Vehicle body motion control method and device

Abstract

The invention provides a vehicle body motion control method and device, and the method comprises the steps: obtaining at least one of a target track, a transverse position error and a course angle error of a vehicle under the condition of rear wheel steering failure; judging whether the vehicle is in a target driving state or not, the target driving state comprises at least one of an error between the target track and an actual track of the vehicle within a preset track error range, a transverse position error within a preset distance error range and an error between a course angle error and a rear wheel jamming angle of the vehicle within a preset angle error range; according to the method, front wheel steering compensation is carried out when single-point failure of rear wheel steering occurs, compensation feedback is carried out according to the target track, the transverse position error and the course angle error, the effect of closed-loop control is achieved, the vehicle running track is corrected, and the driving stability of the vehicle is improved. And the safety requirement of L4-level automatic driving is met.

Description

Technical Field

[0001] The present disclosure relates to the field of data processing, and in particular to a vehicle body motion control method and device. Background Art

[0002] As traditional vehicle technology reaches a bottleneck, autonomous driving has become a key development direction for the future transformation and upgrading of the automotive industry. Autonomous driving always requires functional safety, a fundamental requirement. The smarter the vehicle, the higher the safety standards required.

[0003] Autonomous driving levels range from L0 to L5. Higher levels indicate a higher degree of automation and higher safety standards. Currently, rear-wheel steering technology for passenger cars is limited to a few high-end models, and these are all non-redundant systems for L2 autonomous driving. There is no redundant rear-wheel steering system suitable for L4 autonomous driving, nor is there a rear-wheel steering technology that can transition from L2 to L4. In the event of a single-point failure in the rear-wheel steering system, the rear wheels could become stuck, causing the vehicle to deviate from its target trajectory. This poses a safety hazard and prevents the safety requirements of L4 autonomous driving from being met. Summary of the Invention

[0004] The present disclosure provides a vehicle body motion control method, device, electronic device, storage medium, and program product.

[0005] According to a first aspect of the present disclosure, a vehicle body motion control method is provided, the method comprising: in the event of rear-wheel steering failure, obtaining at least one of a target trajectory, a lateral position error, and a heading angle error of the vehicle; determining whether the vehicle is in a target driving state, wherein the target driving state comprises at least one of: an error between the target trajectory and the actual trajectory of the vehicle being within a preset trajectory error range, a lateral position error being within a preset distance error range, and an error between the heading angle error and a rear wheel dead angle of the vehicle being within a preset angle error range; and in response to the vehicle not being in the target driving state, sending a steering wheel angle command to a front-wheel steering actuator, wherein the steering wheel angle command is used to instruct the front-wheel steering actuator to control the front wheels to perform a steering action according to the rear wheel dead angle.

[0006] In some embodiments, the rear wheel steering failure includes: any one of the following: the actual rack position and / or rear wheel actuator status feedback from the rear wheel actuator is not received within a preset feedback time, and the actual rack position and / or rear wheel actuator status received is abnormal.

[0007] In some embodiments, the method further includes: in the event of rear wheel steering failure, determining whether a position sensor of the rear wheel steering has failed; if the position sensor of the rear wheel steering has not failed, reading the rear wheel deadlock angle of the vehicle from the position sensor of the rear wheel steering system, or if the position sensor of the rear wheel steering system has failed, obtaining the rear wheel deadlock angle before the failure.

[0008] In some embodiments, obtaining the target trajectory of the vehicle includes: obtaining the actual position of the vehicle at a first moment from a vehicle position sensor, where the first moment is the current moment; obtaining the preview position of the vehicle at a second moment, where the second moment is the moment after the current moment plus a preset time; and obtaining the target trajectory of the vehicle based on the actual position at the first moment and the preview position at the second moment.

[0009] In some embodiments, obtaining the preview position of the vehicle at the second moment includes: determining the preview position of the vehicle at the second moment through a preset preview model, or fitting a relationship curve between time and preview position based on at least one of vehicle parameters, historical trajectories of the vehicle in different application scenarios, and the motion state of the vehicle, and determining the preview position of the vehicle at the second moment from the relationship curve.

[0010] In some embodiments, obtaining the lateral position error and heading angle error of the vehicle includes: obtaining the actual trajectory of the vehicle from a vehicle position sensor; calculating the coordinate difference between the vehicle's position on the actual trajectory and the vehicle's position on the target trajectory to determine the vehicle's lateral position error and heading angle error.

[0011] According to a second aspect of the present disclosure, a vehicle body motion control device is provided, which includes: an acquisition unit for acquiring at least one of a target trajectory, a lateral position error, and a heading angle error of a vehicle when rear-wheel steering fails; a judgment unit for judging whether the vehicle is in a target driving state, wherein the target driving state includes at least one of: an error between the target trajectory and the actual trajectory of the vehicle is within a preset trajectory error range, a lateral position error is within a preset distance error range, and an error between the heading angle error and a rear wheel dead angle of the vehicle is within a preset angle error range; and a compensation unit for sending a steering wheel angle command to a front-wheel steering actuator in response to the vehicle not being in the target driving state, wherein the steering wheel angle command is used to instruct the front-wheel steering actuator to control the front wheels to perform a steering action according to the rear wheel dead angle.

[0012] According to a third aspect of the present disclosure, an electronic device is provided, comprising: at least one processor; and a memory connected to the at least one processor for vehicle body motion control; wherein the memory stores instructions that can be executed by the at least one processor, and the instructions are executed by the at least one processor to enable the at least one processor to execute the method of the aforementioned first aspect.

[0013] According to a fourth aspect of the present disclosure, a non-transitory computer-readable storage medium storing computer instructions is provided, wherein the computer instructions are used to enable a computer to execute the method of the aforementioned first aspect.

[0014] According to a fifth aspect of the present disclosure, a computer program product is provided, comprising a computer program, which implements the method of the first aspect when executed by a processor.

[0015] The vehicle body motion control method provided by an embodiment of the present disclosure includes: obtaining at least one of a target trajectory, a lateral position error, and a heading angle error of a vehicle in the event of a rear-wheel steering failure; determining whether the vehicle is in a target driving state, wherein the target driving state includes at least one of: an error between the target trajectory and the vehicle's actual trajectory being within a preset trajectory error range, a lateral position error being within a preset distance error range, and an error between the heading angle error and a rear wheel dead angle of the vehicle being within a preset angle error range; and sending a steering wheel angle command to a front-wheel steering actuator in response to the vehicle not being in the target driving state, wherein the steering wheel angle command is used to instruct the front-wheel steering actuator to control the front wheels to perform a steering action according to the rear wheel dead angle. This solution performs front-wheel steering compensation in the event of a single-point failure in the rear-wheel steering, and provides compensation feedback based on the target trajectory, lateral position error, and heading angle error, thereby achieving a closed-loop control effect to correct the vehicle's driving trajectory. In the event of a sudden rear-wheel steering failure, the solution can help the vehicle fail safely and stop. This solution can be applied to L4 autonomous driving to meet the safety requirements of L4 autonomous driving.

[0016] It should be understood that the content described in this section is not intended to identify the key or important features of the embodiments of the present application, nor is it intended to limit the scope of the present application. Other features of the present application will become easily understood through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The accompanying drawings are used to better understand the present invention and do not constitute a limitation of the present invention.

[0018] Figure 1 A schematic flow chart of a vehicle body motion control method provided in an embodiment of the present disclosure;

[0019] Figure 2 A schematic flow chart of a vehicle body motion control method provided in an embodiment of the present disclosure;

[0020] Figure 3 An example diagram of a vehicle body motion control architecture provided by an embodiment of the present disclosure;

[0021] Figure 4 A schematic flow chart of a vehicle body motion control method provided in an embodiment of the present disclosure;

[0022] Figure 5 A schematic flow chart of a vehicle body motion control method provided in an embodiment of the present disclosure;

[0023] Figure 6An example diagram of obtaining a target trajectory provided by an embodiment of the present disclosure;

[0024] Figure 7 An example diagram of a vehicle body motion control method provided by an embodiment of the present disclosure;

[0025] Figure 8 A schematic structural diagram of a vehicle body motion control device provided by an embodiment of the present disclosure;

[0026] Figure 9 A schematic block diagram of an exemplary electronic device 600 is provided for an embodiment of the present disclosure. DETAILED DESCRIPTION

[0027] The following description of exemplary embodiments of the present disclosure is made in conjunction with the accompanying drawings, including various details of the embodiments of the present disclosure to facilitate understanding. These details should be considered as merely exemplary. Therefore, those skilled in the art will recognize that various changes and modifications may be made to the embodiments described herein without departing from the scope and spirit of the present disclosure. Similarly, for the sake of clarity and conciseness, descriptions of well-known functions and structures are omitted in the following description.

[0028] The following describes in detail with reference to the accompanying drawings a vehicle body motion control method, device, electronic device, storage medium, and program product proposed in the present disclosure.

[0029] Figure 1 A vehicle body motion control method is provided in an embodiment of the present disclosure. The method is applied to a vehicle, and the execution subject may be the vehicle's main control chip.

[0030] In some embodiments, the method may be executed by a vehicle mode management module (VMM).

[0031] like Figure 1 As shown, the method comprises the following steps:

[0032] Step 101 : When rear wheel steering fails, obtain at least one of a target trajectory, a lateral position error, and a heading angle error of the vehicle.

[0033] In some embodiments of the present disclosure, rear wheel steering failure refers to failure of a rear wheel steering actuator (Rear Wheel Steering, hereinafter referred to as RWS), wherein the rear wheel steering actuator is used to control the rear wheel steering angle of the vehicle. Specifically, the rear wheel steering failure may be caused by mechanical jamming or software logic failure.

[0034] In some embodiments, the RWS is controlled by the vehicle's vehicle dynamic management (VDM). The RWS sends information such as the RWS status and actual rack position to the VDM, and the VDM feeds back the RWS status and actual rack position to the VMM. When the RWS fails, the VMM cannot receive the RWS status and actual rack position information fed back by the VDM.

[0035] Furthermore, in some embodiments, whether the vehicle is in a rear-wheel steering failure situation can be determined by any one of the following: the actual rack position and / or RWS status not being received as RWS feedback within a preset feedback time, or the actual rack position and / or RWS status being received being abnormal.

[0036] In some embodiments, the vehicle adds target trajectory, lateral position error, and heading angle error interfaces. The target trajectory, lateral position error, and heading angle error can all be used to measure vehicle body motion and provide vehicle body feedback.

[0037] In some embodiments, the target trajectory is a target motion trajectory generated by the vehicle's automatic driving module based on the surrounding environmental information. Due to various interference factors, the actual driving trajectory of the vehicle may deviate from the ideal target trajectory.

[0038] In some embodiments, the vehicle contains a sensor for obtaining vehicle position information, such as a high-precision GPS, which can be used to obtain the current position of the vehicle. The position of the vehicle's preview point is determined by calculation using an existing preview model, or by fitting a curve between time and the preview point based on multiple parameters such as vehicle parameters, historical trajectories in different application scenarios, and motion status. The preview point refers to the point where the vehicle is on the target trajectory after Δt from the current time. Once the positions of the current point and the preview point are determined, the target motion trajectory can be obtained. Furthermore, the lateral position error and heading angle error can be calculated based on the target trajectory.

[0039] In some embodiments, the lateral position error refers to the lateral distance between the actual position of the vehicle's center of mass and the target trajectory, and the heading angle error refers to the deviation between the actual trajectory heading, i.e., the vehicle speed direction, and the target trajectory heading, i.e., the lane line direction.

[0040] Step 102 is to determine whether the vehicle is in a target driving state, where the target driving state includes at least one of: an error between the target trajectory and the actual trajectory of the vehicle is within a preset trajectory error range, a lateral position error is within a preset distance error range, and an error between the heading angle error and the rear wheel locking angle of the vehicle is within a preset angle error range.

[0041] In some embodiments, the error between the actual trajectory of the vehicle and the target trajectory can be determined by calculating the error between the actual position of the vehicle at the current time point and the ideal position on the target trajectory. When the error value is within a preset trajectory error range, the error is considered negligible, that is, the target trajectory is consistent with the actual trajectory of the vehicle. In actual application, the preset trajectory error range is adjusted according to vehicle parameters, historical trajectories in different application scenarios, motion status, etc.

[0042] In some embodiments, the method simulates the driver's adaptive adjustment of the steering wheel angle, and needs to keep the current vehicle speed direction consistent with the target trajectory heading (or lane line direction) to prevent the vehicle from deviating from the target trajectory. The error between the current vehicle speed direction and the target trajectory heading is the heading angle error, that is, the heading angle error is required to be the same as the rear wheel locking angle of the vehicle, and a certain error is allowed, that is, the lateral position error is within a preset angle error range. The preset angle error range can be adjusted according to the vehicle parameters in actual application, historical driving conditions, etc.

[0043] In some embodiments, the method simulates the driver's adaptive adjustment of the steering wheel angle, and needs to keep the vehicle's center of mass position on the target trajectory to prevent the vehicle from deviating from the target trajectory, that is, the lateral position error needs to be kept within a preset distance error range. The preset distance error range can be adjusted according to the vehicle parameters in actual application, historical driving conditions, etc.

[0044] Step 103 : In response to the vehicle not being in the target driving state, sending a steering wheel angle command to the front wheel steering actuator, wherein the steering wheel angle command is used to instruct the front wheel steering actuator to control the front wheels to perform a steering action according to the rear wheel locking angle.

[0045] In some embodiments, the method further includes: in the event of rear wheel steering failure, determining whether a position sensor of the rear wheel steering has failed; if the position sensor of the rear wheel steering has not failed, reading the rear wheel deadlock angle of the vehicle from the position sensor of the rear wheel steering system, or if the position sensor of the rear wheel steering system has failed, obtaining the rear wheel deadlock angle before the failure.

[0046] In some embodiments, when the rear wheel steering fails, the rear wheel steering failure causes the rear wheel to be stuck, and there is a fixed angle between the rear wheel and the forward direction of the vehicle, namely the rear wheel stuck angle. As the vehicle continues to move, when the front wheel steering remains unchanged, the target trajectory, lateral distance and heading angle of the vehicle will deviate from the target situation. In order to ensure the safety of the vehicle body, it is necessary to ensure that the actual trajectory of the vehicle does not deviate too much from the target trajectory or control the lateral distance error within a preset error range or control the heading angle error and the error of the rear wheel stuck angle within a preset angle error range.

[0047] In some embodiments, since the redundant front-wheel steering of L4 level autonomous driving is relatively mature, the front-wheel steering angle can be controlled to compensate for the rear-turn failure. This is achieved by controlling the front-wheel steering angle to be the same as the rear-turn deadlock angle. For example, the current rear-wheel deadlock angle is 45° to the right, that is, the current rear-wheel steering is 45° to the left of the target trajectory. At this time, the front-wheel steering angle is controlled to turn 45° to the left to ensure that the actual trajectory of the vehicle does not deviate too much from the target trajectory.

[0048] In some embodiments, due to the failure of rearward steering, it is impossible to obtain feedback on the compensation effect. Therefore, the present disclosure adds target trajectory, lateral position error and heading angle error interfaces to determine whether the vehicle is in the target driving state to realize feedback on the front wheel steering compensation effect, realize closed-loop control, and achieve the effect of manual driving.

[0049] Furthermore, in some embodiments, after sending the steering wheel angle command to the front-wheel steering actuator, the front-wheel steering actuator performs a steering action according to the rear wheel dead angle, and the actual driving trajectory of the vehicle changes. Specifically, the actual driving trajectory of the vehicle approaches the target driving trajectory, and the lateral distance error or heading angle error of the vehicle and the error of the rear wheel dead angle gradually decrease until the target driving state is reached, and compensation is stopped; otherwise, the current rear wheel dead angle will continue to be obtained, and the steering wheel angle command will be sent to the front-wheel steering actuator to control the front-wheel steering actuator to perform the steering action according to the current state.

[0050] It is understandable that due to changes in the actual trajectory of the vehicle, the error between the target trajectory and the actual trajectory, the lateral position error and the heading angle error will change in real time. The target trajectory, lateral position error and heading angle error interface of the vehicle are added to obtain the target trajectory, lateral position error and heading angle error interface of the vehicle in real time. When the deviation is too large, the front wheel steering compensation is performed to correct the vehicle's driving trajectory.

[0051] In summary, according to an embodiment of the present disclosure, when the rear-wheel steering fails, at least one of the target trajectory, lateral position error and heading angle error of the vehicle is obtained; whether the vehicle is in a target driving state is determined, wherein the target driving state includes at least one of: the error between the target trajectory and the actual trajectory of the vehicle is within a preset trajectory error range, the lateral position error is within a preset distance error range, and the error between the heading angle error and the rear wheel dead angle of the vehicle is within a preset angle error range; in response to the vehicle not being in the target driving state, a steering wheel angle command is sent to the front-wheel steering actuator, wherein the steering wheel angle command is used to instruct the front-wheel steering actuator to control the front wheels to perform steering actions according to the rear wheel dead angle. This solution performs front-wheel steering compensation when a single-point failure of the rear-wheel steering occurs, and performs compensation feedback based on the target trajectory, lateral position error and heading angle error to achieve a closed-loop control effect, so as to correct the vehicle's driving trajectory and realize the L4 autonomous driving safety requirements.

[0052] based on Figure 1 The embodiment shown, Figure 2 A flow chart of a vehicle body motion control method provided in an embodiment of the present disclosure is provided. As an example, the method can be applied to Figure 3 The body motion control architecture shown.

[0053] The method is applied to a vehicle, and its execution subject may be a main control chip of the vehicle. In some embodiments, the method execution subject may be a VMM in a vehicle body motion control architecture.

[0054] In some embodiments of the present disclosure, the present disclosure utilizes the relatively mature non-redundant rear-wheel steering of L2 level autonomous driving and the redundant front-wheel steering of L4 level autonomous driving, adds at least one of the target trajectory, lateral position error and heading angle error interfaces to the existing body motion control framework that integrates non-redundant rear-wheel steering and redundant front-wheel steering, and deploys the body motion control method of the present disclosure under this framework.

[0055] In some embodiments, Figure 3 A vehicle body motion control framework is provided, in which the vehicle body motion control method disclosed in the present invention can be applied and executed by the VMM, such as Figure 3 As shown in FIG, the architecture adds target trajectory, lateral position error, and heading angle error interfaces between the Advanced Driver Assistance Systems (ADAS) and the VMM. Thus, the VMM can obtain the vehicle's current target trajectory, lateral position error, and heading angle error in real time through these interfaces.

[0056] Under normal autonomous driving conditions, ADAS sends target steering wheel angle and target rear wheel angle control commands to the VMM. The VMM transparently transmits the control command signals to the front wheel steering actuator (Electric Power Steering, EPS) and the VDM integrated in the vehicle control unit (Vehicle Control Unit, XCU). At the same time, the VDM converts the target rear wheel angle into a target rack position request signal after calculation, and sends the rack position signal to the rear steering actuator RWS. The VDM provides real-time feedback of the current rear wheel angle and rear wheel actuator status to the VMM.

[0057] In the event of rear wheel steering failure, the VMM executes the vehicle body motion control method of the present disclosure.

[0058] The method includes the following steps 201-206.

[0059] Step 201 : When rear wheel steering fails, obtain at least one of a target trajectory, a lateral position error, and a heading angle error of the vehicle.

[0060] In some embodiments, rear-wheel steering failure includes: failure to receive the actual rack position and / or rear-wheel actuator status sent by the vehicle dynamic control system within a preset feedback time, or abnormality in the received actual rack position and / or rear-wheel actuator status.

[0061] In some embodiments, the abnormality of the actual rack position received includes that the sensor inside the actuator may malfunction, resulting in the inability to accurately sense the rack position, thereby sending abnormal data, or the mechanical components such as the rack or gear inside the actuator may be damaged or worn, resulting in the rack position being unable to move normally or producing an abnormal position, etc.; the abnormality of the rear-rotation actuator status includes problems in the communication between the actuator and the control system, resulting in the inability to accurately transmit or analyze the status information, resulting in an abnormal status, or the mechanical structure inside the actuator is damaged or stuck, resulting in failure to operate normally or the sensor being unable to read accurate status information, etc.

[0062] In some embodiments, as Figure 4 As shown, obtaining the target trajectory of the vehicle includes the following steps 301-303.

[0063] Step 301: Acquire the actual position of the vehicle at a first moment from a vehicle position sensor, where the first moment is the current moment.

[0064] In some embodiments, the actual position information of the vehicle, including the vehicle position coordinates, heading angle, yaw angle, pitch angle, roll angle and other information, is obtained through at least one of a global positioning system (GPS), an inertial measurement unit, a visual sensor, and a radar sensor.

[0065] In some embodiments, the position coordinate information refers to the horizontal and vertical coordinate information of the relative position of a certain point on the vehicle's driving trajectory relative to a designated point (eg, the center of a circle in which the vehicle makes circular motion).

[0066] Step 302: Obtain the preview position of the vehicle at a second moment, where the second moment is the moment after adding a preset time to the current moment.

[0067] Step 303: Acquire the target trajectory of the vehicle based on the actual position at the first moment and the preview position at the second moment.

[0068] In some embodiments, obtaining the preview position of the vehicle at the second moment includes: determining the preview position of the vehicle at the second moment through a preset preview model, or fitting a relationship curve between time and preview position based on at least one of vehicle parameters, historical trajectories of the vehicle in different application scenarios, and the motion state of the vehicle, and determining the preview position of the vehicle at the second moment from the relationship curve.

[0069] In some embodiments, as Figure 6 As shown in the figure, it shows a trajectory of a rear-wheel steering vehicle when turning. The vehicle's automatic driving module will generate a target trajectory MQ1 based on the surrounding environmental information. Due to various interference factors, the vehicle's actual driving trajectory MQ2 will deviate from the ideal target trajectory. Among them, A is the ideal position at the current moment, A' is the actual position at the current moment, and point B is the preview point. Point B is the position point of the vehicle on the target trajectory Δt time after the current moment t.

[0070] In some embodiments, the vehicle's current location can be acquired using high-precision GPS. Preview point B can be obtained using several methods: calculations based on existing preview models, or by fitting a time-preview point relationship curve based on multiple parameters, such as vehicle parameters, historical trajectories in different application scenarios, and motion state. Once the current and preview points are determined, the target trajectory can be acquired.

[0071] In some embodiments, as Figure 5 As shown, obtaining the lateral position error and heading angle error of the vehicle includes the following steps 401 and 402 .

[0072] Step 401: Acquire the actual trajectory of the vehicle from the vehicle position sensor.

[0073] In some embodiments, the actual position information of the vehicle is obtained through at least one of a global positioning system, an inertial measurement unit, a visual sensor, and a radar sensor, and the actual trajectory of the vehicle can be obtained based on the actual position information of the vehicle.

[0074] Step 402 : Calculate the coordinate difference between the vehicle's position on the actual trajectory and the vehicle's position on the target trajectory to determine the vehicle's lateral position error and heading angle error.

[0075] In some embodiments, the coordinates of any point on the target trajectory are obtained, and the current vehicle position coordinates are obtained from a sensor that obtains vehicle position information, such as GPS. The difference between these two coordinates can be calculated to obtain the lateral position error and the heading angle error.

[0076] In some embodiments, as Figure 7 As shown in the figure, the failure of rear wheel steering causes the rear wheels to get stuck. There is a fixed angle between the rear wheels and the vehicle's forward direction, which is the rear wheel stuck angle. As the vehicle continues to move, with the front wheel steering unchanged, the vehicle's target trajectory, lateral distance, and heading angle will deviate from the target, resulting in lateral position error and heading angle error.

[0077] In some embodiments, the lateral position error is the lateral distance between the actual position of the vehicle's center of mass and the target trajectory, which is obtained by establishing a coordinate system to depict the position coordinates of the vehicle's center of mass and the target trajectory curve and calculating the coordinate difference.

[0078] In some embodiments, the heading angle error is the deviation between the actual trajectory heading, i.e., the vehicle speed direction, and the target trajectory heading, i.e., the lane line direction, and is obtained by establishing a coordinate system and calculating the difference between the actual trajectory tangent slope and the target trajectory tangent slope.

[0079] Step 202: Determine whether the rear wheel steering position sensor is faulty.

[0080] Step 203: If the position sensor of the rear wheel steering system is not invalid, read the rear wheel locking angle of the vehicle from the position sensor of the rear wheel steering system.

[0081] In some embodiments, after determining whether the position sensor of the rear wheel steering system has failed, the method further includes: if the position sensor of the rear wheel steering system has failed, obtaining the rear wheel stuck angle before the failure.

[0082] In an embodiment of the present disclosure, the rear wheel deadlock angle may be read from the RWS position sensor. If the sensor fails, the value before the failure is defaulted.

[0083] Step 204 is to determine whether the vehicle is in a target driving state, where the target driving state includes at least one of: an error between the target trajectory and the actual trajectory of the vehicle is within a preset trajectory error range, a lateral position error is within a preset distance error range, and an error between the heading angle error and the rear wheel locking angle of the vehicle is within a preset angle error range.

[0084] In some embodiments, the error between the target trajectory and the actual trajectory of the vehicle can be determined by at least one of Euclidean distance, root mean square error, curve fitting, and dynamic time warping.

[0085] In some embodiments, the trajectory error range, distance error range, and angle error range can be pre-set based on vehicle parameters, vehicle operating status, etc., with the principle of ensuring that the autonomous driving safety requirements are met within the trajectory error range.

[0086] It should be understood that the judgment of the target driving state is to feedback the front wheel steering compensation effect, so that the rear turn failure compensation algorithm can achieve the effect of manual driving. The effect of manual driving is that the driver will adaptively adjust the steering wheel angle according to the vehicle's driving direction and vehicle position, keep the vehicle speed direction consistent with the lane line direction, keep the vehicle's center of mass position on the target trajectory, there is a heading angle deviation between the head direction and the target trajectory heading, and the rear wheel stuck angle, front wheel compensation angle and heading angle deviation angle are the same.

[0087] Step 205 : In response to the vehicle not being in the target driving state, sending a steering wheel angle command.

[0088] Step 206: Transmit the steering wheel angle command to the front wheel steering actuator.

[0089] In some embodiments, as Figure 3 As shown, ADAS sends a steering wheel angle control command to the VMM, and the VMM transmits the control command signal to the front wheel steering gear through a transparent transmission, so that the steering wheel angle is turned according to a certain transmission ratio, and the front wheels perform steering actions according to the rear turn lock angle.

[0090] It is understandable that due to changes in the actual trajectory of the vehicle, the error between the target trajectory and the actual trajectory, the lateral position error and the heading angle error will change in real time. The present disclosure adds a target trajectory, lateral position error and heading angle error interface for the vehicle to obtain the target trajectory, lateral position error and heading angle error interface for the vehicle in real time. When the deviation is too large, front wheel steering compensation is performed to correct the vehicle's driving trajectory.

[0091] In some embodiments, as Figure 3As shown, when a single-point steering failure occurs in the rear turn, the VDM cannot feed back the current rear wheel angle and the rear turn actuator status to the VMM, and the communication fails. At this time, the VMM implements the rear turn failure compensation algorithm. The logic of the rear turn compensation algorithm is the method disclosed in the present invention, so that the steering angle executed by the front wheel is equal to the rear turn dead angle, and the front wheel steering angle is closed-loop controlled according to the target trajectory, lateral position error, and heading angle error to ensure that the lateral distance error is within the target range and the heading angle error is controlled near the rear wheel dead angle. Even if the communication fails, it can ensure that the target heading angle does not deviate too much, avoiding vehicle instability, so that the driver has time to control the vehicle to execute pull-over parking, and can help the vehicle to achieve safe pull-over parking.

[0092] In summary, according to the embodiments of the present disclosure, on the basis of utilizing the relatively mature non-redundant rear-wheel steering of L2 level autonomous driving and the redundant front-wheel steering of L4 level autonomous driving, target trajectory, lateral distance error and heading angle error interfaces are added. When the vehicle is autonomously driving, if a single-point failure occurs in the rear-wheel steering, the vehicle can perform closed-loop control of the front-wheel steering angle according to the target trajectory, lateral position error, and heading angle error to achieve rear-wheel failure compensation, ensure that the lateral distance error is within the target range, and control the heading angle error near the rear wheel dead angle. Even if the communication fails, it can ensure that the target heading angle does not deviate too much, avoid vehicle instability, resolve safety hazards, and help the vehicle park safely on the side of the road, realizing the safety requirements of L4 autonomous driving.

[0093] Corresponding to the above-mentioned vehicle body motion control method, the present disclosure also proposes a vehicle body motion control device. Figure 8 FIG. 5 is a structural diagram of a vehicle body motion control device 500 provided in an embodiment of the present disclosure. Figure 8 As shown, including:

[0094] An acquisition unit 510 is used to acquire at least one of the target trajectory, lateral position error, and heading angle error of the vehicle when the rear-wheel steering fails; a judgment unit 520 is used to judge whether the vehicle is in a target driving state, wherein the target driving state includes at least one of: an error between the target trajectory and the actual trajectory of the vehicle is within a preset trajectory error range, a lateral position error is within a preset distance error range, and an error between the heading angle error and the rear wheel dead angle of the vehicle is within a preset angle error range; a compensation unit 530 is used to send a steering wheel angle command to the front-wheel steering actuator in response to the vehicle not being in the target driving state, wherein the steering wheel angle command is used to instruct the front-wheel steering actuator to control the front wheels to perform steering action according to the rear wheel dead angle.

[0095] In some embodiments, the rear wheel steering failure includes: any one of the following: the actual rack position and / or rear wheel actuator status not being received from the RWS feedback within a preset feedback time, or the actual rack position and / or rear wheel actuator status being received being abnormal.

[0096] In some embodiments, the judgment unit 520 is also used to: in the event of a rear-wheel steering failure, determine whether the position sensor of the rear-wheel steering has failed; if the position sensor of the rear-wheel steering has not failed, read the rear wheel deadlock angle of the vehicle from the position sensor of the rear-wheel steering system, or if the position sensor of the rear-wheel steering system has failed, obtain the rear wheel deadlock angle before the failure.

[0097] In some embodiments, the acquisition unit 510 is specifically used to: obtain the actual position of the vehicle at the first moment from the vehicle position sensor, where the first moment is the current moment; obtain the preview position of the vehicle at the second moment, where the second moment is the moment after the current moment plus a preset time; and obtain the target trajectory of the vehicle based on the actual position at the first moment and the preview position at the second moment.

[0098] In some embodiments, the acquisition unit 510 is specifically used to: determine the preview position of the vehicle at the second moment through a preset preview model, or, based on at least one of the vehicle parameters, the historical trajectory of the vehicle in different application scenarios, and the motion state of the vehicle, fit a relationship curve between time and preview position, and determine the preview position of the vehicle at the second moment from the relationship curve.

[0099] In some embodiments, the acquisition unit 510 is further used to: acquire the actual trajectory of the vehicle from the vehicle position sensor; calculate the coordinate difference between the vehicle's position on the actual trajectory and the vehicle's position on the target trajectory to determine the vehicle's lateral position error and heading angle error.

[0100] In summary, according to the embodiments of the present disclosure, the device performs front wheel steering compensation when a single-point failure occurs in the rear wheel steering through an acquisition unit, a judgment unit, and a compensation unit, and performs compensation feedback based on the target trajectory, lateral position error, and heading angle error, thereby achieving a closed-loop control effect, correcting the vehicle's driving trajectory, and realizing L4 autonomous driving safety requirements.

[0101] It should be noted that since the device embodiment of the present disclosure corresponds to the above-mentioned method embodiment, the above-mentioned explanation of the method embodiment is also applicable to the device of this embodiment, and the principles are the same. For details not disclosed in the device embodiment, reference can be made to the above-mentioned method embodiment, and they will not be repeated in this disclosure.

[0102] According to an embodiment of the present disclosure, the present disclosure also provides an electronic device, a readable storage medium, and a computer program product.

[0103] Figure 9 A schematic block diagram of an example electronic device 600 that can be used to implement embodiments of the present disclosure is shown. The electronic device is intended to represent various forms of digital computers, such as laptop computers, desktop computers, workstations, personal digital assistants, servers, blade servers, mainframe computers, and other suitable computers. The electronic device can also represent various forms of mobile devices, such as personal digital assistants, cellular phones, smartphones, wearable devices, and other similar computing devices. The components shown herein, their connections and relationships, and their functions are provided as examples only and are not intended to limit the implementation of the present disclosure described and / or claimed herein.

[0104] like Figure 9 As shown, the device 600 includes a computing unit 601, which can perform various appropriate actions and processes according to a computer program stored in a ROM (Read-Only Memory) 602 or a computer program loaded from a storage unit 608 into a RAM (Random Access Memory) 603. Various programs and data required for the operation of the device 600 can also be stored in the RAM 603. The computing unit 601, the ROM 602, and the RAM 603 are connected to each other via a bus 604. An I / O (Input / Output) interface 605 is also connected to the bus 604.

[0105] Various components in device 600 are connected to I / O interface 605, including an input unit 606, such as a keyboard, mouse, etc.; an output unit 607, such as various types of displays, speakers, etc.; a storage unit 608, such as a magnetic disk, optical disk, etc.; and a communication unit 609, such as a network card, modem, wireless communication transceiver, etc. The communication unit 609 allows device 600 to exchange information / data with other devices via a computer network such as the Internet and / or various telecommunication networks.

[0106] Computing unit 601 can be any general-purpose and / or specialized processing component with processing and computing capabilities. Some examples of computing unit 601 include, but are not limited to, a CPU (Central Processing Unit), a GPU (Graphic Processing Unit), various specialized AI (Artificial Intelligence) computing chips, various computing units that run machine learning model algorithms, a DSP (Digital Signal Processor), and any suitable processor, controller, microcontroller, etc. Computing unit 601 performs the various methods and processes described above, such as the vehicle body motion control method. For example, in some embodiments, the vehicle body motion control method can be implemented as a computer software program tangibly embodied in a machine-readable medium, such as storage unit 608. In some embodiments, part or all of the computer program can be loaded and / or installed onto device 600 via ROM 602 and / or communication unit 609. When the computer program is loaded into RAM 603 and executed by computing unit 601, one or more steps of the method described above can be performed. Alternatively, in other embodiments, the computing unit 601 may be configured to execute the aforementioned vehicle body motion control method in any other appropriate manner (for example, by means of firmware).

[0107] Various embodiments of the systems and techniques described herein can be implemented in digital electronic circuit systems, integrated circuit systems, FPGAs (Field Programmable Gate Arrays), ASICs (Application-Specific Integrated Circuits), ASSPs (Application-Specific Standard Products), SOCs (System on Chips), CPLDs (Complex Programmable Logic Devices), computer hardware, firmware, software, and / or combinations thereof. These various embodiments can include being implemented in one or more computer programs that are executable and / or interpreted on a programmable system that includes at least one programmable processor, which can be a special-purpose or general-purpose programmable processor that can receive data and instructions from a storage system, at least one input device, and at least one output device, and transmit data and instructions to the storage system, the at least one input device, and the at least one output device.

[0108] The program code for implementing the method of the present disclosure can be written in any combination of one or more programming languages. These program codes can be provided to a processor or controller of a general-purpose computer, a special-purpose computer, or other programmable data processing device so that when the program code is executed by the processor or controller, the functions / operations specified in the flow chart and / or block diagram are implemented. The program code can be executed entirely on the machine, partially on the machine, as a stand-alone software package, partially on the machine and partially on a remote machine, or entirely on a remote machine or server.

[0109] In the context of the present disclosure, a machine-readable medium may be a tangible medium that may contain or store a program for use by or in conjunction with an instruction execution system, device, or apparatus. A machine-readable medium may be a machine-readable signal medium or a machine-readable storage medium. A machine-readable medium may include, but is not limited to, an electronic, magnetic, optical, electromagnetic, infrared, or semiconductor system, device, or apparatus, or any suitable combination of the foregoing. More specific examples of machine-readable storage media may include an electrical connection based on one or more wires, a portable computer disk, a hard disk, RAM, ROM, EPROM (Electrically Programmable Read-Only-Memory) or flash memory, optical fiber, CD-ROM (Compact Disc Read-Only Memory), an optical storage device, a magnetic storage device, or any suitable combination of the foregoing.

[0110] To provide interaction with a user, the systems and techniques described herein can be implemented on a computer having: a display device (e.g., a CRT (Cathode-Ray Tube) or LCD (Liquid Crystal Display) monitor) for displaying information to the user; and a keyboard and pointing device (e.g., a mouse or trackball) through which the user can provide input to the computer. Other types of devices can also be used to provide interaction with the user; for example, the feedback provided to the user can be any form of sensory feedback (e.g., visual feedback, auditory feedback, or tactile feedback); and input from the user can be received in any form (including acoustic input, voice input, or tactile input).

[0111] The systems and techniques described herein can be implemented in a computing system that includes backend components (e.g., as a data server), or a computing system that includes middleware components (e.g., an application server), or a computing system that includes frontend components (e.g., a user computer with a graphical user interface or web browser through which a user can interact with implementations of the systems and techniques described herein), or a computing system that includes any combination of such backend components, middleware components, or frontend components. The components of the system can be interconnected by any form or medium of digital data communication (e.g., a communication network). Examples of communication networks include: LAN (Local Area Network), WAN (Wide Area Network), the Internet, and blockchain networks.

[0112] A computer system may include a client and a server. The client and server are generally remote from each other and typically interact via a communication network. This client-server relationship is established by computer programs running on the respective computers, establishing a client-server relationship. The server may be a cloud server, also known as a cloud computing server or cloud host, a host product within the cloud computing service ecosystem that addresses the management difficulties and limited scalability of traditional physical hosts and VPS services ("Virtual Private Servers" or simply "VPS"). The server may also be a server in a distributed system or a server integrated with blockchain.

[0113] It's important to note that artificial intelligence (AI) is the study of how computers can simulate certain human thought processes and intelligent behaviors (such as learning, reasoning, thinking, and planning). This encompasses both hardware and software technologies. AI hardware technologies generally include sensors, specialized AI chips, cloud computing, distributed storage, and big data processing. AI software technologies primarily encompass computer vision, speech recognition, natural language processing, machine learning / deep learning, big data processing, and knowledge graphs.

[0114] It should be understood that the various forms of processes shown above can be used to reorder, add or delete steps. For example, the steps recorded in this disclosure can be executed in parallel, sequentially or in a different order, as long as the desired results of the technical solutions disclosed in this disclosure can be achieved, and this document does not limit them here. The above specific implementation methods do not constitute limitations on the scope of protection of this disclosure. It should be understood by those skilled in the art that various modifications, combinations, sub-combinations and substitutions can be made according to design requirements and other factors. Any modifications, equivalent substitutions and improvements made within the spirit and principles of this disclosure should be included in the scope of protection of this disclosure.

Claims

1. A vehicle body motion control method, characterized in that: The method comprises: In the event of a rear wheel steering failure, obtaining at least one of a target trajectory, a lateral position error, and a heading angle error of the vehicle; Determining whether the vehicle is in a target driving state, wherein the target driving state includes at least one of: an error between the target trajectory and the actual trajectory of the vehicle is within a preset trajectory error range, a lateral position error is within a preset distance error range, and an error between the heading angle error and the rear wheel locking angle of the vehicle is within a preset angle error range; In response to the vehicle not being in the target driving state, a steering wheel angle command is sent to the front wheel steering actuator, wherein the steering wheel angle command is used to instruct the front wheel steering actuator to control the front wheels to perform a steering action according to the rear wheel locking angle.

2. The method according to claim 1, characterized in that The rear wheel steering failure includes: the actual rack position and / or the rear wheel steering actuator state is not received within a preset feedback time, and the received actual rack position and / or the rear wheel steering actuator state is abnormal.

3. The method according to claim 1 or 2, characterized in that The method further comprises: In the case of rear wheel steering failure, determining whether the rear wheel steering position sensor is failed; If the position sensor of the rear wheel steering system is not invalid, the rear wheel stuck angle of the vehicle is read from the position sensor of the rear wheel steering system, or If the position sensor of the rear wheel steering system fails, the rear wheel stuck angle before the failure is obtained.

4. The method according to claim 1, wherein The obtaining of the target trajectory of the vehicle comprises: obtaining an actual position of the vehicle at a first moment from a vehicle position sensor, where the first moment is the current moment; Obtaining a preview position of the vehicle at a second moment, where the second moment is a moment after adding a preset time to the current moment; A target trajectory of the vehicle is obtained according to the actual position at the first moment and the preview position at the second moment.

5. The method according to claim 3, characterized in that The obtaining of the preview position of the vehicle at the second moment comprises: Determine the preview position of the vehicle at the second moment by using a preset preview model, or, A relationship curve between time and preview position is fitted based on at least one of the vehicle parameters, the historical trajectory of the vehicle in different application scenarios, and the motion state of the vehicle, and the preview position of the vehicle at the second moment is determined based on the relationship curve.

6. The method according to claim 1, characterized in that The obtaining of the lateral position error and heading angle error of the vehicle comprises: Obtaining the actual trajectory of the vehicle from the vehicle position sensor; The coordinate difference between the position of the vehicle on the actual track and the position on the target track is calculated to determine the lateral position error and the heading angle error of the vehicle.

7. A vehicle body motion control device, characterized in that: The device comprises: an acquisition unit, configured to acquire at least one of a target trajectory, a lateral position error, and a heading angle error of the vehicle when the rear wheel steering fails; a determination unit, configured to determine whether the vehicle is in a target driving state, wherein the target driving state includes at least one of: an error between the target trajectory and the actual trajectory of the vehicle is within a preset trajectory error range, the lateral position error is within a preset distance error range, and an error between the heading angle error and the rear wheel locking angle of the vehicle is within a preset angle error range; The compensation unit is configured to send a steering wheel angle command to a front wheel steering actuator in response to the vehicle not being in a target driving state, wherein the steering wheel angle command is configured to instruct the front wheel steering actuator to control the front wheels to perform a steering action according to a rear wheel deadlock angle.

8. An electronic device comprising: at least one processor; as well as a memory communicatively connected to the at least one processor; wherein, The memory stores instructions that can be executed by the at least one processor, and the instructions are executed by the at least one processor to enable the at least one processor to perform the method according to any one of claims 1 to 6.

9. A non-transitory computer-readable storage medium storing computer instructions, wherein: The computer instructions are used to cause the computer to execute the method according to any one of claims 1 to 6.

10. A computer program product comprising a computer program, which, when executed by a processor, implements the method according to any one of claims 1 to 6.

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