A method and apparatus for predicting a chassis stone-knocking sound evaluation in a vehicle

Abstract

A kind of chassis stone knocking sound evaluation method and device in car is predicted, belong to chassis test technical field.Step S1, third microphone carries out the collection and knock the knocking sound of the knocking point on the bottom guard plate;Step S2, change the angle of bottom guard plate and ground, repeat step S1-S2;Step S3, formulate the sound transmission function ATF2 of the car to be developed;Step S4, the sound transmission function ATF2 of the car to be developed is simulated using anechoic chamber-anechoic test room set, the sound transmission function ATF3 between first anechoic chamber and second anechoic chamber is measured;Step S5, adjust the position of sound insulation part, first sound source and first microphone, the sound transmission function ATF3 between first anechoic chamber and second anechoic chamber is measured, whether the sound transmission function ATF3 and the sound transmission function ATF2 are similar, if yes, then execute step S6, if no, then execute step S5;Step S6, after playing multiple knocking sound using first sound source, it is scored;Step S7, replace bottom guard plate, repeat step S1-S7, complete the evaluation of the knocking sound of the car to be developed.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of chassis test, in particular to a method for evaluating chassis pebble knocking sound in a vehicle. BACKGROUND

[0002] In the process of developing a vehicle, it is necessary to evaluate the pebble knocking sound to ensure the comfort of the sound when passing through a gravel road. Different underbody shields made of different materials, thicknesses and hardness, or without underbody shields, the sound is larger when pebbles directly hit the metal panel, and the sound is different when a layer of PVC is sprayed.

[0003] In the early stage of development, there is no test vehicle, but it is necessary to consider whether to add an underbody shield and which type of underbody shield to select, or to spray a thick layer of PVC without adding an underbody shield. Currently, there is no method for predicting the noise in the vehicle.

[0004] In summary, the prior art cannot predict the pebble knocking sound generated by different configurations of the vehicle bottom in the early stage of development to select the underbody shield. SUMMARY

[0005] The present application solves the problem that the prior art cannot predict the pebble knocking sound generated by different configurations of the vehicle bottom in the early stage of development to select the underbody shield.

[0006] The method for evaluating the chassis pebble knocking sound in a vehicle, comprising the following steps:

[0007] Step S1, adjusting the aperture of the hourglass to make the pebbles leak out at a constant speed, then opening the third microphone to collect the knocking sound of the knocking point on the underbody shield;

[0008] Step S2, adjusting the length of the telescopic rod to change the angle between the underbody shield and the ground, then repeating steps S1-S2 to obtain multiple knocking sounds;

[0009] Step S3, in a semi-anechoic chamber, formulating the sound transmission function ATF2 of the vehicle to be developed according to the sound transmission function ATF1 measured by the reference vehicle;

[0010] Step S4, simulating the sound transmission function ATF2 of the vehicle to be developed using an anechoic chamber-anechoic test room set, arranging a first sound source in the first anechoic chamber, a first microphone, a test window and a sound insulation part in the second anechoic chamber, and measuring the sound transmission function ATF3 between the first anechoic chamber and the second anechoic chamber using the first sound source and the first microphone;

[0011] Step S5, after adjusting the positions of the sound insulation member, the first sound source and the first microphone respectively, the sound transmission function ATF3 between the first sound absorption chamber and the second sound absorption chamber is measured again by using the first sound source and the first microphone, and it is judged whether the sound transmission function ATF3 is similar to the sound transmission function ATF2 obtained in step S3, if yes, step S6 is executed, if not, step S5 is executed;

[0012] Step S6, the multiple knocking sounds obtained in step S2 are played by the first sound source respectively, and the knocking sounds are scored respectively, the average value of the scoring results is obtained, and the average value is compared and analyzed with the objective data;

[0013] Step S7, after replacing the bottom guard plate, steps S1-S7 are repeated, and the evaluation of the chassis stone knocking sound of the to-be-developed vehicle is completed.

[0014] Further, in an embodiment of the present application, the angle between the bottom guard plate and the ground in step S2 includes 30°, 40°, 50°, 60°, 70° and 80°.

[0015] Further, in an embodiment of the present application, in step S3, the sound transmission function ATF1 measured for the reference vehicle is specifically:

[0016] A second microphone is arranged at a specified position of the reference vehicle, and a second sound source is arranged at the left ear of the driver, and the sound transmission function ATF1 between the specified position of the reference vehicle and the left ear of the driver is measured.

[0017] Further, in an embodiment of the present application, the specified position of the reference vehicle is behind the front left wheel of the reference vehicle, and is 1m-1.5m away from the vertical plane passing through the center of the front wheel.

[0018] The second microphone is 0.1m-0.15m away from the ground.

[0019] The device for evaluating the chassis stone knocking sound in the vehicle of the present application is any one of the above-mentioned methods for predicting the chassis stone knocking sound in the vehicle, and the device comprises an hourglass, a support, an extension rod, a third microphone and a tripod.

[0020] The hourglass is fixed on the support.

[0021] One end of the extension rod supports the bottom guard plate, so that the bottom guard plate forms an angle with the ground.

[0022] The hourglass is located directly above the bottom guard plate, and a distance is formed between the bottom end of the hourglass and the knocking point on the bottom guard plate.

[0023] The third microphone is fixed on the tripod.

[0024] The third microphone is spaced apart from the line connecting the knocking point on the bottom guard plate by a distance, and forms an angle with the bottom guard plate.

[0025] Further, in an embodiment of the present application, the distance between the bottom end of the hourglass and the knocking point on the bottom guard plate is 1.5-1.6 m.

[0026] Further, in an embodiment of the present application, the distance between the third microphone and the line connecting the knocking point on the bottom guard plate is 20-20.5 cm.

[0027] Further, in an embodiment of the present application, the angle between the third microphone and the bottom guard plate is 45°.

[0028] The electronic device comprises a processor, a communication interface, a memory and a communication bus, wherein the processor, the communication interface and the memory complete mutual communication through the communication bus.

[0029] The memory is used for storing a computer program.

[0030] The processor is used for executing the program stored on the memory, and realizes the method steps of any of the above methods.

[0031] The computer readable storage medium stores a computer program, and the computer program is executed by the processor to realize the method steps of any of the above methods.

[0032] The present application solves the problem that the prior art cannot predict the stone knocking sound generated by different configurations of the vehicle bottom in the early development stage to select the bottom guard plate.

[0033] The evaluation method for predicting the stone knocking sound of the chassis in the vehicle comprises the following steps: collecting noise through a bench test, collecting and setting a target of a transmission path characteristic, and then simulating the noise in the vehicle in a sound attenuation room-sound attenuation test room set, so as to predict the stone knocking sound generated by different configurations of the vehicle bottom in the early development stage to select the bottom guard plate.

[0034] The evaluation method for predicting the stone knocking sound of the chassis in the vehicle can be applied to all vehicle models to be developed. BRIEF DESCRIPTION OF DRAWINGS

[0035] The above and / or additional aspects and advantages of the present application will become apparent and more readily appreciated from the following description of the embodiments, taken in conjunction with the accompanying drawings, in which:

[0036] Figure 1 is a chassis stone knock sound device structure in a vehicle according to the embodiment;

[0037] Figure 2 is a microphone installation diagram on a target vehicle according to the embodiment;

[0038] Figure 3 is a sound absorption chamber-sound absorption test chamber set according to the embodiment;

[0039] In the figure, 1 is a stone, 2 is an hourglass, 3 is a support, 4 is a bottom guard plate, 5 is an extension rod, 6 is a ground, 7 is a third microphone, 8 is a tripod, 9 is a knocking point, 10 is a second microphone, 11 is a second sound source, 12 is a sound absorption chamber-sound absorption test chamber set, 13 is a test window, 14 is a sound insulation piece, 15 is a first sound source, and 16 is a first microphone. EMBODIMENT

[0040] The various embodiments of the present application will be described below in detail with reference to the accompanying drawings. The embodiments described by reference to the accompanying drawings are exemplary and are intended to explain the present application, and cannot be understood as limiting the present application.

[0041] The evaluation method for predicting the chassis stone knock sound in a vehicle according to the embodiment includes the following steps:

[0042] Step S1, after adjusting the aperture of the hourglass 2 to make the stone 1 leak out at a constant speed, opening the third microphone 7 to collect the knocking sound of the stone 1 knocking the knocking point 9 on the bottom guard plate 4;

[0043] Step S2, after adjusting the length of the extension rod 5 to change the angle between the bottom guard plate 4 and the ground 6, repeating steps S1-S2 to obtain multiple knocking sounds;

[0044] Step S3, in a semi-sound absorption chamber, formulating the sound transfer function ATF2 of the vehicle to be developed according to the sound transfer function ATF1 measured from the target vehicle;

[0045] Step S4, simulating the sound transfer function ATF2 of the vehicle to be developed using the sound absorption chamber-sound absorption test chamber set 12, arranging the first sound source 15 in the first sound absorption chamber, arranging the first microphone 16, the test window 13, and the sound insulation piece 14 in the second sound absorption chamber, respectively, and measuring the sound transfer function ATF3 between the first sound absorption chamber and the second sound absorption chamber using the first sound source 15 and the first microphone 16;

[0046] Step S5, after adjusting the positions of the sound insulator 14, the first sound source 15 and the first microphone 16 respectively, the sound transmission function ATF3 between the first sound deadening chamber and the second sound deadening chamber is measured again by using the first sound source 15 and the first microphone 16, and it is determined whether the sound transmission function ATF3 is similar to the sound transmission function ATF2 obtained in step S3, if yes, step S6 is executed, if not, step S5 is executed;

[0047] Step S6, the multiple times of knocking sounds obtained in step S2 are played by the first sound source 15 respectively, and the multiple times of knocking sounds are scored respectively, the average value of the scoring results is obtained, and the average value is compared and analyzed with the objective data;

[0048] Step S7, after replacing the bottom guard plate 4, steps S1-S7 are repeated, and the evaluation of the chassis stone knocking sound of the to-be-developed vehicle is completed.

[0049] In the embodiment, the angle between the bottom guard plate 4 and the ground 6 in step S2 includes 30°, 40°, 50°, 60°, 70° and 80°.

[0050] In the embodiment, the sound transmission function ATF1 measured in step S3 is specifically:

[0051] The second microphone 10 is arranged at the specified position of the benchmark vehicle, and the second sound source 11 is arranged at the left ear of the driver, and the sound transmission function ATF1 between the specified position of the benchmark vehicle and the left ear of the driver is measured.

[0052] In the embodiment, the specified position of the benchmark vehicle is behind the front left wheel of the benchmark vehicle, and is 1m-1.5m away from the vertical plane of the center of the front wheel.

[0053] The second microphone 10 is 0.1m-0.15m away from the ground.

[0054] The embodiment is based on the evaluation method for predicting the chassis stone knocking sound in the vehicle according to the application, and provides an actual implementation manner:

[0055] First step: bottom guard plate 4 device: one end of a certain type of bottom guard plate 4 is placed on the ground 6, and the other end is supported by the telescopic rod 5, and the angle between the bottom guard plate 4 and the ground 6 is 30°.

[0056] Second step: stone 1 device: about 100g of relatively uniform stones 1 are swept on the road under the stone 1 knocking sound test condition, then a sandglass 2 with adjustable aperture is found, the stones 1 are poured into the sandglass, then the sandglass 2 is fixed on the support 3, and the distance between the bottom end of the sandglass 2 and the knocking point 9 is 1.5m.

[0057] Step 3: Sound acquisition device: Fix the third microphone 7 on the telescopic tripod 8, keep the line connecting the third microphone 7 and the striking point 9 at 20cm, and the angle between it and the bottom guard plate 4 at 45°.

[0058] Step 4: Collecting tapping sounds: Adjust the aperture of hourglass 2 so that the stones 1 leak out of hourglass 2 at a relatively uniform speed. Then, turn on the third microphone 7 to collect near-field tapping sounds. Adjust the length of the telescopic rod 5 so that the angle between the bottom guard plate 4 and the ground 6 is 40°, 50°, 60°, 70°, and 80° respectively, and collect tapping sounds once each, for a total of 6 times.

[0059] Step 5: Vehicle noise transmission characteristics acquisition and target setting: such as Figure 2 As shown, in a semi-anechoic chamber, a second microphone 10 is placed behind the left front wheel of the benchmark vehicle, 1m away from the vertical plane of the center of the front wheel. The second microphone 10 is 0.1m above the ground. A second sound source 11 for volume acceleration is placed at the driver's left ear. The acoustic transfer function ATF1 between the left front wheel of the benchmark vehicle and the driver's left ear is measured, and the acoustic transfer function ATF2 of the development vehicle is determined in combination with other factors. ATF testing usually adopts the reciprocity method, that is, the sound source excitation point is placed at the human ear, and the microphone test point is placed at the actual sound source.

[0060] Step 6: Simulation of noise transmission characteristics: such as Figure 3 As shown, in the anechoic chamber-anechoic test chamber set 12, the test window 13 is equipped with a sound insulation component 14 made of "sheet metal + PUR foam". Then, a first sound source 15 is arranged in one anechoic chamber and a first microphone 16 is arranged in the other anechoic chamber. The sound transmission function ATF3 between one anechoic chamber and another anechoic chamber is measured. The thickness of the sheet metal and PUR sound insulation component and the position of the first sound source 15 and the first microphone 16 are adjusted. The sound transmission function ATF3 between one anechoic chamber and another anechoic chamber is measured again until the ATF3 curve is similar to ATF2. Then the adjustment and testing are stopped.

[0061] Step 7: Evaluation of the sound of pebble 1 striking the ground: Play six sounds of pebble 1 striking the ground using the first sound source 15. Then, have an evaluator hold their ear close to the first microphone 16 and give a subjective score for each sound. Averaging the six subjective scores gives the overall score for the sound of pebble 1 striking the ground of the bottom guard plate 4. Simultaneously, objective data can be collected using the first microphone 16 for comparative analysis.

[0062] Step 8: By using different underbody protection plates 4, steps 1 to 8 can be completed, and a plan for the stone impact zone under the vehicle can be formulated in the early stage of development.

[0063] The device is a device for predicting the chassis stone knocking sound in the vehicle, which adopts the evaluation method for predicting the chassis stone knocking sound in the vehicle.

[0064] The hourglass 2 is fixed on the support 3.

[0065] The end of the telescopic rod 5 supports the bottom guard plate 4, so that the bottom guard plate 4 forms an angle with the ground 6.

[0066] The hourglass 2 is located directly above the knocking point 9 on the bottom guard plate 4, and the bottom end of the hourglass 2 is away from the knocking point 9 on the bottom guard plate 4 by a distance.

[0067] The third microphone 7 is fixed on the tripod 8.

[0068] The third microphone 7 is away from the knocking point 9 on the bottom guard plate 4 by a distance, and forms an angle with the bottom guard plate 4.

[0069] In this embodiment, the distance between the bottom end of the hourglass 2 and the knocking point 9 on the bottom guard plate 4 is 1.5m-1.6m.

[0070] In this embodiment, the distance between the third microphone 7 and the knocking point 9 on the bottom guard plate 4 is 20cm-20.5cm.

[0071] In this embodiment, the angle between the third microphone 7 and the bottom guard plate 4 is 45°.

[0072] This embodiment is based on the device for predicting the chassis stone knocking sound in the vehicle. Figure 1 To better understand this embodiment, an actual embodiment is provided.

[0073] The collected stones 1 are placed in the hourglass 2, the hourglass 2 is fixed on the support 3, one end of the bottom guard plate 4 is in contact with the ground 6, the other end is supported by the telescopic rod 5, so that the bottom guard plate 4 forms an angle with the ground 6, the third microphone 7 is located on the side of the bottom guard plate 4 in contact with the ground 6, and the distance between the third microphone 7 and the knocking point 9 on the bottom guard plate 4 is 20cm, and the angle between the third microphone 7 and the knocking point 9 on the bottom guard plate 4 is 45°.

[0074] The hourglass 2 is located directly above the knocking point 9 on the bottom guard plate 4, and the bottom end of the hourglass 2 is away from the knocking point 9 on the bottom guard plate 4 by a distance.

[0075] In summary, the present application adjusts the height of the telescopic rod, collects the near-field noise of the stone hitting the bottom guard plate at multiple angles, combines the test results of the reference vehicle to develop the sound transmission function target of the vehicle, and finally plays the collected noise in the anechoic chamber-anechoic test room set, and adjusts the sound insulation of the test window until the sound transmission characteristics consistent with the target of the development vehicle are simulated, so that the stone hitting sound can be evaluated without the development vehicle test vehicle.

[0076] The above describes in detail the method and device for predicting the chassis stone hitting sound in the vehicle. The principles and implementation modes of the present application are described by using specific examples. The above examples are only used to help understand the method and core idea of the present application. Meanwhile, for those skilled in the art, the specific implementation modes and application ranges can be changed according to the idea of the present application. In summary, the content of the present application should not be understood as a limitation.

Claims

1. A method for predicting and evaluating the sound of stones striking the chassis inside a vehicle, characterized in that, Includes the following steps: Step S1: After adjusting the aperture of the hourglass (2) so that the stones (1) leak out at a uniform speed, turn on the third microphone (7) to collect the tapping sound of the stones (1) hitting the tapping point (9) on the bottom guard plate (4); Step S2: After changing the angle between the bottom guard plate (4) and the ground (6) by adjusting the length of the telescopic rod (5), repeat steps S1 to S2 to obtain multiple knocking sounds. Step S3: In the semi-anechoic chamber, the acoustic transmission function ATF1 of the target vehicle is determined based on the acoustic transmission function ATF1 measured by the benchmark vehicle. Step S4: The acoustic transmission function ATF2 of the vehicle to be developed is simulated using an anechoic chamber-anechoic test chamber set (12). A first sound source (15) is arranged in the first anechoic chamber, and a first microphone (16), a test window (13) and a sound insulation component (14) are arranged in the second anechoic chamber. The acoustic transmission function ATF3 between the first anechoic chamber and the second anechoic chamber is measured using the first sound source (15) and the first microphone (16). In step S5, after adjusting the positions of the sound insulation component (14), the first sound source (15) and the first microphone (16) respectively, the acoustic transmission function ATF3 between the first anechoic chamber and the second anechoic chamber is measured again using the first sound source (15) and the first microphone (16). It is then determined whether the acoustic transmission function ATF3 is similar to the acoustic transmission function ATF2 obtained in step S3. If so, step S6 is executed; otherwise, step S5 is executed. Step S6: After playing the multiple knocking sounds obtained in step S2 using the first sound source (15), the evaluator's ear is brought close to the first microphone (16) to make subjective scores and evaluations, and the average score is calculated. At the same time, the average score is compared and analyzed with the objective data. Step S7: After replacing the underbody protection plate (4), and repeating steps S1 to S7, the evaluation of the stone knocking sound of the chassis of the vehicle to be developed is completed.

2. The method for predicting and evaluating the sound of stones striking the chassis inside a vehicle according to claim 1, characterized in that, In step S2, the angle between the bottom protective plate (4) and the ground (6) includes 30°, 40°, 50°, 60°, 70° and 80°.

3. The method for predicting and evaluating the sound of stones striking the chassis inside a vehicle according to claim 1, characterized in that, In step S3, the calibration of the measured acoustic transfer function ATF1 specifically involves: A second microphone (10) is placed at a designated location on the benchmark vehicle, and a second sound source (11) is placed at the driver's left ear. The acoustic transmission function ATF1 between the designated location on the benchmark vehicle and the driver's left ear is measured.

4. The method for predicting and evaluating the sound of stones striking the chassis inside a vehicle according to claim 3, characterized in that, The designated position of the benchmark vehicle is located behind the left front wheel of the benchmark vehicle, and the vertical distance from the center of the front wheel is 1m to 1.5m. The second microphone (10) is 0.1m to 0.15m above the ground.

5. A device for detecting the sound of stones striking the chassis inside a vehicle, wherein the device employs the method for predicting and evaluating the sound of stones striking the chassis inside a vehicle as described in any one of claims 1-4, characterized in that... The device includes an hourglass (2), a bracket (3), a telescopic rod (5), a third microphone (7), and a tripod (8); The hourglass (2) is fixed on the bracket (3); The telescopic rod (5) supports one end of the bottom guard plate (4), so that the bottom guard plate (4) forms an angle with the ground (6); The hourglass (2) is located directly above the bottom guard plate (4), and the bottom end of the hourglass (2) is a distance away from the striking point (9) on the bottom guard plate (4); The third microphone (7) is fixed on the tripod (8); The line connecting the third microphone (7) and the striking point (9) on the bottom guard plate (4) forms a distance, and it forms an angle with the bottom guard plate (4).

6. The chassis stone-tapping sound device inside a vehicle according to claim 5, characterized in that, The bottom of the hourglass (2) and the striking point (9) on the bottom guard plate (4) form a distance of 1.5m to 1.6m.

7. A chassis stone-tapping sound device for a vehicle interior according to claim 5, characterized in that, The line connecting the third microphone (7) and the striking point (9) on the bottom guard plate (4) forms a distance of 20cm to 20.5cm.

8. A chassis stone-tapping sound device for a vehicle as described in claim 5, characterized in that, The angle between the third microphone (7) and the bottom protective plate (4) is 45°.

9. An electronic device, characterized in that, It includes a processor, a communication interface, a memory, and a communication bus, wherein the processor, the communication interface, and the memory communicate with each other through the communication bus; Memory, used to store computer programs; A processor, when executing a program stored in memory, implements the steps of the method described in any one of claims 1-8.

10. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores a computer program that, when executed by a processor, implements the steps of the method described in any one of claims 1-8.

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