In-vehicle steering noise subjective evaluation method based on four-wheel independent steering vehicle

Abstract

The invention discloses an in-vehicle steering noise subjective evaluation method based on a four-wheel independent steering vehicle, and relates to the technical field of vehicle noise performance evaluation. The method comprises the steps that test conditions, a test vehicle and evaluation personnel are prepared, and the evaluation personnel sit on the test vehicle; an evaluator subjectively evaluates static working conditions of the test vehicle under the test condition and records score values of subjective evaluation, and the static working conditions comprise a front wheel steering working condition and a four-wheel steering working condition; an evaluator subjectively evaluates the dynamic working conditions of the test vehicle under the test conditions and records score values of the subjective evaluation, and the dynamic working conditions include the oblique running working condition, the crab running working condition, the fixed-point circle winding working condition, the in-situ turning-around working condition and the fixed-point turning-around working condition; and evaluating the noise performance of the test vehicle according to a comparison result of the score value and a set score. According to the method, the noise performance of the vehicle with the four-wheel independent steering system can be subjectively evaluated, and a good guiding effect is provided for NVH performance optimization of the vehicle.

Description

Technical Field

[0001] The invention relates to the technical field of vehicle noise performance evaluation, and in particular to a subjective evaluation method for in-vehicle steering noise based on a four-wheel independent steering vehicle. Background Art

[0002] With the popularization of automobiles, users have higher and higher requirements for various automobile performances, especially noise performance. Automobile noise is inevitable and can only be reduced as much as possible but cannot be completely eliminated. In addition, the frequency components contained in noise are complex, which makes objective testing more difficult. Therefore, subjective evaluation methods can be used to evaluate vehicle noise performance through the subjective feelings of the evaluator.

[0003] At present, with the rapid development of automobile steering technology, automobile companies have developed new technologies for four-wheel independent steering systems. However, the existing noise evaluation methods are mainly aimed at traditional vehicles with two-wheel steering systems and cannot be applied to vehicles with four-wheel independent steering systems. It can be seen that the research on noise evaluation methods for four-wheel independent steering systems is insufficient and still in a blank field. Therefore, it is necessary to formulate good noise performance evaluation standards for vehicles with four-wheel independent steering systems and evaluate the NVH (noise, vibration and harshness, also known as Noise, Vibration, Harshness) performance of four-wheel independent steering systems from the dimension of subjective evaluation. Summary of the invention

[0004] The present invention aims to solve at least one of the technical problems existing in the prior art. To this end, the present invention proposes a subjective evaluation method for in-vehicle steering noise based on a four-wheel independent steering vehicle, which can subjectively evaluate the noise performance of a vehicle with a four-wheel independent steering system and provide good support and guidance for the optimization of the vehicle's NVH performance.

[0005] The embodiment of the present invention provides a subjective evaluation method for in-vehicle steering noise based on a four-wheel independent steering vehicle, which comprises the following steps: preparing test conditions, a test vehicle and an evaluator, wherein the evaluator sits in the test vehicle; The evaluator conducts a subjective evaluation on the static working condition of the test vehicle under the test conditions and records the score value of the subjective evaluation, wherein the static working condition includes the front-wheel steering working condition and the four-wheel steering working condition; The evaluator conducts a subjective evaluation on the dynamic working conditions of the test vehicle under the test conditions and records the score of the subjective evaluation, wherein the dynamic working conditions include oblique driving conditions, crab driving conditions, fixed-point circling conditions, on-the-spot U-turn conditions and fixed-point U-turn conditions; The noise performance of the test vehicle is evaluated based on a comparison result between the score value and a set score.

[0006] The subjective evaluation method for in-vehicle steering noise based on a four-wheel independent steering vehicle according to an embodiment of the present invention has at least the following beneficial effects: after preparing the test vehicle, arranging the evaluation personnel and setting the test conditions, when the test vehicle is respectively operated in the front-wheel steering condition and the four-wheel steering condition, the evaluation personnel sit on the test vehicle and have corresponding subjective feelings to evaluate the in-vehicle noise of the test vehicle under static conditions and give corresponding score values; when the test vehicle is respectively operated in the oblique driving condition, the crab driving condition, the fixed-point circling condition, the on-the-spot U-turn condition and the fixed-point U-turn condition, the evaluation personnel sit on the test vehicle and have corresponding subjective feelings to evaluate the in-vehicle noise of the test vehicle under dynamic conditions and give corresponding score values; after obtaining the score values ​​of the subjective evaluation of the noise of the test vehicle under static conditions and dynamic conditions, the score values ​​are compared with the set scores, and the noise performance of the test vehicle is evaluated according to the comparison results, so as to simulate the actual use conditions of users to the maximum extent, be highly consistent with the user use scenarios, and provide a guiding role in the optimization of NVH performance of vehicles with four-wheel independent steering systems.

[0007] In some embodiments of the present invention, the evaluator performs a subjective evaluation on the static working condition of the test vehicle under test conditions and records the score of the subjective evaluation, including the following steps: In the evaluation of the front wheel steering working condition, a first control instruction of zero position-left turn limit-zero position-right turn limit-zero position is sent to two front wheel steering gears of the test vehicle, and a subjective evaluation of the in-vehicle noise and a score value are recorded during the execution of the first control instruction by the two front wheel steering gears; In the evaluation of the four-wheel steering condition, a second control instruction of zero position-left turn limit-zero position-right turn limit-zero position is sent to the four wheel steering gears of the test vehicle, and a subjective evaluation of the interior noise and a record of the score value are performed during the execution of the second control instruction by the four wheel steering gears.

[0008] In some embodiments of the present invention, the evaluator performs a subjective evaluation on the static working condition of the test vehicle under the test conditions and records the score of the subjective evaluation, and further includes the following steps: Before performing a subjective evaluation on a static working condition of the test vehicle, setting a first speed and a second speed for a wheel steering gear of the test vehicle, wherein the first speed is greater than the second speed; Controlling corresponding wheel steering gears of the test vehicle to respectively execute the first control instruction and the second control instruction according to the first speed; The corresponding wheel steering devices of the test vehicle are controlled to respectively execute the first control instruction and the second control instruction according to the second rotation speed.

[0009] In some embodiments of the present invention, the evaluator performs a subjective evaluation on the dynamic working condition of the test vehicle under test conditions and records the score of the subjective evaluation, including the following steps: In the evaluation of the oblique driving condition, the test vehicle is controlled to drive straight for a certain period of time at a first set speed; Sending a first request instruction for steering according to a first set steering angle to four wheel steering gears of the test vehicle; After the test vehicle executes the first request instruction and travels for a certain period of time, a second request instruction to return to the positive zero position is sent to the test vehicle; The evaluators make subjective evaluations of the in-vehicle noise and record the scores while the test vehicle is driving straight-diagonally-straight.

[0010] In some embodiments of the present invention, the evaluator performs a subjective evaluation on the dynamic working condition of the test vehicle under the test conditions and records the score of the subjective evaluation, and further includes the following steps: In the evaluation of the crab-running condition, the test vehicle is controlled to be in a neutral state, and a third request instruction for steering at a 90° angle is sent to the four wheel steering gears of the test vehicle; After the test vehicle executes the third request instruction, controlling the test vehicle to switch to a forward gear state; After the test vehicle has been driving at the second set speed for a certain period of time, the test vehicle is controlled to stop and switch to a neutral state, and a fourth request instruction for reverse steering at a 90° turning angle is sent to four wheel steering devices of the test vehicle; The evaluators make a subjective evaluation of the in-vehicle noise and record the score while the test vehicle is driving in the process of turning on the spot, crab walking and turning on the spot.

[0011] In some embodiments of the present invention, the evaluator performs a subjective evaluation on the dynamic working condition of the test vehicle under the test conditions and records the score of the subjective evaluation, and further includes the following steps: In the evaluation of the fixed-point circle working condition, the test vehicle is controlled to be in a neutral state, and a fifth request instruction for steering according to a corresponding turning angle is sent to the four wheel steering gears of the test vehicle respectively; After the test vehicle executes the fifth request instruction, controlling the test vehicle to switch to a forward gear state; After the test vehicle drives around the set fixed point at the third set speed for a certain period of time, the test vehicle is controlled to stop and switch to a neutral state, and a sixth request instruction for reverse steering according to the corresponding turning angle is sent to the four wheel steering gears of the test vehicle; The evaluators make a subjective evaluation of the in-vehicle noise and record the score while the test vehicle is driving in the following steps: turning on the spot - circling a fixed point - turning on the spot.

[0012] In some embodiments of the present invention, the evaluator performs a subjective evaluation on the dynamic working condition of the test vehicle under the test conditions and records the score of the subjective evaluation, and further includes the following steps: In the evaluation of the on-the-spot U-turn working condition, the test vehicle is controlled to be in a neutral state, and a seventh request instruction for steering according to corresponding turning angle data is sent to the four wheel steering gears of the test vehicle respectively; After the test vehicle executes the seventh request instruction, controlling the test vehicle to switch to a forward gear state; After the test vehicle makes a U-turn at the fourth set speed for a certain period of time, the test vehicle is controlled to stop and switch to a neutral state, and an eighth request instruction for reverse steering according to the corresponding turning angle data is sent to four wheel steering devices of the test vehicle; The evaluators make a subjective evaluation of the in-vehicle noise and record the score while the test vehicle is driving in the sequence of turning on the spot - making a U-turn on the spot - turning on the spot.

[0013] In some embodiments of the present invention, the evaluator performs a subjective evaluation on the dynamic working condition of the test vehicle under the test conditions and records the score of the subjective evaluation, and further includes the following steps: In the evaluation of the fixed-point U-turn working condition, the test vehicle is controlled to be in a neutral state, and a ninth request instruction for steering according to corresponding turning angle values ​​is sent to three wheel steering devices of the test vehicle; After the test vehicle executes the ninth request instruction, controlling the test vehicle to switch to a forward gear state; After the test vehicle performs a fixed-point U-turn around the contact points between the wheels corresponding to the remaining wheel steering gears and the ground for a certain period of time at the fifth set vehicle speed, the test vehicle is controlled to stop and switch to a neutral state, and a tenth request instruction for reverse steering according to the corresponding steering angle values ​​is sent to three of the wheel steering gears of the test vehicle; The evaluators make a subjective evaluation of the in-vehicle noise and record the score while the test vehicle is driving in the process of turning on the spot, making a fixed-point U-turn, and then turning on the spot.

[0014] In some embodiments of the present invention, the evaluator performs a subjective evaluation on the dynamic working condition of the test vehicle under the test conditions and records the score of the subjective evaluation, and further includes the following steps: Before conducting a subjective evaluation on the dynamic working condition of the test vehicle, setting a third speed for the wheel steering gear of the test vehicle; The corresponding wheel steering devices of the test vehicle are controlled to respectively execute the first request command to the tenth request command according to the third speed.

[0015] In some embodiments of the present invention, after preparing the test conditions, the test vehicle and the evaluator, the following steps are further included: closing the doors, windows, air conditioner, heating device and radio of the test vehicle; And / or, the preparation of test conditions, test vehicles and evaluation personnel includes the following steps: The test conditions were set as background noise below 40dB, the test road surface was dry and flat, and the wind speed at a height of 1.2m above the ground was less than 5m / s; Four evaluators sat in four seats of the test vehicle respectively.

[0016] Other features and advantages of the present invention will be described in the following description, and partly become apparent from the description, or understood by practicing the present invention. The purpose and other advantages of the present invention can be realized and obtained by the structures particularly pointed out in the description, claims and drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 is a flow chart of a subjective evaluation method for in-vehicle steering noise based on a four-wheel independent steering vehicle provided according to an embodiment of the present invention; Figure 2 is a schematic diagram of a specific flow of step S10 in a subjective evaluation method for in-vehicle steering noise based on a four-wheel independent steering vehicle provided in an embodiment of the present invention; Figure 3 is a schematic diagram of a specific flow chart of step S10 in a subjective evaluation method for in-vehicle steering noise based on a four-wheel independent steering vehicle provided according to another embodiment of the present invention; Figure 4 is a schematic diagram of a specific flow of step S20 in a subjective evaluation method for in-vehicle steering noise based on a four-wheel independent steering vehicle provided in an embodiment of the present invention; Figure 5 is a more specific flowchart of step S20 in the subjective evaluation method for in-vehicle steering noise based on a four-wheel independent steering vehicle provided in an embodiment of the present invention; Figure 6 is a specific flow chart of step S310 in the subjective evaluation method for in-vehicle steering noise based on a four-wheel independent steering vehicle provided in an embodiment of the present invention; Figure 7 is a specific flow chart of step S320 in the subjective evaluation method for in-vehicle steering noise based on a four-wheel independent steering vehicle provided in an embodiment of the present invention; Figure 8is a specific flow chart of step S330 in the subjective evaluation method for in-vehicle steering noise based on a four-wheel independent steering vehicle provided in an embodiment of the present invention; Fig. 9 is a specific flow chart of step S340 in the subjective evaluation method for in-vehicle steering noise based on a four-wheel independent steering vehicle provided in an embodiment of the present invention; Fig.10 is a specific flow chart of step S350 in the subjective evaluation method for in-vehicle steering noise based on a four-wheel independent steering vehicle provided in an embodiment of the present invention; Fig.11 is a more specific flowchart of step S30 in the subjective evaluation method for in-vehicle steering noise based on a four-wheel independent steering vehicle provided in an embodiment of the present invention; Fig.12 It is a simplified diagram of the structure with the evaluator sitting on the test vehicle; Fig.13 is a schematic diagram of the wheel status of the test vehicle under static conditions; Fig.13 (a) is a schematic diagram of the wheel status of the test vehicle under the front wheel steering condition; Fig.13 (b) is a schematic diagram of the vehicle state of the test vehicle under four-wheel steering conditions; Fig.14 is a schematic diagram of the wheel status of the test vehicle under dynamic conditions; Fig.14 (a) is a schematic diagram of the wheel status of the test vehicle under straight driving conditions; Fig.14 (b) is a schematic diagram of the wheel status of the test vehicle under the oblique driving condition; Fig.14 (c) is a schematic diagram of the wheel status of the test vehicle under the crab condition; Fig.14 (d) is a schematic diagram of the wheel status of the test vehicle under the fixed-point circular working condition; Fig.14 (e) is a schematic diagram of the wheel status of the test vehicle under the condition of turning on the spot; Fig.14 (f) is a schematic diagram of the wheel status of the test vehicle under fixed-point U-turn conditions.

[0018] Description of reference numerals: 100, test vehicle; 110, seat. DETAILED DESCRIPTION

[0019] Embodiments of the present invention are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and cannot be understood as limiting the present invention.

[0020] In the description of the present invention, it is to be understood that if a feature is defined as "first" or "second", it may explicitly or implicitly include one or more of the features. In the description of the present invention, unless otherwise specified, "plurality" means two or more.

[0021] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "connected" and "connection" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be an indirect connection through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0022] With the popularization of automobiles, users have higher and higher requirements for various automobile performances, especially noise performance. Automobile noise is inevitable and can only be reduced as much as possible but cannot be completely eliminated. In addition, the frequency components contained in noise are complex, which makes objective testing more difficult. Therefore, subjective evaluation methods can be used to evaluate vehicle noise performance through the subjective feelings of the evaluator.

[0023] At present, with the rapid development of automobile steering technology, automobile companies have developed new technologies for four-wheel independent steering systems. Specifically, the power-assisted form of the steering system of passenger cars has been upgraded from non-power-assisted type and hydraulic power-assisted type to electric power-assisted type. According to the different positioning of the vehicle model, the electric power-assisted type can be divided into C-EPS, DP-EPS and R-EPS according to the layout of the power-assisted motor. For high-end passenger cars above Class B, DP-EPS and R-EPS are generally standard. Some super luxury vehicles will be equipped with rear-wheel steering function, which further reduces the turning diameter of the vehicle and greatly improves the steering performance of the vehicle.

[0024] In recent years, the popular wire-controlled steering system has achieved mechanical decoupling of the steering column and steering gear based on the traditional steering system. It not only reduces the layout space and improves the collision safety of the vehicle, but more importantly, it can filter out the impact of the road surface, which not only prevents the driver from feeling the impact but also retains some road feel, greatly improving driving comfort.

[0025] Currently, some leading OEMs and suppliers have researched and developed a new technology for four-wheel independent steering systems. By configuring each wheel steering system with an independent motor controller, the four wheels of the vehicle can rotate independently without interfering with each other. In conjunction with the vehicle's driving system, the vehicle can realize a variety of vehicle steering and driving states, such as turning around on the spot, driving diagonally, crab driving, and circling at a fixed point, thereby greatly improving the vehicle's steering and driving flexibility.

[0026] To date, the traditional steering system technology has been developed to a very mature level, and there are also complete in-vehicle steering noise evaluation standards. However, the existing in-vehicle noise evaluation methods are mainly aimed at traditional vehicles with two-wheel steering systems and cannot be fully applied to vehicles with four-wheel independent steering systems.

[0027] Specifically, traditional vehicle steering technologies basically adopt the front-wheel steering method. The subjective evaluation method of noise of traditional steering systems is concentrated on the driver's position and evaluated. Moreover, the evaluated vehicle working conditions are common on-site steering, low-speed steering, medium- and high-speed steering, etc. For traditional vehicles with front-wheel steering systems, this subjective noise evaluation method can effectively simulate the user's usage needs.

[0028] However, for the four-wheel independent steering system, the above-mentioned subjective noise evaluation method is completely inapplicable. First, the four wheel corner modules of the four-wheel independent steering system are equipped with independent steering gear assemblies, the structure of which mainly includes motors, controllers, speed reduction mechanisms, TAS sensors and housings, etc. Moreover, the steering systems of the four wheels work independently of each other. Obviously, it is not enough to only evaluate the noise level of the driving position; secondly, the four-wheel independent steering system can support the vehicle to complete different steering conditions such as turning around on the spot, driving diagonally, driving crab-like, turning around at a fixed point, and turning around at a fixed point. These conditions are impossible to achieve with traditional vehicle technology, so the conditions in the current subjective noise evaluation method are not applicable to the four-wheel independent steering system.

[0029] It can be seen from the above that for vehicles equipped with four-wheel independent steering systems, the research on in-vehicle noise evaluation methods is insufficient and still in a blank area; considering that the technology of the four-wheel independent steering system will be demonstrated and mass-produced in the future, it is necessary to formulate a good and complete noise performance evaluation standard for vehicles with four-wheel independent steering systems, and evaluate the NVH (noise, vibration and harshness) performance of the four-wheel independent steering system from the dimension of subjective evaluation, so as to provide a good reference for the NVH performance evaluation of future mass-produced models.

[0030] Based on this, an embodiment of the present invention provides a subjective evaluation method for in-vehicle steering noise based on a four-wheel independent steering vehicle, which can subjectively evaluate the noise performance of a vehicle with a four-wheel independent steering system, and provide good support and guidance for the vehicle's NVH performance optimization, thereby filling the technical gap in the subjective evaluation method for vehicle noise for the new technology of the four-wheel independent steering system.

[0031] Reference below Figures 1 to 14 A subjective evaluation method for in-vehicle steering noise based on a four-wheel independent steering vehicle according to an embodiment of the present invention is described.

[0032] like Figures 1 to 14 As shown, the subjective evaluation method for in-vehicle steering noise based on a four-wheel independent steering vehicle according to an embodiment of the present invention can evaluate the in-vehicle noise level of a vehicle equipped with a four-wheel independent steering system, simulate the actual working conditions of the user to the greatest extent, and be highly consistent with the user's usage scenarios, and can provide support for optimizing the noise level of the four-wheel independent steering system.

[0033] like Figure 1 As shown in FIG. 1 , the subjective evaluation method for in-vehicle steering noise based on a four-wheel independent steering vehicle includes the following steps: Step S10 : preparing test conditions, the test vehicle 100 , and an evaluator, wherein the evaluator sits in the test vehicle 100 .

[0034] Step S20: the evaluator performs a subjective evaluation on the static working condition of the test vehicle 100 under the test conditions and records the score of the subjective evaluation, wherein the static working condition includes the front-wheel steering working condition and the four-wheel steering working condition.

[0035] Step S30: the evaluator conducts a subjective evaluation on the dynamic working condition of the test vehicle 100 under the test conditions and records the score of the subjective evaluation, wherein the dynamic working condition includes an oblique driving condition, a crab driving condition, a fixed-point circling condition, an on-the-spot U-turn condition and a fixed-point U-turn condition.

[0036] Step S40: Evaluate the noise performance of the test vehicle 100 according to the comparison result between the score value and the set score.

[0037] Among them, Figure 2 As shown, step S10, i.e., the step of preparing test conditions, test vehicle 100 and evaluation personnel, specifically includes the following steps: Step S101: The test conditions are set as background noise lower than 40 dB, the test road surface is dry and flat, and the wind speed at a height of 1.2 m above the ground is less than 5 m / s.

[0038] Step S102 : Four evaluators sit on four seats of the test vehicle 100 respectively.

[0039] It is understandable that in step S101, a test site needs to be set up for the test vehicle 100, and the conditions of the test site should meet the following conditions: the test road surface should be a flat, seamless asphalt road surface, the test road surface should be dry and free of water accumulation, and the test road surface should not have snow, loose soil or other sound-absorbing materials, so as to avoid the test road surface from interfering with the evaluation of the in-vehicle noise level. The noise performance test and evaluation of the test vehicle 100 should be carried out in good weather.

[0040] In addition, when the test vehicle 100 is conducting a noise evaluation test on the test road surface, there is no other noise interference nearby, and the background noise should be controlled below 40dB to ensure that the noise performance evaluation work is more accurate. The distance between the test vehicle 100 and large objects or other vehicles should be controlled at a certain distance, such as a distance of more than 20m. In addition, the wind speed at a height of 1.2 meters above the ground at the test site should be less than 5m / s to prevent the noise performance evaluation work from being affected by strong winds during the driving of the test vehicle 100, resulting in inaccurate evaluation results.

[0041] In addition, in order to monitor the environmental conditions during the test, meteorological measuring instruments are required. The accuracy of the meteorological measuring instruments must at least meet the following conditions: the temperature measurement accuracy of the temperature measuring equipment is ±1°C, the wind speed measurement accuracy of the wind speed measuring equipment is ±1.0m / s, and the air pressure measurement accuracy of the atmospheric pressure measuring equipment is ±0.5kPa.

[0042] In step S102, the evaluators are professionals with NVH evaluation qualifications or personnel who have received relevant training. The number of evaluators is set to four, namely A, B, C and D. Fig.12 As shown, four evaluators are seated at the left front seat 110, the right front seat 110, the left rear seat 110, and the right rear seat 110 of the test vehicle 100. Of course, the number of evaluators is set according to the number of seats of the test vehicle 100.

[0043] In addition, for the test vehicle 100, the vehicle configuration and technical status should meet the test requirements of the steering system vibration and noise, and ensure that the safety system, oil, electrical and mechanical systems are in a safe state to ensure driving safety. The tires used by the test vehicle 100 should be consistent with the model specified by the automobile manufacturer, the tire pattern should not be obviously worn, the tire pressure should meet the tire pressure requirements specified by the manufacturer, and the tire pressure and roundness should be checked before the test. Secondly, clean up the debris on the test vehicle 100, such as the glove box, storage box, cup holder, luggage box, etc., that is, the test vehicle 100 shall not have any other loads except the evaluator.

[0044] Further, such as Figure 3 As shown, after step S10, i.e., preparing the test conditions, the test vehicle 100 and the evaluator, the following steps are also included: Step S11: closing the doors, windows, air conditioner, heater and radio of the test vehicle 100.

[0045] It is understandable that in step S11, when the test vehicle 100 is in the preparation state, all the evaluators are sitting in the corresponding seats of the test vehicle 100. In order to ensure a more accurate noise level evaluation result, the doors, windows, air conditioners, heating equipment and radio of the test vehicle 100 need to be turned off to avoid noise caused by other factors affecting the noise performance evaluation of the whole vehicle. After completing step S11, the noise performance can be subjectively evaluated for various specific working conditions in the static and dynamic working conditions of the test vehicle 100.

[0046] In this embodiment, the subjective evaluation of the in-vehicle noise level is first performed on the static working condition of the test vehicle 100, and then the subjective evaluation of the in-vehicle noise level is performed on the dynamic working condition of the test vehicle 100. The static working condition includes the front-wheel steering working condition and the four-wheel steering working condition, and the dynamic working condition includes the oblique driving working condition, the crab driving working condition, the fixed-point circle working condition, the on-the-spot U-turn working condition and the fixed-point U-turn working condition. Therefore, it is necessary to perform a subjective evaluation of the noise performance for each specific working condition one by one.

[0047] In some embodiments, Figure 1 and Figure 4 As shown, step S20, i.e., the step in which the evaluator performs a subjective evaluation on the static working condition of the test vehicle 100 under the test conditions and records the score of the subjective evaluation, specifically includes the following steps: Step S21: In the evaluation of the front-wheel steering condition, a first control instruction of zero position-left turn limit-zero position-right turn limit-zero position is sent to the two front-wheel steering gears of the test vehicle 100, and a subjective evaluation of the interior noise and a record of the score value are performed during the execution of the first control instruction by the two front-wheel steering gears.

[0048] Step S22: In the evaluation of the four-wheel steering condition, a second control instruction of zero position-left turn limit-zero position-right turn limit-zero position is sent to the four wheel steering gears of the test vehicle 100, and a subjective evaluation of the interior noise and a record of the score value are performed during the execution of the second control instruction by the four wheel steering gears.

[0049] It is understandable that after all the evaluators sit on the test vehicle 100, they first close the doors, windows, air conditioner, heater and radio, and then test and subjectively evaluate the in-vehicle noise performance for the front wheel steering condition and the four-wheel steering condition of the test vehicle 100. The wheels of the test vehicle 100 may turn left first and then right, or turn right first and then left. Step S21 may be performed before or after step S22.

[0050] In step S21, Fig.13As shown in (a), the evaluator at the driving position can send a first control instruction of zero position-left turn limit-zero position-right turn limit-zero position to the two front wheel steering gears (i.e., front wheel steering gears) of the test vehicle 100 through the vehicle controller, so that the two front wheel steering gears can simultaneously execute the first control instruction issued by the vehicle controller, so that the two front wheels of the test vehicle 100 turn left from the zero position state to the left limit position, then turn right from the left limit position to the zero position state, then turn right from the zero position state to the right limit position, and then turn left from the right limit position to the zero position state; during this process, the two rear wheel steering gears do not move, that is, the rear wheels maintain the zero position state, and in addition, the test vehicle 100 is in a neutral state.

[0051] When the two front wheel steering gears of the test vehicle 100 execute the first control instruction to steer the front wheels, all the evaluators on the test vehicle 100 need to make a subjective evaluation and score the in-vehicle noise generated when the four-wheel independent steering system is working.

[0052] In step S22, if Fig.13 As shown in (b), the evaluator at the driving position can send a second control instruction of zero position-left turn limit-zero position-right turn limit-zero position to the four wheel steering gears of the test vehicle 100 through the vehicle controller, so that the four wheel steering gears can simultaneously execute the second control instruction issued by the vehicle controller, so as to realize that the four wheels (left front wheel, left rear wheel, right front wheel and right rear wheel) of the test vehicle 100 turn left from the zero position state to the left limit position, then turn right from the left limit position to the zero position state, then turn right from the zero position state to the right limit position, and then turn left from the right limit position to the zero position state; during this process, the test vehicle 100 is in a neutral state.

[0053] When the four wheel steering devices of the test vehicle 100 execute the second control instruction to steer all four wheels, all evaluators on the test vehicle 100 need to make subjective evaluations and give scores for the in-vehicle noise generated when the four-wheel independent steering system is working.

[0054] Further, such as Figure 1 , Figure 4 and Figure 5 As shown, step S20, i.e., the step in which the evaluator performs a subjective evaluation on the static working condition of the test vehicle 100 under the test conditions and records the score of the subjective evaluation, further includes the following steps: Step S23: before performing a subjective evaluation on the static working condition of the test vehicle 100 , a first speed and a second speed are set for the wheel steering gear of the test vehicle 100 , wherein the first speed is greater than the second speed.

[0055] Step S24: Control the corresponding wheel steering devices of the test vehicle 100 to respectively execute the first control instruction and the second control instruction according to the first rotation speed.

[0056] Step S25: Control the corresponding wheel steering devices of the test vehicle 100 to respectively execute the first control instruction and the second control instruction according to the second rotation speed.

[0057] It is understandable that before executing step S21 and step S22, step S23 is first executed to set the first speed and the second speed of the wheel steering gear. Since the first speed is greater than the second speed, the action speed of the wheel steering gear of the test vehicle 100, that is, the steering speed of the wheel, can be controlled under static conditions, so that the evaluator can make a subjective evaluation of the in-vehicle noise level for the front wheel steering condition and the four-wheel steering condition of the test vehicle 100 under different conditions of fast wheel steering and slow wheel steering. In this embodiment, the first speed is set to 30° / s, and the second speed is set to 10° / s. Of course, the first speed and the second speed can be set according to the test requirements.

[0058] In the evaluation of the front wheel steering condition, the first control instruction can be executed by the two front wheel steering gears, and the two front wheels can be driven to turn quickly at the first speed. During this process, all the evaluators need to make a subjective evaluation of the noise level inside the vehicle. Then, the first control instruction can be executed by the two front wheel steering gears, and the two front wheels can be driven to turn slowly at the second speed. During this process, all the evaluators need to make a subjective evaluation of the noise level inside the vehicle.

[0059] In the evaluation of the four-wheel steering condition, the second control instruction can be first executed through the four wheel steering gears, and the four wheels can be driven to turn quickly at the first speed. During this process, all evaluators need to make a subjective evaluation of the noise level inside the vehicle. Then, the second control instruction can be executed through the four wheel steering gears, and the four wheels can be driven to turn slowly at the second speed. During this process, all evaluators need to make a subjective evaluation of the noise level inside the vehicle.

[0060] In some embodiments, step S30, i.e. the step in which the evaluator conducts a subjective evaluation on the dynamic working condition of the test vehicle 100 under test conditions and records the score of the subjective evaluation, specifically includes step S310, step S320, step S330, step S340 and step S350.

[0061] Among them, step S310 is for the oblique driving condition of the test vehicle 100, step S320 is for the crab driving condition of the test vehicle 100, step S330 is for the fixed-point circling condition of the test vehicle 100, step S340 is for the on-the-spot U-turn condition of the test vehicle 100, and step S350 is for the fixed-point U-turn condition of the test vehicle 100.

[0062] Specifically, if Figure 1 and Figure 6 As shown, step S30, i.e., the step in which the evaluator performs a subjective evaluation on the dynamic working condition of the test vehicle 100 under the test conditions and records the score of the subjective evaluation, specifically includes the following steps: Step S311: In the evaluation of the oblique driving condition, the test vehicle 100 is controlled to drive straight at a first set vehicle speed for a certain period of time.

[0063] Step S312: Sending a first request instruction to the four wheel steering devices of the test vehicle 100 to perform steering according to a first set steering angle.

[0064] Step S313: After the test vehicle 100 executes the first request instruction and travels for a certain period of time, a second request instruction to return to the positive zero position is sent to the test vehicle 100.

[0065] Step S314: the evaluator makes a subjective evaluation of the noise inside the vehicle and records the score value while the test vehicle 100 is driving in the sequence of straight-diagonal-straight.

[0066] It is understandable that step S310 includes the above-mentioned steps S311 to S314. After all the evaluators sit in the seats of the test vehicle 100, the doors, windows, air conditioner, heater and radio are closed, and then the in-vehicle noise performance is tested and subjectively evaluated for the oblique driving condition of the test vehicle 100.

[0067] The first set vehicle speed, the first set turning angle and the straight-ahead time can be set according to the test requirements. The first set turning angle is greater than 0° and less than 90°. For example, the first set vehicle speed is set to 5km / h and the first set turning angle is set to 20°. Then, the test vehicle 100 is put into the forward gear (i.e., the D gear) and starts straight-ahead from the spot. The straight-ahead speed is 5km / h and the straight-ahead time can be 10s. Fig.14 As shown in (a), the four wheels of the test vehicle 100 are in a neutral state.

[0068] Then, the vehicle controller sends a first request instruction to turn left or right at a turning angle of 20° to each of the four wheel steering gears, so that the four wheel steering gears can simultaneously execute the first request instruction issued by the vehicle controller, so that the four wheels of the test vehicle 100 turn 20° to the left or right, so that the test vehicle 100 is in an oblique driving condition, such as Fig.14 (b) shown.

[0069] After the test vehicle 100 has been driving at an angle for 10 seconds, a second request instruction to return to zero position is sent to the four wheel steering gears of the test vehicle 100 through the vehicle controller. After the four wheel steering gears simultaneously execute the second request instruction, the four wheels of the test vehicle 100 rotate in the opposite direction at an angle of 20°, so that the four wheels return to the zero position state.

[0070] When the test vehicle 100 is traveling in a straight-diagonal-straight mode, all evaluators on the test vehicle 100 are required to conduct subjective evaluation and score the in-vehicle noise generated when the four-wheel independent steering system is operating.

[0071] like Figure 1 and Figure 7 As shown, step S30, i.e., the step in which the evaluator performs a subjective evaluation on the dynamic working condition of the test vehicle 100 under the test conditions and records the score of the subjective evaluation, further includes the following steps: Step S321: During the evaluation of the crab crawling condition, the test vehicle 100 is controlled to be in a neutral state, and a third request instruction for steering at an angle of 90° is sent to the four wheel steering gears of the test vehicle 100.

[0072] Step S322: After the test vehicle 100 executes the third request instruction, the test vehicle 100 is controlled to switch to the forward gear state.

[0073] Step S323: After the test vehicle 100 has been driving at the second set speed for a certain period of time, the test vehicle 100 is controlled to stop and switch to a neutral state, and a fourth request instruction for reverse steering at a 90° angle is sent to the four wheel steering gears of the test vehicle 100.

[0074] Step S324: the evaluator makes a subjective evaluation of the in-vehicle noise and records the score value while the test vehicle 100 is driving in the process of turning on the spot-crab maneuvering-turning on the spot.

[0075] It is understandable that step S320 includes the above-mentioned steps S321 to S324. After all the evaluators are seated on the test vehicle 100, the doors, windows, air conditioner, heater and radio on the test vehicle 100 are first closed, and then the in-vehicle noise performance is tested and subjectively evaluated for the crab-walking condition of the test vehicle 100. The second set speed and the crab-walking time can be set according to the test requirements, for example, the second set speed is set to 5 km / h.

[0076] When the test vehicle 100 is in neutral (i.e., N gear), the vehicle controller sends a third request instruction to turn left or right at an angle of 90° to the four wheel steering gears of the test vehicle 100, so that the four wheel steering gears can simultaneously execute the third request instruction issued by the vehicle controller, prompting the four wheels of the test vehicle 100 to turn 90° to the left or right, thereby realizing on-the-spot turning of the test vehicle 100.

[0077] After adjusting the angles of the four wheels, the test vehicle 100 is controlled to switch from the neutral gear state to the forward gear state, and the test vehicle 100 is driven to perform crab crawling at the second set vehicle speed. The crab crawling time may be 10 seconds. At this time, the test vehicle 100 is in the crab crawling condition, such as Fig.14 (c) shown.

[0078] After the test vehicle 100 has been driving in the crab crawl condition for a period of time, the evaluator in the driving seat first controls the test vehicle 100 to stop, and switches the test vehicle 100 from the forward gear state to the neutral gear state, and then sends a fourth request instruction to turn in the opposite direction at a 90° angle to the four wheel steering gears of the test vehicle 100 through the vehicle controller. After the four wheel steering gears simultaneously execute the fourth request instruction, the four wheels of the test vehicle 100 will rotate in the opposite direction at a 90° angle until the four wheels of the test vehicle 100 return to the zero position.

[0079] When the test vehicle 100 is driving in the working condition of turning on the spot-crab driving-turning on the spot, all the evaluators on the test vehicle 100 need to make a subjective evaluation and score the in-vehicle noise generated when the four-wheel independent steering system is working.

[0080] like Figure 1 and Figure 8 As shown, step S30, i.e., the step in which the evaluator performs a subjective evaluation on the dynamic working condition of the test vehicle 100 under the test conditions and records the score of the subjective evaluation, further includes the following steps: Step S331: In the evaluation of the fixed-point circle condition, the test vehicle 100 is controlled to be in a neutral state, and a fifth request instruction for steering according to a corresponding turning angle is sent to the four wheel steering gears of the test vehicle 100 respectively.

[0081] Step S332: After the test vehicle 100 executes the fifth request instruction, the test vehicle 100 is controlled to switch to the forward gear state.

[0082] Step S333: After the test vehicle 100 drives in a fixed circle around a set fixed position at a third set speed for a certain period of time, the test vehicle 100 is controlled to stop and switch to a neutral state, and a sixth request instruction is sent to the four wheel steering devices of the test vehicle 100 to perform reverse steering according to the corresponding turning angle.

[0083] Step S334: the evaluator makes a subjective evaluation of the in-vehicle noise and records the score value while the test vehicle 100 is driving in the process of turning on the spot - driving in a fixed-point circle - turning on the spot.

[0084] It is understandable that step S330 includes the above-mentioned steps S331 to S334. After all the evaluators are seated on the test vehicle 100, the doors, windows, air conditioner, heating equipment and radio on the test vehicle 100 are closed, and then the test and subjective evaluation of the in-vehicle noise performance for the fixed-point circle condition of the test vehicle 100 are started. The third set speed and the time for the fixed-point circle driving can be set according to the test requirements, for example, the third set speed is set to 5km / h.

[0085] When the test vehicle 100 is in a neutral state, the evaluator can send a fifth request instruction to the four wheel steering devices of the test vehicle 100 respectively according to the corresponding turning angle through the vehicle controller, so that the four wheel steering devices can simultaneously execute the fifth request instruction issued by the vehicle controller, prompting the two front wheels to turn the corresponding turning angle in the same direction, and at the same time, the two rear wheels to turn the corresponding turning angle in the same direction, and the rotation directions of the front wheels and the rear wheels are opposite. For example, if the front wheels turn left, the rear wheels turn right. Fig.14 (d) shown.

[0086] Since the test vehicle 100 is to travel in a fixed-point circle, the turning angles of the four wheels are not exactly the same, and therefore, the turning angles of the corresponding wheels driven by each wheel steering device are different. The setting position of the fixed point can be selected according to the test situation. In this embodiment, the fixed point is selected at a position 1m in front of the left rear wheel and 3m to the left. The position of the fixed point is different, and the turning angles of each wheel of the test vehicle 100 will also change accordingly.

[0087] After adjusting the angles of the four wheels, the test vehicle 100 is controlled to switch from the neutral gear state to the forward gear state, and the test vehicle 100 is driven to perform a fixed-point circular driving at a third set speed. The time for the fixed-point circular driving may be 10 seconds. At this time, the test vehicle 100 is in a fixed-point circular driving condition, such as Fig.14 (d) shown.

[0088] After the test vehicle 100 has been driving in a fixed circle for a period of time, the test vehicle 100 is controlled to stop driving and switched from the forward gear state to the neutral gear state. Then, the vehicle controller sends a sixth request instruction to the four wheel steering gears of the test vehicle 100 to steer in the opposite direction according to the corresponding turning angle. After the four wheel steering gears simultaneously execute the sixth request instruction, the four wheels of the test vehicle 100 will rotate in the opposite direction according to the corresponding turning angle until the four wheels of the test vehicle 100 return to the zero position.

[0089] During the process of the test vehicle 100 driving in the steps of turning on the spot - circling around a fixed point - turning on the spot, all the evaluators on the test vehicle 100 need to make a subjective evaluation on the in-vehicle noise generated when the four-wheel independent steering system is working, and give corresponding subjective evaluation score values.

[0090] like Figure 1 and Fig. 9 As shown, step S30, i.e., the step in which the evaluator performs a subjective evaluation on the dynamic working condition of the test vehicle 100 under the test conditions and records the score of the subjective evaluation, further includes the following steps: Step S341: During the evaluation of the on-the-spot U-turn condition, the test vehicle 100 is controlled to be in a neutral state, and a seventh request instruction for steering according to corresponding steering angle data is sent to the four wheel steering gears of the test vehicle 100 respectively.

[0091] Step S342: After the test vehicle 100 executes the seventh request instruction, the test vehicle 100 is controlled to switch to the forward gear state.

[0092] Step S343: After the test vehicle 100 makes a U-turn on the spot at the fourth set speed for a certain period of time, the test vehicle 100 is controlled to stop and switch to a neutral state, and an eighth request instruction for reverse steering according to corresponding turning angle data is sent to the four wheel steering gears of the test vehicle 100.

[0093] Step S344: the evaluator makes a subjective evaluation of the in-vehicle noise and records the score value while the test vehicle 100 is driving in the process of turning on the spot - turning on the spot - turning on the spot.

[0094] It is understandable that step S340 includes the above-mentioned steps S341 to S344. After all the evaluators sit in the seats of the test vehicle 100, the doors, windows, air conditioners, heating equipment and radio on the test vehicle 100 are all closed, and then the test and subjective evaluation of the in-vehicle noise performance for the turn-on-the-spot condition of the test vehicle 100 can be started. The fourth set speed and the turn-on-the-spot driving time can be set according to the test requirements, and are not specifically limited here. The fourth set speed can be set to 5km / h.

[0095] When the test vehicle 100 is in a neutral state, the vehicle controller sends a seventh request instruction for steering according to the corresponding turning angle data to the four wheel steering gears of the test vehicle 100, so that the four wheel steering gears can respectively execute the seventh request instruction issued by the vehicle controller, prompting the left front wheel and the right rear wheel to rotate the corresponding turning angle data in the same direction. At the same time, the left rear wheel and the right front wheel rotate the corresponding turning angle data in the same direction, and the rotation directions of the left front wheel and the left rear wheel are opposite. For example, the left front wheel and the right rear wheel both turn right, and the left rear wheel and the right front wheel both turn left. Fig.14 (e) shown.

[0096] The line between the center of the left front wheel and the center of the right rear wheel is set as the first line, and the line between the center of the left rear wheel and the center of the right front wheel is set as the second line. The intersection between the first line and the second line is the point for turning around on the spot, and the intersection is approximately the center position of the test vehicle 100.

[0097] After the angles of the four wheels are adjusted, the test vehicle 100 is controlled to change from the neutral gear state to the forward gear state, and the test vehicle 100 is driven to make a U-turn on the spot at the fourth set vehicle speed. The time for the U-turn on the spot can be 10 seconds. At this time, the test vehicle 100 is in the U-turn on the spot condition, such as Fig.14 (e) shown.

[0098] After the test vehicle 100 has been driving in an on-the-spot U-turn condition for a certain period of time, the test vehicle 100 is controlled to stop driving, and the test vehicle 100 is driven to change from the forward gear state to the neutral gear state. Then, the vehicle controller is used to send the eighth request instruction to the four wheel steering gears of the test vehicle 100 to turn in the opposite direction according to the corresponding steering angle data. After the four wheel steering gears respectively execute the eighth request instruction, the four wheels of the test vehicle 100 will rotate in the opposite direction according to the corresponding steering angle data until the four wheels of the test vehicle 100 are returned to the zero position state.

[0099] During the process of the test vehicle 100 driving in a rotation mode, a U-turn and a rotation mode, all the evaluators on the test vehicle 100 need to make a subjective evaluation on the in-vehicle noise generated when the four-wheel independent steering system is working, and give corresponding subjective evaluation scores.

[0100] like Figure 1 and Fig.10 As shown, step S30, i.e., the step in which the evaluator performs a subjective evaluation on the dynamic working condition of the test vehicle 100 under the test conditions and records the score of the subjective evaluation, further includes the following steps: Step S351: In the evaluation of the fixed-point U-turn condition, the test vehicle 100 is controlled to be in a neutral state, and a ninth request instruction for steering according to corresponding steering angle values ​​is sent to three wheel steering gears of the test vehicle 100.

[0101] Step S352: After the test vehicle 100 executes the ninth request instruction, the test vehicle 100 is controlled to switch to the forward gear state.

[0102] Step S353: After the test vehicle 100 makes a fixed-point U-turn around the contact points between the wheels corresponding to the remaining wheel steering gears and the ground for a certain period of time at the fifth set vehicle speed, the test vehicle 100 is controlled to stop and switch to a neutral state, and a tenth request instruction is sent to three of the wheel steering gears of the test vehicle 100 to perform reverse steering according to the corresponding steering angle values.

[0103] Step S354: the evaluator makes a subjective evaluation of the in-vehicle noise and records the score value while the test vehicle 100 is driving in the process of turning on the spot - making a fixed-point U-turn - turning on the spot.

[0104] It is understandable that step S350 includes the above-mentioned steps S351 to S354. After all the evaluators sit in the corresponding seats of the test vehicle 100, the doors, windows, air conditioners, heating equipment and radio are all closed, and then the evaluators can start to test the in-vehicle noise performance and subjectively evaluate the fixed-point U-turn working condition of the test vehicle 100. The fifth set speed, the time of the fixed-point U-turn and the point of the fixed-point U-turn can be selected according to the actual test requirements, for example, the fifth set speed is set to 5km / h.

[0105] In this embodiment, the fixed-point U-turn point is set at the tire contact point of the left front wheel, that is, the left front wheel does not perform active steering, and the left rear wheel, the right front wheel and the right rear wheel all perform active steering.

[0106] When the test vehicle 100 is in a neutral state, the vehicle controller sends a ninth request instruction for steering according to corresponding turning angle values ​​to three of the wheel steering gears of the test vehicle 100 (in this embodiment, the three wheel steering gears corresponding to the left rear wheel, the right front wheel and the right rear wheel), so that the three wheel steering gears can respectively execute the ninth request instruction issued by the vehicle controller, so that the left rear wheel, the right front wheel and the right rear wheel can rotate the corresponding turning angle values. At this time, the wheel corresponding to the remaining wheel steering gear is the left front wheel, and the left front wheel is in a zero position state, such as Fig.14 (f) shown.

[0107] After the wheel angles are adjusted, the test vehicle 100 is controlled to switch from the neutral state to the forward gear state, and the test vehicle 100 is driven to make a fixed-point U-turn around the contact point between the left front wheel and the ground at the fifth set vehicle speed. The fixed-point U-turn driving time may be 10 seconds. At this time, the test vehicle 100 is in a fixed-point U-turn working condition, such as Fig.14 (f) shown.

[0108] After the test vehicle 100 has been driving in a fixed-point U-turn condition for a period of time, the test vehicle 100 is controlled to stop, and the forward gear state of the test vehicle 100 is switched to a neutral state. Then, the vehicle controller is used to send a tenth request instruction to three of the wheel steering gears of the test vehicle 100 to perform reverse steering according to corresponding steering angle values. After the three wheel steering gears respectively execute the tenth request instruction, three of the wheels of the test vehicle 100 (i.e., the left rear wheel, the right front wheel, and the right rear wheel) will rotate in the opposite direction according to the corresponding steering angle values ​​until they return to the straight position, so that all the wheels of the test vehicle 100 are in a zero position state.

[0109] During the process of the test vehicle 100 driving in the steps of turning on the spot - making a fixed-point U-turn - turning on the spot, all the evaluators on the test vehicle 100 need to make a subjective evaluation on the in-vehicle noise generated when the four-wheel independent steering system is working, and give corresponding subjective evaluation score values.

[0110] Further, such as Figure 1 and Fig.11 As shown, step S30, i.e., the step in which the evaluator performs a subjective evaluation on the dynamic working condition of the test vehicle 100 under the test conditions and records the score of the subjective evaluation, further includes the following steps: Step S361: before performing a subjective evaluation on the dynamic working condition of the test vehicle 100 , a third rotation speed is set for the wheel steering gear of the test vehicle 100 .

[0111] Step S362: Control the corresponding wheel steering gears of the test vehicle 100 to respectively execute the first request instruction to the tenth request instruction according to the third speed.

[0112] It can be understood that before conducting a subjective evaluation of the in-vehicle noise level of the test vehicle 100 under the oblique driving condition, crab driving condition, fixed-point circling condition, on-the-spot U-turn condition and fixed-point U-turn condition, the evaluator can set a third speed for the wheel steering gear of the test vehicle 100 through the vehicle controller. The value of the third speed can be set according to the test requirements. For example, the third speed can be set to 30° / s.

[0113] After the third speed is set, when the corresponding wheel steering gear of the test vehicle 100 executes the first request instruction, the second request instruction, the third request instruction, the fourth request instruction, the fifth request instruction, the sixth request instruction, the seventh request instruction, the eighth request instruction, the ninth request instruction and the tenth request instruction, the steering speed of the wheels of the test vehicle 100 must be controlled according to the third speed.

[0114] In step S40, by implementing the above steps, the scores of all evaluators' subjective evaluations of the interior noise of the test vehicle 100 under static and dynamic conditions can be obtained. The scores of the subjective evaluations can be based on a percentage system or a ten-point system.

[0115] In this embodiment, the subjective evaluation of the noise level in the vehicle is scored using a 10-point system, and the minimum unit of the evaluation score is 0.5 points. If necessary, 0.25 points can also be used as the minimum unit.

[0116] The level description table of subjective evaluation is shown in Table 1. Table 1 is as follows:

[0117] All evaluators make subjective evaluations on the in-vehicle noise conditions for each specific operating condition of the test vehicle 100 and give scores according to the conditions in Table 1.

[0118] The score table of working condition evaluation is shown in Table 2. Table 2 is as follows:

[0119] After completing the subjective evaluation of all working conditions, fill in the corresponding scores of the subjective evaluation of all evaluators in Table 2 above, take the average of the scores of all evaluators for each working condition, and use the average score as the final score of the subjective evaluation of the working condition. Generally speaking, if the average score of a certain working condition is ≥6, the in-car noise performance of the test vehicle 100 under this working condition is at a qualified level; if the average score of a certain working condition is <6, the in-car noise performance of the test vehicle 100 under this working condition is at an unqualified level and unacceptable, and the NVH performance of the four-wheel independent steering system needs to be optimized. After optimization, it is necessary to re-perform the subjective evaluation of the in-car noise performance until the in-car noise performance meets the development requirements. The set score can be set according to the actual situation. In this embodiment, the set score is 6.

[0120] The subjective evaluation method for in-vehicle steering noise based on a four-wheel independent steering vehicle in an embodiment of the present invention is applicable to a four-wheel independent steering system, and identifies the above steering conditions based on the characteristics of the four-wheel independent steering system, thereby avoiding problems such as incomplete coverage of user usage scenarios due to inadequate recognition and failure to highly match user usage conditions.

[0121] The above seven working conditions cover the steering modes of static and dynamic conditions of vehicles suitable for four-wheel independent steering systems. The subjective evaluation method of in-vehicle steering noise is highly consistent with the actual usage scenarios of users, which has guiding significance for the mass production and development of four-wheel independent steering technology in the future.

[0122] It can be understood that in the subjective evaluation method for in-vehicle steering noise based on a four-wheel independent steering vehicle provided in an embodiment of the present invention, after preparing the test vehicle 100, arranging the evaluation personnel and setting the test conditions, when the test vehicle 100 is operated in the front-wheel steering condition and the four-wheel steering condition respectively, the evaluation personnel sit on the test vehicle 100 and have corresponding subjective feelings to evaluate the in-vehicle noise of the test vehicle 100 under static conditions and give corresponding score values; when the test vehicle 100 is operated in the oblique driving condition, the crab driving condition, the fixed-point circling condition, the on-the-spot U-turn condition and the fixed-point U-turn condition respectively, the evaluation personnel sit on the test vehicle 100 and have corresponding subjective feelings to evaluate the in-vehicle noise of the test vehicle 100 under dynamic conditions and give corresponding score values.

[0123] After obtaining the subjective noise evaluation score of the test vehicle 100 under static and dynamic conditions, the score is compared with the set score, and the noise performance of the test vehicle 100 is evaluated based on the comparison result, simulating the user's actual usage conditions to the maximum extent, which is highly consistent with the user's usage scenarios and can provide guidance for the NVH performance optimization of vehicles with four-wheel independent steering systems.

[0124] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "illustrative embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.

[0125] Although the embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the claims and their equivalents.

Claims

1. A subjective evaluation method for in-vehicle steering noise based on a four-wheel independent steering vehicle, characterized in that: The steps include: preparing test conditions, a test vehicle and an evaluator, wherein the evaluator sits in the test vehicle; The evaluator conducts a subjective evaluation on the static working condition of the test vehicle under the test conditions and records the score value of the subjective evaluation, wherein the static working condition includes the front-wheel steering working condition and the four-wheel steering working condition; The evaluator conducts a subjective evaluation on the dynamic working conditions of the test vehicle under the test conditions and records the score of the subjective evaluation, wherein the dynamic working conditions include oblique driving conditions, crab driving conditions, fixed-point circling conditions, on-the-spot U-turn conditions and fixed-point U-turn conditions; The noise performance of the test vehicle is evaluated based on a comparison result between the score value and a set score.

2. The subjective evaluation method for in-vehicle steering noise based on a four-wheel independent steering vehicle according to claim 1, characterized in that: The evaluator conducts a subjective evaluation on the static working condition of the test vehicle under the test conditions and records the score value of the subjective evaluation, including the following steps: In the evaluation of the front wheel steering working condition, a first control instruction of zero position-left turn limit-zero position-right turn limit-zero position is sent to two front wheel steering gears of the test vehicle, and a subjective evaluation of the in-vehicle noise and a score value are recorded during the execution of the first control instruction by the two front wheel steering gears; In the evaluation of the four-wheel steering condition, a second control instruction of zero position-left turn limit-zero position-right turn limit-zero position is sent to the four wheel steering gears of the test vehicle, and a subjective evaluation of the interior noise and a record of the score value are performed during the execution of the second control instruction by the four wheel steering gears.

3. The subjective evaluation method for in-vehicle steering noise based on a four-wheel independent steering vehicle according to claim 2, characterized in that: The evaluator conducts a subjective evaluation on the static working condition of the test vehicle under the test conditions and records the score value of the subjective evaluation, which also includes the following steps: Before performing a subjective evaluation on a static working condition of the test vehicle, setting a first speed and a second speed for a wheel steering gear of the test vehicle, wherein the first speed is greater than the second speed; Controlling corresponding wheel steering gears of the test vehicle to respectively execute the first control instruction and the second control instruction according to the first speed; The corresponding wheel steering devices of the test vehicle are controlled to respectively execute the first control instruction and the second control instruction according to the second rotation speed.

4. The subjective evaluation method for in-vehicle steering noise based on a four-wheel independent steering vehicle according to claim 1, characterized in that: The evaluator conducts a subjective evaluation on the dynamic working condition of the test vehicle under the test conditions and records the score value of the subjective evaluation, including the following steps: In the evaluation of the oblique driving condition, the test vehicle is controlled to drive straight for a certain period of time at a first set speed; Sending a first request instruction for steering according to a first set steering angle to four wheel steering gears of the test vehicle; After the test vehicle executes the first request instruction and travels for a certain period of time, a second request instruction to return to the positive zero position is sent to the test vehicle; The evaluators make subjective evaluations of the in-vehicle noise and record the scores while the test vehicle is driving straight-diagonally-straight.

5. The subjective evaluation method for in-vehicle steering noise based on a four-wheel independent steering vehicle according to claim 4, characterized in that: The evaluator conducts a subjective evaluation on the dynamic working condition of the test vehicle under the test conditions and records the score value of the subjective evaluation, which also includes the following steps: In the evaluation of the crab-running condition, the test vehicle is controlled to be in a neutral state, and a third request instruction for steering at a 90° angle is sent to the four wheel steering gears of the test vehicle; After the test vehicle executes the third request instruction, controlling the test vehicle to switch to a forward gear state; After the test vehicle has been driving at the second set speed for a certain period of time, the test vehicle is controlled to stop and switch to a neutral state, and a fourth request instruction for reverse steering at a 90° turning angle is sent to four wheel steering devices of the test vehicle; The evaluators make a subjective evaluation of the in-vehicle noise and record the score while the test vehicle is driving in the process of turning on the spot, crab walking and turning on the spot.

6. The subjective evaluation method for in-vehicle steering noise based on a four-wheel independent steering vehicle according to claim 5, characterized in that: The evaluator conducts a subjective evaluation on the dynamic working condition of the test vehicle under the test conditions and records the score value of the subjective evaluation, which also includes the following steps: In the evaluation of the fixed-point circle working condition, the test vehicle is controlled to be in a neutral state, and a fifth request instruction for steering according to a corresponding turning angle is sent to the four wheel steering gears of the test vehicle respectively; After the test vehicle executes the fifth request instruction, controlling the test vehicle to switch to a forward gear state; After the test vehicle drives around the set fixed point at the third set speed for a certain period of time, the test vehicle is controlled to stop and switch to a neutral state, and a sixth request instruction for reverse steering according to the corresponding turning angle is sent to the four wheel steering gears of the test vehicle; The evaluators make a subjective evaluation of the in-vehicle noise and record the score while the test vehicle is driving in the following steps: turning on the spot - circling a fixed point - turning on the spot.

7. The subjective evaluation method for in-vehicle steering noise based on a four-wheel independent steering vehicle according to claim 6, characterized in that: The evaluator conducts a subjective evaluation on the dynamic working condition of the test vehicle under the test conditions and records the score value of the subjective evaluation, which also includes the following steps: In the evaluation of the on-the-spot U-turn working condition, the test vehicle is controlled to be in a neutral state, and a seventh request instruction for steering according to corresponding turning angle data is sent to the four wheel steering gears of the test vehicle respectively; After the test vehicle executes the seventh request instruction, controlling the test vehicle to switch to a forward gear state; After the test vehicle makes a U-turn at the fourth set speed for a certain period of time, the test vehicle is controlled to stop and switch to a neutral state, and an eighth request instruction for reverse steering according to the corresponding turning angle data is sent to four wheel steering devices of the test vehicle; The evaluators make a subjective evaluation of the in-vehicle noise and record the score while the test vehicle is driving in the sequence of turning on the spot - making a U-turn on the spot - turning on the spot.

8. The subjective evaluation method for in-vehicle steering noise based on a four-wheel independent steering vehicle according to claim 7, characterized in that: The evaluator conducts a subjective evaluation on the dynamic working condition of the test vehicle under the test conditions and records the score value of the subjective evaluation, which also includes the following steps: In the evaluation of the fixed-point U-turn working condition, the test vehicle is controlled to be in a neutral state, and a ninth request instruction for steering according to corresponding turning angle values ​​is sent to three wheel steering devices of the test vehicle; After the test vehicle executes the ninth request instruction, controlling the test vehicle to switch to a forward gear state; After the test vehicle performs a fixed-point U-turn around the contact points between the wheels corresponding to the remaining wheel steering gears and the ground for a certain period of time at the fifth set vehicle speed, the test vehicle is controlled to stop and switch to a neutral state, and a tenth request instruction for reverse steering according to the corresponding steering angle values ​​is sent to three of the wheel steering gears of the test vehicle; The evaluators make a subjective evaluation of the in-vehicle noise and record the score while the test vehicle is driving in the process of turning on the spot, making a fixed-point U-turn, and then turning on the spot.

9. The subjective evaluation method for in-vehicle steering noise based on a four-wheel independent steering vehicle according to claim 8, characterized in that: The evaluator conducts a subjective evaluation on the dynamic working condition of the test vehicle under the test conditions and records the score value of the subjective evaluation, which also includes the following steps: Before conducting a subjective evaluation on the dynamic working condition of the test vehicle, setting a third speed for the wheel steering gear of the test vehicle; The corresponding wheel steering devices of the test vehicle are controlled to respectively execute the first request command to the tenth request command according to the third speed.

10. The subjective evaluation method for in-vehicle steering noise based on a four-wheel independent steering vehicle according to claim 1, characterized in that: After preparing the test conditions, the test vehicle and the evaluator, the following steps are also included: closing the doors, windows, air conditioner, heating equipment and radio of the test vehicle; And / or, the preparation of test conditions, test vehicles and evaluation personnel includes the following steps: The test conditions were set as background noise below 40dB, the test road surface was dry and flat, and the wind speed at a height of 1.2m above the ground was less than 5m / s; Four evaluators sat in four seats of the test vehicle respectively.

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