Vehicle active suspension control system and method

Abstract

Aspects of the invention relate to a method and control system for controlling an active suspension of a vehicle, the control system comprising one or more controllers, the control system being configured to: determine whether a transient suspension disturbance to the vehicle is from within a cabin of the vehicle; and control a variable force parameter of the active suspension in dependence on whether the transient suspension disturbance is from within the cabin of the vehicle.

Description

Technical Field

[0001] This disclosure relates to active suspension control systems and methods for vehicles. Specifically, but not exclusively, this disclosure relates to active suspension control systems and methods for road vehicles. Background Technology

[0002] Active suspension for vehicles is known. Active suspension includes hydraulically actuated suspension, electro-hydraulic suspension, pneumatic suspension, and electromagnetic suspension. Active suspension may include active dampers (shock absorbers) and / or active springs. Active suspension offers the advantage that spring forces and / or damping forces can be varied using a control system during use. This achieves an adaptive trade-off between comfort and improved road handling. The increasing automation of vehicles, including shared mobility vehicles such as taxis, presents new challenges and opportunities for improving passenger comfort. Summary of the Invention

[0003] The purpose of this invention is to address one or more of the disadvantages associated with the prior art.

[0004] The aspects and embodiments of the present invention provide control systems, methods, vehicles, and computer software as claimed in the appended claims.

[0005] According to an aspect of the invention, a control system for controlling an active suspension of a vehicle is provided, the control system comprising one or more controllers configured to: determine whether a transient suspension disturbance to the vehicle originates from within the vehicle's passenger compartment; and control variable force parameters of the active suspension based on whether the transient suspension disturbance originates from within the vehicle's passenger compartment. An advantage is that the vehicle provides a more stable platform for passenger compartment load transfer, wherein a more stable platform is advantageous.

[0006] Controlling the variable force parameters can include changing the upper limit of the variable force parameters. Changing the upper limit can include increasing the upper limit of the variable force parameters when it is determined that the transient suspension disturbance originates from inside the vehicle's cabin, and not increasing the upper limit when it is determined that the transient suspension disturbance does not originate from inside the vehicle's cabin. The advantage is improved motion perception, as occupants continue to feel the vehicle's movement under external disturbance sources.

[0007] The variable force parameter may include force requirements, and wherein the force requirements include spring force requirements and / or damping force requirements.

[0008] Variable force parameters can be functions of the detected roll and / or pitch and / or heel-drop angles of the vehicle body relative to the wheels.

[0009] The variable force parameter can be the output of the top hook controller and / or the bottom hook controller.

[0010] Determining whether a transient suspension disturbance originates from within the vehicle cabin can include at least one of the following operations: monitoring the cabin using one or more cabin sensors; monitoring detected vehicle roll and / or pitch and / or heave angles; comparing the transient suspension disturbance with a monitored anticipated transient suspension disturbance correlated with the vehicle's planned cornering and / or planned acceleration and / or planned braking and / or planned speed and / or monitored external environmental conditions; or monitoring displacement using wheel-to-body displacement sensors. The advantage is a reduction in false positives.

[0011] The control system can be configured to: determine whether there are no occupants in the vehicle; and when it is determined that there are no occupants in the vehicle, decrease the variable force parameter, and when it is determined that there are not no occupants in the vehicle, not decrease the variable force parameter. The advantage is energy savings when there are no occupants in the vehicle.

[0012] The control system can be configured to: determine whether a suspension disturbance to the vehicle is associated with mechanical resonance; and when it is determined that the suspension disturbance is associated with mechanical resonance, control the variable force parameters to change the natural frequency associated with the active suspension, and when it is determined that the suspension disturbance is not associated with mechanical resonance, not perform the operation of controlling the variable force parameters to change the natural frequency. The advantage is improved stability, as the vehicle is less likely to roll over.

[0013] According to another aspect of the present invention, a vehicle including a control system is provided.

[0014] In some examples, the vehicles are configured for autonomous driving.

[0015] According to another aspect of the present invention, a method for controlling an active suspension of a vehicle is provided, the method comprising: determining whether a transient suspension disturbance of the vehicle originates from inside the vehicle's passenger compartment; and controlling variable force parameters of the active suspension based on whether the transient suspension disturbance originates from inside the vehicle's passenger compartment.

[0016] According to another aspect of the invention, computer software is provided that, when executed, is arranged to perform any one or more of the methods described herein.

[0017] According to another aspect of the invention, a control system is provided, which is configured to perform any one or more of the methods described herein.

[0018] One or more controllers may collectively include: at least one electronic processor having an electrical input for receiving information indicating transient suspension disturbances; and at least one electronic memory device electrically coupled to the at least one electronic processor and having instructions stored in the at least one electronic memory device; and wherein the at least one electronic processor is configured to access the at least one memory device and execute the instructions on the at least one memory device such that the control system controls the active suspension based on the information.

[0019] Within the scope of this application, it is expressly intended that all aspects, embodiments, examples, and alternatives set forth in the foregoing paragraphs, claims, and / or the following description and drawings, and in particular their various features, may be employed individually or in any combination. That is, all embodiments and / or features of any embodiment may be combined in any manner and / or combination, unless such features are incompatible. The applicant reserves the right to amend any initially filed claim or accordingly file any new claim, including the right to modify any initially filed claim to be subordinate to any other claim and / or incorporate any feature of any other claim, even if not initially claimed in this manner. Attached Figure Description

[0020] One or more embodiments of the invention will now be described by way of example only, with reference to the accompanying drawings, in which:

[0021] Figure 1 An example of a vehicle is shown;

[0022] Figure 2A An example of a control system is shown, while Figure 2B An example of a non-transitory computer-readable medium is shown;

[0023] Figure 3 An example of a vehicle's cargo compartment is shown;

[0024] Figure 4 An example of a system for vehicles is shown;

[0025] Figure 5 An example of a control method is shown;

[0026] Figure 6A An example is shown where the vehicle tilts to the left to provide a positive superelevation effect against lateral acceleration in the leftward direction, while Figure 6B An example is shown where the vehicle tilts to the right to provide a positive superelevation effect against lateral acceleration in the rightward direction;

[0027] Figure 7 An example of a control method is shown;

[0028] Figure 8A An example of a vehicle pitching in the first rotational direction under positive longitudinal acceleration is shown, while Figure 8B An example of a vehicle pitching in the second rotational direction under negative longitudinal acceleration is shown;

[0029] Figure 9 An example of a control method is shown;

[0030] Figure 10 An example of a control method is shown;

[0031] Figure 11 An example of a control method is shown;

[0032] Figure 12 An example of a control method is shown;

[0033] Figure 13A An example of a vehicle providing a horizontal entry / exit platform on a transverse ramp is shown, while Figure 13B An example of a vehicle that provides a horizontal entry / exit platform on a longitudinal ramp is shown;

[0034] Figure 14 An example of a control method is shown;

[0035] Figure 15A An example is shown where the vehicle does not tilt to match the camber angle of the entry / exit surfaces, while Figure 15B An example is shown where the vehicle is tilted to match the camber angle of the in / out surface;

[0036] Figure 16 An example of a control method is shown;

[0037] Figure 17 An example is shown where the vehicle lowers its passenger height as it approaches the traction battery charging port; and

[0038] Figure 18 An example of a control method is shown. Detailed Implementation

[0039] Figure 1 Examples of road vehicles 10 (referred to herein as "vehicles") that can implement embodiments of the present invention are shown. In some, but not all, examples, vehicle 10 is a passenger vehicle, also called a bus or car. In other examples, vehicle 10 may be a freight vehicle, such as a truck. Buses and trucks typically have a curb weight of less than 4000 kg. Buses and trucks typically have a length of less than 7 meters. In other examples, embodiments of the present invention can be implemented for other applications, such as industrial or commercial vehicles.

[0040] Figure 1An onboard 3D coordinate system defining three vertical axes and Euler angles is also shown. The coordinate system includes a longitudinal x-axis. The vehicle 10 is configured to travel in the positive x-direction (positive acceleration) and reverse in the negative x-direction (negative acceleration = deceleration). The x-axis also defines a roll axis. It will be understood that the vehicle includes a body that comprises a passenger compartment suspended via a suspension system disposed between the body and the wheels. The action of the suspension system provides relative vertical movement between the wheels and the body, which in turn allows for a degree of controlled body roll and body pitch relative to the wheels.

[0041] The coordinate system includes a lateral y-axis. Vehicle 10 is configured to steer during motion to apply lateral acceleration along the y-axis. Vehicle 10 is configured to steer left in the positive y-direction and right in the negative y-direction. The y-axis also defines a pitch axis. Vehicle 10 can be configured for front-wheel steering, rear-wheel steering, or four-wheel steering. Vehicle 10 can be configured to lateralize using rack and pinion steering / Ackerman steering, etc. In some examples, vehicle 10 can be configured to lateralize via steering yaw (e.g., sideslip, roll) of vehicle 10.

[0042] The coordinate system includes a vertical z-axis. The seating height of vehicle 10 increases in the positive z-direction and decreases in the negative z-direction. Vehicle lifting and lowering is movement along the z-axis. The z-axis also defines the yaw axis.

[0043] Figure 2A A control system 2 is shown. The control system 2 includes one or more controllers. As an example, a controller 20 is shown.

[0044] Figure 2A The controller 20 includes: at least one electronic processor 22; and at least one electronic memory device 24 electrically coupled to the electronic processor 22 and having instructions 26 (e.g., a computer program) stored therein, said at least one electronic memory device 24 and instructions 26 being configured to utilize the at least one electronic processor 22 to cause one or more of the methods described herein to be executed. An example controller 20 of the control system 2 is an active suspension controller for controlling actuators of an active suspension.

[0045] Figure 2B A non-transitory computer-readable storage medium 28 including instructions 26 (computer software) is shown.

[0046] Figure 3 An example of vehicle 10 is shown, illustrating a passenger compartment 300 and a powertrain. The passenger compartment 300 shown includes the interior of vehicle 10, which is at least partially surrounded by the body 302 of vehicle 10. Access to passenger compartment 300 is possible through at least one door 304. Door 304 may be a sliding door or a swing door.

[0047] The carriage 300 includes passenger seats 306 for seated passengers. The carriage 300 may include handles 308 for standing passengers. Handles 308 may be grip handles. The grip handles 308 for standing passengers may be located in an area inaccessible from the seats 306. Standing passengers are more likely than seated passengers to lose their balance due to unexpected vehicle movement.

[0048] In the illustration, at least one passenger seat 306 faces a different direction than at least one other passenger seat 306. The seats 306 shown face opposite directions. This seating arrangement provides more interior legroom and luggage space, and offers more personal space for passengers who are unfamiliar with each other. However, passengers not directly facing the direction of travel of the vehicle 10 are more likely to experience motion sickness and / or be less able to anticipate vehicle movement.

[0049] Figure 3 A layout is shown in which at least one seat 306 or a row of seats 306 is located above the axle of the vehicle 10. In this example, the axle corresponds to a pair of laterally separated wheels. Passengers located above or suspended above the axle experience greater lift (z-axis translation) from vehicle suspension movement compared to passengers located within the wheelbase of the vehicle 10.

[0050] The carriage arrangement shown is an example of many possible carriage arrangements.

[0051] In the alternative example, vehicle 10 is a cargo vehicle. If vehicle 10 is an autonomous vehicle, the cargo compartment 300 may include fewer seats, or no passenger seats. Some cargo may be fragile and sensitive to excessive cargo compartment acceleration.

[0052] In some examples, Figure 3 Vehicle 10 may be a shared mobility vehicle. The shared mobility vehicle may include a billing module (not shown) for determining the bill for the trip based on automatic monitoring of time and / or distance. If the vehicle is driverless, customer payments may be processed via an onboard payment terminal and / or via automatic (e.g., geofence-triggered) communication with an external server (e.g., a ride-hailing application) that manages user accounts and payments. The billing module may issue tickets or receipts via an onboard printer and / or via automatic communication.

[0053] In some, but not all, examples, shared mobility vehicles can be implemented as pod cars. A pod car is defined herein as a shared mobility vehicle configured for limited occupancy and comprising three or more wheels, compared to a bus or train. For example, depending on the implementation, a pod car can have space for one to six occupants. A pod car may include one to six seats. A pod car can be configured to travel at a predetermined maximum speed in pedestrian-only areas. A pod car can be configured to travel on roads at or above a predetermined maximum speed.

[0054] according to Figure 3 However, not necessarily in all examples, vehicle 10 includes a traction battery 312 and an electric traction motor 310. Therefore, vehicle 10 can be a fully electric vehicle (EV) or a hybrid electric vehicle (HEV). In other examples, vehicle 10 may include an internal combustion engine or other torque sources. Vehicle 10 can even be gravity-driven and may not have a torque source. In some, but not necessarily all, examples, vehicle 10 can be a non-road vehicle, such as a rail vehicle, a magnetic levitation vehicle, etc.

[0055] Figure 4 The diagram illustrates a system 400 for vehicle 10, including a control system 2, sensors, interfaces, and actuators. Vehicle 10 may be... Figure 1 and Figure 3 10 vehicles.

[0056] Vehicle 10 includes active suspension 402, an example of which is shown in Figure 4 As shown in the diagram, the active suspension 402 can be configured for active damping. Active damping can be controlled using a pump-controlled hydraulic circuit or equivalent. Impact forces and / or rebound forces can be individually controllable.

[0057] The active suspension 402 can be configured for active spring control. Active spring control can be controlled using a pump-controlled pneumatic system or equivalent. Spring force (spring stiffness) can be controllable. Ride height can be controllable. The active suspension 402 can achieve active roll control and / or active pitch control on one or more axles.

[0058] The active suspension 402 can be controlled by the control system 2, optionally via another lower-level controller. In some, but not all, examples, the active suspension 402 can be controlled using variable force parameters. The variable force parameters control the degree to which the active suspension 402 prevents movement of the vehicle 10's cabin / body. The variable force parameters can be force requirements (gains). Force requirements can include spring force requirements for controlling spring stiffness, and / or damping force requirements for controlling impact and / or rebound forces. Control of the suspension fluid pump and / or flow limiter (damping) can depend on the force requirements. Increasing the force requirements increases the spring force and / or damping force, resulting in a "stiffer" suspension. A single force requirement can control the active suspension setup for multiple wheels or for a single wheel.

[0059] Force demand can be a function of detected carriage motion. Detecting carriage motion can include monitoring inertial signals indicating carriage motion, such as roll and / or pitch and / or rise and fall.

[0060] The force requirements described above can be negotiated force requirements depending on multiple individual force requirements requested by multiple controllers. These controllers can include predictive controllers and reactive controllers. Controllers can include overhead hook controllers and / or ground hook controllers. The negotiated force requirements can be calculated by combining individual force requirements, for example, based on addition, prioritization, and / or averaging. The overhead hook controller approximates a situation where the vehicle body maintains a stable attitude relative to the sky and is therefore unaffected by ground conditions. It will be understood that the scenario where the vehicle body is completely unaffected by ground conditions is impractical, and therefore the overhead hook controller will approximate this condition while considering energy and other real-world requirements. The ground hook controller achieves the same goal by controlling the wheels relative to the ground, making the vehicle body unaffected by ground conditions.

[0061] Figure 4 The active suspension 402 of system 400 includes one or more active components, such as active dampers and / or active springs, for each wheel FL, FR, RL, RR. The active suspension 402 may be a semi-active suspension with active dampers and passive springs or active springs and passive dampers. Subsystems of the active suspension 402 are not shown and may be provided in any suitable arrangement for the desired control of the active suspension 402 required to implement one or more of the methods described herein.

[0062] Vehicle 10 may be an autonomous vehicle. Vehicle 10 may be a fully autonomous vehicle. A fully autonomous vehicle 10 is a driverless vehicle configured for autonomous driving only. A fully autonomous vehicle 10 may lack an accelerator pedal, brake pedal, and / or steering wheel. Therefore, a fully autonomous vehicle may lack a identifiable driver's seat. The vehicle may be configured for Level 5 automated driving as defined in SAE Standard J3016.

[0063] Alternatively, vehicle 10 may include a lower-level autonomous driving mode and a non-autonomous driving mode for at least one driving task (steering / acceleration / braking).

[0064] The control system 2 is configured to receive sensor-dependent information directly or indirectly from the sensors, enabling the control system 2 to control the active suspension 402 based on the current vehicle environment. Figure 4 An example sensor involved in the method described herein is shown, which includes:

[0065] - Inertial Measurement Unit (IMU 408). IMU 408 provides indications of carriage movement. For example, IMU 408 can indicate roll, pitch, and / or rise.

[0066] - At least one passenger compartment sensor 410. The passenger compartment sensor 410 can provide indications of vehicle occupancy and / or occupant behavior. The passenger compartment sensor 410 may include at least one of the following: a passenger compartment camera for imaging vehicle occupants in the passenger compartment 300; a seat belt sensor for detecting whether seat belts are fastened; a seat weight sensor for detecting whether a seat is occupied, etc.

[0067] - At least one positioning sensor 406. The positioning sensor 406 provides information that enables an autonomous vehicle controller (not shown) to locate the vehicle 10 in the driving environment. Therefore, the autonomous vehicle controller plans vehicle maneuvers (acceleration and / or braking and / or steering) of the vehicle 10 based on the positioning sensor information. Maneuver planning may include applying cost / reward functions associated with obstacle avoidance and travel requirements based on the positioning sensor information. At least one positioning sensor 406 may include an onboard, outward-facing vision system (e.g., camera, lidar, radar) for imaging the environment surrounding the vehicle 10 within a specific range (e.g., 50 to 500 m) and a specific field of view (e.g., 360 degrees). Additionally or alternatively, at least one positioning sensor 406 may include an interface for vehicle-to-vehicle (V2V) or vehicle-to-infrastructure (V2I) communication.

[0068] --At least one wheel sensor. The wheel sensor provides an indication of the suspension status of a particular wheel. The wheel sensor includes: a wheel-to-body displacement sensor 404 for sensing suspension compression / extension (indicating force); a wheel position sensor; a wheel hub accelerometer, etc.

[0069] - At least one user interface 412. The user interface 412 shown is an in-vehicle user interface, i.e., an occupant interface. The vehicle compartment 300 may include a human-machine interface to provide the occupant interface. The occupant interface may include an entry / exit request button for requesting the autonomous vehicle 10 to stop and allowing the user to disembark. The occupant interface may include a door open / close button. The occupant interface may include a touchscreen display / voice interface for receiving user-dependent information, such as preferences and / or journey requirements. In some examples, at least one user interface 412 may be configured to interface with a user device such as a smartphone, wherein the user device includes a human-machine interface for at least one of the above functions.

[0070] The term “user” as described in this document refers to the current, potential, or previous occupant (passenger) of vehicle 10.

[0071] In the example use case, the above system 400 enables users to input travel requirements, such as a destination (exit location) and an optional pick-up location (entry location). The control system can be configured to generate user-relevant routes that meet the travel requirements. Therefore, the routes and any entry / exit locations are configurable to define the self-organizing shared mobility vehicle 10 (e.g., autonomous taxi).

[0072] The following describes various methods for using the active suspension 402. These methods can be implemented individually or in combination for better results.

[0073] Motion feedback

[0074] Figure 5 and Figure 7 Control methods 500 and 700 are shown to improve comfort and signal to occupants that acceleration is about to begin. These methods deliver small, perceptible movements (referred to herein as “motor feedback”) to the occupant and signal that larger acceleration is about to begin. Studies have shown that humans are better able to anticipate head movements when perceptible motor feedback is provided, rather than auditory / visual / tactile feedback. This is because motor feedback triggers the vestibular system to begin using closed-loop muscle control before larger acceleration begins. Auditory / visual / tactile stimulation only results in less effective feedforward muscle control, and undesirable head acceleration may occur before vestibular control transitions to a closed loop.

[0075] Figure 5 The control method 500 involves lateral acceleration, while Figure 7Control method 700 involves longitudinal acceleration. These two control methods can be summarized as methods 500 and 700 for improving comfort, which include:

[0076] Receive information indicating the required positive or negative vehicle acceleration on the first axle; and

[0077] Before vehicle acceleration begins, based on received instructions, the active suspension 402 begins to modify the body angle around a second axis perpendicular to the first axis. Early timing provides motion feedback.

[0078] Another benefit of methods 500 and 700 is that the reference frame of carriage 300 rotates relative to the direction of vehicle acceleration, thus reducing the non-vertical acceleration component and increasing the vertical (head-to-toe) component. This reduces head jerk.

[0079] Motion feedback for lateral acceleration

[0080] Figure 5 The lateral acceleration control method 500 begins at block 502, receiving information indicating a requirement for vehicle acceleration, wherein the vehicle acceleration includes lateral acceleration. In the example, the method utilizes this information to predict the future lateral acceleration of vehicle 10. The information indicating a requirement for vehicle acceleration may include information indicating a requirement for acceleration of an autonomous vehicle. This information may come from an autonomous vehicle controller responsible for planning maneuvers such as turning. In some examples, vehicle 10 may be driven non-autonomously, and this information may be based on sensing of the environment surrounding vehicle 10, for example, through an externally oriented vision system, to predict the requirement for lateral acceleration.

[0081] An optional decision box is shown. At decision box 504, method 500 includes determining the magnitude of the desired vehicle acceleration. The method requires at least that the magnitude is above a threshold. If the magnitude is determined to be above the threshold, method 500 continues. If the magnitude is determined to be below the threshold, method 500 terminates at box 514.

[0082] Similar to box 504, method 500 can determine the duration of the desired vehicle acceleration (not shown in the flowchart). This method requires the duration to be at least above a threshold. If the duration is above the threshold, method 500 continues. If the duration is below the threshold, method 500 terminates. The duration threshold can vary based on the amplitude, and / or the amplitude threshold can vary based on the duration, for example, via a control chart.

[0083] At decision box 506, method 500 includes determining whether another condition, which at least requires the method to satisfy, is met. This condition is related to the proximity of the completion of vehicle acceleration in the lateral axis to the start of subsequent vehicle acceleration in the lateral axis. If this condition is met, the suspension angle may not have enough time to return to its unmodified state before the next motion feedback begins, and therefore method 500 will terminate. If this condition is not met, method 500 continues.

[0084] One way to implement box 506 involves planning motion feedback for more than one lateral maneuver in front of vehicle 10. Satisfaction of a condition may require the maneuver to be within a threshold proximity. In a particular example, the threshold proximity may define an overlap point. Overlap is defined as the predetermined completion time of the motion feedback for the first maneuver (completion of a return rotation) occurring after a predetermined start time of the motion feedback for the subsequent maneuver. If adjacent motion feedback events do not overlap, the condition is satisfied, and method 500 continues. If they overlap, the condition is not satisfied, and method 500 may terminate. In some examples, the condition may be checked if both maneuvers satisfy box 504 (sufficient amplitude). In some examples, the condition may be checked if the maneuver involves lateral acceleration in opposite directions (e.g., a turnaround curve).

[0085] At decision box 508, method 500 includes determining whether the desired lateral acceleration is positive (e.g., left) or negative (e.g., right) lateral acceleration. This allows control method 500 to tilt (leverage) the vehicle body in the direction of rotation, providing a positive superelevation effect to the vehicle occupants. The positive superelevation effect increases the head-to-toe component of acceleration and reduces the lateral acceleration perceived by the vehicle occupants.

[0086] If the lateral acceleration is determined to be to the left (positive y-axis), then method 500 proceeds to block 510, which includes controlling the active suspension 402 to begin moving the vehicle body around the roll axis (x-axis) in the first rotational direction ( Figure 6A Inclined in a counter-clockwise direction, such as Figure 6A As shown. This reduces the lateral acceleration experienced by vehicle occupants during cornering. In some, but not necessarily all, examples of roll modification make the body less parallel to the surface beneath the body around the roll axis.

[0087] If the lateral acceleration is determined to be to the right (negative y-axis), then method 500 proceeds to block 512, which includes controlling the active suspension 402 to begin moving the vehicle body around the roll axis (x-axis) in the second rotational direction ( Figure 6B Inclined in a clockwise direction, such as Figure 6B As shown. This reduces the lateral acceleration experienced by vehicle occupants during cornering.

[0088] The tilting at boxes 510 and 512 can include modifying the angle in the above-mentioned rotational direction before the vehicle's lateral acceleration begins to provide perceptible motion feedback, and then returning to the unmodified angle by modifying the angle in the return rotational direction no earlier than the start of the vehicle's lateral acceleration. The return to the unmodified angle can be at different rates. The tilting rate in the return rotational direction can be different, for example, slower. In a specific implementation, the tilting rate in the return rotational direction can be half the tilting rate before the start of the vehicle's lateral acceleration. This helps the occupants understand that a return rotation is occurring, rather than a new rotation at another corner.

[0089] The rate (velocity, acceleration, and / or jerk) and / or magnitude (angular displacement) of tilt before the initiation of vehicle acceleration at boxes 510 and 512 may optionally depend on the magnitude of the lateral acceleration. A first acceleration magnitude may cause a first rate / magnitude of tilt change. A second acceleration magnitude may cause a second rate / magnitude of tilt change. In some examples, the rate / degree of tilt may be proportional to the magnitude of the lateral acceleration. This proportion may include multiple granularity levels. The proportion allows the user to anticipate greater acceleration. The rate / degree of tilt may be limited (saturated) when a predetermined limit (e.g., a second acceleration magnitude) is reached. If the acceleration magnitude reaches a third acceleration magnitude greater than the second acceleration magnitude, the tilt change may be limited to a second rate / magnitude. The predetermined limit may be calibrated to avoid occupant discomfort.

[0090] The tilting at frames 510 and 512 can be accompanied by perceptible auditory / visual / tactile feedback entering the passenger compartment 300, such as via speakers, displays, or haptic actuators, to increase passenger anticipation of lateral acceleration. Additional feedback can be output at a predetermined time prior to acceleration.

[0091] According to method 500 above, motion feedback must begin at least before lateral acceleration begins. Tilt can begin at a predetermined time before vehicle acceleration begins, where the predetermined time ranges from approximately 0.5 seconds to approximately 2 seconds. The lower limit provides the user with sufficient time to anticipate an upcoming corner. The upper limit considers the uncertainty of planning maneuvers in unknown environments and, for rapidly changing environments, can even be 1 second or less. The predetermined time can be a fixed single value or it can be variable.

[0092] In an alternative to the above method 500, tilting can begin simultaneously with or after the initiation of lateral acceleration to reactively provide active superelevation without forward motion feedback. Therefore, according to an aspect of the invention, a method is also provided, comprising: receiving information indicating a requirement for positive or negative vehicle acceleration on a first axle, wherein the first axle is a lateral axis; and, based on the received indication, controlling an active suspension 402 to begin modifying an angle of the vehicle body about a second axle perpendicular to the first axle, wherein the second axle is a longitudinal axis and the angle is roll.

[0093] Lateral acceleration itself can be controlled to be smooth. For example, the speed and path of vehicle 10 can be autonomously controlled to minimize the comfort cost function and / or avoid exceeding predetermined acceleration and / or jerk thresholds.

[0094] Motion feedback for longitudinal acceleration

[0095] Now refer to Figure 7 The longitudinal acceleration control method 700 provides motion feedback before the onset of positive or negative longitudinal vehicle acceleration, so as to prepare and inform the occupants of the upcoming acceleration.

[0096] Method 700 begins at block 702, receiving information indicating a requirement for vehicle acceleration, wherein the vehicle acceleration includes longitudinal acceleration. In the example, this information predicts the future longitudinal acceleration of vehicle 10. The information indicating a requirement for vehicle acceleration may include information indicating a requirement for acceleration of an autonomous vehicle. This information may come from an autonomous vehicle controller responsible for planning maneuvers such as acceleration and braking. In some examples, vehicle 10 may be driven non-autonomously, and this information may predict the requirement for longitudinal acceleration based, for example, sensing of the environment surrounding vehicle 10 via an externally oriented vision system.

[0097] An optional decision box is shown. At decision box 704, method 700 includes determining whether the acceleration is associated with the transition between a stopped state and a moving state of vehicle 10. In this example, method 700 at least requires the transition. If it is determined that the acceleration is associated with the transition between the stopped and moving states, method 700 continues. If it is determined that the acceleration is not associated with the transition between the stopped and moving states, method 700 terminates at box 714.

[0098] As a result of box 704, method 700 is performed only when accelerating from a stop and / or decelerating to a stop. Acceleration from a stop / to a stop is associated with higher jerk, such as due to friction brake grip and / or due to torque path gap crossing, thus making earlier motion feedback more favorable.

[0099] In the alternative implementation, box 704 is omitted, and motion feedback is applied regardless of whether vehicle 10 is stopped. Vehicle 10 can move before and after acceleration.

[0100] At decision box 706, method 700 includes determining the magnitude of the desired vehicle acceleration. Method 700 requires the magnitude to be at least above a threshold. If the magnitude is determined to be above the threshold, method 700 continues. If the magnitude is determined to be below the threshold, method 700 terminates at box 714.

[0101] Similar to box 706, method 700 can determine the duration of the desired vehicle acceleration (not shown in the flowchart). Method 700 requires the duration to be at least above a threshold. If the duration is above the threshold, method 700 continues. If the duration is below the threshold, method 700 terminates. The duration threshold can vary based on the amplitude, and / or the amplitude threshold can vary based on the duration, for example, via a control chart.

[0102] At decision box 708, method 700 includes determining whether the requested acceleration is positive (e.g., forward acceleration) or negative (e.g., deceleration / reduction). This allows control method 700 to pitch the vehicle body in a specific rotational direction to indicate whether the upcoming acceleration is positive or negative. Pitch reduces the non-vertical acceleration component at the user's location, thereby reducing head jerk.

[0103] If the longitudinal acceleration is determined to be positive (positive x-axis), then method 700 proceeds to block 710, which includes controlling the active suspension 402 to begin pitching the vehicle body about the pitch axis (y-axis) in a first rotational direction, such as... Figure 8A As shown. In some, but not necessarily all, examples of pitch modification make the vehicle body less parallel to the surface beneath it around the pitch axis. Pitching the body provides motion feedback and reduces the longitudinal acceleration experienced by vehicle occupants during acceleration. According to Figure 8A According to the physics of weight transfer under positive acceleration, the first direction of rotation is the pitch direction (rear descent and / or front rise). However, occupants less familiar with vehicle physics might find it more intuitive if the first direction of rotation is the dive direction (rear rise and / or front descent). Therefore, depending on the implementation, the first direction of rotation can be either pitch or dive.

[0104] If the longitudinal acceleration is determined to be negative (negative x-axis), then method 700 proceeds to block 712, which includes controlling the active suspension 402 to begin pitching the vehicle body about the pitch axis (y-axis) in the second rotational direction, such as... Figure 8B As shown. The second direction of rotation is opposite to the first direction of rotation. Pitching the vehicle provides motion feedback and reduces the longitudinal deceleration experienced by the vehicle occupants during deceleration.

[0105] The pitch at frames 710 and 712 may include modifying the angle in the first rotational direction mentioned above before vehicle acceleration begins to provide motion feedback, and then returning to the unmodified angle by modifying the angle in the return rotational direction no earlier than the start of vehicle acceleration. The return to the unmodified angle may be performed at the same or different rates.

[0106] The pitch modification rate at boxes 710 and 712 is controlled to provide perceptible motion feedback, thereby triggering biological closed-loop balance control. According to the example, for most implementations, the average pitch modification rate in the first rotational direction is approximately 2 degrees per second, or a value of about 1 degree per second. Different implementations require different rates, and in the example, this rate is a value ranging from approximately 0.5 degrees per second to approximately 5 degrees per second to provide perceptible motion feedback without excessive z-axis movement, such as heave or sag.

[0107] The rate (velocity, acceleration, and / or jerk) and / or magnitude (angular displacement) of pitch toward the modified angle in the first rotational direction at frames 710 and 712 may optionally depend on the magnitude of the longitudinal acceleration. A first acceleration magnitude may cause a first rate / magnitude of pitch change. A second acceleration magnitude may cause a second rate / magnitude of pitch change. In some examples, the rate / magnitude of pitch may be proportional to the magnitude of the longitudinal acceleration. This proportion may include multiple granularity levels. The proportion allows the user to anticipate greater acceleration. When a predetermined limit (e.g., a second acceleration magnitude) is reached, the rate / magnitude of tilt may be limited (saturated). If the acceleration magnitude reaches a third acceleration magnitude greater than the second acceleration magnitude, the pitch change may be limited to the second rate / magnitude. The predetermined limit may be calibrated to avoid occupant discomfort.

[0108] Pitch at frames 710 and 712 can be accompanied by perceptible auditory / visual / tactile feedback entering the passenger compartment 300, such as via speakers, displays, or haptic actuators, to increase passenger anticipation of longitudinal acceleration. Additional feedback can be output at a predetermined time after the door 304 has closed and before acceleration.

[0109] According to method 700 above, motion feedback must begin at least before longitudinal acceleration begins. Pitch can begin at a predetermined time before vehicle acceleration begins, wherein the predetermined time is in the range of approximately 0.5 seconds to approximately 2 seconds. The lower limit provides the user with sufficient time to anticipate the upcoming longitudinal acceleration. The upper limit takes into account the uncertainty of planning maneuvers in unknown environments and, for rapidly changing environments, can even be 1 second or less. The predetermined time can be a fixed single value or it can be variable. The predetermined time for longitudinal acceleration can be the same as or different from the predetermined time for lateral acceleration.

[0110] The longitudinal acceleration itself can be controlled to be smooth. For example, the speed and path of vehicle 10 can be autonomously controlled to minimize the comfort cost function and / or avoid exceeding predetermined acceleration and / or jerk thresholds.

[0111] The aforementioned longitudinal acceleration control method 700 and lateral acceleration control method 500 can be combined for combined tilt and pitch, such as tilting and pitching simultaneously, to further improve the expected acceleration and further reduce non-vertical head acceleration.

[0112] Compensation for load on moving carriages

[0113] Figure 9 Another control method 900 for improving occupant comfort according to another aspect of the present invention is shown. Figure 9 This is an example of implementing method 900, which includes:

[0114] Determine whether the transient suspension disturbance originates from within the passenger compartment 300 (frame 902) of vehicle 10; and

[0115] The variable force parameters of the active suspension 402 are controlled based on whether the transient suspension disturbance originates from inside the passenger compartment 300 of the vehicle 10 (box 904).

[0116] Suspension disturbances are forces transmitted through the active suspension 402. A transient disturbance occurs when the force associated with at least one wheel changes. A transient suspension disturbance can correspond to a single change in force, an irregular sequence of forces, or it can have an associated frequency.

[0117] In this use case, passengers prefer a vehicle that doesn't sway when weight moves back and forth within the passenger compartment 300. Using variable force parameters can advantageously approach eliminating sway. However, if the variable force parameters are controlled to the same extent as the source of suspension disturbances outside the passenger compartment 300, the vehicle compartment 300 may feel too isolated from the road, which could contribute to motion sickness. Depending on the source of the external suspension disturbances (e.g., road undulations, potholes, bumps, textures, etc.), allowing some passenger compartment movement can alleviate motion sickness.

[0118] Figure 9 Method 900 begins at box 902 and includes determining whether a transient suspension disturbance originates from within the passenger compartment 300 of vehicle 10. If it is determined that the transient suspension disturbance originates from within the passenger compartment 300, method 900 continues. If it is determined that the transient suspension disturbance does not originate from within the passenger compartment 300 (e.g., external / unknown), method 900 terminates at box 906.

[0119] The transient suspension disturbance can be detected or predicted. Control system 2 may include a predictive controller for predictively controlling the active suspension 402 based on the predicted transient suspension disturbance. Control system 2 may also include a reactive controller for reactively controlling the active suspension 402 based on the detected transient suspension disturbance. Control system 2 may include both a predictive controller and a reactive controller, wherein the reactive controller compensates for erroneous predictions by the predictive controller. Figure 9 Method 900 can be implemented using predictive controllers, reactive controllers, or a combination thereof.

[0120] In the example, when a transient suspension disturbance exceeds a threshold amplitude and / or a threshold rate of suspension disturbance, method 900 can determine whether the disturbance originates from within the passenger compartment 300 of vehicle 10. Method 900 may require at least that the amplitude / rate be above the threshold.

[0121] Using appropriate sensors makes it possible to detect or predict transient suspension disturbances. An example is provided.

[0122] IMU 408 can be monitored to detect vehicle roll, pitch, and / or height. Signals from wheel-to-vehicle displacement sensor 404 can also detect transient suspension disturbances. The raw signals are independent of the source of the suspension disturbance. However, the signals can be compared with reference data to determine the source. When vehicle 10 is unloaded, the control system can record IMU / displacement data of vehicle 10 over time to provide reference data. The control system can compare the data of vehicle 10 when loaded with the reference data of vehicle 10 when unloaded and look for discrete disturbances in pitch, roll, and / or height and / or wheel-to-vehicle displacement.

[0123] If a cabin sensor 410, such as a camera device, is present, image analysis can be performed to identify the source of detected or predicted disturbances. For example, objects such as people or goods can be identified. Motion identifiers, such as vectors, can be associated with the object. Based on the motion identifiers, detected or predicted transient suspension disturbances from the cabin 300 can be determined.

[0124] Other cabin sensors 410 include vehicle occupancy sensors, such as seatbelt sensors, seat weight pressure sensors, and floor pressure sensors. Loosening the seatbelt and / or changing seat weight corresponds to a source of transient suspension disturbance detected or predicted at a known location within the vehicle 10. Another cabin sensor 410 includes an acoustic sensor.

[0125] Information from the user interface 412 can be used. For example, the user device can indicate its (and the user's) presence inside the vehicle. Pressing the door open / close button can indicate a detected or predicted transient suspension disturbance.

[0126] In some examples, the control system 2 can identify whether the source of a transient suspension disturbance is outside the vehicle compartment 300 in order to determine whether the source originates from the vehicle compartment 300. Analysis of the IMU 408 and / or the wheel-to-body displacement sensor 404 can identify external sources. The positioning sensor 406 enables the detection / prediction of external sources of transient suspension disturbances. Wind speed and / or direction sensors can be used to determine the contribution of wind to the movement of the vehicle compartment.

[0127] In some examples, control system 2 may monitor anticipated transient suspension disturbances associated with handling planning to determine whether the source originates from passenger compartment 300. Anticipated transient suspension disturbances may include anticipated cornering and / or acceleration and / or braking and / or speed of vehicle 10. Handling planning is performed using positioning sensor 406. If control system 2 associates a transient suspension disturbance with an anticipated transient suspension disturbance by comparison, the transient suspension disturbance does not originate from passenger compartment 300.

[0128] In some examples, block 902 can be determined deterministically based on at least one sensor independent of the source of the disturbance. The aforementioned compartment sensor 410 and / or user interface 412 implement the deterministic method.

[0129] In some examples, box 902 can be determined probabilistically. This determination can depend on multiple sensing modes (a combination of the aforementioned sensors / analysis). This determination may include combining the combined probabilities from multimodal information with probability thresholds associated with different sources of transient suspension disturbances.

[0130] If the transient suspension disturbance originates within the passenger compartment 300, then method 900 proceeds to block 904. Block 904 includes the variable force parameters controlling the active suspension 402. The variable force parameters can be the force requirements described above.

[0131] The force demand itself may remain irrelevant whether the transient suspension disturbance originates from within or outside the passenger compartment 300. However, controlling the force demand at block 904 may include altering the upper limit of the force demand. This upper limit can be increased. Increasing the upper limit advantageously allows the control system 2 to control passenger compartment-induced sway while responding consistently to other smaller disturbances, thereby increasing occupant comfort. If the passenger compartment-induced disturbance is less severe than predicted, the limit will not be reached, and the vehicle 10 will continue to behave in a predictable manner. Occupants may not notice any compromise in vehicle behavior and may feel as if they are in a vehicle 10 that inherently does not sway during occupant / cargo movement. This lack of sway provides the feeling of sitting in a large-mass vehicle like a bus, which is advantageous for customers accepting smaller-sized autonomous vehicles. However, in an alternative implementation of method 900, block 904 may increase the force demand itself.

[0132] Increasing the upper limit can include increasing the upper limit of spring force and / or damping force, depending on which part of the active suspension is active. The upper limit of spring force can be the same as or different from the upper limit of damping force.

[0133] Energy saving mode

[0134] Figure 10 Another control method 1000 for improving occupant comfort according to another aspect of the present invention is shown. Control method 1000 includes:

[0135] Determine whether there are no occupants on vehicle 10 (box 1002); and

[0136] The variable force parameter is reduced when it is determined that there are no occupants on vehicle 10 (box 1004), and not reduced when it is determined that there are not no occupants on vehicle 10 (box 1006). Box 1006 may result in the implementation of other control methods described herein.

[0137] The determination of whether there are no occupants on vehicle 10 can be performed using the cabin sensor 410 and / or the user interface and / or the wheel-to-body displacement sensor 404. For example, no occupants are in the vehicle if: image analysis of the cabin camera device identifies no occupants; all seat weight sensors indicate weight below a threshold; all seatbelt sensors indicate seatbelts are unfastened; no user-related (passenger-related) journey request is active; wheel-to-body displacement meets the no-load condition; etc.

[0138] Reducing variable force parameters can include reducing force demand (gain). Reducing gain, such as the hook / slip gain, reduces energy consumption. For example, in a pump-controlled fluid active suspension, lower gain requires less pump operation. Gain can be reduced to lower, non-zero values. In some examples, reducing variable force parameters can include shutting down the pump.

[0139] Stability against resonant disturbances

[0140] Figure 11 Another control method 1100 for improving vehicle stability according to another aspect of the present invention is shown. Control method 1100 includes:

[0141] Determine whether transient suspension disturbances are associated with mechanical resonance (box 1102); and

[0142] When it is determined that a transient suspension disturbance is associated with mechanical resonance, the variable force parameters are controlled to change the natural frequency associated with the active suspension 402 (box 1104), and when it is determined that a transient suspension disturbance is not associated with mechanical resonance, the variable force parameters are not controlled to change the natural frequency (box 1106).

[0143] The control method 1100 alters the natural frequency to a harmonic natural frequency that is not a mechanical resonance. This makes the vehicle 10 more difficult to overturn, for example, by vandals or thugs. Due to a lack of oversight, a fully driverless vehicle may be more susceptible to intentional damage than a vehicle with a driver.

[0144] Determining whether transient suspension disturbances are associated with mechanical resonance can be achieved in various ways. Time analysis can be used to analyze the time variations of the IMU 408 and / or wheel-to-vehicle displacement signals to detect mechanical resonance.

[0145] In some implementations, association can be made by identifying the source of the transient suspension disturbance. If the source includes pushing the body 302 of the vehicle 10, then association is made. Detection of the push can be achieved using image analysis from images from a cabin camera (through a transparent window) and / or an externally facing vision system and / or using pressure sensors in the body 302 / vehicle cabin 300.

[0146] If an increase in the amplitude of the vibration is detected as part of a mechanical resonance, block 1104 can be executed. If the oscillation decreases or does not increase, the control system 2 can determine not to execute block 1104, at least unless / until the amplitude of the oscillation increases.

[0147] Controlling variable force parameters to change the natural frequency associated with the active suspension 402 can be achieved in various ways. Changing the natural frequency can include changing the force demand of at least one wheel. The force demand can correspond to spring force and / or damping force. The natural frequency can be changed once or multiple times in response to a single determination. In some examples, the natural frequency can be changed multiple times within a predetermined time period.

[0148] The change in natural frequency can be arbitrary or determined by the closed-loop control process. In some examples, the modified natural frequency can be controlled to be out of phase with the mechanical resonance based on closed-loop feedback. The closed-loop control process may include determining the force requirement needed to provide peak resistance to the amplified mechanical resonance, and then providing that force requirement.

[0149] Horizontal platform on the slope

[0150] Figure 12 Another control method 1200 for improving vehicle accessibility according to another aspect of the present invention is shown. Control method 1200 includes at least:

[0151] Receive information indicating passenger and / or cargo entry / exit requests (box 1202);

[0152] Receive information indicating that vehicle 10 will enter / exit on the inclined surface 1300 (box 1204); and

[0153] The active suspension 402 is controlled to reduce the angle of the vehicle body relative to the horizontal plane for entry / exit on the inclined surface 1300 (frames 1212 or 1214).

[0154] Method 1200 enables vehicle 10 to provide a level platform, horizontal to the horizon, before entering / exiting, for example, before door 304 is opened. This makes entering and exiting steep mountains easier and prevents cargo from slipping or tilting. The ability to provide a level platform is limited by the maximum suspension travel.

[0155] The inclined surface 1300 may include a lateral ramp, wherein the active suspension 402 is configured to tilt the vehicle body about a roll axis (x-axis) to reduce the angle of the vehicle body relative to the horizontal plane, such as... Figure 13A As shown. Alternatively or additionally, the inclined surface 1300 may include a longitudinal ramp, wherein the active suspension 402 is configured to pitch the vehicle body about a pitch axis (y-axis) to reduce the angle of the vehicle body relative to the horizontal plane, such as Figure 13B As shown.

[0156] There are multiple methods for determining an entry / exit request. For example, user interface 412 can enable a user to request entry / exit. The user can press an entry / exit request button. The user can press a door open / close button. The user's request can come from the human-machine interface of vehicle 10 or from their user device. Depending on whether the request is for entry or exit, the user may or may not be an occupant of vehicle 10.

[0157] Entry / exit requirements can be determined based on other user-related information such as journey requirements. For example, the navigation function of control system 2 can determine that vehicle 10 has arrived at the destination specified by the journey requirements (e.g., a geofence).

[0158] Once the instruction to request has been received, for block 1204, method 1200 receives information indicating that vehicle 10 will enter / exit on the inclined surface 1300. For example, this information may be based on monitoring of the driving environment by positioning sensor 406. This information may be based on monitoring map data including slope information.

[0159] Decision box 1204 may include determining whether vehicle 10 will enter / exit on inclined surface 1300. If vehicle 10 will enter / exit on inclined surface 1300, method 1200 continues. If not, method 1200 terminates at box 1216, maintaining an angle substantially parallel to the non-inclined surface for entry / exit.

[0160] The determination of box 1204 can be reactive or predictive. Predictive determination allows the active suspension 402 to be gently controlled while the vehicle 10 is still moving. Reactive determination can be performed when the vehicle 10 is approaching or coming to a stop.

[0161] Making a reactive determination may include using an inclinometer to monitor signals. The accelerometer of IMU 408 can be used as an inclinometer. Predictive determinations can be made based on determining the entry / exit position within the driving environment and the slope at the entry / exit point. Determining whether a surface is tilted may include monitoring input from positioning sensor 406 and / or querying map data with slope information.

[0162] Decision box 1206 includes determining the magnitude of the surface slope. Method 1200 requires the amplitude to be at least above a threshold. If the amplitude is above the threshold, method 1200 continues. If the amplitude is below the threshold, method 1200 terminates. This is because a horizontal platform is more advantageous for steeper slopes. The amplitude can be determined from IMU 408, map data, positioning sensor 406, or a combination thereof.

[0163] Decision box 1208 includes polling information indicating at least one in / out characteristic. In this example, method 1200 does not need to obtain such information by polling. If such information is not obtained, method 1200 continues. If such information is obtained, method 1200 terminates. The method continues when there is no reason based on the user to maintain an angle parallel to the inclined surface 1300.

[0164] An example of information indicating at least one entry / exit characteristic includes a wheel entry / exit requirement associated with pushing an object onto / off the vehicle. Pushing an object such as a person, cargo, or stroller frame onto vehicle 10 may require a ramp. In some examples, the wheel entry / exit requirement may be a wheelchair entry / exit requirement and / or a stroller entry / exit requirement. The human-machine interface at vehicle 10 and / or user device may be configured to allow the user to input the wheel entry / exit requirement. If the user inputs the requirement, the condition is not met, and method 1200 terminates. Alternatively, the wheel entry / exit requirement can be detected using image processing from images from a vehicle-mounted camera or an externally facing vision system, by recognizing objects such as wheelchairs or strollers.

[0165] Another example of information indicating at least one entry / exit characteristic includes loading / unloading cargo requirements associated with loading goods onto / unloading goods from a vehicle. Loading / unloading cargo requirements may include manual loading / unloading requirements and / or machine loading / unloading requirements. Manual loading is easier when the cargo area entrance point (e.g., a door) is low to the ground. Machine loading is easier if the vehicle body is at the same angle as the machine. The machine may be a forklift or other machine. A dedicated human-machine interface may be provided to allow a user to input loading / unloading cargo requirements. If the user inputs, the condition is not met, and method 1200 terminates. Alternatively, image processing from images from a vehicle-mounted camera or an externally facing vision system may be used to detect whether loading / unloading of cargo is in progress, and if so, whether the cargo is being loaded / unloaded manually or by machine.

[0166] Decision box 1210 includes determining whether the surface is inclined in a first direction or in a second, opposite direction. In one example, the first direction could be an uphill slope on a longitudinal ramp. The second direction could be a downhill slope on a longitudinal ramp. Active suspension 402 can be controlled differently based on whether the surface is inclined uphill or downhill, as shown in the figure. In an alternative implementation, the amount of angle change is independent of the direction of the slope.

[0167] If the surface slopes upward, method 1200 proceeds to block 1212, whereby block 1212 controls the active suspension 402 to reduce the angle of the vehicle body relative to the horizontal plane until a first limit is reached. If the surface slopes downward, method 1200 proceeds to block 1214, whereby block 1214 controls the active suspension 402 to reduce the angle of the vehicle body relative to the horizontal plane to a second limit. The second amount can be less than the first amount to ensure that occupants can still see the ground from the front windshield of vehicle 10, thereby reducing directional obstruction.

[0168] Controlling the active suspension 402 as described in boxes 1212 and 1214 may include determining the angular difference between the vehicle and a horizontal plane (e.g., a virtual horizon associated with an inclinometer). The control system 2 may be configured to determine the difference and control the active suspension 402 to reduce it. Whether the difference can be eliminated is constrained by the maximum suspension travel.

[0169] The control of the reduction angle of the active suspension 402 can begin after the vehicle 10 has stopped, or at a threshold time before the vehicle 10 stops.

[0170] Curb matching and kneeling

[0171] Figure 14 Another control method 1400 for improving vehicle accessibility according to another aspect of the present invention is shown. Control method 1400 includes at least:

[0172] Determine the height difference and / or angle difference between the vehicle body and the entry / exit surface 1500 (box 1402); and

[0173] Control the active suspension 402 to reduce the height difference, and / or control the active suspension 402 to reduce the angle difference of the vehicle body (box 1410 or 1412).

[0174] The method 1400 described above provides a kneeling function to reduce the size of the steps a user must take when entering / exiting the vehicle 10. The entry / exit surface 1500 can be a road surface (sidewalk) or other location where the user will step onto or leave the vehicle 10 and is not beneath the vehicle 10. The entry / exit surface 1500 can be approached by detecting a curb. Alternatively, the entry / exit surface 1500 can be determined by recognizing the road surface and / or by recognizing where a person is standing via an outward-facing vision system. The location of the entry / exit surface 1500 can be determined based on travel requirements (destination / pickup location) and location information to find a suitable parking spot.

[0175] Using the curb example, method 1400 can lower the seating height for lower curbs. Method 1400 can increase the seating height for higher curbs. If the angle differs from the surface to which the vehicle 10 stops for entry / exit, the vehicle roll angle can be adjusted to match the camber angle of the entry / exit surface 1500, and / or the vehicle pitch angle can be adjusted to match the longitudinal slope of the entry / exit surface 1500. Typically, the road surface has a different camber angle than the road, and the curb rises and falls regularly relative to the road surface.

[0176] Optionally, method 1400 and... Figure 12 Method 1200. If so, the difference in angles can be controlled to avoid relative to boxes 1212 or 1214 (reducing the angle to the horizontal plane). For example, the difference in angles could be about an axis (e.g., x-axis, tilt), while Figure 12 The difference between the reduction of method 1200 and the horizontal plane is about another axis (e.g., the y-axis, pitch).

[0177] The height / angle difference between the vehicle body and the entry / exit surface 1500 can be determined in various ways. The position of the entry / exit surface 1500 can be determined. Information indicating the height / angle of the entry / exit surface 1500 can be determined. 3D point cloud / depth map or other positioning information can be used. For curbs, simpler curb height detectors also exist. Information indicating the height / angle of the vehicle body at the entry / exit position 10 can be determined in a similar manner. The difference between the height and / or angle can be determined. Optionally, this difference may need to exceed at least a minimum threshold for method 1400 to continue.

[0178] and Figure 12Similar to box 1208 of method 1200, optional decision box 1404 polls for information indicating at least one in / out characteristic.

[0179] Optional box 1406 includes receiving information indicating the camber angle of entry / exit from surface 1500. Camber angle refers to the lateral slope away from the side of vehicle 10, for example, the slope in the y-axis direction if vehicle 10 is parked parallel to the x-axis and facing forward. The camber angle information can be determined using the techniques mentioned above for box 1402. Active suspension 402 can be controlled differently depending on the camber angle. For example, if the camber angle is downward (negative z-axis, where the distance from the y-axis of vehicle 10 increases), method 1400 can reduce the angle difference, such as... Figure 15B As shown, this is to reduce the step distance with the vehicle. If the camber angle is positive (positive z-axis, where the y-axis distance from vehicle 10 increases), then method 1400 can terminate at box 1410 without reducing the angle difference, as... Figure 15A As shown, the angle difference can be reduced to a lesser extent. In an alternative embodiment, the angle difference is independent of the direction of the camber angle, and / or the angle does not change at all.

[0180] Inductive charging

[0181] Figure 16 Another control method 1600 for improving vehicle comfort according to another aspect of the present invention is shown. Control method 1600 includes at least:

[0182] Receive information indicating that vehicle 10 will arrive at traction battery charging interface 1700 (box 1602); and

[0183] Based on the received information, as vehicle 10 approaches the traction battery charging port 1700 and before vehicle 10 reaches the traction battery charging port 1700, the active suspension 402 is controlled to begin modifying the vehicle body's height and / or angle relative to multiple wheels towards the desired height and / or angle associated with traction battery charging. Figure 17 As shown.

[0184] In some, but not all, examples, the traction battery charging interface 1700 is configured for wireless inductive charging. The charging interface 1700 may include a charging pad. The charging interface may include a charging coil that can be mounted to the underside of the vehicle body and arranged to inductively couple with the charging pad to charge the traction battery. The required height / angle can be a set point for wireless inductive charging. This set point can be used to optimize resonant inductive coupling. The set point height / angle provides the highest charging efficiency. Changing not only the height but also the angle advantageously enables efficient charging on rough and uneven surfaces, such as public roads.

[0185] The charging port 1700 can be located on or below the road surface where the vehicle 10 travels. The charging port 1700 can be located at waiting locations where the vehicle 10 frequently stops temporarily, such as taxi stands or traffic light queues. During each journey, the vehicle 10 may be served by multiple charging ports 1700. Therefore, the traction battery 312 can receive periodic, small charging boosts throughout its journey while stopped. This helps allow vehicles such as taxis to operate for longer periods. However, if the height / angle begins to change after the vehicle 10 reaches the charging port 1700, occupants may notice. This can be unexpected and uncomfortable. Therefore, the height / angle begins to change before the vehicle 10 reaches the charging port 1700.

[0186] For block 1602, receiving information indicating that vehicle 10 will arrive at traction battery charging interface 1700 can be implemented in various ways. Control system 2 can determine whether vehicle 10 is arriving at charging interface 1700. If it is determined that vehicle 10 has arrived at charging interface 1700, method 1600 can continue. Otherwise, method 1600 can terminate. The location of charging interface 1700 can be indicated in map data or, for example, via sign recognition from externally oriented vision system data. The route of vehicle 10 can be known from driving plans and user-related journey requirements. The route can be matched with the location of the charging interface. It can be determined that vehicle 10 is arriving at charging interface 1700 based on a threshold proximity of vehicle 10 to charging interface 1700. In this example, method 1600 requires at least vehicle 10 to reach the threshold proximity. The threshold proximity can be defined using geofencing, the time taken to reach charging interface 1700, or a combination thereof.

[0187] Method 1600 includes an optional decision box. Box 1604 includes determining whether vehicle 10 can stop to charge the traction battery via charging interface 1700. If it is determined that vehicle 10 can stop to charge the traction battery via charging interface 1700, method 1600 continues. Otherwise, method 1600 terminates. This decision is performed if vehicle 10 must stop for charging. In an implementation, the future stopping position of vehicle 10 is known from autonomous driving planning. If the stopping position coincides with the charging interface position, method 1600 continues. The stopping position can be determined based on monitored traffic light status, monitored movement rates of other road users, etc. If vehicle 10 can charge while moving, box 1604 can be omitted, or box 1604 can be implemented to determine whether the speed of vehicle 10 at the charging position will be below a threshold.

[0188] Decision box 1606 includes determining the expected duration for which vehicle 10 will be operatively coupled to traction battery charging interface 1700. In this example, method 1600 requires at least a duration greater than a threshold. If the duration is greater than the threshold, method 1600 continues. If the duration is less than the threshold, method 1600 terminates. The duration can be represented using time-related parameters. Time-related parameters can be represented as the time elapsed, or as the predicted amount of charge to be obtained at charging interface 1700, etc.

[0189] In some examples, determining the expected duration depends on monitoring at least one of the following: traffic movement associated with the path of vehicle 10; or monitoring of dynamic right-of-way information. The path of vehicle 10 is known from the maneuvering plan. For example, traffic movement can be monitored by monitoring a queue that vehicle 10 is in or approaching. Location sensor information can be used to monitor traffic movement. Dynamic right-of-way information indicates traffic lights, priority signs, and other road instructions along vehicle 10's path that provide conditional and / or timed right-of-way to different traffic flows. If the traffic light will be green or the queue is moving well, vehicle 10 may not be able to charge. If vehicle 10 must wait in a queue, vehicle 10 may be able to charge.

[0190] In the traffic light use case, the charging interface 1700 is associated with a traffic light, and checking the duration may include determining traffic light parameters that indicate how long the traffic light will indicate red / yield once the vehicle 10 arrives at the charging interface 1700. The traffic light parameters may be obtained via, for example, V2I communication with a traffic light controller. For the pedestrian crossing use case, checking the duration may include determining pedestrian crossing utilization based on location sensor information.

[0191] Determining the expected duration may include determining the usage status of vehicle 10. The usage status may depend on the number of detected vehicle occupants. In some examples, the usage status may depend on a timetable, such as a schedule and time of day. The expected duration may increase when vehicle 10 is unoccupied and / or not providing service and / or during off-peak hours.

[0192] In some examples, vehicle 10 may stop at one or more predetermined stopping locations, such as taxi stands or passenger stands, that have inductive charging capability. Determining the expected duration may include determining information associated with the stopping location, such as the class of the stopping location (e.g., a taxi stand rather than a passenger stand), the average stopping duration at the stopping location, etc.

[0193] Another optional determination (not shown) may include determining whether the current for the predicted state of charge of the traction battery 312 is below a threshold. In this example, method 1600 requires at least that the state of charge is below a threshold. If the state of charge is below the threshold, method 1600 may continue. If the state of charge is above the threshold, method 1600 may terminate. The threshold may be a value in the range of 80% to 100% of a full charge. The prediction may be journey-related, i.e., based on user-dependent journey requirements.

[0194] Once all the above requirements are met, box 1608 includes controlling the active suspension 402 to begin modifying the vehicle's height / angle toward a set point. In this use case, the vehicle's passenger height is typically higher than the optimal height for wireless inductive charging while driving. Therefore, box 1608 may at least include reducing the average height (passenger height) of the vehicle 10. A passenger height in the range of 60 to 100 mm is typically associated with efficient wireless inductive charging.

[0195] Control system 2 can determine a predetermined time before reaching charging interface 1700, starting block 1608. The predetermined time is at least about 0.5 seconds. In some examples, the predetermined time is a value ranging from about 0.5 seconds to 10 seconds. A longer time allows for a slower rate of change to achieve comfort, but there is a greater likelihood of abort if conditions change unexpectedly. Shorter times, towards 0.5 to 1 second, provide a greater probability for vehicle 10 to move and decelerate at the start of active suspension control. Therefore, the cabin acceleration associated with starting block 1608, and especially jerk, is an imperceptible component of the composite cabin acceleration / jerk associated with deceleration force and road-induced cabin motion. Determining whether the predetermined time has been reached to reach charging interface 1700 may include determining the distance to charging interface 1700 divided by the predicted speed of vehicle 10. The predicted speed and distance may be known from handling planning and / or map data.

[0196] The rate of highly modified parameters can be controlled to be below a threshold or limit to achieve comfort.

[0197] Since vehicle 10 has not yet reached charging port 1700, the setpoint height / angle can be initially calculated via an open-loop control process. The open-loop setpoint may be the same or different for each charging port 1700. If different, the open-loop setpoint for each charging port 1700 can be determined using historical data of previous values ​​of the setpoint during previous charging at the charging port 1700. The setpoint can be determined based on the charging of other vehicles using V2V communication. The setpoint can be provided via V2I communication.

[0198] Once vehicle 10 has reached charging interface 1700, closed-loop feedback on charging efficiency can be used to further control the setpoint, thereby further optimizing resonant inductive coupling and finding peak charging efficiency.

[0199] Frame 1610 includes initiating charging of vehicle 10 via charging interface 1700. Charging can begin once the on-board charging interface 1702 of vehicle 10 is aligned longitudinally (x-axis) and / or laterally (y-axis) with charging interface 1700. Charging can begin before or after vehicle 10 reaches a set point in height and / or angle.

[0200] Box 1612 includes receiving information indicating that vehicle 10 will leave traction battery charging interface 1700 and stop traction battery charging. Box 1612 can determine whether this information has been received during charging. This information can be received by monitoring traffic movement associated with the path of vehicle 10 and / or monitoring dynamic right-of-way information such as traffic lights.

[0201] Once the information from block 1612 is received, method 1600 proceeds to block 1614, which includes controlling the active suspension 402 to achieve a second desired height and / or angle for the vehicle 10 that is independent of the charging of the traction battery. The second desired height and / or angle is independent of the charging port 1700. The second desired height / angle may be the same as or similar to the height / angle prior to block 1608.

[0202] Box 1614 can be controlled to begin after the vehicle 10 has started moving away from the traction battery charging interface 1700, so that the vehicle occupants will hardly notice it. The rate of change toward the second desired height / angle can be different from the rate associated with box 1608.

[0203] It should be understood that in other implementations of the method 1600 described above, charging technologies other than wireless inductive charging can be used. For example, the charging interface can be configured to make current contact with a contactor on the vehicle 10, and changing the height / angle of the vehicle 10 can achieve this current contact.

[0204] Methods 1200 and 1400 for entering / exiting can have a higher priority than method 1600 for inductive charging. When vehicle 10 stops at charging port 1700, the control system can determine whether entering / exiting will occur. For example, the control system can determine whether an entering / exit request has been received. If entering / exiting will occur, method 1600 can terminate before block 1608. Methods 1200 and / or 1400 can be performed alternatively. In some examples, after entering / exiting is completed and when vehicle 10 stops at charging port 1700, the suspension can be lowered for inductive charging (block 1608).

[0205] Lock in place

[0206] Figure 18 Another control method 1800 for improving vehicle accessibility according to another aspect of the present invention is shown. Control method 1800 includes at least:

[0207] Receive information instructing vehicle 10 to come to a complete stop (box 1802); and

[0208] Upon receiving information that the vehicle 10 has come to a standstill, the force of the active suspension 402 (frame 1806) is increased.

[0209] When occupants may get on or off the vehicle 10 or move back and forth within the passenger compartment 300 while the vehicle 10 is stationary, the increased force provides a stiffer, more stable platform. This stiffer platform results in less body sway. This lack of sway provides the feel of a large, bus-like vehicle, which is advantageous for customer acceptance of smaller autonomous vehicles. Reduced sway also reduces the chance of accidental collisions between the user and the body 302 of the vehicle 10 during entry / exit.

[0210] In block 1802, receiving information indicating that vehicle 10 has come to a standstill can be implemented in various ways. Control system 2 can determine whether vehicle 10 is transitioning from a moving state to a standing (stopped) state. If yes, method 1800 continues. If not, method 1800 terminates. The indication information can be detected or predicted. Detecting that vehicle 10 has come to a standstill can include, for example, detecting that vehicle 10 has come to a standstill from wheel speed signals. Predicting that vehicle 10 has come to a standstill can be achieved through maneuver planning.

[0211] In some, but not necessarily all, examples, control system 2 may determine whether vehicle 10 is stopping for entry / exit and execute method 1800 only when entry / exit is about to occur. This is because entry / exit is associated with a larger load moving to or from carriage 300.

[0212] An optional decision box 1804 is shown, which includes determining the duration for which vehicle 10 is stationary. This method requires at least a duration greater than a threshold. If the duration is greater than the threshold, method 1800 continues. If the duration is less than the threshold, method 1800 may terminate at box 1812. The duration can be a detected duration for which vehicle 10 has been stationary, and the threshold can be a value ranging from, for example, about 0.5 seconds to about 5 seconds. The duration can also be a predicted duration for which vehicle 10 will be stationary, and the threshold can be a value of at least about 5 seconds.

[0213] Then, method 1800 proceeds to block 1806 and increases the force on the active suspension 402. Increasing the force may include increasing the aforementioned variable force parameters. For example, increasing the force may include increasing the force requirement, which could include increasing the spring force requirement and / or the damping force requirement. In other examples, the active suspension 402 may include a strut lowered toward the ground to increase the overall force of the active suspension 402.

[0214] In one implementation, block 1806 may include determining whether vehicle 10 has come to a standstill, for example to confirm a previous prediction. If vehicle 10 is detected to be stationary, the force is increased. By increasing the force no earlier than when vehicle 10 has come to a stop, occupants will not experience any increase in cabin vibration or harshness associated with a stiffer suspension while vehicle 10 is coming to a stop.

[0215] At box 1808, method 1800 includes receiving information instructing vehicle 10 to begin moving. Similar to box 1802, the information can be predictive or detected. Upon receiving the instruction information, the force can be reduced in the return direction. At box 1810, in response to box 1808, the force is reduced to a normal "driving" value, which is the same as or similar to the force prior to box 1806.

[0216] Many of the methods described above involve controlling suspension height and / or angle. This creates the possibility that the suspension height will be lowered. Therefore, optional determinations can be performed before controlling the suspension height and / or angle. This determination can indicate the minimum achievable height of vehicle 10. This determination can depend on the road surface detected at the charging port. This determination can depend on the sensing of protrusions such as bumps, bulges, or objects via the vehicle 10's outward-facing vision system.

[0217] Any change in height can be limited to lowering the active suspension 402 at one or more corners of vehicle 10 to a height not lower than a minimum height. Additionally or alternatively, the method can be terminated if the predetermined minimum height is a result of detected objects on the road (whether classified or not), or if the predetermined minimum height is higher than a threshold. In some examples, lowering the ride height while vehicle 10 is moving may be accompanied by increasing the variable force parameter.

[0218] The various thresholds and preset times described in the methods described herein can be fixed or variable. Fixed thresholds / fixed preset times can be determined through calibration to reduce uncomfortable suspension variations. Variable thresholds / variable preset times can be user-dependent or environment-dependent.

[0219] All the control methods described above are executed by the control system 2 as described above. Therefore, the control methods are limited to computer-implemented methods. The steps of the methods can be executed centrally or distributed across multiple networked control systems.

[0220] The reference to control system 2 determining whether a condition (decision box) is met includes any of the following: control system 2 obtains raw, unprocessed data and makes a determination internally; and control system 2 obtains an externally determined result. The reference to control system 2 receiving information indicating the environment as described above includes any of the following: control system 2 obtains raw, unprocessed data and determines internally whether the environment exists; and control system 2 obtains an externally determined result indicating that the environment exists.

[0221] For the purposes of this disclosure, it should be understood that the controllers 20 described herein may each include control units or computing devices having one or more electronic processors 22. The vehicle 10 and / or its control system 2 may include a single control unit or electronic controller, or alternatively, different functions of the controller may be embodied in or hosted in different control units or controllers. A set of instructions 26 may be provided, which, when executed, causes the controller or control unit to implement the control techniques (including the methods) described herein. This set of instructions may be embedded in one or more electronic processors, or alternatively, may be provided as software to be executed by one or more electronic processors. For example, a first controller may be implemented in software running on one or more electronic processors, and one or more other controllers may also be implemented in software running on one or more electronic processors, optionally in software running on the same one or more processors as the first controller. However, it should be understood that other arrangements may be used, and therefore this disclosure is not intended to be limited to any particular arrangement. In any case, the set of instructions described above may be embedded in a computer-readable storage medium (e.g., a non-transitory computer-readable storage medium), which may include any mechanism for storing information in a form readable by a machine or electronic processor / computing device, including but not limited to: magnetic storage media (e.g., floppy disks); optical storage media (e.g., CD-ROMs); magneto-optical storage media; read-only memory (ROM); random access memory (RAM); erasable programmable memory (e.g., EPROMs and EEPROMs); flash memory; or electronic or other types of media for storing such information / instructions.

[0222] It should be understood that various changes and modifications can be made to this invention without departing from the scope of this application.

[0223] The boxes shown in the flowchart may represent steps in a method and / or code portions in computer program 26. The description of a specific order of boxes does not necessarily imply a required or preferred order, and the order and arrangement of boxes can vary. Furthermore, it is possible to omit some steps.

[0224] Each paragraph described as "aspects of the invention" is an independent statement suitable for the present or future independent claims and does not require additional features.

[0225] Although embodiments of the invention have been described with reference to various examples in the foregoing paragraphs, it should be understood that modifications may be made to the given examples without departing from the scope of the claimed invention.

[0226] In addition to the explicitly described combinations, the features described above can be used in combination.

[0227] Although various functions have been described with reference to certain features, these functions can be performed by other features, regardless of whether other features are described.

[0228] Although features have been described with reference to certain embodiments, these features may also exist in other embodiments, whether or not they have been described.

[0229] Although the foregoing specification focuses on those features of the invention that are considered particularly important, it should be understood that the applicant claims protection for any patentable features or combinations thereof mentioned above and / or shown in the drawings, whether or not they are specifically emphasized.

Claims

1. A control system for controlling an active suspension of a vehicle, the control system comprising one or more controllers, the control system being configured to: Determine whether the transient suspension disturbance of the vehicle originates from inside the vehicle's passenger compartment; and The variable force parameters of the active suspension are controlled based on whether the transient suspension disturbance originates from inside the vehicle's passenger compartment. in, Controlling the variable force parameter includes changing the upper limit of the variable force parameter. The modification of the upper limit includes: increasing the upper limit of the variable force parameter when it is determined that the transient suspension disturbance originates from inside the vehicle's passenger compartment, and not increasing the upper limit when it is determined that the transient suspension disturbance does not originate from inside the vehicle's passenger compartment. The variable force parameter includes force requirements, and the force requirements include spring force requirements and / or damping force requirements.

2. The control system according to claim 1, wherein, The one or more controllers collectively include: At least one electronic processor, the at least one electronic processor having an electrical input for receiving information indicating transient suspension disturbances; and At least one electronic memory device, the at least one electronic memory device being electrically coupled to the at least one electronic processor and storing instructions in the at least one electronic memory device; Furthermore, the at least one electronic processor is configured to access the at least one memory device and execute instructions on the at least one memory device to cause the control system to control the active suspension based on the information.

3. The control system according to any of the preceding claims, wherein, The variable force parameters are functions of the detected roll angle and / or pitch angle and / or rise / fall relative to the wheels of the vehicle body.

4. The control system according to any of the preceding claims, wherein, The variable force parameter is the output of the top hook controller and / or the bottom hook controller.

5. The control system according to any of the preceding claims, wherein, Determining whether the transient suspension disturbance originates from within the vehicle's passenger compartment includes at least one of the following operations: The carriage is monitored using one or more carriage sensors; Monitor the detected roll angle and / or pitch angle and / or rise of the vehicle; The transient suspension disturbance is compared with the monitored expected transient suspension disturbance, which is associated with the vehicle’s planned cornering and / or planned acceleration and / or planned braking and / or planned speed and / or the monitored external environment of the vehicle. or Displacement is monitored using wheel-to-vehicle displacement sensors.

6. The control system according to any of the preceding claims is configured to: Determine whether there are no occupants in the vehicle; and When it is determined that there are no occupants in the vehicle, the variable force parameter is reduced; and when it is determined that there are occupants in the vehicle, the variable force parameter is not reduced.

7. The control system according to any of the preceding claims is configured to: Determine whether the suspension disturbance of the vehicle is associated with mechanical resonance; and When it is determined that the suspension disturbance is associated with mechanical resonance, the variable force parameter is controlled to change the natural frequency associated with the active suspension, and when it is determined that the suspension disturbance is not associated with mechanical resonance, the variable force parameter is not controlled to change the natural frequency.

8. A vehicle comprising a control system according to any of the preceding claims.

9. The vehicle according to claim 8, wherein, The vehicle is configured for autonomous driving.

10. A method for controlling an active suspension of a vehicle, the method comprising: Determine whether the transient suspension disturbance of the vehicle originates from inside the vehicle's passenger compartment; as well as The variable force parameters of the active suspension are controlled based on whether the transient suspension disturbance originates from inside the vehicle's passenger compartment. Controlling the variable force parameter includes changing the upper limit of the variable force parameter. The modification of the upper limit includes: increasing the upper limit of the variable force parameter when it is determined that the transient suspension disturbance originates from inside the vehicle's passenger compartment, and not increasing the upper limit when it is determined that the transient suspension disturbance does not originate from inside the vehicle's passenger compartment. The variable force parameter includes force requirements, and the force requirements include spring force requirements and / or damping force requirements.

11. A computer software, which, when executed, is configured to perform the method according to claim 10.

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