at least one display can include at least one battery status indicator, a power switch, at least one audible alert and mute capability, and at least one antenna for receiving wireless signals.

[0060] A thumbwheel for a user controller of the present teachings may include, but is not limited to, a one-turn selector that enables movement of the thumbwheel and can produce movement data throughout one full revolution of the thumbwheel. The movement data can be dynamically associated with at least one user controller characteristic. The thumbwheel may include a thumbwheel position, at least one sensor that receives the movement data, and a memory that can retain the thumbwheel position and the at least one user controller characteristic across a power-down state. The at least one user controller characteristic may include a maximum speed. The at least one sensor may be environmentally isolated from the user controller. The at least one sensor may include a Hall Effect sensor.

[0061] A method of the present teachings for controlling the speed of a mobility assistance device including a non-stop thumbwheel and a joystick, where the thumbwheel includes a persistently stored position, can include, but is not limited to, the steps of: (a) accessing a relationship between changes in the rotational position of the thumbwheel and a multiplier for the maximum speed of the personal transport device; (b) receiving changes in the persistently stored position of the non-stop thumbwheel; (c) determining a multiplier based on the changes and the relationship; (d) persistently storing the changed position; (e) receiving a speed signal from the joystick; (f) adjusting the speed signal based on the multiplier; and (g) repeating steps (a) through (f) while the mobility assistance device is active. The method can optionally include receiving an indication of the sensitivity of the thumbwheel and adjusting the relationship based on the indication. The multiplier can be <1.

[0062] Mobility assist devices of the present teachings can overcome limitations of the prior art by including redundancy, lightweight housings, inertial measurement systems, advanced thermal management strategies, wheels and cluster gear trains specifically designed with wheelchair users in mind, lightweight and long-life redundant batteries, ergonomically positioned and shock-damped caster wheel assemblies, and ingress / egress management bumpers. Other improvements can include, but are not limited to, automatic mode transitions, tip-over prevention, improved performance, remote control, universal mounting for the vehicle locking mechanism and the locking mechanism itself, foreign object seals, tilt management, and cabled charging ports. Due to the reduced weight of the mobility assist device, the mobility assist device can accommodate increased payloads over the prior art. The present specification also provides, for example, the following items: (Item 1) 1. A powered balance assistance device, comprising: a base assembly that processes movement commands for the mobility assist device; at least one cluster assembly operably coupled to the base assembly, the at least one cluster assembly operably coupled to a plurality of wheels, the plurality of wheels supporting the base assembly, the plurality of wheels and the at least one cluster assembly moving the mobility assistance device based at least on the processed movement commands; an active stabilization processor that estimates a center of gravity of the mobility assist device, the active stabilization processor estimating at least one value associated with the mobility assist device that is required to maintain balance of the mobility assist device based on the estimated center of gravity; wherein the infrastructure processor actively balances the mobility assist device on at least two of the plurality of wheels based on at least the at least one value. (Item 2) The base assembly includes: redundant motors for moving the at least one cluster assembly and the plurality of wheels; a redundant sensor that senses sensor data from the redundant motor and the at least one cluster assembly; a redundant processor executing within the substrate assembly, the redundant processor selecting information from the sensor data, the selection based on a match of sensor data between the redundant processors, and the redundant processor processing the movement command based at least on the selected information; Item 2. The motorized balance transfer assist device according to item 1, comprising: (Item 3) 1. A tip-over prevention controller that stabilizes the mobility assistance device based on a stabilization factor, the tip-over prevention controller executing commands including calculating a stabilization metric, calculating a stabilization factor, determining movement command information required to process the movement command, and if the stabilization metric indicates that stabilization is required, processing the movement command based on the movement command information and the stabilization factor. Item 1, further comprising: (Item 4) Item 1 . The powered balance mobility assist device of item 1, further comprising a stair-climbing failsafe means for forcing the mobility assist device to safely tip over if stability is lost during stair climbing. (Item 5) a caster wheel assembly operably coupled to the base assembly; a linear acceleration processor that calculates a mobility assistance device acceleration of the mobility assistance device based at least on the wheel speeds, the linear acceleration processor calculating an inertial sensor acceleration of an inertial sensor mounted on the mobility assistance device based at least on sensor data from the inertial sensor; a traction control processor that calculates a difference between the mobility assistance device acceleration and the inertial sensor acceleration, the traction control processor comparing the difference to a preselected threshold; a wheel / cluster command processor that commands the at least one cluster assembly to lower at least one of the plurality of wheels and the caster assembly to the ground based on at least the comparison; Item 1, further comprising: (Item 6) Item 10. The motorized balance movement assistance device of item 1, wherein the base processor uses field weakening to provide bursts of speed to motors associated with the at least one cluster assembly and the plurality of wheels. (Item 7) 2. The powered balance mobility assist device of claim 1, wherein the infrastructure processor estimates the center of gravity of the mobility assist device, the infrastructure processor performing the steps of: (1) measuring data including a pitch angle required to maintain balance of the mobility assist device at a preselected position of the at least one wheel cluster and a preselected position of a seat; (2) moving the mobility assist device / user pair to a plurality of points and repeating step (1) at each of the plurality of points; (3) verifying that the measured data is within preselected limits; and (4) generating a set of calibration coefficients to establish the center of gravity during operation of the mobility assist device, the calibration coefficients being based at least on the verified measurement data. (Item 8) 8. The balance mobility assist device of claim 7, wherein the underlying processor includes a closed-loop controller that maintains stability of the mobility assist device, the closed-loop controller automatically slowing forward motion and accelerating backward motion under preselected conditions, the preselected conditions being based on a pitch angle of the mobility assist device and a center of gravity of the mobility assist device. (Item 9) Item 1. The powered balance mobility assist device of item 1, comprising an all-terrain wheel pair including an inner wheel having at least one locking means accessible by an operator of the mobility assist device while the mobility assist device is in operation, the inner wheel having at least one retaining means, the all-terrain wheel pair including an outer wheel having an attachment base, the attachment base housing the at least one locking means and the at least one retaining means, the at least one retaining means operable by the operator to connect the inner wheel to the outer wheel while the mobility assist device is in operation. (Item 10) Item 10. The motorized balance movement assistance device of item 1, comprising a base processor board including at least one inertial sensor, the at least one inertial sensor being mounted on the inertial sensor board, the at least one inertial sensor board being flexibly coupled to the base processor board, the at least one inertial sensor board being separate from the base processor board, and the at least one inertial sensor being calibrated in isolation from the base processor board. (Item 11) Item 1 , a motorized balance transfer assist device according to item 1, comprising at least one inertial sensor including a gyroscope and an accelerometer. (Item 12) The base processor includes: a mobility assistance device wireless processor that enables communication with external applications electronically remote from the mobility assistance device, the mobility assistance device wireless processor receiving and decoding incoming messages over wireless radio waves, and the infrastructure processor controlling the mobility assistance device based on at least one of the decoded incoming messages; Item 1. The powered balance transfer assist device according to item 1. (Item 13) The base processor includes: a secure wireless communication system including data obfuscation and challenge / response authentication; Item 1. The powered balance transfer assist device according to item 1. (Item 14) Item 10. The motorized balance mobility assist device of item 1, further comprising an indirect heat dissipation path between the base processor board and a chassis of the mobility assist device. (Item 15) Item 10. The powered balance transfer assist device of item 1, further comprising a seat support assembly that allows connection of multiple seat types to the base assembly, the base assembly having a seat position sensor that provides seat position data to the base processor. (Item 16) The seat support assembly includes: a seat lift arm for lifting the seat; a shaft operatively coupled to the seat lift arm, the shaft rotation being measured by the seat position sensor, the shaft rotating <90°, the shaft coupled to the seat position sensor by a single stage gear train rotating the seat position sensor >180°, the combination doubling the sensitivity of the seat position data; Item 12. The motorized balance transfer assist device according to Item 11, comprising: (Item 17) The base assembly includes: a plurality of sensors fully enclosed within the base assembly, the plurality of sensors including co-located sensors that sense substantially similar characteristics of the mobility assistance device; Item 12. The motorized balance transfer assist device according to item 11. (Item 18) The base assembly includes: a manual brake including internal components, the internal components including a hard stop and a damper, the manual brake including a brake release lever that is replaceable separately from the internal components; Item 1. The powered balance transfer assist device according to item 1. (Item 19) The base processor includes: user-configurable drive options that limit the speed and acceleration of the mobility assistance device based on preselected conditions; Item 1. The powered balance transfer assist device according to item 1. (Item 20) Item 10. The motorized balance mobility assist device of item 1, further comprising a user control device including a thumbwheel, the thumbwheel modifying at least one speed range for the mobility assist device. (Item 21) a drive locking element that allows operable coupling between the base assembly and a docking station; a skid plate having a pop-out cavity that accommodates the drive locking element, the skid plate allowing for the accumulation of oil that escapes from the base assembly; Item 1, further comprising: (Item 22) More seating available. the infrastructure processor receives an indication that the mobility assistance device is encountering a slope between the ground and the vehicle, the infrastructure processor instructs the wheel cluster to maintain contact with the ground, the infrastructure processor changes an orientation of the at least one cluster assembly based on a position of the plurality of wheels in accordance with the indication to maintain a center of gravity of the mobility assistance device, and the infrastructure processor dynamically adjusts a distance between the seat and the at least one cluster assembly while maintaining the seat as close as possible to the ground to prevent contact between the seat and the plurality of wheels. Item 1. The powered balance transfer assist device according to item 1. (Item 23) The base processor includes: receiving obstacle data; automatically identifying at least one obstacle in the obstacle data; automatically determining at least one context identifier; automatically maintaining a distance between the mobility assistance device and the at least one obstacle based on the at least one situation identifier; automatically accessing at least one authorization command associated with the distance, the at least one obstacle, and the at least one situation identifier; automatically accessing at least one automatic response to at least one movement command; receiving at least one movement command; automatically mapping one of the at least one movement command and the at least one authorization command; automatically moving the mobility assistance device based on at least one automatic response associated with the at least one movement command and the mapped authorization command; and an obstacle system including: Item 1. The powered balance transfer assist device according to item 1. (Item 24) The base processor includes: receiving at least one stair command; receiving sensor data from sensors mounted on the mobility assistance device; automatically locating at least one staircase structure within the sensor data based on the sensor data; receiving a selection of a selected stair structure of the at least one stair structure; automatically measuring at least one characteristic of the selected staircase structure; automatically locating obstacles on the selected stair structure, if applicable, based on the sensor data; and automatically locating a last stair of the selected stair structure based on the sensor data; automatically navigating the mobility assistance device on the selected stair structure based on the at least one measured characteristic, the last stair, and, if applicable, the obstacle; and a staircase processor including: Item 1. The powered balance transfer assist device according to item 1. (Item 25) The base processor includes: automatically locating a restroom stall door; automatically moving the mobility assistance device through a restroom stall door and into the restroom stall; automatically positioning the mobility assistance device relative to restroom fixtures; automatically locating a door of the restroom stall; automatically moving the mobility assistance device through a door of the restroom stall and exiting the restroom stall. a restroom processor, including Item 1. The powered balance transfer assist device according to item 1. (Item 26) The base processor includes: receiving sensor data from sensors mounted on the mobility assistance device; automatically identifying a door in the sensor data; automatically measuring the door; Automatically determining door swing; automatically moving the mobility assist device forward through a doorway, the mobility assist device opening the door and maintaining the door in an open position when the door swing is away from the mobility assist device; automatically positioning the mobility assist device for access to the door handle, moving the mobility assist device away from the door as the door opens a distance based on the width of the door, and moving the mobility assist device forward through the doorway, wherein the mobility assist device maintains the door in an open position when the door swings toward the mobility assist device; a door processor, Item 1. The powered balance transfer assist device according to item 1. (Item 27) The base processor includes: receiving sensor data from sensors mounted on the mobility assistance device; automatically identifying a door in the sensor data; automatically measuring the door, including the width of the door; automatically generating an alert if the door is smaller than a preselected size related to a size of the mobility assistance device; automatically positioning the mobility assist device for access to the door, the positioning based on a width of the door; and automatically generating a signal to open the door; automatically moving the mobility assistance device through the doorway; Item 10. The powered balance transfer assist device of item 1, comprising a door processor including: (Item 28) The base processor includes: automatically locating a drop-off point where the patient dismounts from the mobility assistance device; automatically positioning the mobility assistance device proximate the drop-off point; automatically determining when the patient dismounts from the mobility assistance device; automatically locating a docking station; automatically positioning the mobility assistance device in the docking station; operably connecting the mobility assist device to the docking station; a docking processor including: Item 1. The powered balance transfer assist device according to item 1. (Item 29) 1. A method for controlling a speed of a mobility assistance device, the mobility assistance device including a plurality of wheels, the mobility assistance device including a plurality of sensors, the method comprising: receiving terrain and obstacle detection data from the plurality of sensors; mapping terrain and, if applicable, obstacles in real time based on at least said terrain and obstacle detection data; calculating a collision potential area, if applicable, based on at least said mapped data; calculating a deceleration area, if applicable, based on at least the mapped data and the speed of the mobility assistance device; receiving user preferences regarding said deceleration area and desired direction and speed of motion, if applicable; calculating wheel commands for commanding the plurality of wheels based on at least the potential collision area, the deceleration area, and the user preferences; providing the wheel commands to the plurality of wheels; A method comprising: (Item 30) 1. A method for moving a balance mobility assist device over relatively steep terrain, the mobility assist device including a cluster of wheels and a seat, the cluster of wheels and the seat separated by a distance, the distance varying based on a preselected characteristic, the method comprising: receiving an indication that the mobility assistance device will encounter the steep terrain; directing the wheel cluster to maintain contact with the ground; maintaining balance of the mobility assistance device and dynamically adjusting a distance between the seat and the wheel cluster based on the indication; A method comprising: [Brief explanation of the drawings]

[0063] The present teachings may be more readily understood by reference to the following description taken in conjunction with the accompanying drawings.

[0064] [Figure 1A] FIG. 1A is a perspective schematic diagram of a front view of a base of a mobility assistance device of the present teachings. [Figure 1B]FIG. 1B is a perspective schematic diagram of a side view of a wheelchair base of the present teachings. [Figure 1C] FIG. 1C is a perspective schematic view of a wheelchair base of the present teachings, including a battery. [Figure 1D] FIG. 1D is a perspective schematic view of a wheelchair base of the present teachings illustrating a removable battery. [Figure 1E] FIG. 1E is a perspective schematic diagram of an exploded side view of a battery pack of the present teachings. [Figure 1F] FIG. 1F is a perspective schematic view of a gearbox of the present teachings. [Figure 1G] FIG. 1G is a perspective schematic diagram of a lid for an electronic box of the present teachings. [Figure 1H] FIG. 1H is a perspective schematic diagram of a top cap of the present teachings. [Figure 1I] 1I and 1J are perspective schematic views of a section of a gearbox of the present teachings. [Figure 1J] 1I and 1J are perspective schematic views of a section of a gearbox of the present teachings. [Figure 1J-1] FIG. 1J-1 is a detailed perspective view of a spring pin of the present teachings. [Figure 1K] FIG. 1K is a cross-sectional view of a sector gear cross shaft of the present teachings. [Figure 1L] FIG. 1L is a plan view of a seal bead location of the present teachings. [Figure 1M] FIG. 1M is a perspective schematic view of an oil port of a gearbox of the present teachings. [Figure 1N] FIG. 1N is a perspective schematic view of a drive lock kingpin of the present teachings. [Figure 1O] FIG. 10 is a perspective schematic view of a dorsal fastening loop of the present teachings. [Figure 1P] 1P, 1Q, and 1R are perspective schematic views of a skid plate and drive lock kingpin of the present teachings. [Figure 1Q] 1P, 1Q, and 1R are perspective schematic views of a skid plate and drive lock kingpin of the present teachings. [Figure 1R]1P, 1Q, and 1R are perspective schematic views of a skid plate and drive lock kingpin of the present teachings. [Figure 2A] FIG. 2A is a perspective schematic view of gears in a gearbox of the present teachings. [Figure 2B] 2B-2E are perspective and plan views of details of the gears and cluster cross shaft of the present teachings. [Figure 2C] 2B-2E are perspective and plan views of details of the gears and cluster cross shaft of the present teachings. [Figure 2D] 2B-2E are perspective and plan views of details of the gears and cluster cross shaft of the present teachings. [Figure 2E] 2B-2E are perspective and plan views of details of the gears and cluster cross shaft of the present teachings. [Figure 2F] FIG. 2F is a perspective schematic diagram of a cluster cross shaft and a sector gear cross shaft of the present teachings. [Figure 2G] FIG. 2G is a perspective schematic view of details of the gears and sector gear cross shaft of the present teachings. [Figure 2H] FIG. 2H is a perspective schematic view of details of gear and pinion height actuator stage 1 of the present teachings. [Figure 2I] 2I and 2J are plan views of details of the gear and pinion height actuator stage 1 of the present teachings. [Figure 2J] 2I and 2J are plan views of details of the gear and pinion height actuator stage 1 of the present teachings. [Figure 2K] FIG. 2K is a perspective schematic view of a gear and cluster cross shaft of the present teachings. [Figure 2L] FIG. 2L is a perspective schematic view of a pinion gear height actuator stage 2 pinion with a retaining ring of the present teachings. [Figure 2M] FIG. 2M is a perspective schematic view of a shaft pinion cluster rotor stage 1 with an inner ring of the present teachings. [Figure 2N] FIG. 2N is a perspective schematic view of a pinion height actuator shaft stage 1 of the present teachings. [Figure 2O] 2O and 2P are perspective schematic views of a cluster rotor pinion gear stage 2 pinion of the present teachings. [Figure 2P] 2O and 2P are perspective schematic views of a cluster rotor pinion gear stage 2 pinion of the present teachings. [Figure 2Q] FIG. 2Q is a perspective schematic view of a cluster rotor pinion gear stage 3 pinion of the present teachings. [Figure 2R] FIG. 2R is a perspective schematic view of a cluster rotor gear-pinion cross-shaft stage 3 of the present teachings. [Figure 2S] FIG. 2S is a perspective schematic view of a sector gear cross shaft of the present teachings. [Figure 2T] FIG. 2T is a perspective schematic diagram of a pinion gear height actuator stage 3 pinion of the present teachings. [Figure 2U] FIG. 2U is a perspective schematic view of the pinion gear height actuator stage 4 of the present teachings. [Figure 2V] FIG. 2V is a perspective schematic diagram of a second configuration of the pinion gear height actuator stage 4 of the present teachings. [Figure 3A] FIG. 3A is a perspective schematic view of a motor and sector gear cross shaft of the present teachings. [Figure 3B] FIG. 3B is a perspective schematic diagram of a cluster and seat position sensor of the present teachings. [Figure 3C] FIG. 3C is a perspective schematic diagram of a motor and sensor of the present teachings. [Figure 3D] FIG. 3D is a perspective schematic view of a seat / cluster motor of the present teachings. [Figure 3E] FIG. 3E is an exploded perspective view of a seat / cluster motor of the present teachings. [Figure 3F] FIG. 3F is a perspective schematic diagram of a wheel motor of the present teachings. [Figure 3G] FIG. 3G is an exploded perspective view of a wheel motor of the present teachings. [Figure 3H] FIG. 3H is a perspective schematic view of a brake of the present teachings without a brake lever. [Figure 3I]FIG. 3I is a perspective schematic view of a brake with a brake lever of the present teachings. [Figure 3J] FIG. 3J is a perspective schematic view of a mating notch on a gear clamp of the present teachings. [Figure 3K] FIG. 3K is a perspective schematic view of a seat position sensor gear tooth clamp with mating notches of the present teachings. [Figure 3K-1] FIG. 3K-1 is a perspective schematic view of a second configuration of a seat position sensor gear tooth clamp with mating notches of the present teachings. [Figure 3L] FIG. 3L is a perspective schematic diagram of a mating notch of a seat position sensor of the present teachings. [Figure 3M] FIG. 3M is an exploded perspective view of a seat position sensor of the present teachings. [Figure 3N] FIG. 3N is a top view of a seat position sensor of the present teachings. [Figure 3O] FIG. 3O is an exploded perspective view of a cluster position sensor of the present teachings. [Figure 3P] FIG. 3P is a plan view of a cluster position sensor of the present teachings. [Figure 4] FIG. 4 is a perspective schematic view of a caster arm of a caster of the present teachings. [Figure 5A] FIG. 5A is a perspective schematic view of a linkage arm and seat support structure of a gearbox of the present teachings. [Figure 5B] FIG. 5B is a perspective schematic view of a connection feature of a seat support structure of the present teachings. [Figure 5C] FIG. 5C is a perspective schematic view of a seat height linkage stabilizer link of the present teachings. [Figure 5D] FIG. 5D is a perspective schematic diagram of a first view of a seat height linkage lift arm of the present teachings. [Figure 5E] FIG. 5E is a perspective schematic diagram of a second view of a seat height linkage lift arm of the present teachings. [Figure 6A] FIG. 6A is a perspective schematic view of a cluster assembly of the present teachings. [Figure 6B] FIG. 6B is a perspective schematic view of a cluster motor assembly of the present teachings. [Figure 6C] FIG. 6C is a perspective schematic view of a cluster motor assembly with splines of the present teachings. [Figure 6D] FIG. 6D is a perspective schematic view of the gear-pinion cluster rotor stage 3 cross shaft and pinion shaft cluster rotor stage 4 of the present teachings. [Figure 6E] FIG. 6E is a perspective schematic diagram of a pinion shaft cluster rotor stage 4 and a cluster position sensor tooth cluster cross shaft gear diagram of the present teachings. [Figure 6F] FIG. 6F is a perspective schematic view of a gear-pinion cluster rotor stage 3 cross shaft of the present teachings. [Figure 6G] FIG. 6G is a sectioned perspective view of a cross-shaft cluster rotor of the present teachings. [Figure 6H] FIG. 6H is a perspective schematic diagram of a cluster plate interface of the present teachings. [Figure 6I] FIG. 6I is a perspective schematic diagram of a second configuration of a cluster plate interface of the present teachings. [Figure 6J] FIG. 6J is a perspective schematic view of a ring gear of the present teachings. [Figure 6K] FIG. 6K is a perspective schematic view of a cluster housing and gears of the present teachings. [Figure 6L] FIG. 6L is a perspective schematic view of a wheel drive intermediate stage of the present teachings. [Figure 6M] FIG. 6M is a top view of a cluster housing of the present teachings including a sealing bead. [Figure 7A] FIG. 7A is a perspective schematic view of a tire of the present teachings. [Figure 7B] FIG. 7B is a perspective schematic view of a tire assembly of the present teachings. [Figure 7C] FIG. 7C is a perspective schematic view of a dual tire assembly of the present teachings. [Figure 7D] FIG. 7D is a perspective schematic view of a tire of the present teachings. [Figure 7E] FIG. 7E is a perspective schematic view of a wheel of the present teachings. [Figure 7F]FIG. 7F is a perspective schematic view of an attachment base of the present teachings. [Figure 7G] FIG. 7G is a perspective schematic view of an inner split rim of the present teachings. [Figure 7H] FIG. 7H is a perspective schematic view of a hubcap of the present teachings. [Figure 7I] FIG. 7I is a perspective schematic view of a locking pin spring of the present teachings. [Figure 7J] FIG. 7J is a perspective schematic view of a fastener housing of the present teachings. [Figure 7K] FIG. 7K is a perspective schematic view of a locking pin of the present teachings. [Figure 7L] FIG. 7L is a perspective cross-sectional view of a dual tire assembly with a locking pin partially inserted. [Figure 7M] FIG. 7M is a perspective cross-sectional view of the dual tire assembly with the locking pin fully inserted. [Figure 8] FIG. 8 is a diagrammatic representation of a sensor positioning configuration for a mobility assistance device of the present teachings. [Figure 9A] FIG. 9A is a perspective schematic diagram of an exploded view of a manual brake assembly of the present teachings. [Figure 9B] FIG. 9B is a perspective schematic view of a damper of the manual brake assembly of the present teachings. [Figure 9C] FIG. 9C is a perspective schematic view of the damper of the manual brake assembly of the present teachings during operation. [Figure 9D] FIG. 9D is a perspective schematic view of a manual brake release shaft of the present teachings. [Figure 9E] FIG. 9E is a perspective schematic view of a manual brake release bracket of the present teachings. [Figure 9F] FIG. 9F is a perspective schematic view of a manual brake release pivot interface of the present teachings. [Figure 9G] FIG. 9G is a perspective schematic view of a manual brake release spring arm of the present teachings. [Figure 9H] FIG. 9H is a perspective schematic view of a manual brake release shaft arm of the present teachings. [Figure 9I]FIG. 9I is a perspective schematic view of a brake release lever of the present teachings. [Figure 9J] FIG. 9J is a perspective schematic view of a manual brake release assembly of the present teachings. [Figure 9K] FIG. 9K is a perspective schematic view of a hard travel manual brake lever of the present teachings. [Figure 9L] FIG. 9L is an exploded perspective view of a manual brake lever travel stop of the present teachings. [Figure 9M] FIG. 9M is an exploded perspective view of a manual brake lever travel stop of the present teachings. [Figure 9N] FIG. 9N is an exploded top view of a manual brake lever travel stop of the present teachings. [Figure 10A] FIG. 10A is a perspective schematic view of a cable port of the present teachings. [Figure 10B] FIG. 10B is an exploded perspective view of a harness of the present teachings. [Figure 10C] FIG. 10C is a perspective schematic view of a UC port harness of the present teachings. [Figure 10D] FIG. 10D is a perspective schematic view of a charging input port harness of the present teachings. [Figure 10E] FIG. 10E is a perspective schematic view of an accessory port harness of the present teachings. [Figure 11A] 11A-11D are schematic block diagrams of various wiring configurations of the present teachings. [Figure 11B] 11A-11D are schematic block diagrams of various wiring configurations of the present teachings. [Figure 11C] 11A-11D are schematic block diagrams of various wiring configurations of the present teachings. [Figure 11D] 11A-11D are schematic block diagrams of various wiring configurations of the present teachings. [Figure 11E] FIG. 11E is a perspective schematic diagram of a power-off request switch of the present teachings. [Figure 12A] 12A and 12B are perspective schematic views of a first configuration of a UC of the present teachings. [Figure 12B]12A and 12B are perspective schematic views of a first configuration of a UC of the present teachings. [Figure 12C] 12C and 12D are perspective schematic views of a second configuration of a UC of the present teachings. [Figure 12D] 12C and 12D are perspective schematic views of a second configuration of a UC of the present teachings. [Figure 12E] 12E and 12F are perspective schematic views of a third configuration of a UC of the present teachings. [Figure 12F] 12E and 12F are perspective schematic views of a third configuration of a UC of the present teachings. [Figure 12G] FIG. 12G is a perspective schematic view of a forward-facing component of a second configuration of a UC of the present teachings. [Figure 12H] FIG. 12H is a perspective schematic diagram of a joystick of a UC of the present teachings. [Figure 12I] FIG. 12I is an exploded perspective view of a first configuration of a UC of the present teachings. [Figure 12J] FIG. 12J is an exploded perspective view of a first configuration of a UC of the present teachings. [Figure 12K] FIG. 12K is an exploded perspective view of a first configuration of a UC of the present teachings. [Figure 12L] 12L and 12M are perspective schematic views of the upper and lower housings of a first configuration of a UC of the present teachings. [Figure 12M] 12L and 12M are perspective schematic views of the upper and lower housings of a first configuration of a UC of the present teachings. [Figure 12N] FIG. 12N is an exploded perspective view of the thumbwheel component of the lower housing of a third configuration of a UC of the present teachings. [Figure 12O] FIG. 12O is a cross-sectional view of the thumbwheel sensor environmental isolation of the lower housing of a third configuration of a UC of the present teachings. [Figure 12P] FIG. 12P is a perspective schematic diagram of a display cover glass of a UC of the present teachings. [Figure 12Q] FIG. 12Q is a perspective schematic view of a joystick support ring of a UC of the present teachings. [Figure 12R]FIG. 12R is a perspective schematic view of a toggle housing of a UC of the present teachings. [Figure 12S] 12S and 12T are perspective schematic views of a toggle housing of a UC of the present teachings. [Figure 12T] 12S and 12T are perspective schematic views of a toggle housing of a UC of the present teachings. [Figure 12U] 12U and 12V are perspective schematic views of the undercap of the UC of the present teachings. [Figure 12V] 12U and 12V are perspective schematic views of the undercap of the UC of the present teachings. [Figure 12W] 12W and 12X are sectioned and exploded perspective views of an EMI suppression ferrite of a UC of the present teachings. [Figure 12X] 12W and 12X are sectioned and exploded perspective views of an EMI suppression ferrite of a UC of the present teachings. [Figure 12Y] FIG. 12Y is a perspective schematic diagram of a UC-equipped device of the present teachings. [Figure 12Z] FIG. 12Z is ​​a perspective schematic view of a mounting cleat of a UC of the present teachings. [Figure 12AA] FIG. 12AA is a perspective schematic view of a grommet of a UC of the present teachings. [Figure 12BB] 12BB and 12CC are perspective schematic views of a button assembly of a UC of the present teachings. [Figure 12CC] 12BB and 12CC are perspective schematic views of a button assembly of a UC of the present teachings. [Figure 12DD] 12DD and 12EE are perspective schematic diagrams of a toggle module of a UC of the present teachings. [Figure 12EE] 12DD and 12EE are perspective schematic diagrams of a toggle module of a UC of the present teachings. [Figure 13A] 13A and 13B are perspective schematic views of a fourth configuration of a UC of the present teachings. [Figure 13B] 13A and 13B are perspective schematic views of a fourth configuration of a UC of the present teachings. [Figure 13C]FIG. 13C is a perspective schematic view of a UC assist holder of a UC of the present teachings. [Figure 14A] FIG. 14A is a perspective schematic diagram of a UC circuit board of a UC of the present teachings. [Figure 14B] 14B and 14C are schematic block diagrams of the layout of a UC circuit board of a UC of the present teachings. [Figure 14C] 14B and 14C are schematic block diagrams of the layout of a UC circuit board of a UC of the present teachings. [Figure 15A] FIG. 15A is a perspective schematic diagram of an electronic device component board of the present teachings. [Figure 15B] FIG. 15B is an exploded perspective view of a circuit board of the present teachings. [Figure 15C] 15C-15D are perspective schematic diagrams of an IMU assembly of the present teachings. [Figure 15D] 15C-15D are perspective schematic diagrams of an IMU assembly of the present teachings. [Figure 15E] FIG. 15E is a perspective schematic diagram of a first view of an IMU board and EMF shield of the present teachings. [Figure 15F] FIG. 15F is a perspective schematic diagram of a second view of the IMU board and EMF shield of the present teachings. [Figure 15G] FIG. 15G is a perspective schematic diagram of a first configuration of a power controller board of the present teachings. [Figure 15H] FIG. 15H is a perspective schematic diagram of a second configuration of a power controller board of the present teachings. [Figure 15I] 15I-15J are schematic block diagrams of the power supply controller board of the present teachings. [Figure 15J] 15I-15J are schematic block diagrams of the power supply controller board of the present teachings. [Figure 16A] FIG. 16A is a schematic block diagram of an overview of the system of the present teachings. [Figure 16B] FIG. 16B is a schematic block diagram of the electronic components of a mobility assistance device of the present teachings. [Figure 17A]FIG. 17A is a schematic block diagram of a base controller of the present teachings. [Figure 17B] 17B-17C are message flow diagrams for the infrastructure controller of the present teachings. [Figure 17C] 17B-17C are message flow diagrams for the infrastructure controller of the present teachings. [Figure 18A] 18A-18D are schematic block diagrams of a processor of the present teachings. [Figure 18B] 18A-18D are schematic block diagrams of a processor of the present teachings. [Figure 18C] 18A-18D are schematic block diagrams of a processor of the present teachings. [Figure 18D] 18A-18D are schematic block diagrams of a processor of the present teachings. [Figure 19A] FIG. 19A is a schematic block diagram of an inertial measurement unit filter of the present teachings. [Figure 19B] FIG. 19B is a flowchart of a method of the present teachings for filtering gyroscope and acceleration data. [Figure 20] FIG. 20 is a flowchart of a method of the present teachings for field weakening. [Figure 21A] FIG. 21A is a schematic block diagram of a voting processor of the present teachings. [Figure 21B] 21B and 21C are flowcharts of the method of the present teachings for four-stage voting. [Figure 21C] 21B and 21C are flowcharts of the method of the present teachings for four-stage voting. [Figure 21D] 21D and 21G are tabular representations of a voting embodiment of the present teachings. [Figure 21E] (Not specified) [Figure 21F] (Not specified) [Figure 21G] 21D and 21G are tabular representations of a voting embodiment of the present teachings. [Figure 22A]FIG. 22A is a schematic block diagram of allowed mode transitions in one configuration of the present teachings. [Figure 22B] 22B-22D are schematic block diagrams of the control structure for the modes of the system of the present teachings. [Figure 22C] 22B-22D are schematic block diagrams of the control structure for the modes of the system of the present teachings. [Figure 22D] 22B-22D are schematic block diagrams of the control structure for the modes of the system of the present teachings. [Figure 23A] 23A-23K are flow diagrams of operational use of a mobility assistance device of the present teachings. [Figure 23B] 23A-23K are flow diagrams of operational use of a mobility assistance device of the present teachings. [Figure 23C] 23A-23K are flow diagrams of operational use of a mobility assistance device of the present teachings. [Figure 23D] 23A-23K are flow diagrams of operational use of a mobility assistance device of the present teachings. [Figure 23E] 23A-23K are flow diagrams of operational use of a mobility assistance device of the present teachings. [Figure 23F] 23A-23K are flow diagrams of operational use of a mobility assistance device of the present teachings. [Figure 23G] 23A-23K are flow diagrams of operational use of a mobility assistance device of the present teachings. [Figure 23H] 23A-23K are flow diagrams of operational use of a mobility assistance device of the present teachings. [Figure 23I] 23A-23K are flow diagrams of operational use of a mobility assistance device of the present teachings. [Figure 23J] 23A-23K are flow diagrams of operational use of a mobility assistance device of the present teachings. [Figure 23K] 23A-23K are flow diagrams of operational use of a mobility assistance device of the present teachings. [Figure 23L]23L-23X are flow diagrams of a second configuration for operational use of a mobility assistance device of the present teachings. [Figure 23M] 23L-23X are flow diagrams of a second configuration for operational use of a mobility assistance device of the present teachings. [Figure 23N] 23L-23X are flow diagrams of a second configuration for operational use of a mobility assistance device of the present teachings. [Figure 23O] 23L-23X are flow diagrams of a second configuration for operational use of a mobility assistance device of the present teachings. [Figure 23P] 23L-23X are flow diagrams of a second configuration for operational use of a mobility assistance device of the present teachings. [Figure 23Q] 23L-23X are flow diagrams of a second configuration for operational use of a mobility assistance device of the present teachings. [Figure 23R] 23L-23X are flow diagrams of a second configuration for operational use of a mobility assistance device of the present teachings. [Figure 23S] 23L-23X are flow diagrams of a second configuration for operational use of a mobility assistance device of the present teachings. [Figure 23T] 23L-23X are flow diagrams of a second configuration for operational use of a mobility assistance device of the present teachings. [Figure 23U] 23L-23X are flow diagrams of a second configuration for operational use of a mobility assistance device of the present teachings. [Figure 23V] 23L-23X are flow diagrams of a second configuration for operational use of a mobility assistance device of the present teachings. [Figure 23W] 23L-23X are flow diagrams of a second configuration for operational use of a mobility assistance device of the present teachings. [Figure 23X] 23L-23X are flow diagrams of a second configuration for operational use of a mobility assistance device of the present teachings. [Figure 23Y] 23Y-23KK are flow diagrams of a third configuration for operational use of a mobility assistance device of the present teachings. [Figure 23Z]23Y-23KK are flow diagrams of a third configuration for operational use of a mobility assistance device of the present teachings. [Figure 23AA] 23Y-23KK are flow diagrams of a third configuration for operational use of a mobility assistance device of the present teachings. [Figure 23BB] 23Y-23KK are flow diagrams of a third configuration for operational use of a mobility assistance device of the present teachings. [Figure 23CC] 23Y-23KK are flow diagrams of a third configuration for operational use of a mobility assistance device of the present teachings. [Figure 23DD] 23Y-23KK are flow diagrams of a third configuration for operational use of a mobility assistance device of the present teachings. [Figure 23EE] 23Y-23KK are flow diagrams of a third configuration for operational use of a mobility assistance device of the present teachings. [Figure 23FF] 23Y-23KK are flow diagrams of a third configuration for operational use of a mobility assistance device of the present teachings. [Figure 23GG] 23Y-23KK are flow diagrams of a third configuration for operational use of a mobility assistance device of the present teachings. [Figure 23HH] 23Y-23KK are flow diagrams of a third configuration for operational use of a mobility assistance device of the present teachings. [Figure 23II] 23Y-23KK are flow diagrams of a third configuration for operational use of a mobility assistance device of the present teachings. [Figure 23JJ] 23Y-23KK are flow diagrams of a third configuration for operational use of a mobility assistance device of the present teachings. [Figure 23KK] 23Y-23KK are flow diagrams of a third configuration for operational use of a mobility assistance device of the present teachings. [Figure 23LL] 23LL-23VV are flow diagrams of a fourth configuration for operational use of a mobility assistance device of the present teachings. [Figure 23MM] 23LL-23VV are flow diagrams of a fourth configuration for operational use of a mobility assistance device of the present teachings. [Figure 23NN]23LL-23VV are flow diagrams of a fourth configuration for operational use of a mobility assistance device of the present teachings. [Figure 23OO] 23LL-23VV are flow diagrams of a fourth configuration for operational use of a mobility assistance device of the present teachings. [Figure 23PP-1] 23LL-23VV are flow diagrams of a fourth configuration for operational use of a mobility assistance device of the present teachings. [Figure 23PP-2] 23LL-23VV are flow diagrams of a fourth configuration for operational use of a mobility assistance device of the present teachings. [Figure 23QQ] 23LL-23VV are flow diagrams of a fourth configuration for operational use of a mobility assistance device of the present teachings. [Figure 23RR] 23LL-23VV are flow diagrams of a fourth configuration for operational use of a mobility assistance device of the present teachings. [Figure 23SS] 23LL-23VV are flow diagrams of a fourth configuration for operational use of a mobility assistance device of the present teachings. [Figure 23TT] 23LL-23VV are flow diagrams of a fourth configuration for operational use of a mobility assistance device of the present teachings. [Figure 23UU] 23LL-23VV are flow diagrams of a fourth configuration for operational use of a mobility assistance device of the present teachings. [Figure 23VV] 23LL-23VV are flow diagrams of a fourth configuration for operational use of a mobility assistance device of the present teachings. [Figure 24A] 24A and 24B are representations of a graphical user interface of a home screen display of the present teachings. [Figure 24B] 24A and 24B are representations of a graphical user interface of a home screen display of the present teachings. [Figure 24C] 24C and 24D are representations of a graphical user interface of a main menu display of the present teachings. [Figure 24D]24C and 24D are representations of a graphical user interface of a main menu display of the present teachings. [Figure 24E] 24E-24H are representations of graphical user interfaces of selection screen displays of the present teachings. [Figure 24F] 24E-24H are representations of graphical user interfaces of selection screen displays of the present teachings. [Figure 24G] 24E-24H are representations of graphical user interfaces of selection screen displays of the present teachings. [Figure 24H] 24E-24H are representations of graphical user interfaces of selection screen displays of the present teachings. [Figure 24I] 24I and 24J are representations of a graphical user interface of a transition screen display of the present teachings. [Figure 24J] 24I and 24J are representations of a graphical user interface of a transition screen display of the present teachings. [Figure 24K] 24K and 24L are representations of a graphical user interface of a force power off display of the present teachings. [Figure 24L] 24K and 24L are representations of a graphical user interface of a force power off display of the present teachings. [Figure 24M] 24M and 24N are representations of CG compatible screens of the present teachings. [Figure 24N] 24M and 24N are representations of CG compatible screens of the present teachings. [Figure 25A] FIG. 25A is a schematic block diagram of the components of a velocity processor of the present teachings. [Figure 25B] FIG. 25B is a flowchart of the velocity processing method of the present teachings. [Figure 25C] FIG. 25C is a graph of a manual interface response template of the present teachings. [Figure 25D]25D, 25D-1, 25D-2, and 25D-3 are graphs of the interface response of the present teachings based on speed category. [Figure 25D-1] 25D, 25D-1, 25D-2, and 25D-3 are graphs of the interface response of the present teachings based on speed category. [Figure 25D-2] 25D, 25D-1, 25D-2, and 25D-3 are graphs of the interface response of the present teachings based on speed category. [Figure 25D-3] 25D, 25D-1, 25D-2, and 25D-3 are graphs of the interface response of the present teachings based on speed category. [Figure 25E] 25E and 25F are graphical representations of joystick control profiles of the present teachings. [Figure 25F] 25E and 25F are graphical representations of joystick control profiles of the present teachings. [Figure 25G] FIG. 25G is a schematic block diagram of the components of the adaptive rate control processor of the present teachings. [Figure 25H] FIG. 25H is a flowchart of the adaptive speed processing method of the present teachings. [Figure 25I] 25I-25K are diagrammatic illustrations of exemplary uses of adaptive speed control of the present teachings. [Figure 25J] 25I-25K are diagrammatic illustrations of exemplary uses of adaptive speed control of the present teachings. [Figure 25K] 25I-25K are diagrammatic illustrations of exemplary uses of adaptive speed control of the present teachings. [Figure 26A] FIG. 26A is a schematic block diagram of the components of a traction control processor of the present teachings. [Figure 26B] FIG. 26B is a flowchart of a method of traction control processing of the present teachings. [Figure 27A] FIG. 27A is a graphical representation of a comparison of a fall of a mobility assist device of the present teachings versus an uphill climb of a mobility assist device of the present teachings. [Figure 27B]FIG. 27B is a flowchart of a method of anti-tip processing of the present teachings. [Figure 27C] FIG. 27C is a schematic block diagram of an anti-tip controller of the present teachings. [Figure 27D] FIG. 27D is a schematic block diagram of a CG adaptation processor of the present teachings. [Figure 27E] FIG. 27E is a flowchart of a method of CG matching processing of the present teachings. [Figure 28A] FIG. 28A is a schematic block diagram of a weight processor of the present teachings. [Figure 28B] FIG. 28B is a flow chart of a method of weight processing of the present teachings. [Figure 28C] FIG. 28C is a schematic block diagram of a weight-current processor of the present teachings. [Figure 28D] FIG. 28D is a flowchart of a weight-current processing method of the present teachings. [Figure 29A] FIG. 29A is a schematic block diagram of the components of the UCP assist of the present teachings. [Figure 29B] 29B-29C are a flowchart of a method of obstacle detection of the present teachings. [Figure 29C] 29B-29C are a flowchart of a method of obstacle detection of the present teachings. [Figure 29D] FIG. 29D is a schematic block diagram of the obstacle detection components of the present teachings. [Figure 29E] 29E-29H are computer-generated representations of a mobility assistance device configured with sensors. [Figure 29F] 29E-29H are computer-generated representations of a mobility assistance device configured with sensors. [Figure 29G] 29E-29H are computer-generated representations of a mobility assistance device configured with sensors. [Figure 29H] 29E-29H are computer-generated representations of a mobility assistance device configured with sensors. [Figure 29I]FIG. 29I is a flowchart of an improved stair climbing method of the present teachings. [Figure 29J] FIG. 29J is a schematic block diagram of the components of the improved stair climbing system of the present teachings. [Figure 29K] 29K-29L are flowcharts of the door passage method of the present teachings. [Figure 29L] 29K-29L are flowcharts of the door passage method of the present teachings. [Figure 29M] FIG. 29M is a schematic block diagram of the door passage components of the present teachings. [Figure 29N] FIG. 29N is a flowchart of a method of restroom navigation of the present teachings. [Figure 29O] FIG. 29O is a schematic block diagram of the components of the restroom navigation of the present teachings. [Figure 29P] 29P-29Q are flowcharts of the mobile storage method of the present teachings. [Figure 29Q] 29P-29Q are flowcharts of the mobile storage method of the present teachings. [Figure 29R] FIG. 29R is a schematic block diagram of the components of the mobile storage of the present teachings. [Figure 29S] FIG. 29S is a flowchart of a storage / charging method of the present teachings. [Figure 29T] FIG. 29T is a schematic block diagram of the storage / charging components of the present teachings. [Figure 29U] FIG. 29U is a flowchart of the elevator navigation method of the present teachings. [Figure 29V] FIG. 29V is a schematic block diagram of the elevator navigation components of the present teachings. [Figure 30A] FIG. 30A is a table of communication packets exchanged within the MD of the present teachings. [Figure 30B] 30B-30E are tables of communication packet contents of the present teachings. [Figure 30C] 30B-30E are tables of communication packet contents of the present teachings. [Figure 30D] 30B-30E are tables of communication packet contents of the present teachings. [Figure 30E] 30B-30E are tables of communication packet contents of the present teachings. [Figure 31A] FIG. 31A is a schematic block diagram of a telecommunications interface of the present teachings. [Figure 31B] 31B and 31C are packet formats for an exemplary protocol of the present teachings. [Figure 31C] 31B and 31C are packet formats for an exemplary protocol of the present teachings. [Figure 31D] FIG. 31D is a schematic block diagram of a wireless communication system of the present teachings. [Figure 31E] 31E and 31F are bubble format diagrams for wireless communication state transitions of the present teachings. [Figure 31F] 31E and 31F are bubble format diagrams for wireless communication state transitions of the present teachings. [Figure 31G] 31G and 31H are messaging diagrams for wireless communication of the present teachings. [Figure 31H] 31G and 31H are messaging diagrams for wireless communication of the present teachings. [Figure 32A] FIG. 32A is a threat / solution block diagram of possible threats to MD of the present teachings. [Figure 32B] FIG. 32B is a flowchart of a method for obfuscating plain text of the present teachings. [Figure 32C] FIG. 32C is a flowchart of a method for deobfuscating plain text of the present teachings. [Figure 32D] FIG. 32D is a transmitter / receiver communication block diagram of the challenge / response method of the present teachings. [Figure 33] FIG. 33 is a schematic block diagram of the event processing of the present teachings. DETAILED DESCRIPTION OF THE INVENTION

[0065] Mobility assist devices (MDs) of the present teachings can include small, lightweight, and powered vehicles that can provide users with the ability to navigate daily living environments, including the ability to maneuver in enclosed spaces and ascend and descend curbs, stairs, and other obstacles. Operating at an elevated seat height, MDs can improve the quality of life for individuals with mobility impairments by enabling them to traverse rough and challenging terrain. An elevated seat height can provide advantages for daily living activities (e.g., accessing higher shelves) and interacting with others at "eye level" while either stationary or mobile.

[0066] 1A and 1B, a mobility assistance device (MD) of the present teachings includes a base assembly 21514, which may include a central gearbox 21514, an output mechanism, and a wheel cluster assembly 21100 / 21201 (FIG. 6A). Li The central gearbox 21514 can include a central gearbox 21514. The central gearbox 21514 can control the rotation of the assemblies 21100 / 21201 (FIG. 6A), limit reaction, and provide structural integrity to the MD. In some configurations, the central gearbox 21514 can be constructed from a highly durable material that is lightweight, thereby increasing the potential payload the MD can carry and improving the MD's range of motion. The central gearbox 21514 can include drive transmissions for the cluster drive and seat height transmission, and can provide a structural mounting interface for the electronics, two caster assemblies, two wheel cluster assemblies, two sets of seat height arms, and motors and brakes for the two wheel drives. Other components and the seat can be attached to the base assembly, for example, by the use of rails 30081. Li The movable transmission parts can be mounted on the base assembly. RiThe central gearbox 21514 may include a gear train that may provide power, rotate the wheel cluster, and drive the seat height actuator. Li is , can provide structure and mounting points for elements of the four-bar linkage, two drive arms (one on each side of the central gearbox 21514), two stabilizer arms (one on each side of the central gearbox 21514), and seat bracket 24001. Li is , provide electrical and mechanical power to the drive wheels and clusters, and provide seat height actuation. The central gear box 21514 can house the cluster transmission, the seat height actuator transmission, and the electronics. The two wheel cluster assemblies 21100 (FIG. 6A) can be attached to the central gear box 21514. The seat support structure, casters, battery, and optional docking brackets can also be attached to the central gear box 21514. The central gear box 21514 can be constructed to provide EM shielding to the components housed within the central gear box 21514. The central gear box 21514 can be constructed to block electromagnetic energy transmission, for example, can be sealed at its seams with a material that can provide EM shielding, such as, but not limited to, NUSILRTV silicone.

[0067] Continuing with reference to FIGS. 1A and 1B, the MD can adapt to seating configurations through the connection of seating options for lifting and stabilizing arms. The MD can provide power, communication, and structural interfaces for optional features such as, for example, but not limited to, powered seating, lighting, and seating control options. Materials that can be used to construct the MD can include, but are not limited to, aluminum, Delrin, magnesium, plywood, medium-carbon steel, and stainless steel. Active stabilization of the MD can be accomplished by incorporating sensors within the MD that can detect the orientation and rate of change of the MD's orientation, motors that can produce high-power and high-speed servo operation, and a controller that can incorporate information from the sensors and motors and calculate appropriate motor commands to achieve active stability and implement the user's commands. Left and right wheel motors can drive the main wheels on both sides of the device. The front and rear wheels can be coupled to drive together, so that the two left wheels can drive together and the two right wheels can drive together. Turning can be accomplished by driving the left and right motors at different speeds. The cluster motor can rotate the wheel base in a forward / rearward direction. This can allow the MD to remain level while the front wheels are higher or lower than the rear wheels. The cluster motor can be used to keep the device level when going up or down curbs, and can be used to repeatedly rotate the wheel base when going up or down stairs. The seat can be raised and lowered automatically.

[0068] 1C and 1D, the battery packs 70001 can generate heat when charging and discharging. Locating the battery packs 70001 on top of the central housing 21514 and including an air gap 70001-1 between the battery packs 70001 can allow airflow, which can aid in heat dissipation. The battery packs 70001 can be operably coupled to the gearbox lid 21524 at fastener ports 70001-4.

[0069] Referring now to FIG. 1E, a battery 70001 can serve as the primary energy source for the MD. Multiple separate identical batteries 70001 can provide redundant energy supplies to the device. Each battery 70001 can provide a separate power bus from which other components can draw power. Each battery 70001 can provide power to sensors, controllers, and motors through a switching power converter. The battery 70001 can also receive regenerative power from the motor. The batteries 70001 can be replaceable and removable with or without tools. Each battery 70001 can be connected to the MD, for example, but not limited to, via a blind-mating connector. During battery installation, the power terminals of the connector can mate before the battery signal terminals, preventing damage to the battery circuitry. The connector can enable correct connection and inhibit and / or prevent incorrect connection. Each battery 70001 can include a relatively high energy density and relatively low weight cell 29, such as, but not limited to, a rechargeable lithium ion (Li-ION) battery, such as, but not limited to, a cylindrical 18650 battery in a 16s2p arrangement, providing a nominal voltage of about 58V and a capacity of about 5Ah. Each battery can operate within a range of about 50-100V.

[0070] Continuing with reference to FIG. 1E, in some configurations, at least two batteries 70001 must be combined in parallel. These combined packs can form a battery bank. In some fault-tolerant configurations, there can be two independent battery banks (“Bank A” and “Bank B”). In some configurations, an optional third battery can be present within each battery bank. In some configurations, the load can be shared equally across all packs. In some configurations, up to six battery packs can be used on the system at one time. In some configurations, a minimum of four battery packs is required for operation. Two additional batteries can be added for extended range. In some configurations, the energy storage level for these battery packs can be the same as a standard computer battery, enabling transport by commercial aircraft. Installing empty battery packs 70001 can protect unused battery connection ports on the MD and provide a uniform and complete appearance for the MD. In some configurations, the empty battery pack slots can be replaced with storage compartments (not shown) that may store, for example, battery chargers or other items. The enclosure can seal the empty battery opening to the electronics and prevent environmental contamination to the central housing. The battery pack can be protected from damage by wall 21524A.

[0071] Continuing with FIG. 1E, information from a fuel gauge, such as, but not limited to, a TIbq34z100-G1 wide-range fuel gauge, can be provided to the PSC board 50002 (FIG. 15G) via an I2C bus connection. The battery pack 70001 can communicate with the PSC board 50002 (FIG. 15G) and thus with the PBC board 50001 (FIG. 15G). The battery packs 70001 can be mounted in pairs to maintain redundancy. One battery pack 70001 of the pair can be connected to the processor A1 / A2 43A / 43B (FIG. 18C), and the other can be connected to the processor B1 / B2 43C / 43D (FIG. 18D). Thus, if one of the paired battery packs 70001 fails, the other of the pair can remain operational. Additionally, if a pair of battery packs 70001 becomes malfunctioning, one or more other pair of battery packs 70001 can remain operational.

[0072] Continuing with FIG. 1E, the battery controller, which may execute on processor 401 (FIG. 15J), may include, but is not limited to, commands to initialize each battery, run each battery task when a battery is connected, average the task results from each battery, obtain the bus battery voltage that would be experienced by processor A / B 39 / 41 (FIGS. 18C / 18D), obtain the voltage from the ADC channel for the battery currently in use, obtain the battery voltage from the fuel gauge data, compare the voltage from the fuel gauge data with the voltage from the ADC channel, obtain the number of batteries connected, connect battery 70001 to the bus, power the MD, monitor the battery, and check battery temperature. Temperature thresholds that may be reported include, but are not limited to, low, medium, and high battery conditions. The battery controller may check the charge of battery 70001, compare the charge to a threshold, and issue a warning level under a low charge condition. In some configurations, there may be four thresholds: low charge, low charge alert, limited low charge, and minimum charge. The battery controller can check and ensure that the battery 70001 can be charged. In some configurations, the battery 70001 must be at least a certain voltage, for example, but not limited to, approximately 30 V, and must communicate with the PSC50002 (FIG. 15G) to be charged. The battery controller can restore the battery 70001, for example, by pre-charging the battery 70001, if the battery 70001 has been discharged to the point where the battery protection circuitry is enabled. DC power for charging the battery 70001 can be provided by an external AC / DC power supply. The user can be isolated from potential shock hazards by isolating the user from the battery 70001.

[0073] Referring now primarily to FIG. 1F, the central gearbox 21514 can include an electronics box lid 21524 (FIG. 1G), a brake lever 30070 (FIG. 1A), a power-off request switch 60006 (FIG. 1A), fastening ports 257, lift arm control ports 255, caster arm ports 225, cluster ports 261, and a bumper housing 263. The power-off request switch 60006 (FIG. 11E) can be mounted on the front of the gearbox 21514 (FIG. 1A) and can be wired to the PBC board 50001 (FIG. 11A). At least one battery pack 70001 (FIG. 1C) can be mounted on the electronics box lid 21524. Cleats 21534 can enable positioning and securing of the battery pack 70001 (FIG. 1C) at the battery pack lip 70001-2 (FIG. 1E). The connector cavity 21524-1 can include a spout that can protrude from the lid 21524. The connector cavity 21524-1 can include a gasket (not shown), for example, but not limited to, an elastomeric gasket, around the base of the spout. The battery connector 50010 (FIG. 1E) can operably couple the battery 70001 (FIG. 1C) to the electronics of the MD through the connector cavity 21524-1, and pressure on the battery 70001 (FIG. 1C) provided by fasteners mounted in the fastener cavity 70001-4 (FIG. 1D) can be sealed against the gasket in the connector cavity 21524-1 to protect the gears and electronics of the MD from environmental contamination.

[0074] Referring now to FIG. 1G, an electronics enclosure can house the primary stabilization sensor and decision-making system for the MD. The electronics enclosure can protect the contents from electromagnetic interference while containing emissions. The electronics enclosure can inhibit foreign object intrusion while dissipating excess heat generated within the enclosure. The enclosure can be sealed with a cover and environmental gasket. Components within the enclosure that may generate significant amounts of heat can be physically connected to the enclosure frame via a thermally conductive material. The electronics box lid 21524 can include a battery connector opening 201, a formed-in-place gasket (not shown), and a mounting cleat attachment point 205 for accommodating the mounting of the battery pack 70001 (FIG. 1E) onto the electronics box lid 21524. The battery connector opening 201 can include an elongated rectangle that can include a flat gasket. The battery can compress the flat gasket during assembly, and these gaskets can form an environmental seal between the battery and the MD chassis. An in-situ formed gasket (not shown) can seal portions of the central gearbox 21514, which may include gears, motors, and electronics, from intrusion of foreign matter, including fluids. In some configurations, the harnesses 60007 (FIG. 10C), 60008 (FIG. 10D), and 60009 (FIG. 10E) can be connected to sealed panel-mounted connectors to maintain environmental and EMC protection. The harnesses 60007 (FIG. 10C), 60008 (FIG. 10D), and 60009 (FIG. 10E) can be surrounded by glands and / or panel-mounted connectors incorporating flat gaskets or O-rings, which can be impervious to foreign matter. Surfaces within the central gearbox 21514 can be angled so that environmental contamination, if present, can be channeled away from the sensitive components of the MD. The central gearbox top cap housing 30025 (FIG. 1H) can include a hinge 30025-1 (FIG. 1H) and a cable routing guide 30025-2 (FIG. 1H).The cables can be routed between the UC 130 (FIG. 12A) and the central gear box 21514, for example, through routing guides 30025-2, which can avoid entanglement of the cables with the seat, particularly as the seat moves up and down. A hinged cable housing (not shown) can be operably attached to the hinge 30025-1 (FIG. 1H). The hinged cable housing (not shown) can further restrain the cables to avoid entanglement.

[0075] 1I and 1J, the central gearbox 21514 can include a first section enclosure 30020, a second section enclosure 30021, a third section enclosure 30022, and a fourth section enclosure 30023 that can be joined together to form an enclosure for the seat and cluster gear train and an enclosure for the MD's electronics. The sections can be joined together, for example, but not limited to, by an elastomeric bonding material. The bonding material can be applied to the edges of each of the sections, and the sections can be fastened together so that the edges abut and form the enclosure.

[0076] 1K, sector gear cross shaft 21504 can be supported on glass-filled plastic bushings 21504-1, 21504-2, 21504-3, and 21504-4. Each bushing can be supported by one of first section enclosure 30020, second section enclosure 30021, third section enclosure 30022, and fourth section enclosure 30023. The redundant shaft supports can efficiently share the load between the first section enclosure 30020, the second section enclosure 30021, the third section enclosure 30022, and the fourth section enclosure 30023, reducing the load on any one of the first section enclosure 30020, the second section enclosure 30021, the third section enclosure 30022, and the fourth section enclosure 30023 and allowing for a lighter enclosure structure.

[0077] Referring now to FIG. 1L, prior to intermeshing with one of sections 30020-30023, a sealant bead having properties such as, but not limited to, high temperature resistance, acid and alkali resistance, and aging resistance, such as a room temperature vulcanizing silicone bead, can be applied, for example, to perimeter 30023-1.

[0078] Referring now to FIG. 1M, oil port 40056-1, secured by bolt 40056, can be used to add oil to the gear train enclosure. Each shaft that penetrates the housing can be surrounded by an elastomeric lip and / or O-ring seal. An electrical cable harness enclosure exits the central housing. The body The electronics enclosure does so through a leak-proof connector, which may be sealed to the housing with an O-ring. The electronics enclosure is closed by a lid 21524 (FIG. 1F), which may include a peripheral seal that is crimped to the central housing. The electronics enclosure can provide shielding from the transmission of electromagnetic energy into and out of the enclosure. In some configurations, the sealing material that may join the housings together and the gasket that couples the electronics box lid 21524 (FIG. 1G) and central housing can be made from a conductive material to improve the enclosure's ability to shield electromagnetic energy transmission. The electrical connector exiting the central housing can include a printed circuit board with electromagnetic energy shielding circuitry to stop the transmission of electromagnetic energy along a cable that may be held in place by a cable clamp 30116. Each of the central housings 30020 / 30021 / 30022 / 30023 (FIGS. 1I and 1J) can be aligned to the adjacent housing by a spring pin 40008 (FIG. 1J-1) that presses into the adjacent housing.

[0079] Referring now to FIGS. 1N-1R, the skid plate 30026 (FIG. 1R) can protect the underside of the chassis from impacts and scratches. When installed, the skid plate 30026 (FIG. 1R) can accommodate the optional drive lock kingpin 30070-4 (FIGS. 1N and 1P). In some configurations, the skid plate 30026 (FIG. 1R) can be manufactured from a damage-resistant plastic that can be colored to limit the visibility of scrapes and scratches. The skid plate 30026 (FIG. 1R) can provide a barrier against oil if it drips from the central gearbox 21514. When equipped with the optional docking attachment, the MD can be secured for transportation in conjunction with a vehicle-mounted user-actuated restraint system, which may be commercially available, for example. The docking attachment can include, but is not limited to, a docking weld 30700 (FIG. 1P) and a rear stabilizer loop 20700 (FIG. 1O). The docking weld 30700 (FIG. 1P) can be mounted to the main chassis of the MD. The docking weld 30700 (FIG. 1P) can engage with a vehicle-mounted restraint system to provide anchorage for the MD and limit its movement in the event of an accident. The restraint system of the MD can allow the user to remain seated in the MD for transport within the vehicle. The docking weld 30700 (FIG. 1P) can include, but is not limited to, a drive lock kingpin 30700-4 (FIGS. 1N and 1P), a drive lock plate base 30700-2 (FIG. 1P), and a drive lock plate front 30700-3 (FIG. 1P). The docking weld 30700 (FIG. 1P) can optionally be included with the MD and attached to the central gearbox 21514 (FIG. 1N) at the drive lock plate front 30700-3 (FIG. 1P). The drive lock base 30700-2 (FIG. 1P) can include a drive lock base first side 297 (FIG. 1P), which can include the drive lock kingpin 30700-4 (FIG. 1P), and a drive lock base second side 299 (FIG. 1Q), which can be opposite the drive lock base first side 297 (FIG. 1Q) and can be mounted flush with the central gear box 21514 (FIG. 1N).The drive lock plate base 30700-2 (FIG. 1P) can optionally include at least one cavity 295 (FIG. 1Q), which may, for example, allow for weight management of the MD and reduce weight and material costs. The drive lock kingpin 30700-4 can protrude from a first side 297 of the drive lock base and, for example, can interlock with a female connector (not shown) in the vehicle. The drive lock kingpin 30700-4 protrudes from an underside of the MD to provide sufficient clearance to interlock with the female connector (not shown) and can also provide sufficient clearance from the ground to avoid any motion disruption. In some configurations, the drive lock kingpin 30700-4 can, for example, 3.8 cm ( 1.5 inches ) In some configurations, the rear fastening loop 20700 (FIG. 1O) can engage, for example, with a hook (not shown) in the vehicle at the same time, before, or after the drive lock kingpin 30700-4 (FIG. 1R) interlocks with the female connector. 20700 (FIG. 1O), the hook engages with, for example, the back fastening loop. 20700 (FIG. 1O) may include a sensor that can report to the vehicle when the rear fastening loop is engaged. 20700 (FIG. 1O) is not engaged, the vehicle may provide a warning to the user or may not allow the vehicle to move until engagement is reported. In some configurations, the drive lock base plate 30700-2 (FIG. 1P) may include a removable die cutout 30026-1 (FIG. 1R) that may be used to insert and remove the drive lock kingpin 30700-4 at any time. For example, a MD may include a drive lock base plate 30700-2 (FIG. 1P) with a removable die cutout 30026-1 (FIG. 1R). Various types of drive lock kingpins 30700-4 can be adapted to allow for mounting flexibility.

[0080] Referring now to FIG. 2A, the central gearbox wetted section can include a left outer central gearbox housing 30020 (FIG. 2A), a left inner central gearbox housing 30021 (FIG. 2A), and a right inner central gearbox housing 30022 (FIG. 2A), which can include, but are not limited to, seats and cluster gears and shafts, and position sensors.

[0081] 2B-2E, a gear train for the cluster and seat is shown. The cluster drive gear train can include four stages with two outputs. The shaft on the third stage gear can span the base. The final stage gear on each side can provide a mounting surface for the wheel cluster assembly. The central gearbox wetted section can include a cluster drive gear set, which can include a shaft pinion stage 1 cluster rotor 21518 (FIG. 2M), which can itself drive a pinion gear cluster rotor stage 2 pinion 21535 (FIGS. 2O, 2P, 2B), which can drive a cluster rotor pinion gear stage 3 pinion 21536 (FIGS. 2Q, 2B), which can itself drive a cluster rotor gear-pinion cross shaft stage 321537 (FIGS. 2R, 2B), which is connected to left and right cluster cross shafts 30888 and 30888-1 (FIGS. 6D, 2D, and 2E), which can drive a cluster rotor stage 4 ring gear 30891 (FIG. 6D). The left and right cluster ring gears 30891 (FIG. 6D) can be operably coupled to the wheel cluster housing 21100 (FIG. 6A). The cluster drive gear train can include a pinion shaft stage 130617 (FIG. 2D), which can drive a gear cluster stage 130629 (FIG. 2D) and a pinion shaft stage 230628 (FIG. 2D), which in turn can drive a gear cluster stage 230627 (FIG. 2D) and a pinion shaft 30626 (FIG. 2D), which can drive a gear cluster rotor stage 330766 (FIG. 2D) and a cross-shaft cluster rotor 30765 (FIG. 2D). The input shaft of the wheel cluster assembly can be engaged with two gear trains symmetrically mounted about the input shaft. There are two gear reduction stages that transfer power from the input shaft to an output shaft, on which the wheel assembly 21203 (FIG. 1A) can be mounted. The two wheel cluster assemblies can be identical.

[0082] Referring now to Figures 2F-2V, the seat drive transmission gear train can include four stages with two outputs. The shaft on the final stage gear can span the base and provide an interface with the drive arm. The central gearbox wetted section can also include a seat drive gear train, which can include pinion height actuator shaft stage 130618 (Figures 2G, 2N), which can drive pinion gear height actuator stage 221500 (Figure 2H), which can drive gear height actuator stage 230633 (Figure 2T), which can drive gear height actuator stage 330625 (Figure 2U) and pinion height actuator shaft stage 430877 (Figure 2U). Gear height actuator stage 330625 (Figure 2U) can drive pinion height actuator shaft stage 330632 (Figure 2T). The stage 4 pinion gear height actuator 21502 (FIG. 2U) can drive the cross shaft sector gear stage 4 height actuator 30922 (FIG. 2S), which is mounted on the cross shaft sector gear height actuator stage 4 30909 (FIG. 2S), which is operably coupled at 255 to the left and right lift arms 30065 (FIG. 5A). A seat absolute position sensor 21578 (FIG. 3L) can be associated with the cross shaft sector gear height actuator 30909 (FIG. 2S).

[0083] 3A and 3B, the seat motor assembly 21582 (FIG. 3A) and the cluster motor assembly 21583 can be fixedly positioned within the housings 30020, 30021, and 30022. The seat height absolute position sensor 21578 (FIG. 3B) can be operably coupled to the gear tooth rear clamp 30135 (FIG. 3J), which is operably coupled to the rear half gear clamp 30135 (FIG. 3J), and mounted on the sector gear cross shaft 30909 (FIG. 3B).

[0084] Referring now primarily to FIG. 3C , the central gearbox housing 21515 can include mounting areas for seat / cluster brakes, motors, and sensors. Each drive transmission can include a motor, a brake, and a gear transmission. The brakes can be disengaged when power is applied and engaged when power is removed. The seat / cluster motor mounting area can house the motor mounting bottom 30126 (FIGS. 3D and 3E) and motor mounting top 30127 (FIGS. 3D and 3E), the seat / cluster motor assembly 21582 (FIGS. 3D and 3E), the DC motor 70707 (FIG. 3D), and the brake without manual release 70708-2 (FIG. 3H). The wheel motor mounting area can house the wheel motor assembly 21583 (FIGS. 3F and 3G), the motor mounting top 30125, and the brake without manual release 70708-2 (FIG. 3H). In some configurations, the seat and cluster cross shafts, motors, brakes, and motor couplings can include the same or similar components. The motors can provide the primary type of motion on the MD, i.e., the wheels, cluster, and seats. The wheel motors 21583 (FIG. 3F) can drive each wheel transmission. The cluster motor 21582 (FIG. 3D) can drive the cluster transmission. Device safety and reliability requirements may suggest a dual-redundant load-sharing motor configuration. Each motor can have two sets of stator windings mounted in a common housing. Two separate motor drives can be used to power the two sets of stator windings. The power supply for each drive can be a separate battery. This configuration can minimize the impact of any single-point failure in the path from the battery 70001 (FIG. 1E) to the motor output. Each set of stator windings, along with its corresponding segment of the rotor (referred to as a motor half), can contribute approximately equal torque during normal operation. One motor half can be capable of providing the torque required for device operation, and each motor half can include a set of rotor position feedback sensors for commutation.The seat / cluster motor 21582 (FIG. 3D) and wheel motor 21583 (FIG. 3F) can include, but are not limited to, a single-shaft, dual (redundant) stator BLDC motor operating at up to 66 VDC with sinusoidal drive (voltage range 50-66 VDC). The motor can include two 12-V repeaters mounted on an interface board. One repeater can regulate motor activity. In some configurations, there can be three sensor outputs per motor half, with each sensor offset 60° from the next. Sensors can include, for example, but not limited to, Hall sensors. Sensors can be used for commutation and can provide position information for further feedback. The motor can include a dual motor winding, drive, and brake coil configuration. That is, two separate sets of motor windings and two separate motor drives can be utilized to drive one shaft. Similarly, a brake drive can be used to drive two coils for one shaft and engage / disengage the brake. This configuration can allow the system to respond to a single-point failure of the electronics by continuing operation of its motors and brakes until a safe condition can be achieved. The seat and cluster motor shafts are aligned with the seat and cluster drivetrain input shafts by the motor coupling as the motors are installed. The motor shafts are secured in this correct alignment by motor mounting fasteners.

[0085] Continuing with FIG. 3C, the mechanical package of each seat sensor 21578 (FIG. 3M) and cluster sensor 21579 (FIG. 3O) can house two independent electronic sensors that can relay information to the PBC board 50001 (FIG. 15B). Seat position sensor processor A (FIG. 18C) and cluster position sensor processor A (FIG. 18C) receive position information into the A-side electronics, and seat position sensor processor B (FIG. 18D) and cluster position sensor processor B (FIG. 18D) receive position information into the B-side electronics, providing redundant electronics that can enable full system operation even if one side of the electronics fails. The seat and cluster sensors that feed the A- and B-side electronics can be co-located, allowing for measurement of similar mechanical movements. Co-location can enable result comparison and anomaly detection. Absolute seat and cluster position sensors can report seat and cluster positions and can be referenced as a backup position reference each time the MD is powered on. While the MD is powered on, position sensors built into the seat and cluster motors can be used to determine the seat and cluster positions. The seat position sensor upper / lower housings 30138 / 30137 (FIG. 3M) can house the electronic sensor, shaft, and gears of a single-stage gear train that connect the sensor to the sector gear cross shaft assembly 21504 (FIG. 3J) and cluster cross shaft 30765 (FIG. 6D), respectively. The shaft and gears can be molded as a single piece, for example, from plastic, such as a lubricated plastic, which may allow for formation without additional bearing material or lubricant.

[0086] Referring now to FIGS. 3D-3G, the seat / cluster motor 21583 (FIG. 3F) and the wheel motor 21582 (FIG. 3D) can each include at least one thermistor 70025 that can be thermally coupled to the motor. The at least one thermistor 70025 can report temperature data to the A-side and B-side electronics. The temperature data can be used, for example, but not limited to, to reduce power usage to avoid damage to the motor when the motor reaches a preselected threshold temperature. In some configurations, each motor can include two thermistors 70025, one for each redundant half of the motor. The thermistors 70025 can be affixed to a sleeve that can be operably coupled to the laminations that make up the motor body. The thermistors 70025 can enable indirect estimation of motor winding temperature. Temperature data for a particular motor can be routed to a processor associated with the motor. In some configurations, the temperature data can be quantized by an analog-to-digital converter on the processor, if necessary, and the quantized values ​​can be fed into a temperature estimator algorithm. The algorithm can include an empirically derived model of the heat transfer path for each motor, which can account for the power delivered to the windings, the heat flux through the windings and the housing (measured by the thermistor 70025), from the housing to the chassis on which the motor is mounted. The thermal estimator algorithm can use the current flowing through the motor as well as the motor housing (thermistor) temperature to provide estimates of the motor winding temperature and other variables, such as, but not limited to, motor speed. If the motor is rotating at high speed, more heating can occur, for example, due to eddy current losses. If the motor is stalled, current can be concentrated in one phase, increasing the heating rate in that winding. The thermistor signal can be transmitted along a cable between the motor and the PBC50001 (FIG. 15B).In the PBC50001 (FIG. 15B), each motor cable can be split into two connectors: (1) a first connector 50001-1A (FIG. 15B) including pins for the three motor phase wires, and (2) a second connector 50001-1B (FIG. 15B) for the Hall sensors, phase repeater, brake, and thermistor 70025. In some configurations, the first connector 50001-1A (FIG. 15B) can include, but is not limited to, a 4-pin Molex Mega-Fit connector. In some configurations, the second connector 50001-1B (FIG. 15B) can include, but is not limited to, a 10-pin Molex Micro-Fit connector. The MD motor can be thermally welded into the MD housing, which is fastened to the central housing. The thermal weld can provide a thermal conduction path from the motor to the central housing.

[0087] Referring now to Figures 3H and 3I, a separate electromagnetic holding brake can be coupled to each motor. The electromagnetic holding brake can include two electrically isolated coils, each energized by a brake driver within each of the motor drives. The brake can be engaged or disengaged when both of its coils are energized, or disengaged when only one of its coils is energized. The brake can be designed to automatically engage when the unit is turned off or in the event of a total power loss, thus holding position and / or fail-safe. The electromagnetic brake can be used to hold the mobile unit in place when the wheels are not in operation, and similar brakes can hold the cluster and seat in place when not in operation. The brake can be controlled by commands from the platform processor. When the mobile unit is powered off, the brake can automatically engage and prevent the mobile unit from rolling. If the automatic brake is manually disengaged when powered on, the motor drive can activate and hold the mobile unit in place, and the system can report to the user that the wheel brake has been disengaged. If the brake lever is disengaged after power is turned on, a power-off request can be blocked under some circumstances to prevent unintentional rolling of the MD after power is cut off. Automatic brake disengagement can be used to manually push the MD when power is turned off. Each of the four motors driving the right and left wheels, the cluster, and the seat can be coupled to a holding brake. Each brake can be a spring-applied, electromagnetically released brake with dual redundant coils. In some configurations, the motor brakes can include a manual release lever. A brake without the brake lever 70708-2 (FIG. 3H) can include, but is not limited to, a motor interface 590 and a mounting interface 591. In some configurations, the motor interface 590 can include a hexagonal profile that can mate with a hexagonal motor shaft.The brake with brake lever 70708-1 (FIG. 31) can include a mounting interface 591 A, which can include a hexagonal profile 590 A. The brake with brake lever 70708-1 can include a manual brake release lever 592A, which can be operably coupled to a brake release spring arm 30000 (FIG. 9G), which can be operably coupled to a spring 40037 (FIG. 9J).

[0088] 3J-3L, the central gearbox housing 21515 can include at least one absolute seat position sensor 21578 (FIG. 3M), which can be operatively coupled to a seat position sensor gear tooth clamp 30135 (FIG. 3K). The seat position sensor gear tooth clamp 30135 (FIG. 3K) can include embossings 273 (FIG. 3K) to aid in the alignment and orientation of the seat position sensor gear tooth clamp 30135 (FIG. 3K), which is around the cross shaft stage 4 sector gear 21504 and fastened to the rear half gear clamp 30136. The seat position sensor tooth gear 30134 (FIG. 3M) of the absolute seat position sensor 21578 (FIG. 3M) can interlock the seat position sensor tooth gear 30134 (FIG. 3M) and the position sensor gear tooth clamp 30135 (FIG. 3K) as the cross shaft sector gear height actuator 30909 (FIG. 21A-3) moves. The sector cross shaft 30909 (FIG. 3L) can include a hollow shaft that can operably couple the seat drive train to the left and right seat lift arms of the central housing. A fourth-stage seat height sector gear is crimped onto the shaft and is constrained from rotating about the shaft by a wedge connection between the shaft and gear. The left and right lift arms are required to be aligned with each other to ensure that the seat will lift symmetrically. The left and right lift arms are connected in an asymmetrical pattern that can only be assembled in the correct orientation by pins and bolts. This forces the lift arms to be aligned at all times. The seat absolute position sensor 21578 (FIG. 3M) can measure the rotation of the sector gear cross shaft 30909 (FIG. 3L), which connects to and lifts the left and right seat lift drive arms 21301 (FIG. 5D) of the central gear box 21514 (FIG. 1A). The sector gear cross shaft 30909 (FIG. 3J) can be coupled to the seat position sensor 21578 (FIG. 3M) through a single-stage gear train that can rotate through less than 90° and rotate the seat position sensor 21578 (FIG. 3M) through more than 180°, thereby doubling the sensitivity of the seat position measurement.The seat position sensor gear clamp 30136 (FIG. 3J) can be meshingly interlocked with the seat position sensor gear tooth clamp 30135 (FIG. 3K) around the sector gear cross shaft 30909 (FIG. 3J). The interlocked combination can provide a geared interaction with the seat absolute position sensor 21578 (FIG. 3M). The seat absolute position sensor 21578 (FIG. 3M) can be, but is not limited to, a seat position sensor tooth gear. 30134 (FIG. 3M), a Hall sensor 70020 (FIG. 3M), a magnet 70019 (FIG. 3M), a seat position sensor upper plate 30138 (FIG. 3M), and a seat position sensor lower plate 30137 (FIG. 3M). The magnet 70019 (FIG. 3M) can be mounted on the upper plate 30138 (FIG. 3M). The upper plate 30138 (FIG. 3M) can be fixedly mounted on the lower plate 30137 (FIG. 3M).

[0089] Referring now to FIG. 3O, the at least one absolute cluster position sensor 21579 (FIG. 3O) can include a Hall sensor 70020 (FIG. 3O), a cluster position sensor cluster cross shaft gear 30145 (FIG. 6E), and a cluster position tooth gear 30147 (FIG. 3O). The cluster rotator stage 3 cross shaft 21537 (FIG. 2R) can be geared and interfaced with the absolute cluster position sensor 21579 (FIG. 3O) through the cluster position sensor tooth gear 30147 (FIG. 3O). The seat absolute position sensor 21578 (FIG. 3M) can determine the location of the seat support bracket 24001 (FIG. 8B) relative to the central gear box 21514 (FIG. 9). The cluster position sensor 21579 (FIG. 3O) can determine the position of the wheel cluster housing 21100 (FIG. 6A) relative to the central gear box 21514 (FIG. 9). The seat absolute position sensor 21578 (FIG. 3M) and the cluster position sensor 21579 (FIG. 3O) together can determine the position of the seat relative to the wheel cluster assembly 21100 (FIG. 6A). The seat position sensor 21578 (FIG. 3M) and the cluster position sensor 21579 (FIG. 3O) can sense absolute position. The absolute seat position sensor 21578 (FIG. 3M) can sense that the seat has moved since the previous power off / on. If the MD is powered off and the seat or cluster drivetrain moves, the seat and cluster sensors can sense the new location of the seat and cluster relative to the central gearbox 21514 (FIG. 9) when the MD is powered back on. The MD's fully internal sensor system can provide protection for the sensors against mechanical impacts, debris, and water damage.

[0090] Referring now primarily to FIG. 4, the caster wheels 21001 are attached to the central gear box 21514 for use when the seat height is at its lowest position and can support a portion of the MD when the MD is in standard mode 100-1 (FIG. 22A). The caster wheels 21001 can swivel about a vertical axis to allow for changes in direction. The caster wheels 21001 can allow for maneuverability and obstacle traversal. Caster Assembly 21000 (Figure 5A)The caster arm 30031 may include a caster arm 30031 that may be operably connected at a first end to the caster wheel 21001. The caster arm 30031 may include a caster arm shaft 229 that may allow for an operable connection between the caster arm 30031 and the central gear box 21514 at the caster arm port 225. The caster arm 30031 may be secured within the pocket 225 to prevent it from sliding out while allowing for rotation. The pocket 225 may be aligned with a plastic bushing to allow the caster arm 30031 to rotate. The caster spring plate 30044 may be secured to the central gear box 21514. (Figure 5A) The compression spring 40038 can be operably connected to the caster assembly 21000. (Figure 5A) The caster assembly 21000 can provide shock absorption, stability, and continued operation when the caster wheel 21001 encounters an obstacle. The compression spring 40038 can provide suspension to the system when the caster wheel 21001 is in operation. (Figure 5A) may rest on a compression spring 40038, which itself may rest on a caster spring plate 30044. The compression spring 40038 may be attached to the caster spring plate 30044 by a spring cap 30037, a sleeve bushing 40023, and an O-ring 40027. In some configurations, the O-ring 40027-3 may be used as a rebound bumper. The compression spring 40038 may limit the range of rotation of the caster arm 30031, maintaining the caster wheel 21001 in an acceptable location.

[0091] Referring now primarily to FIG. 5A , the user's vertical position can be changed through a seat drive mechanism, which consists of a gearing and four-bar linkage that attaches the seat assembly to a central gearbox 21514. Elements of the four-bar linkage can include, but are not limited to, the central gearbox 21514, two drive arms 30065 (one on each side of the central gearbox), two stabilizer arms 30066 (one on each side), and a seat bracket 30068. The seat drive gearing can include significant reduction and provide torque to both drive arm links to lift the user and seat assembly relative to the central gearbox 21514. Because the central gearbox 21514 acts as the element of the four-bar linkage that drives the seat, it can rotate relative to the ground and maintain the seat angle during seat transitions. Thus, the cluster drive and seat drive can act in tandem during seat transitions. Rotation of the central gearbox 21514 can move the caster assembly 21000, which can move around obstacles such as, for example, but not limited to, curbs. Any type of seat can be used with the MD by attaching the seat to the seat bracket 30068. The lift arm 21301 (FIGS. 5D / 5E) can be attached to a first end of the lift arm. To the department The lift arm 21301 (FIGS. 5D / 5E) can be operably coupled to the seat bracket 30068 at the second end of the lift arm. To the department The lift arm 21301 (FIGS. 5D / 5E) can be operatively coupled to the central gearbox 21514. Movement of the lift arm 21301 (FIGS. 5D / 5E) is transmitted from electronics housed within the central gearbox 21514 to the control port 255. (Figure 1F) The lift arm 21301 (FIGS. 5D / 5E) can be controlled using a signal transmitted through the lift arm 21301 (FIGS. 5D / 5E). The lift arm 21301 (FIGS. 5D / 5E) can be controlled using a tie-down mechanism, which may allow for, for example, but not limited to, fixed installation of the MD in a vehicle. N Can include stabilizer arm 21302( figure 5C) is the first end of the link To the department The stabilizer arm 21302 ( figure 5C) is the second end of the link To the department The stabilizer arm 21302 ( figure 5C) can be controlled by the movement of the lift arm 21301 (FIGS. 5D / 5E). The stabilizer link rest bumper 30055 can smooth ingress and egress for the user of the MD and reduce wear on the gears in the central gearbox with the electronics 21514. In some configurations, the bumper 30055 can rest within the bumper housing 263 and be secured in place by the stabilizer link rest end cap 30073. The lift arm 21301 and stabilizer arm 21302( figure 5C) can rest on the bumper 30055 when the MD is in standard mode. The absolute position of the motor, determined by an absolute position sensor associated with the motor, can determine when the linkage assembly should rest on the bumper 30055. The motor current required to move the linkage can be monitored to determine when the linkage assembly rests on the bumper 30055. When the linkage assembly rests on the bumper 30055, the gear train cannot be exposed to influences that may result from, for example, obstacles encountered by the MD and / or obstacles and vehicle motion encountered by the vehicle carrying the MD.

[0092] 5B, a vehicle tie-down 30069 can be operatively coupled to a seat bracket 30068 to allow the MD to be secured within a motor vehicle. The restraint system of the MD can be designed to allow a user to remain seated within the MD for transport within the vehicle. The seat bracket 30068 can include, but is not limited to, a seat support bracket plate, which can provide an interface between the seat support bracket 30068 and the central gearbox 21514 (FIG. 5A). ToThe seat attachment rails 30081 can be sized according to the seat selected for use. The seat brackets 30068 attach each type of seat to the lift arms 21301 (FIG. 5D) and stabilizer arms 21302 (FIG. 5C). figure 5C). The seat bracket 30068 can allow the seat to be quickly and easily removed, for example, to change seats and to allow for transport and storage.

[0093] Referring now primarily to FIGS. 6A and 6B, the cluster assembly can include a cluster housing 30010 / 30011 (FIG. 6K), a cluster interface pin 30160 (FIG. 6A), and an O-ring 40027-6 (FIG. 6A) that can environmentally isolate the interior of the central gearbox 21514 at the cluster connection. Each cluster assembly can include a two-stage gear train replicated on both the left and right sides of the central gearbox 21514 to simultaneously drive each cluster assembly. Each cluster assembly can independently operate a set of two wheels 21203 (FIG. 6A) on the wheel cluster 21100 (FIG. 6A), thereby providing forward, reverse, and rotational movement of the MD upon command. The cluster assembly can provide structural support for the wheel cluster 21100 (FIG. 6A) and power transmission for the wheels 21203 (FIG. 6A). The cluster assembly includes, but is not limited to, ring gear nut 30016 (FIG. 6B), ring gear 21591 (6J), ring gear seal 30155 (FIG. 6B), cluster interface cover 21510 (FIG. 6C), first configuration cluster plate interface 30014 (FIG. 6I), cluster interface gasket 40027-14 (FIG. 6B), cluster rotor stage 4 pinion shaft 30888 (FIG. 31A4), brake with manual release 70708 (FIG. 31A), and brushless DC servo motor. 5 cm ( 2 inches )The cluster interface assembly may include a stack 21583 (FIG. 3D) and a motor adapter 30124 (FIG. 6B). The second configuration cluster interface plate 30014A (FIG. 6H) can alternatively provide the functionality of the first configuration cluster interface plate 30014 (FIG. 6I). The cluster interface assembly can drive the cluster wheel drive assembly 21100 (FIG. 6A) under the control of the base processor on the base controller board 50001 (FIG. 15B). The cluster interface assembly provides mechanical power to rotate the wheel drive assembly 21100 (FIG. 6A) together, enabling functions that depend on cluster assembly rotation, such as, but not limited to, stair and curb climbing, uneven terrain, seat tilt adjustment, and balance mode. The cluster motor 21583 (FIG. 6B) can supply input torque to the cluster interface assembly. The cluster interface assembly can provide deceleration and deliver the torque required to lift a user seated on the MD when ascending or descending stairs or lifting relative to balance mode 100-3 (FIG. 22B). Power from the cluster motor 21583 (FIG. 6B) is transmitted to the output shaft and can provide the low-speed, high-torque performance required for stair and obstacle navigation. The cluster O-ring 40027-14 (FIG. 6B) can form a three-way seal between the cluster plate 30014 (FIG. 6A), the cluster interface housing cap 30014 (FIG. 6B), and the center housing 21514 (FIG. 6A).

[0094] Continuing with FIG. 6B , the cluster driveline damper 40027-21 can damp oscillations when necessary to keep the cluster driveline steady. For example, when the cluster gear train is keeping the front wheels off the ground in standard mode, the cluster driveline may have difficulty keeping steady using a motor command due to reaction in the driveline. The motor command may generate more correction than necessary and may request a correction in a direction that can lead to oscillation. Oscillations can be damped using additional friction in the cluster driveline. An elastomeric material may be pressed between the cluster output bearing and the cluster interface plate 30014, which can create friction. Alternatively, a less efficient bearing with significant drag, such as a bronze or plastic bushing, may be used.

[0095] Referring primarily to FIG. 6C, the cluster cross shaft 30765 (FIG. 6D) can be operatively coupled to a ring gear 30891, which can rotate the cluster housing 21100 (FIG. 6A). The cluster housings 21100 (FIG. 6A) can each include two wheels 21203 (FIG. 6A) positioned symmetrically about the center of rotation of the cluster housing 21100 (FIG. 6A). In some configurations, the MD can function substantially the same regardless of which wheel 21203 (FIG. 6A) on the cluster housing 21100 (FIG. 6A) is closest to the stationary caster wheel 21001 (FIG. 4). The cluster position sensor 21579 (FIG. 3O) can include a coupling to the cluster cross shaft 30765 (FIG. 6C) with a gear ratio that, based on symmetry, can rotate the cluster position sensor 21579 (FIG. 3O) one revolution for every half revolution of the cluster housing 21100 (FIG. 6A), doubling the resolution of the cluster position sensor 21579 (FIG. 3O). The cluster housing 21100 (FIG. 6A) is symmetric so that for every half revolution, the cluster will function as if one revolution occurred.

[0096] 6C and 6D, a cluster cross shaft 30765 (FIG. 6F), which is part of a cluster gear train, can operably couple a centrally located third stage gear cluster rotor 30766 (FIG. 6F) to a fourth stage 30888 (FIG. 6D) of the gear train, which is mounted on the left and right sides of the central housing 21514 (FIG. 6A) under the cluster interface cap 30014 (FIG. 6C). The cluster cross shaft 30765 (FIG. 6F) can include a hollow shaft 30765-4 (FIG. 6G), which can include a female spline 30765-3 (FIG. 6G). The fourth stage 30888 (FIG. 6D) can include a male spline 30888-1 (FIG. 6C) at one end and a pinion gear 30888-2 (FIG. 6C) at the other end, which is aligned with the teeth of the male spline 30888-1. In this configuration, the teeth of the pinion gear 30888-2 (FIG. 6C) on the fourth stage 30888 (FIG. 6D) are aligned when they are assembled. In some configurations, the splines and gears can include 15 teeth, although other numbers of teeth can be accommodated with the present teachings. The gear alignment can allow the left and right cluster housings to be assembled onto the center housing so that the wheels are aligned. This important alignment allows the MD to rest on all four wheels when driving with the four main drive wheels.

[0097] 6K, the cluster wheel drive 21100 (FIG. 6A) can include, but is not limited to, an outer cluster housing 30011, an input pinion plug assembly 21105, a wheel drive output gear 30165, a wheel drive output shaft 30102, a wheel drive intermediate shaft and pinion spur 30163, a wheel drive intermediate gear 30164, and an inner cluster housing 30010. At least one magnet 40064, captured between housings 30010 / 30011 in magnet housing 40064-1, can be positioned to be exposed to the oil in the cluster housing 21100A and can attract and remove ferrous metal particles from the oil, reducing gear, bearing, and seal wear caused by particles in the oil. The teeth of the input pinion plug 21105 can engage with the wheel drive mid-stage spar 30163, which can engage with the wheel drive output gear 30165. When the drive assembly 21532 (FIG. 6L) rotates, the output stage spar 21533 rotates, which causes the output stage spar shaft to rotate, which can cause the wheels 21203 (FIG. 6A) to rotate. The wheel drive mid-stage spar 30163 (FIG. 6L) can achieve and maintain correct positioning by coupling with a gear wedge 30602 (FIG. 6L) that fits within the shaft cavity of the wheel drive intermediate gear 30164 (FIG. 6L).

[0098] Referring now to FIG. 6M, clamshell housing 21101 A The oil passage includes a seam 21100-1 around the periphery of the housing 2110 1A Stored inside the housing 21101 A The bonding material 21101-2, for example, but not limited to, an elastomeric bonding material, can be used to bond the housing 21101-2 to the environment. 1A Lip and / or O-ring seals may be applied to the mating surfaces of the housing 21101. A The cluster housing 21100A can include an oil port 21101-4 for adding oil.

[0099] Referring now primarily to FIG. 7A , the primary drive wheels can be large enough to allow the MD to overcome obstacles, yet small enough to fit securely onto stair treads. The tire's compliance can reduce vibrations transmitted to the user and loads transmitted to the MD. The primary drive wheels can remain fixed to the MD unless intentional action is taken by the user or technician. The tires can be designed to minimize static buildup during surface traversal / contact. A split-rim wheel pneumatic tire assembly 21203 can be mounted on the MD's cluster assembly 21100 ( FIG. 6A ) to provide the MD with self-propelled locomotion.

[0100] 7B, the split rim wheel-tire assembly 21203 can include, but is not limited to, an outer split rim 30111, a tire 40060 (FIG. 7D), an inner tube 40061, a rim strip 40062, a shielding disk 30113, a shielding disk spacer 30123, and an inner split rim 30112. The pneumatic tire can house the inner tube 40061, which can surround the rim strip 40062. The shielding disk 30113 can be captured between the inner and outer rims of the split rim assembly 21203. The shielding disk 30113 can be preloaded in a preselected shape, for example, to enable fixed positioning. The shielding disk 30113 can protect against foreign object protrusion through the wheel-tire assembly 21203. The shielding disc 30113 can provide a smooth surface that can inhibit foreign object clogging and wheel damage. The shielding disc 30113 can provide an opportunity for customization, for example, custom colors and designs can be selected and provided on the shielding disc 30113. In some configurations, the tire assembly 21203 can accommodate a solid tire, such as, for example, without limitation, a foam-filled tire. Tire selection can be based on characteristics desired by the user, such as durability, smooth ride and egress, and low failure rate.

[0101] 7C through 7M, the main drive wheels 21203 (FIG. 7B) can be configured to accommodate travel over various types of terrain, including, but not limited to, sandy surfaces. In some configurations, the drive wheels 21203 (FIG. 7B), such as the first outer split-rim 21201A (FIG. 7C), can each accommodate a removable second drive wheel 21201B (FIG. 7C). The second drive wheels 21201B (FIG. 7C) can be installed by a user or an assistant seated within the MD. The second drive wheel 21201B (FIG. 7C) can be attached to the first drive wheel 21201A (FIG. 7C) by pressing the second drive wheel 21201B (FIG. 7C) onto the first drive wheel 21201A (FIG. 7C), rotating the second drive wheel 21201B (FIG. 7C), and inserting the locking pin 21201-A4 (FIG. 7K) until engaged. The attachment step can be performed by a user seated in the MD when the user anticipates encountering difficult terrain. The attachment step can also be performed while not seated in the MD. The first drive wheel 21201A (FIG. 7C) can include an attachment base 40062-1 (FIG. 7F), which can provide means for interlocking the first drive wheel 21201A (FIG. 7C) and the second drive wheel 21201B (FIG. 7C). The attachment base 40062-1 (FIG. 7F) can include a locking pin receiver 40062-1B (FIG. 7F) and a retaining lip 30090-1A (FIG. 7E) for twist-lock wheel attachment of the second drive wheel 21201B (FIG. 7C). The second drive wheel 21201B (FIG. 7C) can include a locking pin 21201-A4 (FIG. 7K) that can operably mate with the locking pin receiver 40062-1B (FIG. 7F) of the second drive wheel 21201B (FIG. 7C). The locking pin 21201-A4 (FIG. 7K) can include a spring 21201-A2 (FIG. 71) that can allow access to the locking pin 21201-A4 (FIG. 7K) after the locking pin 21201-A4 (FIG. 7K) is disengaged and can allow for secure locking of the locking pin 21201-A4 (FIG. 7K) when the locking pin 21201-A4 (FIG. 7K) is engaged.The attachment base 40062-1 (FIG. 7F) can include a retaining tang 40062-1A (FIG. 7F) for a twist-lock wheel attachment. The retaining tang 40062-1A (FIG. 7F) can operably couple with a retaining lip 30090-1B (FIG. 7E) of the first drive wheel 21201A (FIG. 7C). In some configurations, the second drive wheel 21201B (FIG. 7C) can receive a hub cap 21201-A1 (FIG. 7H), which can provide an access opening 21201-A1A (FIG. 7H) for a locking pin removal ring 21201-A4A (FIG. 7K). In some configurations, the first drive wheel 21201A (FIG. 7C) and the second drive wheel 21201B (FIG. 7C) can be different or the same size and / or have different or the same tread on the tire 40060.

[0102] Continuing with reference to FIGS. 7C through 7M, in some configurations, the attachment means between the first drive wheel 21201A (FIG. 7C) and the second drive wheel 21201B (FIG. 7C) can include a grooved push-and-turn locking means (not shown) having multiple radially extending tabs and a mounting structure having multiple retention members. In some configurations, the attachment means can include an undercut or male lip (not shown). In some configurations, the attachment means can include features (not shown) on the spokes 30090-1C (FIG. 7E). In some configurations, the attachment means can include a fastener housing 21201-A3 (FIG. 7J) that can be mounted between the hubs 21201-A2 (FIG. 7E) of the second drive wheel 21201B (FIG. 7C) and the first drive wheel 21201A (FIG. 7C). For example, but not limited to, fasteners such as screws or bolts can operably engage the first drive wheel 21201A (FIG. 7C) and the second drive wheel 21201B (FIG. 7C) through cavities in the fastener housing 21201-A3 (FIG. 7J).

[0103] Referring now primarily to FIG. 8 , the MD can be equipped with any number of sensors 147 ( FIG. 16B ) in any configuration. In some configurations, some of the sensors 147 ( FIG. 16B ) can be mounted on the rear of the MD 122 to accomplish specific goals, such as backup safety. A stereo color camera / light 122A, an ultrasonic beam rangefinder 122B, a time-of-flight camera 122D / 122E, and a single-point LIDAR sensor 122F can be mounted to cooperatively detect obstacles behind the MD, for example, but not limited to, the MD. The MD can receive messages that may include information from the cameras and sensors and enable the MD to react to things that may occur outside the user's field of view. The MD can optionally include a reflector 122C, which can be equipped with additional sensors. The stereo color camera / light 122A can be used as a taillight. Other types of cameras and sensors can also be mounted on the MD. Information from the cameras and sensors can be used to enable a smooth transition to balance mode 100-3 (FIG. 3A) by providing information to the MD and enabling the location of obstacles that may impede the transition to balance mode (described herein).

[0104] Referring now primarily to FIG. 9A , a service brake can be used to hold the MD in place by applying a braking force to the wheel drive motor coupling, stopping the wheels from swinging. The brake can function as a retarding brake whenever the device is not moving. The brake can hold the MD when it is powered on or off. A manual brake release lever can be provided so that when power is turned off, the MD can be manually pushed with a reasonable amount of effort. In some configurations, the lever can be located on the front of the base and accessible by either the user or an attendant. In some configurations, the manual release lever can be sensed by a limit switch, which can indicate the position of the manual release lever. The central gearbox 21514 can include brake release components including, but not limited to, a manual brake release bracket 30003 (FIG. 9E), a manual brake release shaft arm 30001 (FIG. 9H), a manual brake release spring arm 30000 (FIG. 9G), a Hall sensor 70020 (FIG. 9A), a surface mounted magnet 70022, a manual brake release cam 30004 (FIG. 9F), and a manual brake release shaft 30002 (FIG. 9D). A brake release lever handle 30070 (FIG. 9I) can activate the manual brake release through the manual brake release shaft 30002 (FIG. 9D). The manual brake release shaft 30002 (FIG. 9D) can be held in place by the manual brake release bracket 30003 (FIG. 9E). The manual brake release shaft 30002 (FIG. 9D) has a tapered end 30002 -2A manual brake release shaft arm 30001 (FIG. 9D) can be included, which can engage with a manual brake release shaft arm 30001 (FIG. 9H), which can be operably connected to a manual brake release cam 30004 (FIG. 9F). The manual brake release cam 30004 (FIG. 9H) can be operably connected to two manual brake release spring arms 30000 (FIG. 9G). The spring arms 30000 can be operably connected to a brake release lever 592A (FIG. 3I). A Hall sensor 70020 (FIG. 9A) can be operably coupled to the PBC board 50001 (FIG. 9I).

[0105] 9B and 9C, the brake release lever handle 30070 (FIG. 91) has a return force, e.g., a spring-loaded force, that pulls it in when it is in the engaged position. A rotational damper 40083 can provide anti-bounce for the lever 30070 (FIG. 91). The rotational damper 40083 can be operably coupled to the brake shaft 30002 (FIG. 9D) through a connecting collar 30007 and a damper actuator arm 30009. The rotational damper 40083 can allow relatively unrestricted movement when the lever 30070 (FIG. 91) is pivoted clockwise from a vertical position in which the brake is engaged to a horizontal position in which the brake is released. When the lever 30070 (FIG. 9I) is pivoted counterclockwise to re-engage the brake, the rotational damper 40083 provides resistance to rotation of the brake shaft 30002 (FIG. 9D), slowing the rate at which the lever 30070 (FIG. 9I) returns to the vertical position and therefore substantially preventing the lever 30070 (FIG. 9I) from bouncing back to the vertical position. The rotational damper 40083 can be operably coupled to the brake assembly stop housing 30003 (FIG. 9E). The damper actuator arm 30009 (FIG. 9B) can be operably coupled to the brake shaft 30002 (FIG. 9D).

[0106] 91, the manual brake release lever 30070 may include a material that, when excessive force is applied, may be damaged before other manual brake release components are damaged. If the manual brake release lever 30070 is damaged, the manual brake release lever 30070 can be replaced without opening the central housing.

[0107] 9J-9N, the manual release brake assembly can include a manual brake release bracket 30003 (FIG. 9E), a manual brake release shaft arm 30001 (FIG. 9H), a manual brake release spring arm 30000 (FIG. 9G), a Hall sensor 70020 (FIG. 9J), a surface-mounted magnet 70022, a manual brake release pivot interface 30004 (FIG. 9F), and a manual brake release shaft 30002 (FIG. 9D). A brake release lever handle 30070 (FIG. 9I) can activate the manual brake release through the manual brake release shaft 30002 (FIG. 9D). The manual brake release shaft 30002 (FIG. 9D) can be held in place by the manual brake release bracket 30003 (FIG. 9E). The manual brake release shaft 30002 (FIG. 9D) can include a tapered end 30002-2A (FIG. 9D), which can engage with a manual brake release shaft arm 30001 (FIG. 9H), which can be operably connected to a manual brake release pivot interface 30004 (FIG. 9F). The manual brake release pivot interface 30004 (FIG. 9F) can be operably coupled to two manual brake release spring arms 30000 (FIG. 15) in fastening cavities 30004A-1 (FIG. 9F) and 30004A-2 (FIG. 9F). The spring arm 30000 (FIG. 9G) can be operably coupled to a brake release lever 592A (FIG. 3I).

[0108] Continuing to refer primarily to FIGS. 9J-9N, the service brake can include, but is not limited to, a travel stop 30005 (FIG. 9K), which can limit movement of the lever 30070 in a clockwise direction from a vertical position to a horizontal position when viewed from the front of the MD. The travel stop 30005 (FIG. 9K) can prevent the lever 30070 (FIG. 9J) from rotating counterclockwise and can assist the operator in releasing and engaging the brake. The travel stop 30005 (FIG. 9K) can be constructed of metal and can be operably coupled to the second brake release shaft 30002 (FIG. 9D). The travel stop 30005 (FIG. 9K) can interface with a feature of the central housing 21515 (FIG. 9A), which can limit the rotation of the shaft 30002-2 (FIG. 9L). The Hall sensor 70020 can sense when the manual brake release is engaged or disengaged. The Hall sensor 70020 can be operably coupled to both the A-side and B-side electronics using a cable / connector 70030, which can mechanically isolate the Hall sensor 70020 from the A-side and B-side electronics. A travel stop 30005 (FIG. 9M) can be operably coupled to the shaft 30002-2 (FIG. 9L) through a fastener 40000-1 (FIG. 9M). The travel stop 30005 can encounter a protrusion 40003-2, which can allow for limited rotation of the shaft 30002-2 (FIG. 9L).

[0109] 10A-10E and 11B, a harness can be mounted at the cable port to straddle the inside and outside of the sealed portion of the central gear box 21514 and can be surrounded by sealing features such as, for example, but not limited to, an O-ring or gasket. The UC port harness 60007 (FIG. 10C) can thread wires extending from the UCP EMI filter 50007 (FIG. 10A), which can connect to the PSC board 50002 (FIG. 11B). The UC port harness 60007 (FIG. 10C) can include a connector to which the cable 60016 (FIG. 10A) can mate, thereby connecting the UCP EMI filter 50007 to the UC130 (FIG. 12A). The charging input port harness 60008 (FIG. 10D) can thread wires extending from the charging input filter 50008 (FIG. 10A), which can connect the PSC board 50002 (FIG. 9I) to a charging means, such as, but not limited to, a charging power supply 70002 (FIGS. 11A-11D), via the charger port 1158 (FIGS. 10A, 11A-11D). The accessory port harness 60009 (FIG. 10E) can thread wires extending from the auxiliary connector filter 50009, which can connect accessory wires to the PSC board 50002. The cable exit point can be protected from impact and environmental contamination by being positioned between the front wall of the MD and the battery 70001 (FIG. 1E). An articulating cable tether 1149 (FIGS. 11A-11D) can protect the cables, route them from the central housing to the seats, and protect the cables from becoming entangled within the lift and / or stabilizer arms.

[0110] 11A-11D, various wiring configurations are shown for connecting the PBC board 50001, PSC board 50002, and battery pack 70001 (FIG. 1E) to the UC 130, charging port 1158, and optional accessories 1150. Acan be connected. The emergency power off request switch 60006 can interface with the electronics box 1146 through a panel mount 1153. The optional accessory DC / DC module 1155 can include, for example, but not limited to, a module that can be plugged into the PSC board 50002. In some configurations, the DC / DC supply 1155 for the optional accessories can be integrated into the PSC board 50002, eliminating the need to open the electronics box 1146 outside of a controlled environment. In some configurations, the charging port 1158 can include solder terminals for a cable to the port. If the transmission means 1151 includes a cable, the cable can be confined by use of a cable carrier 1149, such as, for example, but not limited to, an IGUS Energy Chain Z06-10-018 or Z06-20-028. In some configurations, the electronics box 1146, which may include, but is not limited to, a PBC board 50001 and a PSC board 50002, communicates with the UC 130, optional accessories 1150, through junctions 1157 (FIG. 11A) and communication means 1151. A , and a charging port 1158. In some configurations, a strain relief 1156 (FIG. 11C) can be connected to the electronics box 1146 and UC 130, the charging port 1158, and the optional accessories 1150. Aand the cable. In some configurations, the cable shield can be routed to a fork connector and terminated at a metal electronics box 1146 using, for example, screws (see FIG. 11D). In some configurations, one or more printed circuit boards 1148 (FIG. 11C) can be operably coupled to strain reliefs 1156L, J, and K (FIG. 11C), which can be mounted to the electronics box 1146. The strain reliefs 1156L, J, and K (FIG. 11C) can serve dual roles as environmental seals and can provide channels through which electrical signals or power can pass. The strain reliefs 1156L, J, and K (FIG. 11C) can include, for example, grommets or glands, or can be overmolded and non-separable from the cable. One or more printed circuit boards 1148 (FIG. 11C) can (1) provide a location for connecting to an internal harness between the printed circuit board 1148 (FIG. 11C) and the PSC board 50002, and (2) provide a location for electromagnetic compatibility (EMC) filtering and electrostatic discharge (ESD) protection. EMC filtering and ESD protection can be enabled by connecting the printed circuit board 1148 (FIG. 11C) to a metal electronics box 1146, forming a chassis ground 1147.

[0111] Continuing with reference to FIGS. 11A-11D , the charger port 1158 is where the AC / DC power supply 70002 can be connected to the MD. The AC / DC power supply can be connected to a mains power source via a line cord 60025. The line cord 60025 can be modified to accommodate various wall outlet styles. The charger port 1158 can be separate from the UC 130 ( FIG. 12A ), allowing the charger port 1158 to be positioned in a location that is most accessible to each end user. End users may have different levels of mobility and require the charger port 1158 to be positioned in a personally accessible location. The connector that plugs into the charger port 1158 can be made without a latch to allow ease of access for users with limited hand function. The charger port 1158 can include a USB port for charging external items, such as a cell phone or tablet, with power from the MD. The charger port 1158 can be configured with male pins that operably mate with female pins on the AC / DC power supply. In some configurations, it may be impossible to operate the MD when the charger port 1158 is engaged, regardless of whether the AC / DC power supply is connected to a mains power source.

[0112] 12A and 12B, the user controller (UC) 130 may include, but is not limited to, a control device (e.g., but not limited to, a joystick 70007), a mode selection control, a seat height and tilt / incline control, a display panel, a speed selection control, a power on and off switch, an audible alert and mute capability, and a horn button. In some configurations, use of the horn button is enabled while driving. The UC 130 may include means for preventing unauthorized use of the MD. The UC 130 may be mounted anywhere on the MD. In some configurations, the UC 130 may be mounted on the left or right armrest. The display panel of the UC 130 may include a backlight. In some configurations, the UC 130 can include a joystick 70007 (FIG. 12A), an upper housing 30151, a lower housing 30152, a toggle housing 30157, an undercap 30158, and a button platform 50020 (FIG. 12A) that can enable selection of options through, for example, button presses. Touchscreens, toggle devices, joysticks, thumbwheels, and other user input devices can also be accommodated by the UC 130.

[0113] 12C and 12D, the UC 130-1 in the second configuration can include a toggle platform 70036 (FIG. 12C), which can include, for example, but not limited to, a toggle lever 70036-2 and a toggle switch 70036-1, which can enable option selection. In some configurations, the toggle lever 70036-2 can enable four-way toggle operation (up, down, left, and right), and the toggle switch 70036-1 can enable two-way toggle operation. Other option selection means can replace the button and toggle as needed to accommodate specific obstacles. The UC 130 (FIG. 12A) and the UC 130-1 in the second configuration can include a cable 60026 and a cable connector 60026-1. The cable connector 60026-2 can operably couple to the UC PCB 50004 (FIG. 14A) and provide data and power to each configuration of the UC. Connector 60026-1 can operably couple the UC130 (FIG. 12A) to the board through cable 60016 (FIG. 10A) that mates to circuit board 50007 (FIG. 10B).

[0114] 12E and 12F, the UC130-1A in a third configuration can include a thumbwheel knob 30173, which can be used to adjust the maximum speed of the MD, for example, but not limited to. In some configurations, the thumbwheel knob 30173 can rotate one full revolution without stops. By omitting stops, the position mapping, position change, rotational speed, and function of the thumbwheel knob 30173 can be interpreted in a variety of different ways depending on the system configuration. In some configurations, a user can dial the thumbwheel knob 30173 “up” to request a higher speed gain and “down” to move the MD more slowly. Position change, rather than the absolute position of the thumbwheel knob 30173, can be used to configure the characteristics of the MD. The sensitivity of the thumbwheel knob 30173 can be configurable. For example, a user with sufficient finger strength, sensitivity, and dexterity to roll and / or twist the thumbwheel knob 30173 in small increments can achieve fine adjustment of the thumbwheel knob 30173 and its underlying functionality. Meanwhile, a user with impaired dexterity may adjust the thumbwheel knob 30173 by bumping it against a knuckle or edge of their hand. Thus, in some configurations, a relatively high sensitivity setting may allow the speed gain to vary from minimum to maximum across a 180° progression, for example. In some configurations, a relatively low sensitivity setting may require, for example, each 90° step to traverse the same gain range. Continuously dialing the thumbwheel knob 30173 "up" may eventually result in discontinuous increases in the speed value. Further dialing "up" may be ignored. Dialing the thumbwheel knob 30173 "down" can be detected and the gain value can be immediately decreased, i.e., "rewinding" the ignored upward movement of the thumbwheel knob 30173 may not be required.Because the absolute position of the thumbwheel knob 30173 cannot be a factor in processing input from the thumbwheel knob 30173, gain values ​​can be dynamically configured through changes to the MD, such as, for example, but not limited to, mode changes and power cycles. In some configurations, gain values ​​can revert to default values ​​after a power cycle. In some configurations, gain values ​​can be determined by settings saved during a power down, even if the thumbwheel knob 30173 is moved after a power down.

[0115] Continuing with reference to Figures 12E and 12F, the MD can include various speed settings that can accommodate the situation in which the MD may be placed, for example, but not limited to, when the MD is indoors or outdoors. Speed ​​settings can be associated with joystick movement. For example, a maximum forward speed, which may be appropriate for a particular setting, can be set so that the user cannot go beyond the maximum speed, regardless of how much the joystick is steered. In some configurations, the MD can be configured to ignore joystick movement. The effect of the thumbwheel assembly is to apply gain in addition to the MD's response to joystick movement.

[0116] Continuing with reference to FIGS. 12E and 12F , in some configurations, the thumbwheel knob 30173 can rotate between hard stops of less than one revolution. In some configurations, a change in wheel position can indicate a change in maximum speed. When the MD is powered on, the position of the thumbwheel knob 30173 before powering off can be recalled, and a new maximum speed can be based on the recalled position of the thumbwheel knob 30173 as the thumbwheel knob 30173 is rotated. In some configurations, the sensitivity of the thumbwheel knob 30173 can be adjusted. Depending on the sensitivity adjustment, the rotation of the thumbwheel knob 30173 can adjust the maximum speed from a relatively small amount to a relatively large amount. The thumbwheel knob 30173 is assembled in a blind hole, thus eliminating the need for an environmental seal at the mounting point of the thumbwheel assembly and eliminating a potential point for water, dust, and / or other contaminants to enter the UC housing. Additionally, the thumbwheel mechanism can be cleaned and inspected, and parts can be replaced without accessing the rest of the UC housing. The angle of the shaft of the thumbwheel knob 30173 can be measured by a non-contact Hall effect sensor. Being a non-contact sensor, the Hall effect sensor can have essentially an infinite lifespan. The sensor can provide a voltage corresponding to the rotational position of the thumbwheel. In some configurations, the signal can be processed by an analog-to-digital converter, and the digital result can be further processed. In some configurations, the sensor can directly output a digital signal, which can be communicated to the UC main processor (see FIG. 14C), for example, via I2C. In some configurations, the sensor can be dual redundant.

[0117] 12G, the upper housing 30151A of the third configuration can include, but is not limited to, an LCD display 70040, a button keypad 70035, a joystick 70007, an antenna 50025, a spacer 30181, a joystick support ring 30154, and a display cover glass 30153. In some configurations, the button 70035 can include an under-mounted snap dome (not shown), which can allow a user to sense when the button 70035 is pressed. The antenna 50025 can be mounted within the upper housing 30151A of the third configuration, for example, to enable wireless communication between the UC130-1A of the third configuration (FIG. 12F). The spacer 30181 can separate the LCD display 70040 from other electronics in the UC130-1A of the third configuration (FIG. 12F). The LCD display 70040 can be protected from environmental hazards by a display cover glass 30153. The joystick 70007 can include a connector 70007-1 (FIG. 12H) that can provide power to the joystick 70007 and allow signal transmission from the joystick 70007. In some configurations, the direction of movement of the joystick 70007 can be measured by more than one independent means to allow for redundancy.

[0118] 12I-12K, the UC 130 can include a circuit board 50004, which can be housed and protected by an upper housing 30151 and a lower housing 30152. The UC 130 can include a display cover glass 30153, which can provide visual access to a screen on which options can be presented to a user. The display can be connected to the UC PCB 50004 by a flexible connector 50004-2 (FIG. 14A). An optional EMC shield 50004-3 can protect against ingress and / or egress of electromagnetic interference to / from the UC PCB 50004. A button assembly 50020-A and a toggle switch 70036 can optionally be included. The button and / or toggle can be mounted on a toggle housing 30157, which can be operably connected to the lower housing 30152 and the upper housing 30151 through an undercap 30158. The UC 130 can be mounted on the MD in a variety of ways and locations via the mounting cleat 30106. The UC 130 throughout features environmental isolation, such as, but not limited to, O-rings such as toggle housing ring 130A, grommets such as cable grommet 40028 ( FIG. 12K ), and adhesives to isolate components such as circuit board 50004 from water, dust, and other potential contaminants. In some configurations, the joystick 70007 and speaker 60023 can be commercially available items. For example, but not limited to, a joystick 70007 such as the APEMHF series can include a protective sheath that can be housed by pressure mounting of the protective sheath mounting cavity 30151-3 and joystick support ring 30154.

[0119] 12L, the upper housing 30151 may include ribs 30151-5 that may support the circuit board 50004. The upper housing 30151 may include mounting spacers 30151-4 that provide space for fixed mounting of the joystick 70007 (FIG. 12A). The upper housing 30151 may include a display cavity 30151-2 that may provide a location for visual access for the display screen of the UC130, without limitation. The upper housing 30151 may also include button cavities, such as, without limitation, a power button cavity 30151-6 and a menu button cavity 30151-7. The upper housing 30151 may include a contoured perimeter 30151-1 that may provide a consistent look and feel with other aspects of the MD. The upper housing 30151 can be constructed from, for example, but not limited to, polycarbonate, polycarbonate acrylonitrile butadiene styrene hybrid, or other materials that can meet the strength and weight requirements associated with the UC. The joystick 70007 ( FIG. 12A ) can be mounted within the protective sheath mounting cavity 30151-3 using fastening means such as, for example, a gasket, a support ring 30154 ( FIG. 12Q ), and fasteners such as, for example, but not limited to, screws and fastener holes 30151-X, which can be used to attach the joystick 70007 and support ring 30154 ( FIG. 12Q ) to the upper housing 30151. Mounting the joystick protective sheath can isolate the UC PCB 50004 ( FIG. 14A ) and other sensitive components from the environment. The upper housing 30151 can include molded datums 30151-X2, which can allow for orientation of the joystick 70007 during assembly. In some configurations, the cable reference 30151-X2 can indicate where the joystick cable connector 70007-1 (FIG. 12H) can be positioned.

[0120] Referring now to FIG. 12M, the lower housing 30152 can be joined to the upper housing 30151 (FIG. 12L) at a perimeter geometry 30152-2. The combination of the lower housing 30152 and the upper housing 30151 (FIG. 12L) can house, among other components, the UC PCB 50004 (FIG. 14A), the speaker 60023 (FIG. 12K), the display cover glass 30153 (FIG. 12P), and the joystick support ring 30154 (FIG. 12Q). Environmental isolation features at the joint can include, for example, but are not limited to, gaskets, O-rings, and adhesives. The lower housing 30152 can include an audio access hole 30152-1, which can be located adjacent to the speaker mounting location 30152-6. A commercially available speaker can be mounted within the speaker mounting location 30152-6 and can be fixedly attached to the lower housing 30152 using attachment means such as, but not limited to, adhesive, screws, and hook-and-loop fasteners. The lower housing 30152 can include at least one support post 30152-7 upon which the UC PCB 50004 (FIG. 12I) can rest. The lower housing 30152 can include a connector relief 30152-3 that can provide space within the lower housing 30152 to accommodate, for example, but not limited to, a joystick connector 50004-8 (FIG. 14A) and a power and communication connector 50004-7 (FIG. 14A). The lower housing 30152 can be attached to the MD via fastening means such as, for example, screws, bolts, hook-and-loop fasteners, and adhesive. When screws are used, the lower housing 30152 can include a fastener receiver 30152-5 that can receive a fastener that can attach the toggle housing 30157 (FIG. 12R) to the lower housing 30152. The lower housing 30152 can also include a through guide 30152-4 that can position a fastener, such as, but not limited to, a seal fastener, that can securely connect the lower housing 30152 and the undercap 30158 (FIG. 12K). The seal fastener can provide environmental isolation.In some configurations, the lower housing 30152 can be constructed from, for example, but not limited to, die-cast aluminum, which can provide strength to the structure.

[0121] Referring now to FIG. 12N, the lower housing 30152A of the third configuration can include a thumbwheel geometry 30152-A1, which can accommodate the thumbwheel 30173. The lower housing 30152 can optionally include a framework (not shown) molded into the inner rear surface 30152-9. The framework can increase the strength and resistance to damage of the UC 130 and can also provide a resting location for the UC PCB 50004 (FIG. 12I). The lower housing 30152A can also provide raised posts 30173-XYZ, which can provide chassis ground contacts for the UC PCB 50004, which can be grounded to the base. A chassis ground contact 30173-2 for the cable shield 60031 (FIG. 12V) can tie metal from the lower housing 30152A to metal on the base. Now referring to Figure 12O,The third configuration lower housing 30152A can include thumbwheel-compatible hardware such as, for example, but not limited to, a position sensor, e.g., a magnetic rotary position sensor such as an AMSAS5600 position sensor, that can sense the direction of a magnetic field created by the rotating magnet 40064 as the thumbwheel knob 30173 rotates. The magnetic sensor can be mounted on a flex circuit assembly, which can provide power to and receive information from the magnetic sensor. In some configurations, compatible hardware, including, but not limited to, a bushing 40023, a magnet 40064, a magnet shaft 30171, an O-ring 40027, a retaining nut 30172, and a screw 40003, can operably couple the thumbwheel knob 30173 and the second configuration lower housing 30152A and enable movement of the magnet 40064 to be reliably sensed by the magnetic sensor. The lower housing 30152A can include a cylindrical pocket within its wall in which a bushing 40023 is positioned. The bushing 40023 can provide radial and axial bearing surfaces for the shaft 30171. The shaft 30171 can include a flange upon which an O-ring 40027 is mounted. The shaft 30171 is captured by a retaining threaded nut 30172 that is sized to fit the shaft 30171 and includes a through-hole that is smaller than the flange / O-ring 40027. When assembled, the O-ring 40027 is compressed, which can eliminate axial play and create viscous drag when the shaft 30171 is turned. The thumbwheel knob 30173 is assembled to the shaft 30171 using fastening means such as, for example, but not limited to, low-head fasteners, a simple friction fit, and / or knurling. The shaft 30171 can include a magnet 40064. The magnetization direction creates a vector normal to the axis of the shaft 30171, which can be measured by a Hall Effect sensor. The measurement of the magnetization vector can be provided by the sensor to UC130 (FIG. 12A). UC130 (FIG. 12A) can calculate the relative change in maximum speed based on the magnetization vector direction.In some configurations, at least some parts of the corresponding hardware, such as, but not limited to, the O-ring 40027, can be lubricated with, for example, but not limited to, silicone grease to provide a smooth user experience. In some configurations, a detent can be added to the thumbwheel assembly to provide a click as the thumbwheel knob 30173 is manipulated.

[0122] hey The thumbwheel knob 30173 can pass through the thumbwheel 30173 and can be operably coupled to the magnet shaft 30171. Corresponding hardware geometry can interlock and retain the thumbwheel 30173 to the lower housing 30152A of the second configuration, and in the configuration shown, environmental isolation can be provided to the interior of the UC130 because the shaft does not need to pierce the lower housing 30152A of the second configuration. The geometry of the thumbwheel assembly allows for field inspection and / or replacement without separating the upper housing 30151 (FIG. 12E) from the lower housing 30152A. Notably, the thumbwheel knob 30173 can be replaced if damaged by impact or worn from use. In some configurations, the thumbwheel knob 30173 can be operably coupled to the shaft 30171 by a click-on or press-fit fastening means.

[0123] Referring now to FIG. 12P, the display cover glass 30153 can include a clear opening 30153-1 that can reveal a menu and options display for the user. The dimensions of the clear opening 30153-1 can be different from the display active area, for example, but not limited to, the dimensions of the clear opening 30153-1. The display cover glass 30153 can include a frame 30153-4 that can be masked black with a pressure-sensitive adhesive layer. In some configurations, the display cover glass 30153 can be masked with black paint, and double-sided tape is applied on top of the black mask. The clear, unmasked area 30153-3 can receive ambient light. The UC130 can vary the brightness of the display based on the ambient light. The display cover glass 30153 can include button cavities 30153-5 and 30153-6, which can provide a location for a button keypad 70035. The display cover glass 30153 can include an outward-facing surface 30153-2, which in some configurations can include a coating, which can, for example, reduce glare reflection and / or improve scratch resistance. In some configurations, a space can exist between the material of the cover glass 30153 and the frame 30153-4. The space can include a decorative element, such as, for example, without limitation, a product logo, which can be indelibly printed and / or etched.

[0124] 12Q, the joystick support ring 30154 can include, without limitation, a receiver 30154-3 for receiving a joystick protective sheath and body, and holes / slots 30154-2 for fastening the support ring 30154 to the upper housing 30151 (FIG. 12L). The holes / slots 30154-2 can be sized to accommodate multiple sizes of joysticks 70007 (FIG. 12A). The holes 30154-1 can accommodate connections between components of the UC130 (FIG. 12A), for example. In some configurations, the support ring 30154 can include a pattern of notches 30154-X2 oriented circumferentially relative to the holes 30154-1 and slots 30154-2. The notches 30154-X2 can interface with the ribs 30151-4 (FIG. 12M) in the upper housing 30151 (FIG. 12M) to ensure the correct rotational position of the hole and slot pattern in the support ring 30154 during assembly of the UC130 (FIG. 12A).

[0125] 12R, the toggle housing 30157 can include a pocket 30157-2 that can house a toggle module, such as, but not limited to, a button platform 50020-A (FIG. 12BB). The toggle housing 30157 can include a connector cavity 30157-3 that can accommodate a flexible cable extending from the toggle device. The toggle housing 30157 can include a through-hole 30157-4 that can accommodate a fastening means that can connect components of the UC130 (FIG. 12A) together. The toggle housing 30157 can include a lower housing connector cavity 30157-5 that can provide an opening for the fastening means to engage. The toggle housing 30157 can include seal geometry 30157-6, which can enable mating / sealing between the toggle housing 30157 and the undercap 30158, which can be secured by undercap fastener cavity 30157-8. The toggle housing 30157 can include toggle module fastener cavity 30157-7, which can enable attachment of the toggle module to the toggle housing 30157. The toggle housing 30157 can include fork guide 30157-1, which can provide a guide for the power / communication cable 60031 (FIG. 12X). An O-ring 130B can enable sealing and environmental isolation between the toggle housing 30157 and the lower housing 30152A (FIG. 12N).

[0126] 12S and 12T, the toggle housing second configuration 30157B can allow for mounting of the toggle platform 70036 (FIG. 12T). The toggle housing second configuration 30157B can include a toggle lever support geometry 30157A-1 (FIG. 12S) and a toggle switch support geometry 30157B-1 (FIG. 12S), which can provide support structures for the toggle lever 70036-2 (FIG. 12T) and the toggle switch 70036-1 (FIG. 12T), respectively. The toggle housing second configuration 30157A can include a connector cavity 30157A-3 to accommodate connections between the toggle platform 70036 (FIG. 12T) and the electronic components of the UC130 (FIG. 12A). The toggle housing 30157B can include a pocket 30157-2 that can house a toggle module, such as, but not limited to, a button platform 50020-A (FIG. 12BB). The toggle housing 30157B can include a connector cavity 30157A-3 that can accommodate a flexible cable extending from the toggle device. The toggle housing 30157B can include a through-hole 30157A-4 that can accommodate a fastening means that can connect components of the UC130 (FIG. 12A) together. The toggle housing 30157B can include a lower housing connector cavity 30157A-5 that can provide an opening for the fastening means to engage. The toggle housing 30157B can include seal geometry 30157A-6, which can enable mating / sealing between the toggle housing 30157B and the undercap 30158 (FIG. 12U), which can be secured by undercap fastener cavity 30157A-8. The toggle housing 30157B can include toggle module fastener cavity 30157A-7, which can enable attachment of the toggle module to the toggle housing 30157B. The toggle housing 30157B can include fork guide 30157A-1, which can provide a guide for the power / communication cable 60031 (FIG. 12X). An O-ring (not shown) can enable sealing and environmental isolation between the toggle housing 30157B and the lower housing 30152A (FIG. 12N).The toggle lever 70036-2 (FIG. 12T) and toggle switch 70036-1 (FIG. 12T) can be positioned and sized to accommodate users with various hand geometries. In particular, the toggle lever 70036-2 (FIG. 12T) can be spaced from the toggle switch 70036-1 (FIG. 12T) by approximately 25-50 mm. The toggle lever 70036-2 (FIG. 12T) can have rounded edges, its top can be slightly convex and generally horizontal, a measurement across its top can be 10-14 mm, and a height of approximately 19-23 mm. The toggle switch 70036-1 (FIG. 12T) can be approximately 26-30 mm long, 10-14 mm wide, and 13-17 mm high. Toggle lever 70036-2 (FIG. 12T) and toggle switch 70036-1 (FIG. 12T) can be positioned at an angle of 15° to 45° relative to joystick 70007 (FIG. 12K).

[0127] 12U, the undercap 30158 can include through fastening holes 30158-1, which can accommodate fastening means for operably coupling to components of the UC130 (FIG. 12A). The undercap 30158 can include grommet cavities 30158-2, which can house grommets 40028, which can environmentally seal the cable entry point. The undercap 30158 can include mounting cleat surfaces 30158-5, which can provide connection points for mounting cleats 30106 (FIG. 12Z). The undercap 30158 can include fastener receptacles 30158-4, which can enable fastening of the undercap 30158 to the toggle housing 30157. The undercap 30158 can include relief cuts 30158-3 for toggle module fasteners. The undercap 30158 can house a gasket 130A, which can environmentally seal the undercap 30158 to the toggle housing 30157.

[0128] 12V-12X, the undercap 30158-1 of the second configuration can include, but is not limited to, an EMI suppression ferrite 70041 and a ferrite retainer 30174. The ferrite retainer 30174 can be operably coupled to the undercap 30158-1 of the second configuration through mounting features 30158-3 (FIG. 12X) and posts 30158-2 (FIG. 12X). The retainer 30174 can be affixed to the undercap 30158 by heat staking the posts 30158-2 (FIG. 12X). In some configurations, the ferrite retainer 30174 can be affixed to the undercap 30158 using threaded fasteners, adhesive, and / or snap features. In some configurations, when the cable 60031 is threaded through the ferrite retainer 30174, the EMI suppression ferrite 70041 can protect the UC 130 from EMI emissions emanating from the cable 60031, which may house the power and cable connections for the UC 130. The shielding 60031-4 can extend from the cable 60031 and connect to a feature of the housing 30152 at connector 60031-3. The metal barrel 60031-1 can allow the shielding to continue down to the base.

[0129] 12C, the UC mounting device 16074 can enable the UC 130 (FIG. 12A) to be fixedly mounted to the MD using any device that can accommodate the stem 16160A, stem split mating portion 16164, and a conventional seat mounted on the MD through operative coupling with the seat bracket 24001 (FIG. 1A). The fastening orifice 162-672 can provide a means for fixedly mounting the device 16074 to the MD. The mounting device 16074 can include a rib 16177 that protrudes from the mounting body 16160 and can accommodate the UC mounting feature 30158 (FIG. 12B). The UC 130 (FIG. 12A) can be operatively coupled to the mounting device 16074 by sliding the mounting cleat 30106 (FIG. 12Z) between the rib 16177 and the mounting body 16160. The release lever 16161 can work in conjunction with a spring-loaded release knob 16162 to allow for secure fastening and easy release of the UC 130 to / from the mounting device 16074.

[0130] 12Z, the mounting cleat 30106 can enable mounting of the UC 130 (FIG. 12A) onto an MD, e.g., an armrest, by, for example, a mounting device 16074 (FIG. 12Y). The mounting cleat 30106 can include an engagement lip 30106-3, which can include a geometry that can enable sliding and locking engagement of the mounting cleat 30106 with a receiver, for example, by depressing a latch button until the UC 130 (FIG. 12A) is properly positioned. In that position, the latch button can protrude into the button cavity 30106-1, thereby locking the UC 130 (FIG. 12A) in place. The lip 30106-4 of the mounting cleat 30106 can fit within the receiver. The mounting cleat 30106 can include a fastening cavity for fastening the mounting cleat 30106 to a mounting cleat surface 30158-5 (FIG. 14A).

[0131] 12AA, grommet 40028-1 can provide an environmental seal surrounding cable 60031 (FIG. 12X). Grommet 40028-1 can rest within grommet cavity 30158-2 (FIG. 12U), with reduced diameter portion 40028-1B captured by the geometry of grommet cavity 30158-2 (FIG. 12U). Cable 60031 (FIG. 12X) can traverse grommet 40028-1 from cable inlet 40028-1A to cable outlet 40028-1C. In some configurations, cable grommet 40028-1 can provide strain relief to cable 60031 (FIG. 12X). Strain relief can prevent damage when cable 60026 is bent or pulled. In some configurations, the cable grommet 40028-1 can be an integral overmolded feature with the cable 60031 (FIG. 12X).

[0132] 12BB and 12CC, the button assembly 50020-A can enable button option entry in the UC 130 (FIG. 12A). The button assembly 50020-A can include a button 50020-A1, for example, but not limited to, a momentary push button, which can be mounted on a button circuit board 50020-A9. The button 50020-A1 can be operably coupled to the button circuit board 50020-A9, which can include a cable connector 50020-A2, which can accommodate, for example, but not limited to, a flexible cable. The button assembly 50020-A can include a spacer plate 50020-S (FIG. 12CC), which can provide a cavity 50020-S1 (FIG. 12CC) for the button 50020-A1. A coverlay (not shown), which provides a graphic and environmental seal, can cover the button 50020-A1.

[0133] 12DD and 12EE, the toggle platform 70036 can include a toggle lever 70036-2 (FIG. 12T), a toggle switch 70036-1 (FIG. 12T), and a toggle mounting means 70036-3 for mounting the toggle platform 70036 on the second configuration 30157A of the toggle housing. The toggle mounting means 70036-3 can be adjacent to the toggle lever support geometry 30157A-2 (FIG. 12U). In some configurations, a low-profile toggle module 70036A (FIG. 12GG) can be included that includes a D-pad 70036A-2 (FIG. 12EE) in place of the toggle lever 70036-2 (FIG. 12DD) and a rocker switch 70036A-1 (FIG. 12EE) in place of the toggle switch 70036-1 (FIG. 12DD). In some configurations, the toggle lever 70036-2 (FIG. 12DD) can be replaced by two two-way toggles (not shown), which can be similar to the controls for power seat tilt and recline. The resulting module can include three two-way toggles.

[0134] Referring primarily to FIG. 13A , the UC holder 133A can house manual and visual interfaces, such as a joystick, display, and associated electronics. In some configurations, the UC assist holder 145A can be attached to the visual / manual interface holder 145C without tools. The UC assist holder 145A can include electronics that can interface with the processor 100 ( FIG. 16B ) and process data from sensors 122A ( FIG. 8 ), 122B ( FIG. 8 ), 122C ( FIG. 8 ), 122D ( FIG. 8 ), 122E ( FIG. 8 ), and 122F ( FIG. 8 ). Any of these sensors can include, but are not limited to, a TEXAS INSTRUMENTS OPT8241 time-of-flight sensor or any device that can provide a three-dimensional location of data sensed by the sensor. The UC assist holder 145A can be positioned anywhere on the MD and need not be limited to being mounted on the visual / manual interface holder 145C.

[0135] Referring now primarily to FIG. 13B , manual / visual interface holder 145C can include, but is not limited to, a visual interface viewing window 137A and a manual interface mounting cavity 133B available on a first side 133E of manual / visual interface holder 145C. Connector 133C is provided on a second side 133D of manual / visual interface holder 145C to connect manual / visual interface holder 145C to UC assist holder 145A ( FIG. 13C ). Any of viewing window 137A, manual interface mounting cavity 133B, and connector 133C can be located on any portion of manual / visual interface holder 145C or can be completely absent. Manual / visual interface holder 145C, visual interface viewing window 137A ( FIG. 13B ), manual interface mounting cavity 133B, and connector 133C can be any size. Manual / visual interface holder 145C can be constructed from any material suitable for mounting visual interface viewing window 137A, manual interface mounting cavity 133B, and connector 133C. Angle 145M can be associated with various orientations of UC holder 133A and therefore can be various values. UC holder 133A can have a fixed orientation or can be hinged.

[0136] 13C , UC assist holder 145A includes, but is not limited to, filter cavity 136G and lens cavity 136F, which can provide visibility to, for example, but not limited to, a time-of-flight sensor optical filter and lens, such as, for example, but not limited to, a TEXAS INSTRUMENTS OPT8241 3D time-of-flight sensor. UC assist holder 145A can be any shape and size and can be constructed from any material, depending on the mounting location on the MD and, for example, the sensor, processor, and power supply provided within UC assist holder 145A. The rounded edges on cavities 136G and 136F and holder 145A can be replaced by edges of any shape.

[0137] 14A-14C, the UC board 50004 can provide electronics and connectors and control the activity of the UC 130 (FIG. 12A). The UC board 50004 can include a circuit board 50004-9, on which connectors and ICs can be mounted. For example, a joystick connector 50004-8, a power and communication connector 50004-7, a toggle connector 50004-5, a thumbwheel connector 50004-4, a speaker connector 50004-6, and a display connector 50004-2 can be included on the mounting board 50004-9. In some configurations, the UC board 50004 can include an ambient light sensor 50004-X (FIG. 14A), the signal from which can be used to vary the brightness and contrast of the display for viewing in indoor and outdoor environments. An EMC shield 50004-3 can provide EMC protection to the UC board 50004. The connection 50004-1 to the wireless antenna 50025 (FIG. 12H) can include, for example, but not limited to, a spring contact. The button snap domes 50004-10 can accommodate, for example, button press activation. In some configurations, the button snap domes 50004-10 can each be associated with backlighting, for example, but not limited to, an LED. Toggle switches and toggle levers can be accommodated as well. The UC board 50004 can process data transmitted to / from the user, the PBC board 50001 (FIGS. 15A and 15B), the PSC board 50002 (FIG. 15G), and the wireless antenna. The UC board 50004 can perform filtering of incoming data and enable the transitions and workflows described in FIGS. 23A-23KK. The UC board 50004 may include, but is not limited to, a wireless transceiver, which may include, for example, but is not limited to, a processor and a transceiver that may support wireless communication using the BLUETOOTH® low energy protocol. The wireless transceiver may include, for example, but is not limited to, a Nordic Semiconductor nRF51422 chip.

[0138] Referring now to FIGS. 15A and 15B, the central gearbox 21514 can include a PSC board 50002 and a PBC stack. The PSC board 50002's electronics can manage power and provide power to the PBC board 50001, which in turn provides power to the MD's motors. The PBC board 50001 can include redundant computers and electronics, whose responsibilities include processing inertial sensor data and calculating motor commands used to control the MD. The electronics for the PBC board 50001 can interface with at least one inertial measurement unit (IMU) 50003 (FIG. 15B) and the UC 130 (FIG. 12A). The PBC board 50001 can include redundant processors, which can be physically separated from each other and have isolation barriers on their interconnections, increasing the robustness of the redundant architecture. Active redundancy can enable conflict resolution during abnormal conditions through voting on actuator commands and other critical data. In some configurations, sensors, underlying processors, and power buses can be physically duplicated within the MD. Sensor inputs, processor outputs, and motor commands from this redundant architecture can be cross-monitored and compared to determine whether all signals are within acceptable tolerances. During normal operation, all signals "match" (within acceptable tolerances), and full functionality of the MD is available to the user. If any one set of these signals is not within the range of the other three, the MD can ignore the data from the non-matching set and continue operation using data from the remaining sensor / processor string. Upon loss of redundancy, an abnormal condition can be identified, and the user can be alerted, for example, via visual and audible signals. For redundancy, the PBC and PSC can each include an "A" side and a "B" side. The PBC "A" side can be divided into "A1" and "A2" quadrants, which can be powered by the PSC "A" side.The PBC "B" side can be divided into "B1" and "B2" quadrants, which can be powered by the PSC "B" side. The IMU can include, for example, four inertial sensors, each of which can be directly mapped to one of the PBC quadrants.

[0139] Continuing with reference to FIGS. 15A and 15B, load-sharing redundancy can be used for power amplifiers, high-voltage power buses, and primary actuators to size motors and batteries for normal, fault-free conditions and to enable higher-stress, short-duration operation during system faults. Load-sharing redundancy can enable lighter-weight, higher-performance fault-tolerant systems than other redundancy approaches. The MD can include multiple separate battery packs 70001 (FIG. 1E). Multiple battery packs 70001 (FIG. 1E) dedicated to each PBC side can provide redundancy so that battery failure conditions can be mitigated. Redundant load-sharing components can be kept separate throughout the system, minimizing the chance that a failure on one side will cause a cascading failure on the other side. Power delivery components (battery packs 70001 (FIG. 1E), wiring, motor drive circuitry, and motor) can be sized to deliver sufficient power to keep users safe while meeting system performance requirements.

[0140] Continuing with reference to FIGS. 15A and 15B, the MD electronics and motors generate heat, which can be dissipated to prevent overheating of the MD. In some configurations, the components of the PCB board 50001 can operate over a temperature range of -25°C to +80°C. The heat spreader 30050 can include a heat spreader plate 30050 and at least one standoff 30052 (FIG. 15B) that can penetrate holes in the base controller board 50001 and support an inertial measurement unit (IMU) assembly 50003 (FIG. 15D). The heat spreader plate 3005 0can be operably connected to the central housing and the MD circuit board through, for example, a thin, electrically insulating material, which can provide a thermal conduction path for heat from the electronics to the central housing. In some configurations, metal-to-metal contact between the heat spreader 30050 and mounting features on the housings 30020-30023 can dissipate heat. The standoffs 30052 (FIG. 15B), along with the standoff grommets 30187 (FIG. 15C), can isolate the IMU assembly from vibrations of the base controller board 50001 and the heat spreader 30050, which may result from vibrations throughout the base. The thermal management system of the present teachings can include a bar 30114 (FIG. 15B) mounted on the heat spreader 30050 but not touching the PBC board 50001, copper areas on the PBC board 50001, and thermal gap pads that provide thermal conductivity between the PBC board 50001 and the heat spreader 30050.

[0141] 15B, the IMU mounted on the heat spreader 30050 can include a soft hardness grommet 30187 (FIG. 15C) that can dampen vibrations and a flex cable 50028-9B (FIG. 15C) that can provide electrical connection to the PCB board 50001. The IMU sensors can be isolated from vibrations generated by the MD's seat, cluster, and wheel drivetrain by mechanically isolating the IMU PCB 50003 (FIG. 15E) on which the sensors 608 (FIG. 15E) are mounted. The IMU assembly can be mounted on at least one elastomeric grommet 30187 (FIG. 15C), which can be attached to at least one post 30052 fastened to the heat spreader plate 30050. The at least one grommet 30187 (FIG. 15C) can include low hardness and damping capabilities, which can limit the transmission of vibrations from the MD to the IMU. The flex circuit cable 50028-9B can be compliant and cannot transmit significant vibrations to the IMU assembly.

[0142] Continuing with reference to FIG. 15B , the magnetic flux shield 30008 can protect the electronics on the PBC board 50001 from magnetic signals from the manual brake release position sensor 70020 ( FIG. 9J ). The magnetic flux shield 30008 can include a ferrous metal and can be operably coupled to the heat spreader assembly 30050 between the manual brake release position sensor 70020 ( FIG. 9J ) and the PBC board 50001. The ferrous metal can contain and redirect the magnetic flux of the manual brake release position sensor 70020 ( FIG. 9J ), substantially preventing interference with the electronics on the PBC board 50001. Possibly, to increase the overall reliability of the MD, the cable can utilize a connector having a latching mechanism.

[0143] 15C-15D, the IMU assembly 50003 may include a main board 50003B (FIG. 15D), which may include, but is not limited to, the inertial sensor 608 (FIG. 15D) and the memory 610 (FIG. 15D). The IMU assembly 50003 may include at least one grommet 30187 (FIG. 15C), which may dampen vibrations and maintain stability of the inertial sensor 608, and a rigid flex circuit 50028-9B, which may connect the IMU assembly 50003 to the PBC board 50001 (FIG. 15B) to reduce vibration transmission. The rigid flex circuit 50028-9B may include a stiffener 50028-9S, which may promote a sturdy connection. The rigid flex circuit 50028-9B may include a bend, which may split the rigid flex circuit cable 50028-9B into two portions, which may provide a sensor interface and a connector interface. At least one grommet 30187 (FIG. 15C) can extend through the main board 50003 (FIG. 15B) in cavity 608A (FIG. 15D) and through similar cavities in the optional IMU shield 70015 (FIG. 15C) and PBC board 50001 (FIG. 15B) and can operably couple with standoffs 30052 (FIG. 15B). Other geometric shapes of rigid flex circuit cables 50028-9B (FIG. 15C) are also possible, as are other connector patterns and grommet locations.

[0144] Continuing with reference to FIGS. 15C-15D , the at least one inertial sensor 608 can include, for example, but not limited to, an ST Microelectronics LSM330DLC IMU. The IMU assembly 50003 can include an IMU PCB 50003B, which can accommodate standoffs 30052 ( FIG. 15B ) to allow for elevation and cushion mounting of the IMU PCB 50003B above the PCB board 50001. The IMU assembly 50003 can include features to allow for mounting an IMU shield 70015 ( FIG. 15C ) onto the IMU PCB 50003B. The optional IMU shield 70015 can protect the inertial sensor 608 ( FIG. 15D ) from possible interference, including, but not limited to, EM interference from the PCB board 50001 ( FIG. 15B ) and / or the PSC board 50002 ( FIG. 15G ). The IMU PCB 50003B may receive / transmit signals to / from the inertial sensor 608 to / from the PCB board 50001 (FIG. 15B) through connector 609. B(FIG. 15F). The inertial sensors 608 (FIG. 15D) can be mounted on the IMU PCB 50003B, which can allow the IMU assembly 50003 to be calibrated separately from the rest of the MD. The IMU PCB 50003B can provide mounting for memory 610 (FIG. 15D), which can hold, for example, calibration data. The non-volatile memory 610 (FIG. 15D) can include, for example, but not limited to, microchip 25AA320AT-I / MNY. Storage of calibration data can allow IMU assemblies 50003 from multiple systems to be calibrated in a single batch and installed without any additional calibration. As sensor technology changes, the inertial sensors 608 (FIG. 15D) can be updated with the latest available sensors in relative electronics design isolation because the IMU assembly 50003 can be relatively isolated from the PCB board 50001. The inertial sensors 608 can be positioned at angles relative to one another. The angular positioning can improve the accuracy of the data received from the inertial sensors 608. Inertial information, such as pitch angle or yaw rate, that may rely entirely on one sensing axis of one inertial sensor 608 can be spread across the two sensing axes of the angled inertial sensors. In some configurations, two inertial sensors 608 can be positioned at a 45° angle from two other inertial sensors 608. In some configurations, the angled inertial sensors 608 can alternate locations with the non-angled inertial sensors 608.

[0145] 15E and 15F, the second configuration IMU assembly 50003A can include at least one inertial sensor 608. The second configuration IMU assembly 50003A can include a second configuration IMU PCB 50003A-1, which can accommodate standoffs 30052 (FIG. 15B) to allow elevated and cushion mounting of the second configuration IMU PCB 50003A-1 above the PCB board 50001. The second configuration IMU assembly 50003A can include features to allow an IMU shield 70015 to be mounted on the second configuration IMU PCB 50003A. The optional IMU shield 70015 can protect the inertial sensor 608 from possible interference, including, but not limited to, EM interference from the PCB board 50001 and / or the PSC board 50002 (FIG. 15G). The IMU PCB 50003A in the second configuration has a connector 609 that can receive / transmit signals to / from the inertial sensor 608 to / from the PCB board 50001 (FIG. 15B). B (FIG. 15F). The inertial sensors 608 (FIG. 15E) can be mounted on the second configuration IMU PCB 50003A. The second configuration IMU PCB 50003A can provide a mount for memory 610 (FIG. 15E), which can hold, for example, calibration data.

[0146] 15G and 15H, the PSC board 50002 may include a connector 277 (FIG. 15G) that may enable a battery 70001 (FIG. 1E) to provide power to the PSC board 50002. The connector 277 may include, for example, contacts and a circuit board mounting means, such as, but not limited to, MOLEXMLX44068-0059. The PSC board 50002 may include at least one microcontroller 401 and may include at least one bumper 30054 / 30054A for cushioning the interface between the PSC board 50002 and the electronics box lid 21524 (FIG. 1G) and at least one spacer 30053 for maintaining spacing between the PSC board 50002 and the PBC board 50001 (FIG. 15B). In some configurations, the spacer 30053, which may include, for example, metal, may be operably coupled to the PSC board 50002. In some configurations, the spacer 30053 can be used as an electrical connection to the MD's chassis for EMC purposes. The spacer 30053 can provide durability and robustness to the MD. The PSC board 50002 can include a charging input connector 1181, a UC connector 1179, an auxiliary connector 1175A, at least one power interconnect to a PBC connector 1173, and a canvas / PBC connector 1179A, connected as shown in FIGS. 15I and 15J. The PSC board 50002 can include at least one power switch 401C, at least one battery charging circuit 1171 / 1173A, and at least one coin cell battery 1175ABC for powering at least one real time clock 1178A (FIG. 15J). The PSC board 50002 is not limited to the components listed herein and can include any integrated circuits and other components that may enable operation of the MD.

[0147] 15I-15J, the PSC board 50002 can communicate with a battery 70001 (FIG. 15I), which can provide power to the UC 130 (FIG. 12A) and auxiliary devices, for example, but not limited to, through a 15-V regulator 1175, a UC connector 1179, a 24-V regulator 1175XYZ, and an auxiliary connector 1175A. The PSC board 50002 can communicate with a battery management system 50015 (FIG. 1E), from which, for example, but not limited to, battery capacity and temperature can be determined. The PSC board 50002 can monitor the line voltage from the battery pack 70001 (FIG. 15I), for example, whether the charger power supply cord 70002 (FIGS. 11A-11D) is plugged in. The battery 70001 (FIG. 15I) can provide power to the at least one microcontroller 401 (FIG. 15J) through, for example, but not limited to, a regulator 1176 (FIG. 15J), such as, for example, but not limited to, a 3.3-V regulator, and a regulator 1177 (FIG. 15J), such as, for example, but not limited to, a 5-V regulator. The PSC board 50002 provides power to the PBC board 50001 through a board-to-board connector 1173 / 1173A (FIG. 15J), such as, for example, but not limited to, a SAMTECPES-02. The at least one microcontroller 401 (FIG. 15J), such as, for example, but not limited to, a Renaesas RX64M, can control the opening and closing of a power switch 401C (FIG. 15J) between the battery 70001 (FIG. 15I) and the board-to-board connector 1173 / 1173A (FIG. 15J) to the PBC board 50001. At least one microcontroller 401 (FIG. 15J) can include memory 1178 (FIG. 15J), such as, but not limited to, a ferroelectric non-volatile memory that can retain data after power is turned off. The PSC board 50002 can include a real-time clock that can be used, for example, to time-stamp usage data and event logs. The real-time clock can be powered by a battery 70001 (FIG. 15I) or, alternatively, by a lithium coin cell 1175ABC (FIG. 15J).Communication between the at least one microcontroller 401 (FIG. 15J) and the battery 70001 (FIG. 15I) can be enabled by an I2C bus and an I2C accelerator 1174 (FIG. 15J). Communication between the at least one microcontroller 401 (FIG. 15J) and the UC 130 (FIG. 12A) can be enabled by the CANbus protocol through the UC connector 1179 (FIGS. 15I / 15G). Communication between the at least one microcontroller 401 (FIG. 15G) and the PBC board 50001 (FIG. 15B) can be enabled by the CANbus protocol through connector 1179A. Sensors 401B (FIG. 15J) are positioned throughout the PSC board 50002 and can determine the actual levels of voltage and current being supplied to the PBC board 50001 relative to the level of voltage reported by the battery 70001 (FIG. 15I) and sensed by sensor 410A (FIG. 15I). At least one sensor 410A (FIG. 15I) can sense high acceleration events, such as, but not limited to, hard impacts, vehicle collisions, and shipping mishandling. The high acceleration events can be logged and can be used, for example, as part of after-sales inspections and warranty claims, and can provide usage statistics that may provide data for quality improvement efforts. In some configurations, at least one sensor 410A (FIG. 15I) can reside on the PSC board 50002 and communicate, for example, via a small peripheral interface (SPI) bus to a corresponding PSC processor 401 (FIG. 15J).

[0148] Continuing with reference to FIGS. 15I-15J, power can flow from each battery pack 70001 (FIG. 15I), through the PSC board 50002, and from there through the PBC board 50001 (FIG. 15B) to the motors. The battery packs 70001 (FIG. 15I) may discharge at different rates, for example, due to internal impedance differences. Because they are electrically coupled together, the A-side batteries have approximately the same voltage and the B-side batteries have approximately the same voltage, but there may be a difference between the voltage in the A-side battery and the voltage in the B-side battery. Bus voltage can be monitored, and if necessary, the voltage of the batteries 70001 on each side can be equalized by sending a slightly larger command to the motor on the side with the higher voltage and a smaller command to the motor on the other side. Current limiting devices can be used throughout the power distribution to prevent an overcurrent condition on one subsystem from affecting power delivery to another subsystem. Anomalies caused by marginal power supply operation can be mitigated by 1) supply monitoring for critical analog circuits and 2) power supply supervisory features for digital circuits.

[0149] Referring now to FIG. 16A , the MD may include, but is not limited to, a base 21514A, a communication means 53, a powering means 54, a UC 130, and a remote control device 140. The base 21514A may communicate with the UC 130 using the communication means 53, for example, but not limited to, a protocol such as the CANVAS protocol. The user controller 130 may communicate with the remote control device 140 through, for example, but not limited to, wireless technology 18, for example, but not limited to, BLUETOOTH technology. In some configurations, the base 21514A may include redundancy, as discussed herein. In some configurations, the communication means 53 and the powering means 54 may operate within the base 21514A and may be redundant therein. In some configurations, the communication means 53 may provide communication from the base 21514A to components external to the base 21514A.

[0150] Referring now primarily to FIG. 16B , in some configurations, the MD control system 200A may include at least one infrastructure processor 100 and at least one power supply controller 11, which may communicate bidirectionally via a serial bus 143 using, but not limited to, a system serial bus messaging system 130F. The system serial bus messaging 130F may enable bidirectional communication between the external application 140, the I / O interface 130G, and the UC 130. The MD may access peripherals, processors, and controllers through interface modules, which may include, but are not limited to, an input / output (I / O) interface 130G and an external communication interface 130D. In some configurations, the I / O interface 130G may transmit / receive messages to / from, for example, but not limited to, at least one of an audio interface 150A, an electronic interface 149A, a manual interface 153A, and a visual interface 151A. Audio interface 150A can provide information to an audio device, such as a speaker, which can issue an alert, for example, when the MD requires attention. Electronic interface 149A can transmit / receive messages to / from, for example, but not limited to, external sensors 147. External sensors 147 can include, but are not limited to, time-of-flight cameras and other sensors. Manual interface 153A can transmit / receive messages to / from, for example, but not limited to, joystick 70007 (FIG. 12A) and / or switches 70036-1 / 2 (FIG. 12V) and buttons 70035 (FIG. 12H), and / or information lights such as LED lights, and / or UC 130 (FIG. 12A), which has, for example, a touchscreen. UC 130 and processor 100 can transmit / receive information to / from I / O interface 130G, external communication 130D, and each other.

[0151] Continuing to refer primarily to FIG. 16B , system serial bus interface 130F can enable communication between UC 130, processor 100 (also shown, for example, as processor A 143A ( FIG. 18C ), processor A2 43B ( FIG. 18C ), processor B1 43C ( FIG. 18D ), and processor B2 43D ( FIG. 18D )), and power controller 11 (also shown, for example, as power controller A 98 ( FIG. 18B ) and power controller B 99 ( FIG. 18B )). Messages described herein can be exchanged between UC 130 and processor 100 using, for example, but not by way of limitation, system serial bus 143. External communication interface 130D can enable communication between, for example, UC 130 and external application 140 using, for example, but not by way of limitation, wireless communication 144 such as BLUETOOTH® technology. The UC 130 and processor 100 can transmit / receive messages to / from external sensors 147 that can be used to enable automatic and / or semi-automatic control of the MD.

[0152] 17A, the platform controller 50001 (FIG. 15B) can include a platform processor 100, which can process incoming motor data 775 and sensor data 767, upon which wheel commands 769, cluster commands 771, and seat commands 773 can be based, at least in part. To perform data processing, the platform processor 100 can include, but is not limited to, a canvas controller 311 that manages communications, a motor drive control processor 305 that prepares motor commands, a timer interrupt check request processor 301 that manages timing, a vote / commit processor 329 that manages redundant data, a main loop processor 321 that manages various data inputs and outputs, and a controller processing task 325 that receives and processes incoming data. The controller processing task 325 may include, but is not limited to, an IMU filter 753 that manages IMU data preparation, a speed limit processor 755 that manages speed-related features, a weight processor 757 that manages weight-related features, an adaptive speed control processor 759 that manages obstacle avoidance, a traction control processor 762 that manages difficult terrain, and an active stabilization processor 763 that manages stability features. The inertial sensor pack 1070 / 23 / 29 / 35 may provide IMU data 767 to the IMU filter 753, which may provide data that may result in wheel commands 769 to the right wheel motor drive 19 / 31 and the left wheel motor drive 21 / 33. The IMU filter 753 may include, but is not limited to, a body velocity to gravity velocity and predicted velocity processor 1102 ( FIG. 19A ), a body velocity and gravity to Euler angles and velocity processor 1103 ( FIG. 19A ), and a gravity velocity error and predicted yaw velocity error to body velocity processor 1103 ( FIG. 19A ). The seat motors 45 / 47 may provide motor data 775 to the weight processor 757. The vote processor 329 may include, but is not limited to, a primary vote processor 873, a secondary vote processor 871, and a tertiary vote processor 875.

[0153] Referring now primarily to Figures 17B and 17C, in some configurations, the board processor 100 can share accelerometer and gyroscope data from the inertial sensor packs 1070 / 23 / 29 / 35 (Figure 17A), for example, through the canvases 53A / B (Figure 18B), as controlled by the canvas controller task 311 (Figure 17B). The board serial bus 53A / B (Figure 18B) can communicatively couple the processors A1 / A2 / B1 / B2 43A-43D (Figures 18C / 18D) and other components of the MD. The canvas controller 311 (Figure 17B) can receive interrupts when canvas messages arrive and can maintain the current frame buffer 307 (Figure 17B) and the previous frame buffer 309 (Figure 17B). When accelerometer and gyroscope data (sensor data 767 (FIG. 17A)) arrives from processors A1 / A2 / B1 / B2 43A-43D (FIGS. 18C / 18D), canvas controller 311 (FIG. 17B) can send a commit processing start message 319 (FIG. 17B) to vote / commit processor 329 (FIG. 17C). Voting / commit processor 329 (FIG. 17C) can send a commit message 331 (FIG. 17C), which may include the results of a voting process, such as, but not limited to, the voting process of method 150 (FIGS. 21B / 21C) applied to motor data 775 (FIG. 17A) and IMU data 767 (FIG. 17A), and can send a controller processing start message 333 (FIG. 17C) to controller processing task 325 (FIG. 17C). The controller processing task 325 (FIG. 17C) can calculate estimates based at least on, for example, received IMU data 767 (FIG. 17A) and motor data 775 (FIG. 17A), and can manage the traction (traction control processor 762 (FIG. 17A)), speed (speed processor 755 (FIG. 17A), adaptive speed control processor 759 (FIG. 17A)), and stabilization (active stabilization processor 763 (FIG. 17A)) of the MD based at least on the estimates, and can send motor-related messages 335.If the canvas controller 311 (FIG. 17B) does not receive a message from the processor A1 / A2 / B1 / B2 43A-D (FIG. 18C / 18D) within a timeout period, such as, but not limited to, 5 ms, the timer interrupt check request processor 301 (FIG. 17B) may start the commit backup timer 317 (FIG. 17B) which, when the timer expires, may start the commit processing by sending a commit processing start message 319 (FIG. 17B) to the commit processing task 329 (FIG. 17C). The timer interrupt check request processor 301 (FIG. 17B) can also send a main loop start message 315 (FIG. 17B) to the main loop processor 321 (FIG. 17B) when the timer expires, e.g., every 5 ms, to update the motor messages 303 (FIG. 17B) to the motor drive control 305 (FIG. 17B), and the main loop processor 321 (FIG. 17B) can capture sensor data and data from the user controller 130 (FIG. 16A). The main loop processor 321 (FIG. 17B) can send a synchronization message 313 (FIG. 17B) via the canvas 53A / B (FIG. 18B) if the main loop processor 321 (FIG. 17B) is running on the master of processors A1 / A2 / B1 / B2 43A-D (FIGS. 18C / 18D). The main loop processor 321 (FIG. 17B) can track timed activity across the infrastructure processor 21514A (FIG. 16A), can initiate other processes, and can enable communication through infrastructure output packets 323 (FIG. 17B).

[0154] 18A-18D, the PBC board 50001 (FIG. 15G) can include, but is not limited to, at least one processor 43A-43D (FIGS. 18C / 18D), at least one motor drive processor 1050, 19, 21, 25, 27, 31, 33, 37 (FIGS. 18C / 18D), and at least one power supply controller (PSC) processor 11A / B (FIG. 18B). The PBC board 50001 (FIG. 15G) can be operably coupled to, for example, but not limited to, the UC 130 (FIG. 18A) through, for example, but not limited to, electronic communication means 53C and a protocol such as the CANVAS protocol, and the PBC board 50001 (FIG. 15G) can be operably coupled to at least one IMU and inertial system processor 1070, 23, 29, 35 (FIGS. 18C / 18D). The UC 130 (FIG. 18A) can optionally be operatively coupled to electronic devices, such as, for example, but not limited to, computers, such as tablets and personal computers, phones, and light systems. The UC 130 (FIG. 18A) can include, but is not limited to, at least one joystick and at least one display. The UC 130 (FIG. 18A) can include push buttons and toggles. The UC 130 (FIG. 18A) can optionally be communicatively coupled to the peripheral control module 1144 (FIG. 18A), the sensor auxiliary module 1141 (FIG. 18A), and the autonomous control modules 1142 / 1143 (FIG. 18A). Communication can be enabled, for example, but not limited to, by the Canvas protocol and the Ethernet protocol 271 (FIG. 18A).

[0155] Continuing to refer primarily to FIGS. 18A-18D, processor 39 / 41 (FIGS. 18C / 18D) can control commands to wheel motor processors 85 / 87 / 91 / 93 (FIGS. 18C / 18D), cluster motor processor 1050 / 27 (FIGS. 18C / 18D), and seat motor processor 45 / 47 (FIGS. 18C / 18D). Processor 39 / 41 (FIGS. 18C / 18D) can receive joystick, seat height, and frame tilt commands from UC 130 (FIG. 12A). Software that may enable UC 130 (FIG. 12A) can perform user interface processing, including display processing, and can communicate with external product interfaces. Software that may enable PSC 11A / B (FIG. 18B) can read information from battery 70001 (FIG. 1E) via a bus, such as, but not limited to, an I2C bus or an SM bus, and transmit that information on canvas 53A / 53B (FIG. 18B) for interpretation by UC 130 (FIG. 12A). Boot code software running on processor 39 / 41 (FIGS. 18C / 18D) can initialize the system and provide the ability to update application software. External applications can run on processors such as, but not limited to, personal computers, mobile phones, and mainframe computers. External applications can communicate with the MD, for example, to support configuration and development. For example, a product interface is an external application that can be used, for example, by maintenance personnel, manufacturers, and clinicians to configure and service the MD. The engineering interface is an external application that can be used, for example, by a manufacturer, to communicate with UC 130 (FIG. 12A), processor 39 / 41 (FIGS. 18C / 18D), and PSC 11A / B (FIG. 18B) when operating the MD. The software installer is an external application that can be used, for example, by a manufacturer and maintenance personnel, to install software on UC 130 (FIG. 12A), processor 39 / 41 (FIGS. 18C / 18D), and PSC 11A / B (FIG. 18B).

[0156] Continuing to refer primarily to Figures 18C-18D, in some configurations, each at least one processor 43A-43D (Figures 18C / 18D) may include, but is not limited to, at least one cluster motor drive processor 1050, 27 (Figures 18C / 18D), at least one right wheel motor drive processor 19, 31 (Figure 18C), at least one left wheel motor drive processor 21, 33 (Figures 18C / 18D), at least one seat motor drive processor 25, 37 (Figures 18C / 18D), and at least one inertial sensor pack processor 1070, 23, 29, 35 (Figures 18C / 18D). At least one processor 43A-43D further includes at least one cluster brake processor 57 / 69 (FIGS. 18C / 18D), at least one cluster motor processor 83 / 89 (FIGS. 18C / 18D), at least one right wheel brake processor 59 / 73 (FIGS. 18C / 18D), at least one left wheel brake processor 63 / 77 (FIGS. 18C / 18D), and at least one right wheel motor processor 85 / 91 (FIGS. 18C / 18D). The system may include at least one left wheel motor processor 87 / 93 (FIGS. 18C / 18D), at least one seat motor processor 45 / 47 (FIGS. 18C / 18D), at least one seat brake processor 65 / 79 (FIGS. 18C / 18D), at least one cluster position sensor processor 55 / 71 (FIGS. 18C / 18D), and at least one manual brake release processor 61 / 75 (FIGS. 18C / 18D). The processors 43A-43D may be used to drive a cluster assembly 21100 (FIG. 6A) of wheel-forming ground-contacting modules. The ground-contacting modules may be mounted on the cluster assembly 21100 (FIG. 6A), and each wheel of the ground-contacting module may be driven by a wheel motor drive commanded by a right wheel motor drive processor A19 (FIG. 18C) or a redundant right wheel motor drive processor B31 (FIG. 18D). The cluster assembly 21100 (FIG. 6A) can rotate about a cluster axis, with the rotation being governed, for example, by the cluster motor drive processor A1050 (FIG. 18C) or the redundant cluster motor drive processor B27 (FIG. 18D).For example, at least one of the sensor processors, such as, but not limited to, at least one cluster position sensor processor 55 / 71 (FIGS. 18C / 18D), at least one manual brake release sensor processor 61 / 75 (FIGS. 18C / 18D), at least one motor current sensor processor (not shown), and at least one inertial sensor pack processor 17, 23, 29, 35 (FIGS. 18C / 18D), can process data transmitted from sensors resident on the MD. Processors 43A-43D (FIGS. 18C / 18D) can be operably coupled to UC 130 (FIG. 18A) to receive user input. Communications 53A-53C (FIG. 18B) between UC 130 (FIG. 18A), PSCs 11A / 11B (FIG. 18B), and processors 43A-43D (FIGS. 18C / 18D) can follow any protocol, including, but not limited to, the CANVAS protocol. At least one VBus 95 / 97 (FIG. 18B) can operably couple at least one PSC 11A / B (FIG. 18B) to processors 43A-43D (FIGS. 18C / 18D) and, through an external VBus 107 (FIG. 18B), to components external to the PBC board 50001 (FIG. 15G). In some configurations, processor A 143A (FIG. 18C) can be the master of canvas A 53A (FIG. 18B). Slaves on canvas A 53A (FIG. 18B) can be processor A 243B (FIG. 18C), processor B 143C (FIG. 18D), and processor B 243D (FIG. 18D). In some configurations, processor B 143C (FIG. 18D) can be the master of canvas B 53B (FIG. 18B). The slaves on canvas B 53B (FIG. 18B) can be processor B 2 43C (FIG. 18D), processor A 1 43A (FIG. 18C), and processor A 2 43B (FIG. 18C). In some configurations, UC 130 (FIG. 18A) can be the master of canvas C 53C (FIG. 18B). The slaves on canvas C 53C (FIG. 18B) can be PSC 11A / B (FIG. 18B) and processors A1 / A2 / B1 / B2 43A / B / C / D (FIGS. 18C / 18D).A master node (either processors 43A-43D (FIGS. 18C / 18D) or UC 130 (FIG. 18A)) can send data to or request data from a slave.

[0157] Referring primarily to FIGS. 18C / 18D, in some configurations, the base controller board 50001 (FIG. 15G) can include a redundant processor set A / B 39 / 41, which controls the cluster 21100 (FIG. 6A) and can rotate the drive wheels 21201 (FIG. 7B). The right / left wheel motor drive processors A / B 19 / 21, 31 / 33 can drive the right / left wheel motors A / B 85 / 87 / 91 / 93, which drive the right and left wheels 21201 (FIG. 7B) of the MD. The wheels 21201 (FIG. 7B) can be coupled and driven together. Turning can be accomplished by driving the left wheel motor processor A / B 87 / 93 and the right wheel motor processor A / B 85 / 91 at different speeds. The cluster motor drive processor A / B1050 / 27 can drive the cluster motor processor A / B83 / 89, which can rotate the wheel base in a forward / rearward direction, which can allow the MD to remain level while the front wheels 21201 (FIG. 6A) are higher or lower than the rear wheels 21201 (FIG. 6A). The cluster motor processor A / B83 / 89 can keep the MD level when going up and down curbs, and can repeatedly rotate the wheel base to go up and down stairs. The seat motor drive processor A / B25 / 37 can drive the seat motor processor A / B45 / 47, which can raise and lower the seat (not shown).

[0158] Continuing with reference to FIGS. 18C / 18D, cluster position sensor processor A / B 55 / 71 can receive data from the cluster position sensor, which may indicate the position of cluster 21100 (FIG. 3). Data from the cluster position sensor and seat position sensor can be communicated between processors 43A-43D and used by processor set A / B 39 / 41 to determine information to be sent, for example, to right wheel motor drive processor A / B 19 / 31, cluster motor drive processor A / B 15 / 27, and seat motor drive processor A / B 25 / 37. Independent control of cluster 21100 (FIG. 3) and drive wheel 21201 (FIG. 7B) can enable the MD to operate in several modes, thereby allowing a user or processors 43A-43D to switch between modes, for example, in response to local terrain.

[0159] Continuing with reference to FIGS. 18C / 18D, the inertial sensor pack processors 1070, 23, 29, 35 can receive data that may indicate, for example, but not by way of limitation, the orientation of the MD. Each inertial sensor pack processor 1070, 23, 29, 35 can process data from, for example, but not by way of limitation, accelerometers and gyroscopes. In some configurations, each inertial sensor pack processor 1070, 23, 29, 35 can process information from four sets of three-axis accelerometers and three-axis gyroscopes. The accelerometer and gyroscope data can be fused to produce a gravity vector that can be used to calculate the orientation and inertial rotation rate of the MD. The fused data can be shared across processors 43A-43D and can be subject to threshold criteria. The threshold criteria can be used to improve the accuracy of the device orientation and inertial rotation rate. For example, fused data from one processor 43A-43D that exceeds a certain threshold can be discarded. The fused data from each of the processors 43A-43D within preselected limits can be averaged or processed in any other manner, for example, without limitation. The inertial sensor pack processors 1070, 23, 29, 35 can process data from sensors such as, for example, an STmicroelectronics LSM330DLC, or any sensor providing a 3D digital accelerometer and a 3D digital gyroscope, or any sensor capable of measuring gravity and body velocity. The sensor data can undergo processing, for example, without limitation, filtering, to improve control of the MD. The cluster position sensor processors A / B55 / 71, seat position sensor processors A / B67 / 81, and manual brake release sensor processors A / B61 / 75 can process, without limitation, Hall sensor data. Processors 39 / 41 can manage the storage of user-specific information.

[0160] Referring now primarily to FIG. 19A , at least one inertial sensor pack processor 17, 23, 29, 35 (FIG. 18C / 18D) can process sensor information from the IMU 608 (FIG. 15D) through an IMU filter 9753. A state estimator can estimate the dynamic state of the MD with respect to an inertial frame of reference from sensor information measured in the body frame, i.e., with respect to a frame associated with the MD. The estimation process can include relating the inertial frame of reference to acceleration and velocity measurements made by the IMU board 50003 (FIG. 15B) on an onboard axis system (body frame) to generate a dynamic state estimate. The dynamic state relating the body and inertial frames of reference can be described using Euler angles and velocities, which are calculated from an estimate of the Earth's gravitational field vector. A gyroscope can provide velocity measurements relative to its onboard frame of reference. Pitch Euler angles 9147 and roll Euler angles 9149 can be estimated as follows:

[0161] Mapping velocities from the body coordinate frame of reference to the inertial coordinate frame of reference can include evaluating kinematic equations of rotation of vectors. [ka] During the ceremony, [ka] is the gravity velocity vector, [ka] is the filtered gravity vector, and Ω f is the body velocity vector.

[0162] Integrating over time, we get [ka] provides the gravity vector estimate. The predicted gravity velocity estimate is: [ka] During the ceremony, [ka] is the predicted velocity of gravity.

[0163] Inverse mapping of the inertial rates to the body coordinate frame to integrate the error and compensate for the gyroscope bias can be accomplished as follows: [ka] During the ceremony, [ka] is the gravitational velocity error, Ω e is the body velocity error, which is equivalent to: [ka] During the ceremony, [ka] are the components of the filtered gravity vector 9125, [ka] is the component of the filtered body velocity error 9157, [ka] are the components of the filtered gravity velocity error 9129. The predicted gravity velocity can be calculated as follows: [ka] or [ka] Combined with the above matrix, this results in a matrix that can be viewed in the form Ax=b. [ka] To solve for the body velocity error 9157, the pseudo-inverse of the "A" matrix can be calculated as follows: [ka] The transpose 'A' matrix multiplied by the 'A' matrix results in the following matrix: [ka]

[0164] Since the filtered gravity vector 9125 is a unit vector, the above matrix simplifies to a 3x3 identity matrix, whose inverse is also a 3x3 identity matrix. Thus, the pseudo-inverse solution to the Ax=b problem is summarized below: [ka] During the ceremony, [ka] is the difference between the predicted gravity velocity 9119 and the wheel velocity derived from the data received from the right / left wheel motors. The resulting matrix can be written as the following identity: [ka] The filtered gravity vector 9125 can be converted to an Euler pitch 9147 and an Euler roll 9149 . Euler angles: θ(pitch)=-asin(G fy ) φ(roll)=-atan(G fx / G fz ) The filtered body velocity can be converted to an Euler pitch velocity 9153 and an Euler roll velocity 9155. Pitch Speed: [ka] Roll Speed: [ka] Yaw speed: [ka]

[0165] Continuing with reference to FIG. 19A , IMU filter 9753 can filter gravity vector 9125, which can represent the inertial z-axis. IMU filter 9753 can provide a two-dimensional inertial reference in three-dimensional space. Measured body velocity 9113 (e.g., measured from a gyroscope, which can be part of the inertial sensor pack), filtered gravity vector 9127 calculated based on accelerometer data, and differential wheel velocity 9139 (which can be calculated from data received from the right / left wheel motor drives of left and right wheels 21201 ( FIG. 1A )) can be input to IMU filter 9753. IMU filter 9753 can calculate pitch 9147, roll 9149, yaw rate 9151, pitch rate 9153, and roll rate 9155, which are used, for example, to calculate wheel command 769 ( FIG. 21A ). The filtered output (G ) and measured input (G ) can be used to calculate the wheel command 769 ( FIG. 21A ). meas ) along with a comparison of the gravity predicted velocity and the differential wheel velocity are compared to determine an error. The error is fed back into the velocity measurements to compensate for velocity sensor bias. The filtered gravity vector 9125 and filtered body velocity 9115 can be used to calculate pitch 9147, roll 9149, yaw rate 9151, pitch rate 9153, and roll rate 9155.

[0166] 19B , a method 9250 for processing data using an IMU filter 9753 ( FIG. 19A ) may include, without limitation, subtracting 9251 gyroscope bias from gyroscope readings to remove offsets. Method 9250 may further include calculating 9255 a gravity velocity vector 9143 ( FIG. 19A ) and a predicted gravity velocity estimate 9119 ( FIG. 19A ) based on at least a filtered body velocity 9115 ( FIG. 19A ) and a filtered gravity vector 9125 ( FIG. 19A ). Method 9250 may still further include subtracting 9257 a product of gain K1 and gravity vector error from gravity velocity vector 9117 ( FIG. 19A ) and integrating 9259 filtered gravity velocity 9143 ( FIG. 19A ) over time to determine a filtered gravity vector 9125 ( FIG. 19A ). The gravity vector error 9129 ( FIG. 19A ) can be based on at least the filtered gravity vector 9125 ( FIG. 19A ) and the measured gravity vector 9127 ( FIG. 19A ). The method 9250 can further include calculating 9261 a pitch rate 9153 ( FIG. 19A ), a roll rate 9155 ( FIG. 19A ), a yaw rate 9151 ( FIG. 19A ), pitch, and roll based on the filtered gravity velocity vector 9125 ( FIG. 19A ) and the filtered body velocity 9115 ( FIG. 19A ). The gyroscope bias 9141 ( FIG. 19A ) can be calculated by subtracting the differential wheel velocity 9139 ( FIG. 19A ) between the wheels 21201 ( FIG. 1A ) from the predicted gravity velocity estimate 9119 ( FIG. 19A ) to determine a predicted velocity error 9137 ( FIG. 19A ). Additionally, the cross product of the gravity vector error 9129 (FIG. 19A) and the filtered gravity vector 9125 (FIG. 19A) can be calculated and added to the dot product of the filtered gravity vector 9125 (FIG. 19A) and the predicted gravity velocity estimate error 9137 (FIG. 19A) to determine the body velocity error 9157 (FIG. 19A).Method 9250 can include calculating gyroscope bias 9141 (FIG. 19A) based on applying gain K2 9133 (FIG. 19A) to the integral over time 9135 (FIG. 19A) of body rate error 9157 (FIG. 19A) to determine the gyroscope bias that is subtracted in step 9251. The equation describing method 9250 is: [ka] During the ceremony [ka] is the measured gravity velocity vector, [ka] is the filtered gravity vector and ω is the filtered body velocity vector. [ka] During the ceremony, [ka] is the predicted speed. [ka] During the ceremony, [ka] is the predicted velocity error, [ka] is the differential wheel speed. [ka] During the ceremony, [ka] is the filtered gravity velocity, [ka] is the measured gravity velocity vector, K1 is the gain, [ka] is the gravity error vector. [ka] In the formula, G m is the gravity vector measured from the accelerometer readings. [ka] During the ceremony, [ka] is the body velocity error vector, [ka] is the gravity velocity error vector. [ka] During the ceremony, [ka] is the integrated body velocity error vector and K29133 (FIG. 19A) is the gain. [ka] In the formula, ω m is the measured body velocity vector. [ka]

[0167] 20, field weakening allows the motor to run temporarily at a higher speed whenever necessary, for example, when an unexpected situation arises. The electrical system equations of motion for the motor in the rotating reference frame are: [ka] [ka] In the formula, V dLN is the DC voltage line to the neutral point, ω e is the electrical speed, L LN is the winding inductance line to the neutral, I q are the quadrature currents, I d is a direct current, R LN is the neutral grounding resistance, V qLN are the quadrature voltage lines to the neutral point, K eLN is the back EMF line to the neutral point, ω m is the mechanical speed, Under normal magnetic field direction control of the brushless motor drive unit, I d is adjusted to zero, resulting in: [ka] [ka] To implement field weakening in a field-oriented control scheme, the term ω e L LN I q can be increased by providing a non-zero current command to the DC current controller, resulting in higher motor speed and reduced torque capability.

[0168] Continuing to refer to Figure 20, field weakening in the rotating frame of reference can be implemented as follows: In a conventional drive without field weakening, the maximum command voltage is: [ka] wherein V bus is the bus voltage. As the quadrature command voltage increases, the motor drive voltage controller increases the duty cycle to match the commanded input until it reaches its maximum back EMF voltage, where the duty cycle is equal to the command voltage. When the DC current is regulated to zero, under normal motor control conditions without field weakening, [ka] In the formula, V command is the voltage commanded from the board. Under field-weakening conditions, the last term in equation (2) is non-zero, resulting in: [ka] When the quadrature voltage saturates at the bus, the direct axis current can be commanded to a non-zero value, increasing the motor speed and emulating a higher voltage command to the motor as imposed by the base wheel speed controller. By isolating the DC current component of equation (6), the DC current command can be calculated as follows: [ka] The speed controller can effectively command a higher speed to the motor, and the motor can behave as if it were receiving a higher voltage.

[0169] 20, in some configurations, adding about 25 amps of DC current can approximately double the maximum speed of some motors, allowing for relatively short bursts of higher speeds when, for example, unexpected regulation is required. The current and voltage command limits can be calculated as follows: [ka] [ka] The DC current controller has priority when regulating the DC current, leaving the remainder to the quadrature controller, which can report subsequent limits to processor A / B 39 / 41 (FIGS. 18C / 18D).

[0170] Continuing with reference to FIG. 20, a method 10160 for calculating command voltage and current limits may include, but is not limited to, calculating an overall current limit I based on FET temperature. lim and calculating 10161 the measured bus voltage, [ka] Based on the voltage limit V lim Method 10160 can include setting 10163 the quad voltage controller current limit based on the overall current limit and the commanded DC current from a previous measurement. Method 10160 can further include calculating 10165 the DC current command and calculating 10166 the overall current limit I lim and the commanded DC voltage V dLNCommanded The method 10160 can include setting 10167 a quad voltage controller current limit based on the overall voltage limit and the commanded DC voltage from the DC current controller.

[0171] Continuing with reference to FIG. 20, in a conventional motor drive, voltage saturation occurs when the voltage command from the current controller exceeds the bus voltage limit. [ka] When field weakening is used, the motor drive injects DC current to increase motor speed when the quadrature voltage saturates. The DC current controller calculates the DC current command only when the commanded voltage exceeds the bus's ability to command the quadrature voltage. Otherwise, the DC current is adjusted to zero to maintain efficiency. Thus, voltage saturation can be reported when the DC current controller attempts to adjust the DC current command to its maximum value, rather than when the quadrature voltage saturates at the bus voltage limit, as in conventional drives. In conventional motor drives, current saturation is reported when the current command from the voltage controller saturates at a maximum current, for example, but not limited to, 35 amps, unless otherwise limited by heat. However, the voltage controller's current command saturates when the maximum quadrature voltage command reaches the bus limit. If this were true for field weakening, the voltage controller would report current saturation regardless of the actual quadrature current. Thus, if the quadrature voltage controller is issuing a maximum current command and the quadrature current controller has not run out of voltage headroom, then the maximum current is reached. If the quadrature current controller has run out of voltage headroom, then the quadrature current controller is unable to produce the maximum current and the current limit has not been reached.

[0172] Referring now primarily to FIG. 21A , to enable fail-safe operation, the MD can include, but is not limited to, redundant subsystems, whereby failures can be detected, for example, by comparing data associated with each subsystem with data associated with the remaining subsystems. Fault detection within redundant subsystems can create fault-tolerant functionality, and the MD can continue operation based on information provided by the remaining non-faulty subsystems if one subsystem is found to be faulty until the MD can be brought into a safe mode without endangering the user. If a failed subsystem is detected, the remaining subsystems can be required to agree within predefined limits to continue operation, and operation can be terminated in the event of a mismatch between the remaining subsystems. The voting processor 329 can include, but is not limited to, at least one method for determining values ​​to use from redundant subsystems, and in some configurations, the voting processor 329 can manage different types of data, for example, but not limited to, calculated command data and inertial measurement unit data, in different ways.

[0173] 21A , the voting processors 329 may include, but are not limited to, a primary voting processor 873, a secondary voting processor 871, and a tertiary voting processor 875. The primary voting processor 873 may include, but is not limited to, computer instructions for averaging the sensor data 767 or command data 767A (referred to herein as processor values) from each processor A1 / A2 / B1 / B2 43A-43D (FIGS. 18C / 18D). The primary voting processor 873 may further include computer instructions for calculating the absolute difference between each processor value and the average value, discarding the highest absolute difference, and retaining the three remaining processor values. The secondary voting processor 871 may include, without limitation, computer instructions for calculating differences between the remaining processor values ​​and each other, comparing the differences to a preselected threshold, comparing the remaining values ​​to the processor value with the highest difference therebetween, voting out the processor value with the highest difference from the remaining values, comparing the voted-out value to the remaining values, voting out any differences above the preselected threshold, if applicable, and selecting either the remaining processor value or an average of the processor values, e.g., depending on the type of data the processor values ​​represent. The tertiary voting processor 875 may include, without limitation, computer instructions for comparing the discarded value to the remaining values ​​if no differences above the preselected threshold exist, voting out the discarded value if any differences above the preselected threshold exist, and selecting either one of the remaining processor values ​​or an average of the remaining processor values, e.g., depending on the type of data the processor values ​​represent. The tertiary voting processor 875 may also include computer instructions for selecting either the remaining processor value or an average of the remaining processor values ​​if no differences above the preselected threshold exist. It is also possible that no discarded values ​​are voted out, and all processor values ​​remain selected or averaged.The tertiary voting processor 875 may still further include computer instructions for issuing an alarm if a processor value is voted out a preselected number of times, and for incrementing a frame counter if the voting scheme fails to find a processor value that meets the selection criteria. The tertiary voting processor 875 may also include computer instructions for discarding frames containing processor values ​​for which the voting scheme failed to find a processor value that meets the selection criteria if the frame counter does not exceed a preselected number of frames, and for selecting a last frame with at least one processor value that may be used. The tertiary voting processor 875 may also include computer instructions for transitioning the MD into a fail-safe mode if the frame counter exceeds a preselected number of frames.

[0174] 21B and 21C, a method 150 for resolving a value to use from redundant processors, referred to herein as "voting," may include, but is not limited to, initializing a counter 149, averaging 151 values, such as, but not limited to, sensor or command values ​​(referred to herein as processor values), from each processor 43A-43D (FIG. 21A), calculating 153 the absolute difference between each processor value and the average value, and discarding the highest difference. Method 150 may further include calculating 155 the differences between the remaining processor values ​​and each other. If there are any differences above a preselected threshold at 157, method 150 may include comparing 167 the remaining values ​​with the value having the highest difference therebetween, voting 169 the value with the highest difference out of the remaining values, comparing 171 the voted-out value with the remaining values, and voting 173 out any differences above the preselected threshold and selecting one of the remaining processor values ​​or an average of the processor values. For example, if processor values ​​from processors A1 43A (FIG. 21A), B1 43C (FIG. 21A), and B2 43D (FIG. 21A) remain, a processor value (or an average of the processor values) from any of the remaining processors may be selected. If there are no differences above a preselected threshold at 157, method 150 may compare 159 the voted-out value with the remaining values. If there are any differences above a preselected threshold at 161, method 150 may include voting out 163 the values ​​voted out in comparing 159 and selecting one of the remaining processor values ​​or an average of the remaining processor values. If there are no differences above a preselected threshold at 161, method 150 may include selecting 165 one of the remaining processor values ​​or an average of the remaining processor values. If the processor value is voted out a preselected number of times at 185, method 150 may include issuing an alarm 187.If the voting scheme fails to find a processor value that meets the selection criteria at 175, method 150 may include incrementing 177 a counter. If the counter does not exceed a preselected number at 179, method 150 may include discarding frames that have no remaining processor values ​​and selecting 181 a previous frame that has at least one processor value that meets the selection criteria. If the frame counter exceeds a preselected number at 179, method 150 may include transitioning 183 the MD into a fail-safe mode.

[0175] Referring now primarily to FIG. 21D, voting example 1519 can include a first calculation 521, in which the processor values ​​for processors A1-B2 43A-43D (FIG. 21A) can be averaged and compared to the calculated average value. The processor with the greatest difference from the average value, in example 1 519, processor A1 43A (FIG. 21A), can be discarded. The processor value from processor B2 43D (FIG. 21A) can be discarded instead. A second calculation 523 can include a comparison between the processor values ​​of the remaining three processors A2 / B1 / B2 43B-43D (FIG. 21A). The comparison can be made between the discarded processor value of processor A1 43A (FIG. 21A) and the processor values ​​of the three remaining processors A2 / B1 / B2 43B-43D (FIG. 21A). In example 1 519, none of the differences exceed an example threshold of 15. The voting result from Example 1 519 is that any of the processor values ​​from processors A1 / A2 / B1 / B2 43A-43D (FIG. 21A) can be selected.

[0176] Referring now primarily to FIG. 21E, voting example 2 501 can include a first calculation 507, in which the processor values ​​for processors A1-B2 43A-43D (FIG. 21A) can be averaged and compared to the calculated average value. The processor with the greatest difference from the average value, in example 2 501, processor A1 43A (FIG. 21A), is discarded. A second calculation 509 can include a comparison between the processor values ​​of the remaining three processors A2 / B1 / B2 43B-43D (FIG. 21A). In example 2 501, none of the differences exceed an example threshold of 15. A comparison can be made between the processor value of the discarded processor A1 43A (FIG. 21A) and the three processor values ​​of the remaining processors A2 / B1 / B2 43B-43D (FIG. 21A). In Example 2 501, one of the differences is processor A1 43A (FIG. 21A) and processor B2 The difference between the processor values ​​of processors A2 / B1 / B2 and A3 / B3 / B4 (FIG. 21A) exceeds an exemplary threshold of 15. Because one difference exceeds the exemplary threshold, the processor value from discarded processor A1 43A (FIG. 21A) can be voted out. The voting results from Example 2 501 show that processor A1 43A (FIG. 21A) was voted out, and so processors A2 / B1 / B2 Any of the processor values ​​from 43A-43D (FIG. 21A) can be selected.

[0177] Referring now primarily to FIG. 21F, voting example 3 503 can include a first calculation 511, in which the processor values ​​for processors A1-B2 43A-43D (FIG. 21A) can be averaged and compared to the calculated average value. The processor with the greatest difference from the average value, in example 3 503, processor A1 43A (FIG. 21A), is discarded. A second calculation 513 can include a comparison between the processor values ​​of the remaining three processors A2 / B1 / B2 43B-43D (FIG. 21A). In example 3 511, none of the differences exceed an example threshold of 15. A comparison can be made between the processor value of the discarded processor A1 43A (FIG. 21A) and the processor values ​​of the three remaining processors A2 / B1 / B2 43B-43D (FIG. 21A). In Example 3 511, two of the differences, the difference between processor A1 43A (FIG. 21A) and processors B1 / B2 43C / 43D (FIG. 21A), exceed the exemplary threshold of 15. Because at least one difference exceeds the exemplary threshold, the processor value from discarded processor A1 43A (FIG. 21A) can be voted out.

[0178] where Mainly Figure 21G SeeIn accordance with example 4 of the voting process 505, a first calculation 515 can be performed in which the processor values ​​for processors A1-B2 43A-43D (FIG. 21A) can be averaged and compared to the calculated average value. The processor with the greatest difference from the average value, in example 4 515, processor B2 43D (FIG. 21A), is discarded. A second calculation 517 can include a comparison between the processor values ​​of the remaining three processors A1 / A2 / B1 43A-43C (FIG. 21A). In example 4 505, the difference between the processor values ​​of processors A1 / B1 43A / C (FIG. 21A) exceeds an exemplary threshold of 15. A comparison can be performed between the processor value of processor A1 / B1 43A / C (FIG. 21A) and the remaining processor A2 43B (FIG. 21A). In Example 4 505, the difference between the processor values ​​of processors A1 / A2 43A / B (FIG. 21A) is equal to threshold 15, and therefore, of the two processors A1 / B1 43A / C (FIG. 21A), processor A1 43A (FIG. 21A) can be discarded. A comparison can be made between the processor value of the discarded processor A1 / B2 43A / 43D (FIG. 21A) and the processor values ​​of the two remaining processors A2 / B1 43B-43C (FIG. 21A). In Example 4 505, one of the differences, processor A1 The difference between the processor values ​​of processor A1 43A (FIG. 21A) and processor A2 43B (FIG. 21A) does not exceed the exemplary threshold of 15. Therefore, the processor values ​​from processors A1 and B2 43A / D (FIG. 21A) can be voted out. The voting result from Example 4 505 is that a processor value from either processor A2 43B (FIG. 21A) or B1 43C (FIG. 21A) can be selected, with A2 43B (FIG. 21A) being selected in Example 4 505.

[0179] Referring now to FIG. 22A , the MD can operate in several modes. In standard mode 100-1, the MD can operate on two drive wheels and two caster wheels. Standard mode 100-1 can provide turning capability and mobility on relatively firm, level surfaces (e.g., indoor environments, sidewalks, paved roads). Seat tilt can be adjusted to provide pressure relief, tilting both the seat bottom and back. From standard mode 100-1, a user can transition to balance mode 100-3 through four-wheel 100-2, docking 100-5, stair 100-4, and remote 100-6 modes, and other modes. Standard mode 100-1 can be used where surfaces are smooth and ease of turning is important, for example, but not limited to, positioning the chair against a desk, maneuvering for transporting the user to and from other supports, and riding around the office or home. Transitioning to standard 100-1, remote 100-6, and docked mode 100-5 can be based on the operating mode and cluster / wheel speed the MD is currently in. In extended or four-wheel mode 100-2, the MD can operate on four drive wheels, be actively stabilized through onboard sensors, and elevate the main chassis, casters, and seating arrangement. Four-wheel mode 100-2 can provide users with mobility in a variety of environments, allowing them to climb steep inclines and navigate soft and uneven terrain. In four-wheel mode 100-2, all four drive wheels can be deployed and the caster wheels can be retracted by rotating the MD. Driving all four wheels and equalizing the weight distribution over the wheels can allow the MD to ascend and descend steep slopes and drive through many types of gravel, sand, snow, and mud. Cluster rotation allows operation over uneven terrain and can maintain the device's center of gravity over the wheels. The drive wheels can climb and climb over curbs. This functionality provides users with mobility in a variety of outdoor environments. The seat height can be adjusted by the user to overcome obstacles and provide the necessary clearance along slopes.Users can be directly trained to operate in four-wheel mode for up to 10° of vertical tilt, and stability can be tested and demonstrated up to 12°. The MD is firm and stable, yet can also operate on wet outdoor surfaces.

[0180] Continuing with reference to FIG. 22A , frost heave and other natural phenomena can degrade outdoor surfaces, creating cracks and loose material. In four-wheel mode 100-2, the MD can operate on these degraded surfaces under preselected conditions. Four-wheel mode 100-2 can be available for user selection from, for example, standard 100-1, balance 100-3, and staircase 100-4 modes. The user may transition from four-wheel mode 100-2 to each of these other modes. In the event of loss of stability in balance mode 100-3 due to loss of traction or driving into an obstacle, the MD can attempt to perform an automatic transition to four-wheel mode 100-2. Sensor data and user commands can be processed in a closed-loop control system, allowing the MD to react to changes in pitch caused by terrain changes, external influences, and other factors. Four-wheel mode 100-2 can maintain stability using both the wheels and cluster motors. Obstacle traversal can be a dynamic activity, with the user and MD potentially pitching back and forth as the wheels follow the terrain and the cluster motors compensate for the changing slope of the terrain. Four-wheel mode 100-2 can protect the user, if necessary, by coordinating the wheels and cluster motors to keep the MD directly beneath the user. Four-wheel mode 100-2 can give the user the ability to traverse uneven terrain, such as slopes, gravel, and curbs. Four-wheel mode 100-2 can be used to provide automatic transition from balance mode 100-3 if two wheel controllers fail (due to loss of traction, collision, etc.) and normal transition to the top from stair mode 100-4. The seat height can be adjustable between a "cluster gap height" and a maximum seat height. The frame tilt position can be set to an optimal position for active stabilization. Four-wheel mode 100-2 can coordinate the wheels and cluster servos to actively stabilize the MD.

[0181] Continuing with reference to FIG. 22A , in balance mode 100-3, the MD can operate on two drive wheels at an elevated seat height and can be actively stabilized through onboard sensors. Balance mode 100-3 can provide mobility at an elevated seat height. In balance mode 100-3, the MD can mimic human balance, i.e., the MD can operate on two wheels. The additional height is achieved, in part, by rotating the cluster and placing a single pair of wheels directly under the user. Seat height may also be adjusted by the user. Balance mode 100-3 can be requested from several modes and can be entered when the wheels and cluster motors are substantially stationary and the MD is level. Calibration mode can be used to determine the user's center of gravity for a specific MD. In calibration mode, the user can achieve balance at a defined calibration point while the controller averages the MD's pitch. The averaged values ​​can be stored along with the seat height and cluster position for use in calculating a user center of gravity (CG) fit parameter. The CG fit parameter can be used to determine the MD / user's center of gravity. In stair mode 100-4, the MD can ascend and descend stairs using the wheel cluster and can be actively stabilized. The MD can ascend and descend stairs by rotating the cluster while the machine is balanced, at least in part, by the user or attendant. The user can control the movement of the cluster by offsetting the MD from the balance point. If the MD is pitched forward, the cluster can rotate in a downward ascending / descending direction (the stairs can be ascended and descended with the user facing away from the stairs). Conversely, if the MD is pitched backward, the cluster can rotate in an upward ascending / descending direction. The user can balance the MD by applying a moderate force to the handrails, or alternatively, a helper can balance the MD using an attendant handle on the MD. Stair mode 100-4 can enable the user to ascend and descend stairs.If the MD begins to lose stability in stair mode 100-4, instead of tipping forward, the MD may be tipped backwards, providing a safety feature for the user.

[0182] Continuing with reference to FIG. 22A , in remote mode 100-6, the MD can operate on four drive wheels without being ridden. Remote mode 100-6 can provide a user with a way to operate the device when not seated in it. This mode can be useful for transporting, parking the device after transport (e.g., after transporting to a bed, the user can move the device out of the way), and maneuvering the device for other purposes. Remote mode 100-6 can be used in any environment where standard mode 100-1 can be used, as well as on steep slopes. In remote mode 100-6, the MD can operate on four drive wheels on the ground with the frame tilt reclined so that the casters can be elevated. The joystick 70007 ( FIG. 12A ) can be inactive unless the frame tilt is at the rear detent. The rear detent can be selected to provide sufficient caster clearance for climbing a relatively steep incline forward, such as a 20° incline. The UC 130 (FIG. 12A) can remotely communicate with the device, for example, through a wireless interface, which can control the MD in remote mode 100-6. In optional docking mode 100-5, the MD operates on four drive wheels and two caster wheels, thus allowing the main chassis to be lowered. Docking mode 100-5 can allow a user to maneuver the MD for engagement with a docking base. Docking mode 100-5 can operate in a configuration that can lower the docking attachment and engage the MD with a vehicle docking base. Docking mode 100-5 can be used, for example, in an automotive vehicle configured with a docking base. Utility mode can be used to access various device features, configure the MD, or diagnose problems with the MD. Utility mode can be activated when the device is stationary and in standard mode 100-1.

[0183] Continuing with reference to FIG. 22A , the MD can enter standard mode 100-1 when the caster wheels 21001 ( FIG. 7 ) are deployed, when the frame tilt is reclined and on four drive wheels 21201 ( FIG. 1A ), or when the seat is adjusted during transition. In standard mode 100-1, the MD can use inertial data to set tilt limits, seat height limits, speed, and acceleration to improve the stability of the MD. If inertial data is unavailable, the speed, acceleration, seat height, and tilt limits can assume default values, which may be, but are not limited to, conservative estimates. In standard mode 100-1, active control may not be required to maintain the MD in an upright position. The MD can continue in standard mode 100-1 after a failure of one of the redundant systems. In some configurations, entry into standard mode 100-1 can depend on the MD's current mode. In some configurations, entry into standard mode 100-1 can depend on at least cluster and wheel speed. When the MD is in remote mode 100-6, transition to standard mode 100-1 can be based on the MD's movement and the position of the caster wheels 21001 (FIG. 7). In some configurations, transition to standard mode 100-1 can be based on the MD's movement. In some configurations, transition to standard mode 100-1 can activate a seat controller, which can place the MD in a submode based on the MD's current mode. The MD's tilt and seat limits, joystick status, and cluster velocity can be based on the submode. While in standard mode 100-1, the MD can receive and filter desired forward / aft and yaw rates, calculate cluster velocity, wheel and yaw position, and velocity error, and limit speed if required. While in standard mode 100-1, the MD can apply wheel and cluster brakes when the MD is not moving, for example, to conserve power, monitor wheel speed, and disable the joystick 70007 (FIG. 12A).In some configurations, if the data coming from the IMU 50003 (FIG. 15C) is inaccurate, the MD can automatically adjust back the tilt limit and acceleration. In some configurations, if the joystick command is in the opposite direction of the current speed, the brakes can be adjusted to minimize any sudden changes from reverse to forward commands that can occur on an uphill slope and cause stability problems.

[0184] 22A, in some configurations, in standard mode 100-1, there can be multiple machine states, such as, but not limited to, drive, recline, and transition. In drive state, caster wheels 21001 (FIG. 7) can touch the ground, and the front drive wheels 21203 (Fig. 1A)can be held off the ground. In the reclined state, the caster wheels 21001 (FIG. 7) can be raised off the ground, the cluster can be moved by the user, and the joystick can be disabled. In the transition state, ...

Claims

1. 1. A method for controlling a mobility assistance device, the method comprising: receiving terrain and obstacle detection data; mapping terrain and obstacles in real time based on the terrain and obstacle detection data; calculating a collision potential area based on the mapped data; calculating a deceleration area based on the mapped data and a speed of the mobility assistance device; receiving user preferences regarding the deceleration area and desired direction and speed of movement; calculating a command to command movement of the mobility assistance device based on the potential collision area, the deceleration area, the user preferences, and combinations thereof; moving the mobility assistance device based on the command; A method comprising:

2. The method described in claim 1, wherein the collision probability area is calculated based on an area containing at least one obstacle from the obstacle detection data.

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