Vehicle turning radius detection method, vehicle control method, device and storage medium

Abstract

The present application discloses a method for detecting the turning radius of a vehicle, a vehicle control method, a device and a storage medium, including: obtaining the head steering angle, wheel attitude parameters and factory design parameters of the vehicle. Calculating the steering radius of the handlebar of the vehicle by calculating the head steering angle of the vehicle and the factory design parameters, and calculating the roll steering radius of the vehicle body by calculating the wheel attitude parameters of the vehicle and the factory design parameters. It is possible to simultaneously consider the front wheel steering angle and the wheel roll angle when the vehicle is turning in a steady state, and perform a fusion calculation on the steering radius of the handlebar and the roll steering radius of the vehicle body, which can improve the real-time performance and accuracy of the effective turning radius detection of the motorcycle.

Description

Technical Field

[0001] This application relates to the technical field of motorcycle system control, and particularly to a method for detecting the turning radius of a vehicle, a method for controlling a vehicle, a device, and a storage medium. Background Art

[0002] A motorcycle is a two-wheeled unbalanced means of transportation, and the effective turning radius of a motorcycle has an important impact on the turning control of the motorcycle. Currently, although an automobile can calculate the effective turning radius through the proportional relationship between the Ackermann angle and the steering wheel angle, the turning principle of a motorcycle is different from that of an automobile. The effective turning radius of a motorcycle is not only determined by the steering angle of the front of the vehicle but also affected by more complex dynamic factors, such as the roll angle of the wheels.

[0003] However, current motorcycle turning skills basically rely on the ability and experience of the driver, and there is no unified formula or theory in the industry to accurately calculate the effective turning radius of a motorcycle. Summary of the Invention

[0004] This application provides a method for detecting the turning radius of a vehicle, a method for controlling a vehicle, a device, and a storage medium, which can improve the real-time performance and accuracy of detecting the effective turning radius of a motorcycle.

[0005] One technical solution adopted by this application is: providing a method for detecting the turning radius of a vehicle, the method for detecting the turning radius of a vehicle includes: obtaining the steering angle of the front of the vehicle, the wheel attitude parameters, and the factory design parameters. Calculating the steering radius of the handlebar of the vehicle by calculating the steering angle of the front of the vehicle and the factory design parameters. Calculating the roll steering radius of the vehicle body by calculating the wheel attitude parameters and the factory design parameters. Calculating the effective turning radius of the vehicle by fusing and calculating the steering radius of the handlebar and the roll steering radius of the vehicle body.

[0006] In some embodiments, calculating the effective turning radius of the vehicle by fusing and calculating the steering radius of the handlebar and the roll steering radius of the vehicle body includes: using the contact point between the rear tire of the vehicle and the ground as the coordinate origin to construct a vehicle kinematic coordinate system. Performing a spatial transformation and projection operation on the steering radius of the handlebar and the roll steering radius of the vehicle body to obtain the turning parameters in the vehicle kinematic coordinate system; wherein, the turning parameters include the center coordinates of the steering radius of the handlebar, the converted steering radius of the handlebar, the center coordinates of the roll steering radius, and the converted roll steering radius of the vehicle body. Determining a turning geometric triangle according to the turning parameters and the coordinate origin. Solving the perpendicular direction radius of the turning geometric triangle and the forward tangent of the vehicle tire to obtain the effective turning radius.

[0007] In some embodiments, a spatial transformation and projection operation is performed on the steering radius of the handlebar and the roll steering radius of the vehicle body to obtain the turning parameters in the vehicle kinematic coordinate system, including: successively performing a rotation coordinate system transformation in three-dimensional space, a three-dimensional transformation matrix operation, and an orthogonal projection onto the vehicle kinematic coordinate system on the steering radius of the handlebar and the roll steering radius of the vehicle body to obtain the turning parameters.

[0008] In some embodiments, a turning geometric triangle is determined based on the turning parameters and the coordinate origin, including: determining the origin position of the roll steering radius of the vehicle body below the ground plane and the origin position of the steering radius of the handlebar in the vehicle kinematic coordinate system according to the positions of the turning parameters and the coordinate origin. A turning geometric triangle is determined according to the position of the coordinate origin, the origin position of the roll steering radius of the vehicle body below the ground plane, and the origin position of the steering radius of the handlebar.

[0009] In some embodiments, the factory design parameters include the front and rear wheel wheelbase, the front steering mechanism parameters, and the front wheel tire size parameters; the steering angle of the vehicle head is calculated with the factory design parameters to obtain the steering radius of the handlebar of the vehicle, including: performing geometric operations on the steering angle of the vehicle head, the front and rear wheel wheelbase, the front steering mechanism parameters, and the front wheel tire size parameters to obtain the steering radius of the handlebar.

[0010] In some embodiments, the wheel attitude parameters include the wheel roll angle, and the factory design parameters include the rear wheel tire size parameters; the wheel attitude parameters are calculated with the factory design parameters to obtain the roll steering radius of the vehicle body, including: performing geometric operations on the wheel roll angle and the rear wheel tire size parameters to obtain the actual ground contact rolling radius. Geometric operations are performed on the actual ground contact rolling radius and the wheel roll angle to obtain the roll steering radius of the vehicle body.

[0011] In some embodiments, the steering radius of the handlebar and the roll steering radius of the vehicle body are fused and calculated to obtain the effective turning radius of the vehicle, including: obtaining the tire slip rate of the vehicle. In response to the wheel attitude parameters satisfying the preset stability condition and the tire slip rate satisfying the preset limit condition, perform the step of fusing and calculating the steering radius of the handlebar and the roll steering radius of the vehicle body to obtain the effective turning radius of the vehicle. In response to the wheel attitude parameters not satisfying the stability condition and / or the tire slip rate not satisfying the limit condition, maintain the effective turning radius of the previous cycle.

[0012] In some embodiments, the wheel attitude parameters include the wheel pitch angle and the wheel yaw angle, and the tire slip ratio includes the front wheel slip ratio and the rear wheel slip ratio; in response to the wheel attitude parameters satisfying the preset stability condition and the tire slip ratio satisfying the preset limit condition, it includes: detecting that the wheel pitch angle is less than the preset vehicle body steady-state pitch angle limit value, and determining that the wheel pitch angle satisfies the stability condition. Detecting that the wheel yaw angle is less than the preset vehicle body steady-state yaw angle limit value, and determining that the wheel yaw angle satisfies the stability condition. Detecting that the front wheel slip ratio is less than the preset first vehicle body steady-state slip ratio, and determining that the front wheel slip ratio satisfies the limit condition. Detecting that the rear wheel slip ratio is less than the preset second vehicle body steady-state slip ratio, and determining that the rear wheel slip ratio satisfies the limit condition.

[0013] Another technical solution adopted in this application is: to provide a vehicle control method, the vehicle control method includes: obtaining the effective turning radius of the vehicle; wherein, the effective turning radius is obtained based on the vehicle turning radius detection method of any one of the above; performing vehicle control based on the effective turning radius.

[0014] Another technical solution adopted in this application is: to provide an electronic device, the electronic device includes: a memory for storing executable program code. A processor for calling and running the executable program code from the memory, so that the electronic device executes the vehicle turning radius detection method or the vehicle control method of any one of the above.

[0015] Another technical solution adopted in this application is: to provide a computer-readable storage medium, the computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, it implements the vehicle turning radius detection method or the vehicle control method of any one of the above.

[0016] An embodiment of this application provides a vehicle turning radius detection method, the vehicle turning radius detection method includes: obtaining the head steering angle, wheel attitude parameters and factory design parameters of the vehicle; calculating the head steering angle and the factory design parameters to obtain the handlebar turning radius of the vehicle; calculating the wheel attitude parameters and the factory design parameters to obtain the body roll turning radius of the vehicle; performing a fusion calculation on the handlebar turning radius and the body roll turning radius to obtain the effective turning radius of the vehicle. By calculating the head steering angle of the vehicle and the factory design parameters to obtain the handlebar turning radius of the vehicle, and calculating the wheel attitude parameters of the vehicle and the factory design parameters to obtain the body roll turning radius of the vehicle, the front wheel steering angle and the wheel roll angle during steady-state turning of the vehicle can be considered simultaneously, and a fusion calculation is performed on the handlebar turning radius and the body roll turning radius, which can improve the real-time performance and accuracy of the effective turning radius detection of the motorcycle. Description of the Drawings

[0017] Figure 1It is a schematic flowchart of the first embodiment of the vehicle turning radius detection method of the present application;

[0018] Figure 2 It is a schematic flowchart of the second embodiment of the vehicle turning radius detection method of the present application;

[0019] Figure 3 It is a schematic diagram of the logic of the effective turning radius calculation and estimation software unit of the vehicle turning radius detection method in an embodiment of the present application;

[0020] Figure 4a It is a front view of the motorcycle overall coordinate system definition of the vehicle turning radius detection method of the present application;

[0021] Figure 4b It is a side view of the motorcycle overall coordinate system definition of the vehicle turning radius detection method of the present application;

[0022] Figure 4c It is a top view of the motorcycle overall coordinate system definition of the vehicle turning radius detection method of the present application;

[0023] Figure 5 It is a schematic diagram of the parameters of the front steering mechanism of the motorcycle in the vehicle turning radius detection method of the present application;

[0024] Figure 6 It is a schematic diagram of the cross-section of the motorcycle hub tire in the vehicle turning radius detection method of the present application;

[0025] Figure 7 It is a geometric schematic diagram of the steering radius calculation logic of the handlebar in the vehicle turning radius detection method of the present application;

[0026] Figure 8 It is a geometric schematic diagram of the steering radius calculation logic of the body roll in the vehicle turning radius detection method of the present application;

[0027] Figure 9 It is a schematic diagram of the fusion calculation of the effective turning radius of the vehicle turning radius detection method of the present application;

[0028] Figure 10 It is a schematic diagram of the vehicle kinematic coordinate system and the turning geometric triangle in the vehicle turning radius detection method of the present application;

[0029] Figure 11 It is an exemplary flowchart of the vehicle turning radius detection method in an embodiment of the present application;

[0030] Figure 12 It is a schematic flowchart of the third embodiment of the vehicle turning radius detection method of the present application;

[0031] Figure 13It is a logical schematic diagram of the effective turning radius calculation and estimation software unit for the vehicle turning radius detection method in another embodiment of the present application;

[0032] Figure 14 It is an exemplary flowchart of the vehicle turning radius detection method in another embodiment of the present application;

[0033] Figure 15 It is an exemplary structural block diagram of the electronic device of the present application;

[0034] Figure 16 It is an exemplary structural block diagram of the computer-readable storage medium of the present application. Detailed implementation manners

[0035] The present application will be described in detail below with reference to the accompanying drawings and embodiments.

[0036] In some embodiments, please refer to Figure 1 , Figure 1 It is a flowchart of the first embodiment of the vehicle turning radius detection method of the present application. It should be noted that if there are substantially the same results, the method of the present application is not limited to Figure 1 the process sequence shown. As Figure 1 shown, the vehicle turning radius detection method includes:

[0037] Step S101, obtain the front head steering angle, wheel attitude parameters and factory design parameters of the vehicle.

[0038] Among them, the vehicle can be an electric motorcycle.

[0039] The front head steering angle refers to the steering angle of the front wheels of the vehicle, that is, the deflection angle of the front of the vehicle relative to the longitudinal axis of the vehicle. The front head steering angle can affect the movement path of the front wheels when the vehicle turns.

[0040] The factory design parameters can be fixed parameters set by the manufacturer when designing and producing the vehicle. For example, the factory design parameters can include at least one of the wheelbase of the front and rear wheels of the vehicle, the parameters of the front steering mechanism, the parameters of the front wheel tire size, and the parameters of the rear wheel tire size.

[0041] The wheel attitude parameters can be angular parameters describing the wheel attitude in three-dimensional space. It can be used to calculate the change of the wheel attitude when the vehicle turns, especially the influence of the body roll on the turning radius.

[0042] For example, the wheel attitude parameters can include at least one of the wheel pitch angle (Pitch), the wheel yaw angle (Yaw), and the wheel roll angle (Roll).

[0043] Step S102, calculate the front head steering angle and the factory design parameters to obtain the steering radius of the vehicle handlebar.

[0044] Among them, the turning radius of the handlebar faucet can be the shortest distance from the front wheel tire to the turning center during the turning process when the driver turns the vehicle handlebar. By calculating the turning angle of the vehicle head and the factory design parameters, the obtained turning radius of the handlebar faucet can be used to estimate the turning situation of the vehicle at any vehicle head turning angle.

[0045] It should be noted that in this embodiment, step S102 is taken as an example to be executed before step S103. In other embodiments, step S102 can also be executed after step S103, and step S102 can also be executed simultaneously with step S103.

[0046] Step S103: Calculate the wheel attitude parameters and the factory design parameters to obtain the body roll turning radius of the vehicle.

[0047] Among them, the body roll turning radius can be the change in the turning radius formed due to the body tilt during the turning process of the vehicle. Since the body roll turning radius will change the actual turning radius, therefore, to improve the calculation accuracy of the effective turning radius of the vehicle, the obtained body roll turning radius by calculating the wheel attitude parameters and the factory design parameters can be used to estimate the influence of the body roll on the turning radius of the vehicle.

[0048] Step S104: Perform a fusion calculation on the turning radius of the handlebar faucet and the body roll turning radius to obtain the effective turning radius of the vehicle.

[0049] Among them, the effective turning radius can be the radius of the circular trajectory during the steady-state turning (stable turning) of the vehicle on the road surface, that is, the radius of the circular trajectory left when the motorcycle turns a complete circle stably.

[0050] As an exemplary example, since when the vehicle is turning, not only the turning angle of the front wheel affects the turning radius, but also the body roll affects the actual turning radius. Therefore, by performing a fusion calculation on the turning radius of the handlebar faucet and the body roll turning radius, an accurate effective turning radius value can be obtained. The effective turning radius of the motorcycle during riding can be calculated and predicted in real time, and the effective turning radius is sent to the Controller Area Network (CAN) network of the vehicle and provided for controllers such as the vehicle instrument, the Telematics Box (T-Box), and the Anti-lock Braking System (ABS) to use, so that the motorcycle design can be based on the effective turning radius in this embodiment to implement higher-order road safety functions, assisted driving, self-balancing algorithms, intelligent driving planning and other functions.

[0051] In this embodiment, by calculating the steering angle of the vehicle's front end with the factory design parameters, the steering radius of the vehicle's handlebar is obtained, and by calculating the wheel attitude parameters of the vehicle with the factory design parameters, the roll steering radius of the vehicle's body is obtained. It is possible to take into account both the front wheel steering angle and the wheel roll angle when the vehicle is turning steadily, and by fusing the calculation of the handlebar steering radius and the body roll steering radius, the real-time performance and accuracy of the effective turning radius detection of the motorcycle can be improved.

[0052] The inventors considered that there has never been a fixed formula and theory in the industry for the scientific explanation of the turning principle of motorcycles. Different from cars, motorcycles are a means of transportation in a two-wheel unbalanced state, and their turning techniques vary greatly depending on the rider's ability and experience. Although the effective turning radius of a car can be obtained through a certain proportional function based on the relationship between the Ackermann angle of the front suspension and the steering wheel angle in the design, the effective turning radius of a motorcycle is determined not only by the front wheel steering angle but also by factors such as the wheel roll angle. However, the method for calculating and monitoring the effective turning radius of a motorcycle has always been in an ambiguous state in the industry, and it is difficult to accurately detect the effective turning radius of a motorcycle at the current moment through the various motion state parameters and vehicle design dimension parameters of the motorcycle at a certain moment.

[0053] Therefore, this application proposes a method for calculating and monitoring the effective turning radius of a motorcycle, which is applied to the Main Vehicle Control Unit (MVCU) of the motorcycle. By using the on-board Inertial Measurement Unit (IMU) hardware and software algorithm module in the MVCU, the effective turning radius of the motorcycle during riding can be calculated and predicted in real time, and the effective turning radius is sent to the vehicle CAN network for use by other controllers such as the vehicle instrument, T-Box, and ABS.

[0054] Please refer to Figure 2 , Figure 2 which is a schematic flow diagram of the second embodiment of the vehicle turning radius detection method of this application. The method includes the following steps:

[0055] Step S201, obtain the steering angle of the vehicle's front end, the wheel attitude parameters, and the factory design parameters.

[0056] As an exemplary example, please refer to Figure 3 ,the vehicle may include a steering angle sensor hardware of the front end, an on-board six-axis IMU hardware of the vehicle controller, and a vehicle controller hardware. Among them, the vehicle controller hardware is installed on the motorcycle frame, and the on-board six-axis IMU hardware of the vehicle controller is installed on the vehicle controller hardware.

[0057] This embodiment is applied to the vehicle's vehicle control unit (VCU) hardware, which may include: an Euler angle calculation software unit, and an effective turning radius calculation and prediction software unit. Through the six-axis IMU hardware on the VCU board, the X-axis acceleration, Y-axis acceleration, Z-axis acceleration, X-axis angular velocity, Y-axis angular velocity, and Z-axis angular velocity of the motorcycle are obtained, and these data are input into the Euler angle calculation software unit to obtain the wheel attitude parameters; when the vehicle is turning, the front wheel steering angular velocity can be obtained through the front wheel steering angle sensor hardware; the factory design parameters of the vehicle can be input through the host computer.

[0058] Among them, the VCU hardware can define the coordinate system of the entire vehicle. The coordinate system calculations performed by the Euler angle calculation software unit and the effective turning radius calculation and prediction software unit in the VCU hardware can follow the following vehicle coordinate system definition.

[0059] The VCU hardware can define the coordinates of the motorcycle and construct a vehicle coordinate system. Please refer to Figure 4a the front view of the vehicle shown in Figure 4b The vehicle coordinate system takes the point where the front wheel of the motorcycle touches the ground as the coordinate origin, and the front of the vehicle is the X+ direction when viewed from the side of the vehicle; please refer to Figure 4c the side view of the vehicle shown in

[0060] In some embodiments, the factory design parameters may include the wheelbase of the front and rear wheels, the parameters of the front steering mechanism, and the parameters of the front wheel tire size.

[0061] In some embodiments, please refer to Figure 5 , the parameters of the front steering mechanism may include the trail, in mm; the caster angle, in °; the rolling radius of the front wheel tire, in mm; the fork offset distance, in mm.

[0062] In some embodiments, please refer to Figure 6 , the parameters of the front wheel tire size may include the crown radius when not deflected, in mm; the maximum tire lean angle.

[0063] Step S202: Perform geometric operations on the front wheel steering angle, the wheelbase of the front and rear wheels, the parameters of the front steering mechanism, and the parameters of the front wheel tire size to obtain the steering radius of the handlebar.

[0064] As an exemplary example, please refer to Figure 7 ,Figure 7 Show the handlebar steering angle in degrees; and the front fork offset distance in mm; the installation position of the handlebar steering angle sensor hardware can be installed on the vehicle body. As an exemplary embodiment, the handlebar steering angle sensor hardware can be installed at the connection point between the front wheel tire and the front frame / battery compartment.

[0065] Perform geometric deduction calculations on the head steering angle, front steering mechanism parameters (front and rear wheel wheelbase, trail, caster angle, tire rolling radius of the front wheel, front fork offset distance), and front wheel tire size parameters (crown radius, maximum tire lean angle), and the following formula (1) can be obtained. Through the following formula (1), calculate the steering radius of the handlebar:

[0066] (1);

[0067] Where, A represents the steering radius of the handlebar; B represents the head steering angle; C represents the front and rear wheel wheelbase; D represents the front fork offset distance; E represents the caster angle.

[0068] Step S203, perform geometric operations on the wheel roll angle and the rear wheel tire size parameters to obtain the actual ground contact rolling radius.

[0069] Please refer to Figure 8 , the rear wheel tire size parameters can include the tire rolling radius of the rear wheel in mm; the tire crown radius of the rear wheel in mm; the tire ground contact width of the rear wheel in mm.

[0070] As an exemplary example, since the tire is fixedly installed on the wheel hub, and the wheel hub is connected to the vehicle body through a suspension. Assuming that the suspension is in the compressed state when the vehicle is placed naturally, the steering radius obtained by the driver by tilting the vehicle body is generated by the geometric characteristics of the tire cross-section.

[0071] Therefore, please continue to refer to Figure 8 , perform geometric deduction calculations on the wheel roll angle and the rear wheel tire size parameters (the tire crown radius of the rear wheel, the tire ground contact width of the rear wheel), and the following formula (2) can be obtained. Through the following formula (2), calculate the actual ground contact rolling radius:

[0072] f = (2);

[0073] Where, b represents the tire rolling radius in the vertical state; c represents the rear tire crown radius; d represents the wheel roll angle; e represents the tire ground contact width; f represents the actual ground contact rolling radius.

[0074] Step S204, perform geometric operations on the actual ground contact rolling radius and the wheel roll angle to obtain the body roll steering radius.

[0075] As an exemplary example, by performing a geometric calculation on the actual ground contact rolling radius and the sine angle of the wheel roll angle, the following formula (3) can be obtained, and through the following formula (3), the body roll steer radius can be calculated:

[0076] (3);

[0077] Where a represents the body roll steer radius.

[0078] Step S205: Take the contact point of the rear wheel tire of the vehicle with the ground as the coordinate origin to construct a vehicle kinematic coordinate system.

[0079] As an exemplary example, please refer to Figure 10 , take the contact point of the rear wheel tire of the motorcycle with the ground as the coordinate origin of the vehicle kinematic coordinate system, and construct the x, y, and z coordinate axes of the vehicle kinematic coordinate system.

[0080] Step S206: Perform a spatial transformation and projection operation on the handlebar turning radius and the body roll steer radius to obtain the turning parameters in the vehicle kinematic coordinate system.

[0081] Where the turning parameters may include the center coordinate of the handlebar turning radius, the converted handlebar turning radius, the center coordinate of the roll steer radius, and the converted body roll steer radius.

[0082] In some embodiments, the turning parameters include the center coordinate of the handlebar turning radius, the converted handlebar turning radius, the center coordinate of the roll steer radius, and the converted body roll steer radius.

[0083] As an exemplary example, since during the actual turning of the vehicle, the turning of the handlebar and the roll of the body will interact with each other. Therefore, through spatial transformation and projection operations, the handlebar turning radius and the body roll steer radius can be converted into the vehicle kinematic coordinate system, improving the accuracy of the analysis and optimization of the vehicle's turning performance.

[0084] Where the center coordinate of the handlebar turning radius can be the center coordinate of the handlebar turning radius in the vehicle kinematic coordinate system, representing the steering geometric center controlled by the handlebar. The converted handlebar turning radius can be the value of the handlebar turning radius in the vehicle kinematic coordinate system.

[0085] The center coordinate of the roll steer radius can be the center coordinate of the body roll steer radius in the vehicle kinematic coordinate system, indicating that as the wheel roll angle of the body changes, the steering center of gravity of the vehicle will change. The converted body roll steer radius can be the value of the body roll steer radius in the vehicle kinematic coordinate system.

[0086] In some embodiments, step S206 may include: successively performing rotation coordinate system transformation, three-dimensional transformation matrix operation, and orthogonal projection onto the vehicle kinematic coordinate system on the steering radius of the handlebar and the roll steering radius of the vehicle body in three-dimensional space to obtain turning parameters.

[0087] As an exemplary example, please refer to Figure 9 , since in most steering situations during actual motorcycle riding, it is completed under the simultaneous action of handlebar steering and roll steering. Therefore, the steering radius of the handlebar and the roll steering radius of the vehicle body are subjected to rotation coordinate system transformation, three-dimensional transformation matrix operation, and orthogonal projection onto the vehicle kinematic coordinate system for calculation to obtain turning parameters, where the turning parameters may include the center coordinates of the handlebar steering radius, the transformed steering radius of the handlebar, the center coordinates of the roll steering radius, and the transformed roll steering radius of the vehicle body.

[0088] For example, the rotation coordinate system transformation in three-dimensional space may be the Rodrigues rotation coordinate system transformation.

[0089] Step S207, determine the turning geometric triangle according to the turning parameters and the coordinate origin.

[0090] As an exemplary example, the turning geometric triangle can be used in motorcycle kinematics to analyze the relationship between handlebar steering and wheel roll angle, and further determine the geometric relationship of the effective turning radius when the motorcycle is turning. By determining the turning geometric triangle, the effective turning radius of the motorcycle when turning can be estimated more accurately, improving driving stability and safety.

[0091] In some embodiments, please continue to refer to Figure 10 , step S206 may include: determining the origin position of the roll steering radius of the vehicle body below the ground plane and the origin position of the steering radius of the handlebar in the vehicle kinematic coordinate system according to the turning parameters and the position of the coordinate origin; determining the turning geometric triangle according to the position of the coordinate origin, the origin position of the roll steering radius of the vehicle body below the ground plane, and the origin position of the steering radius of the handlebar.

[0092] As an exemplary example, since the vehicle body will roll during turning, the actual effective turning radius is not simply equal to the rear or front wheel trajectory. Therefore, the origin position of the roll steering radius of the vehicle body below the ground plane can be used to detect the influence of roll on the overall motion trajectory. At the same time, since the handlebar controls the front wheel of the vehicle and the steering radius of the front wheel is different from the trajectory of the rear wheel, the origin position of the steering radius of the handlebar can be used to detect the trajectory of the front wheel of the vehicle. Furthermore, when the vehicle is turning, using the three origin positions to determine the steering geometric triangle can be used to analyze the effective turning radius of the vehicle.

[0093] Step S208: Solve the radius in the perpendicular direction between the turning geometric triangle and the forward tangent of the vehicle's tire to obtain the effective turning radius.

[0094] Among them, when the motorcycle is moving forward, the contact points of the tire with the ground at each moment will form a trajectory that is consistent with the driving direction of the motorcycle, and the direction of this trajectory is the forward tangent. The perpendicular direction of the forward tangent can be the direction perpendicular to the forward tangent direction of the tire.

[0095] In some embodiments, step S208 may include: Solve the radius in the perpendicular direction between the turning geometric triangle and the forward tangent of the vehicle's tire to obtain the effective turning radius and the center of the effective turning radius.

[0096] As an exemplary example, by solving the radius in the perpendicular direction between the turning geometric triangle and the forward tangent of the vehicle's tire, not only can the effective turning radius be obtained, but also the center of the effective turning radius can be obtained. The center of the effective turning radius is Figure 10 shown in (X c , Y c , Z c ), which can be used to calculate the linear velocity and angular velocity of the vehicle during a roll turning.

[0097] Please continue to refer to Figure 9 and Figure 10 , in this embodiment, it is considered that since the forward direction of the wheel can also affect the turning radius of the vehicle when the vehicle is turning. Therefore, by solving the radius in the perpendicular direction between the turning geometric triangle and the forward tangent of the tire, the effective turning radius of the vehicle under steady-state turning can be obtained.

[0098] In an exemplary embodiment, please refer to Figure 11 , the effective turning radius calculation and prediction software unit may include a handlebar steering radius calculation logic, a body roll steering radius calculation logic, and an effective turning radius fusion calculation logic.

[0099] First, input the vehicle head steering angle, the wheelbase between the front and rear wheels, the parameters of the front steering mechanism, and the parameters of the front wheel tire size into the calculation logic of the handlebar steering radius for geometric calculation to obtain the handlebar steering radius. At the same time, input the wheel roll angle and the parameters of the rear wheel tire size into the calculation logic of the body roll steering radius for geometric calculation to obtain the body roll steering radius, which can improve the real-time performance of the effective turning radius detection. Then, input the handlebar steering radius and the body roll steering radius into the calculation logic of the effective turning radius fusion for rotation coordinate transformation in three-dimensional space, three-dimensional transformation matrix operation, and orthogonal projection onto the vehicle kinematic coordinate system to determine the turning geometric triangle. Solve according to the vertical direction radius of the turning geometric triangle and the forward tangent to obtain the effective turning radius in the motorcycle kinematic coordinate system, which can improve the accuracy of the effective turning radius, realize real-time and efficient dynamic monitoring and calculation of the effective turning radius of the motorcycle, and further be used for path prediction of higher-order motorcycle intelligent driving functions, safe driving, etc.

[0100] Please refer to Figure 12 , Figure 12 which is a schematic flowchart of the third embodiment of the vehicle turning radius detection method of this application. The method includes the following steps:

[0101] Step S1201, obtain the vehicle head steering angle, wheel attitude parameters, and factory design parameters.

[0102] Step S1202, calculate the vehicle head steering angle and the factory design parameters to obtain the handlebar steering radius of the vehicle.

[0103] Step S1203, calculate the wheel attitude parameters and the factory design parameters to obtain the body roll steering radius of the vehicle.

[0104] Among them, the implementation manners and beneficial effects of step S1201 can be as described in step S101 or step S201 above. The implementation manners and beneficial effects of step S1202 can be as described in step S102 or step S202 above. The implementation manners and beneficial effects of step S1203 can be as described in step S103 or steps S203 and S204 above.

[0105] Step S1204, in response to the wheel attitude parameters satisfying the preset stability condition and the tire slip rate satisfying the preset limit condition, execute the step of fusing and calculating the handlebar steering radius and the body roll steering radius to obtain the effective turning radius of the vehicle.

[0106] As an exemplary example, since the effective turning radius is the turning radius of the vehicle under stable turning conditions, that is, non-slip conditions. Therefore, in this embodiment, wheel attitude parameters and tire slip ratio are used to judge the stability of the vehicle. When the wheel attitude parameters meet the stable conditions and the tire slip ratio meets the limit conditions, the vehicle controller confirms that the vehicle is in a stable turning state, and fuses and calculates the handlebar turning radius and the body roll turning radius to update the effective turning radius, thereby improving the accuracy of the effective turning radius detection.

[0107] Among them, the stable condition can be used to confirm that the vehicle is in a stable turning state, indicating that the vehicle does not roll over excessively. The limit condition can be used to confirm that the vehicle is in a stable turning state, indicating that the vehicle does not slip or lose traction.

[0108] In some embodiments, the wheel attitude parameters include the wheel pitch angle and the wheel yaw angle, and the tire slip ratio includes the front wheel slip ratio and the rear wheel slip ratio.

[0109] In some embodiments, in response to the wheel attitude parameters meeting the preset stable conditions and the tire slip ratio meeting the preset limit conditions, it includes: detecting that the wheel pitch angle is less than the preset body steady-state pitch angle limit, and determining that the wheel pitch angle meets the stable conditions. Detecting that the wheel yaw angle is less than the preset body steady-state yaw angle limit, and determining that the wheel yaw angle meets the stable conditions. Detecting that the front wheel slip ratio is less than the preset first body steady-state slip ratio, and determining that the front wheel slip ratio meets the limit conditions. Detecting that the rear wheel slip ratio is less than the preset second body steady-state slip ratio, and determining that the rear wheel slip ratio meets the limit conditions.

[0110] As an exemplary example, the body steady-state pitch angle limit can be set according to the design or safety requirements of the motorcycle, indicating the maximum wheel pitch angle allowed under stable driving or turning conditions. If it is detected that the wheel pitch angle is greater than or equal to the preset body steady-state pitch angle limit, it means that the front and rear tilting angles of the motorcycle are too large, and the vehicle may have entered an unstable state.

[0111] The body steady-state yaw angle limit can be set according to the design or safety requirements of the motorcycle, indicating the maximum wheel yaw angle allowed under stable driving or turning conditions. When it is detected that the wheel yaw angle is greater than or equal to the preset body steady-state yaw angle limit, it means that the wheel yaw angle of the motorcycle is too large, and the vehicle may be in a slipping or unstable state.

[0112] The first body steady-state slip ratio is used to indicate that when the vehicle is driving and turning normally, the slip of the rear wheel remains within a safe range. When it is detected that the front wheel slip ratio is greater than or equal to the preset steady-state limit, it means that the slip of the front wheel is too large, which may cause the front wheel to lose control or become unstable.

[0113] The second vehicle body steady-state slip ratio is used to indicate that when the vehicle is driving normally and turning, the slip of the rear wheels remains within a safe range. When it is detected that the rear-wheel slip ratio is greater than or equal to the preset steady-state limit value, it indicates that the rear-wheel tires may have lost sufficient traction, and situations such as skidding, fishtailing, or out-of-control may occur. Among them, the second vehicle body steady-state slip ratio can be equal to or different from the first vehicle body steady-state slip ratio.

[0114] Step S1205, in response to the wheel attitude parameters not meeting the stability condition and / or the tire slip ratio not meeting the limit condition, maintain the effective turning radius of the previous cycle.

[0115] As an exemplary example, when the wheel attitude parameters do not meet the stability condition or the tire slip ratio exceeds the limit condition, it indicates that the vehicle has entered an unstable state, such as vehicle skidding. When the vehicle is not in a stable state, to reduce the danger caused by the calculated turning radius deviating too much from the actual situation in the unstable state, the vehicle controller can maintain the effective turning radius calculated in the previous cycle.

[0116] In an exemplary embodiment, please refer to Figure 13 , the vehicle may include a front-wheel steering angle sensor hardware, an on-vehicle controller board-mounted six-axis IMU hardware, and an on-vehicle controller hardware. This embodiment is applied to the on-vehicle controller hardware of the vehicle, and the on-vehicle controller hardware may include: an Euler angle calculation software unit, an effective turning radius calculation and prediction software unit, and an on-vehicle slip ratio calculation software module.

[0117] When the vehicle is turning, the X-axis acceleration, Y-axis acceleration, Z-axis acceleration, X-axis angular velocity, Y-axis angular velocity, and Z-axis angular velocity can be obtained through the on-vehicle controller board-mounted six-axis IMU hardware, and this data is input into the Euler angle calculation software unit to obtain the wheel attitude parameters; the front-wheel steering angular velocity is obtained through the front-wheel steering angle sensor hardware; the factory design parameters of the vehicle are input through the upper computer; and the tire slip ratio is obtained through the on-vehicle slip ratio calculation software module.

[0118] Then, the front-wheel steering angle, wheel attitude parameters, tire slip ratio, and factory design parameters are input into the effective turning radius calculation and prediction software unit for processing, and the effective turning radius is output. Among them, please refer to Figure 14 , the effective turning radius calculation and prediction software unit includes a handlebar turning radius calculation logic and a vehicle body roll turning radius calculation logic.

[0119] Input the front-end steering angle, the wheelbase between the front and rear wheels, the parameters of the front steering mechanism, and the parameters of the front wheel tire size into the calculation logic of the handlebar steering radius for geometric calculation to obtain the handlebar steering radius; input the wheel roll angle and the parameters of the rear wheel tire size into the calculation logic of the body roll steering radius for geometric calculation to obtain the body roll steering radius, which can improve the real-time performance of the effective turning radius detection.

[0120] Then, input the handlebar steering radius and the body roll steering radius into the calculation logic of the effective turning radius fusion for rotation coordinate system transformation in three-dimensional space, three-dimensional transformation matrix operation, and orthogonal projection onto the vehicle kinematic coordinate system to determine the turning geometric triangle, and solve according to the vertical direction radius of the turning geometric triangle and the forward tangent to obtain the effective turning radius in the motorcycle kinematic coordinate system.

[0121] At this time, it is possible to detect whether the wheel pitch angle is greater than or equal to the body steady-state pitch angle limit value, detect whether the wheel yaw angle is greater than or equal to the body steady-state yaw angle limit value, detect whether the front wheel slip ratio is greater than or equal to the first body steady-state slip ratio, and detect whether the rear wheel slip ratio is greater than or equal to the second body steady-state slip ratio; if the wheel pitch angle is less than the body steady-state pitch angle limit value, then determine that the wheel pitch angle is stable; if the wheel yaw angle is less than the body steady-state yaw angle limit value, then determine that the wheel yaw angle is stable; if the front wheel slip ratio is less than the first body steady-state slip ratio, then determine that the front wheel slip ratio is within the limit value; if the rear wheel slip ratio is less than the second body steady-state slip ratio, then determine that the rear wheel slip ratio is within the limit value; then, detect whether the wheel pitch angle is stable, the wheel yaw angle is stable, the front wheel slip ratio is within the limit value, and the rear wheel slip ratio is within the limit value; if the wheel pitch angle is stable, the wheel yaw angle is stable, the front wheel slip ratio is within the limit value, and the rear wheel slip ratio is within the limit value, then update the currently calculated effective turning radius and output it in real time to other software units of the vehicle controller and the vehicle CAN bus for use by other modules; otherwise, keep the effective turning radius as the value of the previous cycle.

[0122] Thus, this embodiment uses the wheel attitude parameters and the tire slip ratio to judge the stability of the vehicle. When the wheel attitude parameters meet the stable conditions and the tire slip ratio meets the limit conditions, the vehicle controller confirms that the vehicle is in a stable turning state, fuses and calculates the handlebar steering radius and the body roll steering radius to update the effective turning radius, thereby improving the accuracy of the effective turning radius detection. When the wheel attitude parameters do not meet the stable conditions or the tire slip ratio does not meet the limit conditions, the danger caused by the calculated turning radius deviating too much from the actual situation in the unstable state of the vehicle is reduced.

[0123] Another technical solution adopted in this application is as follows: Provide a vehicle control method, which includes: obtaining the effective turning radius of the vehicle; wherein, the effective turning radius is obtained based on the vehicle turning radius detection method of any one of the above; and performing vehicle control based on the effective turning radius.

[0124] Please refer to Figure 15 , Figure 15 which is an exemplary structural block diagram of the electronic device of this application. As Figure 15 shown, the electronic device 1500 of this application may include a processor 1501 and a memory 1502, where communication between the processor 1501 and the memory 1502 is carried out through a bus. The memory 1502 stores program instructions for vehicle turning radius detection. When the program instructions are executed by the processor 1501, the above-mentioned processor is enabled to execute the above-mentioned relevant method steps to implement a vehicle turning radius detection method or a vehicle control method in the above-mentioned embodiments.

[0125] Please refer to Figure 16 , Figure 16 which is an exemplary structural block diagram of the computer-readable storage medium of this application. As Figure 16 shown, a computer program 1601 is stored in the computer-readable storage medium 1600. When the computer program 1601 runs on a computer, the computer is enabled to execute the above-mentioned relevant method steps to implement a vehicle turning radius detection method or a vehicle control method in the above-mentioned embodiments.

[0126] In the above solution, by obtaining the head steering angle, wheel attitude parameters and factory design parameters of the vehicle; calculating the handlebar turning radius of the vehicle by calculating the head steering angle and the factory design parameters; calculating the body roll turning radius of the vehicle by calculating the wheel attitude parameters and the factory design parameters; and performing a fusion calculation on the handlebar turning radius and the body roll turning radius to obtain the effective turning radius of the vehicle. By calculating the handlebar turning radius of the vehicle by calculating the head steering angle and the factory design parameters, and calculating the body roll turning radius of the vehicle by calculating the wheel attitude parameters and the factory design parameters, the front wheel steering angle and the wheel roll angle during steady-state turning of the vehicle can be considered simultaneously, and by performing a fusion calculation on the handlebar turning radius and the body roll turning radius, the real-time performance and accuracy of the effective turning radius detection of the motorcycle can be improved.

[0127] In several embodiments provided in the present application, it should be understood that the disclosed methods, electronic devices, and storage media can be implemented in other ways. For example, the device embodiments described above are merely illustrative. For example, the division of modules or units is only a logical function division. In actual implementation, there may be other division methods. For example, multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the displayed or discussed coupling, direct coupling, or communication connection between each other can be through some interfaces. The indirect coupling or communication connection of devices or units can be in electrical, mechanical, or other forms.

[0128] The units described as separate components may or may not be physically separated. The components shown as units may or may not be physical units, that is, they can be located in one place, or they can be distributed to multiple network units. Some or all of the units can be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0129] In addition, in each embodiment of the present application, each functional unit can be integrated in a processing unit, or each unit can exist physically alone, or two or more units can be integrated in one unit. The above-mentioned integrated units can be implemented in the form of hardware or in the form of software functional units.

[0130] If the integrated unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on such an understanding, the technical solution of the present application, in essence, or the part that contributes to the prior art, or all or part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to enable a computer device (which can be a personal computer, a server, or a network device, etc.) or a processor to execute all or part of the steps of the vehicle turning radius detection method described in each embodiment of the present application. The aforementioned storage medium includes: various media such as USB flash drives, mobile hard disks, read-only memories (ROM, Read-Only Memory), random access memories (RAM, Random Access Memory), magnetic disks, or optical discs that can store program codes.

[0131] The above is only the embodiment of the present application, and does not limit the patent scope of the present application. All equivalent structural or equivalent process transformations made by using the content of the specification and drawings of the present application, or directly or indirectly applied in other related technical fields, are equally included in the patent protection scope of the present application.

Claims

1. A method for detecting the turning radius of a vehicle, characterized in that, The vehicle turning radius detection method includes: Obtaining the head steering angle, wheel attitude parameters, and factory design parameters of the vehicle; Calculating the handlebar turning radius of the vehicle by calculating the head steering angle and the factory design parameters; Calculating the body roll turning radius of the vehicle by calculating the wheel attitude parameters and the factory design parameters; Performing a fusion calculation on the handlebar turning radius and the body roll turning radius to obtain the effective turning radius of the vehicle; The performing a fusion calculation on the handlebar turning radius and the body roll turning radius to obtain the effective turning radius of the vehicle includes: Taking the contact point between the rear wheel tire of the vehicle and the ground as the coordinate origin to construct a vehicle kinematics coordinate system; Performing a spatial transformation and projection operation on the handlebar turning radius and the body roll turning radius to obtain the turning parameters in the vehicle kinematics coordinate system; wherein, the turning parameters include the center coordinates of the handlebar turning radius, the converted handlebar turning radius, the center coordinates of the roll turning radius, and the converted body roll turning radius; Determining a turning geometric triangle according to the turning parameters and the coordinate origin; Solving the perpendicular direction radius of the turning geometric triangle and the tire forward tangent of the vehicle to obtain the effective turning radius.

2. The vehicle turning radius detection method according to claim 1, wherein The performing a spatial transformation and projection operation on the handlebar turning radius and the body roll turning radius to obtain the turning parameters in the vehicle kinematics coordinate system includes: Performing a rotation coordinate system transformation in a three-dimensional space, a three-dimensional transformation matrix operation, and an orthogonal projection onto the vehicle kinematics coordinate system on the handlebar turning radius and the body roll turning radius in sequence to obtain the turning parameters.

3. The vehicle turning radius detection method according to claim 1, wherein The determining a turning geometric triangle according to the turning parameters and the coordinate origin includes: Determining the origin position of the body roll turning radius below the ground plane and the origin position of the handlebar turning radius in the vehicle kinematics coordinate system according to the positions of the turning parameters and the coordinate origin; Determining the turning geometric triangle according to the position of the coordinate origin, the origin position of the body roll turning radius below the ground plane, and the origin position of the handlebar turning radius.

4. The vehicle turning radius detection method according to claim 1, characterized in that, The factory design parameters include the front and rear wheel wheelbase, the front steering mechanism parameters, and the front wheel tire size parameters; the calculating the handlebar turning radius of the vehicle by calculating the head steering angle and the factory design parameters includes: Performing a geometric operation on the head steering angle, the front and rear wheel wheelbase, the front steering mechanism parameters, and the front wheel tire size parameters to obtain the handlebar turning radius.

5. The vehicle turning radius detection method according to claim 1, wherein The wheel attitude parameters include the wheel roll angle, and the factory design parameters include the rear wheel tire size parameters; the calculating the body roll turning radius of the vehicle by calculating the wheel attitude parameters and the factory design parameters includes: Performing a geometric operation on the wheel roll angle and the rear wheel tire size parameters to obtain the actual ground contact rolling radius; Perform geometric operations on the actual grounding rolling radius and the wheel roll angle to obtain the body roll steering radius.

6. The vehicle turning radius detection method according to any one of claims 1 to 5, characterized in that, Before the step of fusing and calculating the handlebar steering radius and the body roll steering radius to obtain the effective turning radius of the vehicle, it includes: Obtain the tire slip rate of the vehicle; In response to the wheel attitude parameters satisfying the preset stability condition and the tire slip rate satisfying the preset limit condition, execute the step of fusing and calculating the handlebar steering radius and the body roll steering radius to obtain the effective turning radius of the vehicle; In response to the wheel attitude parameters not satisfying the stability condition and / or the tire slip rate not satisfying the limit condition, maintain the effective turning radius of the previous cycle.

7. The vehicle turning radius detection method according to claim 6, wherein, The wheel attitude parameters include the wheel pitch angle and the wheel yaw angle, and the tire slip rate includes the front wheel slip rate and the rear wheel slip rate; the response to the wheel attitude parameters satisfying the preset stability condition and the tire slip rate satisfying the preset limit condition includes: Detect that the wheel pitch angle is less than the preset body steady-state pitch angle limit, and determine that the wheel pitch angle satisfies the stability condition; Detect that the wheel yaw angle is less than the preset body steady-state yaw angle limit, and determine that the wheel yaw angle satisfies the stability condition; Detect that the front wheel slip rate is less than the preset first body steady-state slip rate, and determine that the front wheel slip rate satisfies the limit condition; Detect that the rear wheel slip rate is less than the preset second body steady-state slip rate, and determine that the rear wheel slip rate satisfies the limit condition.

8. A vehicle control method, characterized in that, The vehicle control method includes: Obtain the effective turning radius of the vehicle; wherein, the effective turning radius is obtained based on the vehicle turning radius detection method described in any one of claims 1 to 7; Perform vehicle control based on the effective turning radius.

9. An electronic device, characterized in that, The electronic device includes: A memory for storing executable program code; A processor for calling and running the executable program code from the memory, so that the electronic device executes the vehicle turning radius detection method described in any one of claims 1 to 7 or the vehicle control method described in claim 8.

10. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores a computer program, which when executed by a processor, implements the vehicle turning radius detection method described in any one of claims 1 to 7 or the vehicle control method described in claim 8.

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