Test system applied to NVH test

Abstract

The embodiment of the invention provides a test system applied to an NVH (Noise Vibration and Harshness) test. Wherein the upper computer is used for determining the input voltage of the magnetic powder brake and adjusting the input voltage of the magnetic powder brake according to actual steering information and target steering information; the tested SWA is used for executing simulation steering operation; and the magnetic powder brake is used for simulating the resistance received by the tested SWA in the steering process and monitoring the actual steering information of the tested SWA in the process of executing the simulated steering operation according to the input voltage in the process of executing the simulated steering operation by the tested SWA. Through the application, the magnetic powder brake is adopted to simulate the steering resistance under different driving behaviors and road conditions, the technical problem that the NVH test result is distorted due to the fact that no actual load is used as the support of the test working condition in the prior art is solved, and it is guaranteed that the test result can more truly reflect the NVH performance of the SWA under the actual use condition.

Description

Technical Field

[0001] The embodiments of the present application relate to the field of NVH testing, and more specifically, to a testing system for NVH testing. Background Art

[0002] At the current stage of integration of electric vehicles and intelligent driving technology, automotive electronic and electrical equipment are undergoing new forms and new application environments with each passing day, and the original mechanical structures of automotive parts are gradually being transformed into electric structures.

[0003] Specifically, taking automotive parts such as wire-controlled steer as an example, it replaces the traditional steering of body parts consisting of universal joints, universal rods and worm gears. It is composed of a motor and a control unit. In simple terms, when driving a motor vehicle, the driver performs flexible steering according to the actual conditions of the driving road. Originally, steering was performed through a universal joint with a certain transmission ratio. Through the rotation of the steering wheel, the universal joint is driven to transmit the steering input to the electronic power booster EPS to amplify the torque and then steer. However, the current SWA (Steer-by-Wire Actuator) is a small transmission shaft directly connected to the steering wheel. When the driver intends to turn, the driver's instructions and intentions are obtained through the angle and torque sensors, and the direction, acceleration and force of the driver's steering wheel rotation are analyzed and collected, and converted into steering linear velocity, angular velocity and steering torque. After calculation and logic processing by the ECU (Electronic Control Unit), it is transmitted to the RWA (Road Wheel Actuator) through the vehicle CAN (Controller Area Network). RWA drives its own mechanical steering structure to output steering action and drive the vehicle to turn. At the same time, RWA transmits data to SWA, and SWA performs road sense feedback through information processing, that is, reverse action with the steering wheel, giving the driver a certain reverse steering torque, prompting the driver to perceive the relationship between the vehicle speed and the resistance of the steering wheel, or the steering wheel slightly shakes, prompting the driver to perceive the bumpy relationship between the vehicle and the roughness of the road surface, or the direction automatically reverses, prompting the driver to perceive the return relationship after the vehicle turns, etc.

[0004] During the traditional NVH (Noise, Vibration, and Harshness) test, the test is conducted directly in the anechoic chamber. At a specific position in the anechoic chamber, the steering wheel is turned. When turning, the tester or test driver is responsible for steering. The NVH test equipment measures and evaluates the noise, vibration and harshness. Since it only focuses on the upper steering work and execution in the cab, the lower steering RWA is only connected to the vehicle CAN network for data signals, and there is no actual mechanical structure connection. In addition, in more cases, RWA and SWA are developed and manufactured by different parts manufacturers. When testing SWA, there is no technical support from RWA, and SWA cannot obtain RWA data during the test. As a result, there is no actual load to support the test conditions during the NVH test, which distorts the results of the NVH test. Summary of the invention

[0005] The embodiment of the present application provides a test system for NVH test, so as to at least solve the technical problem in the related art that there is no actual load as the support of the test condition, resulting in distortion of the NVH test results.

[0006] According to one aspect of an embodiment of the present application, a test system for NVH testing is provided, the system comprising a silencing chamber, a host computer, a magnetic powder brake and a SWA under test, the magnetic powder brake and the SWA under test are placed in the silencing chamber, the host computer is electrically connected to the magnetic powder brake and the SWA under test respectively, and the magnetic powder brake is connected to the SWA under test; wherein,

[0007] The host computer is used to obtain target driving information, target road surface information and target steering information in the NVH test during the execution of an NVH test, and send the target driving information and the target road surface information to the SWA under test; determine the input voltage of the magnetic powder brake according to the target driving information and the target road surface information, and send the determined input voltage to the magnetic powder brake; receive actual steering information sent by the magnetic powder brake, and adjust the input voltage of the magnetic powder brake according to the actual steering information and the target steering information;

[0008] The SWA under test is used to receive the target driving information and the target road surface information, and perform a simulated steering operation according to the target driving information and the target road surface information;

[0009] The magnetic powder brake is used to receive the input voltage sent by the host computer, and provide resistance to the SWA under test according to the input voltage during the process of the SWA under test performing the simulated steering operation, so as to simulate the resistance received by the SWA under test during the steering process; monitor the actual steering information during the process of the SWA under test performing the simulated steering operation, and send the actual steering information to the host computer.

[0010] Through this application, in the process of performing an NVH test, the target driving information, target road surface information and target steering information in the NVH test are obtained, and the SWA under test is controlled to perform a simulated steering operation according to the target driving information and the target road surface information. In the process of the SWA under test performing the simulated steering operation, the resistance provided by the magnetic powder brake is accurately controlled according to the target driving information and the target road surface information, and the steering resistance under different driving behaviors and road conditions is simulated, thereby improving the authenticity and effectiveness of the NVH test. The actual steering information fed back by the magnetic powder brake is compared with the target steering information, and the input voltage of the magnetic powder brake is dynamically adjusted to achieve closed-loop control, thereby improving the accuracy and efficiency of the NVH test. At the same time, the automated control of the host computer reduces the reliance on manual settings and adjustments, improves the automation level of the test, and reduces operational complexity and potential human errors. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 is a structural block diagram of an optional test system applied to NVH test according to an embodiment of the present application;

[0012] Figure 2 is a structural block diagram of another optional test system applied to NVH test according to an embodiment of the present application;

[0013] Figure 3 is a structural block diagram of another optional test system applied to NVH test according to an embodiment of the present application;

[0014] Figure 4 is a schematic diagram of a structure in which an optional SWA to be tested is placed on a rubber sleeper according to an embodiment of the present application;

[0015] Figure 5 is a schematic structural diagram of an optional disturbance rotator according to an embodiment of the present application;

[0016] Figure 6 is a schematic structural diagram of another optional disturbance rotator according to an embodiment of the present application;

[0017] Figure 7 is a front view of an optional disturbance rotator according to an embodiment of the present application;

[0018] Figure 8 is a top view of an optional disturbance rotator according to an embodiment of the present application;

[0019] Fig. 9 is a side view of an optional disturbance rotator according to an embodiment of the present application;

[0020] The following are the descriptions of the reference numerals:

[0021] 41, rubber sleeper; 42, supporting structure; 43, SWA under test;

[0022] 61, claw-carrying fixed disk; 62, claw-carrying rotating disk; 63, bearing locking snap ring; 64, coaxial coupling; 65, bearing; 66, stirring claw. DETAILED DESCRIPTION

[0023] The embodiments of the present application will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0024] It should be noted that the terms "first", "second", etc. in the specification and claims of this application and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence.

[0025] According to one aspect of an embodiment of the present application, a test system for NVH test is provided. Figure 1 is a structural block diagram of an optional test system for NVH testing according to an embodiment of the present application, such as Figure 1 As shown, the system includes an anechoic chamber 102, a host computer 104, a SWA 106 to be tested, and a magnetic powder brake 108. The SWA 106 to be tested and the magnetic powder brake 108 are placed in the anechoic chamber 102. The host computer 104 is electrically connected to the SWA 106 to be tested and the magnetic powder brake 108 respectively, and the SWA 106 to be tested is connected to the magnetic powder brake 108; wherein,

[0026] The host computer 104 is used to obtain target driving information, target road surface information and target steering information in the NVH test during the execution of an NVH test, and send the target driving information and target road surface information to the SWA 106 under test; determine the input voltage of the magnetic powder brake 108 according to the target driving information and the target road surface information, and send the determined input voltage to the magnetic powder brake 108; receive actual steering information sent by the magnetic powder brake 108, and adjust the input voltage of the magnetic powder brake 108 according to the actual steering information and the target steering information.

[0027] It should be noted that NVH testing is a comprehensive test method for the noise, vibration and harshness generated by a vehicle under various operating conditions. These tests are essential for evaluating the comfort and performance of a vehicle, especially during the development phase, to ensure that the vehicle is designed to meet specific NVH standards and enhance the driving and riding experience.

[0028] The host computer is the control and data processing center in the test system, responsible for generating and sending control signals, receiving feedback data, and performing data analysis. In the embodiment of the present application, the host computer is not placed in the anechoic chamber, and can generally be placed in the control room. In the NVH test, the host computer obtains the target driving information, target road surface information and target steering information given in the NVH test, wherein the target driving information refers to the vehicle driving condition parameters preset in the NVH test, which is intended to simulate a specific driving scenario. This information includes but is not limited to driving mode (such as economy mode, sports mode), vehicle speed, engine speed, drive mode (such as four-wheel drive / two-wheel drive), steering information, throttle position, brake force, etc. The target driving information is used to guide the SWA under test to simulate a specific driving behavior, thereby evaluating the NVH performance of the SWA under test in the vehicle under these conditions. In specific practice, the basic information of the steering vehicle chassis control domain where the current SWA under test is located can be configured and simulated according to the target driving information, such as driving sports mode, four-wheel drive / two-wheel drive mode, engine gear, vehicle speed value, brake control logic, etc. These basic information are directly related to the internal logic of SWA steering adjustment. For example, when the driving mode is stopped or idling, SWA is not working; the four-wheel drive / two-wheel drive mode can clarify whether the SWA steering has a rear-wheel drive steering requirement; the engine gear can clarify whether SWA is in a steering-ready state. If it is in P gear or N gear, SWA is in a standby state with no output. The vehicle speed value is similar to the gear information, and the brake control logic is used to determine whether SWA is in a braking deceleration state. It should be noted that when the target driving information indicates that SWA is not in operation, the NVH test is terminated.

[0029] The target road surface information is the road condition parameters simulated in the NVH test, which is used to reflect the driving experience of the vehicle on different road surfaces. This information includes road surface flatness, road surface roughness, and road surface elevation inclination. The setting of the target road surface information helps the test system simulate the NVH response of the vehicle under complex road conditions. The target steering information is the steering operation parameters preset in the test, including the expected steering angle, steering speed, steering torque, etc., which are used to guide the target behavior of the SWA under test when simulating steering operations. Optionally, the target steering information and the steering information in the target driving information can be a set of corresponding relationships determined by a pre-set test outline, that is, in the NVH test, the steering information in the target driving information corresponds to the corresponding target steering information.

[0030] The host computer controls the magnetic powder brake to provide resistance for the SWA under test according to the target driving information and the target road surface information. Specifically, the host computer determines the input voltage of the magnetic powder brake according to the target driving information and the target road surface information, so as to control the magnetic powder brake to provide resistance for the SWA under test by giving the magnetic powder brake an input voltage, and adjusts the input voltage of the magnetic powder brake according to the actual steering information and the target steering information of the SWA under test.

[0031] An anechoic chamber is an enclosed space designed to reduce sound reflection and external noise, and is used for noise collection in NVH tests. The anechoic chamber provides a low-noise environment through sound-absorbing materials, sound-insulating structures, and silencing technology to ensure the accuracy and repeatability of NVH test data. In this embodiment, a magnetic powder brake and a SWA under test are placed in the anechoic chamber to isolate external interference and focus on the collection and analysis of internal NVH signals.

[0032] SWA is a steer-by-wire system that controls vehicle steering through electronic signals rather than traditional mechanical connections. In the NVH test, the SWA under test receives target driving information and target road surface information sent by the host computer, autonomously calculates steering requirements, and performs simulated steering operations.

[0033] The actual steering information refers to the steering angle, steering speed, steering torque and other data actually generated by the SWA under test when performing the simulated steering operation. This information is collected by the sensor of the magnetic powder brake and fed back to the host computer for comparison and adjustment to ensure that the steering operation is consistent with the preset target steering information.

[0034] Exemplarily, the host computer compares the actual steering information with the target steering information, calculates the deviation between the two, and adjusts the input voltage of the magnetic powder brake based on the deviation between the two to optimize the steering behavior of the SWA under test. Optionally, multiple deviations between the actual steering behavior and the target steering behavior are calculated based on the actual steering information and the target steering information, such as angle deviation, speed deviation, and torque deviation. Usually, a closed-loop control algorithm is used, such as proportional integral derivative (PID control). The PID control algorithm dynamically adjusts the input voltage of the magnetic powder brake through three control parameters: proportional, integral, and derivative, to reduce the deviation between the actual steering information and the target steering information.

[0035] The SWA 106 under test is used to receive target driving information and target road surface information, and perform simulated steering operations according to the target driving information and target road surface information.

[0036] Optionally, the SWA under test analyzes the received target driving information and target road surface information to obtain the analysis results, and performs simulated steering operations based on the analysis results, that is, simulating the response and action of the steering system during actual driving. This simulation operation is intended to reproduce the steering behavior of the vehicle under specific driving conditions and road conditions to evaluate and optimize the vehicle's NVH performance.

[0037] Optionally, the simulated steering operation process is designed for NVH testing, which aims to evaluate the vehicle NVH performance, such as steering noise, vibration and harshness, by simulating the steering action in the actual driving experience, including the road resistance encountered during steering, the vehicle dynamic response, etc. Through this simulation, the NVH characteristics of the tested SWA of the vehicle under different driving and road conditions can be obtained, providing a basis for subsequent design optimization and verification.

[0038] The magnetic powder brake 108 is used to receive the input voltage sent by the host computer 104, and provide resistance to the SWA 106 under test according to the input voltage during the process of the SWA 106 under test performing the simulated steering operation, so as to simulate the resistance received by the SWA 106 under test during the steering process; monitor the actual steering information of the SWA 106 under test during the process of performing the simulated steering operation, and send the actual steering information to the host computer 104.

[0039] It should be noted that the magnetic powder brake may be a controllable magnetic powder brake, which is a device that uses a magnetic field to control the braking torque and can accurately simulate the resistance encountered by the vehicle when turning. In this embodiment, the magnetic powder brake adjusts the resistance it generates according to the input voltage sent by the host computer to affect the steering behavior of the SWA under test.

[0040] Specifically, the resistance simulated by the magnetic powder brake can include the internal resistance of the steering system when turning based on the target driving information and the simulated road resistance. The internal resistance of the steering system when turning based on the target driving information mainly comes from the friction and damping effect of the steering system itself during the steering operation, including but not limited to the friction between components such as motors, gears, and couplings. During the simulated steering operation, after the SWA under test receives the target driving information, the magnetic powder brake can simulate the resistance encountered by the steering system under different driving modes, vehicle speeds, etc. by adjusting the input voltage. Road resistance is the friction generated by the contact between the tire and the road surface under different road conditions during the vehicle's driving. In the NVH test, the magnetic powder brake can also adjust the resistance it provides according to the target road information to simulate the external resistance encountered by the vehicle when turning under various road conditions (such as slippery, potholes, roughness, tilt, etc.). This simulation helps to evaluate the NVH performance of the vehicle's steering operation under complex road conditions, including noise, vibration, and ride comfort.

[0041] Optionally, the magnetic powder brake also has a built-in magnetic powder hysteresis device, which is characterized by that after power is turned on, the magnetic powder has a certain resistance, which is proportional to the voltage passed through, linear and uniformly damped. Therefore, by dynamically adjusting the internal magnetic powder distribution and friction state, it can simulate the internal resistance of the steering system and the road resistance, and provide a close to real resistance environment for the SWA under test when performing simulated steering operations, so that the NVH test system can more comprehensively and finely evaluate the NVH performance of the vehicle under different driving and road conditions.

[0042] Exemplarily, the magnetic powder brake can be mechanically connected to the SWA under test, thereby providing resistance to the SWA 106 under test to simulate the resistance received by the SWA 106 under test during the steering process. Optionally, the magnetic powder brake can be mechanically connected to the SWA through a coaxial coupling. The coupling allows torque transmission between the two shafts, while being able to accommodate small axial and radial offsets, ensuring the stability and reliability of the connection. During the test, the magnetic powder brake simulates different road resistances by changing the strength of the internal magnetic field. This resistance will be directly transmitted to the drive shaft of the SWA through the coupling, affecting its steering process.

[0043] Through the embodiments of the present application, in the process of performing an NVH test, the target driving information, target road surface information and target steering information in the NVH test are obtained, and the SWA under test is controlled to perform a simulated steering operation according to the target driving information and the target road surface information. In the process of the SWA under test performing a simulated steering operation, the resistance provided by the magnetic powder brake is accurately controlled according to the target driving information and the target road surface information, and the steering resistance under different driving behaviors and road conditions is simulated, thereby improving the authenticity and effectiveness of the NVH test. The actual steering information fed back by the magnetic powder brake is compared with the target steering information, and the input voltage of the magnetic powder brake is dynamically adjusted to achieve closed-loop control, thereby improving the accuracy and efficiency of the NVH test. At the same time, the automated control of the host computer reduces the reliance on manual settings and adjustments, improves the automation level of the test, and reduces operational complexity and potential human errors.

[0044] In an exemplary embodiment, the host computer 104 is further used to input the target driving information into a preset driving resistance model to obtain a first resistance output by the preset driving resistance model, wherein the preset driving resistance model is used to predict the theoretical steering resistance provided by the driver in response to different driving information; input the target road surface information into the preset road surface resistance model to obtain a second resistance output by the preset road surface resistance model, wherein the preset road surface resistance model is used to predict the theoretical resistance of the road surface to the wheel under different road surface information; determine the input voltage of the magnetic powder brake 108 according to the first resistance, the second resistance and the first preset table, wherein the first preset table is used to record the resistance that can be generated by the magnetic powder brake 108 under different input voltages.

[0045] It should be noted that the preset driving resistance model is used to predict the theoretical steering resistance provided by the driver in response to different target driving information, and the driving information may include driving mode, vehicle speed, four-wheel drive / two-wheel drive mode, engine gear, etc. The preset driving resistance model can be based on the dynamic response of the vehicle under different driving conditions, such as the stiffness and damping of the steering system and the driver's reaction time, so as to accurately predict the theoretical resistance required by the steering system under different driving modes.

[0046] The preset road resistance model is used to predict the theoretical resistance of the road surface to the wheel under different road surface information (such as road surface type, road surface flatness, road surface elevation angle, etc.). The preset road resistance model takes into account the physical characteristics of the tire-ground contact, such as friction coefficient, tire compression and recovery process, and the dynamic response of the vehicle under specific road conditions. Through this model, the theoretical resistance of the wheel under different road conditions such as slippery, potholes, rough or inclined can be predicted.

[0047] The first preset table includes a record of the specific resistance values ​​that the magnetic powder brake can generate under different input voltages. The first preset table is the key to the control of the magnetic powder brake, which enables the host computer to accurately adjust the input voltage of the magnetic powder brake according to the preset resistance requirements, thereby controlling the magnetic powder brake to provide an accurate resistance value.

[0048] Optionally, the first preset table is generated by performing a series of input voltage experiments on the magnetic powder brake under laboratory conditions, measuring and recording the resistance or torque generated by the brake at each voltage, performing data analysis, determining the functional relationship between voltage and resistance, and establishing a preset table corresponding to voltage and resistance based on the voltage-resistance functional relationship, i.e., the first preset table. The table may include multiple voltage-resistance pairs, covering the working range of the magnetic powder brake.

[0049] Exemplarily, the host computer inputs the target driving information into the preset driving resistance model to obtain the first resistance output by the preset driving resistance model, inputs the target road surface information into the preset road surface resistance model to obtain the second resistance output by the preset road surface resistance model, and determines the input voltage of the magnetic powder brake according to the first resistance, the second resistance and the first preset table. Optionally, the first resistance and the second resistance are added (or combined by other mathematical operations according to the specific situation) to obtain the total target resistance of the steering system under the current test conditions. The total target resistance is the resistance value that the magnetic powder brake needs to provide to simulate the real steering resistance and road resistance. According to the total target resistance, the first preset table is searched. If there is no directly matching voltage value in the first preset table, the host computer may need to use linear interpolation to estimate the voltage value closest to the total target resistance.

[0050] After determining the input voltage required by the magnetic powder brake, the host computer sends a control signal for the input voltage to the magnetic powder brake. After receiving the control signal for the input voltage, the magnetic powder brake adjusts the distribution state of its internal magnetic powder according to the input voltage to change the resistance or torque provided. It should be noted that the Hall sensor or other types of sensors in the magnetic powder brake will continuously monitor the actual output resistance to ensure that it matches the resistance in the first preset table corresponding to the voltage value instructed by the host computer.

[0051] Through this embodiment, the preset driving resistance model and the preset road resistance model are based on a large amount of measured data and theoretical analysis, and can predict the theoretical steering resistance generated by the driver's response to different driving information, as well as the theoretical resistance of the road surface to the wheel under different road conditions. These theoretical resistances are converted into the input voltage of the magnetic powder brake through the first preset table, so that the precise resistance control of SWA under simulated driving and road conditions is realized, and the simulation degree of NVH test is enhanced.

[0052] In an exemplary embodiment, the SWA 106 under test includes an ECU, a motor, and a drive shaft, wherein a preset driving scenario model is provided in the ECU, and the preset driving scenario model is used to predict the steering demand of the SWA 106 under different road surface information and driving information; wherein,

[0053] The ECU is used to input the target road surface information and the target driving information into a preset driving scenario model to obtain the target steering demand, and control the motor and the drive shaft to perform the simulated steering operation according to the target steering demand.

[0054] The SWA under test includes an ECU, a motor and a drive shaft. The magnetic powder brake can be mechanically connected to the drive shaft (output shaft) of the SWA through a coaxial coupling. A preset driving scenario model is set in the ECU. When the target driving information (such as driving mode, vehicle speed, engine gear, steering information, etc.) and target road surface information (such as road surface type, road condition, inclination, etc.) received by the SWA under test are analyzed by the ECU in the SWA under test, and the target driving information and target road surface information are input into the preset driving scenario model to predict the corresponding target steering demand, so that the ECU generates a corresponding motor control signal according to the target steering demand to control the motor and the drive shaft to perform a simulated steering operation. After receiving the instruction from the ECU, the motor outputs torque to drive the steering shaft to achieve a predetermined steering angle and speed to adapt to different driving and road conditions and ensure the accuracy and stability of the steering operation. The preset driving scenario model is used to predict the steering demand of the SWA under test under different road surface information and driving information. The steering demand may include steering angle, steering speed and steering torque, etc.

[0055] It should be noted that the preset driving scenario model can be generated based on a large amount of actual driving data. Specifically, the performance data of SWA is collected from a variety of driving scenarios, including but not limited to steering angle, steering torque, vehicle speed, engine status, driving mode, braking status, road surface type, road surface roughness, road surface slipperiness, etc. The collected data is preprocessed, including data cleaning, missing value processing, outlier detection, etc., to ensure the quality of the data. Key features related to steering demand prediction, such as vehicle speed, engine speed, road surface type, etc., are extracted as input parameters of the model. A suitable machine learning algorithm or physics-based model is selected to construct a preset driving scenario model. Common algorithms include but are not limited to support vector machines (SVM), decision trees, random forests, neural networks, or physics-based dynamic models. Using the data processed by feature engineering, the steering demand (steering angle, steering torque) is used as the target output of the model for model training. The data set is divided into a training set and a test set, and the model is trained using the training set data, and the generalization ability of the model is verified by the test set data. The parameters of the model are optimized through cross-validation, grid search and other methods to improve the prediction accuracy. Adjust feature selection, learning rate, regularization terms, etc. to ensure the stability of the model when predicting steering needs.

[0056] Through this embodiment, through the comprehensive use of driving scenario models, the ECU is able to generate steering demands that are extremely close to actual driving conditions, thereby providing highly simulated steering operations in NVH tests.

[0057] In an exemplary embodiment, another test system for NVH testing is provided. Figure 2 is a structural block diagram of another optional test system for NVH test according to an embodiment of the present application, such as Figure 2 As shown, the above system also includes:

[0058] A TAS signal converter 202, wherein the TAS signal converter 202 is placed in the anechoic chamber 102, one end of the TAS signal converter is electrically connected to the host computer 104, and the other end of the TAS signal converter is electrically connected to the magnetic powder brake 108, and the TAS signal converter is used to convert the electrical signal emitted by the magnetic powder brake 108 into a digital signal and transmit it to the host computer 104;

[0059] A first CAN signal transceiver 204, wherein one end of the first CAN signal transceiver is electrically connected to the host computer 104, and the other end of the first CAN signal transceiver is electrically connected to the TAS signal converter;

[0060] The second CAN signal transceiver 206 has one end electrically connected to the host computer 104 and the other end electrically connected to the SWA 106 under test.

[0061] Among them, the TAS signal converter module is responsible for receiving the analog electrical signal emitted by the magnetic powder brake, converting the analog signal into a digital signal, and using an analog-to-digital converter (ADC) to quantize the continuous analog signal into a discrete digital signal for easy processing and analysis by the host computer. Then, the processed digital signal is sent to the host computer through an electrical connection with the first CAN signal transceiver.

[0062] The first CAN signal transceiver acts as a bridge between the TAS signal converter and the host computer, and is responsible for transmitting control signals and status feedback between the two. In the embodiment of the present application, the first CAN signal transceiver encapsulates the received digital signal into a data frame according to the CAN protocol and sends it to the host computer through the CAN bus. At the same time, it is also responsible for receiving the control instructions of the host computer, decapsulating them and sending them to the TAS signal converter, thereby affecting the control logic of the magnetic powder brake.

[0063] The second CAN signal transceiver is responsible for establishing a communication channel between the host computer and the SWA under test. Specifically, it receives the simulated steering signals sent by the host computer, including steering angle, steering torque, etc., encapsulates these signals into data frames according to the CAN protocol, and sends them to the ECU of the SWA through the CAN bus to control the motor and drive shaft in the SWA to perform simulated steering operations.

[0064] Through this embodiment, the TAS signal converter can convert the analog electrical signal emitted by the magnetic powder brake into a digital signal, which not only improves the accuracy of the data, but also facilitates subsequent data processing and analysis. The first CAN signal transceiver and the second CAN signal transceiver use CAN bus technology to achieve real-time communication between the host computer and the TAS signal converter and the SWA under test, so that the control instructions and status feedback can be transmitted in a very short time, forming a high-speed control loop, ensuring real-time control and monitoring of the SWA during the test, and improving the response speed and control accuracy of the NVH test.

[0065] In an exemplary embodiment, the system further comprises:

[0066] The detection module is used to collect NVH information in NVH tests.

[0067] The detection module may include multiple NVH test collectors. Specifically, Figure 3 It is a structural block diagram of another optional test system applied to NVH test according to an embodiment of the present application. The detection module may include an NVH collector 302 located in the area where the host computer is located, a first noise collector 304 located in the anechoic chamber, a second noise collector 306 located in the anechoic chamber, and a vibration collector (not shown in the figure) arranged on the drive shaft of the SWA106 under test.

[0068] Optionally, the NVH collector 302 located in the area where the host computer is located is mainly responsible for monitoring and collecting NVH information of the entire test environment, including but not limited to the background noise level, environmental vibration conditions and acoustic roughness in the test room.

[0069] The first noise collector 304 is used to collect noise signals from the anechoic chamber, especially those related to the operation of the SWA (steer-by-wire actuator) under test. It can capture the noise generated by the operation of the SWA motor, gear meshing, etc., so as to evaluate the noise level and noise characteristics of the SWA, which is a direct measure of the noise aspect of NVH performance.

[0070] The second noise collector 306 is similar to the first noise collector, but it may be placed at a different location to capture noise in different areas of the anechoic chamber or noise of a specific frequency. This allows a comprehensive assessment of the noise impact generated by the SWA at different locations and the propagation characteristics of the noise in space.

[0071] The vibration collector is directly installed on the SWA under test to collect vibration data when the SWA performs steering operations. It can capture the vibration characteristics of components such as steering shafts, motors, gearboxes, etc., including vibration frequency, amplitude, vibration mode, etc.

[0072] Among them, when performing steering operations according to target driving information and target road surface information, the NVH information of SWA is recorded, including a series of noises, steering shaft vibrations and overall acoustic harshness under simulated steering operations. NVH information is used to evaluate the NVH performance of SWA and optimize the test system.

[0073] In specific practice, the data processing and analysis functions of the host computer are used to compare the test results with the preset NVH performance standards. The preset NVH performance standards here are based on the NVH design goals of the vehicle under different working conditions, usually including indicators such as noise level, vibration frequency and amplitude, and roughness evaluation. The NVH test results of SWA did not meet the expected standards, which shows that under the current setting conditions, the NVH performance of SWA is insufficient. Possible reasons include design defects, manufacturing quality problems, improper control strategies, etc.

[0074] Through this embodiment, the NVH performance of SWA in a simulated driving scenario can be accurately evaluated by using the NVH information collected by the detection module in the NVH test.

[0075] In an exemplary embodiment, rubber sleepers are placed on the floor of the anechoic chamber 102 , and the SWA 106 and the magnetic powder brake 108 to be tested are both placed on the rubber sleepers.

[0076] Among them, the rubber sleepers are made of materials with high elasticity, good sound absorption and shock absorption properties. The purpose is to form an isolation layer between the SWA and magnetic powder brake and the ground to reduce the vibration transmission and noise reflection caused by direct contact.

[0077] Anechoic chambers are usually designed as acoustic isolation environments, with the interior walls and floors specially treated to minimize interference from external noise and vibration. The use of rubber sleepers further enhances this isolation effect, providing a more ideal quiet and vibration-reducing environment for NVH testing.

[0078] Through this embodiment, rubber sleepers are placed on the floor of the anechoic chamber, and the SWA and magnetic powder brake to be tested are placed on the rubber sleepers, which provides a more ideal quiet and vibration reduction environment for the NVH test, thereby improving the accuracy of the test results of the NVH test.

[0079] In an exemplary embodiment, the SWA 106 under test and the magnetic powder brake 108 are both placed on a rubber sleeper via a supporting structure, and the supporting structure of the SWA 106 under test and the supporting structure of the magnetic powder brake 108 are connected via a same-frequency resonance rod.

[0080] The SWA and magnetic powder brake under test are placed on the rubber sleeper through the support structure. At the bottom of the support structure, there can be multiple point-distributed rubber pads, which are in direct contact with the rubber sleeper. This design ensures the stable support of the equipment, and at the same time, the shock absorption and sound insulation properties of rubber are used to effectively isolate the vibration and noise during the operation of the equipment.

[0081] The frequency resonance rod is a mechanical connector, one end of which is connected to the output shaft of the SWA and the other end is connected to the input shaft of the magnetic powder brake. This connection method enables the magnetic powder brake to provide real-time resistance simulation according to the steering action of the SWA, while ensuring that the force and vibration transmission between the two are carried out at the same frequency, avoiding unnecessary resonance interference. Optionally, the frequency resonance rod is made of a rigid material, generally carbon steel, which has the advantages of high hardness, uniformity, and high vibration frequency transmission characteristics.

[0082] Specifically, Figure 4 FIG. 1 is a schematic diagram of an optional structure of placing a SWA under test on a rubber sleeper according to an embodiment of the present application. Figure 4 As shown, a rubber sleeper 41, a support structure 42 and a SWA 43 to be tested. In the anechoic chamber, a rubber sleeper 41 is arranged on the ground, and the rubber sleeper 41 supports the SWA 43 to be tested through a plurality of support structures 42. Optionally, the plurality of support structures may not be perpendicular to the ground of the anechoic chamber, i.e., on the rubber sleeper.

[0083] Through this embodiment, based on the connection of the same-frequency resonance rod, the magnetic powder brake can respond to the steering action of the SWA in real time and provide accurate resistance simulation. This connection method ensures the synchronization of resistance and steering action during the test, which is conducive to simulating damping and force feedback under real driving conditions and improving the authenticity and reliability of NVH testing.

[0084] In an exemplary embodiment, the support structure of the SWA 106 under test is a first number of rigid shock-absorbing rods, the support structure of the magnetic powder brake 108 is a second number of rigid shock-absorbing rods, and the same frequency resonance rods connect at least part of the rigid shock-absorbing rods of the SWA 106 under test and at least part of the rigid shock-absorbing rods of the magnetic powder brake 108.

[0085] The rigid shock-absorbing rods supporting the SWA and magnetic powder brake under test are made of high-strength steel or aluminum alloy to ensure the rigidity and stability of the structure. These shock-absorbing rods are generally distributed in a "V" or "X" shape to evenly distribute the weight of the equipment and improve the stability of the support.

[0086] The first number of rigid shock-absorbing rods is used to support the SWA, and the second number of rigid shock-absorbing rods is used to support the magnetic powder brake 108. The first number and the second number are based on the weight, size and expected vibration frequency of the equipment to ensure sufficient support stability and vibration isolation effect. Generally, the first number can be 4 and the second number can be 2.

[0087] The rigid shock absorber rod can be made of rigid material. The hardness is manifested as surface rigidity. The internal and surface amplitudes are different. Generally, aluminum alloy surface hardening treatment is required. It is rigidly connected to SWA and magnetic powder brake respectively, simulating the actual situation of vehicle installation. When SWA is working in the test, its own vibration can be effectively transmitted, simulating the inherent vibration frequency and conduction characteristics of the object, and keeping it as consistent as possible with the actual vehicle.

[0088] Through the present embodiment, the combination of the rigid shock-absorbing rod and the rubber sleeper can effectively isolate the vibration generated during the operation of the SWA and the magnetic powder brake, reduce the transmission of the vibration to the test bench, and thus improve the accuracy of the NVH test.

[0089] In an exemplary embodiment, the magnetic powder brake 108 includes a disturbance rotator including a plurality of agitation claws with grooves and a rotating structure; wherein,

[0090] The stirring claws are in the form of multiple steps, each step having at least one groove, and the multiple stirring claws are fixed on the rotating structure, and the multiple stirring claws are used to rotate and stir the magnetic powder in the magnetic powder brake 108 to generate torque;

[0091] The rotating structure is used for driving the plurality of stirring claws to rotate based on the input voltage of the magnetic powder brake 108 .

[0092] The disturbance rotator may be composed of a plurality of stirring claws with grooves and a rotating structure. The stirring claws are in a multi-step shape, and each step has at least one groove, so that the contact area with the magnetic powder can be increased when the magnetic powder in the magnetic powder brake is rotated and stirred, thereby improving the stirring efficiency, thereby generating torque more effectively during rotation. The plurality of stirring claws are evenly fixed on the rotating structure, ensuring the balance during the rotation process and avoiding additional vibration caused by structural imbalance.

[0093] The grooves can not only hold the magnetic powder, but also the edges of the grooves come into contact with the magnetic powder during the rotation process, generating friction, which is then converted into torque. When the multi-stage stepped agitator claws rotate, the interaction between the grooves of different depths and the magnetic powder can produce a more complex and precise torque output, simulating the changes in resistance to SWA under different road conditions and working conditions.

[0094] The rotation speed and direction of the rotating structure are controlled by the input voltage of the magnetic powder brake. Optionally, the host computer can accurately control the rotation speed of the rotating structure by adjusting the input voltage, thereby controlling the degree of stirring of the magnetic powder by the stirring claws, thereby achieving the purpose of adjusting the torque output. Specifically, Figure 5 It is a schematic structural diagram of an optional disturbance rotator according to an embodiment of the present application.

[0095] Through this embodiment, the multi-stage stepped claw and groove design of the disturbance rotator can accurately generate the preset torque under different input voltages, so that the NVH test can accurately simulate the resistance changes encountered by SWA in actual driving, thereby improving the authenticity and credibility of the test.

[0096] In an exemplary embodiment, a rotation speed sensor is mounted on the disturbance rotator, wherein:

[0097] The rotation speed sensor is used to detect the actual steering information when the SWA106 under test performs a simulated steering operation.

[0098] Among them, a disturbance rotator is provided in the magnetic powder brake, and a speed sensor can be installed on the disturbance rotator. The speed sensor can be used to detect the actual steering information of the SWA under test when the magnetic powder brake provides resistance to the SWA under test according to the input voltage during the process of the SWA under test performing a simulated steering operation.

[0099] Through this embodiment, the speed sensor is used to detect the actual steering information when the SWA under test performs a simulated steering operation, so that the host computer can adjust the input voltage of the magnetic powder brake in time according to the difference between the actual steering information and the target steering information, thereby achieving more accurate resistance control.

[0100] In an exemplary embodiment, Figure 6 is a schematic diagram of the structure of another optional disturbance rotator according to an embodiment of the present application, such as Figure 6 As shown, the rotating structure includes: a claw fixing plate 61, a claw rotating plate 62, a bearing locking ring 63, a coaxial coupling 64 and a bearing 65, and a plurality of stirring claws 66 are fixed on the claw fixing plate 61; wherein,

[0101] One end of the claw-carrying fixed disk 61 is connected to a plurality of stirring claws 66, and the other end is connected to the claw-carrying rotating disk 62. The claw-carrying fixed disk 61 is used to fix the plurality of stirring claws 66;

[0102] One end of the claw-carrying rotating disk 62 is connected to the claw-carrying fixed disk 61, and the other end is connected to the bearing locking clamp 63, wherein the claw-carrying rotating disk 62 is used to drive the coaxial coupling 64 to rotate;

[0103] One end of the bearing locking snap ring 63 is connected to the claw rotating disk 62, and the other end is connected to the coaxial coupling 64;

[0104] One end of the coaxial coupling 64 is connected to a bearing locking ring 63, and the other end is connected to a bearing 65;

[0105] One end of the bearing 65 is fixed on the claw rotating disk 62, and the other end passes through the bearing locking ring 63 and the coaxial coupling 64 in sequence.

[0106] Among them, the claw-carrying fixed disk is a circular disk-shaped structure used to fix and support multiple stirring claws. The claw-carrying fixed disk is connected to multiple stirring claws through one end thereof, and the other end is connected to the claw-carrying rotating disk, so that the stirring claws can firmly maintain their positions during rotation, and can rotate with the claw-carrying rotating disk at the same time. The stirring claws are designed in a multi-stage step form, and each stage has at least one groove for stirring the magnetic powder in the magnetic powder brake. The other end of the claw-carrying fixed disk is connected to the claw-carrying rotating disk through a fastener. When the claw-carrying rotating disk rotates, the stirring claws are driven to rotate together through the claw-carrying fixed disk to achieve stirring of the magnetic powder.

[0107] The claw rotating disk is the rotating part of the disturbance rotator. It is connected to the claw fixed disk at one end and connected to the bearing locking ring at the other end. When the claw rotating disk rotates, it drives the claw fixed disk and the stirring claw fixed on it to rotate together, thereby generating disturbances when the SWA performs steering operations, simulating uneven road surfaces or dynamic changes during driving.

[0108] The bearing locking ring is an annular component used to fix the bearing and the coaxial coupling, and is located at one end of the claw rotating disk. It is connected to the claw rotating disk and ensures that the bearing will not move during rotation, providing stability and support for the rotating structure.

[0109] The coaxial coupling is a component that connects the claw rotating disc and the bearing. Its function is to transmit the rotational motion of the claw rotating disc to the bearing while maintaining the consistency of the rotation axis of the two. The use of the coaxial coupling ensures the smoothness and efficient transmission of the rotational motion.

[0110] Bearings are key components used in rotating structures to reduce friction and wear on the contact surface of rotating parts and to transmit rotary motion. One end of the bearing is fixed to the claw rotating disk, and the other end passes through the bearing locking ring and coaxial coupling to be connected to the external rotating shaft or other mechanical parts. The existence of the bearing ensures the smoothness and reliability of the disturbance rotator during rotation.

[0111] In order to better understand the specific structure of the perturbation rotator, such as Figures 7 to 9 As shown, Figure 7 is a front view of an optional disturbance rotator according to an embodiment of the present application; Figure 8 is a top view of an optional disturbance rotator according to an embodiment of the present application; Fig. 9 is a side view of an optional disturbance rotator according to an embodiment of the present application.

[0112] Through this embodiment, the precise design of the rotating structure, especially the coordination between the claw rotating disk and the claw fixed disk, ensures that the stirring claw can stir the magnetic powder evenly and efficiently during rotation, thereby achieving precise control of the torque to meet the high-precision requirements for simulated resistance in NVH testing.

[0113] Obviously, those skilled in the art should understand that the above modules or steps of the present application can be implemented by a general computing device, they can be concentrated on a single computing device, or distributed on a network composed of multiple computing devices, they can be implemented by a program code executable by a computing device, so that they can be stored in a storage device and executed by the computing device, and in some cases, the steps shown or described can be executed in a different order from that herein, or they can be made into individual integrated circuit modules, or multiple modules or steps therein can be made into a single integrated circuit module for implementation. Thus, the present application is not limited to any specific combination of hardware and software.

[0114] The above are only preferred embodiments of the present application and are not intended to limit the present application. For those skilled in the art, the present application may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the principles of the present application shall be included in the protection scope of the present application.

Claims

1. A test system for NVH test, characterized in that: The system includes a silencing chamber, a host computer, a magnetic powder brake and a SWA under test. The magnetic powder brake and the SWA under test are placed in the silencing chamber. The host computer is electrically connected to the magnetic powder brake and the SWA under test respectively, and the magnetic powder brake is connected to the SWA under test; wherein, The host computer is used to obtain target driving information, target road surface information and target steering information in the NVH test during the execution of an NVH test, and send the target driving information and the target road surface information to the SWA under test; determine the input voltage of the magnetic powder brake according to the target driving information and the target road surface information, and send the determined input voltage to the magnetic powder brake; receive actual steering information sent by the magnetic powder brake, and adjust the input voltage of the magnetic powder brake according to the actual steering information and the target steering information; The SWA under test is used to receive the target driving information and the target road surface information, and perform a simulated steering operation according to the target driving information and the target road surface information; The magnetic powder brake is used to receive the input voltage sent by the host computer, and provide resistance to the SWA under test according to the input voltage during the process of the SWA under test performing the simulated steering operation, so as to simulate the resistance received by the SWA under test during the steering process; monitor the actual steering information during the process of the SWA under test performing the simulated steering operation, and send the actual steering information to the host computer.

2. The system according to claim 1, characterized in that The host computer is further used to input the target driving information into a preset driving resistance model to obtain a first resistance output by the preset driving resistance model, wherein the preset driving resistance model is used to predict the theoretical steering resistance provided by the driver in response to different driving information; input the target road surface information into a preset road surface resistance model to obtain a second resistance output by the preset road surface resistance model, wherein the preset road surface resistance model is used to predict the theoretical resistance of the road surface to the wheel under different road surface information; determine the input voltage of the magnetic powder brake according to the first resistance, the second resistance and a first preset table, wherein the first preset table is used to record the resistance that can be generated by the magnetic powder brake under different input voltages.

3. The system according to claim 1, characterized in that The SWA under test includes an ECU, a motor and a drive shaft, wherein a preset driving scenario model is provided in the ECU, and the preset driving scenario model is used to predict the steering demand of the SWA under test under different road surface information and driving information; wherein, The ECU is used to input the target road surface information and the target driving information into the preset driving scenario model to obtain the target steering requirement, and control the motor and the drive shaft to perform the simulated steering operation according to the target steering requirement.

4. The system according to claim 1, characterized in that The system further comprises: A TAS signal converter, wherein the TAS signal converter is placed in the anechoic chamber, one end of the TAS signal converter is electrically connected to the host computer, and the other end is electrically connected to the magnetic powder brake, and the TAS signal converter is used to convert the electrical signal emitted by the magnetic powder brake into a digital signal and transmit it to the host computer; A first CAN signal transceiver, wherein one end of the first CAN signal transceiver is electrically connected to the host computer, and the other end of the first CAN signal transceiver is electrically connected to the TAS signal converter; A second CAN signal transceiver, wherein one end of the second CAN signal transceiver is electrically connected to the host computer, and the other end of the second CAN signal transceiver is electrically connected to the SWA under test.

5. The system according to claim 4, characterized in that The system further comprises: The detection module is used to collect NVH information in the NVH test.

6. The system according to claim 4, characterized in that A rubber sleeper is placed on the floor of the anechoic chamber, and the SWA to be tested and the magnetic powder brake are both placed on the rubber sleeper.

7. The system according to claim 6, characterized in that The SWA under test and the magnetic powder brake are both placed on the rubber sleeper through a supporting structure, and the supporting structure of the SWA under test and the supporting structure of the magnetic powder brake are connected through a same-frequency resonance rod.

8. The system according to claim 7, characterized in that The support structure of the SWA under test is a first number of rigid shock-absorbing rods, the support structure of the magnetic powder brake is a second number of rigid shock-absorbing rods, and the iso-frequency resonance rod connects at least part of the rigid shock-absorbing rods of the SWA under test and at least part of the rigid shock-absorbing rods of the magnetic powder brake.

9. The system according to any one of claims 1 to 8, characterized in that The magnetic powder brake comprises a disturbance rotator, which comprises a plurality of stirring claws with grooves and a rotating structure; wherein, The stirring claws are in the form of multiple steps, each step has at least one groove, and the multiple stirring claws are fixed on the rotating structure, and the multiple stirring claws are used to rotate and stir the magnetic powder in the magnetic powder brake to generate torque; The rotating structure is used to drive the plurality of stirring claws to rotate based on the input voltage of the magnetic powder brake.

10. The system according to claim 9, characterized in that The rotating structure comprises: a claw-carrying fixed disk, a claw-carrying rotating disk, a bearing locking ring, a coaxial coupling and a bearing, and a plurality of stirring claws are fixed on the claw-carrying fixed disk; wherein, One end of the claw-carrying fixed disk is connected to the plurality of the stirring claws, and the other end is connected to the claw-carrying rotating disk, and the claw-carrying fixed disk is used to fix the plurality of the stirring claws; One end of the claw-carrying rotating disk is connected to the claw-carrying fixed disk, and the other end is connected to the bearing locking clamp ring, wherein the claw-carrying rotating disk is used to drive the coaxial coupling to rotate; One end of the bearing locking snap ring is connected to the claw rotating disk, and the other end is connected to the coaxial coupling; One end of the coaxial coupling is connected to the bearing locking ring, and the other end is connected to the bearing; One end of the bearing is fixed on the claw rotating disk, and the other end passes through the bearing locking clamp ring and the coaxial coupling in sequence.

11. The system according to claim 9, characterized in that The disturbance rotator is equipped with a rotation speed sensor, wherein: The rotation speed sensor is used to detect the actual steering information when the SWA under test performs the simulated steering operation.

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