System and method for steering a vehicle to reduce yaw

Abstract

A method of operating a vehicle includes receiving a lateral motion request from a lateral selection device on the vehicle from a driver of the vehicle while the vehicle is in motion, determining a lateral velocity and a yaw rate of the vehicle that satisfy the lateral motion request, and determining a front wheel path and a rear wheel path that satisfy the lateral velocity and the yaw rate of the vehicle. The method also includes directing the front wheels of the vehicle to follow the front wheel path with a front wheel steering system and directing the rear wheels on the vehicle to follow the rear wheel path with a rear wheel steering system.

Description

Background Technology

[0001] This disclosure relates to vehicle maneuvering, and more specifically to systems and methods for maneuvering a vehicle to reduce yaw.

[0002] During travel, many factors can contribute to passenger comfort in a vehicle. One way to improve passenger comfort is through suspension tuning to remove roughness from changes in road surface. Additionally, roads with certain contours (such as curved roads) can cause passengers to experience motion due to the vehicle's cyclical movement. In these situations, the driver can reduce the vehicle's speed to improve passenger comfort or choose a different route. Summary of the Invention

[0003] This document discloses a method for operating a vehicle. The method includes: receiving a lateral movement request from a driver lateral selection device on the vehicle while the vehicle is in motion; determining the lateral velocity and yaw rate of the vehicle to satisfy the lateral movement request; and determining the front wheel path and rear wheel path to satisfy the lateral velocity and yaw rate of the vehicle. The method further includes guiding the front wheels of the vehicle to follow the front wheel path using a front wheel steering system and guiding the rear wheels of the vehicle to follow the rear wheel path using a rear wheel steering system.

[0004] In one aspect of this disclosure, the lateral movement request is based at least in part on the position of the handwheel on the vehicle, determined by the handwheel position sensor.

[0005] In one aspect of this disclosure, the front wheel path includes the maximum front wheel angle of each front wheel in a first rotational direction, and the rear wheel path includes the maximum rear wheel angle in the first rotational direction.

[0006] In one aspect of this disclosure, the front wheel path includes a maximum front wheel angle in a first rotational direction and a maximum front wheel angle in a second rotational direction.

[0007] In one aspect of this disclosure, the rear wheel path includes a maximum rear wheel angle in a first rotational direction and a maximum rear wheel angle in a second rotational direction.

[0008] In one aspect of this disclosure, the lateral movement request from the driver's lateral selection device includes the desired direction and magnitude.

[0009] In one aspect of this disclosure, size includes one of a set of predetermined size levels.

[0010] In one aspect of this disclosure, the determined yaw rate for satisfying the lateral movement request is based on the magnitude of the lateral movement request from the driver's lateral selection device.

[0011] In one aspect of this disclosure, a front-wheel steering system includes a steer-by-wire system having at least one front-wheel actuator configured to generate a front wheel path.

[0012] In one aspect of this disclosure, the rear-wheel steering system includes a steer-by-wire system having at least one rear-wheel actuator configured to generate a rear wheel path.

[0013] This document discloses a non-transitory computer-readable storage medium containing programming instructions that, when executed by a processor, are operable to perform a method. The method includes: receiving a lateral movement request from a driver's lateral selection device on the vehicle while the vehicle is in motion; determining a lateral velocity and yaw rate of the vehicle to satisfy the lateral movement request; and determining a front wheel path and a rear wheel path to satisfy the lateral velocity and yaw rate of the vehicle. The method further includes guiding the front wheels of the vehicle to follow a front wheel path using a front wheel steering system and guiding the rear wheels of the vehicle to follow a rear wheel path using a rear wheel steering system.

[0014] This document discloses a vehicle. The vehicle includes: a body that at least partially defines a passenger compartment; a front steering system configured to generate front wheel angles using a pair of front wheels; a rear steering system configured to generate rear wheel angles using a pair of rear wheels; at least one driver lateral selection device located within the passenger compartment; and a handwheel located within the passenger compartment and communicating with a handwheel position sensor. The vehicle also includes a controller in electrical communication with the front steering system, the rear steering system, the at least one driver lateral selection device, and the handwheel position sensor. The controller is configured to: receive a lateral movement request from the at least one driver lateral selection device on the vehicle while the vehicle is in motion; determine a lateral velocity and yaw rate of the vehicle that satisfy the lateral movement request; and determine front wheel paths and rear wheel paths that satisfy the lateral velocity and yaw rate of the vehicle.

[0015] The controller is also configured to guide the front wheels of the vehicle to follow a front wheel path using a front wheel steering system and to guide the rear wheels of the vehicle to follow a rear wheel path using a rear wheel steering system.

[0016] This invention also includes the following technical solutions:

[0017] Option 1. A method for operating a vehicle, the method comprising:

[0018] While the vehicle is in motion, a lateral movement request is received from the driver's lateral selection device on the vehicle.

[0019] Determine the lateral velocity and yaw rate of the vehicle that meet the lateral motion requirements;

[0020] Determine the front and rear wheel paths that satisfy the vehicle's lateral velocity and yaw rate; and

[0021] The front-wheel steering system guides the front wheels of the vehicle to follow the front wheel path, and the rear-wheel steering system guides the rear wheels of the vehicle to follow the rear wheel path.

[0022] Option 2. The method according to Option 1, wherein the lateral movement request is based at least in part on the position of the vehicle's upper handwheel determined by the handwheel position sensor.

[0023] Option 3. According to the method of Option 1, wherein the front wheel path includes the maximum front wheel angle of each front wheel in the first rotation direction, and the rear wheel path includes the maximum rear wheel angle in the first rotation direction.

[0024] Option 4. According to the method of Option 1, wherein the front wheel path includes the maximum front wheel angle in the first rotation direction and the maximum front wheel angle in the second rotation direction.

[0025] Option 5. According to the method of Option 4, wherein the rear wheel path includes the maximum rear wheel angle in the first rotation direction and the maximum rear wheel angle in the second rotation direction.

[0026] Option 6. The method according to Option 1, wherein the lateral movement request from the driver's lateral selection device includes the desired direction and magnitude.

[0027] Option 7. The method according to Option 6, wherein the size includes one of a plurality of predetermined size levels.

[0028] Option 8. The method according to Option 6, wherein the determined yaw rate for satisfying the lateral movement request is based on the magnitude of the lateral movement request from the driver's lateral selection device.

[0029] Option 9. The method according to Option 1, wherein the front wheel steering system includes a steer-by-wire system having at least one front wheel actuator configured to generate a front wheel path.

[0030] Option 10. The method according to Option 1, wherein the rear wheel steering system includes a steer-by-wire system having at least one rear wheel actuator configured to generate a rear wheel path.

[0031] Option 11. A non-transitory computer-readable storage medium comprising programming instructions, which, when executed by a processor, are operable to perform a method comprising:

[0032] While the vehicle is in motion, a lateral movement request is received from the driver's lateral selection device on the vehicle.

[0033] Determine the lateral velocity and yaw rate of the vehicle that meet the lateral motion requirements;

[0034] Determine the front and rear wheel paths that satisfy the vehicle's lateral velocity and yaw rate; and

[0035] The front-wheel steering system guides the front wheels of the vehicle to follow the front wheel path, and the rear-wheel steering system guides the rear wheels of the vehicle to follow the rear wheel path.

[0036] Option 12. The non-transitory computer-readable storage medium according to Option 11, wherein the front wheel path includes a maximum front wheel angle for each front wheel in a first rotational direction, and the rear wheel path includes a maximum rear wheel angle in the first rotational direction.

[0037] Option 13. The non-transitory computer-readable storage medium according to Option 11, wherein the front wheel path includes a maximum front wheel angle in a first rotational direction and a maximum front wheel angle in a second rotational direction.

[0038] Option 14. The non-transitory computer-readable storage medium according to Option 13, wherein the rear wheel path includes a maximum rear wheel angle in a first rotational direction and a maximum rear wheel angle in a second rotational direction.

[0039] Option 15. A vehicle comprising:

[0040] The body of the vehicle must at least partially limit the passenger cabin;

[0041] The front steering system is configured to generate front wheel angles using a pair of front wheels;

[0042] The rear steering system is configured to generate the rear wheel angle using a pair of rear wheels;

[0043] At least one pilot lateral selection device located within the passenger cabin;

[0044] The handwheel, located inside the cabin and communicating with the handwheel position sensor; and

[0045] A controller, which is in electrical communication with the front steering system, the rear steering system, the at least one driver lateral selection device, and the handwheel position sensor, is configured to:

[0046] While the vehicle is in motion, a lateral movement request is received from at least one driver lateral selection device on the vehicle;

[0047] Determine the lateral velocity and yaw rate of the vehicle that meet the lateral motion requirements;

[0048] Determine the front and rear wheel paths that satisfy the vehicle's lateral velocity and yaw rate; and

[0049] The front-wheel steering system guides the front wheels of the vehicle to follow the front wheel path, and the rear-wheel steering system guides the rear wheels of the vehicle to follow the rear wheel path.

[0050] Option 16. The vehicle according to Option 15, wherein the lateral movement request from at least one driver lateral selection device includes a desired direction and magnitude.

[0051] Option 17. The vehicle according to Option 15, wherein the at least one driver lateral selection device includes at least one of a dial, paddle shifter, or joystick.

[0052] Option 18. The vehicle according to Option 15, wherein the front wheel steering system includes a steer-by-wire system having at least one front wheel actuator configured to generate the front wheel path.

[0053] Option 19. The vehicle according to Option 15, wherein the rear-wheel steering system includes a steer-by-wire system having at least one rear-wheel actuator configured to generate a rear wheel path.

[0054] Option 20. The vehicle according to Option 15, wherein the front wheel path includes the maximum front wheel angle of the pair of front wheels in a first rotational direction, and the rear wheel path includes the maximum rear wheel angle of the pair of rear wheels in the first rotational direction. Attached Figure Description

[0055] The accompanying drawings, which are incorporated in and form a part of this specification, illustrate embodiments of the present disclosure and, together with the specification, explain the principles of the present disclosure.

[0056] Figure 1 An example vehicle with a front steering system and a rear steering system is shown schematically.

[0057] Figure 2 It shows the manipulation Figure 1 Extended control diagram of the vehicle.

[0058] Figure 3 Manipulation was shown Figure 1 Example methods for vehicles.

[0059] Figure 4 It shows Figure 1 Example paths for vehicles.

[0060] Figure 5 It shows Figure 1Another example path for the vehicle. Detailed Implementation

[0061] This disclosure allows for many different forms of embodiments. Representative examples of this disclosure are shown in the accompanying drawings and are described in detail herein as non-limiting examples of the disclosed principles. Therefore, elements and limitations described in the abstract, introduction, summary, and detailed description sections but not expressly set forth in the claims should not be incorporated into the claims, individually or collectively, by implication, inference, or otherwise.

[0062] For the purposes of this specification, unless otherwise stated, the use of the singular includes the plural, and vice versa; the terms “and” and “or” should be both conjunctions and disjunctive words; and the words “including,” “contains,” “including,” “having,” etc., should mean “including, but not limited to.” Furthermore, approximate words such as “approximately,” “almost,” “substantially,” “generally,” “roughly,” etc., may be used herein in the sense of “being, near, or almost being” or “within 0-5% of,” or “within acceptable manufacturing tolerances,” or logical combinations thereof. As used herein, a component “configured” to perform a specified function is capable of performing the specified function without alteration, rather than merely having the potential to perform the specified function after further modification. In other words, when explicitly configured to perform a specified function, the described hardware is specifically selected, created, implemented, utilized, programmed, and / or designed for the purpose of performing the specified function.

[0063] This document describes embodiments of the present disclosure in terms of functional and / or logical block components and various processing steps. It should be understood that such block components can be implemented by multiple hardware, software, and / or firmware components configured to perform specified functions. For example, embodiments of the present disclosure may employ various integrated circuit components, such as memory elements, digital signal processing elements, logic elements, lookup tables, etc., which can perform multiple functions under the control of one or more microprocessors or other control devices. Furthermore, those skilled in the art will appreciate that embodiments of the present disclosure can be practiced in conjunction with multiple systems, and the systems described herein are merely exemplary embodiments of the present disclosure.

[0064] For the sake of brevity, techniques related to signal processing, data fusion, signaling, control, and other functional aspects of the system (as well as the various operating components of the system) may not be described in detail herein. Furthermore, the connecting lines shown in the various figures included herein are intended to represent exemplary functional relationships and / or physical couplings between various elements. It should be noted that alternative or additional functional relationships or physical connections may exist in the embodiments of this disclosure.

[0065] refer to Figure 1Vehicle 10 typically includes a chassis 12, a body 14, front wheels, and rear wheels 17. The body 14 is mounted on the chassis 12 and substantially surrounds the components of vehicle 10, defining the passenger compartment. The body 14 and chassis 12 may together form a frame. Each wheel 17 is rotatably coupled to the chassis 12 near a corresponding corner of the body 14. The wheels 17 are supported by a front axle 19F and a rear axle 19R.

[0066] As shown, vehicle 10 typically includes a propulsion system 20, a drivetrain 22, a steering system 24, a braking system 26, a sensor system 28, an actuator system 30, at least one driver lateral selection device 32, at least one controller 34, and a communication system 36. In various embodiments, propulsion system 20 may include an electric motor, such as a traction motor, and / or a fuel cell propulsion system. Vehicle 10 also includes a battery (or battery pack) 21 electrically connected to propulsion system 20. Thus, battery pack 21 is configured to store electrical energy and supply electrical energy to propulsion system 20. Furthermore, propulsion system 20 may include an internal combustion engine. Drivetrain 22 is configured to transmit power from propulsion system 20 to wheels 17 according to a selectable speed ratio. According to various embodiments, drivetrain 22 may include a step-ratio automatic transmission, a continuously variable transmission, or other suitable transmission. Braking system 26 is configured to provide braking torque to wheels 17. In various embodiments, braking system 26 may include friction brakes, brake-by-wire brakes, regenerative braking systems, such as electric motors, and / or other suitable braking systems. Steering system 24 affects the position of wheels 17. Although depicted as including a steering wheel for illustrative purposes, in some embodiments contemplated within the scope of this disclosure, the steering system 24 may not include a steering wheel.

[0067] Sensor system 28 includes one or more sensors 40 (i.e., sensing devices) that sense observable conditions of the external and / or internal environment of vehicle 10. Sensors 40 communicate with controller 34 and may include, but are not limited to, one or more radars, one or more lidar sensors, one or more ground-penetrating radar (GPR) sensors, one or more global positioning system (GPS) devices, one or more cameras (e.g., optical cameras and / or thermal cameras, such as rear cameras and / or front cameras), brake pedal position sensors, accelerator pedal position sensors, steering angle sensors, speed sensors, wheel speed sensors, ride height sensors, steering angle sensors, ultrasonic sensors, one or more inertial measurement units (IMUs) and / or other sensors.

[0068] Actuator system 30 includes one or more actuator devices 42 that control one or more vehicle features, such as, but not limited to, propulsion system 20, drivetrain 22, steering system 24 including front and rear steering components, and braking system 26. In this disclosure, steering system 24 includes a front steering system 25 for turning the front wheels 17 and a rear steering system 43 for steering the rear wheels 17 independently of the front wheels 17, such as an active rear steering (ARS) system. Furthermore, each of the front and rear steering systems is a drive-by-wire system with no direct mechanical connection between the steering wheel and the wheels 17. In various embodiments, vehicle features may further include interior and / or exterior vehicle features, such as, but not limited to, doors, trunk, and cabin features, such as air conditioning, music, lighting, etc. (not numbered). For example, actuator devices 42 include accelerator pedals, brake pedals, etc.

[0069] The controller 34 includes at least one processor 44 and a non-transitory computer-readable storage device or medium 46. The processor 44 may be a custom or commercially available processor, a central processing unit (CPU), a graphics processing unit (GPU), an auxiliary processor among several processors associated with the controller 34, a semiconductor-based microprocessor (in the form of a microchip or chipset), a combination of microprocessors, or generally a device for executing instructions. The computer-readable storage device or medium 46 may include volatile and non-volatile storage, such as read-only memory (ROM), random access memory (RAM), and keep-alive memory (KAM). KAM is a permanent or non-volatile memory that can be used to store various operational variables when the processor 44 is powered off. The computer-readable storage device or medium 46 may be implemented using many other memory devices, such as PROM (programmable read-only memory), EPROM (electrical PROM), EEPROM (electrically erasable PROM), flash memory, or another electrical, magnetic, optical, or combined memory device capable of storing data, some of which represent executable instructions used by the controller 34 in controlling the vehicle 10.

[0070] The instructions may include one or more separate programs, each comprising an ordered list of executable instructions for implementing logical functions. When executed by processor 44, the instructions receive and process signals from sensor system 28, execute logic, calculations, methods, and / or algorithms for automatically controlling components of vehicle 10, and generate control signals to actuator system 30 to automatically control components of vehicle 10 based on logic, calculations, methods, and / or algorithms. Although Figure 1A single controller 34 is shown, but embodiments of vehicle 10 may include a number of controllers 34 that communicate via a suitable communication medium or a combination of communication media and cooperate to process sensor signals, execute logic, calculations, methods and / or algorithms, and generate control signals to automatically control the features of vehicle 10.

[0071] Vehicle 10 includes a human-machine interface (HMI) 23, which may be a central stack screen or a driver information center. HMI 23 interacts with the user to display information and receive confirmations, activation, cancellation commands, etc. HMI 23 may be configured as an alarm, such as a speaker providing sound, haptic feedback in a vehicle seat or other object, a visual display, or other devices suitable for providing notifications to the vehicle operator of vehicle 10. HMI 23 communicates electronically with controller 34 and is configured to receive input from a user (e.g., a vehicle operator). Therefore, controller 34 is configured to receive input from the user via HMI 23. HMI 23 includes a display configured to show information to a user (e.g., a vehicle operator or passenger) and may include one or more speakers to provide audible notifications to the vehicle operator.

[0072] Figure 2 An extended control diagram 60 for maneuvering vehicle 10 is shown. Control diagram 60 includes a driver input section 62, a control section 64, and an actuator section 66. The driver input section 62 includes at least one driver lateral selection device 32, a handwheel HW forming part of steering system 24, and an accelerator pedal 68 connected to accelerator pedal position sensor 40. An active cruise control system (ACC) 69 may also be associated with the accelerator pedal 68.

[0073] In the example shown, the driver's lateral selection device 32 may include a rotary dial D on the center console, a lever L on the steering column, or a paddle P located near the handwheel HW. Signals from the driver's lateral selection device 32 and the handwheel HW are sent to the driver command controller 70. The driver command controller 70 interprets the signals from the driver's lateral selection device 32 and the handwheel HW as lateral speed V. y And yaw rate, to describe the desired lateral motion of vehicle 10. Lateral velocity V y The yaw rate is then sent to the vehicle motion controller 72. Additionally, the lateral velocity V is also calculated, if desired. y The yaw rate can be directly provided to the front steering system 25 and the rear steering system 43 via feedforward FF communication to increase response time. The driver command controller 70 can also select the lateral speed V based on road friction in the vehicle's handling area. y And yaw rate.

[0074] When the vehicle motion controller 72 receives the lateral velocity V y When the yaw rate is measured, the vehicle motion controller 72 converts these parameters into control signals, which are sent to the front steering system 25 to create wheel angles using the front wheels 17 and to the rear steering system 43 to create wheel angles using the rear wheels 17. The vehicle motion controller 72 can also send control signals to the brakes 26 and the accelerator pedal 68 to further control the lateral movement of the vehicle 10.

[0075] Figure 3 An example method 100 for maneuvering a vehicle 10 along a road is shown. A feature of this disclosure is that it allows the vehicle 10 to move laterally along the road with a reduced yaw rate in certain situations to improve vehicle passenger comfort. Example method 100 begins at box 102 (“Start”). The method progresses from box 102 to box 104.

[0076] At block 104 (“Lateral Movement Request”), method 100 receives a lateral movement request from one of the driver lateral selection devices 32. A feature of this disclosure is that the lateral movement requested by one of the driver lateral selection devices 32 is separate from the input received by the handwheel HW. When a lateral movement request is received from the turntable D, the direction of rotation corresponds to the desired lateral direction of vehicle movement, and the magnitude of the rotational travel of the turntable D corresponds to the desired rate of lateral change in the lateral direction. Similarly, when the driver lateral selection device 32 includes a lever L, the direction of lateral movement can be selected similarly to a blinker, and the magnitude of the lateral change can correspond to the length of time the lever L is held depressed in a given direction or the magnitude of its travel. Furthermore, when the driver lateral selection device 32 includes a paddle P, the direction of lateral movement corresponds to whether the left or right paddle P is selected, and the rate of lateral change can correspond to the length of time the selected paddle P is held depressed. With the lateral movement request received, method 100 proceeds to block 106. Furthermore, in one example, a lateral movement request could include input from the handwheel HW, since the handwheel HW is part of the steer-by-wire system on vehicle 10.

[0077] At box 106 (“Determine Lateral Velocity and Yaw Rate”), the lateral velocity and yaw rate of vehicle 10 that will satisfy the requested lateral movement are determined. In one example, the lateral velocity and yaw rate of vehicle 10 are based on input from only one of the driver lateral selection devices 32, and in another example, the lateral velocity and yaw rate of vehicle 10 are based on a combination or mixture of inputs from the driver lateral selection device 32 and the handwheel HW. As discussed above, driver command controller 70 determines the lateral velocity and yaw rate of vehicle 10 based on the requested lateral movement input. Driver command controller 70 may determine the lateral velocity and yaw rate based on a lookup table or by an algorithm. Method 100 then proceeds to box 108.

[0078] At block 108 (“Determining Wheel Angles”), method 100 utilizes vehicle motion controller 72 to convert the desired lateral velocity and yaw rate into control signals for the front steering system 25 and the rear steering system 43. The control signals from vehicle motion controller 72 correspond to the wheel angles of the front wheels 17 and the rear wheels 17. The wheel angles of the front and rear wheels 17 correspond to the front wheel path and the rear wheel path. A feature of this disclosure is that it allows the driver of vehicle 10 to create lateral movement of vehicle 10 with almost no yaw rate without providing input to the handwheel HW. Furthermore, this disclosure also allows for reduction of the yaw rate based on input from the driver's lateral selection device 32 and the handwheel HW. This improves vehicle passenger comfort while also providing a rapid vehicle handling response. Using the determined wheel angles, method 100 proceeds to block 110.

[0079] At box 110 (“Guiding the Vehicle”), method 100 guides the front steering system 25 via vehicle motion controller 72 to create a desired wheel angle with the front wheels 17 using at least one actuator 42 (e.g., a front wheel actuator). Similarly, method 100 guides the rear steering system 43 via vehicle motion controller 72 to create a desired wheel angle with the rear wheels 17 using at least one actuator 42 (e.g., a rear wheel actuator). In addition to steering, as discussed below, method 100 can also modify vehicle propulsion and braking.

[0080] Furthermore, depending on the control signals generated to satisfy the lateral movement request, the vehicle motion controller 72 can also cause the actuator 42 to make changes to the vehicle's propulsion or braking. For example, the control signals generated by the vehicle motion controller 72 can actuate the brakes 26 at one or more corners of the vehicle 10 to create an additional change in yaw rate beyond that created by the wheels, thereby satisfying the lateral movement request and / or commanding the torque vectoring of the propulsion actuator.

[0081] Figure 4A first example vehicle path 200 is shown. In example vehicle path 200, the operator of vehicle 10 provides a lateral movement request via one of the driver lateral selection devices 32, which can be satisfied with a negligible yaw rate of vehicle 10, but with a lateral velocity. In the example shown, vehicle 10 starts at an initial lateral position LS and moves through intermediate lateral positions L-I1 and L-I2 before reaching a final lateral position LF. To achieve this lateral movement, the front and rear wheels 17 follow front and rear wheel paths, respectively, which begin in a straight line at the initial lateral position LS and include maximum front and rear wheel angles in a first rotational direction at one of the intermediate lateral positions L-I1 or L-I2 before returning to a straight line at the final lateral position LF.

[0082] Figure 5 A second example vehicle path 300 is shown. In example vehicle path 300, the operator of vehicle 10 provides a lateral movement request via one of the driver lateral selection devices 32, with or without additional input to the handwheel HW, which requires a combination of lateral velocity and yaw rate to satisfy. In the example shown, vehicle 10 starts at an initial lateral position LS and moves through intermediate lateral positions L-I1 and L-I2 before reaching a final lateral position LF. To achieve this lateral movement, the front and rear wheels follow front and rear wheel paths, respectively, which begin in a straight line at the initial lateral position LS and include a first maximum front and rear wheel angle in a first rotational direction at the first intermediate lateral position L-I1. Before returning to a straight line at the final lateral position LF, the front and rear wheels also include a second maximum front and rear wheel angle in a second rotational direction at the second intermediate lateral position L-I2.

[0083] Example vehicle paths 200 and 300 represent vehicle maneuvers of different degrees corresponding to inputs to one or more of the handwheel HW and the driver's lateral selection device 32.

[0084] The terms “a” and “an” do not indicate a limitation of quantity, but rather rather that at least one of the referenced items is present. The term “or” means “and / or” unless otherwise explicitly indicated by the context. Throughout the specification, reference to “an aspect” means that a particular element (e.g., a feature, structure, step, or characteristic) described in connection with that aspect is included in at least one aspect described herein and may or may not be present in other aspects. Furthermore, it is to be understood that the described elements may be combined in suitable manner in various aspects.

[0085] While the above disclosure has been described with reference to exemplary embodiments, those skilled in the art will understand that various changes can be made without departing from its scope, and equivalents can replace its elements. Furthermore, many modifications can be made to suit particular situations or materials to the teachings of this disclosure without departing from its scope. Therefore, it is intended that this disclosure be limited to the specific embodiments disclosed, but will include embodiments falling within its scope.

Claims

1. A method of operating a vehicle, the method comprising: While the vehicle is in motion, a lateral movement request is received from the driver's lateral selection device on the vehicle. Determine the lateral velocity and yaw rate of the vehicle that meet the lateral motion requirements; Determine the front wheel path and rear wheel path that satisfy the vehicle's lateral velocity and yaw rate; and The front-wheel steering system guides the front wheels of the vehicle to follow the front wheel path, and the rear-wheel steering system guides the rear wheels of the vehicle to follow the rear wheel path.

2. The method of claim 1, wherein the lateral movement request is based at least in part on the position of the vehicle's upper handwheel determined by the handwheel position sensor.

3. The method according to claim 1, wherein, The front wheel path includes the maximum front wheel angle of each front wheel in the first rotation direction, and the rear wheel path includes the maximum rear wheel angle in the first rotation direction.

4. The method according to claim 1, wherein, The front wheel path includes the maximum front wheel angle in the first rotation direction and the maximum front wheel angle in the second rotation direction.

5. The method according to claim 4, wherein, The rear wheel path includes the maximum rear wheel angle in the first rotation direction and the maximum rear wheel angle in the second rotation direction.

6. The method according to claim 1, wherein, The lateral movement request from the driver's lateral selection device includes the desired direction and magnitude.

7. The method of claim 6, wherein the size includes one of a plurality of predetermined size levels.

8. The method according to claim 6, wherein, The determined yaw rate for satisfying the lateral movement request is based on the magnitude of the lateral movement request from the driver's lateral selection device.

9. The method according to claim 1, wherein, The front wheel steering system includes a steer-by-wire system having at least one front wheel actuator configured to generate a front wheel path.

10. The method according to claim 1, wherein, The rear-wheel steering system includes a steer-by-wire system having at least one rear-wheel actuator configured to generate a rear wheel path.

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