Steering control method, device, control apparatus and vehicle for vehicle

Abstract

This application provides a vehicle steering control method, device, control equipment, and vehicle. The method includes: acquiring the vehicle's actual turning angle and target turning angle in the current cycle; determining dynamic response parameters within the current cycle based on the actual turning angle and target turning angle; wherein the dynamic response parameters characterize the inertial delay of the vehicle's steering system when performing steering; determining a first compensation turning angle based on the dynamic response parameters, the target turning angle, the target turning angle of the previous cycle, and a preset sampling time; wherein the previous cycle is the cycle adjacent to the current cycle; determining the turning angle control amount for the current cycle based on the first compensation turning angle and the target turning angle, and controlling the vehicle to steer according to the turning angle control amount. This method aims to improve the accuracy of the vehicle tracking a reference trajectory.

Description

Technical Field

[0001] This application relates to the field of vehicle technology, and in particular to a steering control method, device, control equipment, and vehicle for a vehicle. Background Technology

[0002] With the rapid development of science and technology, autonomous driving technology for vehicles is gradually emerging. Vehicles can generate a target turning angle based on a reference trajectory and control the vehicle's steering system to steer, thereby tracking the reference trajectory and achieving autonomous driving.

[0003] However, the vehicle's steering system may experience a response delay when receiving the target steering angle and executing the steering operation. This can lead to errors in the vehicle's tracking of the reference trajectory, causing the vehicle to deviate from the reference trajectory.

[0004] Therefore, there is an urgent need for a solution that enables vehicles to accurately track reference trajectories. Summary of the Invention

[0005] The vehicle steering control method, device, control equipment, and vehicle provided in this application are used to improve the accuracy of vehicle tracking reference trajectory.

[0006] In a first aspect, embodiments of this application provide a vehicle steering control method, comprising:

[0007] Obtain the vehicle's actual and target turning angles in the current cycle;

[0008] Based on the actual turning angle and the target turning angle, determine the dynamic response parameters within the current cycle; whereby the dynamic response parameters characterize the inertial delay of the vehicle's steering system when performing steering.

[0009] The first compensation angle is determined based on the dynamic response parameters, the target turning angle, the target turning angle of the previous cycle, and the preset sampling time; where the previous cycle is the cycle preceding the current cycle.

[0010] Based on the first compensation angle and the target angle, determine the angle control amount for the current cycle, and control the vehicle to steer according to the angle control amount.

[0011] In one possible implementation, determining the first compensation angle based on dynamic response parameters, the target rotation angle, the target rotation angle of the previous cycle, and a preset sampling time includes:

[0012] The sum of the target turning angle and the advance compensation amount is determined as the first compensation turning angle; wherein, the advance compensation amount is the product of the preset ratio and the turning angle difference, the preset ratio is the ratio of the dynamic response parameter to the preset sampling time, and the turning angle difference is the difference between the target turning angle and the target turning angle of the previous cycle.

[0013] In one possible implementation, determining the dynamic response parameters within the current cycle based on the actual turning angle and the target turning angle includes:

[0014] The input-output relationship between the actual rotation angle and the target rotation angle is iteratively fitted using the recursive least squares method to calculate the dynamic response parameters within the current cycle.

[0015] In one possible implementation, the method further includes:

[0016] If it is determined that the dynamic response parameter in the current period is greater than the upper limit of the preset parameter range, then the dynamic response parameter in the current period will be corrected to the upper limit.

[0017] If it is determined that the dynamic response parameter in the current period is less than the lower limit of the preset parameter range, then the dynamic response parameter in the current period is corrected to the lower limit.

[0018] The preset parameter range represents the allowable range of values ​​for the dynamic response parameters.

[0019] In one possible implementation, before determining the angle control amount for the current cycle based on the first compensated angle and the target angle, the method further includes:

[0020] Based on the actual turning angle and the target turning angle, determine the turning angle deviation within the current cycle; where the turning angle deviation is the difference between the target turning angle and the actual turning angle.

[0021] The second compensation angle is determined based on the angle deviation in the current cycle, the preset calculation parameters, and the angle deviation in the previous cycle; wherein, the angle deviation in the previous cycle is the difference between the target angle and the actual angle in the previous cycle.

[0022] In one possible implementation, determining the angle control amount for the current cycle based on the first compensated angle and the target angle includes:

[0023] The sum of the first compensation angle and the second compensation angle is determined as the total compensation angle;

[0024] The sum of the total compensation angle and the target angle is determined as the angle control value for the current cycle.

[0025] In one possible implementation, the preset calculation parameters include: proportional parameters, integral parameters, and differential parameters; the method further includes:

[0026] Based on the preset mapping relationship, the proportional parameter, integral parameter, and derivative parameter of the current period are determined according to the dynamic response parameters in the current period; wherein, the preset mapping relationship represents the proportional parameter, integral parameter, and derivative parameter corresponding to different dynamic response parameters.

[0027] Secondly, embodiments of this application provide a vehicle steering control device, comprising:

[0028] The acquisition module is used to acquire the vehicle's actual turning angle and target turning angle in the current cycle;

[0029] The processing module is used to determine the dynamic response parameters in the current cycle based on the actual steering angle and the target steering angle; wherein, the dynamic response parameters characterize the inertial delay of the vehicle's steering system when performing steering.

[0030] The processing module is also used to determine the first compensation angle based on the dynamic response parameters, the target angle, the target angle of the previous cycle, and the preset sampling time; wherein, the previous cycle is the cycle adjacent to the current cycle.

[0031] The processing module is also used to determine the angle control amount for the current cycle based on the first compensation angle and the target angle.

[0032] The control module is used to control the vehicle to steer according to the steering angle control amount.

[0033] In one possible implementation, the first compensation angle is determined based on the dynamic response parameters, the target rotation angle, the target rotation angle of the previous cycle, and the preset sampling time. The processing module is used to:

[0034] The sum of the target turning angle and the advance compensation amount is determined as the first compensation turning angle; wherein, the advance compensation amount is the product of the preset ratio and the turning angle difference, the preset ratio is the ratio of the dynamic response parameter to the preset sampling time, and the turning angle difference is the difference between the target turning angle and the target turning angle of the previous cycle.

[0035] In one possible implementation, the dynamic response parameters for the current cycle are determined based on the actual turning angle and the target turning angle. The processing module is used to:

[0036] The input-output relationship between the actual rotation angle and the target rotation angle is iteratively fitted using the recursive least squares method to calculate the dynamic response parameters within the current cycle.

[0037] In one possible implementation, the processing module is further configured to:

[0038] If it is determined that the dynamic response parameter in the current period is greater than the upper limit of the preset parameter range, then the dynamic response parameter in the current period will be corrected to the upper limit.

[0039] If it is determined that the dynamic response parameter in the current period is less than the lower limit of the preset parameter range, then the dynamic response parameter in the current period is corrected to the lower limit.

[0040] The preset parameter range represents the allowable range of values ​​for the dynamic response parameters.

[0041] In one possible implementation, before determining the angle control amount for the current cycle based on the first compensated angle and the target angle, the processing module is further configured to:

[0042] Based on the actual turning angle and the target turning angle, determine the turning angle deviation within the current cycle; where the turning angle deviation is the difference between the target turning angle and the actual turning angle.

[0043] The second compensation angle is determined based on the angle deviation in the current cycle, the preset calculation parameters, and the angle deviation in the previous cycle; wherein, the angle deviation in the previous cycle is the difference between the target angle and the actual angle in the previous cycle.

[0044] In one possible implementation, the angle control amount for the current cycle is determined based on the first compensated angle and the target angle, and the processing module is used to:

[0045] The sum of the first compensation angle and the second compensation angle is determined as the total compensation angle;

[0046] The sum of the total compensation angle and the target angle is determined as the angle control value for the current cycle.

[0047] In one possible implementation, the preset calculation parameters include: proportional parameters, integral parameters, and differential parameters; the processing module is further configured to:

[0048] Based on the preset mapping relationship, the proportional parameter, integral parameter, and derivative parameter of the current period are determined according to the dynamic response parameters in the current period; wherein, the preset mapping relationship represents the proportional parameter, integral parameter, and derivative parameter corresponding to different dynamic response parameters.

[0049] Thirdly, embodiments of this application provide a control device, including: a memory and a processor;

[0050] The memory stores instructions that the computer executes;

[0051] The processor executes computer execution instructions stored in memory, causing the processor to perform the first aspect and / or various possible implementations of the first aspect as described above.

[0052] Fourthly, embodiments of this application provide a vehicle including a control device for performing the first aspect and / or various possible implementations of the first aspect.

[0053] Fifthly, embodiments of this application provide a computer-readable storage medium storing computer-executable instructions, which, when executed by a processor, are used to implement the first aspect and / or various possible implementations of the first aspect.

[0054] In a sixth aspect, embodiments of this application provide a computer program product, including a computer program that, when executed by a processor, implements the first aspect and / or various possible implementations of the first aspect.

[0055] The vehicle steering control method, device, control equipment, and vehicle provided in this application acquire the target angle and actual angle of the steering system periodically and in real time, and calculate the dynamic response parameters of the vehicle's steering system. Based on these dynamic response parameters, a first compensation angle is constructed to eliminate the angle delay caused by the dynamic response parameters of the steering system. Finally, based on the target angle and the first compensation angle, an angle control quantity is generated, and the vehicle steering is controlled based on the angle control quantity. This reduces the angle delay caused by the dynamic response parameters of the steering system, reduces the tracking error between the vehicle and the target angle during actual steering, and thus improves the accuracy of the vehicle tracking the reference trajectory. Attached Figure Description

[0056] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of this application.

[0057] Figure 1 Flowchart of the vehicle steering control method provided in this application Figure 1 ;

[0058] Figure 2 Flowchart of the vehicle steering control method provided in this application Figure 2 ;

[0059] Figure 3 A schematic diagram of the steering control device for the vehicle provided in this application;

[0060] Figure 4 A schematic diagram of the control device provided in this application.

[0061] The accompanying drawings illustrate specific embodiments of this application, which will be described in more detail below. These drawings and descriptions are not intended to limit the scope of the concept in any way, but rather to illustrate the concept of this application to those skilled in the art through reference to particular embodiments. Detailed Implementation

[0062] Exemplary embodiments will now be described in detail, examples of which are illustrated in the accompanying drawings. When the following description relates to the drawings, unless otherwise indicated, the same numbers in different drawings denote the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with this application. Rather, they are merely examples of apparatuses and methods consistent with some aspects of this application as detailed in the appended claims.

[0063] First, let me explain the terms used in this application:

[0064] Dynamic response parameters are parameters that characterize the inertial delay of a vehicle's steering system. Specifically, dynamic response parameters can refer to the time constant. For example, the value of the time constant changes dynamically with factors such as vehicle speed, steering angle, and component wear.

[0065] Recursive Least Squares (RLS) is an online adaptive parameter estimation algorithm used to optimize linear model parameters in real time. It minimizes the sum of weighted squared errors between predicted and observed values ​​through recursion, without recalculating all historical data, and updates the current result based only on the estimate from the previous time step.

[0066] Proportional, integral, and derivative parameters refer to the operational parameters of different computational stages in the proportional-integral-derivative (PID) control process. The PID control algorithm is a classic closed-loop feedback control algorithm. It uses a combination of proportional (P), integral (I), and derivative (D) operations to adjust the control input in real time based on the deviation between the actual output value and the target reference value, thereby eliminating the deviation and stabilizing the system.

[0067] With the rapid development of science and technology, autonomous driving technology for vehicles is gradually evolving. In an autonomous driving system, the perception system equipped in the vehicle can acquire environmental information and generate a reference trajectory for the target through the decision-making system. The vehicle's underlying actuators then track this reference trajectory. Specifically, these underlying actuators can include the steering system, braking system, and drive system. The vehicle can generate a target turning angle based on the reference trajectory. Based on this target turning angle, the vehicle's steering system is controlled to steer, thereby tracking the reference trajectory and achieving autonomous driving.

[0068] It is understandable that the dynamic response characteristics of a vehicle's steering system directly affect the degree of matching between the vehicle's actual driving path and the target path. In real-world driving scenarios, the dynamic response delay of the steering motor and transmission mechanism, as well as insufficient response of the vehicle's steering system, can lead to problems with the accuracy and stability of the vehicle's trajectory tracking.

[0069] In some embodiments, compensation methods for steering delays in vehicles can be implemented using fixed-parameter models or offline identification strategies. For example, the steering system delay can be modeled as a first-order inertial element with a fixed time constant, and a feedforward compensator can be designed based on this model. However, in real-world driving scenarios, the steering system delay can vary due to component wear and environmental changes. The compensation effect of fixed-time-constant schemes decays over time, leading to decreased steering control accuracy and trajectory tracking accuracy.

[0070] Based on the above scenarios, it can be seen that the relevant technologies have a technical problem of large tracking error between the actual turning angle and the target turning angle of the vehicle's steering system, resulting in low tracking accuracy of the vehicle's reference trajectory.

[0071] The vehicle steering control method provided in this application periodically acquires the target angle and actual angle of the steering system in real time, and calculates the dynamic response parameters of the vehicle's steering system. Based on these dynamic response parameters, a first compensation angle is constructed to eliminate the angle delay caused by the dynamic response parameters of the steering system. Finally, based on the target angle and the first compensation angle, an angle control quantity is generated, and the vehicle steering is controlled based on the angle control quantity. This reduces the angle delay caused by the dynamic response parameters of the steering system, reduces the tracking error between the vehicle and the target angle during actual steering, and thus improves the accuracy of the vehicle in tracking the reference trajectory.

[0072] The technical solution of this application and how it solves the above-mentioned technical problems will be described in detail below with specific embodiments. These specific embodiments can be combined with each other, and the same or similar concepts or processes may not be described again in some embodiments. The embodiments of this application will be described below with reference to the accompanying drawings.

[0073] Figure 1 Flowchart of the vehicle steering control method provided in this application Figure 1 ,like Figure 1 As shown, the method includes:

[0074] Step 101. Obtain the vehicle's actual turning angle and target turning angle in the current cycle.

[0075] For example, the vehicle's actual steering angle and target steering angle are acquired periodically. The target steering angle is a target steering angle generated based on a reference trajectory that the vehicle needs to follow, used to guide the vehicle's actual steering actions. The actual steering angle is the steering angle actually output by the vehicle's steering system, measured by sensors.

[0076] Step 102. Determine the dynamic response parameters within the current cycle based on the actual turning angle and the target turning angle.

[0077] Among them, the dynamic response parameter characterizes the inertial delay of the vehicle's steering system when performing steering.

[0078] For example, based on the actual and target steering angles within the current cycle, an online identification algorithm can fit the dynamic response parameters for the current cycle. These dynamic response parameters characterize the inertial delay in the vehicle's steering system during steering. Specifically, the dynamic response parameters are time constants. Optionally, the online identification algorithm can be a recursive least squares method.

[0079] It can be understood that the actual and target steering angles of the vehicle in the current cycle are obtained as input to the online parameter identification algorithm. The online parameter identification algorithm can then calculate the time constant of the steering system in the current cycle in real time using the actual and target steering angles.

[0080] It should be noted that the relationship between the steering wheel's response angle and the assist torque of the electric power steering (EPS) motor is related to the EPS's assist curve. Furthermore, there is a non-linear correlation between the assist curve and vehicle speed, and similarly, there is a non-linear relationship between the steering wheel's response angle (or response torque) and the requested angle (or requested torque). Therefore, it can be understood that the steering wheel's response angle (i.e., the aforementioned actual angle) is related to both vehicle speed and the requested angle (i.e., the aforementioned target angle).

[0081] Furthermore, the vehicle's steering system can be constructed as a first-order inertial element model. The transfer function of the first-order inertial element model can be expressed as:

[0082] (1)

[0083] in, This represents the time constant, which is not a fixed value; it is related to the vehicle speed. and the target corner This is relevant. It indicates that the steering system's response changes dynamically depending on the operating conditions. This represents the Laplace operator.

[0084] Based on this, the delay in the steering system causes a deviation between the actual steering angle and the target steering angle, which can be expressed as:

[0085] (2)

[0086] in, Indicates the actual turning angle. Indicates the target turning point. This represents the transfer function of a first-order inertial element model of a steering system that includes a time constant. It should be noted that...

[0087] It is understandable that the existence of a time constant causes a delay in the steering system, resulting in a deviation between the actual and target steering angles of the vehicle. Therefore, within the current cycle, obtaining the target and actual steering angles within the current cycle can be achieved through fitting. The time constant in the process. It should be noted that since the transfer function is in the form of a Laplace transform, when actually performing the fitting, it is necessary to obtain the target rotation angle and the actual rotation angle within the current cycle, perform a Laplace transform on them, and then perform fitting to obtain the time constant within the current cycle.

[0088] Step 103. Determine the first compensation angle based on the dynamic response parameters, the target rotation angle, the target rotation angle of the previous cycle, and the preset sampling time.

[0089] The previous cycle refers to the cycle preceding the current cycle.

[0090] For example, as can be seen from step 102 above, the delay in the steering system causes a deviation between the actual steering angle and the target steering angle. Using the transfer function of the first-order inertial element model of the steering system, a dynamic feedforward compensator can be constructed. The transfer function of this dynamic feedforward compensator is similar to the transfer function of the steering system. They are reciprocals of each other. That is, the feedforward compensator is the inverse of the steering system model. This can be expressed by the following formula:

[0091] (3)

[0092] in, This represents the transfer function of the feedforward compensator. is the time constant.

[0093] It should be noted that the transfer function of the feedforward compensator mentioned above is a continuous function. By discretizing it, the first compensation angle for the current period can be determined.

[0094] It can be understood that the value of the transfer function of the feedforward compensator multiplied by the transfer function of the steering compensator is 1. Combining the above formula (2), it can be seen that the actual steering angle output at this time is the target steering angle, thus realizing the accurate tracking of the target steering angle by the actual steering angle.

[0095] Specifically, the first compensation angle of the current cycle can be calculated using the target angle of the current cycle, the time constant of the current cycle, the preset sampling time, and the target angle of the previous cycle. The specific calculation formula can be found in the embodiments described below.

[0096] Step 103 yields the first compensation angle for the current cycle, which is used to feedforward the target angle and proactively provide the steering system with an advance amount to counteract the inertial delay of the steering system.

[0097] Step 104. Based on the first compensation angle and the target angle, determine the angle control amount for the current cycle, and control the vehicle to steer according to the angle control amount.

[0098] For example, the first compensated steering angle is superimposed on the actual steering angle to obtain the steering angle control value for the current cycle. Since the first compensated steering angle can offset the inertial delay caused by the time constant in the steering system, the first compensated steering angle is superimposed on the actual steering angle to eliminate the aforementioned delay, thereby obtaining the steering angle control value.

[0099] It is understandable that this steering angle control quantity is the final instruction sent to the actuator of the steering system, indicating the final angle at which the vehicle should turn.

[0100] The vehicle steering control method provided in this application obtains the dynamic response parameters of the vehicle's steering system by periodically acquiring the target and actual steering angles of the steering system in real time and then fitting and calculating them. This method continuously captures changes in the dynamic response characteristics of the steering system, overcoming the limitation of fixed models in related technologies that cannot adapt to dynamic changes.

[0101] Based on these dynamic response parameters, a first compensation angle is constructed to eliminate the angular delay caused by the dynamic response parameters of the steering system. Finally, based on the target angle and the first compensation angle, an angle control quantity is generated, and the vehicle's steering is controlled based on this quantity. This reduces the angular delay caused by the dynamic response parameters of the steering system, decreases the tracking error between the vehicle and the target angle during actual steering, and thus improves the accuracy of the vehicle in tracking the reference trajectory.

[0102] As can be seen from the foregoing embodiments, the dynamic response parameters within each cycle can offset the inertial delay of the steering system. Specifically, the target steering angle can be compensated by designing a lead compensation amount, thereby obtaining the first compensated steering angle.

[0103] Specifically, in one example, in step 103 above, determining the first compensation angle based on the dynamic response parameters, the target rotation angle, the target rotation angle of the previous cycle, and the preset sampling time includes:

[0104] The sum of the target turning angle and the advance compensation amount is determined as the first compensation turning angle.

[0105] The advance compensation amount is the product of the preset ratio and the angle difference. The preset ratio is the ratio of the dynamic response parameter to the preset sampling time, and the angle difference is the difference between the target angle and the target angle of the previous cycle.

[0106] For example, the calculation method for the first compensation angle can be expressed by the following formula:

[0107] (4)

[0108] in, This indicates the first compensation turning point of the current cycle. Indicates the target turning angle for the current cycle. This indicates the target turning angle of the previous cycle, which is understandable. This is the difference in angle. This represents the time constant of the current period. This indicates the preset sampling time, which is understandable. This is the preset ratio.

[0109] Using the above formula, the first compensation angle for the current cycle can be calculated based on the time constant fitted in the current cycle, the target angle for the current cycle, the preset sampling time, and the target angle for the previous cycle. This first compensation angle is then superimposed with the target angle for the current cycle to obtain the angle control value for the current cycle. Controlling the steering system's actuators based on this angle control value reduces angle deviation caused by steering system delays and minimizes trajectory tracking deviations.

[0110] In the example above, the inverse model concept is used to determine a first compensation angle to offset the inertial delay of the steering system. Based on this first compensation angle, the steering system can quickly reproduce and track the target angle after receiving a command, avoiding trajectory deviation caused by the steering system's delay. This improves the steering system's response speed while reducing error accumulation due to latency, achieving more precise trajectory tracking.

[0111] Based on the aforementioned embodiments, the time constant of the steering system can be fitted using an iterative optimization algorithm.

[0112] In one possible implementation, step 102 above, determining the dynamic response parameters within the current cycle based on the actual turning angle and the target turning angle, includes:

[0113] The input-output relationship between the actual rotation angle and the target rotation angle is iteratively fitted using the recursive least squares method to calculate the dynamic response parameters within the current cycle.

[0114] For example, Recursive Least Squares (RLS) is an online parameter identification algorithm that minimizes prediction error by iteratively updating model parameters. Specifically, it updates the estimates of dynamic response parameters (such as the time constant) by calculating the error vector and covariance matrix for the current period.

[0115] Based on the target and actual turning angles for the current cycle, the recursive least squares (RLS) method minimizes the prediction error through iterative calculation, dynamically fitting the input-output relationship of the steering system. Its core is to establish a discrete mathematical model describing the relationship between the system input and output, update the parameters of this model using RLS, and then solve for the time constant for the current cycle. .

[0116] Specifically, the vehicle speed in the current cycle is first introduced. As an influence on the time constant The key state variables are the vehicle speed and the target steering angle. This is because the response characteristics of the steering system are related to the vehicle speed and the target steering angle.

[0117] Combining formulas (1) and (2) above, the time constant is discretized to obtain the difference equation:

[0118] (5)

[0119] in, Indicates the actual turning angle of the current cycle. This indicates the angle control value of the previous cycle. and These are time-varying discrete parameters, whose values ​​are determined by the instantaneous dynamic characteristics of the system under the current operating conditions, i.e., the time constant of the current period. The time constant of the current cycle is determined by this. And based on the vehicle speed in the current cycle It is determined by the angle control amount of the previous cycle.

[0120] The update step of the RLS algorithm is executed to calculate the time constant of the current period. The specific steps are as follows:

[0121] Equation (5) can be rearranged into a linearly parameterized form as follows:

[0122] (6)

[0123] in, It is a data vector composed of historical data. The parameter vector to be identified.

[0124] In each cycle The iterative steps of the RLS algorithm are executed to obtain the time constant for each period; specifically, the following steps are included:

[0125] Calculate the gain matrix: ;

[0126] Calculate the prediction error: ;

[0127] Update parameter estimates: ;

[0128] Update the covariance matrix: .

[0129] in, Let be the covariance matrix of the previous period. Let be the covariance matrix for the current period. Forgetting factor ( ). It is the identity matrix. These are the parameter estimates after the current period update.

[0130] Based on discrete parameters , With continuous time constant The relation can be solved inversely to obtain the solution. The estimated value At this time Essentially A momentary observation that automatically incorporates vehicle speeds from the current period. and the angle control amount of the previous cycle Impact on system dynamics.

[0131] Optionally, when the vehicle steering control method provided in this application begins execution, it may also include system initialization operations. System initialization includes initializing the initial parameters of the RLS algorithm. Specifically, it sets the initial parameters of the Recursive Least Squares (RLS) algorithm, including but not limited to: initial values ​​of the parameter vector. Initial values ​​of the covariance matrix Forgetting factors Sampling time .

[0132] Furthermore, since the time constant obtained by fitting the current period may not conform to the actual application scenario during the calculation of the dynamic response parameters, it is necessary to check the rationality of the time constant obtained by fitting the calculation.

[0133] Optionally, the method also includes:

[0134] If it is determined that the dynamic response parameter in the current period is greater than the upper limit of the preset parameter range, then the dynamic response parameter in the current period will be corrected to the upper limit.

[0135] If it is determined that the dynamic response parameter in the current period is less than the lower limit of the preset parameter range, then the dynamic response parameter in the current period is corrected to the lower limit.

[0136] The preset parameter range represents the allowable range of values ​​for the dynamic response parameters.

[0137] For example, setting a time constant reasonable range If the RLS output If it exceeds this range, then .

[0138] It can be understood that the above reasonable range is the allowable numerical range of the dynamic response parameter. If the dynamic response parameter (time constant in the current period) is greater than the upper limit of the allowable numerical range, then the dynamic response parameter in the current period will be corrected to that upper limit. Combining this with the above formula, it can be understood that if... Greater than ,but The calculation result is Furthermore, The calculation result is .

[0139] If the dynamic response parameter (time constant) in the current period is less than the lower limit of the allowable range, then the dynamic response parameter in the current period will be corrected to that lower limit. Combining this with the above formula, it can be understood that if... Less than ,but The calculation result is Furthermore, The calculation result is .

[0140] In the above embodiments, the iterative fitting mechanism of recursive least squares can improve the identification accuracy and real-time performance of dynamic response parameters, such as time constant. For example, the RLS algorithm can quickly capture the fluctuation of the time constant of the steering system caused by mechanical inertia, obtain a more accurate time constant for the current cycle, obtain a more accurate first compensation angle, and reduce trajectory tracking errors caused by fixed parameters or parameter updates.

[0141] Furthermore, by setting a preset parameter range, the time constant obtained by the RLS algorithm is limited to the upper and lower limits of the preset parameter range, ensuring that the time constant closely matches the actual driving scenario and is more reasonable. This further improves the accuracy of determining the first compensation steering angle.

[0142] Figure 2 Flowchart of the vehicle steering control method provided in this application Figure 2 ,like Figure 2 As shown, in this embodiment... Figure 1 Based on the embodiments, the vehicle steering control method is further described in detail. Before determining the steering angle control amount for the current cycle based on the first compensation steering angle and the target steering angle, the method further includes:

[0143] Step 201. Determine the angle deviation within the current cycle based on the actual angle and the target angle.

[0144] Among them, the turning angle deviation is the difference between the target turning angle and the actual turning angle.

[0145] For example, based on the actual turning angle and the target turning angle within the current cycle, the difference between the target turning angle and the actual turning angle is determined as the turning angle deviation within the current cycle. This can be expressed by the following formula:

[0146] (7)

[0147] in, This represents the rotation angle deviation for the current cycle. The target turning point for the current cycle, This represents the actual turning angle of the current cycle.

[0148] Step 202. Determine the second compensation angle based on the angle deviation in the current cycle, the preset calculation parameters, and the angle deviation in the previous cycle.

[0149] The rotation angle deviation of the previous cycle is the difference between the target rotation angle and the actual rotation angle of the previous cycle.

[0150] For example, the second compensation angle is calculated by combining the angle deviation of the current cycle and the angle deviation of the previous cycle through PID control.

[0151] Specifically, PID control involves multiple calculation stages, each with different calculation parameters. The second compensation angle for the current cycle, calculated by PID control, can be expressed by the following formula:

[0152] (8)

[0153] in, This indicates the second compensation turn in the current cycle. This indicates the angle deviation in the current cycle. This indicates the angular deviation in the previous cycle. , and All of these are calculation parameters.

[0154] In the above embodiments, the first compensation angle in the aforementioned embodiments is used to achieve feedforward, which is responsible for eliminating large deviations from the target angle. Furthermore, the second compensation angle can be generated through PID control. The second compensation angle is used for feedback, which is responsible for stabilizing the actual angle to reach the target angle and eliminating small deviations.

[0155] Based on the above embodiments, since the second compensation angle for feedback compensation is calculated, it can be combined with the first compensation angle for feedforward compensation calculated in the previous embodiments to jointly compensate the target angle, thereby further improving the tracking accuracy between the actual angle and the target angle.

[0156] Specifically, in Figure 2 Based on the illustrated embodiment, step 104 determines the angle control amount for the current cycle according to the first compensation angle and the target angle, including:

[0157] The sum of the first compensation angle and the second compensation angle is determined as the total compensation angle; the sum of the total compensation angle and the target angle is determined as the angle control value for the current cycle.

[0158] For example, the total compensated steering angle can be calculated using the following formula:

[0159] (9)

[0160] in, This indicates the total compensation angle for the current cycle. This indicates the first compensation turning point of the current cycle. This indicates the second compensation turn in the current cycle.

[0161] Furthermore, the angle control value for the current cycle can be calculated using the following formula:

[0162] (10)

[0163] in, This indicates the angle control value for the current cycle. Indicates the target turning angle for the current cycle. This indicates the total compensation angle for the current cycle.

[0164] Furthermore, The information is sent to the actuators of the steering system to control the vehicle to steer with that steering control amount.

[0165] Furthermore, the target turning angle and the turning angle deviation for the current cycle are updated with historical data for the next cycle's calculation. , By repeatedly executing the above process, precise and adaptive compensation for vehicle steering delay can be achieved, ensuring high-quality path tracking performance.

[0166] In the example above, by combining the first compensation angle used for feedforward and the second compensation angle used for feedback, the total compensation angle superimposed on the target angle within the current cycle can be obtained, thus yielding an angle control quantity that enables the actual angle to quickly and stably track the target angle. Controlling the vehicle's steering system based on this angle control quantity can improve the tracking accuracy and stability of the vehicle's steering system.

[0167] As illustrated by the preceding examples, determining the second compensation angle requires the introduction of preset calculation parameters. In one possible implementation, the second compensation angle can be calculated using PID control.

[0168] Optional, preset calculation parameters include: proportional parameters, integral parameters, and derivative parameters.

[0169] As shown in the previous examples, For the proportional parameter in the calculation parameters, For the integral parameter in the calculation parameters, These are the differential parameters in the calculation parameters.

[0170] Based on this, the method also includes:

[0171] Based on the preset mapping relationship, the proportional parameter, integral parameter, and derivative parameter of the current period are determined according to the dynamic response parameters in the current period.

[0172] The preset mapping relationship represents the proportional parameter, integral parameter, and derivative parameter corresponding to different dynamic response parameters.

[0173] For example, based on the dynamic response parameters within the current period, i.e., the aforementioned time constant of the current period. Based on the preset mapping relationship, the values ​​of the proportional parameter, integral parameter and differential parameter are determined when calculating the second compensation angle in the current cycle.

[0174] The preset mapping relationship represents the values ​​of the proportional, integral, and differential parameters corresponding to different time constants. Therefore, based on the value of the time constant for the current period, the proportional, integral, and differential parameters corresponding to the current period can be determined.

[0175] Optionally, the mapping relationship can be in the form of a gain scheduling table. The gain scheduling table includes calculation parameters corresponding to different time constants, which can be used to determine the time constant of the current period. Determine the proportional parameter, integral parameter, and differential parameter corresponding to the current period, that is... , and .

[0176] Optionally, when the time constant is large, such as exceeding a preset threshold, the vehicle's steering system will have high inertia and slow response. In this case, the proportional coefficient can be appropriately reduced. This is to prevent oscillations. At the same time, the differential coefficient can be increased. To enhance the predictive damping of the system, suppress overshoot and oscillation, and reduce the integral coefficient To slow down the rate of points accumulation and improve stability.

[0177] Optionally, when the time constant is small, such as less than a preset threshold, the vehicle's steering system responds quickly. In this case, the proportional coefficient can be appropriately increased. and reduce the differential coefficients Maintain or appropriately increase This is to quickly eliminate steady-state errors.

[0178] It should be noted that the adjustment strategies for the calculation parameters indicated by different time constants in the above optional embodiments can be reflected in a mapping relationship. For example, the mapping relationship represents that when the time constant is greater than or equal to a preset threshold, the first proportional parameter, the first integral parameter, and the first differential parameter are determined. When the time constant is less than the preset threshold, the second proportional parameter, the second integral parameter, and the second differential parameter are determined. Specifically, the second proportional parameter is greater than the first proportional parameter, the second integral parameter is greater than or equal to the first integral parameter, and the second differential parameter is less than the first differential parameter.

[0179] It should be noted that, as illustrated in the foregoing examples, the vehicle steering control method provided in this application may also include system initialization operations upon execution. Furthermore, the system initialization operations may further include: establishing PID parameters and time constants. The mapping table (gain scheduling table) defines the time constant. The optimal corresponding to different intervals , and .

[0180] In the example above, determining the corresponding PID control parameters based on the time constant in the dynamic response parameters can improve the system's stability and robustness. Specifically, by selecting appropriate PID control parameters based on the time constant value, overshoot or slow response problems caused by fixed PID parameters can be avoided, ensuring that the vehicle's trajectory tracking maintains consistent performance under different operating conditions.

[0181] The vehicle steering control method provided in this application obtains the dynamic response parameters of the vehicle's steering system by periodically acquiring the target and actual steering angles of the steering system in real time and then fitting and calculating them. This method continuously captures changes in the dynamic response characteristics of the steering system, overcoming the limitation of fixed models in related technologies that cannot adapt to dynamic changes.

[0182] Based on these dynamic response parameters, a first compensation angle is constructed to eliminate the angular delay caused by the dynamic response parameters of the steering system. Finally, based on the target angle and the first compensation angle, an angle control quantity is generated, and the vehicle's steering is controlled based on this quantity. This reduces the angular delay caused by the dynamic response parameters of the steering system, decreases the tracking error between the vehicle and the target angle during actual steering, and thus improves the accuracy of the vehicle in tracking the reference trajectory.

[0183] The iterative fitting mechanism of recursive least squares improves the identification accuracy and real-time performance of dynamic response parameters, such as time constant. By limiting the time constant obtained by the RLS algorithm to within a preset parameter range, it ensures that the time constant closely matches the actual driving scenario, making it more reasonable. This further improves the accuracy of determining the first compensation steering angle.

[0184] By combining the first compensation angle used for feedforward and the second compensation angle used for feedback, the total compensation angle superimposed on the target angle within the current cycle can be obtained, thus yielding the angle control quantity that enables the actual angle to quickly and stably track the target angle. Controlling the vehicle's steering system based on this angle control quantity improves the system's tracking accuracy and stability. Furthermore, by determining the corresponding PID control parameters based on the time constant in the dynamic response parameters, the system's stability and robustness can be enhanced.

[0185] Figure 3 A schematic diagram of the steering control device for the vehicle provided in this application is shown below. Figure 3 As shown, the vehicle steering control device 30 provided in this embodiment includes:

[0186] The acquisition module 301 is used to acquire the vehicle's actual turning angle and target turning angle in the current cycle;

[0187] The processing module 302 is used to determine the dynamic response parameters in the current cycle based on the actual steering angle and the target steering angle; wherein, the dynamic response parameters characterize the inertial delay of the vehicle's steering system when performing steering.

[0188] The processing module 302 is also used to determine the first compensation angle based on the dynamic response parameters, the target angle, the target angle of the previous cycle, and the preset sampling time; wherein, the previous cycle is the cycle adjacent to the current cycle.

[0189] The processing module 302 is also used to determine the angle control amount for the current cycle based on the first compensation angle and the target angle;

[0190] The control module 303 is used to control the vehicle to steer according to the steering angle control amount.

[0191] In one possible implementation, the first compensation angle is determined based on the dynamic response parameters, the target rotation angle, the target rotation angle of the previous cycle, and the preset sampling time. The processing module 302 is used to:

[0192] The sum of the target turning angle and the advance compensation amount is determined as the first compensation turning angle; wherein, the advance compensation amount is the product of the preset ratio and the turning angle difference, the preset ratio is the ratio of the dynamic response parameter to the preset sampling time, and the turning angle difference is the difference between the target turning angle and the target turning angle of the previous cycle.

[0193] In one possible implementation, based on the actual turning angle and the target turning angle, the dynamic response parameters within the current cycle are determined, and the processing module 302 is used to:

[0194] The input-output relationship between the actual rotation angle and the target rotation angle is iteratively fitted using the recursive least squares method to calculate the dynamic response parameters within the current cycle.

[0195] In one possible implementation, the processing module 302 is further configured to:

[0196] If it is determined that the dynamic response parameter in the current period is greater than the upper limit of the preset parameter range, then the dynamic response parameter in the current period will be corrected to the upper limit.

[0197] If it is determined that the dynamic response parameter in the current period is less than the lower limit of the preset parameter range, then the dynamic response parameter in the current period is corrected to the lower limit.

[0198] The preset parameter range represents the allowable range of values ​​for the dynamic response parameters.

[0199] In one possible implementation, before determining the angle control amount for the current cycle based on the first compensated angle and the target angle, the processing module 302 is further configured to:

[0200] Based on the actual turning angle and the target turning angle, determine the turning angle deviation within the current cycle; where the turning angle deviation is the difference between the target turning angle and the actual turning angle.

[0201] The second compensation angle is determined based on the angle deviation in the current cycle, the preset calculation parameters, and the angle deviation in the previous cycle; wherein, the angle deviation in the previous cycle is the difference between the target angle and the actual angle in the previous cycle.

[0202] In one possible implementation, the angle control amount for the current cycle is determined based on the first compensated angle and the target angle, and the processing module 302 is used for:

[0203] The sum of the first compensation angle and the second compensation angle is determined as the total compensation angle;

[0204] The sum of the total compensation angle and the target angle is determined as the angle control value for the current cycle.

[0205] In one possible implementation, the preset calculation parameters include: proportional parameters, integral parameters, and differential parameters; the processing module 302 is further configured to:

[0206] Based on the preset mapping relationship, the proportional parameter, integral parameter, and derivative parameter of the current period are determined according to the dynamic response parameters in the current period; wherein, the preset mapping relationship represents the proportional parameter, integral parameter, and derivative parameter corresponding to different dynamic response parameters.

[0207] The vehicle steering control device provided in this embodiment can execute the method provided in the above method embodiment. Its implementation principle and technical effect are similar, and will not be described in detail here.

[0208] Figure 4 A schematic diagram of the control device provided in this application. Figure 4 As shown, the control device 40 provided in this embodiment includes at least one processor 401 and a memory 402. Optionally, the control device 40 further includes a communication component 403. The processor 401, memory 402, and communication component 403 are connected via a bus 404.

[0209] In a specific implementation, at least one processor 401 executes computer execution instructions stored in memory 402, causing at least one processor 401 to perform the above-described method.

[0210] The specific implementation process of processor 401 can be found in the above method embodiments, and its implementation principle and technical effect are similar. It will not be repeated here.

[0211] In the above embodiments, it should be understood that the processor can be a Central Processing Unit (CPU), or other general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), etc. The general-purpose processor can be a microprocessor or any conventional processor. The steps of the method disclosed in this invention can be directly implemented by a hardware processor, or implemented by a combination of hardware and software modules within the processor.

[0212] The memory may include random access memory (RAM) and may also include non-volatile memory (NVM), such as at least one disk storage device.

[0213] The bus can be an Industry Standard Architecture (ISA) bus, a Peripheral Component Interconnect (PCI) bus, or an Extended Industry Standard Architecture (EISA) bus, etc. Buses can be categorized as address buses, data buses, control buses, etc. For ease of illustration, the buses shown in the accompanying drawings are not limited to a single bus or a single type of bus.

[0214] This application also provides a vehicle. The vehicle includes the control device provided in the above embodiments. The control device is used to execute the vehicle steering control method provided in the foregoing method embodiments. Its implementation principle and technical effects are similar, and will not be described in detail here.

[0215] This application also provides a computer program product, including a computer program that, when executed by a processor, implements the above-described method.

[0216] This application also provides a computer-readable storage medium storing computer-executable instructions, which, when executed by a processor, implement the above-described method.

[0217] The aforementioned readable storage medium can be implemented by any type of volatile or non-volatile storage device or a combination thereof, such as static random access memory (SRAM), electrically erasable programmable read-only memory (EEPROM), erasable programmable read-only memory (EPROM), programmable read-only memory (PROM), read-only memory (ROM), magnetic storage, flash memory, magnetic disk, or optical disk. The readable storage medium can be any available medium accessible to a general-purpose or special-purpose computer.

[0218] An exemplary readable storage medium is coupled to a processor, enabling the processor to read information from and write information to the readable storage medium. Of course, the readable storage medium can also be a component of the processor. The processor and the readable storage medium can reside in an Application Specific Integrated Circuit (ASIC). Alternatively, the processor and the readable storage medium can exist as discrete components in the device.

[0219] The division of units is merely a logical functional division; in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the coupling or direct coupling or communication connection shown or discussed may be indirect coupling or communication connection through some interfaces, devices, or units, and may be electrical, mechanical, or other forms.

[0220] The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.

[0221] In addition, the functional units in the various embodiments of the present invention can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit.

[0222] If a function is implemented as a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of this invention, or the part that contributes to the prior art, or a 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 cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods of the various embodiments of this invention. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0223] Those skilled in the art will understand that all or part of the steps of the above-described method embodiments can be implemented by hardware related to program instructions. The aforementioned program can be stored in a computer-readable storage medium. When executed, the program performs the steps of the above-described method embodiments; and the aforementioned storage medium includes various media capable of storing program code, such as ROM, RAM, magnetic disks, or optical disks.

[0224] Finally, it should be noted that other embodiments of the invention will readily occur to those skilled in the art upon consideration of the specification and practice of the invention disclosed herein. This invention is intended to cover any variations, uses, or adaptations of the invention that follow the general principles of the invention and include common knowledge or customary techniques in the art not disclosed herein, and is not limited to the precise structures described above and shown in the accompanying drawings, and various modifications and changes can be made without departing from its scope. The scope of the invention is limited only by the appended claims.

Claims

1. A vehicle steering control method, characterized in that, include: Obtain the vehicle's actual and target turning angles in the current cycle; Based on the actual turning angle and the target turning angle, dynamic response parameters are determined within the current cycle; wherein, the dynamic response parameters characterize the inertial delay present in the vehicle's steering system when performing steering. The first compensation angle is determined based on the dynamic response parameters, the target rotation angle, the target rotation angle of the previous cycle, and the preset sampling time; wherein, the previous cycle is the cycle adjacent to the current cycle. Based on the first compensated steering angle and the target steering angle, the steering angle control amount for the current cycle is determined, and the vehicle is controlled to steer according to the steering angle control amount.

2. The method according to claim 1, characterized in that, Based on the dynamic response parameters, the target rotation angle, the target rotation angle of the previous cycle, and the preset sampling time, the first compensation rotation angle is determined, including: The sum of the target turning angle and the advance compensation amount is determined as the first compensation turning angle; wherein, the advance compensation amount is the product of a preset ratio and the turning angle difference, the preset ratio is the ratio of the dynamic response parameter to the preset sampling time, and the turning angle difference is the difference between the target turning angle and the target turning angle of the previous cycle.

3. The method according to claim 1, characterized in that, Based on the actual turning angle and the target turning angle, determine the dynamic response parameters within the current cycle, including: The input-output relationship between the actual rotation angle and the target rotation angle is iteratively fitted using the recursive least squares method to calculate the dynamic response parameters within the current cycle.

4. The method according to claim 3, characterized in that, The method further includes: If it is determined that the dynamic response parameter in the current period is greater than the upper limit of the preset parameter range, then the dynamic response parameter in the current period is corrected to the upper limit. If it is determined that the dynamic response parameter in the current period is less than the lower limit of the preset parameter range, then the dynamic response parameter in the current period is corrected to the lower limit. The preset parameter range represents the allowable numerical range of the dynamic response parameter.

5. The method according to any one of claims 1-4, characterized in that, Before determining the angle control amount for the current cycle based on the first compensated angle and the target angle, the method further includes: Based on the actual turning angle and the target turning angle, the turning angle deviation within the current cycle is determined; wherein, the turning angle deviation is the difference between the target turning angle and the actual turning angle; The second compensation angle is determined based on the angle deviation in the current cycle, the preset calculation parameters, and the angle deviation in the previous cycle; wherein the angle deviation in the previous cycle is the difference between the target angle and the actual angle in the previous cycle.

6. The method according to claim 5, characterized in that, Determining the angle control amount for the current cycle based on the first compensated angle and the target angle includes: The sum of the first compensation angle and the second compensation angle is determined as the total compensation angle; The sum of the total compensation angle and the target angle is determined as the angle control amount for the current cycle.

7. The method according to claim 5, characterized in that, The preset calculation parameters include: proportional parameters, integral parameters, and differential parameters; the method further includes: Based on a preset mapping relationship, the proportional parameter, integral parameter, and derivative parameter of the current period are determined according to the dynamic response parameters within the current period; wherein, the preset mapping relationship represents the proportional parameter, integral parameter, and derivative parameter corresponding to different dynamic response parameters.

8. A vehicle steering control device, characterized in that, include: The acquisition module is used to acquire the vehicle's actual turning angle and target turning angle in the current cycle; The processing module is used to determine dynamic response parameters within the current cycle based on the actual steering angle and the target steering angle; wherein the dynamic response parameters characterize the inertial delay of the vehicle's steering system when performing steering. The processing module is further configured to determine a first compensation angle based on the dynamic response parameters, the target angle, the target angle of the previous cycle, and a preset sampling time; wherein the previous cycle is the previous cycle adjacent to the current cycle. The processing module is further configured to determine the angle control amount of the current cycle based on the first compensated angle and the target angle; The control module is used to control the vehicle to steer according to the stated steering angle control amount.

9. A vehicle, characterized in that, Includes a control device for performing the method as described in any one of claims 1-7.

10. A computer program product, characterized in that, Includes a computer program that, when executed by a processor, implements the method of any one of claims 1-7.

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