A commercial vehicle lane keeping assist control method, system, device and medium considering road cross slope and cargo load bias

Abstract

The application relates to the technical field of lane keeping control, in particular to a commercial vehicle lane keeping auxiliary control method, system, equipment and medium considering road transverse slope and cargo load deviation, which comprises the following steps: acquiring vehicle operation data in real time, including lateral acceleration, vehicle speed, yaw rate, lateral position error and heading angle error; calculating equivalent lateral acceleration caused by road transverse slope and mapping the equivalent lateral acceleration into a transverse slope steering angle compensation amount; obtaining a steering instruction residual error by comparing an actual steering angle with an expected steering angle, and calculating a load deviation steering angle compensation amount; meanwhile, inputting the lateral position error and the heading angle error into a double-channel PID controller to obtain corresponding steering amounts; and finally linearly superimposing the transverse slope compensation amount, the load deviation compensation amount and the double-PID output amount to generate a final steering angle and control vehicle steering. The application can effectively identify and compensate continuous interference caused by road transverse slope and cargo load deviation, and improve the robustness and control stability of the lane keeping system.

Description

Technical Field

[0001] This application relates to the field of lane keeping control technology, specifically to a lane keeping auxiliary control method, system, device and medium for commercial vehicles that takes into account road cross slope and cargo off-center loading. Background Technology

[0002] Lane keeping assist systems, as a key technology for improving the active safety and driving comfort of commercial vehicles, play an important role in reducing vehicle departure accidents caused by driver fatigue or distraction. Due to their large size, long wheelbase, and variable loading conditions, commercial vehicles are more susceptible to the influence of road conditions and loading status during actual operation, placing higher demands on the robustness and adaptability of lane keeping control.

[0003] In existing technologies, lane keeping assist control for commercial vehicles typically employs a method based on visual sensors to detect lane lines, combined with feedback control strategies. Common solutions include using a PID (proportional-integral-derivative) controller to directly calculate steering commands based on lateral position errors to maintain the vehicle centered in the lane. Furthermore, to further improve control accuracy and handle complex dynamics, some solutions introduce model predictive control or advanced state estimation-based algorithms. These algorithms generate control commands by constructing a vehicle dynamics model and optimizing it online, attempting to better handle vehicle motion coupling and external disturbances.

[0004] However, existing lane keeping assist control schemes for commercial vehicles still have limitations in practical applications: traditional error feedback-based controllers, such as simple PID control, lack effective identification and dedicated compensation mechanisms for continuous static lateral force disturbances caused by road cross slopes and long-term vehicle center of gravity shifts caused by cargo eccentricity. The controller needs to continuously generate large steady-state outputs to counteract these disturbances, which can easily lead to integral saturation or overshoot, manifesting as the vehicle continuously deviating from the lane or exhibiting a low-frequency reciprocating correction "dragon-drawing" phenomenon. While advanced algorithms such as model predictive control can theoretically handle a variety of constraints and disturbances better, their computational complexity is high, demanding on the computing power of the onboard controller. Furthermore, the model parameter calibration is complex and the engineering implementation cost is high, making it difficult to widely deploy and apply in resource-constrained commercial vehicle controllers. Summary of the Invention

[0005] To address the technical problems of existing lane keeping assist control schemes for commercial vehicles, which suffer from poor control performance or complex and costly implementation when dealing with continuous disturbances such as road cross slope and cargo eccentricity, this application provides a lane keeping assist control method, system, device, and medium for commercial vehicles that takes into account road cross slope and cargo eccentricity. Through the synergy of feedforward compensation and dual-channel feedback, the robustness and adaptability of lane keeping under complex conditions are effectively improved with lower computational cost.

[0006] In a first aspect, this application provides a lane keeping assist control method for commercial vehicles that takes into account road cross slope and cargo eccentricity, comprising the following steps: S1. Real-time acquisition of vehicle operation data, including lateral acceleration, vehicle speed, yaw rate, lateral position error and heading angle error, where the lateral position error represents the lateral offset of the vehicle from the center of the lane, and the heading angle error represents the angle error between the vehicle's heading angle and the lane direction; S2. Calculate the equivalent lateral acceleration caused by the road cross slope based on lateral acceleration, vehicle speed and yaw rate, and map the equivalent lateral acceleration to the cross slope steering angle compensation amount; S3. Calculate the steering command residual caused by cargo eccentricity based on the comparison between the actual steering command and the expected steering angle, and calculate the eccentricity steering angle compensation amount based on the steering command residual; The desired steering angle is calculated based on the lateral position error and the heading angle error. S4. Input the lateral position error and heading angle error into the preset dual-channel PID controller, and output the position channel steering amount and heading channel steering amount; S5. Linearly superimpose the cross slope steering angle compensation, eccentric load steering angle compensation, position channel steering angle, and heading channel steering angle to output the final steering angle; S6. Generate steering commands based on the final steering angle and send them to the vehicle's steering actuator for execution.

[0007] It should be further noted that in step S1, the lateral acceleration is obtained by an inertial measurement unit (IMU) installed on the vehicle; Vehicle speed is obtained through a vehicle speed sensor installed on the vehicle; Yaw rate is obtained through a yaw rate sensor installed on the vehicle; Lateral position error and heading angle error are obtained through a vision system installed on the vehicle.

[0008] It should be further explained that the vehicle vision system identifies lane lines, calculates the lateral distance between the vehicle and the center of the lane as the lateral position error, and calculates the angle between the vehicle's heading angle and the lane direction as the heading angle error.

[0009] It should be further explained that step S2 specifically includes: Calculate the net lateral acceleration component :

[0010] in, Indicates lateral acceleration; Indicates vehicle speed; Indicates yaw rate; For the lateral acceleration component Low-pass filtering is performed to obtain the equivalent lateral acceleration. The formula is:

[0011] This indicates the cutoff frequency of the first low-pass filter. Equivalent lateral acceleration Mapped to cross slope turning angle compensation amount The formula is:

[0012] This represents the mapping coefficient calibrated through experiments.

[0013] It should be further noted that the cutoff frequency of the first low-pass filter processing... Set as Hz.

[0014] It should be further explained that the mapping coefficients The calibration was obtained through straight-line driving tests on roads with known cross slope angles or known equivalent lateral accelerations. Specifically: Record the constant front wheel steering angle required to maintain the vehicle's straight-line travel within the lane. And it is calculated according to the following formula: .

[0015] It should be further noted that in calibrating the mapping coefficients During the process, straight-line driving calibration experiments were conducted on roads with known cross slope angles. Then, the mapping coefficients corresponding to the required cross slope angles were obtained using linear interpolation. .

[0016] It should be further explained that step S3 specifically includes: Calculate the steering command residual The formula is:

[0017] in, Indicates the actual turning instruction; This indicates that the desired turning angle is calculated based on the lateral position error and the heading angle error. Steering command residual Low-pass filtering is performed to obtain the off-center steering angle compensation amount. The formula is:

[0018] This indicates the cutoff frequency for the second low-pass filter.

[0019] It should be further noted that the cutoff frequency of the second low-pass filter is... Set as Hz.

[0020] It should be further explained that its characteristic is, .

[0021] It should be further explained that the desired steering angle The steering angle is calculated using a pre-defined PID reference model. This model takes lateral position error and heading angle error as inputs to simulate the required steering angle under ideal conditions without road cross slope or cargo eccentricity interference, and uses this as the desired steering angle. Output.

[0022] It should be further noted that in step S4, the dual-channel PID controller includes a position channel and a heading channel: The position channel takes the lateral position error as input and outputs the position channel steering amount. The heading channel takes the heading angle error as input and outputs the heading channel turning amount.

[0023] It should be further explained that, in the position channel and heading channel, the proportional gain Kp, integral gain Ki, and derivative gain Kd of the PID controller are adjusted according to the vehicle speed and load status, and the adjustment rules are as follows: The higher the vehicle speed, the lower the proportional gain Kp, the lower the integral gain Ki, and the higher the derivative gain Kd. The fuller the vehicle load, the higher the proportional gain Kp, the higher the integral gain Ki, and the higher the derivative gain Kd.

[0024] It should be further noted that the formula for linear superposition in step S5 is:

[0025] in, Indicates the final steering angle; Indicates the position channel turning amount; Indicates the turning point of the heading channel; Indicates the amount of cross slope turning angle compensation; This indicates the amount of compensation for the off-center load steering angle; This indicates the preset heading channel weighting coefficient; This indicates the preset position channel weighting coefficient; This indicates the preset cross slope turning angle weighting coefficient; This indicates the preset weighting coefficient for the off-center load steering angle.

[0026] It should be further explained that the weighting coefficients , , , The following calibration method was used to determine the optimal control performance: Real-vehicle tests were conducted under different road cross slopes, uneven cargo loading, and vehicle speeds. The optimization objectives were lateral deviation accuracy and driving stability while maintaining lane position. The weighting coefficients were repeatedly adjusted until the optimal control effect was obtained, and the corresponding optimal weighting coefficients were used as the basis for determination. , , , The calibration value.

[0027] It should be further noted that in step S6, the steering command must meet safety restrictions, including steering gear angle limits and steering gear angle change rate limits.

[0028] It should be further noted that the security restrictions specifically include: When the vehicle speed is between 0 and 20 km / h, the steering gear angle limit is ±500°, and the steering gear angle change rate limit is 180° / s. That is, it is mandatory that the steering gear angle is [-500°, 500°] and the steering gear angle change rate is not higher than 180° / s. When the vehicle speed is between 20 and 40 km / h, the steering gear angle limit is ±400°, and the steering gear angle change rate limit is 150° / s. That is, it is mandatory that the steering gear angle is [-400°, 400°] and the steering gear angle change rate is not higher than 150° / s. When the vehicle speed is between 40 and 60 km / h, the steering gear angle limit is ±400°, and the steering gear angle change rate limit is 100° / s. That is, it is mandatory that the steering gear angle is [-400°, 400°] and the steering gear angle change rate is not higher than 100° / s. When the vehicle speed is in the range of 60 to 80 km / h, the steering gear angle limit is ±300°, and the steering gear angle change rate limit is 80° / s. That is, it is mandatory that the steering gear angle is [-300°, 300°] and the steering gear angle change rate is not higher than 80° / s. When the vehicle speed is between 80 and 100 km / h, the steering gear angle limit is ±100°, and the steering gear angle change rate limit is 50° / s. That is, it is mandatory that the steering gear angle is [-100°, 100°] and the steering gear angle change rate is not higher than 50° / s.

[0029] Secondly, this application provides a lane keeping assist control system for commercial vehicles that takes into account road cross slope and cargo eccentricity, for implementing the aforementioned lane keeping assist control method for commercial vehicles, including: The data acquisition module is used to acquire vehicle operation data in real time, including lateral acceleration, vehicle speed, yaw rate, lateral position error and heading angle error. The lateral position error represents the lateral offset of the vehicle from the center of the lane, and the heading angle error represents the angle error between the vehicle's heading angle and the lane direction. The cross slope compensation calculation module is used to calculate the equivalent lateral acceleration caused by the road cross slope based on lateral acceleration, vehicle speed and yaw rate, and map the equivalent lateral acceleration into cross slope steering angle compensation. The off-center load compensation calculation module is used to calculate the steering command residual caused by the off-center load based on the comparison between the actual steering command and the expected steering angle, and to calculate the off-center load steering angle compensation based on the steering command residual; wherein, the expected steering angle is calculated based on the lateral position error and the heading angle error; The dual-channel PID module is used to input the lateral position error and heading angle error into the preset dual-channel PID controller, and output the position channel steering amount and heading channel steering amount. The steering angle generation module is used to linearly superimpose the cross slope steering angle compensation, off-center load steering angle compensation, position channel steering, and heading channel steering to output the final steering angle. The special instruction generation and execution module is used to generate steering instructions based on the final steering angle and send them to the vehicle's steering actuator for execution.

[0030] Thirdly, this application provides an electronic device, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to implement the steps of the above-described commercial vehicle lane keeping assist control method.

[0031] Fourthly, this application provides a storage medium storing a computer program, which, when executed by a processor, implements the steps of the above-described commercial vehicle lane keeping assist control method.

[0032] As can be seen from the above technical solutions, this application has the following advantages: 1. This application acquires vehicle operation data in real time and comprehensively calculates the cross slope steering angle compensation and off-center load steering angle compensation. Combined with the output of a dual-channel PID controller based on lateral position error and heading angle error, the steering command is finally generated by linear superposition. This achieves targeted feedforward compensation and feedback control coordination for two types of continuous disturbances: road cross slope and cargo off-center load. It effectively reduces the output pressure of the controller under steady-state disturbances, solves the problem that traditional feedback control is difficult to simultaneously and efficiently suppress continuous static disturbances and dynamic tracking errors, and improves the comprehensive control performance and stability of the lane keeping system under complex working conditions.

[0033] 2. This application calculates the equivalent lateral acceleration caused by the road cross slope based on lateral acceleration, vehicle speed, and yaw rate, and maps it to the cross slope steering angle compensation. This can accurately identify and compensate for the gravitational force caused by the lateral inclination of the road, solving the problem that the controller in the prior art misjudges such continuous interference as dynamic tracking error and makes repeated corrections. It effectively eliminates the continuous steering burden generated by the vehicle in maintaining the lane on a constant cross slope road, and improves the stability and driving smoothness of straight driving.

[0034] 3. This application obtains the steering command residual by comparing the actual steering command with the expected steering angle calculated based on the lateral position error and heading angle error, and calculates the off-center steering angle compensation amount accordingly. It can adaptively estimate and compensate for the inherent steering deviation of the vehicle caused by uneven cargo loading, solve the problem of slow drift caused by long-term changes in the vehicle's center of gravity, avoid the response hysteresis and overshoot risk caused by traditional controllers that need to rely on a large integral term to combat such extremely low frequency interference, and enhance the system's adaptability to different load states.

[0035] 4. This application achieves decoupling and coordination of vehicle lateral displacement control and heading attitude control by inputting the lateral position error and heading angle error into a preset dual-channel PID controller, and independently generating the position channel steering amount and heading channel steering amount. This solves the problem that a single control channel is difficult to optimize lateral position convergence and heading angle stability at the same time. The cooperation of the two channels can more effectively suppress the lateral sway of the vehicle and improve the convergence speed of lane centering and the smoothness of the driving trajectory.

[0036] 5. This application generates the final steering angle by linearly superimposing the cross slope steering angle compensation, the off-center load steering angle compensation, and the dual-channel PID output. The algorithm has a clear structure, clear physical meaning of each compensation quantity, and low computational load. It solves the engineering problems of complex advanced control algorithm models, heavy computational burden, and difficulty in real-time operation on vehicle controllers. It provides an efficient solution that is easy to implement, calibrate, and deploy, which is conducive to large-scale application in commercial vehicles. Attached Figure Description

[0037] To more clearly illustrate the technical solution of this application, the accompanying drawings used in the description will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0038] Figure 1 This is a flowchart of a lane keeping assist control method for commercial vehicles that takes into account road cross slope and cargo off-center loading in one embodiment of this application.

[0039] Figure 2 This is a schematic block diagram of a commercial vehicle lane keeping assist control system that takes into account road cross slope and cargo off-center loading in one embodiment of this application.

[0040] Figure 3 This is a schematic diagram of the hardware structure of an electronic device in one embodiment of this application. Detailed Implementation

[0041] To make the purpose, features, and advantages of this application more apparent and understandable, specific embodiments and accompanying drawings will be used to clearly and completely describe the technical solution protected by this application. Obviously, the embodiments described below are only some embodiments of this application, and not all embodiments. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0042] The lane-keeping assist control method for commercial vehicles according to this application will be described in detail below. Specific details such as particular system structures and technologies are set forth for illustrative purposes and not for limitation, in order to provide a thorough understanding of the embodiments of this application. However, those skilled in the art will understand that this application can also be implemented in other embodiments without these specific details.

[0043] In the lane-keeping assist control method for commercial vehicles involved in this application, the term "comprising" indicates the presence of the described feature, integral, step, operation, element, and / or component, but does not exclude the presence or addition of one or more other features, integrals, steps, operations, elements, components, and / or collections thereof. The terms "comprising," "including," "having," and variations thereof all mean "including but not limited to," unless otherwise specifically emphasized.

[0044] To facilitate a clear description of the technical solutions of this application, the terms "first" and "second" are used to distinguish identical or similar items with essentially the same function and effect. Those skilled in the art will understand that the terms "first" and "second" do not limit the quantity or execution order, and that the terms "first" and "second" do not necessarily imply that they are different.

[0045] The terms "one embodiment" or "some embodiments" used in this application mean that one or more embodiments of this application include the specific features, structures, or characteristics described in that embodiment. Therefore, the phrases "in one embodiment," "in some embodiments," "in other embodiments," "in still other embodiments," etc., appearing in different parts of this application do not necessarily refer to the same embodiment, but rather mean "one or more, but not all, embodiments," unless otherwise specifically emphasized.

[0046] The technical solutions in the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings.

[0047] The lane keeping assist control method for commercial vehicles provided in this application is executed by a computer device. Accordingly, the lane keeping assist control system for commercial vehicles that takes into account road cross slope and cargo eccentricity runs in the computer device.

[0048] Figure 1 This is a flowchart of a lane-keeping assist control method for commercial vehicles that considers road cross slope and cargo eccentricity, according to one embodiment of this application. Figure 1 The implementing entity can be a lane-keeping assist control system for commercial vehicles. Depending on different requirements, the order of steps in this flowchart can be changed, and some steps can be omitted.

[0049] like Figure 1 As shown, the lane keeping assist control method for commercial vehicles that takes into account road cross slope and cargo eccentricity includes: Step S1: Real-time acquisition of vehicle operation data, including lateral acceleration, vehicle speed, yaw rate, lateral position error, and heading angle error. The lateral position error represents the lateral offset of the vehicle from the center of the lane, and the heading angle error represents the angle error between the vehicle's heading angle and the lane direction.

[0050] By acquiring five key vehicle state and attitude information—lateral acceleration, vehicle speed, yaw rate, lateral position error, and heading angle error—in real time and synchronously, a comprehensive, real-time, and interconnected data foundation is provided for the entire control system. This enables subsequent algorithms to make comprehensive judgments and calculations based on the vehicle's own kinematic response, its relative position with the lane, and its heading attitude, thereby ensuring the integrity and accuracy of the entire control decision-making basis.

[0051] In some specific embodiments, in step S1, the lateral acceleration is obtained by an inertial measurement unit (IMU) installed on the vehicle; Vehicle speed is obtained through a vehicle speed sensor installed on the vehicle; Yaw rate is obtained through a yaw rate sensor installed on the vehicle; Lateral position error and heading angle error are obtained through a vision system installed on the vehicle.

[0052] By explicitly defining that lateral acceleration is obtained by an inertial measurement unit, vehicle speed by a vehicle speed sensor, yaw rate by a yaw rate sensor, and lateral position error and heading angle error by a vision system, specific, reliable, and mature hardware sources for various key data are specified. This ensures the professionalism and accuracy of the acquired vehicle operation data and provides a high-quality and reliable sensor data foundation for the stable operation of the entire control algorithm.

[0053] In some specific embodiments, the vehicle vision system identifies lane lines, calculates the lateral distance between the vehicle and the center of the lane as the lateral position error, and calculates the angle between the vehicle's heading angle and the lane direction as the heading angle error.

[0054] By providing a complete formulaic process for calculating the net lateral acceleration component, performing low-pass filtering to obtain the equivalent lateral acceleration, and then mapping it to the cross slope steering angle compensation, the entire calculation process from raw sensor data to cross slope compensation is clearly and repeatably implemented. This ensures the consistency and transparency of the algorithms for cross slope interference estimation and compensation, giving the compensation mechanism a clear mathematical basis and engineering-implementable steps.

[0055] Step S2: Calculate the equivalent lateral acceleration caused by the road cross slope based on the lateral acceleration, vehicle speed and yaw rate, and map the equivalent lateral acceleration into the cross slope steering angle compensation amount.

[0056] By calculating and separating the equivalent lateral acceleration caused by the road cross slope based on lateral acceleration, vehicle speed, and yaw rate, and mapping it to the cross slope steering angle compensation, the system can proactively identify and quantify the influence of the external environmental factor of road lateral inclination on the constant or gradually changing lateral force generated by the vehicle. This allows for the introduction of targeted feedforward compensation in advance into the control command, effectively reducing the output pressure and integral accumulation of the feedback controller in order to combat such steady-state disturbances, and improving the straight-line driving stability and control efficiency of the vehicle on cross-slope roads.

[0057] In some specific embodiments, step S2 specifically includes: Calculate the net lateral acceleration component :

[0058] in, Indicates lateral acceleration; Indicates vehicle speed; Indicates yaw rate; For the lateral acceleration component Low-pass filtering is performed to obtain the equivalent lateral acceleration. The formula is:

[0059] This indicates the cutoff frequency of the first low-pass filter. Equivalent lateral acceleration Mapped to cross slope turning angle compensation amount The formula is:

[0060] This represents the mapping coefficient calibrated through experiments.

[0061] By providing a complete formulaic process for calculating the net lateral acceleration component, performing low-pass filtering to obtain the equivalent lateral acceleration, and then mapping it to the cross slope steering angle compensation, the entire calculation process from raw sensor data to cross slope compensation is clearly and repeatably implemented. This ensures the consistency and transparency of the algorithms for cross slope interference estimation and compensation, giving the compensation mechanism a clear mathematical basis and engineering-implementable steps.

[0062] In some specific embodiments, the first low-pass filter cutoff frequency Set as Hz.

[0063] By setting the cutoff frequency of the first low-pass filter used to filter the equivalent lateral acceleration to a range of 0.10 to 0.25 Hz, the high-frequency lateral acceleration components generated by the vehicle's dynamic steering motion and sensor noise can be effectively filtered out, while retaining the low-frequency or quasi-static acceleration components caused by the road cross slope. This ensures the accuracy and stability of the extracted cross slope equivalent acceleration signal and avoids the adverse effects of high-frequency interference on cross slope estimation.

[0064] In some specific embodiments, the mapping coefficients The calibration was obtained through straight-line driving tests on roads with known cross slope angles or known equivalent lateral accelerations. Specifically: Record the constant front wheel steering angle required to maintain the vehicle's straight-line travel within the lane. And it is calculated according to the following formula: .

[0065] By specifying mapping coefficients By conducting straight-line driving calibration experiments on roads with known cross slope angles or known equivalent lateral accelerations, the constant front wheel steering angle required to maintain straight-line driving of the vehicle is recorded, and the coefficient is determined based on its ratio to the equivalent lateral acceleration. This establishes an accurate quantitative relationship between the equivalent lateral acceleration and the actual required steering compensation angle based on real vehicle data, enabling the cross slope compensation amount to truly reflect the physical requirements of the vehicle under specific conditions, thus improving the accuracy and practicality of the compensation.

[0066] In some specific embodiments, when calibrating the mapping coefficients During the process, straight-line driving calibration experiments were conducted on roads with known cross slope angles. Then, the mapping coefficients corresponding to the required cross slope angles were obtained using linear interpolation. .

[0067] By calibrating the mapping coefficients By conducting experiments on roads with several known cross slope angles and using linear interpolation to obtain the coefficients corresponding to the required cross slope angles, an efficient and feasible coefficient calibration strategy is provided. This strategy allows for obtaining a continuous coefficient mapping relationship without exhaustive testing of all possible cross slope angles, reducing the complexity and cost of calibration work, while ensuring the rationality and smooth transition of compensation coefficients under different cross slope conditions.

[0068] Step S3: Calculate the steering command residual caused by cargo eccentricity based on the comparison between the actual steering command and the expected steering angle, and calculate the eccentricity steering angle compensation amount based on the steering command residual. The desired steering angle is calculated based on the lateral position error and the heading angle error.

[0069] By comparing the actual steering command with the expected steering angle calculated based on lateral position error and heading angle error, the steering command residual is obtained, and the off-center steering angle compensation is calculated based on this residual. This can automatically identify the inherent steering deviation caused by the long-term, slow shift of the vehicle's center of gravity due to uneven cargo loading, and realize the estimation and compensation of this extremely low-frequency interference. This avoids the response lag or overshoot problems that may occur in the integral link of traditional feedback control to overcome such deviations, and enhances the system's self-adaptability to different load states.

[0070] In some specific embodiments, step S3 specifically includes: Calculate the steering command residual The formula is:

[0071] in, Indicates the actual turning instruction; This indicates that the desired turning angle is calculated based on the lateral position error and the heading angle error. Steering command residual Low-pass filtering is performed to obtain the off-center steering angle compensation amount. The formula is:

[0072] This indicates the cutoff frequency for the second low-pass filter.

[0073] By providing a specific formula for calculating the steering command residual, which is the difference between the actual steering command and the desired steering angle, and specifying that the residual should be low-pass filtered to obtain the off-center steering angle compensation amount, a calculation method for estimating the impact of cargo off-center loading based on the long-term deviation of the controller output is clarified. This enables the separation of low-frequency components representing slow-varying load disturbances from mixed control signals, providing a clear operational path for achieving adaptive off-center loading compensation.

[0074] In some specific embodiments, the cutoff frequency of the second low-pass filter processing Set as Hz.

[0075] By setting the cutoff frequency of the second low-pass filter used to filter the steering command residual to an extremely low range of 0.01 to 0.025 Hz, it is ensured that all high-frequency dynamic errors and noise can be effectively filtered out, and only the DC or near-DC component of the steering deviation caused by the ultra-slow variable factor of cargo off-center loading is extracted. This accurately captures the steady-state effect caused by long-term load imbalance and avoids misjudging short-term dynamic errors as off-center loading interference.

[0076] In some specific embodiments, the following features are provided: .

[0077] By limiting the cutoff frequency of the second low-pass filter to no more than one-tenth of the cutoff frequency of the first low-pass filter, the bandwidth of the off-center load estimation channel is clearly constrained to be much lower than that of the cross slope estimation channel. This strictly distinguishes between the two types of interference at different time scales—cargo off-center load and road cross slope—from a frequency perspective, effectively preventing coupling and mutual interference between the two types of compensation signals and ensuring the independence and accuracy of their respective estimations and compensations.

[0078] In some specific embodiments, the desired steering angle is... The steering angle is calculated using a pre-defined PID reference model. This model takes lateral position error and heading angle error as inputs to simulate the required steering angle under ideal conditions without road cross slope or cargo eccentricity interference, and uses this as the desired steering angle. Output.

[0079] The desired steering angle is calculated by a pre-set PID reference model. This model takes the lateral position error and heading angle error as inputs and simulates the desired steering response under ideal, undisturbed conditions. It provides a stable, consistent, and ideal reference value for calculating the steering command residual, which is not affected by actual disturbances. This allows the calculated residual to more purely reflect the deviation introduced by non-ideal factors (such as off-center load) in the actual system, thus improving the accuracy of off-center load estimation.

[0080] Step S4: Input the lateral position error and heading angle error into the preset dual-channel PID controller, and output the position channel steering amount and heading channel steering amount.

[0081] By inputting the lateral position error and heading angle error into a preset dual-channel PID controller, the position channel steering amount and heading channel steering amount are generated in parallel. This decouples the two closely related but differently focused sub-problems of vehicle lateral displacement tracking control and heading angle stability control. This allows the controller to simultaneously and independently optimize the lateral convergence speed and suppress heading sway, thereby achieving a more coordinated and stable lane centering control effect.

[0082] In some specific embodiments, in step S4, the dual-channel PID controller includes a position channel and a heading channel: The position channel takes the lateral position error as input and outputs the position channel steering amount. The heading channel takes the heading angle error as input and outputs the heading channel turning amount.

[0083] By specifically defining the dual-channel PID controller as including a position channel with lateral position error as input and a heading channel with heading angle error as input, the specific division of labor and the correspondence of input signals of the dual-channel control architecture are clarified. This makes the controller structure clear and its functions well-defined, facilitating independent parameter tuning and performance analysis. Thus, it provides a structural guarantee for achieving the dual goals of accurate position tracking and stable heading control.

[0084] In some specific embodiments, the proportional gain Kp, integral gain Ki, and derivative gain Kd of the PID controller in the position channel and heading channel are adjusted according to the vehicle speed and load status, and the adjustment rules are as follows: The higher the vehicle speed, the lower the proportional gain Kp, the lower the integral gain Ki, and the higher the derivative gain Kd. The fuller the vehicle load, the higher the proportional gain Kp, the higher the integral gain Ki, and the higher the derivative gain Kd.

[0085] By specifying the proportional, integral, and derivative gains of the PID controller in the position and heading channels, and adjusting them according to the vehicle speed and load status, the system provides adjustment rules that reduce the proportional and integral gains and increase the derivative gains as the vehicle speed increases, and increase all gains as the load increases. This allows the controller parameters to adapt to changes in the vehicle's dynamic characteristics, maintain appropriate control rigidity and damping under different operating conditions, and optimize the system's transient response and steady-state performance.

[0086] Step S5: Linearly superimpose the cross slope steering angle compensation, off-center load steering angle compensation, position channel steering, and heading channel steering to output the final steering angle.

[0087] By linearly superimposing the cross slope steering angle compensation, off-center steering angle compensation, position channel steering, and heading channel steering from different control modules, the final steering angle command is generated in a fusion manner. This achieves multi-strategy synergy between feedforward compensation and feedback control, static disturbance suppression and dynamic error correction, enabling the control system to comprehensively utilize control quantities from different sources to cope with complex operating conditions, thereby optimizing the overall response performance of the system and improving the comprehensive control efficiency.

[0088] In some specific embodiments, the formula for linear superposition in step S5 is:

[0089] in, Indicates the final steering angle; Indicates the position channel turning amount; Indicates the turning point of the heading channel; Indicates the amount of cross slope turning angle compensation; This indicates the amount of compensation for the off-center load steering angle; This indicates the preset heading channel weighting coefficient; This indicates the preset position channel weighting coefficient; This indicates the preset cross slope turning angle weighting coefficient; This indicates the preset weighting coefficient for the off-center load steering angle.

[0090] By providing a specific formula for the final steering angle, which is a linear superposition of four parts: the position channel steering amount, the heading channel steering amount, the cross slope steering angle compensation amount, and the off-center steering angle compensation amount, and introducing their respective preset weight coefficients, the mathematical expression of multi-control quantity fusion is clarified, making the synthesis process adjustable and transparent. It allows the priority between different control objectives to be balanced by adjusting the weights, so as to achieve the optimization of overall performance.

[0091] In some specific embodiments, the weighting coefficient , , , The following calibration method was used to determine the optimal control performance: Real-vehicle tests were conducted under different road cross slopes, uneven cargo loading, and vehicle speeds. The optimization objectives were lateral deviation accuracy and driving stability while maintaining lane position. The weighting coefficients were repeatedly adjusted until the optimal control effect was obtained, and the corresponding optimal weighting coefficients were used as the basis for determination. , , , The calibration value.

[0092] By specifying that each weight coefficient is determined through real-vehicle testing under different operating conditions and repeatedly adjusted with lateral offset accuracy and driving stability as optimization objectives, it is ensured that the weight coefficients are the result of actual verification and performance optimization. This allows the final linear superposition to most effectively integrate the outputs of each control module, thereby achieving the optimal lane keeping control effect in real complex road environments.

[0093] Step S6: Generate a steering command based on the final steering angle and send it to the vehicle's steering actuator for execution.

[0094] By generating specific steering commands based on the final calculated comprehensive steering angle and sending them to the vehicle's steering actuator to drive its action, a complete control closed loop from state perception and decision calculation to physical execution is completed. This ensures that the ideal control quantities calculated by all algorithms can be accurately and timely converted into the actual steering behavior of the vehicle, thereby ultimately realizing and verifying the effectiveness and real-time performance of the lane keeping assist function.

[0095] In some specific embodiments, in step S6, the steering command must meet safety restrictions, including steering gear angle limits and steering gear angle change rate limits.

[0096] By requiring the generated steering commands to meet safety restrictions, including steering gear angle limits and angle change rate limits, necessary safety boundary constraints are added to the output of the control system. This prevents excessively large or rapidly changing steering commands due to algorithm calculation anomalies or extreme operating conditions, ensuring the safety and smoothness of vehicle steering execution at the command level and avoiding potentially dangerous maneuvers.

[0097] In some specific embodiments, the security restrictions specifically include: When the vehicle speed is between 0 and 20 km / h, the steering gear angle limit is ±500°, and the steering gear angle change rate limit is 180° / s. That is, it is mandatory that the steering gear angle is [-500°, 500°] and the steering gear angle change rate is not higher than 180° / s. When the vehicle speed is between 20 and 40 km / h, the steering gear angle limit is ±400°, and the steering gear angle change rate limit is 150° / s. That is, it is mandatory that the steering gear angle is [-400°, 400°] and the steering gear angle change rate is not higher than 150° / s. When the vehicle speed is between 40 and 60 km / h, the steering gear angle limit is ±400°, and the steering gear angle change rate limit is 100° / s. That is, it is mandatory that the steering gear angle is [-400°, 400°] and the steering gear angle change rate is not higher than 100° / s. When the vehicle speed is in the range of 60 to 80 km / h, the steering gear angle limit is ±300°, and the steering gear angle change rate limit is 80° / s. That is, it is mandatory that the steering gear angle is [-300°, 300°] and the steering gear angle change rate is not higher than 80° / s. When the vehicle speed is between 80 and 100 km / h, the steering gear angle limit is ±100°, and the steering gear angle change rate limit is 50° / s. That is, it is mandatory that the steering gear angle is [-100°, 100°] and the steering gear angle change rate is not higher than 50° / s.

[0098] By providing detailed values ​​for steering gear angle limits and angle change rate limits at different vehicle speed segments—for example, allowing larger angles and faster rates at low speeds while imposing stricter restrictions at high speeds—this provides a step-by-step implementation standard for safety constraints that are dynamically related to vehicle speed. This allows safety restriction strategies to align with the vehicle's stability and handling requirements at different speeds, thereby ensuring driving safety across the entire speed range more scientifically and effectively.

[0099] The following are embodiments of a commercial vehicle lane keeping assist control system that takes into account road cross slope and cargo eccentricity provided in this application. This commercial vehicle lane keeping assist control system that takes into account road cross slope and cargo eccentricity belongs to the same inventive concept as the commercial vehicle lane keeping assist control methods in the above embodiments. For details not described in detail in the embodiments of the commercial vehicle lane keeping assist control system, please refer to the embodiments of the commercial vehicle lane keeping assist control methods that take into account road cross slope and cargo eccentricity.

[0100] like Figure 2As shown, a commercial vehicle lane keeping assist control system that considers road cross slope and cargo eccentricity includes: The data acquisition module is used to acquire vehicle operation data in real time, including lateral acceleration, vehicle speed, yaw rate, lateral position error and heading angle error. The lateral position error represents the lateral offset of the vehicle from the center of the lane, and the heading angle error represents the angle error between the vehicle's heading angle and the lane direction. The cross slope compensation calculation module is used to calculate the equivalent lateral acceleration caused by the road cross slope based on lateral acceleration, vehicle speed and yaw rate, and map the equivalent lateral acceleration into cross slope steering angle compensation. The off-center load compensation calculation module is used to calculate the steering command residual caused by the off-center load based on the comparison between the actual steering command and the expected steering angle, and to calculate the off-center load steering angle compensation based on the steering command residual; wherein, the expected steering angle is calculated based on the lateral position error and the heading angle error; The dual-channel PID module is used to input the lateral position error and heading angle error into the preset dual-channel PID controller, and output the position channel steering amount and heading channel steering amount. The steering angle generation module is used to linearly superimpose the cross slope steering angle compensation, off-center load steering angle compensation, position channel steering, and heading channel steering to output the final steering angle. The special instruction generation and execution module is used to generate steering instructions based on the final steering angle and send them to the vehicle's steering actuator for execution.

[0101] The commercial vehicle lane keeping assist control system of this embodiment is used to implement a commercial vehicle lane keeping assist control method that takes into account road cross slope and cargo off-center loading.

[0102] This application also provides an electronic device for implementing the various embodiments of this application. Figure 3 To illustrate the hardware structure of an electronic device according to various embodiments of this application, as shown in the following diagram... Figure 3 As shown, the electronic device includes a memory, a processor, and a computer program stored in the memory and capable of running on the processor.

[0103] Those skilled in the art will understand that the electronic device structure involved in the embodiments of this application does not constitute a limitation on the electronic device. The electronic device may include more or fewer components than shown in the figure, or combine certain components, or have different component arrangements.

[0104] In embodiments of this application, electronic devices include, but are not limited to, laptop computers, desktop computers, workstations, personal digital assistants, servers, blade servers, mainframe computers, and other suitable computers. Electronic devices may also represent various forms of mobile devices and other similar computing devices. The components shown herein, their connections and relationships, and their functions are merely examples and are not intended to limit the implementation of the embodiments of this application described and / or claimed herein.

[0105] In this application embodiment, the processor can be implemented using at least one of an Application-Specific Integrated Circuit (ASIC), a Digital Signal Processor (DSP), a Digital Signal Processing Device (DSPD), a processor, a controller, a microcontroller, a microprocessor, or an electronic unit designed to perform the functions described herein. In some cases, such implementations can be implemented within a controller. For software implementations, implementations such as processes or functions can be implemented with separate software modules that allow the performance of at least one function or operation. The software code can be implemented by a software application (or program) written in any suitable programming language, and the software code can be stored in memory and executed by the controller.

[0106] In addition, the electronic device includes some functional modules not shown, which will not be described in detail here.

[0107] Those skilled in the art will understand that the various aspects of the electronic device provided in this application can be implemented as a system, method, or program product. Therefore, the various aspects of this application can be specifically implemented in the following forms: a completely hardware implementation, a completely software implementation (including firmware, microcode, etc.), or a combination of hardware and software aspects, collectively referred to herein as a "circuit," "module," or "system."

[0108] This application also provides a storage medium storing a program product capable of implementing a lane-keeping assist control method for commercial vehicles that takes into account road cross slope and cargo eccentricity. In some possible implementations, various aspects of this application may also be implemented as a program product comprising program code that, when run on a terminal device, causes the terminal device to perform the steps described in the "Exemplary Methods" section of this specification according to the various exemplary embodiments of this application.

[0109] The storage medium may be any combination of one or more readable media. A readable medium may be a readable signal medium or a readable storage medium. A readable storage medium may be, for example,, but not limited to, an electrical, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any combination thereof. More specific examples (a non-exhaustive list) of readable storage media include: electrical connections having one or more wires, portable disks, hard disks, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), optical fiber, portable compact disk read-only memory (CD-ROM), optical storage devices, magnetic storage devices, or any suitable combination thereof.

[0110] The above description of the disclosed embodiments enables those skilled in the art to make or use this application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of this application. Therefore, this application is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A lane-keeping assist control method for commercial vehicles that considers road cross slope and cargo eccentricity, characterized in that, include: S1. Real-time acquisition of vehicle operation data, including lateral acceleration, vehicle speed, yaw rate, lateral position error and heading angle error, where the lateral position error represents the lateral offset of the vehicle from the center of the lane, and the heading angle error represents the angle error between the vehicle's heading angle and the lane direction; S2. Calculate the equivalent lateral acceleration caused by the road cross slope based on lateral acceleration, vehicle speed and yaw rate, and map the equivalent lateral acceleration to the cross slope steering angle compensation amount; S3. Calculate the steering command residual caused by cargo eccentricity based on the comparison between the actual steering command and the expected steering angle, and calculate the eccentricity steering angle compensation amount based on the steering command residual; The desired steering angle is calculated based on the lateral position error and the heading angle error. S4. Input the lateral position error and heading angle error into the preset dual-channel PID controller, and output the position channel steering amount and heading channel steering amount; S5. Linearly superimpose the cross slope steering angle compensation, eccentric load steering angle compensation, position channel steering angle, and heading channel steering angle to output the final steering angle; S6. Generate steering commands based on the final steering angle and send them to the vehicle's steering actuator for execution.

2. The commercial vehicle lane keeping assist control method as described in claim 1, characterized in that, Step S2 specifically includes: Calculate the net lateral acceleration component : in, Indicates lateral acceleration; Indicates vehicle speed; Indicates yaw rate; For the lateral acceleration component Low-pass filtering is performed to obtain the equivalent lateral acceleration. The formula is: This indicates the cutoff frequency of the first low-pass filter. Equivalent lateral acceleration Mapped to cross slope turning angle compensation amount The formula is: This represents the mapping coefficient calibrated through experiments.

3. The commercial vehicle lane keeping assist control method as described in claim 2, characterized in that, First low-pass filter cutoff frequency Set as Hz.

4. The commercial vehicle lane keeping assist control method as described in claim 1, characterized in that, Step S3 specifically includes: Calculate the steering command residual The formula is: in, Indicates the actual turning instruction; This indicates that the desired turning angle is calculated based on the lateral position error and the heading angle error. Steering command residual Low-pass filtering is performed to obtain the off-center steering angle compensation amount. The formula is: This indicates the cutoff frequency for the second low-pass filter.

5. The commercial vehicle lane keeping assist control method as described in claim 4, characterized in that, Desired steering angle The steering angle is calculated using a pre-defined PID reference model. This model takes lateral position error and heading angle error as inputs to simulate the required steering angle under ideal conditions without road cross slope or cargo eccentricity interference, and uses this as the desired steering angle. Output.

6. The commercial vehicle lane keeping assist control method as described in claim 1, characterized in that, In the position and heading channels, the proportional gain Kp, integral gain Ki, and derivative gain Kd of the PID controller are adjusted according to the vehicle speed and load status, and the adjustment rules are as follows: The higher the vehicle speed, the lower the proportional gain Kp, the lower the integral gain Ki, and the higher the derivative gain Kd. The fuller the vehicle load, the higher the proportional gain Kp, the higher the integral gain Ki, and the higher the derivative gain Kd.

7. A lane keeping assist control system for commercial vehicles that takes into account road cross slope and cargo eccentricity, characterized in that, A method for implementing the lane keeping assist control method for commercial vehicles as described in any one of claims 1-6, comprising: The data acquisition module is used to acquire vehicle operation data in real time, including lateral acceleration, vehicle speed, yaw rate, lateral position error and heading angle error. The lateral position error represents the lateral offset of the vehicle from the center of the lane, and the heading angle error represents the angle error between the vehicle's heading angle and the lane direction. The cross slope compensation calculation module is used to calculate the equivalent lateral acceleration caused by the road cross slope based on lateral acceleration, vehicle speed and yaw rate, and map the equivalent lateral acceleration into cross slope steering angle compensation. The off-center load compensation calculation module is used to calculate the steering command residual caused by the off-center load based on the comparison between the actual steering command and the expected steering angle, and to calculate the off-center load steering angle compensation based on the steering command residual; wherein, the expected steering angle is calculated based on the lateral position error and the heading angle error; The dual-channel PID module is used to input the lateral position error and heading angle error into the preset dual-channel PID controller, and output the position channel steering amount and heading channel steering amount. The steering angle generation module is used to linearly superimpose the cross slope steering angle compensation, off-center load steering angle compensation, position channel steering, and heading channel steering to output the final steering angle. The special instruction generation and execution module is used to generate steering instructions based on the final steering angle and send them to the vehicle's steering actuator for execution.

8. An electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that, When the processor executes a computer program, it implements the steps of the commercial vehicle lane keeping assist control method as described in any one of claims 1-6.

9. A storage medium storing a computer program, characterized in that, When the computer program is executed by a processor, it implements the steps of the commercial vehicle lane keeping assist control method as described in any one of claims 1-6.

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