A four-wheel steering system testing method and system based on load simulation

Abstract

The application discloses a kind of four-wheel steering system test method and system based on load simulation, according to the preset real vehicle installation mode, the four-wheel steering system to be tested is installed and fixed;According to the preset load simulation condition, the four-wheel steering system is applied to preset load;According to the preset target corner instruction control four-wheel steering system response, and real-time acquisition four-wheel steering system real-time running parameter;The real-time running parameter is compared with preset running parameter, to judge whether four-wheel steering system is qualified.In different load conditions, the comprehensive test is carried out to the corner response precision, running stability and working reliability of four-wheel steering system.The present application can effectively overcome the problems existing in the prior art test method, such as single working condition simulation, insufficient test precision, poor result reliability, etc., so as to realize the accurate test and comprehensive evaluation of four-wheel steering system under various complex conditions.

Description

Technical Field

[0001] This invention relates to the field of automotive steering system testing technology, specifically a four-wheel steering system testing method and system based on load simulation. Background Technology

[0002] With the rapid development of the automotive industry, four-wheel steering systems, due to their ability to significantly improve vehicle handling stability and driving safety, have become an important technological direction in high-end models and intelligent driving fields. This system, by precisely controlling the steering angles of the front and rear wheels, can effectively reduce the turning radius and improve maneuverability at low speeds; and enhance vehicle stability and reduce the risk of rollover at high speeds. However, the actual performance of four-wheel steering systems is affected by a combination of factors such as road load, driving speed, and steering angle, making its testing far more challenging than that of traditional two-wheel steering systems.

[0003] Currently, testing of four-wheel steering systems primarily relies on real-vehicle road tests or fixed-load bench tests. While these two methods can reflect the system's basic performance to some extent, they generally suffer from significant drawbacks such as long testing cycles, high costs, and limited simulation capabilities. In particular, real-vehicle tests struggle to precisely control key variables like road loads, making it impossible to comprehensively evaluate the system's performance under extreme or complex driving conditions. Although some laboratory testing equipment can simulate certain load conditions, it still suffers from low load simulation accuracy and slow response speed, leading to significant discrepancies between test results and actual driving conditions. Therefore, there is an urgent need to develop a testing method and its supporting system that can accurately simulate complex real-world driving environments and comprehensively evaluate the overall performance of four-wheel steering systems. This has significant engineering application value and practical industrial implications. Summary of the Invention This invention aims to at least solve one of the technical problems existing in the prior art. To this end, this invention provides a test method and system for four-wheel steering systems based on load simulation, which comprehensively tests the steering angle response accuracy, operational stability, and operational reliability of four-wheel steering systems under different load conditions. This invention effectively overcomes the problems of single-condition simulation, insufficient test accuracy, and poor result reliability in existing test methods, thereby achieving accurate testing and comprehensive evaluation of four-wheel steering systems under various complex operating conditions.

[0004] According to a first aspect of the present invention, a test method for a four-wheel steering system based on load simulation includes: The four-wheel steering system to be tested was installed and fixed according to the preset actual vehicle installation method; A preset load is applied to the four-wheel steering system according to the preset load simulation conditions; The four-wheel steering system is controlled to respond according to the preset target steering angle command, and the real-time operating parameters of the four-wheel steering system are collected in real time. The real-time operating parameters are compared with the preset operating parameters to determine whether the four-wheel steering system is qualified.

[0005] According to some embodiments of the present invention, the real-time operating parameters include real-time final steering angle, real-time response time, real-time steering torque, and real-time steering angle fluctuation amplitude; The step of comparing the real-time operating parameters with preset operating parameters to determine whether the four-wheel steering system is qualified includes: If the difference between the real-time final steering angle and the preset target steering angle is less than a first preset threshold, the response time is less than a second preset threshold, the difference between the real-time steering torque and the preset steering torque is less than a third preset threshold, and the real-time steering angle fluctuation amplitude is less than a fourth preset threshold, then the four-wheel steering system is deemed qualified; otherwise, it is deemed unqualified.

[0006] According to some embodiments of the present invention, applying a preset load to the four-wheel steering system according to a preset load simulation condition includes: The load parameters are dynamically adjusted according to a preset working condition curve. The load parameters include load force, driving speed range, steering angle range, and steering frequency.

[0007] According to some embodiments of the present invention, applying a preset load to the four-wheel steering system according to a preset load simulation condition further includes: The four-wheel steering system is controlled to be tested under low-speed conditions to verify its steering accuracy and response speed. The vehicle speed under low-speed conditions is controlled within the range of a first preset vehicle speed and a second preset vehicle speed. The four-wheel steering system is controlled to be tested under medium-speed conditions to verify its steering stability. The medium-speed conditions are when the vehicle speed is controlled within the range of a second preset vehicle speed and a third preset vehicle speed. The four-wheel steering system is controlled to be tested under high-speed conditions to verify its steering return performance. The high-speed conditions are defined as controlling the vehicle speed to be within the range of a third preset speed and a fourth preset speed.

[0008] According to some embodiments of the present invention, applying a preset load to the four-wheel steering system according to a preset load simulation condition further includes: The four-wheel steering system is controlled to perform continuous tests for a preset duration in the low-speed, medium-speed, and high-speed operating conditions, respectively.

[0009] According to some embodiments of the present invention, it further includes: An alarm signal is triggered when the load parameters exceed the first preset warning threshold or the real-time operating parameters exceed the second preset warning threshold.

[0010] According to some embodiments of the present invention, the step of installing and fixing the four-wheel steering system to be tested according to a preset actual vehicle installation method further includes: An angle sensor, torque sensor, speed sensor, and pressure sensor are installed at predetermined positions in the four-wheel steering system.

[0011] According to some embodiments of the present invention, the angle sensor is mounted on the front and rear wheel steering axles, and its measurement accuracy is no greater than 0.1°; the torque sensor is disposed on the steering tie rod and the drive motor, and its measurement range is 0 to 500 Nm; the speed sensor has a response time of no greater than 10 ms; and the pressure sensor is mounted on the output end of the load simulation unit.

[0012] According to a second aspect of the present invention, a four-wheel steering system test system based on load simulation includes: The bench test unit is used to install and fix the four-wheel steering system to be tested according to the preset actual vehicle installation method; The load simulation unit is used to apply a preset load to the four-wheel steering system according to a preset load simulation working condition; The four-wheel steering control unit is used to control the response of the four-wheel steering system according to the preset target steering angle command, and to collect the real-time operating parameters of the four-wheel steering system in real time; The data analysis unit is used to compare the real-time operating parameters with preset operating parameters to determine whether the four-wheel steering system is qualified.

[0013] According to some embodiments of the present invention, it further includes: a safety protection unit, which is used to trigger an alarm signal when the load parameter exceeds a first preset warning threshold or the real-time operating parameter exceeds a second preset warning threshold.

[0014] The four-wheel steering system testing method and system according to embodiments of the present invention have at least the following beneficial effects: By installing and fixing the system under test according to a preset vehicle mounting method, the test boundary conditions are ensured to be consistent with the actual vehicle, improving the engineering reliability of the test results. Applying preset loads to simulate working conditions allows for the reproduction of various real road surfaces and driving states in a laboratory environment, solving the problem of traditional test conditions being too singular and unable to cover complex scenarios. Furthermore, controlling the system response according to preset target steering angle commands and collecting operating parameters in real time achieves precise excitation and synchronous monitoring of the system's dynamic behavior, avoiding errors from manual measurement. Finally, by comparing real-time operating parameters with preset operating parameters to determine whether the system is qualified, a quantitative, repeatable, and automated performance evaluation standard is provided for four-wheel steering systems, effectively overcoming the limitations of subjective judgment or single-index evaluation in existing technologies. In summary, this method significantly improves the accuracy, comprehensiveness, and efficiency of four-wheel steering system testing.

[0015] Other features and advantages of the invention will be set forth in the description which follows, and will be apparent in part from the description, or may be learned by practicing the invention. Attached Figure Description

[0016] The present invention will be further described below with reference to the accompanying drawings and embodiments, wherein: Figure 1 This is a flowchart of the four-wheel steering system testing method based on load simulation according to the present invention; Figure 2 This is a flowchart of step S200 of the present invention; Figure 3 This invention relates to a four-wheel steering system test system based on load simulation. Detailed Implementation

[0017] Embodiments of the present invention are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and should not be construed as limiting the present invention.

[0018] In the description of this invention, it should be understood that the orientation descriptions, such as up, down, etc., are based on the orientation or positional relationship shown in the drawings and are only for the convenience of describing this invention and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this invention.

[0019] In the description of this invention, "multiple" refers to two or more. The use of "first" and "second" is for distinguishing technical features only and should not be construed as indicating or implying relative importance, or implicitly indicating the number of indicated technical features or their sequential relationship.

[0020] In the description of this invention, unless otherwise explicitly defined, terms such as "setting," "installing," and "connecting" should be interpreted broadly, and those skilled in the art can reasonably determine the specific meaning of the above terms in this invention in conjunction with the specific content of the technical solution.

[0021] The technical solution of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the embodiments described below are some embodiments of the present invention, not all embodiments.

[0022] Traditional four-wheel steering system testing often relies on real-world road testing or fixed-load test benches, which suffers from problems such as long testing cycles, high costs, limited testing conditions, and low accuracy, making it difficult to comprehensively evaluate system performance under complex operating conditions. Therefore, this invention provides a four-wheel steering system testing method and system based on load simulation, which comprehensively tests the steering angle response accuracy, operational stability, and operational reliability of the four-wheel steering system under different load conditions. This invention effectively overcomes the problems of limited testing condition simulation, insufficient testing accuracy, and poor result reliability in existing testing methods, thereby achieving accurate testing and comprehensive evaluation of four-wheel steering systems under various complex operating conditions.

[0023] Among them, such as Figure 3 As shown, the four-wheel steering system test system includes: a bench test unit, a load simulation unit, a four-wheel steering control unit, and a data analysis unit.

[0024] The load simulation unit includes an adjustable electronically controlled front wheel loading device and a hydraulic rear wheel loading device, an inertial simulation unit and a load parameter control system. It can simulate the axle load changes, road reaction force and inertial torque of the vehicle under different road conditions (such as off-road, high-speed and congestion), with a loading accuracy of ±1%.

[0025] The bench test unit consists of a self-made test device equipped with standard test equipment. It can be adapted to the installation requirements of four-wheel steering systems of different vehicle models, and can fix the four-wheel steering system in the specified position. It can quickly complete the fixation and positioning of the steering system under test, ensuring stability during the test process.

[0026] The four-wheel steering control unit integrates a steering angle sensor, a motor drive module, and a control algorithm module. It can receive test commands and drive the four-wheel steering system, while simultaneously collecting real-time data on the steering angle, speed, and torque of each wheel.

[0027] The data analysis unit is equipped with a high-precision data acquisition card, signal processing software, and operating condition database, which can simultaneously acquire load simulation parameters and steering system response data.

[0028] like Figure 1 As shown, an embodiment of the present invention provides a four-wheel steering system testing method based on load simulation, including but not limited to the following steps: Step S100: Install and fix the four-wheel steering system to be tested according to the preset actual vehicle installation method.

[0029] The four-wheel steering system under test was mounted on the designated position of the bench test unit using a fixing fixture, ensuring that all connections were secure and reliable. Simultaneously, the load simulation module and the four-wheel steering control module were calibrated and connected to various data acquisition sensors, including angle sensors, torque sensors, speed sensors, and pressure sensors. Specifically, angle sensors were mounted on the front and rear steering axles to accurately acquire steering angle data, with a measurement accuracy of no less than 0.1°; torque sensors were installed on the steering tie rods and drive motor to detect torque changes during steering in real time, with a measurement range covering 0–500 Nm; speed sensors were used to acquire wheel speed and steering motor speed data, with a response time of no more than 10 ms; and pressure sensors were installed at the output of the load simulation unit to monitor the magnitude and changes of load force in real time.

[0030] In addition, the bench test unit is connected to the system to complete sensor calibration and data acquisition channel configuration, and communication connections and functional debugging between modules are completed to ensure that the test system is in normal working condition.

[0031] Step S200: Apply a preset load to the four-wheel steering system according to the preset load simulation conditions.

[0032] In this embodiment of the invention, load parameters are dynamically adjusted according to a preset working condition curve. These load parameters include load force, driving speed range, steering angle range, and steering frequency. The load force is determined based on the road surface load type, which includes dry roads, wet roads, and icy / snowy roads.

[0033] Specifically, such as Figure 2 As shown, step S200 includes the following sub-steps: Step S210: Control the four-wheel steering system to test under low-speed conditions to verify its steering accuracy and response speed. Under low-speed conditions, control the vehicle speed to be within the range of the first preset vehicle speed and the second preset vehicle speed.

[0034] In this embodiment, the vehicle speed range for low-speed operation is set to 0–20 km / h.

[0035] Step S220: Control the four-wheel steering system to test under medium speed conditions to verify its steering stability. Medium speed conditions are when the vehicle speed is controlled within the range of the second preset speed and the third preset speed.

[0036] In this embodiment, the vehicle speed range for medium-speed operation is set to 20–60 km / h.

[0037] Step S230: Control the four-wheel steering system to test under high-speed conditions to verify its steering return performance. The high-speed condition is to control the vehicle speed to be within the range of the third preset speed and the fourth preset speed.

[0038] In this embodiment, the vehicle speed range for high-speed operation is set to 60–100 km / h.

[0039] The load simulation unit and the four-wheel steering control unit send load simulation commands to the bench test unit. The bench test unit outputs the corresponding load force according to the command, thereby simulating real road conditions.

[0040] Step S300: Control the four-wheel steering system response according to the preset target steering angle command, and collect the real-time operating parameters of the four-wheel steering system in real time.

[0041] The real-time operating parameters include the real-time final steering angle, real-time response time, real-time steering torque, and real-time steering angle fluctuation range. After inputting the target steering angle command, the four-wheel steering system responds, collecting operating parameters such as steering angle, torque, speed, and load force in real time, and storing and preprocessing the collected data. Simultaneously, the four-wheel steering system is controlled to perform continuous tests for preset durations under low-speed, medium-speed, and high-speed conditions. In this embodiment, at least three sets of tests under different load conditions are completed, with each test lasting no less than 10 minutes.

[0042] Step S400: Compare the real-time operating parameters with the preset operating parameters to determine whether the four-wheel steering system is qualified.

[0043] Specifically, the four-wheel steering system is deemed qualified when the difference between the real-time final steering angle and the preset target steering angle is less than the first preset threshold, the response time is less than the second preset threshold, the difference between the real-time steering torque and the preset steering torque is less than the third preset threshold, and the real-time steering angle fluctuation amplitude is less than the fourth preset threshold; otherwise, it is deemed unqualified.

[0044] like Figure 1 As shown, the four-wheel steering system testing method of this invention further includes the following steps: Step S500: When the load parameters exceed the first preset warning threshold or the real-time operating parameters exceed the second preset warning threshold, an alarm signal is triggered.

[0045] To achieve this function, the four-wheel steering system testing system of this embodiment of the invention also includes a safety protection unit for executing the above-mentioned alarm and corresponding safety protection measures.

[0046] Taking the four-wheel steering system test of a certain type of off-road vehicle as an example: The load parameters are set as follows: front axle load 2000-3000kg, rear axle load 2500-3500kg, to simulate axle load changes under off-road conditions; The input target rotation angle is 30°, and the actual rotation angle after the system response is 29.8°, with a rotation angle error rate of 0.67% and a response delay time of 0.12s, which meets the test standards. When the load suddenly increased to 4000kg, the system automatically triggered an overload warning. After investigation, it was found that the pressure of the hydraulic loading device was abnormal. After adjustment and retesting, the data returned to normal.

[0047] The embodiments of the present invention have at least the following beneficial effects: 1. Comprehensive working condition simulation: Through the collaborative work of the load simulation unit, the four-wheel steering control unit and the bench test unit, it can accurately simulate a variety of complex road conditions, including different adhesion coefficients such as dry road, wet road, and icy and snowy road, as well as different driving speed ranges such as low speed (0-20 km / h), medium speed (20-60 km / h) and high speed (60-100 km / h). It also supports dynamic adjustment of different steering angles and steering frequencies, thereby realizing the performance testing of the four-wheel steering system under all working conditions.

[0048] 2. High Testing Accuracy: The data analysis unit employs high-precision sensors (angle measurement accuracy ≤0.1°, torque measurement range 0~500 Nm, speed sensor response time ≤10 ms) and high-speed data acquisition technology. Combined with the ±1% loading accuracy of the load simulation unit, this ensures the accuracy and reliability of the acquired operating parameters. Furthermore, by comparing the measured data with preset operating parameters using multiple thresholds, the accuracy and consistency of the test results are further improved, effectively reducing test errors.

[0049] 3. High Testing Efficiency: No extensive real-vehicle road testing is required; a comprehensive evaluation of the four-wheel steering system can be completed through laboratory simulation testing. Employing an automated, repetitive testing process with at least three sets of different load conditions, each lasting no less than 10 minutes, significantly shortens the testing cycle and reduces manpower and material costs. Furthermore, the system supports flexible addition or replacement of components such as sensors and load simulation units according to testing needs, facilitating functional expansion and upgrades, and adapting to the requirements of different vehicle models and testing scenarios.

[0050] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "illustrative embodiment," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0051] The embodiments of the present invention have been described in detail above with reference to the accompanying drawings. However, the present invention is not limited to the above embodiments. Within the scope of knowledge possessed by those skilled in the art, various changes can be made without departing from the spirit of the present invention.

Claims

1. A test method for a four-wheel steering system based on load simulation, characterized in that, include: The four-wheel steering system to be tested was installed and fixed according to the preset actual vehicle installation method; A preset load is applied to the four-wheel steering system according to the preset load simulation conditions; The four-wheel steering system is controlled to respond according to the preset target steering angle command, and the real-time operating parameters of the four-wheel steering system are collected in real time. The real-time operating parameters are compared with the preset operating parameters to determine whether the four-wheel steering system is qualified.

2. The four-wheel steering system testing method according to claim 1, characterized in that, The real-time operating parameters include real-time final steering angle, real-time response time, real-time steering torque, and real-time steering angle fluctuation amplitude. The step of comparing the real-time operating parameters with preset operating parameters to determine whether the four-wheel steering system is qualified includes: If the difference between the real-time final steering angle and the preset target steering angle is less than a first preset threshold, the response time is less than a second preset threshold, the difference between the real-time steering torque and the preset steering torque is less than a third preset threshold, and the real-time steering angle fluctuation amplitude is less than a fourth preset threshold, then the four-wheel steering system is deemed qualified; otherwise, it is deemed unqualified.

3. The four-wheel steering system test method according to claim 2, characterized in that, Applying a preset load to the four-wheel steering system according to a preset load simulation condition includes: The load parameters are dynamically adjusted according to a preset working condition curve. The load parameters include load force, driving speed range, steering angle range, and steering frequency.

4. The four-wheel steering system test method according to claim 3, characterized in that, Applying a preset load to the four-wheel steering system according to a preset load simulation condition further includes: The four-wheel steering system is controlled to be tested under low-speed conditions to verify its steering accuracy and response speed. The vehicle speed under low-speed conditions is controlled within the range of a first preset vehicle speed and a second preset vehicle speed. The four-wheel steering system is controlled to be tested under medium-speed conditions to verify its steering stability. The medium-speed conditions are when the vehicle speed is controlled within the range of a second preset vehicle speed and a third preset vehicle speed. The four-wheel steering system is controlled to be tested under high-speed conditions to verify its steering return performance. The high-speed conditions are defined as controlling the vehicle speed to be within the range of a third preset speed and a fourth preset speed.

5. The four-wheel steering system test method according to claim 4, characterized in that, Applying a preset load to the four-wheel steering system according to a preset load simulation condition further includes: The four-wheel steering system is controlled to perform continuous tests for a preset duration in the low-speed, medium-speed, and high-speed operating conditions, respectively.

6. The four-wheel steering system test method according to claim 3, characterized in that, Also includes: An alarm signal is triggered when the load parameters exceed the first preset warning threshold or the real-time operating parameters exceed the second preset warning threshold.

7. The four-wheel steering system test method according to claim 3, characterized in that, The installation and fixation of the four-wheel steering system to be tested according to the preset actual vehicle installation method also includes: An angle sensor, torque sensor, speed sensor, and pressure sensor are installed at predetermined positions in the four-wheel steering system.

8. The four-wheel steering system testing method according to claim 7, characterized in that, The angle sensor is mounted on the front and rear wheel steering axles, and its measurement accuracy is no greater than 0.1°; the torque sensor is set on the steering tie rod and the drive motor, and its measurement range is 0 to 500 Nm; the speed sensor has a response time of no more than 10 ms; and the pressure sensor is mounted on the output end of the load simulation unit.

9. A test system for a four-wheel steering system based on load simulation, characterized in that, include: The bench test unit is used to install and fix the four-wheel steering system to be tested according to the preset actual vehicle installation method; The load simulation unit is used to apply a preset load to the four-wheel steering system according to a preset load simulation working condition; The four-wheel steering control unit is used to control the response of the four-wheel steering system according to the preset target steering angle command, and to collect the real-time operating parameters of the four-wheel steering system in real time; The data analysis unit is used to compare the real-time operating parameters with preset operating parameters to determine whether the four-wheel steering system is qualified.

10. The four-wheel steering system testing system according to claim 9, characterized in that, Also includes: A safety protection unit is provided, which is used to trigger an alarm signal when the load parameters exceed a first preset warning threshold or the real-time operating parameters exceed a second preset warning threshold.

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