Method and device for measuring vehicle vibration noise characteristic data and medium

Abstract

The invention discloses a method and a device for measuring vehicle vibration noise characteristic data, and a medium. The method comprises the following steps: controlling a target vehicle to run at a constant speed on a test road surface to pass through a first reflector; according to the prompt tone triggered by the first reflector, the target vehicle is controlled to run in an accelerated mode to pass through the second reflector; according to the prompt tone triggered by the second reflector, the target vehicle is controlled to run through a third reflector according to the preset vehicle speed; controlling the target vehicle to stop accelerating according to the prompt tone triggered by the third reflector; on-vehicle wired signals and ground wireless signals of the target vehicle during testing are synchronously collected, and vehicle vibration noise characteristic data of the target vehicle are obtained. According to the method and device for measuring the vibration noise characteristic data of the vehicle and the medium, effective information of the target vehicle in the testing process can be obtained by means of accurately controlling acceleration, deceleration and the like, and the problem that the accuracy of measuring the vibration noise characteristic data of the vehicle is difficult to improve through a simple and convenient method can be solved.

Description

Technical Field

[0001] The present invention relates to the field of vehicle technology, and in particular to a method, device and medium for measuring vehicle vibration and noise characteristic data. Background Art

[0002] At present, all regions have regulations on vehicle noise measurement methods and limits, requiring the use of specific methods and equipment to collect noise and related parameters under certain environmental conditions and vehicle driving conditions to evaluate whether the vehicle noise is compliant. During the development process, automobile manufacturers need to measure vehicle vibration and noise parameters according to regulations so that they can conduct diagnostic analysis and determine the cause of the failure when the vehicle does not meet the standards. Traditionally, the measurement of vehicle vibration and noise characteristic data mainly adopts the sound level meter measurement method. Through the calibrated sound level meter, at the preset test location and sampling point, the range and mode are set according to the measurement requirements to capture steady-state, periodic and irregular noise data; the A sound level is read using the fast or slow gear, the sampling information is recorded, and the equivalent continuous sound level and other analyses are performed to obtain relevant data; or by integrating the in-vehicle and out-vehicle equipment collectors, and wirelessly transmitting data such as vehicle speed, engine speed and sound pressure level to the host computer for display on the display and control device, and using a micro printer to print relevant data; and through two independent data acquisition systems, VBOX and sound level meter, respectively collect vehicle data such as engine speed, GPS signal and reflector position and noise signals at a certain point outside the vehicle, and store them in their respective systems.

[0003] However, in the traditional measurement method, the measurement efficiency is low due to the large number of components; and the position of the reflector is fixed, which makes it difficult to flexibly adjust according to various standards and test items, making it difficult to meet the diverse needs of different regulations; at the same time, this method cannot accurately prompt the driver to press and release the accelerator pedal. The specific time and position, resulting in low measurement accuracy. Summary of the invention

[0004] The present invention provides a method, device and medium for measuring vehicle vibration and noise characteristic data, so as to solve the problem that it is difficult to improve the accuracy of measuring vehicle vibration and noise characteristic data by a simple method.

[0005] Controlling the target vehicle to travel at a constant speed on a test road surface passing by a first reflector; wherein the test road surface is provided with a plurality of reflectors distributed along the center line of the road surface;

[0006] According to the prompt sound triggered by the first reflector, the target vehicle is controlled to accelerate and drive past the second reflector;

[0007] According to the prompt sound triggered by the second reflector, the target vehicle is controlled to drive past the third reflector at a preset speed;

[0008] According to the prompt sound triggered by the third reflector, controlling the target vehicle to stop accelerating;

[0009] The vehicle vibration and noise characteristic data of the target vehicle are obtained by synchronously collecting the on-vehicle wired signal and the ground wireless signal of the target vehicle when the target vehicle is tested on the test road surface according to the data collector placed in the target vehicle.

[0010] The present invention sets clear test steps, including driving at a constant speed, accelerating, driving at a preset speed, and stopping acceleration. These standardized test processes help ensure the consistency of each test, thereby facilitating comparison and analysis of different test data. Among them, by accurately controlling the driving path and speed of the target vehicle on the test road surface, the operational complexity and time consumption caused by the numerous components in the traditional measurement method are reduced. The combination of the reflector and the prompt sound makes the test process more concise and clear, thereby improving the measurement efficiency. In addition, the driving state of the vehicle is controlled according to the prompt sound triggered by the reflector, which can achieve flexible adjustment under different test requirements and regulatory requirements. This flexibility allows the method to adapt to a variety of standards and test items. In addition, through the prompt sound triggered by the reflector, the driver can accurately know when to step on and release the accelerator pedal. This precise control reduces the error caused by improper operation of the driver and helps to improve the accuracy of the measurement data.

[0011] Compared with the prior art, the present invention can obtain effective information of the target vehicle during the test process by simplifying the test process and accurately controlling acceleration and deceleration, thereby solving the problem of difficulty in improving the accuracy of measuring vehicle vibration and noise characteristic data through simple methods.

[0012] As a preferred solution, the target vehicle is controlled to travel at a constant speed on the test road surface past the first reflector, specifically:

[0013] Installing a photoelectric sensor at a preset reference point of the target vehicle;

[0014] Adjusting the plurality of reflective plates so that the photoelectric sensor can trigger sensing according to the reflected light of the plurality of reflective plates to output a high level;

[0015] On the test road surface, the target vehicle is controlled to travel at a constant speed according to a preset speed until it passes the first reflector.

[0016] In this preferred solution, the position of the reflector can be set according to the needs, so that the test process becomes relatively simple. The driver only needs to drive at a constant speed according to the preset speed without any additional operation or judgment. Based on the precise coordination of the photoelectric sensor and the reflector, and the control of the vehicle's constant speed, the accuracy of the test results can be significantly improved.

[0017] As a preferred solution, according to the prompt sound triggered by the first reflector, the target vehicle is controlled to accelerate and drive past the second reflector, specifically:

[0018] When the reference point of the target vehicle passes through the first reflector, according to the prompt sound triggered by the first reflector, the target vehicle is controlled to accelerate and pass through the second reflector;

[0019] The prompt sound is obtained when the photoelectric sensor outputs a high-level signal according to the reflected light received from the first reflector, and triggers the prompt sound module of the target vehicle to play the prompt sound based on the output duration of the high-level signal.

[0020] In this preferred solution, the playing of the prompt tone provides intuitive feedback to the driver, indicating that the vehicle has reached the preset trigger point. This feedback method helps the driver to maintain attention during the test and make timely responses as needed. Since non-contact photoelectric sensors and reflectors are used during the test, safety risks caused by direct contact with the vehicle or road are avoided.

[0021] As a preferred solution, according to the prompt sound triggered by the third reflector, the target vehicle is controlled to stop accelerating, specifically:

[0022] If the reference point is at the rear end of the target vehicle, when the reference point of the target vehicle passes the second to last reflector of the plurality of reflectors, the target vehicle is controlled to stop accelerating according to a prompt sound triggered by the second to last reflector;

[0023] If the reference point is not at the rear end of the target vehicle, when the reference point of the target vehicle passes the last reflector of the plurality of reflectors, the target vehicle is controlled to stop accelerating according to a prompt sound triggered by the last reflector.

[0024] This preferred solution takes into account the fact that the reference point may be located at different positions of the vehicle (rear end, front end or middle part), and designs different trigger points accordingly. This design enables the test method to be flexibly applied to various vehicle models without making major adjustments due to different vehicle configurations.

[0025] As a preferred solution, the test road surface is provided with a number of reflectors distributed along the center line of the road surface, specifically:

[0026] Five reflectors are arranged at the center line of the test road surface along the direction of vehicle travel;

[0027] Among them, the placement positions of the five reflectors are symmetrical about the test section of the test road surface. If the target vehicle needs to perform an entry-line test from both ends of the test section, an auxiliary reflector is added behind the second reflector at the preset end of the test section to identify the driving direction of the target vehicle.

[0028] In this preferred solution, the symmetrical arrangement of the five reflectors can ensure that the vehicle's driving trajectory on the test section is accurately recorded, and the symmetrically arranged reflectors can reduce the complexity of the test process. In addition, the setting of the auxiliary reflectors enables the test system to adapt to different test requirements. When the target vehicle needs to be tested from both ends of the test section, the auxiliary reflectors can clearly identify the vehicle's driving direction without large-scale adjustment or resetting of the test equipment.

[0029] As a preferred solution, the on-vehicle wired signal and the ground wireless signal include a sound pressure simulation signal, and the sound pressure simulation signal is collected based on a number of noise measurement points, specifically:

[0030] Arranging the plurality of noise measuring points on the test road surface; wherein the plurality of noise measuring points include vehicle exterior passing noise measuring points or vehicle exterior pedestrian warning sound measuring points arranged according to different test regulations;

[0031] A weak sound pressure signal collected by the microphone is amplified by a preamplifier, the amplified signal is conditioned into a standard analog signal by a signal conditioning device, and the conditioned standard analog signal is transmitted to a signal transmitting device; wherein the weak sound pressure signal is a sound pressure signal measured when the target vehicle passes through the plurality of noise measuring points when being tested on the test road surface;

[0032] After the signal transmitting device converts the standard analog signal into a modulated signal suitable for wireless transmission, the signal is sent to a signal receiving device for demodulation, and the sound pressure analog signal obtained after signal demodulation is collected by the data collector;

[0033] Each group of signal transmitting devices and signal receiving devices is provided with a different carrier frequency.

[0034] This preferred solution arranges multiple noise measurement points on the test road surface, and can flexibly choose to arrange external vehicle passing noise measurement points or external vehicle pedestrian warning sound measurement points according to different test regulations to meet different test needs. A preamplifier is used to amplify the weak sound pressure signal collected by the microphone, and the amplified signal is conditioned into a standard analog signal through a signal conditioning device, which improves the stability and accuracy of the signal and is beneficial to subsequent fault diagnosis and analysis. The standard analog signal is converted into a modulated signal suitable for wireless transmission through a signal transmitting device, and sent to a signal receiving device for demodulation, thereby realizing wireless transmission of the signal and avoiding the wiring complexity and limitations that may be caused by wired transmission. In addition, each group of signal transmitting devices and signal receiving devices is provided with different carrier frequencies, which can effectively avoid signal interference between different measuring points and ensure accurate transmission and reception of data.

[0035] As a preferred solution, after obtaining the vehicle vibration and noise characteristic data of the target vehicle, the method further includes:

[0036] Performing spectrum analysis on the ground wireless signal to obtain spectrum analysis results;

[0037] Fault diagnosis is performed on the target vehicle according to the spectrum analysis result.

[0038] In this preferred solution, spectrum analysis can quickly capture abnormal characteristics of signals, such as frequency offset, signal attenuation, etc., thereby shortening the time for fault diagnosis and improving diagnostic efficiency, so that faults or abnormalities in the target vehicle can be accurately located.

[0039] The present application also provides a device for measuring vehicle vibration and noise characteristic data, including a constant speed module, an acceleration module, a control module, a release module and a processing module;

[0040] The constant speed module is used to control the target vehicle to travel at a constant speed on the test road surface and pass the first reflector; wherein the test road surface is provided with a plurality of reflectors distributed along the center line of the road surface;

[0041] The acceleration module is used to control the target vehicle to accelerate and drive past the second reflector according to the prompt sound triggered by the first reflector;

[0042] The control module is used to control the target vehicle to drive past the third reflector at a preset speed according to the prompt sound triggered by the second reflector;

[0043] The release module is used to control the target vehicle to stop accelerating according to the prompt sound triggered by the third reflector;

[0044] The processing module is used to synchronously collect the on-vehicle wired signals and the ground wireless signals of the target vehicle when the target vehicle is tested on the test road surface according to the data collector placed in the target vehicle, so as to obtain the vehicle vibration and noise characteristic data of the target vehicle.

[0045] As a preferred solution, the constant speed module includes a mounting unit, an adjustment unit and a constant speed unit;

[0046] Wherein, the installation unit is used to install a photoelectric sensor at a preset reference point of the target vehicle;

[0047] The adjustment unit is used to adjust the plurality of reflective plates so that the photoelectric sensor can trigger sensing according to the reflected light of the plurality of reflective plates to output a high level;

[0048] The constant speed unit is used to control the target vehicle to travel at a constant speed at a preset speed on the test road surface until it passes the first reflector.

[0049] As a preferred solution, the acceleration module includes an acceleration unit;

[0050] Wherein, the acceleration unit is used to control the target vehicle to accelerate and pass through the second reflector according to the prompt sound triggered by the first reflector when the reference point of the target vehicle passes through the first reflector;

[0051] The prompt sound is obtained when the photoelectric sensor outputs a high-level signal according to the reflected light received from the first reflector, and triggers the prompt sound module of the target vehicle to play the prompt sound based on the output duration of the high-level signal.

[0052] As a preferred solution, the release module tail unit and trigger unit;

[0053] Wherein, the tail end unit is used to control the target vehicle to stop accelerating according to the prompt sound triggered by the penultimate reflector when the reference point of the target vehicle passes through the penultimate reflector of the plurality of reflectors if the reference point is at the tail end of the target vehicle;

[0054] The trigger unit is used to control the target vehicle to stop accelerating according to the prompt sound triggered by the last-to-last reflector when the reference point of the target vehicle passes through the last-to-last reflector of the plurality of reflectors if the reference point is not at the rear end of the target vehicle.

[0055] As a preferred solution, the test road surface is provided with a number of reflectors distributed along the center line of the road surface, specifically:

[0056] Five reflectors are arranged at the center line of the test road surface along the direction of vehicle travel;

[0057] Among them, the placement positions of the five reflectors are symmetrical about the test section of the test road surface. If the target vehicle needs to perform an entry-line test from both ends of the test section, an auxiliary reflector is added behind the second reflector at the preset end of the test section to identify the driving direction of the target vehicle.

[0058] As a preferred solution, the on-vehicle wired signal and the ground wireless signal include a sound pressure simulation signal, and the sound pressure simulation signal is collected based on a number of noise measurement points, specifically:

[0059] Arranging the plurality of noise measuring points on the test road surface; wherein the plurality of noise measuring points include an external vehicle passing noise measuring point or an external vehicle pedestrian warning sound measuring point;

[0060] A weak sound pressure signal collected by the microphone is amplified by a preamplifier, the amplified signal is conditioned into a standard analog signal by a signal conditioning device, and the conditioned standard analog signal is transmitted to a signal transmitting device; wherein the weak sound pressure signal is a sound pressure signal measured when the target vehicle passes through the plurality of noise measuring points when being tested on the test road surface;

[0061] After the signal transmitting device converts the standard analog signal into a modulated signal suitable for wireless transmission, the signal is sent to a signal receiving device for demodulation, and the sound pressure analog signal obtained after signal demodulation is collected by the data collector;

[0062] Each group of signal transmitting devices and signal receiving devices is provided with a different carrier frequency.

[0063] As a preferred solution, after obtaining the vehicle vibration and noise characteristic data of the target vehicle, the method further includes:

[0064] Performing spectrum analysis on the ground wireless signal to obtain spectrum analysis results;

[0065] Fault diagnosis is performed on the target vehicle according to the spectrum analysis result.

[0066] The present application also provides a storage medium, on which a computer program is stored. The computer program is called and executed by a computer to implement the method for measuring vehicle vibration and noise characteristic data as described above. BRIEF DESCRIPTION OF THE DRAWINGS

[0067] Figure 1 It is a flow chart of a method for measuring vehicle vibration and noise characteristic data provided by an embodiment of the present application;

[0068] Figure 2 It is a schematic diagram of the first structural composition provided in an embodiment of the present application;

[0069] Figure 3 It is a schematic diagram of the second structural composition provided in an embodiment of the present application;

[0070] Figure 4 It is a schematic diagram of the arrangement position of the noise test reflector provided in the embodiment of the present application;

[0071] Figure 5 This is a schematic diagram of test data of accelerating through a measurement site according to GB1495-2002 provided in an embodiment of the present application;

[0072] Figure 6 This is a table showing the test data of the ECE R51.03 acceleration through the measurement site provided in the embodiment of the present application;

[0073] Figure 7 is a spectrum diagram of the in-vehicle sound pressure level and the outside-vehicle sound pressure level of the curve data provided in the embodiment of the present application;

[0074] Figure 8 This is a comparison diagram of wireless signal and wired signal delays in different solutions provided in the embodiments of the present application;

[0075] Fig. 9 This is a comparison diagram of the spectrum of wireless signals and wired signals in different solutions provided in the embodiments of the present application;

[0076] Fig.10 It is a structural schematic diagram of a device for measuring vehicle vibration and noise characteristic data provided by an embodiment of the present application. DETAILED DESCRIPTION

[0077] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0078] In the description of the present application, it should be understood that the terms "first", "second" and "third" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first", "second" and "third" may explicitly or implicitly include one or more of the features. In the description of the present application, unless otherwise specified, "several" means two or more.

[0079] A method for measuring vehicle vibration and noise characteristic data provided in an embodiment of the present application is mainly used in situations where it is necessary to record vehicle dynamic performance data simultaneously through a simple and adaptable method to improve the accuracy of measuring vehicle vibration and noise characteristic data.

[0080] Embodiment 1:

[0081] See also Figure 1 The embodiment of the present application provides a method for measuring vehicle vibration and noise characteristic data, including S1 to S5, and the specific implementation steps are as follows:

[0082] S1. Control the target vehicle to travel at a constant speed on a test road surface and pass by a first reflector; wherein the test road surface is provided with a plurality of reflectors distributed along the center line of the road surface.

[0083] Step S1 of the embodiment of the present application includes S1.1 to S1.9, wherein S1.1 is a process of setting up the first integrated measurement system, S1.2 is a process of setting up the device required for the test, S1.3 is a process of setting up the reflector, S1.4 is a process of initializing and calibrating the device, S1.5 is a process of starting and calibrating the device, S1.6 is a process of data calibration, S1.7 is a process of initializing the vehicle, S1.8 is a process of performing a pre-test, and S1.9 is a process of performing a formal test, specifically:

[0084] S1.1. Set up a first integrated measurement system, and install the photoelectric sensor and other related equipment in the first integrated measurement system at a preset reference point of the target vehicle; wherein the position of the reference point is determined according to the installation position of the powertrain, that is, the installation position of the powertrain is the reference point;

[0085] In addition, the first integrated measurement system is composed of a data collector 1-1 (universal multi-channel data collector), a bus signal acquisition module 2, a satellite navigation system module 3, a GPS antenna 4, an acceleration sensor 5, a microphone (including a preamplifier) ​​6, a photoelectric sensor 7, a reflector 8, a prompt sound module 9-1, an earphone 10, a portable computer and data acquisition and analysis, control and display software 11, a signal conditioning device 12, a signal transmitting device 13, a signal receiving device 14 and other partial structures; specifically:

[0086] ① Data collector 1-1: A general-purpose multi-channel data collector is used, with a built-in lithium battery and external DC power supply, equipped with at least 4 analog input channels, capable of achieving a full-channel parallel sampling rate of more than 50kHz, and an analog-to-digital resolution between 16 and 24 bits. In addition, the maximum range of the analog input channel exceeds 10V, and each channel is provided with at least 3 ranges that can be programmably adjusted. The data acquisition accuracy is higher than one thousandth of the full range, and the background noise of each channel can be ensured to be less than 50μV RMS. Its embodiments include Siemens SCADAS MOBILE series, Hyde headlab series data acquisition front ends, or other general data acquisition front ends that meet the requirements.

[0087] ②Bus signal acquisition module 2: It can exist as an independent unit or be integrated into the data collector 1-1. It can decode the vehicle accelerator pedal opening, vehicle speed, motor speed, engine speed and other signals in real time according to the imported vehicle model DBC file, and it is also compatible with the bus system in CAN / CAN FD data format for communication.

[0088] ③ Satellite navigation system module 3: It can be used as an independent component or integrated into the data collector 1-1, and at least includes a module that can communicate with satellite positioning systems such as GPS / Beidou / GLONASS to calculate information such as vehicle speed and vehicle position.

[0089] ④GPS antenna 4: It is a universal type, equipped with a preamplifier and a magnetic mount, which is easy to be adsorbed on the outside of the vehicle body. Its cable length is not less than 2 meters, and the interface must match the satellite navigation system module 3. The satellite navigation system module 3 and GPS antenna 4 adopt a redundant design, which is intended to be used as a backup solution when the vehicle bus network cannot obtain the bus signal.

[0090] ⑤ Accelerometer 5: It adopts ICP / IEPE ceramic or quartz piezoelectric shear type design, with a power supply voltage of 24V, a flat frequency response range of more than 2Hz to 5000Hz, and an applicable temperature range of more than 0℃ to 120℃. Its sensitivity range (deviation 5%) is between 40mv / g and 100mv / g, the lateral sensitivity does not exceed 5%, and the amplitude nonlinearity is not more than 1%.

[0091] ⑥ Microphone (including preamplifier) ​​6: 1 / 2 inch free-field microphone, in line with IEC61672 Class 1 accuracy, dynamic range greater than 20dBA ~ 120dBA, flat frequency response range greater than: 20Hz ~ 20kHz, sensitivity 50mv / pa.

[0092] ⑦ Photoelectric sensor 7: It adopts diffuse reflection design, can be 3-wire or 4-wire PNP normally open type, the power supply voltage range is between 10V and 30V, the detection distance can be adjusted within 500mm to 1000mm, and the photoelectric sensor can be arranged according to different regulatory requirements. In addition, the sensor can also use other types of photoelectric detection high-level output switch sensors, such as photoelectric sensors for detecting displacement differences.

[0093] ⑧Reflector 8: It can be made of metal or non-metal material, and its shape is a rectangular cross-section thin-walled structure with a width between 20mm and 100mm and a height between 10mm and 50mm. The length can be selected within the range of 500mm to 1000mm. The surface of the reflector should be white or other light colors that form a significant color difference with the road surface. Alternatively, the paint marking line can be directly sprayed on the road surface. The number of reflectors matches the model parameters of the photoelectric sensor 7, and does not exceed 6 pieces.

[0094] ⑨ Prompt sound module 9-1: It has the function of storing audio files and supports the input of edited prompt sound files. The prompt sound file is a sine wave MP3 format audio file with a duration of 50ms and a frequency of 5000Hz. The trigger input voltage range is between 5V and 24V, and the broadcast delay after triggering is less than 10ms. The trigger mechanism uses a comparator to detect the high-level signal output by the photoelectric sensor. The reference voltage is set to 3V. Once the input voltage exceeds this threshold, the comparator outputs a high-level trigger signal. In view of the short duration of the trigger signal (10ms to 15ms), a delay circuit is specially designed to ensure that the signal is reliably captured. A 555 timer is used to achieve delay and signal shaping. The delay is slightly longer than the longest trigger signal duration to ensure that the signal is fully captured;

[0095] In addition, the microcontroller unit (MCU) selected must have audio decoding and output capabilities, such as the STM32 series or ESP32 series, etc., configured to read the audio file from the memory after receiving the trigger signal, and play it through the audio output pin. The audio output circuit connects the MCU audio output pin to the audio amplifier circuit, using a low-power audio amplifier integrated circuit (such as LM386) or an advanced amplifier module that adapts to the 5V to 15V input voltage range. To provide a stable voltage for the MCU and amplifier circuit, a wide voltage range regulator (such as LM7805, LM1117, etc.) is used for voltage conversion, or a switching regulator (such as LM2576, LM2596, etc.) is selected to replace the linear regulator for power consumption and efficiency considerations.

[0096] ⑩ Earphone 10: uses universal 3.5mm three-section stereo connector.

[0097] Portable computer and data acquisition and analysis, control and display software 11: The hardware configuration requirements include: main frequency exceeding 2GHz, RAM capacity exceeding 8GB, ROM capacity exceeding 500GB, and display screen size not less than 15.6 inches. The software part must be aretemis version 10.5 or above, or testlab version 19 and above.

[0098] Signal conditioning device 12: This device mainly provides 2mA constant current power supply for IEPE microphone (including preamplifier) ​​6, which is used to collect the sound pressure signal outside the vehicle and convert it into a standard 0V to 5V AC voltage signal. The background noise of this device is less than 0.5μV, and one specific model is 61000.

[0099] Signal transmitting device 13 and signal receiving device 14: One of the embodiments is WAS-101, and its carrier frequency range is set between 570MHz and 600MHz. After the sound pressure signal is sampled and encoded, it is loaded onto the carrier and output by digital modulation. The output gain is adjustable, and 15 sets of adjustable carrier frequencies are provided. The working principle of the wireless transmission system is summarized as follows: the sound pressure signal of the noise outside the vehicle or the pedestrian warning sound measurement point is collected by the microphone, amplified by the preamplifier, and converted into a standard analog signal by the signal conditioning device. The signal is transmitted to the signal transmitting device via a wired manner, and the latter modulates the sound pressure signal. The modulated signal is amplified and emitted by the antenna in the form of UHF frequency band electromagnetic waves. After the antenna of the signal receiving device receives the transmitted carrier signal, it performs a demodulation operation to restore the original sound pressure analog signal, and then sends it to the analog signal acquisition channel of the data collector via a wired connection. When multiple sound pressure signal measurement points are set outside the vehicle, each group of signal transmitting and receiving devices (corresponding to each channel) can be configured with a different carrier frequency to ensure that there is no frequency interference between the signals of each channel;

[0100] Furthermore, the signal transmitting device 13, the signal conditioning device 12 and the external microphone (including the preamplifier) ​​6 are arranged on a tripod on the PP' line, and the signal receiving device 14 is arranged outside the vehicle body and fixed by a magnetic base or other fixing methods.

[0101] To apply the embodiments of this application, please refer to Figure 2 , Figure 2 It is a schematic diagram of the first structural composition provided in an embodiment of the present application, which shows the specific structure of the first comprehensive measurement system.

[0102] To apply the embodiments of this application, please refer to Figure 3 , Figure 3is a schematic diagram of a second structural composition provided in an embodiment of the present application, showing the specific structure of another integrated measurement system (second integrated measurement system) provided in this embodiment;

[0103] Moreover, the difference between the second integrated measurement system and the first system is mainly reflected in the data collector 1-2. The collector of the second integrated measurement system is a portable integrated type, integrating data collection, control and display functions, equipped with an embedded operating system and storage device, supporting data collection and analysis processing in stand-alone mode, and can also be connected to a computer and its supporting host computer software for data operation. This design allows a single driver to complete vehicle driving and data collector operations. For example, Hyde's SQIII data collector can be used, which supports blind operation mode and can display data such as vehicle speed in real time. Combined with the prompt sound module 9-1 (which can be replaced in this embodiment) or the light emitter 9-2, the driver can adjust the vehicle operation accordingly to ensure that the vehicle operating parameters meet regulatory standards. During data collection, post-processing such as Siemens testlab software is still used to obtain operating data such as vehicle acceleration;

[0104] also, Figure 3 Compared to Figure 2 Another significant change of the system shown is that the prompt sound module 9-1 and the earphone 10 are cancelled, and the light emitter 9-2 is used instead. The light emitter is placed on the vehicle instrument display screen (or near the position where the data collector or acquisition software displays the vehicle speed), and the driver controls the vehicle by observing the vehicle speed corresponding to the light emission moment to meet the specified operating requirements.

[0105] It should be noted that the measurement of the vehicle vibration and noise characteristic data in this embodiment is completed based on the integrated measurement system (the first integrated measurement system or the second integrated measurement system) provided in this embodiment.

[0106] S1.2. Ensure that components 1-2 to 14 in the first integrated measurement system are correctly connected, and then turn on the power switch of the data collector. Next, properly store the DBC file for the vehicle to be tested in the memory card of the collector. At this time, the required channels need to be opened, including analog channels, CAN channels, and GPS channels.

[0107] When configuring the data logger parameters, key information such as channel name, coupling mode, and sensitivity of the input accelerometer should be specified. In particular, for wired accelerometers and in-vehicle microphones, the coupling mode should be ICP / IEPE; the coupling mode of photoelectric sensors is DC; and for wireless transmission of out-vehicle microphones, the coupling mode is AC.

[0108] In addition, the data interaction mode, data frame format, sampling point location, baud rate and other parameters of the CAN channel need to be set according to the actual situation of the vehicle CAN data type. At the same time, in order to meet the needs of online monitoring and viewing, the CAN channel data to be displayed also needs to be set, which includes but is not limited to key indicators such as accelerator pedal opening, vehicle speed, motor speed and engine speed.

[0109] S1.3. Arrange five reflectors (i.e., reflectors 8 of the first integrated measurement system) along the vehicle's travel direction at the center line of the test road surface, namely, reflector 8-1, reflector 8-2, reflector 8-3, reflector 8-4, and reflector 8-5; and the number and placement of these reflectors can be adjusted as required;

[0110] Adjust several reflective plates so that the photoelectric sensor can trigger induction according to the reflected light of several reflective plates to output a high level;

[0111] The placement positions of the five reflectors are symmetrical about the test section of the test road. If the target vehicle needs to be tested from both ends of the test section, an auxiliary reflector (reflector 8-6) is added after the second reflector at the preset end of the test section.

[0112] By setting the width of the auxiliary reflector to be smaller than a preset value, when the reference point of the target vehicle passes through the auxiliary reflector (reflector 8-6), the duration of the high-level signal output by the photoelectric sensor is shorter than the trigger threshold required by the prompt sound module (9-1), thereby not triggering the prompt sound module to play the prompt sound.

[0113] To apply the embodiments of this application, please refer to Figure 4 , Figure 4 This is a schematic diagram of the arrangement of the reflective plate for the noise test provided in the embodiment of the present application. Figure 4 The installation method of the reflector is described in detail:

[0114] When conducting a vehicle pass-by noise test in accordance with GB1495 or ECE R51 standards, several reflectors must be precisely arranged along the CC' centerline of the vehicle's travel direction. Different reflectors can be set according to the position of the reference points to ensure the accuracy and effectiveness of the test. The following is an explanation using five reflectors as an example:

[0115] The first reflector 8-1 should be placed before the AA' line, and its distance from the AA' line is equal to the vehicle length minus the distance from the reference point to the front end of the vehicle. If the reference point of the target vehicle is located at the front or rear end of the vehicle, the distance between the reflector and the AA' line is the vehicle length;

[0116] The second reflector 8-2: needs to be precisely positioned on the AA' line as a key reference;

[0117] The third reflector 8-3: should be placed on the PP' line as an important reference point during the vehicle's movement;

[0118] The fourth reflector 8-4: needs to be set on the BB' line to further monitor the noise performance of the vehicle;

[0119] The fifth reflector 8-5 should be placed after the BB' line, and its distance from the BB' line should be equal to the distance between the first reflector 8-1 and the AA' line to ensure the symmetry and consistency of the test;

[0120] In addition, the five reflectors need to be arranged symmetrically about the PP' line. If the test requires the vehicle to enter the line from two directions for testing, an additional reflector 8-6 needs to be added between AA' and PP' or between PP' and BB' to accurately determine the driving direction of the vehicle.

[0121] In addition, when conducting the ECE R51 vehicle noise test, the arrangement of the reflectors is also adjusted according to the different requirements of Method A and Method B to ensure the accuracy and effectiveness of the test:

[0122] ① If the test is conducted in accordance with ECE R51 Method A, it is necessary to ensure that the vehicle travels at a stable acceleration between the AA' and BB' lines. The specific requirements are: when the reference point reaches the AA' line, the vehicle speed should be accurately controlled within the range of 50km / h±1km / h; and when the rear end of the vehicle exits the BB' line, the driver should release the accelerator pedal. In this case, in order to simplify the test process, it is only necessary to arrange reflectors 8-1 (located before the AA' line, used to control vehicle acceleration), 8-2 (located on the AA' line, as a reference point for the vehicle traveling at a stable acceleration), 8-4 (located on the BB' line, used to control the vehicle to stop accelerating when the rear end of the vehicle passes this position) and 8-5 (located after the BB' line, for vehicles whose reference point is not at the rear end of the vehicle, used to determine that the vehicle stops accelerating when the rear end of the vehicle passes this position).

[0123] ② If the test is conducted in accordance with ECE R51 Method B, the vehicle is also required to maintain a stable acceleration between the AA' and BB' lines. However, the difference is that it is necessary to ensure that the vehicle speed reaches 50km / h±1km / h when the reference point reaches the PP' line, and the accelerator pedal is released when the rear end of the vehicle passes the BB' line. In addition, if the reference point is not located at the rear end of the vehicle, in order to optimize the test layout, it is only necessary to arrange reflectors 8-1 (also located before the AA' line), 8-3 (located on the PP' line, as a key reference point for accelerating to the target speed) and 8-5 (located after the BB' line, used to determine that the vehicle stops accelerating when the rear end of the vehicle passes this position).

[0124] It should be noted that in the vehicle noise test of the ECE R51 standard, Method A and Method B are two different test schemes; Method A requires the vehicle to travel at a steady acceleration in the test area from line AA' to line BB', and the reference point must reach the target speed range when it reaches line AA'; Method B also requires the vehicle to travel at a steady acceleration in the test area, but this time the reference point must reach the target speed range when it reaches line PP'.

[0125] In this embodiment S1.3, the position of the reflector can be set according to the needs, so that the test process becomes relatively simple. The driver only needs to drive at a constant speed according to the preset speed without any additional operation or judgment. Based on the precise coordination of the photoelectric sensor and the reflector, and the control of the vehicle's constant speed, the accuracy of the test results can be significantly improved;

[0126] Moreover, the symmetrical arrangement of the five reflectors ensures that the vehicle's driving trajectory on the test section is accurately recorded, and the symmetrical arrangement of the reflectors can reduce the complexity of the test process. In addition, the setting of the auxiliary reflectors enables the test system to adapt to different test requirements. When the target vehicle needs to be tested from both ends of the test section, the auxiliary reflectors can clearly identify the vehicle's driving direction without large-scale adjustment or resetting of the test equipment;

[0127] By setting up auxiliary reflectors and controlling their width, the output of the photoelectric sensor can be precisely controlled. When a vehicle passes by the auxiliary reflector, only a high-level signal is generated without triggering a prompt tone, which helps reduce interference and noise during the test and makes the test process smoother. In addition, it allows in-line testing from both ends of the test section without changing the overall layout of the test equipment or reconfiguring the test parameters. This method increases the flexibility of the test and enables it to adapt to different test needs and scenarios.

[0128] Compared with the present application, the prior art only has partial reflectors, such as reflectors 8-2, 8-4, and 8-6, wherein reflector 8-6 is used to determine the direction of the vehicle. The program sets that the driver will step on the accelerator pedal only after hearing the prompt sound when the vehicle enters AA', which does not meet the pre-acceleration requirements of the ECE R51.03 regulations. There is no prompt sound when passing the center PP', which is not convenient for the driver to control the vehicle to pass the PP' line speed of 50km / h±1km / h according to the ECE R51.03 requirements. When the rear end of the vehicle exits the BB' line, a long prompt sound is still used to prompt the driver to stop accelerating through the BB' line through the reference point, and the reference points of the front and mid-mounted engines are not at the rear end of the vehicle, which will cause different drivers to react at different speeds after hearing the long prompt sound, and release the accelerator pedal at different prompt sound moments, resulting in the actual stop acceleration position being the rear end of the vehicle in front of or behind the BB' line, which may cause a large test error and does not meet regulatory requirements.

[0129] In this embodiment S1.1 to S1.3, a single data collector is innovatively used. When placed in the vehicle, it can simultaneously obtain comprehensive data from vehicle sensors and ground sensors, covering diversified information such as acceleration, sound pressure, GPS signals, CAN bus signals, and photoelectric sensor signals. The layout of the ground sound pressure measurement points is flexible and can be flexibly adjusted according to different test regulations. At the same time, the layout of the reflector also complies with the test standards and project requirements, and accurately calibrates the position of the vehicle relative to the test site;

[0130] This solution is widely used in pedestrian warning sound testing, pass-by noise assessment and other scenarios that require synchronous monitoring of data inside and outside the vehicle. The in-vehicle warning sound is triggered by a dedicated module and a high-level linkage with the photoelectric sensor, and is directly transmitted to the driver in the form of headphones. It is completely independent of the data acquisition system and its software, ensuring that the in-vehicle noise measurement is not interfered with, and achieving harmonious coexistence of the warning sound and the in-vehicle noise;

[0131] The data collector of this solution has excellent performance, with a sampling rate of 100kHz and an analog-to-digital resolution of 24 bits, showing the dual advantages of high precision and high anti-interference ability. The signal transceiver device shows strong signal transmission capability, covering a wide range of 50 meters, with a flat frequency response range from 30Hz to 17kHz and a delay of less than 3 milliseconds, ensuring the efficiency and accuracy of wireless transmission and collection of external noise, and providing a solid data foundation for spectrum analysis and fault diagnosis.

[0132] S1.4. Initialize and calibrate the signal transmitter, signal receiver, and signal conditioner on the left side of the target vehicle according to the following steps:

[0133] First, turn on the power switches of the signal transmitter, signal receiver and signal conditioner on the left side outside the vehicle to ensure that all devices are in working condition.

[0134] Next, adjust the gain of the signal receiving device to the third level to ensure that the received signal strength is moderate for subsequent processing and analysis.

[0135] After confirming that the signal transmitting and receiving devices have been successfully connected, a sound source that can emit a stable frequency and sound level is required to calibrate the system sensitivity; and a microphone calibrator with a frequency of 1kHz and a sound pressure level of 114dB is preferably used as a calibration tool.

[0136] S1.5. Follow the steps below to start and calibrate the signal transmitting, receiving and conditioning devices on the right side of the target vehicle:

[0137] First, make sure that the signal transmitter, signal receiver and signal conditioner on the right side outside the vehicle are powered on and in working condition.

[0138] Next, adjust the gain of the signal receiving device to the third gear to ensure that the received signal strength is moderate. At the same time, in order to avoid carrier frequency conflicts with the left signal transmitting device, resulting in signal crosstalk or interference, it is necessary to adjust the carrier frequency of the right signal transmitting device outside the vehicle to ensure that it is different from the frequency of the left device.

[0139] After confirming that the signal transmitter and receiver have been successfully connected and the connection is correct, use a sound source that can stably emit a specific frequency and sound level to calibrate the system sensitivity. In this example, a microphone calibrator with a frequency of 1kHz and a sound pressure level of 114dB is selected.

[0140] S1.6. In the target vehicle, calibrate the sensitivity of the microphone inside the vehicle.

[0141] S1.7. Set the target vehicle according to the following steps:

[0142] First, start the vehicle and drive onto the test road. Before driving, make sure that the speed through the AA' and BB' intervals has been calculated based on the preset uniform speed. During driving, compare the speed on the vehicle instrument display with the speed data provided by the GPS and CAN systems, and record the corresponding speed value on the vehicle instrument display when the GPS or CAN shows a speed of 50km / h;

[0143] After entering the formal measurement stage, the driver only needs to pay attention to the speed value on the vehicle instrument display when the LED light-emitting diode lights up.

[0144] If the driver can easily view the speed information displayed on the data collector or computer software, the above step of observing the instrument display screen can be omitted, and the speed can be controlled directly according to the speed data on the data collector or software. In this case, the LED light-emitting diode can be placed near the data collector display screen or the position where the software displays the speed, and the speed control should be based on the data provided by the GPS or CAN system, without additional adjustment.

[0145] In addition, as an alternative, the prompt sound module 9-1 and the earphone 10 can also be used to assist the driver in controlling the vehicle speed. The driver only needs to wear the earphone 10 and listen to the prompt sound triggered when the reference point passes the reflector, and can control the vehicle speed according to the prompt sound.

[0146] S1.8. Perform a pre-test on the target vehicle according to the following steps:

[0147] The driver needs to drive the vehicle at a preset uniform speed. When the reference point of the vehicle touches the reflector 8-1 and triggers the corresponding prompt sound or light signal, the driver should start to step on the accelerator pedal to accelerate. Subsequently, when the reference point of the vehicle passes the reflector 8-2 (i.e., line AA') or the reflector 8-3 (i.e., line PP') and triggers the prompt sound or light signal again, the driver needs to pay close attention to the real-time vehicle speed value displayed on the vehicle instrument display screen.

[0148] If the speed displayed at this time is lower than expected, the driver should increase the speed of the uniform driving appropriately; on the contrary, if the speed is too high, the speed should be reduced. This adjustment process should be continued until the vehicle's reference point passes through the reflector 8-2 (AA' line) or the reflector 8-3 (PP' line), and the vehicle speed can meet the established test requirements.

[0149] S1.9. On the test road surface, the driver drives at a constant speed according to the pre-set and adjusted speed, maintaining a stable speed until passing the first reflector (reflector 8-1).

[0150] S2. According to the prompt sound triggered by the first reflector, the target vehicle is controlled to accelerate and pass through the second reflector.

[0151] Step S2 of the embodiment of the present application is specifically as follows:

[0152] When the reference point of the target vehicle passes through the first reflector (reflector 8-1), the driver receives a prompt sound through an earphone (10) or observes a prompt light through the naked eye, and steps on the accelerator pedal according to the prompt sound or prompt light triggered by the first reflector (reflector 8-1), thereby controlling the target vehicle to accelerate and pass through the second reflector (reflector 8-2, reflector 8-3);

[0153] The prompt sound is obtained by receiving the reflected light of the reflective plate through the photoelectric sensor to output a high-level signal, and triggering the prompt sound module (9-1) of the target vehicle to play the prompt sound according to the output duration of the high-level signal; in addition, the prompt sound is an audio signal with a duration of 50 milliseconds and a frequency of 5000 Hz.

[0154] In this embodiment S2, the playing of the prompt tone provides intuitive feedback to the driver, indicating that the vehicle has reached the preset trigger point. This feedback method helps the driver to maintain attention during the test and make timely responses as needed. Since non-contact photoelectric sensors and reflectors are used during the test, safety risks caused by direct contact with the vehicle or road are avoided.

[0155] S3. According to the prompt sound triggered by the second reflector, the target vehicle is controlled to drive past the third reflector at a preset speed.

[0156] Step S3 of the embodiment of the present application is specifically as follows:

[0157] When the reference point of the target vehicle passes the position of the reflector 8-2 (AA' line) or the position of the reflector 8-3 (PP' line) and triggers the prompt sound or prompt light, observe whether the vehicle speed meets the requirements;

[0158] According to the prompt sound or prompt light triggered by the second reflector (reflector 8-2, reflector 8-3), the target vehicle is controlled to drive through the third reflector (reflector 8-4, reflector 8-5) at a preset speed; wherein the preset speed is data calculated according to the vehicle acceleration, speed, and displacement formula, and is a parameter that needs to be determined before the formal test;

[0159] In addition, the driver needs to observe the sound and light prompts emitted when the reference point of the target vehicle passes the reflector to confirm whether the vehicle speed meets the requirement of 50km / h or other vehicle speed requirements when the reference point passes AA' (reflector 8-2) or PP' (reflector 8-3), and determine when to step on and release the accelerator pedal; for example, when the GPS or CAN vehicle speed is 50km / h, the vehicle speed on the instrument display is 53km / h, then when the vehicle reference point passes AA' or PP' (that is, when the LEDs at these two positions are on), the driver should control the vehicle speed within the range of 53km / h±1km / h.

[0160] S4. According to the prompt sound triggered by the third reflector, the target vehicle is controlled to stop accelerating.

[0161] Step S4 of the embodiment of the present application is specifically as follows:

[0162] If the reference point is at the rear end of the target vehicle, when the reference point of the target vehicle passes the second-to-last reflector of the plurality of reflectors, that is, the position of reflector 8-4 (BB' line), the driver controls the target vehicle to stop accelerating by releasing the accelerator pedal according to the prompt sound or prompt light triggered by the second-to-last reflector (reflector 8-4);

[0163] If the reference point is not at the rear end of the target vehicle (the reference point is at the front end or middle of the vehicle), when the reference point of the target vehicle passes the last reflector (reflector 8-5) of the reflectors, the driver controls the target vehicle to stop accelerating by releasing the accelerator pedal according to the prompt sound or prompt light triggered by the last reflector (reflector 8-5).

[0164] This embodiment S4 takes into account the situation that the reference point may be located at different positions of the vehicle (rear end, front end or middle part), and designs different trigger points accordingly. This design enables the test method to be flexibly applied to various vehicle models without making major adjustments due to different vehicle configurations.

[0165] S5. Synchronously collect on-vehicle wired signals and on-ground wireless signals of the target vehicle when the target vehicle is tested on the test road surface using a data collector placed in the target vehicle to obtain vehicle vibration and noise characteristic data of the target vehicle.

[0166] Step S5 of the embodiment of the present application includes S5.1 to S5.2, wherein S5.1 is a process of obtaining vehicle vibration and noise characteristic data, and S5.2 is a process of processing the vehicle vibration and noise characteristic data, specifically:

[0167] S5.1. Press the start button of the data collector about 2 seconds before the reference point passes the reflector 8-1 to start collecting data, and press the end button of the data collector about 2 seconds after releasing the accelerator pedal to end data collection; the screen of the data collector can be operated blindly without distracting the driver's attention, and the test can also be completed by two people, one person driving the vehicle and the other operating the data collector to collect data;

[0168] The test and data collection are repeated on the test road surface in the above manner. The on-vehicle wired signal and the ground wireless signal of the target vehicle when the target vehicle is tested on the test road surface are synchronously collected by a data collector placed in the target vehicle to obtain the vehicle vibration and noise characteristic data of the target vehicle after several tests. Among them, the number of tests is preferably 4 times, and the number of repeated measurements can be determined according to the requirements of each region.

[0169] In addition, the wired signal on the vehicle and the wireless signal on the ground include a sound pressure simulation signal, and the specific method of obtaining the sound pressure simulation signal is as follows:

[0170] Arrange a number of noise measurement points on the test road surface; wherein the number of noise measurement points include vehicle exterior passing noise measurement points or vehicle exterior pedestrian warning sound measurement points arranged according to different test regulations;

[0171] The weak sound pressure signal collected by the microphone is amplified by the preamplifier, the amplified signal is conditioned into a standard analog signal by the signal conditioning device, and the conditioned standard analog signal is transmitted to the signal transmitting device; wherein the weak sound pressure signal is a sound pressure signal measured by a target vehicle passing through a plurality of noise measuring points when the target vehicle is tested on a test road surface;

[0172] After the standard analog signal is converted into a modulated signal suitable for wireless transmission by a signal transmitting device, it is sent to a signal receiving device for demodulation, and the sound pressure analog signal obtained after the signal demodulation is collected by a data collector;

[0173] Each group of signal transmitting devices and signal receiving devices is provided with a different carrier frequency; and the devices involved in data collection are all devices in the first integrated measurement system or the second integrated measurement system.

[0174] By arranging multiple noise measurement points on the test road surface, this embodiment S5.1 can flexibly choose to arrange the vehicle's outside passing noise measurement points or the vehicle's outside pedestrian warning sound measurement points according to different test regulations to meet different test requirements. The weak sound pressure signal collected by the microphone is amplified by a preamplifier, and the amplified signal is conditioned into a standard analog signal by a signal conditioning device, which improves the stability and accuracy of the signal and is conducive to subsequent fault diagnosis and analysis. The standard analog signal is converted into a modulated signal suitable for wireless transmission by a signal transmitting device, and sent to a signal receiving device for demodulation, thereby realizing wireless transmission of the signal and avoiding the wiring complexity and limitations that may be caused by wired transmission. In addition, each group of signal transmitting devices and signal receiving devices is provided with different carrier frequencies, which can effectively avoid signal interference between different measuring points and ensure accurate transmission and reception of data.

[0175] S5.2. Perform spectrum analysis on the ground wireless signal to obtain spectrum analysis results;

[0176] Perform fault diagnosis on the target vehicle based on the spectrum analysis results.

[0177] Based on a portable computer and data acquisition and analysis, control and display software 11, observe and record relevant values ​​of the vehicle vibration and noise characteristic data, including but not limited to the voltage value of the photoelectric sensor, the opening of the driving pedal, the vehicle speed, the engine speed, the motor speed, the sound pressure level of the measuring point inside the vehicle, the acceleration of the measuring point inside the vehicle, and the sound pressure level of the measuring points on the left and right sides outside the vehicle, etc. These data will show different trends over time;

[0178] While observing the data, the vehicle speed data is integrated to obtain the displacement information of the vehicle; the analysis data processed by the portable computer and the data acquisition and analysis, control and display software 11 is obtained;

[0179] Eliminate unqualified data from the analysis data. If the number of measurements of the data after the elimination does not meet the preset standard, repeat the above test until the number of measurements of qualified data meets the preset standard.

[0180] Based on the analysis data that meets the preset standards, professional data processing and analysis software, such as Test.Lab, Artemis or other equivalent analysis tools, are used to conduct in-depth analysis (such as FFT analysis, time-frequency analysis, order analysis, etc.) on the acceleration signals and sound pressure signals of the measuring points inside the vehicle, as well as the sound pressure signals of the measuring points outside the vehicle, so as to determine the main sources and causes of vibration noise.

[0181] In S5.2 of this embodiment, spectrum analysis can quickly capture abnormal characteristics of the signal, such as frequency offset, signal attenuation, etc., thereby shortening the fault diagnosis time and improving the diagnosis efficiency, so that the fault or abnormality in the target vehicle can be accurately located.

[0182] To apply the embodiments of this application, please refer to Figure 5-7 , Figure 5 This is a schematic diagram of the test data of accelerating through the measurement site according to GB1495-2002 provided in the embodiment of the present application, which shows the data obtained by accelerating through the measurement site test according to GB1495-2002 based on the measurement scheme of Example 1, specifically:

[0183] According to the GB1495-2002 standard, a number of dynamic parameters of a vehicle are recorded in detail while it is accelerating through the measurement site, including the voltage signal triggered by the reflector, the accelerator pedal opening, the vehicle speed, the displacement of the vehicle relative to the site, the sound pressure level inside and outside the vehicle, etc. All parameters are monitored over time.

[0184] Data analysis shows that the vehicle acceleration process starts when the reference point is 12.6 meters away from the AA' line. At this time, the driver presses the accelerator pedal and the vehicle enters the test area at a speed of 50.8 km / h at full throttle. As the acceleration progresses, when the reference point passes the midpoint PP' line, the vehicle speed reaches 56.6 km / h; the acceleration continues until the reference point passes the BB' line, and the vehicle speed has increased to 61.8 km / h. However, the acceleration process does not end immediately when the reference point passes the BB' line, but is delayed by 9.2 meters, that is, the driver releases the accelerator pedal 9.2 meters after the reference point passes the BB' line.

[0185] During the acceleration of the vehicle, the maximum sound pressure level measured at a distance of 7.5 meters from the left side of the vehicle is 70.9dBA, and this peak value corresponds to the moment when the reference point passes through the BB' line. Considering that the total length of the test vehicle is 5.2 meters and the reference point is set at the front end of the vehicle, it can be judged that the position where the driver releases the accelerator pedal in this measurement is about 4 meters later than the ideal state, which does not meet the requirements of regulatory standards and may cause the measured maximum sound pressure level value to be too high.

[0186] and, Figure 5 The relative displacement data of the vehicle to the site is obtained by integrating the vehicle speed data, and the rest of the data are measured by sensors and data collectors. In addition, the vehicle speed data can be differentiated to obtain the acceleration value at each moment during the test, and the average acceleration of each section of the interval can be calculated based on the relationship between displacement, speed, and acceleration to determine whether it meets the standard requirements.

[0187] Figure 6 This is a table showing the test data of the accelerated passing measurement site according to ECE R51.03 provided in the embodiment of the present application, which shows the data obtained by the accelerated passing measurement site test according to ECE R51.03 based on the measurement scheme of the first embodiment;

[0188] like Figure 6 As shown in the figure, a series of key performance parameters recorded by a hybrid vehicle with a non-lockable gear in the process of accelerating through the measurement site in accordance with the ECE R51.03 standard are shown. Specifically, they include: the sound pressure level at 7.5 meters outside the vehicle, the vehicle speed at each measurement point, the average acceleration within the interval, the deviation between each acceleration and the four average accelerations, and the engine speed at each measurement point. It is worth noting that the acceleration values ​​listed in the chart are all obtained through precise calculations based on the mathematical relationship between displacement, speed and acceleration.

[0189] Figure 7 The spectrum diagram of the sound pressure level inside the vehicle and the sound pressure level outside the vehicle provided by the curve data of the embodiment of the present application shows Figure 6 The corresponding comparison of the noise spectra inside and outside the car measured simultaneously; Figure 7 It can be seen that the noise outside the car is mainly concentrated in the frequency band of 1000 Hz to 1200 Hz, which is mainly contributed by tire radiation noise.

[0190] To apply the embodiments of this application, please refer to Figure 8-9 , Figure 8 : is a comparison diagram of wireless signal and wired signal delays in different solutions provided in the embodiments of the present application, showing the comparison of wireless signal and wired signal delays under different solutions, specifically:

[0191] In a static test environment, a 100Hz sine wave signal is transmitted to the data collector via a wired transmission path and two different wireless transmission schemes (equipped with their own signal transceiver and conditioning devices). Subsequently, the time domain waveforms obtained by these transmission schemes are compared and analyzed. In the figure, the solid line represents the wired transmission signal, and the dotted line and dash-dot line represent the signals of the two wireless transmission schemes respectively;

[0192] The observation results show that both wireless transmission schemes have a certain signal delay compared to wired transmission, ranging from 1 millisecond to 3 milliseconds. Nevertheless, this delay level still meets the established usage requirements and ensures the effectiveness and accuracy of data transmission.

[0193] Fig. 9 : is a comparison diagram of wireless signal and wired signal spectra in different schemes provided in the embodiments of the present application, which shows the comparison of wireless signal and wired signal spectra in different schemes, specifically:

[0194] Under static test conditions, the sound pressure signal of a microphone is transmitted to the data collector through a wired transmission path and three different wireless transmission schemes (each equipped with a signal transceiver and conditioning device), and the FFT frequency domain waveforms obtained by these transmission paths are compared and analyzed. In the figure, the solid line represents the frequency domain waveform of the wired transmission signal, and the long dashed line, short dashed line and dotted line correspond to the frequency domain waveforms of the three wireless transmission schemes.

[0195] By observing the comparison results, it can be found that within the frequency range of 30Hz to 10kHz, the frequency domain waveforms of the three wireless transmission schemes are basically consistent with the frequency domain waveforms of the wired transmission scheme, showing a high degree of overlap. Further analysis shows that the maximum difference between the weighted total sound pressure level of wireless scheme A and the wired signal data is only 0.16dBA. This tiny difference fully meets the established usage requirements and verifies the accuracy and reliability of the wireless transmission scheme in sound pressure signal transmission.

[0196] Overall, this embodiment has the following beneficial effects:

[0197] This application sets clear test steps, including driving at a constant speed, accelerating, driving at a preset speed, and stopping acceleration. These standardized test processes help ensure the consistency of each test, making it easier to compare and analyze different test data. Among them, by accurately controlling the driving path and speed of the target vehicle on the test road, the operational complexity and time consumption caused by the numerous components in the traditional measurement method are reduced. The combination of the reflector and the prompt sound makes the test process more concise and clear, thereby improving the measurement efficiency. In addition, the driving state of the vehicle is controlled according to the prompt sound triggered by the reflector, which can achieve flexible adjustment under different test requirements and regulatory requirements. This flexibility allows the method to adapt to a variety of standards and test items. In addition, through the prompt sound triggered by the reflector, the driver can accurately know when to step on and release the accelerator pedal. This precise control reduces the error caused by improper operation of the driver and helps to improve the accuracy of the measurement data.

[0198] In summary, the present application can solve the problem of low measurement efficiency caused by the large number of components in the traditional measurement method by simplifying the component structure; by flexibly adjusting the position of the reflector, it can meet the needs of various standards and test items, and solve the problem that the fixed position of the reflector is difficult to meet the diverse requirements of regulations; and, by accurately prompting the driver's operation, it can solve the problem of low measurement accuracy caused by the traditional method's inability to accurately indicate the specific time and position of the driver's pressing and releasing the accelerator pedal.

[0199] Embodiment 2:

[0200] See also Fig.10, an embodiment of the present application provides a device for measuring vehicle vibration and noise characteristic data, including a constant speed module 10, an acceleration module 20, a control module 30, a release module 40 and a processing module 50;

[0201] The constant speed module 10 is used to control the target vehicle to travel at a constant speed on the test road surface and pass through the first reflector; wherein the test road surface is provided with a plurality of reflectors distributed along the center line of the road surface;

[0202] The acceleration module 20 is used to control the target vehicle to accelerate and drive past the second reflector according to the prompt sound triggered by the first reflector;

[0203] The control module 30 is used to control the target vehicle to drive past the third reflector at a preset speed according to the prompt sound triggered by the second reflector;

[0204] The release module 40 is used to control the target vehicle to stop accelerating according to the prompt sound triggered by the third reflector;

[0205] The processing module 50 is used to synchronously collect the on-vehicle wired signals and the ground wireless signals of the target vehicle when the target vehicle is tested on the test road surface according to the data collector placed in the target vehicle, so as to obtain the vehicle vibration and noise characteristic data of the target vehicle.

[0206] In one embodiment, the constant speed module 10 includes a mounting unit, a first setting unit, a second setting unit, an adjustment unit, a third setting unit, a fourth setting unit, a calibration unit, a vehicle setting unit, a pre-test unit, and a constant speed unit;

[0207] Among them, the installation unit is the process of setting the first integrated measurement system, the first setting unit is the process of setting the device required for the test, the second setting unit and the adjustment unit are the process of setting the reflector, the third setting unit is the process of initializing and calibrating the device, the fourth setting unit is the process of starting and calibrating the device, the calibration unit is the process of data calibration, the vehicle setting unit is the process of initial setting the vehicle, the pre-test unit is the process of pre-testing, and the uniform speed unit is the process of formal testing;

[0208] The installation unit is used to set up the first integrated measurement system and install the photoelectric sensor and other related equipment in the first integrated measurement system at a preset reference point of the target vehicle; wherein the position of the reference point is determined according to the installation position of the powertrain, that is, the installation position of the powertrain is the reference point;

[0209] In addition, the first integrated measurement system is composed of a data collector 1-1 (universal multi-channel data collector), a bus signal acquisition module 2, a satellite navigation system module 3, a GPS antenna 4, an acceleration sensor 5, a microphone (including a preamplifier) ​​6, a photoelectric sensor 7, a reflector 8, a prompt sound module 9-1, an earphone 10, a portable computer and data acquisition and analysis, control and display software 11, a signal conditioning device 12, a signal transmitting device 13, a signal receiving device 14 and other partial structures; specifically:

[0210] ① Data collector 1-1: A general-purpose multi-channel data collector is used, with a built-in lithium battery and external DC power supply, equipped with at least 4 analog input channels, capable of achieving a full-channel parallel sampling rate of more than 50kHz, and an analog-to-digital resolution between 16 and 24 bits. In addition, the maximum range of the analog input channel exceeds 10V, and each channel is provided with at least 3 ranges that can be programmably adjusted. The data acquisition accuracy is higher than one thousandth of the full range, and the background noise of each channel can be ensured to be less than 50μV RMS. Its embodiments include Siemens SCADAS MOBILE series, Hyde headlab series data acquisition front ends, or other general data acquisition front ends that meet the requirements.

[0211] ②Bus signal acquisition module 2: It can exist as an independent unit or be integrated into the data collector 1-1. It can decode the vehicle accelerator pedal opening, vehicle speed, motor speed, engine speed and other signals in real time according to the imported vehicle model DBC file, and it is also compatible with the bus system in CAN / CAN FD data format for communication.

[0212] ③ Satellite navigation system module 3: It can be used as an independent component or integrated into the data collector 1-1, and at least includes a module that can communicate with satellite positioning systems such as GPS / Beidou / GLONASS to calculate information such as vehicle speed and vehicle position.

[0213] ④GPS antenna 4: It is a universal type, equipped with a preamplifier and a magnetic mount, which is easy to be adsorbed on the outside of the vehicle body. Its cable length is not less than 2 meters, and the interface must match the satellite navigation system module 3. The satellite navigation system module 3 and GPS antenna 4 adopt a redundant design, which is intended to be used as a backup solution when the vehicle bus network cannot obtain the bus signal.

[0214] ⑤ Accelerometer 5: It adopts ICP / IEPE ceramic or quartz piezoelectric shear type design, with a power supply voltage of 24V, a flat frequency response range of more than 2Hz to 5000Hz, and an applicable temperature range of more than 0℃ to 120℃. Its sensitivity range (deviation 5%) is between 40mv / g and 100mv / g, the lateral sensitivity does not exceed 5%, and the amplitude nonlinearity is not more than 1%.

[0215] ⑥ Microphone (including preamplifier) ​​6: 1 / 2 inch free-field microphone, in line with IEC61672 Class 1 accuracy, dynamic range greater than 20dBA ~ 120dBA, flat frequency response range greater than: 20Hz ~ 20kHz, sensitivity 50mv / pa.

[0216] ⑦ Photoelectric sensor 7: It adopts diffuse reflection design, can be 3-wire or 4-wire PNP normally open type, the power supply voltage range is between 10V and 30V, the detection distance can be adjusted within 500mm to 1000mm, and the photoelectric sensor can be arranged according to different regulatory requirements. In addition, the sensor can also use other types of photoelectric detection high-level output switch sensors, such as photoelectric sensors for detecting displacement differences.

[0217] ⑧Reflector 8: It can be made of metal or non-metal material, and its shape is a rectangular cross-section thin-walled structure with a width between 20mm and 100mm and a height between 10mm and 50mm. The length can be selected within the range of 500mm to 1000mm. The surface of the reflector should be white or other light colors that form a significant color difference with the road surface. Alternatively, the paint marking line can be directly sprayed on the road surface. The number of reflectors matches the model parameters of the photoelectric sensor 7, and does not exceed 6 pieces.

[0218] ⑨ Prompt sound module 9-1: It has the function of storing audio files and supports the input of edited prompt sound files. The prompt sound file is a sine wave MP3 format audio file with a duration of 50ms and a frequency of 5000Hz. The trigger input voltage range is between 5V and 24V, and the broadcast delay after triggering is less than 10ms. The trigger mechanism uses a comparator to detect the high-level signal output by the photoelectric sensor. The reference voltage is set to 3V. Once the input voltage exceeds this threshold, the comparator outputs a high-level trigger signal. In view of the short duration of the trigger signal (10ms to 15ms), a delay circuit is specially designed to ensure that the signal is reliably captured. A 555 timer is used to achieve delay and signal shaping. The delay is slightly longer than the longest trigger signal duration to ensure that the signal is fully captured;

[0219] In addition, the microcontroller unit (MCU) selected must have audio decoding and output capabilities, such as the STM32 series or ESP32 series, etc., configured to read the audio file from the memory after receiving the trigger signal, and play it through the audio output pin. The audio output circuit connects the MCU audio output pin to the audio amplifier circuit, using a low-power audio amplifier integrated circuit (such as LM386) or an advanced amplifier module that adapts to the 5V to 15V input voltage range. To provide a stable voltage for the MCU and amplifier circuit, a wide voltage range regulator (such as LM7805, LM1117, etc.) is used for voltage conversion, or a switching regulator (such as LM2576, LM2596, etc.) is selected to replace the linear regulator for power consumption and efficiency considerations.

[0220] ⑩ Earphone 10: uses universal 3.5mm three-section stereo connector.

[0221] Portable computer and data acquisition and analysis, control and display software 11: The hardware configuration requirements include: main frequency exceeding 2GHz, RAM capacity exceeding 8GB, ROM capacity exceeding 500GB, and display screen size not less than 15.6 inches. The software part must be aretemis version 10.5 or above, or testlab version 19 and above.

[0222] Signal conditioning device 12: This device mainly provides 2mA constant current power supply for IEPE microphone (including preamplifier) ​​6, which is used to collect the sound pressure signal outside the vehicle and convert it into a standard 0V to 5V AC voltage signal. The background noise of this device is less than 0.5μV, and one specific model is 61000.

[0223] Signal transmitting device 13 and signal receiving device 14: One of the embodiments is WAS-101, and its carrier frequency range is set between 570MHz and 600MHz. After the sound pressure signal is sampled and encoded, it is loaded onto the carrier and output by digital modulation. The output gain is adjustable, and 15 sets of adjustable carrier frequencies are provided. The working principle of the wireless transmission system is summarized as follows: the sound pressure signal of the noise outside the vehicle or the pedestrian warning sound measurement point is collected by the microphone, amplified by the preamplifier, and converted into a standard analog signal by the signal conditioning device. The signal is transmitted to the signal transmitting device via a wired manner, and the latter modulates the sound pressure signal. The modulated signal is amplified and emitted by the antenna in the form of UHF frequency band electromagnetic waves. After the antenna of the signal receiving device receives the transmitted carrier signal, it performs a demodulation operation to restore the original sound pressure analog signal, and then sends it to the analog signal acquisition channel of the data collector via a wired connection. When multiple sound pressure signal measurement points are set outside the vehicle, each group of signal transmitting and receiving devices (corresponding to each channel) can be configured with a different carrier frequency to ensure that there is no frequency interference between the signals of each channel;

[0224] Furthermore, the signal transmitting device 13, the signal conditioning device 12 and the external microphone (including the preamplifier) ​​6 are arranged on a tripod on the PP' line, and the signal receiving device 14 is arranged outside the vehicle body and fixed by a magnetic base or other fixing methods.

[0225] To apply the embodiments of this application, please refer to Figure 2 , Figure 2 It is a schematic diagram of the first structural composition provided in an embodiment of the present application, which shows the specific structure of the first comprehensive measurement system.

[0226] To apply the embodiments of this application, please refer to Figure 3 , Figure 3 is a schematic diagram of a second structural composition provided in an embodiment of the present application, showing the specific structure of another integrated measurement system (second integrated measurement system) provided in this embodiment;

[0227] Moreover, the difference between the second integrated measurement system and the first system is mainly reflected in the data collector 1-2. The collector of the second integrated measurement system is a portable integrated type, integrating data collection, control and display functions, equipped with an embedded operating system and storage device, supporting data collection and analysis processing in stand-alone mode, and can also be connected to a computer and its supporting host computer software for data operation. This design allows a single driver to complete vehicle driving and data collector operations. For example, Hyde's SQIII data collector can be used, which supports blind operation mode and can display data such as vehicle speed in real time. Combined with the prompt sound module 9-1 (which can be replaced in this embodiment) or the light emitter 9-2, the driver can adjust the vehicle operation accordingly to ensure that the vehicle operating parameters meet regulatory standards. During data collection, post-processing such as Siemens testlab software is still used to obtain operating data such as vehicle acceleration;

[0228] also, Figure 3 Compared to Figure 2 Another significant change of the system shown is that the prompt sound module 9-1 and the earphone 10 are cancelled, and the light emitter 9-2 is used instead. The light emitter is placed on the vehicle instrument display screen (or near the position where the data collector or acquisition software displays the vehicle speed), and the driver controls the vehicle by observing the vehicle speed corresponding to the light emission moment to meet the specified operating requirements.

[0229] It should be noted that the measurement of the vehicle vibration and noise characteristic data in this embodiment is completed based on the integrated measurement system (the first integrated measurement system or the second integrated measurement system) provided in this embodiment.

[0230] The first setting unit is used to ensure that components 1-2 to 14 in the first integrated measurement system are correctly connected, and then turn on the power switch of the data collector. Next, the DBC file for the vehicle to be tested is properly stored in the memory card of the collector. At this time, the required channels need to be opened, including analog channels, CAN channels, and GPS channels.

[0231] When configuring the data logger parameters, key information such as channel name, coupling mode, and sensitivity of the input accelerometer should be specified. In particular, for wired accelerometers and in-vehicle microphones, the coupling mode should be ICP / IEPE; the coupling mode of photoelectric sensors is DC; and for wireless transmission of out-vehicle microphones, the coupling mode is AC.

[0232] In addition, the data interaction mode, data frame format, sampling point location, baud rate and other parameters of the CAN channel need to be set according to the actual situation of the vehicle CAN data type. At the same time, in order to meet the needs of online monitoring and viewing, the CAN channel data to be displayed also needs to be set, which includes but is not limited to key indicators such as accelerator pedal opening, vehicle speed, motor speed and engine speed.

[0233] The second setting unit is used to arrange five reflectors (i.e., the reflectors 8 of the first integrated measurement system) at the center line of the test road surface along the vehicle travel direction, namely, reflector 8-1, reflector 8-2, reflector 8-3, reflector 8-4 and reflector 8-5; and the number and placement positions of these reflectors can be adjusted according to needs;

[0234] An adjustment unit, used for adjusting the plurality of reflective plates, so that the photoelectric sensor can trigger sensing according to the reflected light of the plurality of reflective plates to output a high level;

[0235] The placement positions of the five reflectors are symmetrical about the test section of the test road. If the target vehicle needs to be tested from both ends of the test section, an auxiliary reflector (reflector 8-6) is added after the second reflector at the preset end of the test section.

[0236] By setting the width of the auxiliary reflector to be smaller than a preset value, when the reference point of the target vehicle passes through the auxiliary reflector (reflector 8-6), the duration of the high-level signal output by the photoelectric sensor is shorter than the trigger threshold required by the prompt sound module (9-1), thereby not triggering the prompt sound module to play the prompt sound.

[0237] To apply the embodiments of this application, please refer to Figure 4 , Figure 4 This is a schematic diagram of the arrangement of the reflective plate for the noise test provided in the embodiment of the present application. Figure 4 The installation method of the reflector is described in detail:

[0238] When conducting a vehicle pass-by noise test in accordance with GB1495 or ECE R51 standards, several reflectors must be precisely arranged along the CC' centerline of the vehicle's travel direction. Different reflectors can be set according to the position of the reference points to ensure the accuracy and effectiveness of the test. The following is an explanation using five reflectors as an example:

[0239] The first reflector 8-1 should be placed before the AA' line, and its distance from the AA' line is equal to the vehicle length minus the distance from the reference point to the front end of the vehicle. If the reference point of the target vehicle is located at the front or rear end of the vehicle, the distance between the reflector and the AA' line is the vehicle length;

[0240] The second reflector 8-2: needs to be precisely positioned on the AA' line as a key reference;

[0241] The third reflector 8-3: should be placed on the PP' line as an important reference point during the vehicle's movement;

[0242] The fourth reflector 8-4: needs to be set on the BB' line to further monitor the noise performance of the vehicle;

[0243] The fifth reflector 8-5 should be placed after the BB' line, and its distance from the BB' line should be equal to the distance between the first reflector 8-1 and the AA' line to ensure the symmetry and consistency of the test;

[0244] In addition, the five reflectors need to be arranged symmetrically about the PP' line. If the test requires the vehicle to enter the line from two directions for testing, an additional reflector 8-6 needs to be added between AA' and PP' or between PP' and BB' to accurately determine the driving direction of the vehicle.

[0245] In addition, when conducting the ECE R51 vehicle noise test, the arrangement of the reflectors is also adjusted according to the different requirements of Method A and Method B to ensure the accuracy and effectiveness of the test:

[0246] ① If the test is conducted in accordance with ECE R51 Method A, it is necessary to ensure that the vehicle travels at a stable acceleration between the AA' and BB' lines. The specific requirements are: when the reference point reaches the AA' line, the vehicle speed should be accurately controlled within the range of 50km / h±1km / h; and when the rear end of the vehicle exits the BB' line, the driver should release the accelerator pedal. In this case, in order to simplify the test process, it is only necessary to arrange reflectors 8-1 (located before the AA' line, used to control vehicle acceleration), 8-2 (located on the AA' line, as a reference point for the vehicle traveling at a stable acceleration), 8-4 (located on the BB' line, used to control the vehicle to stop accelerating when the rear end of the vehicle passes this position) and 8-5 (located after the BB' line, for vehicles whose reference point is not at the rear end of the vehicle, used to determine that the vehicle stops accelerating when the rear end of the vehicle passes this position).

[0247] ② If the test is conducted in accordance with ECE R51 Method B, the vehicle is also required to maintain a stable acceleration between the AA' and BB' lines. However, the difference is that it is necessary to ensure that the vehicle speed reaches 50km / h±1km / h when the reference point reaches the PP' line, and the accelerator pedal is released when the rear end of the vehicle passes the BB' line. In addition, if the reference point is not located at the rear end of the vehicle, in order to optimize the test layout, it is only necessary to arrange reflectors 8-1 (also located before the AA' line), 8-3 (located on the PP' line, as a key reference point for accelerating to the target speed) and 8-5 (located after the BB' line, used to determine that the vehicle stops accelerating when the rear end of the vehicle passes this position).

[0248] It should be noted that in the vehicle noise test of the ECE R51 standard, Method A and Method B are two different test schemes; Method A requires the vehicle to travel at a steady acceleration in the test area from line AA' to line BB', and the reference point must reach the target speed range when it reaches line AA'; Method B also requires the vehicle to travel at a steady acceleration in the test area, but this time the reference point must reach the target speed range when it reaches line PP'.

[0249] In the second setting unit and the adjustment unit of this embodiment, the position of the reflector can be set according to the needs, so that the test process becomes relatively simple. The driver only needs to drive at a constant speed according to the preset speed without any additional operation or judgment. Based on the precise coordination of the photoelectric sensor and the reflector, and the control of the vehicle's constant speed, the accuracy of the test results can be significantly improved;

[0250] Moreover, the symmetrical arrangement of the five reflectors ensures that the vehicle's driving trajectory on the test section is accurately recorded, and the symmetrical arrangement of the reflectors can reduce the complexity of the test process. In addition, the setting of the auxiliary reflectors enables the test system to adapt to different test requirements. When the target vehicle needs to be tested from both ends of the test section, the auxiliary reflectors can clearly identify the vehicle's driving direction without large-scale adjustment or resetting of the test equipment;

[0251] By setting up auxiliary reflectors and controlling their width, the output of the photoelectric sensor can be precisely controlled. When a vehicle passes by the auxiliary reflector, only a high-level signal is generated without triggering a prompt tone, which helps reduce interference and noise during the test and makes the test process smoother. In addition, it allows in-line testing from both ends of the test section without changing the overall layout of the test equipment or reconfiguring the test parameters. This method increases the flexibility of the test and enables it to adapt to different test needs and scenarios.

[0252] Compared with the present application, the prior art only has partial reflectors, such as reflectors 8-2, 8-4, and 8-6, wherein reflector 8-6 is used to determine the direction of the vehicle. The program sets that the driver will step on the accelerator pedal only after hearing the prompt sound when the vehicle enters AA', which does not meet the pre-acceleration requirements of the ECE R51.03 regulations. There is no prompt sound when passing the center PP', which is not convenient for the driver to control the vehicle to pass the PP' line speed of 50km / h±1km / h according to the ECE R51.03 requirements. When the rear end of the vehicle exits the BB' line, a long prompt sound is still used to prompt the driver to stop accelerating through the BB' line through the reference point, and the reference points of the front and mid-mounted engines are not at the rear end of the vehicle, which will cause different drivers to react at different speeds after hearing the long prompt sound, and release the accelerator pedal at different prompt sound moments, resulting in the actual stop acceleration position being the rear end of the vehicle in front of or behind the BB' line, which may cause a large test error and does not meet regulatory requirements.

[0253] The installation unit, the first setting unit, the second setting unit and the adjustment unit of this embodiment innovatively use a single data collector, which can be placed in the vehicle to simultaneously obtain comprehensive data from vehicle sensors and ground sensors, covering diversified information such as acceleration, sound pressure, GPS signals, CAN bus signals and photoelectric sensor signals. The layout of the ground sound pressure measurement points is flexible and can be flexibly adjusted according to different test regulations. At the same time, the layout of the reflector also complies with the test standards and project requirements, and accurately calibrates the position of the vehicle relative to the test site;

[0254] This solution is widely used in pedestrian warning sound testing, pass-by noise assessment and other scenarios that require synchronous monitoring of data inside and outside the vehicle. The in-vehicle warning sound is triggered by a dedicated module and a high-level linkage with the photoelectric sensor, and is directly transmitted to the driver in the form of headphones. It is completely independent of the data acquisition system and its software, ensuring that the in-vehicle noise measurement is not interfered with, and achieving harmonious coexistence of the warning sound and the in-vehicle noise;

[0255] The data collector of this solution has excellent performance, with a sampling rate of 100kHz and an analog-to-digital resolution of 24 bits, showing the dual advantages of high precision and high anti-interference ability. The signal transceiver device shows strong signal transmission capability, covering a wide range of 50 meters, with a flat frequency response range from 30Hz to 17kHz and a delay of less than 3 milliseconds, ensuring the efficiency and accuracy of wireless transmission and collection of external noise, and providing a solid data foundation for spectrum analysis and fault diagnosis.

[0256] The third setting unit is used to initialize and calibrate the signal transmitting device, the signal receiving device and the signal conditioning device on the left side outside the target vehicle according to the following steps:

[0257] First, turn on the power switches of the signal transmitter, signal receiver and signal conditioner on the left side outside the vehicle to ensure that all devices are in working condition.

[0258] Next, adjust the gain of the signal receiving device to the third level to ensure that the received signal strength is moderate for subsequent processing and analysis.

[0259] After confirming that the signal transmitting and receiving devices have been successfully connected, a sound source that can emit a stable frequency and sound level is required to calibrate the system sensitivity; and a microphone calibrator with a frequency of 1kHz and a sound pressure level of 114dB is preferably used as a calibration tool.

[0260] The fourth setting unit is used to start and calibrate the signal transmitting, receiving and conditioning device on the right side of the exterior of the target vehicle according to the following steps:

[0261] First, make sure that the signal transmitter, signal receiver and signal conditioner on the right side outside the vehicle are powered on and in working condition.

[0262] Next, adjust the gain of the signal receiving device to the third gear to ensure that the received signal strength is moderate. At the same time, in order to avoid carrier frequency conflicts with the left signal transmitting device, resulting in signal crosstalk or interference, it is necessary to adjust the carrier frequency of the right signal transmitting device outside the vehicle to ensure that it is different from the frequency of the left device.

[0263] After confirming that the signal transmitter and receiver have been successfully connected and the connection is correct, use a sound source that can stably emit a specific frequency and sound level to calibrate the system sensitivity. In this example, a microphone calibrator with a frequency of 1kHz and a sound pressure level of 114dB is selected.

[0264] The calibration unit is used to calibrate the sensitivity of the microphone in the target vehicle.

[0265] The vehicle setting unit is used to set the target vehicle according to the following steps:

[0266] First, start the vehicle and drive onto the test road. Before driving, make sure that the speed through the AA' and BB' intervals has been calculated based on the preset uniform speed. During driving, compare the speed on the vehicle instrument display with the speed data provided by the GPS and CAN systems, and record the corresponding speed value on the vehicle instrument display when the GPS or CAN shows a speed of 50km / h;

[0267] After entering the formal measurement stage, the driver only needs to pay attention to the speed value on the vehicle instrument display when the LED light-emitting diode lights up.

[0268] If the driver can easily view the speed information displayed on the data collector or computer software, the above step of observing the instrument display screen can be omitted, and the speed can be controlled directly according to the speed data on the data collector or software. In this case, the LED light-emitting diode can be placed near the data collector display screen or the position where the software displays the speed, and the speed control should be based on the data provided by the GPS or CAN system, without additional adjustment.

[0269] In addition, as an alternative, the prompt sound module 9-1 and the earphone 10 can also be used to assist the driver in controlling the vehicle speed. The driver only needs to wear the earphone 10 and listen to the prompt sound triggered when the reference point passes the reflector, and can control the vehicle speed according to the prompt sound.

[0270] The pre-test unit is used to pre-test the target vehicle according to the following steps:

[0271] The driver needs to drive the vehicle at a preset uniform speed. When the reference point of the vehicle touches the reflector 8-1 and triggers the corresponding prompt sound or light signal, the driver should start to step on the accelerator pedal to accelerate. Subsequently, when the reference point of the vehicle passes the reflector 8-2 (i.e., line AA') or the reflector 8-3 (i.e., line PP') and triggers the prompt sound or light signal again, the driver needs to pay close attention to the real-time vehicle speed value displayed on the vehicle instrument display screen.

[0272] If the speed displayed at this time is lower than expected, the driver should increase the speed of the uniform driving appropriately; on the contrary, if the speed is too high, the speed should be reduced. This adjustment process should be continued until the vehicle's reference point passes through the reflector 8-2 (AA' line) or the reflector 8-3 (PP' line), and the vehicle speed can meet the established test requirements.

[0273] The constant speed unit is used for the driver to drive at a constant speed on the test road surface according to a pre-set and adjusted vehicle speed, and to maintain a stable speed until passing the first reflector (reflector 8-1).

[0274] In one embodiment, the acceleration module 20 includes an acceleration unit;

[0275] The acceleration unit is used for, when the reference point of the target vehicle passes through the first reflector (reflector 8-1), the driver receives a prompt sound through an earphone (10) or observes a prompt light through the naked eye, and steps on the accelerator pedal according to the prompt sound or prompt light triggered by the first reflector (reflector 8-1), thereby controlling the target vehicle to accelerate and pass through the second reflector (reflector 8-2, reflector 8-3);

[0276] The prompt sound is obtained by receiving the reflected light of the reflective plate through the photoelectric sensor to output a high-level signal, and triggering the prompt sound module (9-1) of the target vehicle to play the prompt sound according to the output duration of the high-level signal; in addition, the prompt sound is an audio signal with a duration of 50 milliseconds and a frequency of 5000 Hz.

[0277] In the acceleration module 20 of this embodiment, the playing of the prompt tone provides intuitive feedback to the driver, indicating that the vehicle has reached the preset trigger point. This feedback method helps the driver to maintain attention during the test and make timely responses as needed. Since non-contact photoelectric sensors and reflectors are used during the test, safety risks caused by direct contact with the vehicle or road are avoided.

[0278] In one embodiment, the control module 30 is specifically:

[0279] When the reference point of the target vehicle passes the position of the reflector 8-2 (AA' line) or the position of the reflector 8-3 (PP' line) and triggers the prompt sound or prompt light, observe whether the vehicle speed meets the requirements;

[0280] According to the prompt sound or prompt light triggered by the second reflector (reflector 8-2, reflector 8-3), the target vehicle is controlled to drive through the third reflector (reflector 8-4, reflector 8-5) at a preset speed; wherein the preset speed is data calculated according to the vehicle acceleration, speed, and displacement formula, and is a parameter that needs to be determined before the formal test;

[0281] In addition, the driver needs to observe the sound and light prompts emitted when the reference point of the target vehicle passes the reflector to confirm whether the vehicle speed meets the requirement of 50km / h or other vehicle speed requirements when the reference point passes AA' (reflector 8-2) or PP' (reflector 8-3), and determine when to step on and release the accelerator pedal; for example, when the GPS or CAN vehicle speed is 50km / h, the vehicle speed on the instrument display is 53km / h, then when the vehicle reference point passes AA' or PP' (that is, when the LEDs at these two positions are on), the driver should control the vehicle speed within the range of 53km / h±1km / h.

[0282] In one embodiment, the release module 40 includes a tail unit and a trigger unit;

[0283] The tail unit is used for controlling the target vehicle to stop accelerating by releasing the accelerator pedal according to the prompt sound or prompt light triggered by the penultimate reflector (reflector 8-4) when the reference point of the target vehicle passes the penultimate reflector of the plurality of reflectors, i.e., the position of reflector 8-4 (BB' line) if the reference point is at the tail end of the target vehicle;

[0284] The trigger unit is used for controlling the target vehicle to stop accelerating by releasing the accelerator pedal according to the prompt sound or prompt light triggered by the last reflector (reflector 8-5) when the reference point of the target vehicle passes the last reflector (reflector 8-5) of the plurality of reflectors if the reference point is not at the rear end of the target vehicle (the reference point is at the front end or middle of the vehicle).

[0285] The release module 40 of this embodiment takes into account the fact that the reference point may be located at different positions of the vehicle (rear end, front end or middle part), and designs different trigger points accordingly. This design enables the test method to be flexibly applied to various vehicle models without making major adjustments due to different vehicle configurations.

[0286] In one embodiment, the processing module 50 includes a data unit and a processing unit, wherein the data unit is a process of obtaining the vehicle vibration and noise characteristic data, and the processing unit is a process of performing data processing on the vehicle vibration and noise characteristic data, specifically:

[0287] The data unit is used to press the start button of the data collector about 2 seconds before the reference point passes the reflector 8-1 to start collecting data, and press the end button of the data collector about 2 seconds after releasing the accelerator pedal to end data collection; the screen of the data collector can be operated blindly without distracting the driver's attention, and the test can also be completed by two people, one person driving the vehicle and the other person operating the data collector to collect data;

[0288] The data unit is also used to repeat the test and data collection on the test road surface in the above-mentioned manner, and synchronously collect the on-vehicle wired signal and the ground wireless signal of the target vehicle when the target vehicle is tested on the test road surface according to the data collector placed in the target vehicle, so as to obtain the vehicle vibration and noise characteristic data of the target vehicle after several tests; wherein the number of tests is preferably 4 times, and the number of repeated measurements can be determined according to the requirements of each region.

[0289] In addition, the wired signal on the vehicle and the wireless signal on the ground include a sound pressure simulation signal, and the specific method of obtaining the sound pressure simulation signal is as follows:

[0290] Arrange a number of noise measurement points on the test road surface; wherein the number of noise measurement points include vehicle exterior passing noise measurement points or vehicle exterior pedestrian warning sound measurement points arranged according to different test regulations;

[0291] The weak sound pressure signal collected by the microphone is amplified by the preamplifier, the amplified signal is conditioned into a standard analog signal by the signal conditioning device, and the conditioned standard analog signal is transmitted to the signal transmitting device; wherein the weak sound pressure signal is a sound pressure signal measured by a target vehicle passing through a plurality of noise measuring points when the target vehicle is tested on a test road surface;

[0292] After the standard analog signal is converted into a modulated signal suitable for wireless transmission by a signal transmitting device, it is sent to a signal receiving device for demodulation, and the sound pressure analog signal obtained after the signal demodulation is collected by a data collector;

[0293] Each group of signal transmitting devices and signal receiving devices is provided with a different carrier frequency; and the devices involved in data collection are all devices in the first integrated measurement system or the second integrated measurement system.

[0294] The data unit of this embodiment can flexibly choose to arrange the vehicle passing noise measurement points or the vehicle pedestrian warning sound measurement points according to different test regulations by arranging multiple noise measurement points on the test road surface to meet different test requirements. The weak sound pressure signal collected by the microphone is amplified by a preamplifier, and the amplified signal is conditioned into a standard analog signal by a signal conditioning device, which improves the stability and accuracy of the signal and is beneficial to subsequent fault diagnosis and analysis. The standard analog signal is converted into a modulated signal suitable for wireless transmission by a signal transmitting device, and sent to a signal receiving device for demodulation, thereby realizing wireless transmission of the signal and avoiding the wiring complexity and limitations that may be caused by wired transmission. In addition, each group of signal transmitting devices and signal receiving devices is provided with different carrier frequencies, which can effectively avoid signal interference between different measuring points and ensure accurate transmission and reception of data.

[0295] A processing unit, used for performing spectrum analysis on the ground wireless signal to obtain spectrum analysis results;

[0296] The processing unit is also used to perform fault diagnosis on the target vehicle based on the spectrum analysis results.

[0297] The processing unit is also used to observe and record relevant values ​​of the vehicle vibration and noise characteristic data based on a portable computer and data acquisition and analysis, control and display software 11, including but not limited to the voltage value of the photoelectric sensor, the opening of the driving pedal, the vehicle speed, the engine speed, the motor speed, the sound pressure level of the measuring point inside the vehicle, the acceleration of the measuring point inside the vehicle, and the sound pressure level of the measuring points on the left and right sides outside the vehicle, etc. These data will show different trends over time;

[0298] The processing unit is also used to integrate the vehicle speed data while observing the data to obtain the displacement information of the vehicle; and obtain the analysis data processed by the portable computer and the data acquisition and analysis, control and display software 11;

[0299] The processing unit is also used to eliminate unqualified data in the analysis data. If the number of measurements of the data after the data is eliminated does not meet the preset standard, the above test is repeated until the number of measurements of qualified data meets the preset standard;

[0300] The processing unit is also used to perform in-depth analysis (such as FFT analysis, time-frequency analysis, order analysis, etc.) of the acceleration signals and sound pressure signals of the measuring points inside the vehicle and the sound pressure signals of the measuring points outside the vehicle based on the analysis data that meets the preset standards, using professional data processing and analysis software, such as Test.Lab, Artemis or other equivalent analysis tools, so as to determine the main sources and causes of the vibration noise.

[0301] In the processing unit of this embodiment, spectrum analysis can quickly capture abnormal characteristics of signals, such as frequency offset, signal attenuation, etc., thereby shortening the time of fault diagnosis and improving diagnosis efficiency, so that faults or abnormalities in the target vehicle can be accurately located.

[0302] To apply the embodiments of this application, please refer to Figure 5-7 , Figure 5 This is a schematic diagram of the test data of accelerating through the measurement site according to GB1495-2002 provided in the embodiment of the present application, which shows the data obtained by accelerating through the measurement site test according to GB1495-2002 based on the measurement scheme of Example 2, specifically:

[0303] According to the GB1495-2002 standard, a number of dynamic parameters of a vehicle are recorded in detail while it is accelerating through the measurement site, including the voltage signal triggered by the reflector, the accelerator pedal opening, the vehicle speed, the displacement of the vehicle relative to the site, the sound pressure level inside and outside the vehicle, etc. All parameters are monitored over time.

[0304] Data analysis shows that the vehicle acceleration process starts when the reference point is 12.6 meters away from the AA' line. At this time, the driver presses the accelerator pedal and the vehicle enters the test area at a speed of 50.8 km / h at full throttle. As the acceleration progresses, when the reference point passes the midpoint PP' line, the vehicle speed reaches 56.6 km / h; the acceleration continues until the reference point passes the BB' line, and the vehicle speed has increased to 61.8 km / h. However, the acceleration process does not end immediately when the reference point passes the BB' line, but is delayed by 9.2 meters, that is, the driver releases the accelerator pedal 9.2 meters after the reference point passes the BB' line.

[0305] During the acceleration of the vehicle, the maximum sound pressure level measured at a distance of 7.5 meters from the left side of the vehicle is 70.9dBA, and this peak value corresponds to the moment when the reference point passes through the BB' line. Considering that the total length of the test vehicle is 5.2 meters and the reference point is set at the front end of the vehicle, it can be judged that the position where the driver releases the accelerator pedal in this measurement is about 4 meters later than the ideal state, which does not meet the requirements of regulatory standards and may cause the measured maximum sound pressure level value to be too high.

[0306] and, Figure 5 The relative displacement data of the vehicle to the site is obtained by integrating the vehicle speed data, and the rest of the data are measured by sensors and data collectors. In addition, the vehicle speed data can be differentiated to obtain the acceleration value at each moment during the test, and the average acceleration of each section of the interval can be calculated based on the relationship between displacement, speed, and acceleration to determine whether it meets the standard requirements.

[0307] Figure 6This is a table showing the test data of the accelerated passing measurement site according to ECE R51.03 provided in the embodiment of the present application, which shows the data obtained by the accelerated passing measurement site test according to ECE R51.03 based on the measurement scheme of the second embodiment;

[0308] like Figure 6 As shown in the figure, a series of key performance parameters recorded by a hybrid vehicle with a non-lockable gear in the process of accelerating through the measurement site in accordance with the ECE R51.03 standard are shown. Specifically, they include: the sound pressure level at 7.5 meters outside the vehicle, the vehicle speed at each measurement point, the average acceleration within the interval, the deviation between each acceleration and the four average accelerations, and the engine speed at each measurement point. It is worth noting that the acceleration values ​​listed in the chart are all obtained through precise calculations based on the mathematical relationship between displacement, speed and acceleration.

[0309] Figure 7 The spectrum diagram of the sound pressure level inside the vehicle and the sound pressure level outside the vehicle provided by the curve data of the embodiment of the present application shows Figure 6 The corresponding comparison of the noise spectra inside and outside the car measured simultaneously; Figure 7 It can be seen that the noise outside the car is mainly concentrated in the frequency band of 1000 Hz to 1200 Hz, which is mainly contributed by tire radiation noise.

[0310] To apply the embodiments of this application, please refer to Figure 8-9 , Figure 8 : is a comparison diagram of wireless signal and wired signal delays in different solutions provided in the embodiments of the present application, showing the comparison of wireless signal and wired signal delays under different solutions, specifically:

[0311] In a static test environment, a 100Hz sine wave signal is transmitted to the data collector via a wired transmission path and two different wireless transmission schemes (equipped with their own signal transceiver and conditioning devices). Subsequently, the time domain waveforms obtained by these transmission schemes are compared and analyzed. In the figure, the solid line represents the wired transmission signal, and the dotted line and dash-dot line represent the signals of the two wireless transmission schemes respectively;

[0312] The observation results show that both wireless transmission schemes have a certain signal delay compared to wired transmission, ranging from 1 millisecond to 3 milliseconds. Nevertheless, this delay level still meets the established usage requirements and ensures the effectiveness and accuracy of data transmission.

[0313] Fig. 9 : is a comparison diagram of wireless signal and wired signal spectra in different schemes provided in the embodiments of the present application, which shows the comparison of wireless signal and wired signal spectra in different schemes, specifically:

[0314] Under static test conditions, the sound pressure signal of a microphone is transmitted to the data collector through a wired transmission path and three different wireless transmission schemes (each equipped with a signal transceiver and conditioning device), and the FFT frequency domain waveforms obtained by these transmission paths are compared and analyzed. In the figure, the solid line represents the frequency domain waveform of the wired transmission signal, and the long dashed line, short dashed line and dotted line correspond to the frequency domain waveforms of the three wireless transmission schemes.

[0315] By observing the comparison results, it can be found that within the frequency range of 30Hz to 10kHz, the frequency domain waveforms of the three wireless transmission schemes are basically consistent with the frequency domain waveforms of the wired transmission scheme, showing a high degree of overlap. Further analysis shows that the maximum difference between the weighted total sound pressure level of wireless scheme A and the wired signal data is only 0.16dBA. This tiny difference fully meets the established usage requirements and verifies the accuracy and reliability of the wireless transmission scheme in sound pressure signal transmission.

[0316] Overall, this embodiment has the following beneficial effects:

[0317] This application sets clear test steps, including driving at a constant speed, accelerating, driving at a preset speed, and stopping acceleration. These standardized test processes help ensure the consistency of each test, making it easier to compare and analyze different test data. Among them, by accurately controlling the driving path and speed of the target vehicle on the test road, the operational complexity and time consumption caused by the numerous components in the traditional measurement method are reduced. The combination of the reflector and the prompt sound makes the test process more concise and clear, thereby improving the measurement efficiency. In addition, the driving state of the vehicle is controlled according to the prompt sound triggered by the reflector, which can achieve flexible adjustment under different test requirements and regulatory requirements. This flexibility allows the method to adapt to a variety of standards and test items. In addition, through the prompt sound triggered by the reflector, the driver can accurately know when to step on and release the accelerator pedal. This precise control reduces the error caused by improper operation of the driver and helps to improve the accuracy of the measurement data.

[0318] In summary, the present application can solve the problem of low measurement efficiency caused by the large number of components in the traditional measurement method by simplifying the component structure; by flexibly adjusting the position of the reflector, it can meet the needs of various standards and test items, and solve the problem that the fixed position of the reflector is difficult to meet the diverse requirements of regulations; and, by accurately prompting the driver's operation, it can solve the problem of low measurement accuracy caused by the traditional method's inability to accurately indicate the specific time and position of the driver's pressing and releasing the accelerator pedal.

[0319] Embodiment three:

[0320] An embodiment of the present application provides a computer-readable storage medium, wherein the computer-readable storage medium includes a stored computer program, wherein when the computer program is executed, the device where the computer-readable storage medium is located is controlled to execute the method for measuring vehicle vibration and noise characteristic data;

[0321] Wherein, the method for measuring vehicle vibration and noise characteristic data, if implemented in the form of a software functional unit and used as an independent product, can be stored in a computer-readable storage medium. Based on such an understanding, the present invention implements all or part of the processes in the above-mentioned embodiment method, and can also be completed by instructing the relevant hardware through a computer program. The computer program can be stored in a computer-readable storage medium, and the computer program can implement the steps of the above-mentioned various method embodiments when executed by the processor. Wherein, the computer program includes computer program code, and the computer program code can be in source code form, object code form, executable file or some intermediate form, etc. The computer-readable medium can include: any entity or device capable of carrying the computer program code, recording medium, U disk, mobile hard disk, magnetic disk, optical disk, computer memory, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), electric carrier signal, telecommunication signal and software distribution medium, etc.

[0322] The above are preferred embodiments of the present invention. It should be noted that, for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present invention. These improvements and modifications are also considered to be within the scope of protection of the present invention.

Claims

1. A method for measuring vehicle vibration and noise characteristic data, characterized in that: include: Controlling the target vehicle to travel at a constant speed on a test road surface passing by a first reflector; wherein the test road surface is provided with a plurality of reflectors distributed along the center line of the road surface; According to the prompt sound triggered by the first reflector, the target vehicle is controlled to accelerate and drive past the second reflector; According to the prompt sound triggered by the second reflector, the target vehicle is controlled to drive past the third reflector at a preset speed; According to the prompt sound triggered by the third reflector, controlling the target vehicle to stop accelerating; The vehicle vibration and noise characteristic data of the target vehicle are obtained by synchronously collecting the on-vehicle wired signal and the ground wireless signal of the target vehicle when the target vehicle is tested on the test road surface according to the data collector placed in the target vehicle.

2. A method for measuring vehicle vibration and noise characteristic data as claimed in claim 1, characterized in that: Control the target vehicle to drive at a constant speed on the test road surface past the first reflector, specifically: Installing a photoelectric sensor at a preset reference point of the target vehicle; Adjusting the plurality of reflective plates so that the photoelectric sensor can trigger sensing according to the reflected light of the plurality of reflective plates to output a high level; On the test road surface, the target vehicle is controlled to travel at a constant speed according to a preset speed until it passes the first reflector.

3. A method for measuring vehicle vibration and noise characteristic data as claimed in claim 2, characterized in that: According to the prompt sound triggered by the first reflector, the target vehicle is controlled to accelerate and drive past the second reflector, specifically: When the reference point of the target vehicle passes through the first reflector, according to the prompt sound triggered by the first reflector, the target vehicle is controlled to accelerate and pass through the second reflector; The prompt sound is obtained when the photoelectric sensor outputs a high-level signal according to the reflected light received from the first reflector, and triggers the prompt sound module of the target vehicle to play the prompt sound based on the output duration of the high-level signal.

4. A method for measuring vehicle vibration and noise characteristic data as claimed in claim 2, characterized in that: According to the prompt sound triggered by the third reflector, the target vehicle is controlled to stop accelerating, specifically: If the reference point is at the rear end of the target vehicle, when the reference point of the target vehicle passes the second to last reflector of the plurality of reflectors, the target vehicle is controlled to stop accelerating according to a prompt sound triggered by the second to last reflector; If the reference point is not at the rear end of the target vehicle, when the reference point of the target vehicle passes the last reflector of the plurality of reflectors, the target vehicle is controlled to stop accelerating according to a prompt sound triggered by the last reflector.

5. A method for measuring vehicle vibration and noise characteristic data as claimed in claim 3, characterized in that: The test road surface is provided with a number of reflectors distributed along the center line of the road surface, specifically: Five reflectors are arranged at the center line of the test road surface along the direction of vehicle travel; Among them, the placement positions of the five reflectors are symmetrical about the test section of the test road surface. If the target vehicle needs to perform an entry-line test from both ends of the test section, an auxiliary reflector is added behind the second reflector at the preset end of the test section to identify the driving direction of the target vehicle.

6. A method for measuring vehicle vibration and noise characteristic data as claimed in claim 1, characterized in that: The on-vehicle wired signal and the on-ground wireless signal include a sound pressure simulation signal, which is acquired based on a plurality of noise measurement points, specifically: Arranging the plurality of noise measuring points on the test road surface; wherein the plurality of noise measuring points include vehicle exterior passing noise measuring points or vehicle exterior pedestrian warning sound measuring points arranged according to different test regulations; A weak sound pressure signal collected by the microphone is amplified by a preamplifier, the amplified signal is conditioned into a standard analog signal by a signal conditioning device, and the conditioned standard analog signal is transmitted to a signal transmitting device; wherein the weak sound pressure signal is a sound pressure signal measured when the target vehicle passes through the plurality of noise measuring points when being tested on the test road surface; After the signal transmitting device converts the standard analog signal into a modulated signal suitable for wireless transmission, the signal is sent to a signal receiving device for demodulation, and the sound pressure analog signal obtained after signal demodulation is collected by the data collector; Each group of signal transmitting devices and signal receiving devices is provided with a different carrier frequency.

7. A method for measuring vehicle vibration and noise characteristic data as claimed in claim 1, characterized in that: After obtaining the vehicle vibration and noise characteristic data of the target vehicle, the method further includes: Performing spectrum analysis on the ground wireless signal to obtain spectrum analysis results; Fault diagnosis is performed on the target vehicle according to the spectrum analysis result.

8. A device for measuring vehicle vibration and noise characteristic data, characterized in that: It includes a constant speed module, an acceleration module, a control module, a release module and a processing module; The constant speed module is used to control the target vehicle to travel at a constant speed on the test road surface and pass the first reflector; wherein the test road surface is provided with a plurality of reflectors distributed along the center line of the road surface; The acceleration module is used to control the target vehicle to accelerate and drive past the second reflector according to the prompt sound triggered by the first reflector; The control module is used to control the target vehicle to drive past the third reflector at a preset speed according to the prompt sound triggered by the second reflector; The release module is used to control the target vehicle to stop accelerating according to the prompt sound triggered by the third reflector; The processing module is used to synchronously collect the on-vehicle wired signals and the ground wireless signals of the target vehicle when the target vehicle is tested on the test road surface according to the data collector placed in the target vehicle, so as to obtain the vehicle vibration and noise characteristic data of the target vehicle.

9. A device for measuring vehicle vibration and noise characteristic data as claimed in claim 8, characterized in that: The constant speed module includes an installation unit, an adjustment unit and a constant speed unit; Wherein, the installation unit is used to install a photoelectric sensor at a preset reference point of the target vehicle; The adjustment unit is used to adjust the plurality of reflective plates so that the photoelectric sensor can trigger sensing according to the reflected light of the plurality of reflective plates to output a high level; The constant speed unit is used to control the target vehicle to travel at a constant speed at a preset speed on the test road surface until it passes the first reflector.

10. The device for measuring vehicle vibration and noise characteristic data according to claim 9, characterized in that: The acceleration module includes an acceleration unit; Wherein, the acceleration unit is used to control the target vehicle to accelerate and pass through the second reflector according to the prompt sound triggered by the first reflector when the reference point of the target vehicle passes through the first reflector; The prompt sound is obtained when the photoelectric sensor outputs a high-level signal according to the reflected light received from the first reflector, and triggers the prompt sound module of the target vehicle to play the prompt sound based on the output duration of the high-level signal.

11. The device for measuring vehicle vibration and noise characteristic data according to claim 9, characterized in that: The release module tail unit and trigger unit; Wherein, the tail end unit is used to control the target vehicle to stop accelerating according to the prompt sound triggered by the penultimate reflector when the reference point of the target vehicle passes through the penultimate reflector of the plurality of reflectors if the reference point is at the tail end of the target vehicle; The trigger unit is used to control the target vehicle to stop accelerating according to the prompt sound triggered by the last-to-last reflector when the reference point of the target vehicle passes through the last-to-last reflector of the plurality of reflectors if the reference point is not at the rear end of the target vehicle.

12. The device for measuring vehicle vibration and noise characteristic data according to claim 10, characterized in that: The test road surface is provided with a number of reflectors distributed along the center line of the road surface, specifically: Five reflectors are arranged at the center line of the test road surface along the direction of vehicle travel; Among them, the placement positions of the five reflectors are symmetrical about the test section of the test road surface. If the target vehicle needs to perform an entry-line test from both ends of the test section, an auxiliary reflector is added behind the second reflector at the preset end of the test section to identify the driving direction of the target vehicle.

13. The device for measuring vehicle vibration and noise characteristic data according to claim 8, characterized in that: The on-vehicle wired signal and the on-ground wireless signal include a sound pressure simulation signal, which is acquired based on a plurality of noise measurement points, specifically: Arranging the plurality of noise measuring points on the test road surface; wherein the plurality of noise measuring points include an external vehicle passing noise measuring point or an external vehicle pedestrian warning sound measuring point; A weak sound pressure signal collected by the microphone is amplified by a preamplifier, the amplified signal is conditioned into a standard analog signal by a signal conditioning device, and the conditioned standard analog signal is transmitted to a signal transmitting device; wherein the weak sound pressure signal is a sound pressure signal measured when the target vehicle passes through the plurality of noise measuring points when being tested on the test road surface; After the signal transmitting device converts the standard analog signal into a modulated signal suitable for wireless transmission, the signal is sent to a signal receiving device for demodulation, and the sound pressure analog signal obtained after signal demodulation is collected by the data collector; Each group of signal transmitting devices and signal receiving devices is provided with a different carrier frequency.

14. The device for measuring vehicle vibration and noise characteristic data according to claim 8, characterized in that: After obtaining the vehicle vibration and noise characteristic data of the target vehicle, the method further includes: Performing spectrum analysis on the ground wireless signal to obtain spectrum analysis results; Fault diagnosis is performed on the target vehicle according to the spectrum analysis result.

15. A storage medium, characterized in that: The storage medium stores a computer program, which is called and executed by a computer to implement a method for measuring vehicle vibration and noise characteristic data as described in any one of claims 1 to 7.

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