System and method for speed control of wheels of a vehicle

Abstract

Systems and methods are provided herein for controlling a speed on each wheel of a vehicle, possibly operating the vehicle in a speed control mode. In response to receiving an input to enter the speed control mode and receiving an accelerator pedal input, the system determines a target wheel speed based on the accelerator pedal input, monitors a wheel speed of each wheel of a plurality of wheels, and determines a difference for each monitored wheel based on the monitored wheel speed and the target wheel speed. Torque is provided to each wheel of the plurality of wheels based on the respective difference to achieve the target wheel speed.

Description

[0001] introduction

[0002] Vehicles typically perform turns by allowing the driver to turn the front wheels. However, the radius of such turns is limited by the degree to which the wheels can turn, making it difficult to perform turns on narrow roads or paths. Additionally, in vehicles, the accelerator pedal typically adjusts the engine's output power, which can produce variable wheel speeds based on surface conditions (e.g., due to wheel slippage), potentially making turns difficult and driving on terrain challenging. Therefore, there is a need for better vehicle control for turning and for driving on uneven, variable, and surfaces with varying friction, among various other types of surfaces. Summary of the Invention

[0003] Advantageously, a speed control system is provided to the vehicle to control the speed of each wheel based on accelerator pedal input. In some embodiments, the speed control system is a system that operates when all wheels are at the same wheel speed. In some embodiments, the speed control system associates accelerator pedal input with a target wheel speed. For example, a single accelerator pedal input can provide appropriate torque to each wheel to achieve the target wheel speed. The torque provided to each wheel can vary based on uneven, variable, and different friction surfaces (such as, for example, driving on an uneven surface or an icy road) to achieve the target wheel speed.

[0004] In one approach, the system determines a target wheel speed based on accelerator pedal input and monitors the wheel speed of each wheel (e.g., at least two wheels) on the vehicle. In some embodiments, torque may be provided proportionally to the accelerator pedal input (e.g., the degree to which the user has pressed the accelerator pedal, the degree to which the accelerator pedal is pressed to the bottom, and other possibilities envisioned herein) and the difference between the target wheel speed and the monitored wheel speed. In some embodiments, torque may be provided to achieve the target wheel speed based on a lookup table. Therefore, this speed control system is able to better control each wheel of the vehicle located on uneven, variable, and varying friction surfaces by maintaining the target wheel speed.

[0005] Furthermore, in this method, the system determines whether there is a difference between the target wheel speed and the monitored wheel speed. For example, when the current wheel is on a low-friction surface (e.g., loose dirt, gravel roads, wet surfaces, snowy roads, and other terrain), it may exceed the target wheel speed; however, when the rear wheel is on a high-friction surface (e.g., dry roads, road surfaces, and other drive surfaces), it may not reach the target wheel speed. In some embodiments, in response to determining the difference between the monitored wheel speed and the target wheel speed, the system adjusts the torque for each of the multiple wheels so that the monitored wheel speed is closer to the target wheel speed.

[0006] In some implementations, the speed control system determines that the wheel speed of one of the vehicle's wheels exceeds a target wheel speed. In some implementations, for one of the wheels, in response to determining that the monitored wheel speed exceeds the target wheel speed, the system can reduce the power supplied to the electric motor of that wheel to reduce the wheel speed and better control each wheel of the vehicle.

[0007] Furthermore, it is advantageous to provide speed control to the wheels of a vehicle to better control wheel speed on uneven, variable, unstable, and different surfaces. For example, the vehicle may be positioned on an uneven surface (e.g., inclined, downhill, tilted to one side) and may be situated on a surface with varying friction (e.g., a surface with rain, snow, ice, mud, road surface, gravel, wet surface). According to this disclosure, systems and methods are provided to improve vehicle control by employing speed control modes. A speed control mode is a mode in which the speed of each wheel is controlled and adjusted to match a target wheel speed. In some embodiments, the methods and systems may utilize improved features of the vehicle (e.g., independent control of the front and rear drive axles, independent control of each wheel in the wheels, independent control of each brake in the brakes, etc.) to perform speed control at each wheel. Thus, the methods and systems can provide the vehicle with the ability to perform smooth and controlled rotation (in either direction) about a point under the vehicle chassis, while using speed control at each wheel for controlled driving on uneven or unstable surfaces with varying surface friction, enabling the vehicle to pivot in a circle with a minimum or zero radius of rotation. Zero-radius rotation is a rotation that causes the vehicle to pivot around a point beneath it.

[0008] In some implementations, the techniques described below can be executed by the vehicle's processing circuitry. The processing circuitry can be implemented as part of the vehicle, integrated within the vehicle's electronic circuitry, or otherwise. In some embodiments, the processing circuitry may include an onboard vehicle computer capable of controlling multiple features or capabilities of the vehicle. In some embodiments, the processing circuitry may be communicatively connected to the vehicle's user inputs, infotainment system, vehicle sensors, and transient or non-transitory memory (e.g., memory storing mechanisms for operating the vehicle).

[0009] In some embodiments, the vehicle includes an independent motor for each of the wheels. In some embodiments, the respective motors may include electric motors. For example, the vehicle may have four independent motors, one of which controls each of the wheels. In some embodiments, processing circuitry can monitor the wheel speed of each of the vehicle's multiple wheels by monitoring signals from sensors coupled to the motor shafts of the respective electric motors. In some embodiments, each sensor may indicate the amount of rotation of the corresponding motor shaft coupled to each of the vehicle's multiple wheels. In some embodiments, the processing circuitry may calculate the speed of each wheel based on the corresponding signals in response to the monitored wheel speed. In some embodiments, the processing circuitry may calculate the wheel speed based on sensors coupled to the wheels.

[0010] In some implementations, the processing circuitry can also determine that the wheel speed of one of the vehicle's multiple wheels exceeds a target wheel speed. Based on this determination, the processing circuitry can provide torque in the opposite direction to reduce the wheel speed as it spins. For example, when a vehicle is traveling uphill and one of the tires on the wheel suddenly loses traction and spins outward in the forward direction, the processing circuitry can reduce the torque applied to the corresponding motor to decrease the wheel speed. In some implementations, the processing circuitry can provide torque in the opposite direction (i.e., in this example, in the backward direction) to rapidly slow down the wheel's spin.

[0011] In some implementations, the processing circuitry can provide varying levels of torque to each of the multiple wheels with a response time of less than 100 microseconds. In some implementations, the processing circuitry can provide varying levels of torque to each of the multiple wheels with a response time of less than 20 microseconds. For example, the response time includes the time it takes for a signal to travel from the resolver to the processing circuitry, the time it takes for the processing circuitry to process the signal, and the time it takes to adjust the control of the motor (e.g., torque). Specifically, while the motor is providing torque to the wheels, the resolver (i.e., the sensor) monitors the motor's signal to determine the wheel speed of each wheel and transmits that information to the processing circuitry.

[0012] In some implementations, the 0-100% range of accelerator pedal input corresponds to 0 mph (miles per hour) to the maximum wheel speed. In some implementations, the maximum wheel speed in speed control mode is less than 30 mph. In another implementation, the maximum wheel speed in speed control mode is adjusted based on the surface friction on which the vehicle is situated. For example, if the vehicle is on an uneven surface, the maximum wheel speed can be adjusted based on the direction the vehicle is traveling. If the vehicle is traveling downhill, the maximum wheel speed may be lower to avoid loss of control. On the other hand, if the vehicle is traveling uphill, the maximum wheel speed may be higher to overcome gravity.

[0013] In some implementations, the processing circuitry can provide torque to each of a plurality of wheels to achieve a target wheel speed by providing an open-loop forward torque to the wheels on a first side of the vehicle and an open-loop rearward torque to the wheels on a second side of the vehicle. For example, the processing circuitry can simultaneously provide forward torque to the wheels on the first side of the vehicle and rearward torque to the wheels on the second side of the vehicle (e.g., to perform vehicle yaw). In some implementations, the second side is the opposite of the first side. For example, to perform smooth vehicle yaw, the vehicle provides forward torque to the wheels on one side of the vehicle and rearward torque to the wheels on the other side of the vehicle. In some implementations, the processing circuitry can provide open-loop forward torque to both sides of the vehicle.

[0014] In some implementations, when wheel speed control is employed, the processing circuitry can also enter a vehicle yaw mode, and may also utilize various other types of modes. In some implementations, when operating in vehicle yaw mode, the processing circuitry can provide open-loop torque to multiple wheels of the vehicle. Furthermore, in some implementations, the processing circuitry can detect slippage of multiple wheels of the vehicle and, in response, can provide closed-loop torque to multiple wheels of the vehicle.

[0015] In some implementations, the vehicle automatically enters a speed control mode in response to the spin of one or more of its wheels. For example, when the vehicle is traveling on a large rock or boulder and one of its wheels becomes airborne, the processing circuitry can automatically enter a speed control mode without any user input.

[0016] In some implementations, the multiple wheels may include four wheels. In some implementations, the vehicle may include four electric motors, each configured to provide an independent and varying torque level to each wheel (e.g., a corresponding wheel out of the four wheels).

[0017] In some implementations, the processing circuitry may enter a speed control mode after performing multiple standard checks (e.g., wheel alignment, driving mode, vehicle speed, perimeter checks, geofencing, vehicle health, etc.). For example, the processing circuitry may determine that the vehicle is stationary (or nearly stationary), where all wheels are straight relative to the vehicle's vertical axis (e.g., a vertical axis passing through the vehicle's center of gravity and perpendicular to one or more ground surfaces). In some implementations, the speed control mode may be activated only when all the vehicle's wheels are straight (e.g., aligned parallel to the vehicle's length). In some implementations, the speed control mode may be activated when the vehicle's front wheels are below a rotation threshold (e.g., less than 10 degrees from the length aligned parallel to the vehicle). In some implementations, the speed control mode may be automatically activated by the vehicle without one or more user inputs. In another implementation, the speed control mode may be activated using a button, a lever, paddle shifters, or via a voice command using voice control or any other method or combination thereof. In some implementations, the processing circuitry may initiate the speed control mode when the standard checks are met. In some implementations, input for entering the speed control mode may be received via a graphical user interface on the vehicle's display. In some implementations, input can be received via a button. In some implementations, the speed control mode can be activated based on varying surface friction at the wheels. For example, the front wheels of the vehicle can be positioned on a low-friction surface, and the rear wheels can be positioned on a high-friction surface. The surface friction can be determined based on the amount of torque applied to each wheel to cause the wheel to break the traction between the wheel and the ground. In some implementations, the speed control mode can be activated while the vehicle is moving.

[0018] In some implementations, the processing circuitry can be configured to disengage from speed control mode. For example, the processing circuitry can determine that an obstacle may be present or that any other criterion is not met. In some implementations, the processing circuitry can automatically disengage from speed control mode upon making such a determination. In some implementations, the processing circuitry can disengage from speed control mode in response to receiving user input (e.g., a key is pressed, the steering wheel is turned to a position exceeding a threshold, or the vehicle speed exceeds a speed threshold).

[0019] In some embodiments, the processing circuitry can compare the rotation of the first front wheel, the second rear wheel, the first rear wheel, and the second front wheel with a target spin rate (e.g., a spin rate of 4 revolutions per second or any other spin rate). The target spin rate can be related to a target wheel speed, and vice versa. For example, the processing circuitry can control the rotation of each of the four wheels based on a corresponding comparison with the target spin rate. In some embodiments, the processing circuitry can provide torque in opposite directions as the wheels spin. In some embodiments, the processing circuitry can apply a brake to one or more of the first and second wheels. In some embodiments, the processing circuitry can reduce the forward torque for one or more of the first wheels or the rearward torque for the second wheels. In some embodiments, the torque provided to all wheels is in the same direction.

[0020] According to another embodiment, a vehicle configured to perform wheel speed control is provided. In some embodiments, the vehicle may include multiple wheels. In some embodiments, the multiple wheels may include four wheels. In some embodiments, the four wheels may include two front wheels and two rear wheels, and each of the front and rear wheels may be configured with a motor to provide torque to each corresponding wheel. In some embodiments, the motor configured to provide torque may be an electric motor.

[0021] In some implementations, each wheel may be configured with a motor, including a first motor configured to transmit torque to the outward front wheel, a second motor configured to transmit torque to the inward front wheel, a third motor configured to transmit torque to the outward rear wheel, and a fourth motor configured to transmit torque to the inward rear wheel.

[0022] In some embodiments, a non-transitory computer-readable medium is provided, on which instructions for performing speed control of the vehicle's wheels are encoded. In some embodiments, the encoded instructions can be executed by processing circuitry of a vehicle having front and rear wheels. Attached Figure Description

[0023] The present disclosure is described in detail with reference to the following accompanying drawings, which illustrate one or more various embodiments. The drawings are provided for illustrative purposes only and show only typical or exemplary embodiments. These drawings are provided to facilitate understanding of the concepts disclosed herein and should not be considered as limitations on the breadth, scope, or applicability of these concepts. It should be noted that these drawings are not necessarily drawn to scale for clarity and ease of illustration.

[0024] Figure 1 A top sectional view of an exemplary vehicle according to some embodiments of the present disclosure is shown;

[0025] Figure 2 A side view of an exemplary vehicle located on an inclined surface with varying surface frictional forces, according to some embodiments of the present disclosure, is shown.

[0026] Figure 3 A side view of an exemplary vehicle with varying surface friction according to some embodiments of the present disclosure is shown;

[0027] Figure 4 This is a detailed view of a dual electric motor shaft according to some embodiments of this disclosure;

[0028] Figure 5 A flowchart depicts an exemplary process for controlling the wheel speed of a vehicle according to some embodiments of this disclosure;

[0029] Figure 6 The diagram shows examples of accelerator pedal input and target wheel speed for a speed control mode according to some embodiments of this disclosure; and

[0030] Figure 7 A system diagram is depicted illustrating an exemplary system including processing circuitry, input variables, sensors, and output variables according to some embodiments of the present disclosure. Detailed Implementation

[0031] This disclosure relates to operating a vehicle in a speed control mode. In a speed control mode, the vehicle's wheels operate at a target wheel speed to better control the vehicle on uneven and varying friction surfaces when using two or more motors. In some embodiments, the vehicle includes a normal turning mode and a vehicle yaw mode, in which the vehicle yaws by changing the position of the front wheels relative to the vertical axis (e.g., each relative to...). Figure 1The vehicle yaws at a corresponding vertical angle of 170°, and in this yaw mode, the electric vehicle rotates about a point under the vehicle chassis, allowing the vehicle to pivot in a circle with zero or minimum turning radius. Each of these modes can benefit from additional control of each wheel to improve operation. In some embodiments, the vehicle is configured to operate one or more of these modes simultaneously. The vehicle yaw mode allows the vehicle to pivot about a point under the vehicle chassis. However, it should be noted that one or more vehicles can pivot under the chassis without the one or more operating modes described herein. In some cases, the vehicle can perform one or more pivots without selecting or entering any mode. However, for the purpose of illustration and description without limiting this disclosure, vehicle capabilities described as pivoting about a point, rotating with a reduced or minimum turning radius, initiating forward torque to one or more wheels while initiating rearward torque to one or more other wheels, and other examples, can be performed in normal driving mode, vehicle yaw mode, speed control mode, while operating in closed-loop mode, open-loop mode, and / or combinations of these modes, as well as other vehicle modes. However, these vehicles can perform these operations simultaneously, sequentially, and / or in any combination of them in multiple modes.

[0032] In some embodiments, this disclosure employs a control system 701 that receives input variables 702-706 and transmits output variables 726-732, see reference. Figure 7 The control system 701 includes a communication interface 707, processing circuitry 722, sensors 712-720, and a motor and brake controller 724. The exemplary processing circuitry 722 includes a processor 708 and a memory 710. In this exemplary example, the control system 701 can be used to control the speed of a vehicle's wheels (e.g., to provide better control on uneven, variable, and surfaces with varying friction when using two or more motors). The system and its components will be described in more detail below.

[0033] In some implementation schemes, reference Figure 1The torque of each wheel 102, 104, 106, 108 of vehicle 100 can be independently controlled. In some embodiments, the torque of each wheel of the vehicle can be provided proportionally to the accelerator pedal input (e.g., the degree to which the user has pressed the accelerator pedal 113, the accelerator pedal is pressed to its maximum extent, the accelerator pedal is pressed to the bottom plate, and other possibilities contemplated herein) and the surface friction at each wheel 102, 104, 106, 108. In some embodiments, vehicle 100 can be configured to operate in speed control mode when certain conditions are met (e.g., when the vehicle speed is sufficiently low and / or the current wheels are aligned parallel to the vehicle's direction). In some embodiments, vehicle 100 is configured to receive input from the user via a graphical user interface to enter speed control mode. In some embodiments, the vehicle is configured to receive additional input, such as the type of road (e.g., road surface, sand, ice, wet, gravel) and the maximum wheel speed when operating in speed control mode. For example, the maximum wheel speed for each wheel can be set to 30 mph, 20 mph, 10 mph, or any value listed in a lookup table for the type of surface the vehicle is on. In some embodiments, the system receives accelerator pedal input when operating in speed control mode. In some embodiments, the vehicle's processing circuitry 722 determines the target wheel speeds of the vehicle's wheels based on the accelerator pedal input. For example, the target wheel speed for each wheel could be 30 mph, 20 mph, or 10 mph. In some embodiments, the processing circuitry can monitor the wheel speed of each wheel. In some embodiments, the processing circuitry can determine a difference between the monitored wheel speed and the target wheel speed. In some embodiments, the processing circuitry can provide torque to each of the multiple wheels to modify the monitored wheel speed based on the corresponding difference.

[0034] As mentioned herein, the term "speed control mode" refers to any kind of mode that is automatically triggered / entered without user input, or a technique for operating a vehicle such that the torque supplied to each of the wheels achieves a target wheel speed determined based on the accelerator pedal input. In some embodiments, the target wheel speed may be proportional to the accelerator pedal input. For example, when the maximum wheel speed is 30 mph, 50% of the accelerator pedal input corresponds to a target wheel speed of 15 mph. In some embodiments, the maximum wheel speed in the speed control mode can be adjusted. Based on pressing 50% of the accelerator pedal, each wheel receives torque to achieve a target wheel speed of 15 mph. For example, a wheel on a slippery surface (e.g., wet surface, icy surface) can achieve 15 mph with a very small amount of torque applied. On the other hand, a wheel on a higher friction surface (e.g., gravel surface, pavement) may require a higher torque to achieve 15 mph. In another embodiment, the target wheel speed may be based on different user inputs. For example, a user may input the target wheel speed using a button, lever, paddle shifters, or via voice commands using voice control or any other method or combination thereof.

[0035] As mentioned herein, the term "vehicle yaw mode" refers to any type of mode, i.e., a mode that is automatically triggered without user input, or a technique used to operate a vehicle such that the outer and inner wheels of the vehicle are provided with torque in opposite directions. The term "outer" refers to a wheel on one side of the vehicle that is provided with forward torque, and the term "inner" refers to a wheel on the side of the vehicle that is provided with rearward torque. Therefore, which wheels of the vehicle are considered outer and inner wheels will depend on the yaw direction. In some embodiments, the vehicle yaw mode includes independent torque control for each wheel, which is related to the wheel speed at each wheel. For example, the outer wheels of the vehicle operate with forward torque, and the inner wheels of the vehicle operate with rearward torque. In some embodiments, as the vehicle moves between surfaces with varying friction, the processing circuitry 722 adjusts the torque for each wheel based on the monitored wheel speed and the target wheel speed. In some embodiments, the vehicle yaw mode includes independently controlling each wheel to induce yaw of the vehicle. For example, the outer front wheels of the vehicle operate with a first forward torque, the outer rear wheels operate with a second forward torque, the inner front wheels operate with a first rearward torque, and the inner rear wheels operate with a second rearward torque. In some embodiments, the inner wheels are referred to as the first side, and the outer wheels as the second side.

[0036] Figure 1A top-down sectional view of an exemplary vehicle 100 according to some embodiments of the present disclosure is shown. In some embodiments, vehicle 100 may be a two-door sedan, a four-door sedan, a truck, a sports utility vehicle, a van, a bus, or any other type of vehicle.

[0037] In some embodiments, vehicle 100 may include a left front wheel 102, a right front wheel 104, a left rear wheel 106, and a right rear wheel 108. In some embodiments, vehicle 100 may include a motor 112. Motor 112 may be connected to the left front wheel 102 (e.g., via a belt, chain, gear, or any other connecting device). Vehicle 100 may also include motors 114, 116, and 118, respectively, which are similarly connected to wheels 104, 106, and 108. In some embodiments, motors 112, 114, 116, and 118 may be configured to provide forward or rearward torque to their respective wheels 102, 104, 106, and 108. In some embodiments, vehicle 100 may include an accelerator pedal 113 configured to provide an accelerator pedal input to a vehicle dynamics controller 111, which is configured to convert the accelerator pedal input into a target wheel speed. In some embodiments, vehicle 100 may include a resolver 142 attached to motor 112 and configured to monitor and transmit signals from resolver 142 to vehicle dynamics controller 111. Furthermore, vehicle dynamics controller 111 communicates with each resolver 142, 144, 146, 148, which is connected to each motor (112, 114, 116, 118) via a corresponding communication line (132, 134, 136, 138).

[0038] In some embodiments, motors 112, 114, 116, and 118 can be any type of motor capable of generating power (e.g., throttle motor, hybrid motor, electric motor, battery-powered electric motor, hydrogen fuel cell motor). In some embodiments, motors 112, 114, 116, and 118 can be configured to drive or propel a vehicle by using multiple battery cells packaged together to form one or more battery modules or components to store energy and release energy on demand. In some embodiments, motors 112, 114, 116, and 118 can be devices connected to a main single motor (not shown) and configured to independently transmit power from the single motor to wheels 102, 104, 106, and 108. For example, motors 112, 114, 116, and 118 can independently transmit power to wheels 102, 104, 106, and 108, causing wheels 104 and 108 to spin in one direction (e.g., forward) and wheels 102 and 106 to spin in the opposite direction (e.g., backward), thereby enabling vehicle 100 to achieve a zero-degree turning radius (i.e., vehicle yaw via a vehicle yaw mode). In some embodiments, the vehicle yaw mode includes independently controlling each wheel to induce yaw of the vehicle. For example, in vehicle yaw mode, motors 112 and 116 can be configured to provide forward torque to their wheels 102 and 106, respectively, and motors 114 and 118 can be configured to provide rearward torque to their wheels 104 and 108. In some implementations, wheels 104 and 108 may spin at 500 rpm in one direction / clockwise (e.g., forward), and wheels 102 and 106 may spin in the opposite direction / counterclockwise (e.g., backward), thereby enabling vehicle 100 to perform smooth rotation.

[0039] In some embodiments, vehicle 100 may include processing circuitry 722. In some embodiments, the processing circuitry may include an onboard vehicle computer capable of controlling multiple features or capabilities of the vehicle. In some embodiments, the processing circuitry may be communicatively connected to user inputs of vehicle 100 (e.g., a graphical user interface), vehicle sensors, and transient or non-transitory memory (e.g., memory storing instructions for operating the vehicle).

[0040] In some embodiments, vehicle 100 may include multiple sensors. For example, some of the multiple sensors may include sensors for determining the speed of vehicle 100, the degree of rotation of the front wheels 102, 104 of vehicle 100, a vehicle rotation sensor for determining the rotation of the vehicle in vehicle yaw mode, wheel rotation sensors (e.g., resolvers 142, 144, 146, 148) for determining the wheel speed of each of the wheels 102, 104, 106, and 108 of vehicle 100, and an accelerometer sensor.

[0041] In some implementations, the processing circuitry of vehicle 100 may be able to directly control features of vehicle 100 with or without user input. In one example, the processing circuitry may be able to actuate motor 112 to provide a specified amount of rearward or forward torque to the left front wheel 102 to achieve a target wheel speed. Similarly, the processing circuitry may be able to actuate any of motors 114, 116, and 118 to provide a specified amount of rearward or forward torque to wheels 104, 106, and 108, respectively, to achieve a target wheel speed.

[0042] In some embodiments, the left front wheel 102 and the right front wheel 104 may be connected via a drive shaft (not shown). Figure 1 As shown, the vehicle is positioned such that each wheel is located on a different surface with varying surface friction. For example, surface 120 is located under the left front wheel 102, surface 122 is located under the right front wheel 104, surface 124 is located under the left rear wheel 106, and surface 126 is located under the right rear wheel 108. As illustrated, surfaces 120, 122, 124, and 126 can be varied and / or different surface surfaces, including but not limited to road surfaces with or without gravel, rock, boulder, rainwater, and snow, as well as other possibilities envisioned herein. Figure 1 A vehicle 100 is depicted performing vehicle yaw, wherein left wheels 102 and 106 receive rearward torque and right wheels 104 and 108 receive forward torque. However, those skilled in the art will recognize that similar techniques can be used to perform any rotation or motion, including when all wheels receive torque in the same direction.

[0043] In some implementations, when yawing to the left, vehicle 100 can provide a rearward torque (Ti) to the left wheels (e.g., the left front wheel 102 and the left rear wheel 106) based on friction on the ground. R1 and T R2 To achieve the target wheel speed. In some implementations, the vehicle can provide a forward torque (T0) to the right wheels (e.g., the right front wheel 104 and the right rear wheel 108) based on friction on the ground. F1 and T F2To achieve a target wheel speed (e.g., a target wheel speed proportional to the accelerator pedal input). For example, vehicle 100 can provide a forward torque T to the right front wheel 104. F1 It can also provide forward torque T to the right rear wheel 108. F2 In some implementations, vehicle 100 may provide a rearward torque (Ti) to the left wheel (e.g., the left front wheel 102 and the left rear wheel 106) based on friction on the ground. R1 and T R2 This is to achieve a target wheel speed (i.e., a target wheel speed proportional to the accelerator pedal input). For example, vehicle 100 can provide a rearward torque T to the left front wheel 102. R1 It can also provide rearward torque T to the left rear wheel 106. R2 Forward torque T F1 and T F2 Rear torque T R1 and T R2 Each of these is an independent torque and a function of the corresponding wheel speed. For example, the right front wheel 104 is located on a high-friction surface 122 (e.g., road surface, gravel), and therefore requires a greater torque T than the right rear wheel 108 located on a low-friction surface 126 (e.g., icy road, sand, wet road). F2 Higher torque T F1 .

[0044] In some embodiments, on a relatively uniform ground surface, the torque applied to each wheel 102, 104, 106, and 108 to achieve a target wheel speed should be substantially similar, substantially the same, substantially identical, and other possibilities contemplated herein. In another embodiment, on a relatively uniform ground surface, vehicle 100 may take into account the load in vehicle 100 when providing torque to wheels 102, 104, 106, and 108. For example, if vehicle 100 carries heavy material in the rear of vehicle 100, the torque applied to each wheel 102, 104, 106, and 108 to achieve a target wheel speed will vary based on the load. In some embodiments, sensors 712-721 on the vehicle 100 suspension may transmit signals to vehicle dynamics control regarding the weight at each wheel. Based on the weight at each wheel 102, 104, 106, and 108, processing circuitry 722 may adjust the torque used for each wheel 102, 104, 106, and 108 to achieve the target wheel speed. Specifically, the torque used for the rear wheels 106 and 108 can be higher to overcome the additional payload.

[0045] In some implementations, the speed control mode can be used in any vehicle 100 capable of distributing torque (which may include braking) and monitoring the wheel speeds of each wheel 102, 104, 106, and 108. For example, vehicle 100 may provide independent torque distribution to the right wheels 104 and 108 and the left wheels 102 and 106. According to another example, vehicle 100 may provide independent torque and braking distribution to the left wheels 102 and 106 and the right wheels 104 and 108. According to yet another example, vehicle 100 may provide independent torque and braking distribution to the left front wheel 102, the left rear wheel 106, the right front wheel 104, and the right rear wheel 108. The foregoing allows the driver to precisely control the center of rotation (e.g., zero-radius rotation) while also smoothly executing rotation.

[0046] The foregoing Figure 1 The principles of this disclosure are merely illustrative, and various modifications can be made by those skilled in the art without departing from the scope of this disclosure. The above embodiments are presented for illustrative purposes and not for limitation. For example, any combination of motors 112, 114, 116, and 118 and a powertrain can be used in vehicle 100 according to this disclosure. In some examples, Figure 1 The rear motors 116 and 118 can be used in combination with a single front motor 112. According to this configuration, the vehicle 100 includes three motors (one front motor and two rear motors). In another example, the single rear motor 116 can be combined with... Figure 1 The two front motors 112 and 114 are used in combination. According to this configuration, the vehicle 100 includes three motors (two front motors and one rear motor).

[0047] In some embodiments, a method for controlling vehicle 100 may include determining a target wheel speed for each of one or more wheels of vehicle 100. In some embodiments, vehicle 100 has two, three, or four wheels. Based on the number of wheels the vehicle 100 has, the method determines the target wheel speed for each wheel based on accelerator pedal input. For example, processing circuitry 722 detects the actual wheel speed of each of one or more wheels 102, 104, 106, 108, each controlled by one or more independent motors 112, 114, 116, 118. In some embodiments, the processing circuitry may determine one or more target torques for each of the one or more wheels based at least on the actual wheel speed and the target wheel speed for each of the wheels. In this example, each target wheel speed is configured with a target torque. The target torques can be adjusted by one or more independent motors 112, 114, 116, 118 to achieve one or more target torques.

[0048] Figure 2 A side view of an exemplary vehicle 200 located on an uneven surface 203 (e.g., an inclined surface, a downslope, a ramp, or a combination thereof) with varying surface frictional forces, according to some embodiments of the present disclosure, is shown. In some embodiments, vehicle 200 may be a two-door sedan, a four-door sedan, a truck, a sports utility vehicle, a van, a full-size van, a minivan, a bus, or any other type of vehicle.

[0049] In some embodiments, the processing circuit 722 may also monitor vehicle tilt based on a tilt sensor. For example, the vehicle may be in a tilted position, a slope position, or a combination thereof. In some embodiments, a tilted position includes the front wheels of the vehicle being higher than the rear wheels, or the rear wheels being higher than the front wheels. For example, the vehicle is on a hill, where the front of the vehicle is higher than the rear. Alternatively, the vehicle may be tilted, where the rear of the vehicle is higher than the front. In some embodiments, a slope position includes the outer wheels (e.g., a first side) of the vehicle being higher than the inner wheels (e.g., a second side), or the inner wheels (e.g., a second side) being higher than the outer wheels (e.g., a first side). For example, the vehicle is on a hillside, where the inner side of the vehicle is higher than the outer side. Alternatively, the outer side of the vehicle is higher than the inner side. In some embodiments, the processing circuit may compare the vehicle tilt to a vehicle tilt threshold (e.g., 10% tilt, 8% tilt, etc.). In response to determining that the vehicle tilt is below the vehicle tilt threshold, the processing circuit may activate a vehicle yaw mode or a speed control mode.

[0050] In some embodiments, vehicle 200 may include a left front wheel 208, a right front wheel (not shown), a left rear wheel 206, and a right rear wheel (not shown). In some embodiments, the vehicle may be positioned on an uneven surface 203. In some embodiments, the vehicle may be positioned on an uneven surface 203 having surfaces (202 and 204) with different frictional forces on the ground. In some embodiments, the different frictional surfaces may include a lower frictional surface 202 and a higher frictional surface 204. In some embodiments, based on the different frictional surfaces (202 and 204) and the uneven surface 203 on which the vehicle is positioned, the vehicle may provide individual torque to each of the wheels (206 and 208), as well as the right rear wheel (not shown) and the right front wheel (not shown), to enable the wheels to achieve a target wheel speed. For example, when the vehicle is positioned on an uneven surface 203 (e.g., an inclined surface), the torque 212 applied to each of the left front wheel 208 and the right front wheel (not shown) is lower than the torque 210 applied to the left rear wheel 206 and the right rear wheel (not shown), taking into account the inclined surface. Specifically, because the front of the vehicle is raised due to the uneven surface 203 (e.g., an inclined surface), the weight of the vehicle is redistributed over wheels 206 and 208, with more weight placed on the left rear wheel 206 and the right rear wheel (not shown) due to the inclined surface. In some embodiments, the torque applied to each of the rear wheel 206 and the right rear wheel (not shown) is greater than the torque applied to the front wheel 208 and the right front wheel (not shown) due to the uneven surface 203 (e.g., an inclined surface). For illustrative purposes, the size of arrows 210 and 212 indicates the amount of torque applied (i.e., a larger arrow indicates a higher torque, and a smaller arrow indicates a lower torque).

[0051] Figure 3 A side view of an exemplary vehicle 300 with varying surface friction according to some embodiments of the present disclosure is shown. In some embodiments, vehicle 300 may be a two-door sedan, a four-door sedan, a truck, a sports utility vehicle, a van, a bus, or any other type of vehicle, such as those described above. Figure 1 The vehicle 100 described above and the above-mentioned vehicle 100 Figure 2 The vehicle described is 200.

[0052] In some embodiments, vehicle 300 may include a left front wheel 308, a right front wheel (not shown), a left rear wheel 306, and a right rear wheel (not shown). In some embodiments, vehicle 300 is situated on a flat surface 303 (e.g., flat or substantially flat, essentially flat) that has different frictional surfaces on the ground. In some embodiments, the different frictional surfaces include a lower frictional surface 302 and a higher frictional surface 304. In some embodiments, based on the different frictional surfaces 302 and 304 on the ground, vehicle 300 may provide torques 310 and 312 to each of the wheels (i.e., the left front wheel 308, the right front wheel (not shown), the left rear wheel 306, and the right rear wheel (not shown)) to enable the wheels to achieve a target wheel speed. In some embodiments, vehicle 300 may provide independent torque to each of the wheels 306 and 308 on vehicle 300. For example, when vehicle 300 is positioned on a flat surface 303 with different surface frictions 302 and 304, the torques 310 and 312 applied to each of the left front wheel 308, right front wheel (not shown), left rear wheel 306, and right rear wheel (not shown) are proportional to the friction surfaces. Specifically, when the friction under each wheel 306, 308 increases (e.g., a wheel moves from a wet surface to a dry surface), the amount of torque required for wheels 306, 308 to maintain a target wheel speed may increase. Similarly, when the friction under each wheel 306, 308 decreases (e.g., a wheel moves from a wet surface to ice), the amount of torque required for wheels 306, 308 to maintain a target wheel speed may decrease. In some embodiments, when the wheel speed of wheel 308 is higher than the target wheel speed, vehicle 300 may apply braking to wheel 308 or provide torque in the opposite direction, or may reduce the power used for wheel 308, and other possibilities envisioned herein exist. Similarly, when the wheel speed of wheel 306 is higher than the target wheel speed, vehicle 300 may apply braking to wheel 306 or provide torque in the opposite direction, or may reduce the power used for the wheel, as well as other possibilities envisioned herein. In some embodiments, due to the different friction surfaces 302 and 304, the torque applied to the left rear wheel 306 may be less than the torque applied to the left front wheel 308. For illustrative purposes, the size of arrows 310 and 312 indicates the amount of torque applied (i.e., the larger arrow 312 indicates a higher torque, and the smaller arrow 310 indicates a lower torque).

[0053] Figure 4This is a detailed view of a dual electric motor shaft 400 according to some embodiments of the present disclosure. The dual electric motor shaft 400 shown can be positioned in the front of one or more vehicles 100, 200, and / or 300 and providing torque to the front wheels 102 and 104; it can be positioned in the rear of one or more vehicles 100, 200, and / or 300 and providing torque to the rear wheels 106 and 108; or the dual electric motor shaft 400 can be positioned in both the front and rear of one or more vehicles 100, 200, and / or 300 and providing torque to both the front wheels 102 and 104 and the rear wheels 106 and 108. The dual electric motor shaft 400 includes two electric motors 402 and 404, gearboxes 401 and 403, shafts 405 and 407, and resolvers 406 and 408. For example, in one configuration, with the dual electric motor shaft 400 positioned in the front of the vehicle 100, the electric motor 402 can be coupled to the gearbox 401 and drive the left front wheel 102 via the shaft 407. Figure 1 The rotary transformer 408 monitors wheel speed. However, this is just an example, and a single electric motor can drive multiple wheels.

[0054] Figure 5 A flowchart depicts an exemplary process for controlling the wheel speed of a vehicle according to some embodiments of this disclosure.

[0055] In some implementations, process 500 may be handled by processing circuitry 722 of system 700. Figure 7 ) to be executed. It should be noted that process 500 or any of its steps can be performed. Figure 7 It is executed on the system or provided by the system.

[0056] Process 500 begins at step 502, where the processing circuitry can receive input to enter speed control mode. For example, the processing circuitry can enter speed control mode after the user issues a command requesting this mode (e.g., by pressing an appropriate button, shift paddle, input via a graphical user interface, or any other input). However, referencing... Figures 1 to 4One or more vehicles 100, 200, and / or 300 can automatically enter a speed control mode based on sensor readings described herein without any user input. Processing circuitry can determine whether one or more speed control mode initialization criteria are met. For example, whether the amount of rotation of the front wheels 102 and 104 of vehicle 100 is met. In some embodiments, the processing circuitry can use sensors connected to the steering column to determine the rotation angles of wheels 102 and 104. In another example, obstacle avoidance sensors can detect any obstacles around vehicle 100 or in the vehicle's path. In some embodiments, the processing circuitry can enter a speed control mode after determining, based on sensors in vehicle 100, that vehicle 100 is located on an uneven surface 203 (e.g., climbing rocks, an incline, or a downhill slope). For example, when vehicle 200 is climbing rocks and one of the wheels 208 becomes airborne, the speed control mode can control the speed of wheel rotation.

[0057] In some implementations, the processing circuitry can (e.g., based on pressure sensors or calculated surface friction) determine the clearance between one or more of the multiple wheels and one or more ground surfaces. For example, when vehicle 100 traverses uneven surface 203, the left front wheel 208 ( Figure 2 The vehicle becomes airborne, with a gap between the left front wheel 208 and the uneven ground 203. In some embodiments, in response to determining the gap between the left front wheel 208 and the uneven ground 203, the processing circuit automatically enters a speed control mode without any user input.

[0058] Process 500 continues at 504, where processing circuitry 722 may proceed based on the result of step 502. For example, if the multiple entry criteria are met, the processing circuitry may proceed to step 504. At 504, the processing circuitry may receive accelerator pedal input from accelerator pedal 113. For example, the user may have pressed the accelerator pedal input up to 50%. The user may press the accelerator pedal input from "0" (i.e., no accelerator pedal input) to 100% (i.e., pedal to the bottom). In some embodiments, the accelerator pedal input may be pre-programmed and automatically provided with preset pedal inputs for each motor in the motor.

[0059] In some implementations, step 504 initiates ramp torque in open-loop mode (i.e., without adjusting torque based on monitoring any sensor data). For example, in open-loop mode, the torque applied to each wheel ramps regardless of the accelerator pedal input. (Revisit) Figure 1For example, consider one or more motors 112, 114, 116, and 118 configured to provide and / or generate torque to one or more of wheels 102, 104, 106, and 108, respectively. In this example, motors 114 and 118 may generate open-loop forward torque to wheels 104 and 108, respectively. Furthermore, motors 112 and 116 may generate open-loop rearward torque to wheels 102 and 106, respectively. In some embodiments, the left side of the vehicle, including the left front wheel 102 and the left rear wheel 106, is a first side 150 of vehicle 100, and the right side of vehicle 100, including the right front wheel 104 and the right rear wheel 108, is a second side 160 of vehicle 100. In some embodiments, the processing circuitry can provide torque to each of a plurality of wheels by providing open-loop forward torque to wheels 102 and 106 on a first side 150 of vehicle 100 and open-loop rearward torque to wheels 104 and 108 on a second side 160 of vehicle 100 to achieve a target wheel speed. For example, the processing circuitry can simultaneously provide forward torque to wheels 102 and 106 on the first side 150 of vehicle 100 and rearward torque to wheels 104 and 108 on the second side 160 of vehicle 100 (e.g., to perform vehicle yaw). In some embodiments, the second side 160 is opposite to the first side 150. For example, to perform smooth vehicle yaw, vehicle 100 provides forward torque to wheels 102 and 106 on the first side 150 of vehicle 100 and rearward torque to wheels 104 and 108 on the second side 160 of vehicle 100.

[0060] In some embodiments, processing circuitry 722 can provide open-loop torque to each of the multiple wheels to achieve wheel slippage. For example, this is achieved by providing open-loop rearward torque to wheels 104 and 108 on the second side 160 of vehicle 100, and open-loop forward torque to wheels 102 and 106 on the first side 150 of vehicle 100. During wheel slippage, the processing circuitry can enter a closed-loop mode where it monitors wheel speeds. The torque is increased or decreased until the monitored wheel speed corresponds to a target wheel speed. In some embodiments, step 504 initiates ramping torque in closed-loop mode, where the amount of torque provided to the wheels is based on the amount of accelerator pedal input. For example, in closed-loop mode, the torque applied to each wheel is based on sensors monitoring vehicle outputs (e.g., wheel speeds), regardless of accelerator pedal input. For example, consider one or more motors 112, 114, 116, and 118 configured to provide and / or generate torque to one or more of wheels 102, 104, 106, and 108, respectively, based on the monitored wheel speed at each wheel. In this example, motors 114 and 118 could generate open-loop forward torque to wheels 104 and 108, respectively. Furthermore, motors 112 and 116 could generate closed-loop rearward torque to wheels 102 and 106, respectively. For example, the torque amount could be proportional to the amount of accelerator pedal pressure, or it could be determined using a lookup table. In another example, the torque amount could be based on the difference between the monitored wheel speed and the target wheel speed.

[0061] Process 500 continues at 506, where the processing circuitry may proceed based on the result of step 504. For example, if accelerator pedal input is received, the processing circuitry may proceed to step 506. At 506, the processing circuitry may determine a target wheel speed based on the accelerator pedal input. For example, in response to receiving accelerator pedal input, the processing circuitry determines the target wheel speed based on the degree to which the user has pressed the accelerator pedal. In one embodiment, the target wheel speed is proportional to the degree to which the user has pressed the accelerator pedal. For example, 25% of the accelerator pedal input is proportional to 25% of the maximum target speed. The range in which the wheel can spin can be adjusted. In some embodiments, this range is set to speeds from 0 mph to 30 mph, where the maximum target speed is 30 mph. In this example, 25% of the accelerator pedal input is proportional to 7.5 mph. In another example, 50% of the accelerator pedal input is proportional to 15 mph. In another embodiment, the target wheel speed is a command issued by the user requesting such a target wheel speed (e.g., by pressing an appropriate button, paddle shifter, input via a graphical user interface, or any other input). In one aspect of this implementation, the target wheel speed can be adjusted using appropriate buttons, paddle shifters, or input via a graphical user interface. In this configuration, the amount of time the user presses the accelerator pedal is independent of the wheel speed.

[0062] At point 508, the processing circuitry monitors the wheel speed of each of the vehicle's multiple wheels. In some embodiments, the wheel speed is determined by one or more vehicle sensors (e.g., resolvers) configured to measure the rotation of the vehicle's motor (e.g., at the motor shaft). The vehicle's sensors monitor sensor signals from the motor to determine the wheel speed of each wheel and transmit that information to the control circuitry. In another embodiment, the wheel speed is determined by one or more vehicle sensors (e.g., sensors coupled to the axle) configured to measure the actual wheel speed. In some embodiments, the control circuitry is communicatively connected to one or more sensors that provide data indicating the wheel speed of each wheel of the vehicle. For example, Figure 7 The sensor 712 can provide data indicating the wheel speed of each wheel 102, 104, 106, 108 of the vehicle 100.

[0063] In some embodiments, process 500 continues at 510, where processing circuitry 722 may determine a difference for each wheel based on the monitored wheel speed and the target wheel speed. In some embodiments, the processing circuitry may determine that the monitored wheel speed is less than the target wheel speed, that the monitored wheel speed is approximately equal to the target wheel speed, or that the monitored wheel speed is greater than the target wheel speed. In some embodiments, process 500 continues at 512, where the processing circuitry executes a decision tree. Specifically, based on the monitored wheel speed (M) and the target wheel speed (T), the processing circuitry determines whether there is a difference and provides torque to each wheel based on the corresponding difference.

[0064] In some embodiments, if the difference is zero ("0") (i.e., M = T) or if the difference is within a small number (e.g., ±1 mph), then process 500 continues at 516 by: maintaining the torque applied to each wheel and returning to step 504 to receive the current accelerator pedal input from the user. For example, as the operator of the vehicle adjusts the pedal position, the accelerator pedal input may change over time.

[0065] In some embodiments, if the monitored wheel speed (M) at 512 is less than the target wheel speed (T) of the wheel (i.e., M < T), then process 500 continues at 514 to provide increased torque to the wheel based on the difference to achieve the target wheel speed. In some embodiments, processing circuitry 722 may actuate any one of motors 112, 114, 116, and 118 to provide increased torque to the corresponding wheel 102, 104, 106, or 108.

[0066] In some embodiments, if the monitored wheel speed (M) at 512 is greater than the target wheel speed (T) of the wheel (i.e., M > T), then process 500 continues at 518 to provide reduced or opposing torque to the wheel based on the difference to achieve the target wheel speed. In some embodiments, processing circuitry 722 may actuate any one of motors 112, 114, 116, and 118 to provide reduced or opposing (i.e., in the direction opposite to the monitored wheel speed) torque to any one of wheels 102, 104, 106, and 108. In some embodiments, the processing circuitry applies a mechanical brake to provide opposing torque to a wheel that exceeds (e.g., significantly exceeds) the target wheel speed.

[0067] In some implementations, applying torque to each of a plurality of wheels to achieve the target wheel speed based on a corresponding difference (whether the difference is greater than or less than the target wheel speed) can be performed by a proportional-integral-derivative (PID) controller. In some implementations, the processing circuitry implements the PID controller and can continuously calculate the corresponding difference between the monitored wheel speed (M) and the target wheel speed (T), and apply torque based on proportional, integral, and derivative terms (denoted as P, I, and D, respectively). For example, as long as a small difference is observed between the monitored wheel speed and the target wheel speed, the change in the applied torque is proportionally small.

[0068] In some implementations, the torque applied to each of the multiple wheels based on a corresponding difference may be based on a threshold. In some implementations, processing circuitry 722 may determine a difference between the monitored wheel speed (M) and the target wheel speed (T) that is greater than a first threshold (e.g., ±5 mph of the target wheel speed), and in response, may provide a first torque (e.g., 50% of the torque) to each wheel based on the difference to achieve the target speed. In some implementations, processing circuitry may determine a difference that is greater than a second threshold (e.g., ±10 mph of the target wheel speed). In response, processing circuitry may provide a second torque (e.g., maximum torque) to each wheel based on the difference to achieve the target speed.

[0069] It should be understood that process 500 is merely illustrative and various modifications may be made within the scope of this disclosure. For example, in some embodiments, steps 506, 508, and 510 may be omitted, and step 512 may be performed in response to the accelerator pedal being pressed.

[0070] Figure 6 The diagram shows examples of accelerator pedal input and target wheel speed for a speed control mode according to some embodiments of this disclosure. In some embodiments, Figure 6 The curve data can be obtained from Figure 5 Step 504 is used to determine the target wheel speed based on the accelerator pedal input. In some implementations, the range of the target wheel speed is adjusted based on the ground surface on which the vehicle is located. Figure 6As shown, the accelerator pedal input is proportional to the target wheel speed. While the range of the target wheel speed can be adjusted, this example shows a range of 0 mph to 30 mph. Target wheel speed 602 shows the target wheel speed (e.g., in MPH) allowed based on the accelerator pedal input, expressed as a percentage along the x-axis of the graph. For example, when the accelerator pedal input increases to 50%, the target wheel speed increases to 15 mph, and the processing circuitry can adjust the torque for each wheel and / or apply braking to achieve target wheel speed 602. Table 1, reproduced below, shows the data represented on the graph. It should be noted that Table 1 and... Figure 6 Each of these is provided for illustrative purposes and should not be construed as limiting this disclosure, as various other relationships between the target wheel speed and the accelerator pedal input can be implemented, such as other linear, nonlinear and / or exponential relationships, as well as other variations contemplated herein.

[0071]

[0072]

[0073] Table 1

[0074] Figure 7 A system diagram of an exemplary system 700 according to several embodiments of the present disclosure is depicted. This exemplary system includes a control system 701, input variables 702-706, and output variables 726-732. As shown, the control system 701 includes a communication interface 707, processing circuitry 722, sensors 712-720, and a motor and brake controller 724. The exemplary processing circuitry 722 includes a processor 708 and a memory 710. In the exemplary example, the control system 701 can be used for the speed control of the wheels of a vehicle (e.g., for better control on uneven and differently frictional surfaces when using two or more motors). In some embodiments, system 700 is integrated with... Figure 1 The speed of wheels 102, 104, 106 and 108 in vehicle 100 is controlled.

[0075] Processing circuitry 722 may include hardware, software, or both implemented on one or more modules configured to provide control of the front wheels 726 and 728 and the rear wheels 730 and 732 of a vehicle. In some embodiments, processor 708 includes one or more microprocessors, microcontrollers, digital signal processors, programmable logic devices, field-programmable gate arrays (FPGAs), application-specific integrated circuits (ASICs), or any suitable combination thereof. In some embodiments, processor 708 is distributed across more than one processor or processing unit. In some embodiments, processing circuitry 722 executes instructions stored in memory for managing a four-wheeled vehicle 100, a three-wheeled vehicle (not shown), or a two-wheeled vehicle (not shown). In some embodiments, memory 710 is an electronic storage device that is part of processing circuitry 722. For example, memory 710 may be configured to store electronic data, computer instructions, applications, firmware, or any other suitable information. In some embodiments, memory 710 includes random access memory, read-only memory, hard disk drives, optical disk drives, solid-state devices, or any other suitable memory storage devices, or any combination thereof. For example, memory may be used to initiate startup routines. Communication interface 707 may include electrical terminals, level shifters, communication modules, connectors, cables, antennas, any other suitable components for transmitting and receiving information, or any combination thereof. For example, communication interface 707 may include an Ethernet interface, a WiFi interface, an optical interface, a sensor interface (e.g., for interacting with one or more sensors 712-721), any other suitable wired or wireless interface, or any combination thereof. For illustration, communication interface 707 may include a sensor interface having a power supply, an analog-to-digital converter, a digital-to-analog converter, signal processing equipment, signal conditioning equipment, connectors, electrical terminals, any other suitable components for managing signals to and from the sensor, or any combination thereof. For further illustration, the sensor interface may be configured to communicate with a resolver 712 (e.g., a rotary encoder coupled to a motor shaft or gear shaft), a vehicle yaw sensor 714, an orientation sensor 716, a speed sensor 718, an accelerometer sensor 720 (e.g., a vibration sensor), a steering wheel angle sensor 721, any other suitable sensor, or any combination thereof. In some embodiments, the communication interface 707 is configured to transmit control signals indicating motor commands to each wheel 102, 104, 106, 108 of the vehicle 100. In some embodiments, the communication interface 707 is integrated into the processing circuitry 722, the motor / brake controller 724, or both.

[0076] In some embodiments, the system may include a resolver 712, a vehicle yaw sensor 714, an orientation sensor 716, a speed sensor 718, an accelerometer sensor 720, and a steering wheel angle sensor 721. In some embodiments, control circuitry may be communicatively connected to the resolver 712 (e.g., a sensor), which may be coupled to a motor (e.g., a motor). Figure 1 The motor shafts of motors 112, 114, 116, and 118. In some embodiments, the rotary transformer 712 may be a type of transformer / electromagnetic transducer used to measure the degree of rotation of the motor shaft 405. In some embodiments, the rotary transformer 712 corresponds to... Figure 4 Rotary transformers 406 and 408. For example, rotary transformer 712 can be a type of rotating transformer comprising a cylindrical rotor and a stator. Although a rotary transformer is shown, any suitable sensor configured to measure the rotation of motor shaft 405 (or any other additionally mechanically connected shaft or axle) can be used. In some embodiments, control circuitry may be communicatively connected to one or more rotary transformers 712, which provide wheel rotation data indicative of each of the front wheels 726 and 728 and the rear wheels 730 and 732. In some embodiments, the front wheels 726 and 728 and the rear wheels 730 and 732 correspond to Figure 1The vehicle's wheels 102, 104, 106, and 108. In some embodiments, based on data provided by a resolver, the control circuitry can determine whether a wheel is slipping and monitor wheel speed in speed control mode. In some embodiments, the control circuitry is communicatively connected to one or more vehicle yaw sensors 714, which provide data indicating vehicle rotation. In some embodiments, the control circuitry is communicatively connected to one or more orientation sensors 716, which provide data indicating the orientation of vehicle 100 in 3D space. For example, orientation sensor 716 can provide data indicating the pitch angle, yaw angle, and roll angle of vehicle 100. In some embodiments, the control circuitry is communicatively connected to a speed sensor 718 that provides the current speed of vehicle 100. In some embodiments, the control circuitry is communicatively connected to an accelerometer sensor 720 that provides the current acceleration of vehicle 100. In some embodiments, control circuitry may be communicatively connected to a steering wheel angle sensor 721, which determines the wheel angles of the steerable wheels (e.g., 102 and 104) of vehicle 100. In some embodiments, in response to determining the wheel angles using the steering wheel angle sensor 721, the control circuitry may turn the steerable wheels to reduce the wheel angles before activating another driving mode. Examples of other driving modes include a vehicle yaw mode and a speed control mode. In some embodiments, the determined steering angle may be compared to a threshold angle (e.g., 10 degrees) before entering the vehicle yaw mode. In some embodiments, before entering the vehicle yaw mode and in response to the determined wheel angles exceeding the threshold angles, the control circuitry may turn the steering wheel to reduce the wheel angles. In some embodiments, in response to entering the vehicle yaw mode, vehicle 100 may cause the wheels 102 and 104 of the vehicle to automatically straighten relative to the vertical axis 170 of vehicle 100. In some implementations, the control circuitry can determine whether the vehicle 100 has stopped or moved below the maximum vehicle speed (e.g., 10 MPH, 20 MPH, or 30 MPH) before entering the speed control mode.

[0077] Figure 7 The exemplary system 700 can be used to execute Figure 5 Any or all of the exemplary steps in the process 500. Figure 7 The exemplary system 700 can be used to control according to this disclosure. Figure 1 Either of the wheel / motor configurations shown. In some implementations, not... Figure 7 All components shown need to be included in system 700.

[0078] It can be imagined that, Figures 1 to 7The steps or descriptions of each of these embodiments may be used in conjunction with any other implementation thereof. Those skilled in the art will understand that... Figures 1 to 6 Some steps or descriptions of each of the above may be optional and may be omitted in some embodiments. More generally, the above disclosure is intended to be exemplary and not restrictive. Furthermore, relative to... Figures 1 to 6 The steps and descriptions described may be performed in an alternating order or in parallel to further serve the purposes of this disclosure. For example, each of these steps may be performed in any order or in parallel or substantially simultaneously to reduce the lag of the system or method or to increase its speed. Furthermore, it should be noted that, relative to... Figures 1 to 4 Any of the devices or equipment discussed can be used to perform Figure 5 One or more of the steps in the process.

[0079] It will be apparent to those skilled in the art that the methods involved in this disclosure can be embodied in a computer program product comprising a computer-usable and / or readable medium. For example, such a computer-usable medium may consist of a read-only memory device (such as a CD-ROM or conventional ROM device) or a random access memory (such as a hard disk drive or computer disk) on which computer-readable program code is stored. It should also be understood that processing circuitry may be used to perform the methods, techniques, and processes involved in this disclosure. Processing circuitry may, for example, be a general-purpose processor, a custom integrated circuit (e.g., an ASIC), or a field-programmable gate array (FPGA) within any vehicle 100.

[0080] The foregoing description is merely illustrative of the principles of this disclosure, and various modifications can be made by those skilled in the art without departing from the scope of this disclosure. The above embodiments are presented for illustrative purposes and not for limitation. This disclosure may also take many forms other than those expressly described herein. Therefore, it should be emphasized that this disclosure is not limited to the methods, systems, and apparatus expressly disclosed, but is intended to include variations and modifications thereof, which are within the spirit of the following claims.

Claims

1. A method for controlling the speed of wheels of a vehicle, the method comprising: Determine the clearance between one or more wheels of a plurality of wheels and one or more ground surfaces; In response to determining the gap, the system automatically enters speed control mode; In the speed control mode: The target wheel speed of each of the multiple wheels of the vehicle is determined based on the accelerator pedal input. Monitor the wheel speed of each of the plurality of wheels of the vehicle; For each of the plurality of wheels, a difference is determined based on the monitored wheel speed and the target wheel speed; as well as The torque for each of the plurality of wheels is adjusted based on the difference to achieve the target wheel speed, wherein each of the plurality of wheels is connected to a corresponding motor configured to provide the torque.

2. The method according to claim 1, wherein, One or more of the target wheel speeds cause the vehicle to rotate to zero radius.

3. The method according to claim 1, wherein, Each corresponding motor includes an electric motor, and wherein monitoring the wheel speed of each of the plurality of wheels of the vehicle includes: Signals from sensors coupled to the motor shaft of the electric motor are monitored, wherein each sensor indicates the amount of rotation of the corresponding motor shaft; and The speed of each wheel is calculated based on the corresponding signal in the monitored signals.

4. The method according to claim 1, wherein, Each of the motors comprises an independent electric motor having a motor shaft, and each of the motor shafts includes a sensor; the method further comprises: One or more signals from each of the sensors are determined, wherein the wheel speed of each of the plurality of wheels is monitored based at least on the one or more signals.

5. The method according to claim 1, wherein, The difference between the monitored wheel speed and the target wheel speed for one or more of the plurality of wheels indicates that the wheel speed exceeds the target wheel speed, and wherein the torque for the one or more of the plurality of wheels is adjusted in opposite directions to reduce the wheel speed when the one or more of the plurality of wheels spins.

6. The method according to claim 1, wherein, The torque is supplied to each of the plurality of wheels in a response time of less than 100 microseconds.

7. The method according to claim 1, further comprising: Detect one or more inclined surfaces associated with the plurality of wheels; as well as The maximum wheel speed of less than 30 MPH is determined based on one or more of the downslope surfaces.

8. The method according to claim 1, wherein, The adjustment of the torque for each of the plurality of wheels to achieve the target wheel speed includes: Provide open-loop forward torque to the wheel on the first side of the vehicle; and Provides open-loop rearward torque to the wheels on the second side of the vehicle. The first side is one of the left and right sides of the vehicle, and the second side is one of the left and right sides of the vehicle, and the second side is opposite to the first side.

9. The method according to claim 1, further comprising: Enter vehicle yaw mode; When operating in the vehicle yaw mode: Provide open-loop torque to the plurality of wheels of the vehicle; Identify slippage of one or more of the plurality of wheels of the vehicle; and In response to the identification of slippage of one or more of the plurality of wheels, a closed-loop torque is provided to the one or more wheels of the vehicle identified as slipping.

10. The method according to claim 1, wherein, The plurality of wheels includes four wheels, and the vehicle includes four electric motors, each of the four electric motors being configured to provide the torque to a corresponding one of the four wheels.

11. A system for controlling the speed of wheels of a vehicle, the system comprising: Input circuit, the input circuit being configured to receive accelerator pedal input Control circuit, the control circuit being configured to: Determine the clearance between one or more wheels of a plurality of wheels and one or more ground surfaces; In response to determining the gap, the system automatically enters speed control mode; In the speed control mode: The target wheel speed of each of the multiple wheels of the vehicle is determined based on the accelerator pedal input. Monitor the wheel speed of each of the plurality of wheels of the vehicle; For each of the plurality of wheels, a difference is determined based on the monitored wheel speed and the target wheel speed; as well as The torque for each of the plurality of wheels is adjusted based on the difference to achieve the target wheel speed, wherein each of the plurality of wheels is connected to a corresponding motor configured to provide the torque.

12. The system according to claim 11, wherein, One or more of the target wheel speeds cause the vehicle to rotate to zero radius.

13. The system according to claim 11, wherein, Each respective motor includes an electric motor, and the control circuit is configured to monitor the wheel speed of each of the plurality of wheels of the vehicle in such a way that: Signals from sensors coupled to the motor shaft of the electric motor are monitored, wherein each sensor indicates the amount of rotation of the corresponding motor shaft, and The speed of each wheel is calculated based on the corresponding signal in the monitored signals.

14. The system according to claim 11, wherein, Each of the motors includes an independent electric motor with a motor shaft, and each of the motor shafts includes a sensor; the control circuit is further configured to: One or more signals from each of the sensors are determined, wherein the wheel speed of each of the plurality of wheels is monitored based at least on the one or more signals.

15. The system according to claim 11, wherein, The difference between the monitored wheel speed and the target wheel speed for one or more of the plurality of wheels indicates that the wheel speed exceeds the target wheel speed, and When one or more of the plurality of wheels spin, the torque for one or more of the plurality of wheels is adjusted in opposite directions to reduce the wheel speed.

16. The system according to claim 11, wherein, The control circuit is configured to provide the torque to each of the plurality of wheels, wherein providing the torque to each of the plurality of wheels is performed with a reaction speed of less than 100 microseconds.

17. The system according to claim 11, wherein, The control circuit is also configured to: Detect one or more inclined surfaces associated with the plurality of wheels, and The maximum wheel speed of less than 30 MPH is determined based on one or more of the downslope surfaces.

18. The system according to claim 11, wherein, The control circuit is configured to adjust the torque for each of the plurality of wheels to achieve the target wheel speed in the following manner: Provide open-loop forward torque to the wheel on the first side of the vehicle; and Provide open-loop rearward torque to the wheels on the second side of the vehicle, and The first side is one of the left and right sides of the vehicle, and the second side is one of the left and right sides of the vehicle, and the second side is opposite to the first side.

19. A vehicle, the vehicle comprising: Multiple electric motors, each electric motor including a motor shaft connected to a corresponding wheel of the multiple wheels of the vehicle; An accelerator pedal, the accelerator pedal being configured to provide an accelerator pedal input; Power electronic devices configured to output power to each of the plurality of electric motors to generate a corresponding torque to a corresponding wheel; Multiple sensors, each configured to output a signal indicating the wheel speed of the corresponding wheel of the vehicle; and The system according to any one of claims 11 to 18, wherein the input circuit is configured to receive the signals from the accelerator pedal input and the plurality of sensors; and The control circuit is configured as follows: The target wheel speed of each of the multiple wheels of the vehicle is determined based on the accelerator pedal input. The signals from the plurality of sensors are used to monitor the wheel speed of each of the plurality of wheels.

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