Excitation force characteristic testing method and device for windscreen wiper system

Abstract

The invention discloses an exciting force characteristic testing method and device for a windscreen wiper system, and relates to the technical field of vehicles, and the method comprises the steps: dividing the windscreen wiper system into three regions, calculating according to the parameter information of the three regions, and obtaining the boundary condition that the real exciting force of the windscreen wiper system is independent of a shock absorber region and a vehicle body region through calculation; building a wiper motor test bench, calibrating a reference point and a target point on the wiper motor test bench, and arranging an acceleration sensor; acquiring a connection point of the wiper motor test bench and the wiper motor, selecting at least one degree-of-freedom direction for beating, and acquiring a transfer function; a wiper motor is started, and vibration response data are obtained through an acceleration sensor; the real exciting force of the wiper motor is obtained based on the vibration response data of the reference point and the transfer function, and the technical problems that in the prior art, different vehicle bodies are matched for wiper system testing in the physical sample vehicle stage, the development period is long, and cost is high can be solved.

Description

Technical Field

[0001] The present invention relates to the technical field of vehicles, and particularly to a method and device for testing the excitation force characteristics of a wiper system. Background Art

[0002] The wiper is one of the indispensable components of an automobile. Its function is to scrape off raindrops and dust attached to the vehicle windshield, improve the visibility of the driver, and keep the windshield clear. However, when the wiper motor works, corresponding vibration impact loads will be generated, and these vibration loads will be transmitted to the vehicle body through the installation points between the wiper motor and the wiper, generating noise, distracting the driver, and affecting driving safety.

[0003] Currently, generally, the NVH index analysis of the wiper system is carried out in the physical prototype stage to reduce the noise of the wiper system. However, the physical prototype needs to be matched with different vehicle bodies of the manufacturer to conduct the vibration and noise performance test of the wiper system, which has a long development cycle, wastes manpower and time costs, and has a relatively high improvement investment cost for matching different vehicle bodies. Summary of the Invention

[0004] Aiming at the deficiencies of the prior art, the purpose of the present invention is to provide a method and device for testing the excitation force characteristics of a wiper system, aiming to solve the technical problems of long development cycle and high cost in the prior art for testing the wiper system by matching different vehicle bodies in the physical prototype stage.

[0005] On the one hand, the present invention provides a method for testing the excitation force characteristics of a wiper system, and the method includes:

[0006] Dividing the wiper system into three regions, namely an excitation source region, a shock absorber region, and a vehicle body region, calculating according to the parameter information of the three regions, deriving predicted acceleration response data, performing true excitation force equivalent substitution on the predicted acceleration response data, and obtaining the boundary conditions of the true excitation force of the wiper system independent of the shock absorber region and the vehicle body region through calculation;

[0007] Building a wiper motor test bench, calibrating a reference point and a target point on the wiper motor test bench, and arranging acceleration sensors at the reference point and the target point respectively;

[0008] Obtaining the connection points between the wiper motor test bench and the wiper motor, respectively hammering at least one degree-of-freedom direction at the connection points, and obtaining the transfer functions of the reference point and the target point;

[0009] Starting the wiper motor, and obtaining the vibration response data of the reference point and the target point through the acceleration sensors;

[0010] Calculate the true excitation force of the wiper motor based on the vibration response data and transfer function of the reference point;

[0011] Verify the accuracy of the true excitation force of the wiper motor based on the vibration response data and transfer function of the target point.

[0012] Compared with the prior art, the beneficial effects of the present invention are as follows: Through the excitation force characteristic test method for the wiper system provided by the present invention, the calculation of the true excitation force of the wiper system derived by regional division is independent of the boundary conditions of the shock absorber area and the vehicle body area. Therefore, the vibration and noise levels can be verified by matching different vehicle bodies at the digital prototype stage without entering the physical prototype stage. Then, by designing a test bench for the wiper motor, measuring the vibration response data and transfer function of the reference point, the true excitation force of the wiper motor is calculated. The method is simple and low-cost. Finally, by measuring the vibration response data and transfer function of the target point, the accuracy of the true excitation force of the wiper motor is verified, improving the accuracy of the true excitation force calculation, thereby solving the technical problems in the prior art of long development cycle and high cost in testing the wiper system by matching different vehicle bodies at the physical prototype stage.

[0013] According to one aspect of the above technical solution, the steps of calculating the true excitation force of the wiper motor based on the vibration response data and transfer function of the reference point specifically include:

[0014] F BLOCKED =[H c -1 a c ,

[0015] where F BLOCKED is the true excitation force of the wiper motor, [H c is the transfer function of the reference point, and a c is the vibration response data of the reference point.

[0016] According to one aspect of the above technical solution, the wiper motor test bench includes a base and a bench provided on the base. The bench includes vertical plates provided at both ends and a connecting plate connecting the two vertical plates. The wiper motor includes a wiper motor body and a connecting rod assembly connected to the wiper motor body. The connecting rod assembly is respectively connected to the two vertical plates to form the connection points.

[0017] According to one aspect of the above technical solution, the reference point is arranged on the vertical plate, and the target point is arranged on the connecting plate.

[0018] ​According to one aspect of the above technical solution, the wiper system is divided into three regions, namely the excitation source region, the shock absorber region, and the vehicle body region. Based on the parameter information of the three regions, the predicted acceleration response data is calculated and derived. By equivalently replacing the predicted acceleration response data with the true excitation force, the step of calculating the true excitation force of the wiper system independently of the boundary conditions of the shock absorber region and the vehicle body region is as follows:

[0019] Divide the wiper system into three regions, namely the excitation source region, the shock absorber region, and the vehicle body region;

[0020] Calibrate the excitation source in the excitation source region, the connection point between the excitation source region and the shock absorber region, the connection point at the interface between the shock absorber region and the vehicle body region, and the measurement point of the required test excitation force characteristics in the vehicle body region as the first point, the second point, the third point, and the fourth point respectively;

[0021] Based on the parameter information of the excitation source region, derive calculation formula one. Based on the parameter information of the shock absorber region, derive calculation formula two. Based on the parameter information of the vehicle body region, derive calculation formula three;

[0022] According to calculation formula one, calculation formula two, and calculation formula three, calculate the predicted acceleration response data at the fourth point;

[0023] Replace the excitation source with an equivalent true excitation force to obtain the predicted acceleration response data after equivalence;

[0024] Based on the predicted acceleration response data after equivalence and the truly measured acceleration response data, calculate that the true excitation force of the wiper system is independent of the boundary conditions of the shock absorber region and the vehicle body region.

[0025] According to one aspect of the above technical solution, the step of deriving calculation formula one based on the parameter information of the excitation source region, deriving calculation formula two based on the parameter information of the shock absorber region, and deriving calculation formula three based on the parameter information of the vehicle body region is as follows:

[0026] Based on the transfer function from the first point to the second point, the self-interface transfer function of the second point, the load generated at the first point, and the acting force generated by the suspension at the second point, derive calculation formula one. The calculation formula is as follows:

[0027]

[0028] Wherein, is the acceleration response data on the active side of the suspension at the second point, [H 21 is the transfer function from the first point to the second point, [H 22The self-interface transfer function for the second point, F s The load generated at the first point, F m The force generated by the suspension at the second point;

[0029] Based on the suspension stiffness at the second point, the suspension frequency, the acceleration response data of the active side of the suspension at the second point, and the acceleration response data of the passive side of the suspension at the third point, calculation formula two is derived, and the calculation formula is as follows:

[0030]

[0031] Among them, F m is the force generated by the suspension at the second point, K is the suspension stiffness at the second point, ω is the suspension frequency at the second point, is the acceleration response data of the passive side of the suspension at the third point;

[0032] Based on the self-interface transfer function of the third point, calculation formula three is derived, and the calculation formula is as follows:

[0033]

[0034] Among them, [H 33 is the self-interface transfer function of the third point.

[0035] According to one aspect of the above technical solution, the steps of calculating the predicted acceleration response data at the fourth point according to calculation formula one, calculation formula two, and calculation formula three specifically include:

[0036] Based on calculation formula one and calculation formula three, a response difference is obtained, and the calculation formula is as follows:

[0037]

[0038] Input the response difference into calculation formula two to obtain the force generated by the suspension at the real second point, and the calculation formula is as follows:

[0039]

[0040] Based on the force generated by the suspension at the real second point, calculate the predicted acceleration response data at the fourth point, and the calculation formula is as follows:

[0041]

[0042] Among them, a pre. is the predicted acceleration response data at the fourth point, [H 43 is the transfer function from the third point to the fourth point.

[0043] According to one aspect of the above technical solution, the step of obtaining the predicted acceleration response data after equivalence by replacing the excitation source with an equivalent true excitation force specifically includes:

[0044] Replace the excitation source with an equivalent true excitation force, and calculate the acceleration response data of the active side of the mount at the second point after equivalence. The calculation formula is as follows:

[0045]

[0046] Based on Formula 2, Formula 3, and the acceleration response data of the active side of the mount at the second point after equivalence, derive the force generated by the mount at the second point after equivalence. The calculation formula is as follows:

[0047] F′ m =-[ω 2 K -1 +([H 22 +[H 33 )] -1 [H 22 F 2；BLOCKED ,

[0048] Based on the force generated by the mount at the second point after equivalence, calculate the predicted acceleration response data after equivalence. The calculation formula is as follows:

[0049] a′ pre. =[H 43 [ω 2 K -1 +([H 22 +[H 33 )] -1 [H 22 F 2；BLOCKED ,

[0050] where a′ pre. is the predicted acceleration response data after equivalence, F 2；BLOCKED is the true excitation force at the second point, is the acceleration response data of the active side of the mount at the second point after equivalence, and F m ′ is the force generated by the mount at the second point after equivalence.

[0051] According to one aspect of the above technical solution, the step of calculating the true excitation force of the wiper system independent of the boundary conditions of the shock absorber area and the body area based on the predicted acceleration response data after equivalence and the actually measured acceleration response data specifically includes:

[0052] Compare the predicted acceleration response data after equivalence with the actually measured acceleration response data. It is found that the predicted acceleration response data after equivalence is the same as the actually measured acceleration response data, and the calculation formula for the predicted acceleration response data after equivalence is equal to the calculation formula for the predicted acceleration response data. Thus, it is calculated that the true excitation force of the wiper system is independent of the boundary conditions of the shock absorber area and the body area. The calculation formula is:

[0053] a pre. = a′ pre.

[0054] [H 43 [ω 2 K -1 +([H 22 +[H 33 )] -1 [H 21 F s =[H 43 [ω 2 K -1 +([H 22 +[H 33 )] -1 [H 22 F 2；BLOCKED .

[0055] F 2；BLOCKED =[H 21 F s [H 22 -1

[0056] Another aspect of the present invention is to provide an excitation force characteristic test device for a wiper system. The device for the excitation force characteristic test of the wiper system is used to implement the above-mentioned excitation force characteristic test method for the wiper system. The device includes:

[0057] A formula derivation module, which is used to divide the wiper system into three regions, namely an excitation source region, a shock absorber region, and a body region, calculate based on the parameter information of the three regions, derive the predicted acceleration response data, perform an equivalent replacement of the true excitation force on the predicted acceleration response data, and calculate that the true excitation force of the wiper system is independent of the boundary conditions of the shock absorber region and the body region;

[0058] A calibration point module, which is used to build a wiper motor test bench, calibrate a reference point and a target point on the wiper motor test bench, and arrange acceleration sensors at the reference point and the target point respectively;

[0059] ​A transfer function acquisition module, configured to obtain connection points between the windshield wiper motor test bench and the windshield wiper motor, respectively select at least one degree-of-freedom direction to hammer at the connection points, and obtain the transfer functions of the reference point and the target point;

[0060] A response data acquisition module, configured to start the windshield wiper motor and acquire vibration response data of the reference point and the target point through an acceleration sensor;

[0061] An excitation force calculation module, configured to calculate the true excitation force of the windshield wiper motor based on the vibration response data and transfer function of the reference point;

[0062] An excitation force verification module, configured to verify the accuracy of the true excitation force of the windshield wiper motor based on the vibration response data and transfer function of the target point. Description of the Drawings

[0063] The above and / or additional aspects and advantages of the present invention will become obvious and easy to understand from the description of the embodiments in conjunction with the following drawings, where:

[0064] Figure 1 It is a schematic flowchart of a method for testing excitation force characteristics of a windshield wiper system in Embodiment 1 of the present invention;

[0065] Figure 2 It is a schematic structural diagram of three regions of a windshield wiper system in Embodiment 1 of the present invention;

[0066] Figure 3 It is a schematic structural diagram of three regions of the windshield wiper system after equivalent replacement in Embodiment 1 of the present invention;

[0067] Figure 4 It is a schematic structural diagram of a windshield wiper motor test bench in Embodiment 1 of the present invention;

[0068] Figure 5 It is a schematic block diagram of a device for testing excitation force characteristics of a windshield wiper system in Embodiment 2 of the present invention;

[0069] Explanation of symbols of components in the drawings:

[0070] The first point 1, the second point 2, the third point 3, the fourth point 4, the windshield wiper motor 5, the reference point 6, the connection point 7, the target point 8, the formula derivation module 100, the calibration point module 200, the transfer function acquisition module 300, the response data acquisition module 400, the excitation force calculation module 500, the excitation force verification module 600;

[0071] The following specific embodiments will further illustrate the present invention in conjunction with the above drawings. Specific Embodiments

[0072] To make the objectives, features, and advantages of the present invention more apparent and understandable, the following provides a detailed description of the specific embodiments of the present invention with reference to the accompanying drawings. Several embodiments of the present invention are shown in the drawings. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, these embodiments are provided to make the disclosure of the present invention more thorough and comprehensive.

[0073] Embodiment 1

[0074] Please refer to Figures 1-4 , a method for testing the excitation force characteristics of a wiper system provided by the first embodiment of the present invention is shown. The method includes steps S10 - S15:

[0075] Step S10, divide the wiper system into three regions, namely the excitation source region, the shock absorber region, and the vehicle body region. Calculate based on the parameter information of the three regions, deduce the predicted acceleration response data, perform an equivalent substitution of the true excitation force on the predicted acceleration response data, and obtain the boundary conditions where the true excitation force of the wiper system is independent of the shock absorber region and the vehicle body region through calculation;

[0076] As Figure 2 shown, in the wiper system, the excitation source region is connected to the vehicle body region through the shock absorber region, and the excitation source region is the relevant components such as the wiper motor.

[0077] Specifically, the step of dividing the wiper system into three regions, namely the excitation source region, the shock absorber region, and the vehicle body region, calculating based on the parameter information of the three regions, deducing the predicted acceleration response data, and performing an equivalent substitution of the true excitation force on the predicted acceleration response data to obtain that the calculation of the true excitation force of the wiper system is independent of the boundary conditions of the shock absorber region and the vehicle body region specifically includes:

[0078] Divide the wiper system into three regions, namely the excitation source region, the shock absorber region, and the vehicle body region;

[0079] Calibrate the excitation source in the excitation source region, the connection point between the excitation source region and the shock absorber region, the connection point at the interface between the shock absorber region and the vehicle body region, and the measurement point of the required test excitation force characteristics in the vehicle body region as the first point 1, the second point 2, the third point 3, and the fourth point 4 respectively;

[0080] Based on the parameter information of the excitation source region, deduce calculation formula 1, based on the parameter information of the shock absorber region, deduce calculation formula 2, and based on the parameter information of the vehicle body region, deduce calculation formula 3;

[0081] Specifically, based on the transfer function from the first point 1 to the second point 2, the self-interface transfer function of the second point 2, the load generated at the first point 1, and the force generated by the suspension at the second point 2, the calculation formula 1 is derived as follows:

[0082]

[0083] Among them, is the acceleration response data of the active side of the suspension at the second point 2, [H 21 is the transfer function from the first point 1 to the second point 2, [H 22 is the self-interface transfer function of the second point 2, F s is the load generated at the first point 1, F m is the force generated by the suspension at the second point 2.

[0084] Based on the suspension stiffness at the second point 2, the suspension frequency, the acceleration response data of the active side of the suspension at the second point 2, and the acceleration response data of the passive side of the suspension at the third point 3, the calculation formula 2 is derived as follows:

[0085]

[0086] Among them, F m is the force generated by the suspension at the second point 2, K is the suspension stiffness at the second point 2, ω is the suspension frequency at the second point 2, is the acceleration response data of the passive side of the suspension at the third point 3.

[0087] Based on the self-interface transfer function of the third point 3, the calculation formula 3 is derived as follows:

[0088]

[0089] Among them, [H 33 is the self-interface transfer function of the third point 3.

[0090] According to the calculation formula 1, the calculation formula 2, and the calculation formula 3, calculate the predicted acceleration response data at the fourth point 4;

[0091] Specifically, based on the calculation formula 1 and the calculation formula 3, the response difference is obtained as follows:

[0092]

[0093] Input the response difference into the calculation formula 2 to obtain the actual force generated by the suspension at the second point 2, as follows:

[0094]

[0095] Calculate the predicted acceleration response data at the fourth point 4 based on the force generated by the suspension at the true second point 2. The calculation formula is as follows:

[0096]

[0097] where a pre. is the predicted acceleration response data at the fourth point 4, and [H 43 is the transfer function from the third point 3 to the fourth point 4.

[0098] As Figure 3 shown, replace the excitation source with an equivalent true excitation force to obtain the predicted acceleration response data after equivalence;

[0099] Specifically, replace the excitation source with an equivalent true excitation force and calculate the acceleration response data of the active side of the suspension at the equivalent second point. The calculation formula is as follows:

[0100]

[0101] Based on Formula 2, Formula 3, and the acceleration response data of the active side of the suspension at the equivalent second point, derive the force generated by the suspension at the equivalent second point. The calculation formula is as follows:

[0102] F′ m = -[ω 2 K -1 + ([H 22 + [H 33 )] -1 [H 22 F 2；BLOCKED ,

[0103] Based on the force generated by the suspension at the equivalent second point, calculate the predicted acceleration response data after equivalence. The calculation formula is as follows:

[0104] a′ pre. = [H 43 [ω 2 K -1 + ([H 22 + [H 33 )] -1 [H 22 F 2；BLOCKED ,

[0105] where a′ pre. is the predicted acceleration response data after equivalence, F 2；BLOCKED is the true excitation force at the second point, is the acceleration response data of the active side of the suspension at the equivalent second point, and F′ mThe force generated by the suspension at the second point after equivalence.

[0106] Calculated based on the predicted acceleration response data after equivalence and the actually measured acceleration response data. It is obtained through calculation that the true excitation force of the wiper system is independent of the boundary conditions of the shock absorber area and the body area.

[0107] Specifically, by comparing the predicted acceleration response data after equivalence with the actually measured acceleration response data, it is obtained that the predicted acceleration response data after equivalence is the same as the actually measured acceleration response data, and the calculation formula for the predicted acceleration response data after equivalence is equal to the calculation formula for the predicted acceleration response data. Thus, it is obtained through calculation that the true excitation force of the wiper system is independent of the boundary conditions of the shock absorber area and the body area. The calculation formula is:

[0108] a pre. =a′ pre.

[0109] [H 43 [ω 2 K -1 +([H 22 +[H 33 )] -1 [H 21 F s =[H 43 [ω 2 K -1 +([H 22 +[H 33 )] -1 [H 22 F 2；BLOCKED 。

[0110] F 2；BLOCKED =[H 21 F s [H 22 -1

[0111] It can be seen that the true excitation force characteristics are only related to the excitation source itself, its own origin transfer function, and the transfer function from the first point 1 to the second point 2. That is, it can be independent of the boundary conditions of the shock absorber area and the body area, and the vibration and noise levels can be verified by matching different bodies at the digital prototype stage.

[0112] However, due to the difficulty in calculating and measuring F s , it is necessary to design a test bench for the wiper motor to measure the true excitation force of the wiper motor.

[0113] ​Step S11: Build a wiper motor test bench, calibrate the reference point and the target point on the wiper motor test bench, and arrange acceleration sensors at the reference point and the target point respectively.

[0114] As Figure 4 shown, the wiper motor test bench includes a base, a bench arranged on the base. The bench includes vertical plates arranged at both ends and a connecting plate connecting the two vertical plates. The wiper motor 5 includes a wiper motor body and a connecting rod assembly connecting the wiper motor. The connecting rod assembly is respectively connected to the two vertical plates to obtain the connection point 7 between the wiper motor test bench and the wiper motor. The reference point 6 is arranged on the vertical plate, and the target point 8 is arranged on the connecting plate.

[0115] Step S12: Obtain the connection points between the wiper motor test bench and the wiper motor, select at least one degree-of-freedom direction to hammer at the connection points respectively, and obtain the transfer functions of the reference point and the target point.

[0116] By way of example rather than limitation, hammer through three degrees-of-freedom directions, namely the three freedom directions of X, Y, and Z.

[0117] Step S13: Start the wiper motor, and obtain the vibration response data of the reference point and the target point through the acceleration sensor.

[0118] By way of example rather than limitation, for example, the wiper motor is connected to an external 12V regulated power supply to make the wiper motor run stably on the bench. At this time, the vibration time-domain data of the reference point and the target point are obtained, and through the FFT fast Fourier transform, the test data are transformed from the time-domain signal into the frequency-spectrum curve of the frequency-domain signal, and the vibration response data of the reference point and the vibration response data of the target point are obtained.

[0119] Step S14: Calculate the true excitation force of the wiper motor based on the vibration response data and transfer function of the reference point.

[0120] F BLOCKED =[H c -1 a c ,

[0121] where F BLOCKED is the true excitation force of the wiper motor, [H c is the transfer function of the reference point, and a c is the vibration response data of the reference point.

[0122] Step S15: Verify the accuracy of the true excitation force of the wiper motor based on the vibration response data and transfer function of the target point.

[0123] ​Specifically, based on the true excitation force of the windshield wiper motor and the transfer function of the target point, the predicted response data of the target point is obtained, and the calculation formula is as follows:

[0124]

[0125] Wherein, is the predicted response data of the target point, [H m is the transfer function of the target point, and F BLOCKED is the true excitation force of the windshield wiper motor.

[0126] By comparing the predicted response data with the measured response data of the target point, the accuracy of the true excitation force of the windshield wiper motor is verified.

[0127] Compared with the prior art, by using the excitation force characteristic test method for the windshield wiper system shown in this embodiment, the calculation of the true excitation force of the windshield wiper system is derived through regional division and is independent of the boundary conditions of the shock absorber area and the body area. Therefore, at the digital prototype stage, different bodies can be matched to verify their vibration and noise levels without entering the physical prototype stage. Then, by designing a test bench for the windshield wiper motor, measuring the vibration response data and transfer function of the reference point, and calculating the true excitation force of the windshield wiper motor, the method is simple and low-cost. Finally, by measuring the vibration response data and transfer function of the target point, the accuracy of the true excitation force of the windshield wiper motor is verified, improving the accuracy of the true excitation force calculation, thereby solving the technical problems of long development cycle and high cost in the prior art for testing the windshield wiper system by matching different bodies at the physical prototype stage.

[0128] Embodiment 2

[0129] Please refer to Figure 5 , which shows an excitation force characteristic test device for a windshield wiper system provided by the second embodiment of the present invention. The device includes:

[0130] A formula derivation module 100, configured to divide the windshield wiper system into three regions, namely an excitation source region, a shock absorber region, and a body region, calculate according to the parameter information of the three regions, derive the predicted acceleration response data, perform an equivalent replacement of the true excitation force on the predicted acceleration response data, and calculate that the true excitation force of the windshield wiper system is independent of the boundary conditions of the shock absorber region and the body region;

[0131] A calibration point module 200, configured to build a test bench for the windshield wiper motor, calibrate a reference point and a target point on the test bench for the windshield wiper motor, and arrange acceleration sensors on the reference point and the target point respectively;

[0132] A transfer function acquisition module 300 is configured to obtain the connection points between the windshield wiper motor test bench and the windshield wiper motor, select at least one degree of freedom direction to hammer at the connection points respectively, and obtain the transfer function of the reference point and the target point;

[0133] A response data acquisition module 400 is configured to start the windshield wiper motor and obtain the vibration response data of the reference point and the target point through an acceleration sensor;

[0134] An excitation force calculation module 500 is configured to calculate the true excitation force of the windshield wiper motor based on the vibration response data and the transfer function of the reference point;

[0135] An excitation force verification module 600 is configured to verify the accuracy of the true excitation force of the windshield wiper motor based on the vibration response data and the transfer function of the target point.

[0136] Compared with the prior art, by using the excitation force characteristic test device for the windshield wiper system shown in this embodiment, the calculation of the true excitation force of the windshield wiper system is derived by a formula derivation module and is independent of the boundary conditions of the shock absorber area and the vehicle body area. Therefore, at the digital prototype stage, different vehicle bodies can be matched to verify their vibration and noise levels without entering the physical prototype stage. Then, by designing a windshield wiper motor test bench, the excitation force calculation module measures the vibration response data and the transfer function of the reference point, calculates the true excitation force of the windshield wiper motor, the method is simple and the cost is low. Finally, the excitation force verification module measures the vibration response data and the transfer function of the target point to verify the accuracy of the true excitation force of the windshield wiper motor, improving the accuracy of the true excitation force calculation, thereby solving the technical problems of long development cycle and high cost in the prior art for testing the windshield wiper system by matching different vehicle bodies at the physical prototype stage.

[0137] The technical features of the above various embodiments can be combined arbitrarily. For the sake of concise description, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, it should be considered as the scope recorded in this specification.

[0138] In the description of this specification, the descriptions with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. mean that the specific features, structures, materials or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in a suitable manner in any one or more embodiments or examples.

[0139] The above-described embodiments merely represent several implementation manners of the present invention. The description thereof is relatively specific and detailed, but it should not be construed as a limitation to the scope of the patent of the present invention. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present invention, several modifications and improvements can still be made, and these all fall within the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be subject to the appended claims.

Claims

1. A method for testing the excitation force characteristics of a wiper system, characterized in that: The method comprises: The wiper system is divided into three regions, namely, an excitation source region, a shock absorber region, and a vehicle body region. The predicted acceleration response data is derived based on the parameter information of the three regions. The predicted acceleration response data is equivalently replaced by the real excitation force. It is calculated that the real excitation force of the wiper system is independent of the boundary conditions of the shock absorber region and the vehicle body region. Building a wiper motor test bench, calibrating a reference point and a target point on the wiper motor test bench, and arranging acceleration sensors at the reference point and the target point respectively; Obtaining the connection points between the wiper motor test bench and the wiper motor, and selecting at least one degree of freedom direction to hammer on the connection points to obtain the transfer function between the reference point and the target point; Starting the wiper motor, and acquiring vibration response data of the reference point and the target point through an acceleration sensor; Calculating the real excitation force of the wiper motor based on the vibration response data and the transfer function of the reference point; Based on the vibration response data and transfer function of the target point, the accuracy of the real excitation force of the wiper motor is verified.

2. The method for testing the excitation force characteristics of a wiper system according to claim 1, characterized in that: The step of calculating the real excitation force of the wiper motor based on the vibration response data and the transfer function of the reference point specifically includes: F BLOCKED =[H c ] -1 a c , Among them, F BLOCKED is the real excitation force of the wiper motor, [H c ] is the transfer function of the reference point, a c is the vibration response data of the reference point.

3. The method for testing the excitation force characteristics of a wiper system according to claim 1, characterized in that: The wiper motor test bench includes a base and a bench arranged on the base, the bench includes vertical plates arranged at both ends and a connecting plate connecting the two vertical plates, the wiper motor includes a wiper motor body and a connecting rod assembly connected to the wiper motor body, and the connecting rod assembly respectively connects the two vertical plates to form the connection point.

4. The method for testing the excitation force characteristics of a wiper system according to claim 3, characterized in that: The reference point is arranged on the vertical plate, and the target point is arranged on the connecting plate.

5. The method for testing the excitation force characteristics of a wiper system according to claim 1, characterized in that: The wiper system is divided into three regions, namely, an excitation source region, a shock absorber region, and a vehicle body region. The predicted acceleration response data is derived based on the parameter information of the three regions. The predicted acceleration response data is equivalently replaced with the real excitation force to obtain the step of calculating the real excitation force of the wiper system independent of the boundary conditions of the shock absorber region and the vehicle body region. Specifically, the step includes: The wiper system is divided into three areas, namely, an excitation source area, a shock absorber area, and a vehicle body area; Calibrate the excitation source of the excitation source area, the connection point between the excitation source area and the shock absorber area, the connection point of the interface between the shock absorber area and the vehicle body area, and the measurement point of the required test excitation force characteristics of the vehicle body area as the first point, the second point, the third point, and the fourth point respectively; Based on the parameter information of the excitation source area, a calculation formula 1 is derived; based on the parameter information of the shock absorber area, a calculation formula 2 is derived; based on the parameter information of the vehicle body area, a calculation formula 3 is derived; According to calculation formula 1, calculation formula 2 and calculation formula 3, the predicted acceleration response data at the fourth point is calculated; Replacing the excitation source with an equivalent real excitation force to obtain equivalent predicted acceleration response data; Based on the equivalent predicted acceleration response data and the actual measured acceleration response data, it is calculated that the actual excitation force of the wiper system is independent of the boundary conditions of the shock absorber area and the body area.

6. The method for testing the excitation force characteristics of a wiper system according to claim 5, characterized in that: The steps of deriving calculation formula 1 based on parameter information of the excitation source region, deriving calculation formula 2 based on parameter information of the shock absorber region, and deriving calculation formula 3 based on parameter information of the vehicle body region specifically include: Based on the transfer function from the first point to the second point, the interface transfer function of the second point, the load generated by the first point, and the force generated by the suspension at the second point, the calculation formula 1 is derived as follows: in, is the acceleration response data of the active side of the suspension at the second point, [H 21 ] is the transfer function from the first point to the second point, [H 22 ] is the interface transfer function of the second point, F s is the load generated at the first point, F m is the force generated by the suspension at the second point; Based on the mount stiffness at the second point, the mount frequency, the acceleration response data of the active side of the mount at the second point, and the acceleration response data of the passive side of the mount at the third point, the calculation formula 2 is derived, and the calculation formula is as follows: Among them, F m is the force generated by the suspension at the second point, K is the suspension stiffness at the second point, ω is the suspension frequency at the second point, is the acceleration response data of the passive side of the suspension at the third point; Based on the interface transfer function of the third point, the calculation formula three is derived, and the calculation formula is as follows: Among them, [H 33 ] is the interface transfer function of the third point itself.

7. The method for testing the excitation force characteristics of a wiper system according to claim 6, characterized in that: The step of calculating the predicted acceleration response data at the fourth point according to calculation formula 1, calculation formula 2, and calculation formula 3 specifically includes: Based on calculation formula 1 and calculation formula 3, the response difference is obtained, and the calculation formula is as follows: The response difference is input into the calculation formula 2 to obtain the actual force generated by the suspension at the second point. The calculation formula is as follows: Based on the actual force generated by the suspension at the second point, the predicted acceleration response data at the fourth point is calculated using the following formula: a pre .=-[H 43 ]F m =[H 43 ][ω 2 K -1 +([H 22 ]+[H 33 ])] -1 [H 21 ]F s , Among them, a pre. is the predicted acceleration response data at the fourth point, [H 43 ] is the transfer function from the third point to the fourth point.

8. The method for testing the excitation force characteristics of a wiper system according to claim 7, characterized in that: The step of replacing the excitation source with an equivalent real excitation force to obtain equivalent predicted acceleration response data specifically includes: The excitation source is replaced with an equivalent real excitation force, and the acceleration response data of the active side of the suspension at the equivalent second point is calculated. The calculation formula is as follows: Based on Formula 2, Formula 3, and the acceleration response data of the active side of the suspension at the equivalent second point, the force generated by the suspension at the equivalent second point is derived, and the calculation formula is as follows: F m ′=-[ω 2 K -1 +([H 22 ]+[H 33 ])] -1 [H 22 ]F 2；BLOCKED , Based on the force generated by the suspension at the equivalent second point, the equivalent predicted acceleration response data is calculated using the following formula: a′ pre. =[H 43 ][ω 2 K -1 +([H 22 ]+[H 33 ])] -1 [H 22 ]F 2；BLOCKED , Among them, a′ pre. is the predicted acceleration response data after equivalent, F 2；BLOCKED For the real motivation on the second point, is the acceleration response data of the active side of the suspension at the second point after equivalent, F m ′ is the force generated by the suspension at the second point after equivalent.

9. The method for testing the excitation force characteristics of a wiper system according to claim 8, characterized in that: Based on the equivalent predicted acceleration response data and the actual measured acceleration response data, the steps of calculating that the actual excitation force of the wiper system is independent of the boundary conditions of the shock absorber area and the vehicle body area include: The equivalent predicted acceleration response data is compared with the actual measured acceleration response data, and it is concluded that the equivalent predicted acceleration response data is the same as the actual measured acceleration response data. The calculation formula of the equivalent predicted acceleration response data is equal to the calculation formula of the predicted acceleration response data. Therefore, it is calculated that the real excitation force of the wiper system is independent of the boundary conditions of the shock absorber area and the body area, and the calculation formula is:

10. A device for testing the excitation force characteristics of a wiper system, characterized in that: The device is used to implement the excitation force characteristic test method for a wiper system according to any one of claims 1 to 9, and the device comprises: A formula derivation module is used to divide the wiper system into three areas, namely, an excitation source area, a shock absorber area, and a vehicle body area, calculate and derive predicted acceleration response data according to parameter information of the three areas, perform equivalent replacement of the predicted acceleration response data with a real excitation force, and calculate that the real excitation force of the wiper system is independent of boundary conditions of the shock absorber area and the vehicle body area; A calibration point module, used for building a wiper motor test bench, calibrating a reference point and a target point on the wiper motor test bench, and arranging acceleration sensors at the reference point and the target point respectively; A transfer function acquisition module, used for acquiring the connection point between the wiper motor test bench and the wiper motor, and selecting at least one degree of freedom direction to hammer on the connection point to acquire the transfer function of the reference point and the target point; A response data acquisition module, used for starting the wiper motor and acquiring vibration response data of the reference point and the target point through an acceleration sensor; an excitation force calculation module, used for calculating the real excitation force of the wiper motor based on the vibration response data and the transfer function of the reference point; The excitation force verification module is used to verify the accuracy of the real excitation force of the wiper motor based on the vibration response data and transfer function of the target point.

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