Steering wheel angle calculation method, device, equipment and readable storage medium

Abstract

The present application provides a steering wheel angle calculation method, apparatus, device, and readable storage medium. When a target vehicle's driving direction shifts laterally, the steering wheel angle calculation method provided in an embodiment of the present application can determine a first steering wheel angle of the target vehicle at the target vehicle's control terminal. After determining the first steering wheel angle, the method can perform a compensation calculation on the first steering wheel angle based on a preset reverse stretch rate to obtain a target steering wheel angle for the target vehicle. The steering wheel angle calculation method provided in an embodiment of the present application can help reduce the error between the steering wheel angle of a vehicle's lateral movement and the steering wheel angle required to track the vehicle's self-planned desired driving trajectory, effectively reducing the deviation between the vehicle's current driving trajectory and the vehicle's self-planned desired driving trajectory, and improving the accuracy of vehicle driving.

Description

Technical Field

[0001] The present application relates to the field of autonomous driving technology, and in particular to a method, device, equipment and readable storage medium for calculating a steering wheel angle. Background Art

[0002] With the development of science and technology, autonomous driving technology has also gradually developed. In actual application, the vehicle performing the autonomous driving task can automatically plan a desired driving trajectory route based on the current driving environment and surrounding information. At the same time, the steering wheel angle can be adjusted in time based on the current driving trajectory route of the vehicle currently performing the autonomous driving task, so that the current driving trajectory route of the vehicle currently performing the autonomous driving task does not deviate too much from the desired driving trajectory route planned by the vehicle itself, thereby ensuring that the vehicle performing the autonomous driving task can travel according to the desired driving trajectory route planned by itself. Therefore, when the current driving trajectory route of the vehicle performing the autonomous driving task deviates from the desired driving trajectory route planned by the vehicle itself, the vehicle's steering wheel can correct the vehicle's driving direction by adjusting the steering wheel angle.

[0003] As the angle between the vehicle and the reference line along which the vehicle is traveling increases, the error in the vehicle's steering wheel angle calculated using the linear model also increases. Consequently, the error between the steering wheel angle calculated using the linear model and the steering wheel angle required to track the vehicle's self-planned desired driving trajectory becomes larger. Summary of the Invention

[0004] The present application aims to solve at least one of the above-mentioned technical defects. In view of this, the present application provides a steering wheel angle calculation method, device, equipment and readable storage medium for solving the technical defect of large error in determining the steering wheel angle of the vehicle in the prior art.

[0005] A method for calculating a steering wheel angle, comprising:

[0006] When the target vehicle's driving direction moves laterally, determining a first direction wheel turning angle of the target vehicle at a control terminal of the target vehicle;

[0007] Based on a preset reverse stretching rate, a compensation calculation is performed on the first direction wheel turning angle to obtain a target direction wheel turning angle of the target vehicle.

[0008] Preferably, the step of calculating the reverse stretching rate includes:

[0009] Decomposing the target vehicle's speed at the center of gravity projection point to obtain a nonlinear speed component and a linear speed component at the center of gravity;

[0010] The nonlinear velocity component at the center of gravity is simulated into a center of gravity circular trajectory, and the linear velocity component is simulated into a center of gravity elliptical trajectory, and the positive stretching rate of the center of gravity circular trajectory to the center of gravity elliptical trajectory is solved;

[0011] The reverse stretching ratio is obtained according to the forward stretching ratio.

[0012] Preferably, the step of performing compensation calculation on the first direction wheel turning angle to obtain the target direction wheel turning angle of the target vehicle includes:

[0013] Decomposing the target vehicle's travel speed at the non-directional wheel to obtain a non-directional wheel linear velocity component;

[0014] Correcting the linear trajectory represented by the non-directional wheel linear velocity component using the reverse stretching rate, and constructing a conversion relationship between the first directional wheel angle, the reverse stretching rate, and the target directional wheel angle;

[0015] The target direction wheel turning angle of the target vehicle is calculated according to the conversion relationship.

[0016] Preferably, the center of gravity projection point is the projection point of the center of gravity of the target vehicle on the road on which it is traveling;

[0017] The linear velocity component at the center of gravity includes a first velocity of the target vehicle along a tangent direction of the road and a second velocity along a normal direction of the road;

[0018] The nonlinear velocity component at the center of gravity includes a third velocity of the target vehicle along the tangent direction of the road and a fourth velocity along the normal direction of the road.

[0019] Preferably, the step of simulating the nonlinear velocity component at the center of gravity into a circular trajectory of the center of gravity, simulating the linear velocity component into an elliptical trajectory of the center of gravity, and solving the forward stretching rate of the transformation of the circular trajectory of the center of gravity into the elliptical trajectory of the center of gravity includes:

[0020] Comparing the first rate and the third rate to obtain a first stretching ratio;

[0021] Comparing the second rate and the fourth rate to obtain a second stretching ratio;

[0022] The first stretching ratio and the second stretching ratio are substituted into the ellipse curvature formula to obtain the forward stretching ratio.

[0023] Preferably, the step of determining the first direction wheel turning angle of the target vehicle includes:

[0024] Obtaining the real-time speed of the target vehicle;

[0025] Determine the real-time rotation radius of the non-directional wheel of the target vehicle using a preset linear model according to the real-time speed;

[0026] The first steering wheel rotation angle is calculated by using the real-time rotation radius of the non-steering wheel and obtaining the distance between the midpoint of the steering wheel axis and the midpoint of the non-steering wheel axis of the target vehicle.

[0027] Preferably, determining whether the target vehicle's driving direction has moved laterally includes:

[0028] Determining a first angle between the body orientation of the target vehicle and the road direction;

[0029] Determining whether the first angle is greater than a preset first threshold;

[0030] If the first angle is greater than the first threshold, it is determined that the driving direction of the target vehicle has moved laterally.

[0031] Preferably, the preset first threshold has a value range of [0°, 20°].

[0032] A device for calculating a steering wheel angle, comprising:

[0033] a first calculation unit, configured to determine a first direction wheel turning angle of the target vehicle at a control terminal of the target vehicle when the target vehicle's driving direction moves laterally;

[0034] The second calculation unit is configured to perform compensation calculation on the first direction wheel turning angle based on a preset reverse stretching rate to obtain a target direction wheel turning angle of the target vehicle.

[0035] A steering wheel angle calculation device includes: one or more processors, and a memory;

[0036] The memory stores computer-readable instructions, wherein when the computer-readable instructions are executed by the one or more processors, the steps of the steering wheel angle calculation method as described in any one of the above descriptions are implemented.

[0037] A readable storage medium stores computer-readable instructions. When the computer-readable instructions are executed by one or more processors, the one or more processors implement the steps of the steering wheel angle calculation method as described in any one of the above descriptions.

[0038] As can be seen from the technical solutions described above, when the target vehicle's driving direction moves laterally, the steering wheel angle calculation method provided in the embodiment of the present application can determine the target vehicle's first steering wheel angle at the control terminal of the target vehicle; after determining the first steering wheel angle, the first steering wheel angle can be compensated based on a preset reverse stretching rate to obtain the target steering wheel angle of the target vehicle. The steering wheel angle calculation method provided in the embodiment of the present application can help reduce the error between the steering wheel angle of the vehicle's lateral movement and the steering wheel angle required to track the vehicle's self-planned desired driving trajectory, effectively reducing the deviation between the vehicle's current driving trajectory and the vehicle's self-planned desired driving trajectory, and improving the accuracy of vehicle driving. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative labor.

[0040] Figure 1 Schematic diagram comparing three driving effects of a vehicle performing a driving task provided in an embodiment of the present application

[0041] Figure 2 A flowchart of a method for calculating a steering wheel angle provided in an embodiment of the present application;

[0042] Figure 3 A schematic diagram showing the effect of analyzing the instantaneous motion trajectory of a vehicle using a linearization method according to an embodiment of the present application;

[0043] Figure 4 A schematic diagram showing the effect of analyzing the instantaneous motion trajectory of a vehicle using a nonlinear method according to an embodiment of the present application;

[0044] Figure 5 This is a schematic diagram of the structure of a steering wheel angle calculation device according to an embodiment of the present application;

[0045] Figure 6 This is a hardware structure block diagram of a steering wheel angle calculation device disclosed in an embodiment of the present application. DETAILED DESCRIPTION

[0046] The following will be combined with the drawings in the embodiments of this application to clearly and completely describe the technical solutions in the embodiments of this application. Obviously, the embodiments described are only part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.

[0047] In practical applications, a nonlinear analysis of the vehicle's immediate driving trajectory based on kinematic equations is typically performed to determine the vehicle's forward velocity, which is then used to calculate the steering angle required for lateral motion. However, this nonlinear analysis method is computationally intensive and cannot quickly determine the required steering angle. In practical applications, the calculation of the steering angle for lateral motion must be timely, requiring rapid calculation of the required steering angle. Therefore, some have considered performing an approximate nonlinear analysis, treating the vehicle's immediate steering wheel trajectory as a circle. Based on this, a kinematic linearization analysis of the vehicle's immediate motion can quickly determine the required steering angle. However, the steering angle obtained through linearization often exhibits significant errors, which can easily cause the vehicle to deviate from its intended driving trajectory.

[0048] For example, Figure 1 As shown, Figure 1 A schematic diagram comparing three driving effects of a vehicle performing a driving task is shown as an example.

[0049] exist Figure 1 In the figure, the rectangular box represents the obstacles that the vehicle needs to avoid during driving, and the dotted curve represents the expected trajectory of the vehicle performing the driving task.

[0050] As shown in the effect diagram (b), if the steering wheel angle required for the vehicle to perform lateral movement obtained by linearization analysis is directly used as the steering wheel angle for adjusting the driving direction of the vehicle performing the driving task, it can be found by following the driving trajectory of the vehicle performing the driving task that as the vehicle travels, the vehicle gradually deviates from the expected driving trajectory of the vehicle.

[0051] As shown in the effect diagram (c), if a steering wheel angle compensation angle is added to the steering wheel angle required for lateral movement of the vehicle obtained by linearization analysis and then used as the steering wheel angle for adjusting the driving direction of the vehicle performing the driving task, it can be found by following the driving trajectory of the vehicle performing the driving task that as the vehicle travels, the vehicle can travel according to the desired driving trajectory.

[0052] From this we can see that it is necessary to perform compensation calculation on the vehicle's steering wheel angle obtained by linear analysis.

[0053] Given that most of the current steering wheel angle calculation schemes are difficult to adapt to complex and changeable business data, the applicant has studied a steering wheel angle calculation scheme. This calculation method can compensate for the first steering wheel angle of the target vehicle determined at the control terminal of the target vehicle to obtain the steering wheel angle of the vehicle for lateral movement, which is conducive to ensuring that the vehicle can travel according to the preset driving trajectory route.

[0054] The present application can be applied to any device that can calculate the steering wheel angle. Optionally, the device that can calculate the steering wheel angle can be a vehicle-mounted computing terminal, or a terminal with data processing capabilities such as a tablet computer or mobile phone with sufficiently powerful computing power.

[0055] The following combination Figure 2 , introduces the process of the steering wheel angle calculation method given in the embodiment of the present application, which may include the following steps:

[0056] Step S101: When the target vehicle moves laterally in its driving direction, a first direction wheel turning angle of the target vehicle is determined at a control terminal of the target vehicle.

[0057] Specifically, when the target vehicle's driving direction shifts laterally during vehicle travel, different steering wheel angles are required to adjust the direction. Therefore, in the method provided in the embodiment of the present application, a control terminal of the target vehicle determines a first steering wheel angle of the target vehicle, so that a target steering wheel angle can be determined based on the first steering wheel angle.

[0058] For example, in order to ensure calculation timeliness, the method provided in the embodiment of the present application can use linearization analysis to obtain the steering wheel angle required for the vehicle to perform the driving task when performing lateral movement.

[0059] For example, a preset linear model may be used to calculate the steering wheel angle required for a vehicle to perform a driving task when performing lateral movement.

[0060] Step S102 : performing compensation calculation on the first direction wheel turning angle based on a preset reverse stretching rate to obtain a target direction wheel turning angle of the target vehicle.

[0061] Specifically, from the above introduction, it can be seen that the method provided in the embodiment of the present application can use linearization analysis to obtain the steering wheel turning angle required for the vehicle performing the driving task when performing lateral movement. From the above introduction, it can be seen that the steering wheel turning angle of the vehicle performing lateral movement obtained by linearization analysis often has a relatively large error, which can easily cause the vehicle to deviate from the predetermined driving trajectory.

[0062] In order to reduce the error in the steering wheel angle, the steering wheel angle required for the lateral movement of the vehicle performing the driving task obtained through linearization analysis can be angle compensated, and then the second steering wheel angle obtained after the angle compensation can be used as the target steering wheel angle required for the lateral movement of the vehicle performing the driving task.

[0063] Since the first directional wheel turning angle is calculated using the on-board computing terminal based on a simplified calculation model, according to experiments, there is an error in the first directional wheel turning angle calculated using the on-board computing terminal based on the simplified calculation model. It is necessary to use a preset reverse stretching rate to correct the error of the first directional wheel turning angle so that a more accurate directional wheel turning angle can be obtained.

[0064] Therefore, in order to further determine the target direction wheel turning angle required for the vehicle performing the driving task when performing lateral movement, after determining the first direction wheel turning angle of the target vehicle, the first direction wheel turning angle can be further compensated based on the preset reverse stretching rate so that the target direction wheel turning angle of the target vehicle can be obtained.

[0065] As can be seen from the technical solutions described above, when the target vehicle's driving direction shifts laterally, the steering wheel angle calculation method provided in the embodiment of the present application can determine the target vehicle's first steering wheel angle at the target vehicle's control terminal; after determining the first steering wheel angle, the first steering wheel angle can be compensated based on a preset reverse stretching rate to obtain the target steering wheel angle of the target vehicle. The steering wheel angle calculation method provided in the embodiment of the present application can help reduce the error between the steering wheel angle of the vehicle's lateral movement and the steering wheel angle required to track the vehicle's self-planned desired driving trajectory, effectively reducing the deviation between the vehicle's current driving trajectory and the vehicle's self-planned desired driving trajectory, and improving the accuracy of vehicle driving.

[0066] From the above introduction, it can be seen that the steering wheel angle calculation method provided in the embodiment of the present application can compensate the first steering wheel angle based on the preset reverse stretching rate to obtain the target steering wheel angle of the target vehicle. Figure 3 and Figure 4 , introduces the calculation process of the preset reverse stretching rate, which may include the following steps:

[0067] Step S201 : Decomposing the driving speed of the target vehicle at the center of gravity projection point to obtain a nonlinear speed component and a linear speed component at the center of gravity.

[0068] Specifically, as can be seen from the above introduction, the method provided in the embodiment of the present application can use a linear analysis method to determine the steering wheel angle of the target vehicle.

[0069] In practical applications, the target vehicle's speed can be decomposed at the projection point of the vehicle's center of gravity on the road the vehicle is traveling on, and the nonlinear velocity component and linear velocity component of the vehicle at the center of gravity can be obtained, so that the forward stretch rate can be solved.

[0070] in,

[0071] The center of gravity projection point is the projection point of the center of gravity of the target vehicle on the road on which it is traveling;

[0072] The linear velocity component at the center of gravity includes a first velocity of the target vehicle along a road tangent direction and a second velocity along a road normal direction.

[0073] The nonlinear velocity component at the center of gravity includes a third velocity of the target vehicle along the tangent direction of the road and a fourth velocity along the normal direction of the road.

[0074] like Figure 3 and Figure 4 As shown in the figure, θ represents the steering wheel, that is, the front wheel angle, a and b represent the stretch ratio, L is the wheelbase of the vehicle, Indicates the angle between the vehicle's body and the road direction. Figure 3 A schematic diagram showing the effect of analyzing the instantaneous motion trajectory of a vehicle using a linearization method according to an embodiment of the present application;

[0075] Figure 4 A schematic diagram showing the effect of analyzing the instantaneous motion trajectory of a vehicle using a nonlinear method according to an embodiment of the present application;

[0076] The first rate is recorded as: ;

[0077] Then the second rate can be: ;

[0078] The third rate may be: ;

[0079] The fourth rate may be: ;

[0080] Step S202 : simulate the nonlinear velocity component at the center of gravity into a center of gravity circular trajectory, simulate the linear velocity component into a center of gravity elliptical trajectory, and calculate the forward stretching rate of the center of gravity circular trajectory into the center of gravity elliptical trajectory.

[0081] Specifically, in actual application, when a vehicle is moving laterally, all points on the vehicle move along a trajectory around the same center of a circle to adjust the direction.

[0082] The linearization analysis method is to regard the trajectory of all points on the target vehicle around the same center of a circle when the target vehicle is moving laterally as an elliptical trajectory.

[0083] In actual driving, when a vehicle is moving laterally, all points on the vehicle move around the same center of a circle, and the trajectory formed can be regarded as a circular trajectory.

[0084] In the method provided in an embodiment of the present application, the nonlinear velocity component of the target vehicle at the center of gravity can be simulated as a center of gravity circular trajectory, and the linear velocity component can be simulated as a center of gravity elliptical trajectory. After obtaining the center of gravity circular trajectory and the center of gravity elliptical trajectory, the positive stretching rate of the center of gravity circular trajectory to the center of gravity elliptical trajectory can be further solved.

[0085] In order to improve calculation efficiency, the nonlinear velocity component may be calculated using a preset linear model, and the linear velocity component may be calculated using a preset nonlinear model linear model.

[0086] Step S203: Obtain the reverse stretching rate according to the forward stretching rate.

[0087] Specifically, as described above, the method provided in the embodiments of the present application can determine the positive stretching rate of the barycentric circular trajectory transformed into the barycentric elliptical trajectory. Based on the positive stretching rate, the negative stretching rate of the barycentric elliptical trajectory transformed into the barycentric circular trajectory can be determined. This can be used to calculate the target direction wheel rotation angle.

[0088] The value of the forward stretching rate is equal to the value of the reverse stretching rate.

[0089] As can be seen from the technical solutions introduced above, the method provided in the embodiment of the present application can solve the positive stretching rate of the transformation of the circular trajectory of the center of gravity into the elliptical trajectory of the center of gravity by simulating the nonlinear velocity component at the center of gravity into a circular trajectory of the center of gravity and the linear velocity component into an elliptical trajectory of the center of gravity. The reverse stretching rate is thereby determined so that it can be used to calculate the target steering wheel angle of the vehicle. The steering wheel angle calculation method provided in the embodiment of the present application can help reduce the error between the steering wheel angle of the vehicle's lateral movement and the steering wheel angle required to track the desired driving trajectory route planned by the vehicle itself, can effectively reduce the deviation between the vehicle's current driving trajectory route and the desired driving trajectory route planned by the vehicle itself, and improve the accuracy of vehicle driving.

[0090] In actual application, the method provided in the embodiment of the present application can compensate the first direction wheel turning angle based on a preset reverse stretching rate to obtain the target direction wheel turning angle of the target vehicle. The following describes the process of compensating the first direction wheel turning angle to obtain the target direction wheel turning angle of the target vehicle. The process may include the following steps:

[0091] Step S301 : Decompose the driving speed of the target vehicle at the non-directional wheels to obtain non-directional wheel linear speed components.

[0092] Specifically, from the above introduction, it can be seen that the method provided in the embodiment of the present application can use a linear analysis method to decompose the speed of the target vehicle. Therefore, the driving speed of the target vehicle can be decomposed at the non-directional wheel, thereby obtaining the non-directional wheel linear velocity component.

[0093] The non-directional wheel linear velocity component may be a velocity component calculated using a preset linear model.

[0094] Step S302: Correcting the linear trajectory represented by the non-directional wheel linear velocity component using the reverse stretching rate, and constructing a conversion relationship between the first directional wheel angle, the reverse stretching rate, and the target directional wheel angle.

[0095] Specifically, after determining the non-directional wheel linear velocity component, the linear trajectory represented by the non-directional wheel linear velocity component can be corrected using the reverse stretching rate based on the relationship between the nonlinear velocity component and the linearized velocity component of the target vehicle at the center of gravity projection, and a conversion relationship between the first directional wheel angle, the reverse stretching rate and the target directional wheel angle is constructed, so that the target directional wheel angle can be calculated based on the first directional wheel angle and the directional stretching rate.

[0096] The conversion relationship between the first direction wheel rotation angle, the reverse stretching rate and the target direction wheel rotation angle may include the following:

[0097]

[0098] in,

[0099] It can represent the preset reverse stretching rate;

[0100] It can represent the first direction wheel angle;

[0101] The target direction wheel angle may be represented.

[0102] Step S303: Calculate the target direction wheel angle of the target vehicle according to the conversion relationship.

[0103] Specifically, from the above introduction, it can be seen that the above steps can determine the conversion relationship between the first direction wheel turning angle, the reverse stretching rate and the target direction wheel turning angle. Therefore, after determining the first direction wheel turning angle, the target direction wheel turning angle of the target vehicle can be calculated based on the conversion relationship and the preset reverse stretching rate.

[0104] From the above introduction, it can be seen that the method provided in the embodiment of the present application can perform compensation calculation on the first steering wheel angle based on a preset reverse stretching rate to obtain the target steering wheel angle of the target vehicle. The steering wheel angle calculation method provided in the embodiment of the present application can help reduce the error between the steering wheel angle of the vehicle's lateral movement and the steering wheel angle required to track the desired driving trajectory route planned by the vehicle itself, and can effectively reduce the deviation between the vehicle's current driving trajectory route and the desired driving trajectory route planned by the vehicle itself, and improve the accuracy of the vehicle's driving.

[0105] As can be seen from the above description, the method provided in the embodiment of the present application can simulate the nonlinear velocity component at the center of gravity into a circular trajectory of the center of gravity, and the linear velocity component into an elliptical trajectory of the center of gravity, and solve the positive stretching rate of the transformation of the circular trajectory of the center of gravity into the elliptical trajectory of the center of gravity. The process is described below, which may include the following steps:

[0106] Step S401: Compare the first rate and the third rate to obtain a first stretching ratio.

[0107] Specifically, from the above introduction, it can be seen that the method provided in the embodiment of the present application can decompose the driving speed of the target vehicle at the center, thereby obtaining the first rate and the third rate, and thus the first rate and the third rate can be compared to obtain a first stretching ratio, wherein the first stretching ratio can characterize the trajectory stretching ratio of the target vehicle's driving speed along the tangent direction of the road, that is, the stretching ratio of the circular trajectory and the elliptical trajectory along the tangent direction of the road.

[0108] The calculation formula of the first stretching ratio may include the following:

[0109]

[0110] in,

[0111] may represent the first stretch ratio;

[0112] may represent said first rate;

[0113] may represent said third rate;

[0114] It can represent the wheel heading angle of the target vehicle performing the driving task.

[0115] Step S402: Compare the second rate and the fourth rate to obtain a second stretching ratio.

[0116] Specifically, from the above introduction, it can be seen that the method provided in the embodiment of the present application can decompose the driving speed of the target vehicle at the center, thereby obtaining the second rate and the fourth rate, and thus the second rate and the fourth rate can be compared to obtain the second stretching ratio, wherein the first stretching ratio can characterize the trajectory stretching ratio of the target vehicle's driving speed along the road normal direction, that is, the stretching ratio of the circular trajectory and the elliptical trajectory along the road normal direction.

[0117] The calculation formula of the first stretching ratio may include the following:

[0118]

[0119] in,

[0120] may represent the first stretch ratio;

[0121] may represent the second rate;

[0122] may represent said fourth rate;

[0123] It can represent the wheel heading angle of the target vehicle performing the driving task.

[0124] Step S403: Substitute the first stretching ratio and the second stretching ratio into the ellipse curvature formula to obtain the forward stretching ratio.

[0125] Specifically, it can be seen from the technical solutions introduced above that the method provided in the embodiment of the present application can calculate the first stretching ratio and the second stretching ratio.

[0126] The first stretching ratio and the second stretching ratio are substituted into the ellipse curvature formula to obtain the forward stretching ratio.

[0127] The calculation formula of the forward stretch rate may include the following:

[0128]

[0129] in,

[0130] It may indicate determining a first curvature of the instantaneous motion trajectory of the target vehicle at the center of gravity by using a preset linear model;

[0131] It can represent a second curvature of the instantaneous motion trajectory of the target vehicle after compensating the steering wheel angle at the center of gravity;

[0132] A first stretching ratio of the speed of the target vehicle at the target point along the tangential direction may be represented;

[0133] A second stretching ratio of the target vehicle's velocity at the target point along the normal direction may be represented;

[0134] It can indicate the time the vehicle has been traveling.

[0135] As can be seen from the technical solutions described above, the method provided in the embodiments of the present application can simulate the nonlinear velocity component at the center of gravity into a circular trajectory of the center of gravity, and the linear velocity component into an elliptical trajectory of the center of gravity, and solve the positive stretching rate of the transformation of the circular trajectory of the center of gravity into the elliptical trajectory of the center of gravity, so that the negative stretching rate can be solved based on the positive stretching rate. Based on the negative stretching rate, the first steering angle can be compensated and calculated to obtain the target steering angle of the target vehicle. The steering angle calculation method provided in the embodiments of the present application can help reduce the error between the steering angle of the vehicle's lateral movement and the steering angle required to track the desired driving trajectory route planned by the vehicle itself, and can effectively reduce the deviation between the vehicle's current driving trajectory and the desired driving trajectory route planned by the vehicle itself, and improve the accuracy of vehicle driving.

[0136] As can be seen from the above description, the embodiment of the present application can determine the first direction wheel angle of the target vehicle. The following describes the process, which may include the following steps:

[0137] Step S501: Acquire the real-time speed of the target vehicle.

[0138] Specifically, in actual application, when a vehicle moves laterally, the vehicle's steering wheel angle is related to the vehicle's real-time speed. Therefore, before determining the first steering wheel angle of the target vehicle, the real-time speed of the target vehicle can be obtained first so that the first steering wheel angle can be calculated using the real-time speed of the target vehicle.

[0139] Step S502: Determine the real-time rotation radius of the non-directional wheel of the target vehicle using a preset linear model according to the real-time speed.

[0140] Specifically, as can be seen from the above introduction, the method provided in the embodiment of the present application can determine the real-time speed of the target vehicle. After determining the real-time speed, the real-time speed can be used to calculate the real-time rotation radius of the non-directional wheel of the target vehicle.

[0141] in,

[0142] The following calculation formula can be used to calculate the real-time rotation radius of the non-directional wheel:

[0143]

[0144] in,

[0145] It can represent the real-time rotation radius of the non-directional wheels of the target vehicle;

[0146] The real-time speed of the target vehicle can be represented;

[0147] It can represent the angular velocity of the target vehicle.

[0148] Step S503: Calculate the first steering wheel rotation angle by using the real-time rotation radius of the non-steering wheel and obtaining the distance between the midpoint of the steering wheel axis and the midpoint of the non-steering wheel axis of the target vehicle.

[0149] Specifically, as can be seen from the above description, the method provided in the embodiments of the present application can determine the real-time rotation radius of the non-directional wheel. The steering wheel rotation angle of the target vehicle is related to the real-time rotation radius of the non-directional wheel of the target vehicle. Therefore, after determining the real-time rotation radius of the non-directional wheel, the distance from the midpoint of the steering wheel axis to the midpoint of the non-directional wheel axis of the target vehicle can be further obtained. The first steering wheel rotation angle can then be calculated using a preset linear model, so that it can be used to calculate the target steering wheel rotation angle of the target vehicle.

[0150] The distance from the midpoint of the directional wheel axis to the midpoint of the non-directional wheel axis of the target vehicle can be recorded as the wheelbase of the target vehicle, and the symbol L can be used to represent the wheelbase of the target vehicle.

[0151] In addition, any other calculation method may be used to obtain the first direction wheel angle.

[0152] For example, the first-direction wheel turning angle may be calculated using the angle between the body of the target vehicle and the road on which the target vehicle is currently traveling.

[0153] The instantaneous turning radius of the target vehicle may also be calculated according to a preset nonlinear model, and the first direction wheel angle may be further calculated.

[0154] For example, the calculation formula of the first direction wheel angle can be as follows:

[0155]

[0156] in,

[0157] It can represent the first direction wheel angle;

[0158] It can represent the wheelbase of the target vehicle;

[0159] It can represent the real-time turning radius of the non-directional wheels of the target vehicle.

[0160] As can be seen from the technical solutions described above, the method provided in the embodiments of the present application can determine the vehicle's initial steering wheel angle based on the real-time turning radius of the vehicle's non-steering wheels, the vehicle's instantaneous turning radius, or the vehicle's real-time speed, so that a compensation calculation can be performed based on the vehicle's initial steering wheel angle to determine the vehicle's target steering wheel angle. The steering wheel angle calculation method provided in the embodiments of the present application can help reduce the error between the steering wheel angle of the vehicle's lateral movement and the steering wheel angle required to track the vehicle's self-planned desired driving trajectory, effectively reduce the deviation between the vehicle's current driving trajectory and the vehicle's self-planned desired driving trajectory, and improve the accuracy of the vehicle's driving.

[0161] In actual application, when the angle of lateral movement of the target vehicle's driving direction is not large, it is possible that the vehicle is slightly adjusting the current driving direction, which is not considered to be a lateral movement. At the control terminal of the target vehicle, the error of the first direction wheel turning angle of the target vehicle determined is not large, and there is no need to make a lateral adjustment to the current driving direction. The target vehicle can directly adjust the direction of lateral movement according to the first direction wheel turning angle and will not deviate from the desired driving trajectory. When the angle of lateral movement of the target vehicle's driving direction exceeds a certain angle, the error of the first direction wheel turning angle of the target vehicle determined at the control terminal of the target vehicle will be too large. At this time, the vehicle may need to change its current driving direction and move in a lateral direction. Next, the process of how to determine whether the driving direction of the target vehicle has moved laterally is introduced. This process may include the following steps:

[0162] Step S601: Determine a first angle between the body orientation of the target vehicle and the road direction.

[0163] Specifically, when the vehicle moves laterally, the error of the preset steering wheel angle is related to the angle between the vehicle body direction and the road direction.

[0164] Therefore, if it is necessary to determine whether a vehicle needs to move laterally, a first angle between the vehicle body and the road direction can be determined. This first angle can be analyzed to determine whether the vehicle needs to change its current direction of travel and move laterally.

[0165] Step S602: Determine whether the first angle is greater than a preset first threshold.

[0166] Specifically, as can be seen from the above description, the size of the first angle determines the size of the error of the first steering wheel angle. Therefore, after determining the first angle, it can be determined whether the first angle is greater than a preset first threshold.

[0167] Whether the vehicle needs to adjust its current driving direction and move laterally is determined by judging the relationship between the size of the first angle and the preset first threshold.

[0168] The value range of the preset first threshold can be set to [0°, 20°].

[0169] Among them, it is known from experiments that when the preset first threshold is 15°, the error of the first direction wheel angle of the target vehicle determined at the control terminal of the target vehicle will gradually be displayed, which indicates that the vehicle is about to move laterally.

[0170] Step S603: Determine whether the target vehicle's driving direction has moved laterally.

[0171] Specifically, from the above introduction, it can be seen that the method provided in the embodiment of the present application can determine the relationship between the first angle and the preset first threshold value. If the first angle is greater than the preset first threshold value, it means that at the control terminal of the target vehicle, the error of the first direction wheel turning angle of the target vehicle determined will be too large, and the determined first direction wheel turning angle needs to be compensated and calculated. It also means that the driving direction of the target vehicle has moved laterally.

[0172] As can be seen from the technical solutions described above, the method provided in the embodiment of the present application determines whether the vehicle has moved laterally by analyzing the relationship between the first angle and a preset first threshold, so as to determine whether it is necessary to calculate the vehicle's steering wheel angle.

[0173] The following describes a steering wheel angle calculation device provided in an embodiment of the present application. The steering wheel angle calculation device described below and the steering wheel angle calculation method described above can refer to each other.

[0174] See also Figure 5 , Figure 5 This is a schematic structural diagram of a steering wheel angle calculation device disclosed in an embodiment of the present application.

[0175] like Figure 5 As shown, the steering wheel angle calculation device may include:

[0176] The first calculation unit 101 is configured to determine a first direction wheel turning angle of the target vehicle at a control terminal of the target vehicle when the target vehicle's driving direction moves laterally;

[0177] The second calculation unit 102 is configured to perform compensation calculation on the first direction wheel turning angle based on a preset reverse stretching rate to obtain a target direction wheel turning angle of the target vehicle.

[0178] As can be seen from the technical solution introduced above, when the target vehicle's driving direction moves laterally, the steering wheel angle calculation device provided in the embodiment of the present application can use the first calculation unit 101 to determine the first steering wheel angle of the target vehicle at the control terminal of the target vehicle; after determining the first steering wheel angle, the second calculation unit 102 can be used to compensate the first steering wheel angle based on a preset reverse stretching rate to obtain the target steering wheel angle of the target vehicle. The steering wheel angle calculation device provided in the embodiment of the present application can help reduce the error between the steering wheel angle of the vehicle's lateral movement and the steering wheel angle required to track the desired driving trajectory route planned by the vehicle itself, can effectively reduce the deviation between the vehicle's current driving trajectory route and the desired driving trajectory route planned by the vehicle itself, and improve the accuracy of vehicle driving.

[0179] Further optionally, the step of calculating the reverse stretching rate may include:

[0180] Decomposing the target vehicle's speed at the center of gravity projection point to obtain a nonlinear speed component and a linear speed component at the center of gravity;

[0181] The nonlinear velocity component at the center of gravity is simulated into a center of gravity circular trajectory, and the linear velocity component is simulated into a center of gravity elliptical trajectory, and the positive stretching rate of the center of gravity circular trajectory to the center of gravity elliptical trajectory is solved;

[0182] According to the forward stretching rate, the reverse stretching rate is obtained;

[0183] Wherein, the center of gravity projection point is the projection point of the center of gravity of the target vehicle on the road on which it is traveling;

[0184] The linear velocity component at the center of gravity includes a first velocity of the target vehicle along a tangent direction of the road and a second velocity along a normal direction of the road;

[0185] The nonlinear velocity component at the center of gravity includes a third velocity of the target vehicle along the tangent direction of the road and a fourth velocity along the normal direction of the road.

[0186] Further optionally, the second calculating unit 102 may include:

[0187] a speed component acquisition unit, configured to decompose the travel speed of the target vehicle at the non-directional wheel to obtain a non-directional wheel linear speed component;

[0188] a conversion relationship acquisition unit, configured to correct the linear trajectory represented by the non-directional wheel linear velocity component using the reverse stretching rate, and construct a conversion relationship between the first directional wheel angle, the reverse stretching rate, and the target directional wheel angle;

[0189] The target direction wheel turning angle calculation unit is used to calculate the target direction wheel turning angle of the target vehicle according to the conversion relationship.

[0190] Further optionally, the process of simulating the nonlinear velocity component at the center of gravity into a circular trajectory of the center of gravity, simulating the linear velocity component into an elliptical trajectory of the center of gravity, and solving the forward stretching rate of the transformation of the circular trajectory of the center of gravity into the elliptical trajectory of the center of gravity may include:

[0191] Comparing the first rate and the third rate to obtain a first stretching ratio;

[0192] Comparing the second rate and the fourth rate to obtain a second stretching ratio;

[0193] The first stretching ratio and the second stretching ratio are substituted into the ellipse curvature formula to obtain the forward stretching ratio.

[0194] Further optionally, the process of determining the first direction wheel turning angle of the target vehicle may include:

[0195] Obtaining the real-time speed of the target vehicle;

[0196] Determine the real-time rotation radius of the non-directional wheel of the target vehicle using a preset linear model according to the real-time speed;

[0197] The first steering wheel rotation angle is calculated by using the real-time rotation radius of the non-steering wheel and obtaining the distance between the midpoint of the steering wheel axis and the midpoint of the non-steering wheel axis of the target vehicle.

[0198] Further optionally, the device may also include:

[0199] a judgment unit, configured to judge whether the target vehicle moves laterally in its driving direction;

[0200] The judging unit may include:

[0201] a first angle determining unit, configured to determine a first angle between the body orientation of the target vehicle and the road direction;

[0202] a judging subunit, configured to judge whether the first angle is greater than a preset first threshold;

[0203] The direction movement determining unit is configured to determine that the target vehicle's traveling direction has moved laterally when the judgment subunit determines that the first angle is greater than the first threshold value.

[0204] Further optionally, the preset first threshold may be in the range of [0°, 20°].

[0205] The specific processing flow of each unit included in the steering wheel angle calculation device can refer to the relevant introduction of the steering wheel angle calculation method above, which will not be repeated here.

[0206] The steering wheel angle calculation device provided in the embodiment of the present application can be applied to a steering wheel angle calculation device, such as a terminal: a vehicle-mounted computing terminal, a mobile phone, a computer, etc. Optionally, Figure 6 The hardware structure diagram of the steering wheel angle calculation device is shown. Figure 6 The hardware structure of the steering wheel angle calculation device may include: at least one processor 1, at least one communication interface 2, at least one memory 3 and at least one communication bus 4.

[0207] In an embodiment of the present application, the number of processor 1 , communication interface 2 , memory 3 , and communication bus 4 is at least one, and the processor 1 , communication interface 2 , and memory 3 communicate with each other through the communication bus 4 .

[0208] The processor 1 may be a central processing unit (CPU), or an application-specific integrated circuit (ASIC), or one or more integrated circuits configured to implement the embodiments of the present application;

[0209] The memory 3 may include a high-speed RAM memory, and may also include a non-volatile memory (non-volatile memory), such as at least one disk memory;

[0210] The memory stores a program, and the processor can call the program stored in the memory, wherein the program is used to implement each processing flow in the aforementioned terminal steering wheel angle calculation solution.

[0211] An embodiment of the present application further provides a readable storage medium, which may store a program suitable for execution by a processor, wherein the program is used to implement various processing flows of the aforementioned terminal in the steering wheel angle calculation solution.

[0212] Finally, it should be noted that, in this document, relational terms such as first and second, etc., are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the terms "comprises," "comprising," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or device comprising a series of elements includes not only those elements, but also other elements not explicitly listed, or elements inherent to such process, method, article, or device. In the absence of further limitations, an element defined by the phrase "comprising a ..." does not exclude the presence of additional identical elements in the process, method, article, or device comprising the element.

[0213] The various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the various embodiments can be referenced to each other.

[0214] The above description of the disclosed embodiments is intended to enable those skilled in the art to implement or use the present application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present application. The various embodiments may be combined with one another. Therefore, the present application is not limited to the embodiments shown herein, but is intended to conform to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A method for calculating a steering wheel angle, characterized in that: include: When the target vehicle's driving direction moves laterally, determining a first direction wheel turning angle of the target vehicle at a control terminal of the target vehicle; Based on a preset reverse stretching rate, performing compensation calculation on the first direction wheel turning angle to obtain a target direction wheel turning angle of the target vehicle; The calculation expression of the preset reverse stretching rate is: , Indicates that a first curvature of the instantaneous motion trajectory of the target vehicle at the center of gravity is determined using a preset linear model; The second curvature represents the instantaneous motion trajectory after compensating the steering wheel angle of the target vehicle at the center of gravity.

2. The method according to claim 1, characterized in that The step of calculating the reverse stretching rate comprises: Decomposing the driving speed of the target vehicle at a center of gravity projection point to obtain a nonlinear speed component and a linear speed component at the center of gravity, respectively; the center of gravity projection point is a projection point of the center of gravity of the target vehicle on the road on which it is traveling; The nonlinear velocity component at the center of gravity is simulated into a center of gravity circular trajectory, and the linear velocity component is simulated into a center of gravity elliptical trajectory, and the positive stretching rate of the center of gravity circular trajectory to the center of gravity elliptical trajectory is solved; The reverse stretching ratio is obtained according to the forward stretching ratio.

3. The method according to claim 2, characterized in that The step of performing compensation calculation on the first direction wheel turning angle to obtain the target direction wheel turning angle of the target vehicle includes: Decomposing the target vehicle's travel speed at the non-directional wheel to obtain a non-directional wheel linear velocity component; Correcting the linear trajectory represented by the non-directional wheel linear velocity component using the reverse stretching rate, and constructing a conversion relationship between the first directional wheel angle, the reverse stretching rate, and the target directional wheel angle; The target direction wheel turning angle of the target vehicle is calculated based on the conversion relationship.

4. The method according to claim 2, characterized in that The linear velocity component at the center of gravity includes a first velocity of the target vehicle along a tangent direction of the road and a second velocity along a normal direction of the road; The nonlinear velocity component at the center of gravity includes a third velocity of the target vehicle along the tangent direction of the road and a fourth velocity along the normal direction of the road.

5. The method according to claim 4, characterized in that The method of simulating the nonlinear velocity component at the center of gravity into a center of gravity circular trajectory and the linear velocity component into a center of gravity elliptical trajectory, and solving the forward stretching rate of the center of gravity circular trajectory into the center of gravity elliptical trajectory, includes: Comparing the first rate and the third rate to obtain a first stretching ratio; Comparing the second rate and the fourth rate to obtain a second stretching ratio; The first stretching ratio and the second stretching ratio are substituted into the ellipse curvature formula to obtain the forward stretching ratio.

6. The method according to any one of claims 1 to 5, characterized in that The step of determining a first direction wheel turning angle of the target vehicle comprises: Obtaining the real-time speed of the target vehicle; Determine the real-time rotation radius of the non-directional wheel of the target vehicle using a preset linear model according to the real-time speed; The first steering wheel rotation angle is calculated by using the real-time rotation radius of the non-steering wheel and obtaining the distance between the midpoint of the steering wheel axis and the midpoint of the non-steering wheel axis of the target vehicle.

7. The method according to any one of claims 1 to 5, characterized in that Determining whether the target vehicle's travel direction has moved laterally includes: Determining a first angle between the body orientation of the target vehicle and the road direction; Determining whether the first angle is greater than a preset first threshold; If the first angle is greater than the first threshold, it is determined that the driving direction of the target vehicle has moved laterally.

8. The method according to any one of claim 7, characterized in that The value range of the preset first threshold is [0°, 20°].

9. A device for calculating a steering wheel angle, characterized in that: include: a first calculation unit, configured to determine a first direction wheel turning angle of the target vehicle at a control terminal of the target vehicle when the target vehicle's driving direction moves laterally; a second calculation unit, configured to perform compensation calculation on the first direction wheel turning angle based on a preset reverse stretching rate to obtain a target direction wheel turning angle of the target vehicle; The calculation expression of the preset reverse stretching rate is: , Indicates that a first curvature of the instantaneous motion trajectory of the target vehicle at the center of gravity is determined using a preset linear model; The second curvature represents the instantaneous motion trajectory after compensating the steering wheel angle of the target vehicle at the center of gravity.

10. A steering wheel angle calculation device, characterized in that: include: one or more processors, and memory; The memory stores computer-readable instructions, wherein when the computer-readable instructions are executed by the one or more processors, the steps of the method for calculating the steering wheel angle according to any one of claims 1 to 8 are implemented.

11. A readable storage medium, characterized in that: The readable storage medium stores computer-readable instructions, and when the computer-readable instructions are executed by one or more processors, the one or more processors implement the steps of the method for calculating the steering wheel angle as described in any one of claims 1 to 8.

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