Method and device for testing dynamic characteristics of air suspension system

Abstract

The application provides a kind of air suspension system dynamic characteristic test method and device, comprising: adjusting air suspension system to equilibrium position, the air suspension system includes air spring;According to the preset excitation parameter, using the dynamometer test platform of pre-built to the air spring dynamometer test, to obtain dynamometer test result;Utilize the quarter bench test platform of pre-built to the air spring quarter bench test, to obtain quarter bench test result;According to the dynamometer test result, the quarter bench test result and preset formula, the dynamic characteristic of the air spring is calculated and obtained.The application gives the test method for the dynamic characteristic of air spring, including dynamometer test and quarter bench test, realizes the test of more efficient, better expandability air spring.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of vehicle manufacturing, in particular to a dynamic characteristic test method and device of an air suspension system. BACKGROUND

[0002] Air springs have been widely concerned and applied in the fields of vehicles and precision vibration isolation due to their excellent vibration isolation performance. For passenger cars, air springs have the advantages of adjustable height, improved smoothness, lighter weight, and effective noise suppression. With the increasing requirement for vehicle comfort, the dynamic characteristic data of air springs are crucial in vehicle design and overall performance optimization.

[0003] In the prior art, most air spring test methods are for testing the static stiffness and fatigue performance of air springs, or only for testing the dynamic response of the suspension itself in suspension bench performance tests, which have the problems of low efficiency and poor scalability. SUMMARY

[0004] The present application provides a dynamic characteristic test method and device of an air suspension system to solve the defects of low efficiency and poor scalability in the prior art, and to achieve higher efficiency and better scalability.

[0005] The present application provides a dynamic characteristic test method of an air suspension system, comprising:

[0006] adjusting the air suspension system to an equilibrium position, the air suspension system comprising an air spring;

[0007] performing a dynamometer test on the air spring using a pre-built dynamometer test platform according to preset excitation parameters to obtain a dynamometer test result;

[0008] performing a quarter bench test on the air spring using a pre-built quarter bench test platform to obtain a quarter bench test result;

[0009] calculating the dynamic characteristics of the air spring according to the dynamometer test result, the quarter bench test result, and a preset formula.

[0010] According to the dynamic characteristic test method of the air suspension system provided by the present application, the preset excitation parameters include amplitude and frequency, each amplitude is tested at all frequencies, each group of tests is continuously performed for a preset number of cycle excitations, and at least a preset time interval is provided between adjacent groups of tests.

[0011] According to the dynamic characteristic test method of the air suspension system provided by the present application, the quarter bench test on the air spring is performed using a pre-built quarter bench test platform to obtain a quarter bench test result, which specifically comprises:

[0012] Obtain the on-spring acceleration of the air spring by using an on-spring acceleration sensor, which is installed above the air spring;

[0013] Obtain the off-spring acceleration of the air spring by using an off-spring acceleration sensor, which is installed below the air spring;

[0014] Obtain the exciting acceleration of the air spring by using an exciting acceleration sensor, which is installed at the bottom of the slide rail;

[0015] Obtain the stroke of the air spring by using a stroke sensor, which is installed at the side of the air spring.

[0016] According to the present application, a dynamic characteristic testing method of an air suspension system is provided, and the dynamic characteristic of the air spring is calculated according to the dynamometer test result, the quarter-dynamometer test result and a preset formula, specifically including:

[0017] According to a first preset formula, the frequency correlation of the air spring is calculated;

[0018] The first preset formula includes:

[0019]

[0020]

[0021]

[0022] Wherein, K(ω) is the total stiffness; k A is the effective area stiffness; k1 is the high-pressure gas stiffness; c1 is the equivalent damping of gas heat exchange; j is the imaginary unit; ω is the exciting frequency; γ is the specific heat capacity ratio; p b0 is the initial pressure; A eff is the effective area; V b0 is the effective volume; C V is the specific heat capacity at constant volume; m b0 is the initial gas mass; K b is the heat exchange coefficient; p b is the gas pressure in the motion process; p atm is the atmospheric pressure; and z is the vertical displacement.

[0023] According to the present application, a dynamic characteristic testing method of an air suspension system is provided, and the dynamic characteristic of the air spring is calculated according to the dynamometer test result, the quarter-dynamometer test result and a preset formula, specifically including:

[0024] According to a second preset formula, the amplitude correlation of the air spring is calculated;

[0025] The second preset formula includes:

[0026]

[0027]

[0028]

[0029] Where K(ω) is the total stiffness; k Re k is the real part of the dynamic stiffness. Im K is the imaginary part of the dynamic stiffness; K′ is the real part of the dynamic stiffness of the rubber airbag; K″ is the imaginary part of the dynamic stiffness of the rubber airbag; A is the excitation amplitude; k A ω is the effective area stiffness; k1 is the high-pressure gas stiffness; c1 is the equivalent damping of gas heat exchange; ω is the excitation frequency; γ is the specific heat ratio; p b0 This is the initial pressure; A eff V represents the effective area. b0 For effective volume; C V Specific heat capacity at constant volume; m b0 K represents the initial gas mass. b p is the heat exchange coefficient. b p represents the gas pressure during motion. atm ρ represents the external atmospheric pressure; z represents the vertical displacement.

[0030] According to the present invention, a method for testing the dynamic characteristics of an air suspension system calculates the dynamic characteristics of the air spring based on the indicator test results, the quarter-bench test results, and a preset formula. Specifically, the method includes:

[0031] The transmission characteristics of the air spring are calculated according to the third preset formula;

[0032] The third preset formula includes:

[0033]

[0034] in, for arrive The transfer function; for and The cross-correlation function; for The autocorrelation function; The Fourier transform of the spring acceleration; Fourier transform (transpose) of the excitation input; Fourier transform of the excitation input.

[0035] The application further provides an air suspension system dynamic characteristic testing device.

[0036] An adjusting unit is configured to adjust the air suspension system to a balanced position, wherein the air suspension system comprises an air spring.

[0037] A testing unit is configured to perform a dynamometer test on the air spring by using a pre-built dynamometer test platform according to preset excitation parameters, so as to obtain a dynamometer test result.

[0038] A quarter bench test is performed on the air spring by using a pre-built quarter bench test platform, so as to obtain a quarter bench test result.

[0039] A calculating unit is configured to calculate the dynamic characteristic of the air spring according to the dynamometer test result, the quarter bench test result and a preset formula.

[0040] The application further provides an electronic device, which comprises a memory, a processor and a computer program stored in the memory and executable on the processor, wherein the processor implements the air suspension system dynamic characteristic testing method according to any one of the above-mentioned methods when executing the program.

[0041] The application further provides a non-transitory computer readable storage medium, which stores a computer program, wherein the computer program is executable on a processor to implement the air suspension system dynamic characteristic testing method according to any one of the above-mentioned methods.

[0042] The application further provides a computer program product, which comprises a computer program, wherein the computer program is executable on a processor to implement the air suspension system dynamic characteristic testing method according to any one of the above-mentioned methods.

[0043] The air suspension system dynamic characteristic testing method and device provided by the application adjust the air suspension system to a balanced position, wherein the air suspension system comprises an air spring; perform a dynamometer test on the air spring by using a pre-built dynamometer test platform according to preset excitation parameters, so as to obtain a dynamometer test result; perform a quarter bench test on the air spring by using a pre-built quarter bench test platform, so as to obtain a quarter bench test result; and calculate the dynamic characteristic of the air spring according to the dynamometer test result, the quarter bench test result and a preset formula. The application provides a testing method for the dynamic characteristic of the air spring, which comprises a dynamometer test and a quarter bench test, and the testing of the air spring is more efficient and has better expansibility. BRIEF DESCRIPTION OF DRAWINGS

[0044] In order to more clearly illustrate the technical solutions in the present application or the prior art, the accompanying drawings needed to be used in the embodiments or prior art description will be briefly introduced. Obviously, the accompanying drawings in the following description are only some embodiments of the present application, and for those skilled in the art, other drawings can also be obtained without creative effort.

[0045] Figure 1 is a flowchart of the air suspension system dynamic characteristic test method provided by the present application;

[0046] Figure 2 is a schematic diagram of the indicator diagram test flow of one embodiment of the air suspension system dynamic characteristic test method provided by the present application;

[0047] Figure 3 is a schematic diagram of the rear axle air spring indicator diagram hysteresis curve of one embodiment of the air suspension system dynamic characteristic test method provided by the present application;

[0048] Figure 4 is a schematic diagram of the front axle air spring indicator diagram hysteresis curve of one embodiment of the air suspension system dynamic characteristic test method provided by the present application;

[0049] Figure 5 is a comparison diagram of the large-stroke gas frequency characteristic test theoretical value and test value of one embodiment of the air suspension system dynamic characteristic test method provided by the present application;

[0050] Figure 6 is a comparison diagram of the small-stroke bag skin dynamic stiffness test theoretical value and test value of one embodiment of the air suspension system dynamic characteristic test method provided by the present application;

[0051] Figure 7 is a schematic diagram of the sensor setting of the air suspension system dynamic characteristic test method provided by the present application;

[0052] Figure 8 is a comparison diagram of the frequency sweep test amplitude and phase characteristics of the quarter-dynamic test of one embodiment of the air suspension system dynamic characteristic test method provided by the present application;

[0053] Figure 9 is a structural schematic diagram of the air suspension system dynamic characteristic test device provided by the present application;

[0054] Figure 10 is a structural schematic diagram of the electronic device provided by the present application.

[0055] Reference signs:

[0056] 910: adjustment unit; 920: test unit; 930: calculation unit;

[0057] 1010: processor; 1020: communication interface; 1030: memory; 1040: communication bus. DETAILED DESCRIPTION

[0058] To make the objectives, technical solutions, and advantages of the present application clearer, the technical solutions in the present application will be described clearly and completely below with reference to the drawings in the present application. Obviously, the described embodiments are some, but not all, of the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative work fall within the protection scope of the present application.

[0059] The present application provides an air suspension system dynamic characteristic test method, Figures 1-8 The present application provides an air suspension system dynamic characteristic test method, Figure 1 is a flowchart of the air suspension system dynamic characteristic test method provided by the present application, as Figure 1 The present application provides an air suspension system dynamic characteristic test method, which comprises the following steps.

[0060] Step 110: adjusting the air suspension system to an equilibrium position, wherein the air suspension system comprises an air spring.

[0061] Before testing the air suspension, the air suspension needs to be adjusted to an equilibrium position. The main purpose of adjusting the air suspension to the equilibrium position is to exclude the influence of other factors on the test. The method of adjusting the air suspension to the equilibrium position comprises adjusting the air suspension to the equilibrium position by using a control computer. The air suspension involved in the present application comprises an air spring.

[0062] Step 120: performing a dynamometer test on the air spring by using a pre-built dynamometer test platform according to preset excitation parameters, to obtain a dynamometer test result.

[0063] performing a quarter bench test on the air spring by using a pre-built quarter bench test platform, to obtain a quarter bench test result.

[0064] After adjusting the air suspension to the equilibrium position, the test on the air spring is started, and the test comprises a dynamometer test and a quarter bench test.

[0065] The dynamometer test is completed by using the pre-built dynamometer test platform, and the purpose is to determine the characteristics of the air spring, specifically including determining the amplitude correlation and frequency correlation of the air spring. The frequency correlation is mainly generated by the heat exchange and stiffness of the gas inside the air spring; and the amplitude correlation is mainly caused by the Payne effect of the elastomeric skin of the air spring. The dynamometer test mainly comprises two parts of a large-stroke gas frequency characteristic test and a small-stroke skin dynamic stiffness test.

[0066] In actual operation, when the large-stroke gas frequency characteristic test is performed, after being adjusted to the equilibrium position (equilibrium height and internal pressure), a sinusoidal excitation dynamometer test can be performed. Assuming that the maximum stroke of the air spring is S w (wherein S is the stroke rather than the amplitude), the excitation parameters of the dynamometer test are specifically valued according to the preset, so as to obtain a test result, which can be represented as an air spring dynamometer hysteresis curve.

[0067] In actual operation, when the small-stroke bladder skin dynamic stiffness test is performed, after being adjusted to the equilibrium position (equilibrium height and internal pressure), assuming that the maximum stroke of the air spring is S w (wherein S is the stroke rather than the amplitude), the excitation parameters are specifically valued according to the preset, so as to obtain a test result. Since the small-stroke bladder skin dynamic stiffness test mainly reflects the Payne effect dynamic stiffness characteristics of the air spring bladder skin, it needs to be performed under small amplitude.

[0068] The quarter bench test is completed by using a pre-built quarter bench test platform, and the purpose is to verify the transmission characteristics of the air spring, specifically including verifying the frequency transmission characteristics and amplitude transmission characteristics of the air suspension system. Specifically, by using different sprung masses and test conditions, the dynamic characteristics of the air spring are determined and guidance is provided for vehicle calibration and dynamics matching. The quarter bench test is mainly a harmonic excitation test.

[0069] In actual operation, after being adjusted to the equilibrium position, the excitation parameters are specifically valued according to the preset, so as to obtain a test result.

[0070] Step 130: According to the dynamometer test result, the quarter bench test result and a preset formula, the dynamic characteristics of the air spring are calculated.

[0071] After obtaining the test result, the dynamic characteristics of the air spring are calculated according to the preset formula.

[0072] Based on the above embodiment, in the method, the preset excitation parameters include an amplitude and a frequency, each amplitude is subjected to all frequency tests, each group of tests (fixed frequency and fixed amplitude) is continuously subjected to, for example, 3 cyclic excitations, and adjacent groups of tests are at least separated by, for example, 5 seconds.

[0073] Specifically, the preset excitation parameters include an amplitude and a frequency, each amplitude is subjected to all frequency tests, each group of tests (fixed frequency and fixed amplitude) is continuously subjected to, for example, 3 cyclic excitations, and adjacent groups of tests are at least separated by, for example, 5 seconds.

[0074] Based on the above embodiment, in the method, according to the dynamometer test result, the quarter bench test result and a preset formula, the dynamic characteristics of the air spring are calculated, specifically including:

[0075] According to a first preset formula, the frequency correlation of the air spring is calculated.

[0076] The first preset formula comprises:

[0077]

[0078]

[0079]

[0080] K (ω) is total stiffness; k A is effective area stiffness; k1 is high-pressure gas stiffness; c1 is gas heat exchange equivalent damping; j is imaginary unit; ω is excitation frequency; γ is specific heat capacity ratio; p b0 is initial pressure; A eff is effective area; V b0 is effective volume; C V is specific heat capacity at constant volume; m b0 is initial gas mass; K b is heat exchange coefficient; p b is gas pressure in the motion process; p atm is atmospheric pressure; and z is vertical displacement.

[0081] Based on the above embodiment, in the method, the dynamic characteristics of the air spring are calculated according to the dynamometer test result, the quarter-drum test result and a preset formula, and specifically comprising:

[0082] According to a second preset formula, the amplitude correlation of the air spring is calculated.

[0083] The second preset formula comprises:

[0084]

[0085]

[0086]

[0087] K (ω) is total stiffness; k Re is dynamic stiffness real part; k Im is dynamic stiffness imaginary part; K' is dynamic stiffness real part of the rubber air bag; K'' is dynamic stiffness imaginary part of the rubber air bag; A is excitation amplitude; k A is effective area stiffness; k1 is high-pressure gas stiffness; c1 is gas heat exchange equivalent damping; ω is excitation frequency; γ is specific heat capacity ratio; p b0 is initial pressure; A eff is effective area; V b0 is effective volume; C VCv is the specific heat capacity at constant volume; m b0 K is the initial gas mass; K b K is the heat exchange coefficient; p b K is the gas pressure during movement; p atm K is the atmospheric pressure; z is the vertical displacement.

[0088] Specifically, the dynamometer test mainly includes two parts of large-stroke gas frequency characteristic test and small-stroke capsule skin dynamic stiffness test, and is completed by using a pre-built dynamometer test platform.

[0089] In an embodiment of the present application, the dynamometer test platform can adopt a test platform device of a Mechanical Testing & Simulation (MTS) company, including a dynamometer test bench (number MTS850.50) and a machine case (number PL5AA89F19C). The dynamometer test bench includes a force sensor, a vertical control rod, a hydraulic actuator, a vertical controller, a high-pressure gas pipe, a pressure reducing valve, a gas pressure gauge, a cooling control system, a cooling water pipe and the like.

[0090] As Figure 2 , Figure 2 A dynamometer test flow diagram is shown, high-pressure gas flows into the air spring from the gas source through the pipeline and the pressure reducing valve, the pressure gauge. After the charging and discharging are completed, the pipeline and the pipe length are constrained by using a binding belt. The final signal is obtained by the force sensor and the displacement sensor.

[0091] The installation of the air spring needs to consider the design of the upper and lower tooling, and mainly considers the concentric installation of the air spring to avoid that the transverse force borne by the air spring is too large to cause transverse deformation and thus damage the equipment and cause danger.

[0092] The height and internal pressure of the air spring are adjusted to reach the balance, and then the sinusoidal excitation dynamometer test can be performed. Assuming that the maximum stroke of the air spring is S w (here, the stroke instead of the amplitude), the excitation parameters of the sinusoidal dynamometer test are according to the preset excitation parameter values, and the excitation parameters include the amplitude and the frequency. Each amplitude is tested at all frequencies, each group of tests (fixed frequency and fixed amplitude) is continuously performed for a preset number of cycle excitations, and at least a preset time is interval between adjacent groups of tests. After the test is completed, the dynamometer test result is obtained. Wherein, the different air spring strokes are slightly different, and should be considered when the preset excitation parameters are considered.

[0093] The test result of the large-stroke gas frequency characteristic test can be expressed as an air spring dynamometer hysteresis curve. As Figure 3 and Figure 4 , Figure 3 is a rear air spring dynamometer hysteresis curve diagram of an embodiment of the dynamic characteristic test method of the air suspension system provided by the present application, Figure 4is a schematic diagram of a front axle air spring work done hysteresis curve of an embodiment of the air suspension system dynamic characteristic test method provided by the present application.

[0094] In one embodiment, for the large stroke gas frequency characteristic test of the rear axle air spring, the height and internal pressure of the air spring are adjusted to reach equilibrium, and then the sinusoidal excitation work done test is performed. Assuming that the maximum stroke of the air spring is S w (maximum stroke, not amplitude), the specific values of the excitation parameters of the sinusoidal work done test can refer to Table 1.

[0095] Table 1: Excitation parameter values of the sinusoidal work done test

[0096]

[0097] The schematic diagram of the work done hysteresis curve of the rear axle air spring is obtained, as shown in Figure 3 .

[0098] Each amplitude is tested at all frequencies, each group of tests (fixed frequency and amplitude) is continuously excited for 3 cycles, and adjacent groups of tests are at least 5 seconds apart. According to the work done test results, the theoretical value of the air spring hysteresis characteristic is calculated according to the first preset formula:

[0099]

[0100]

[0101]

[0102] wherein K(ω) is the total stiffness; k A is the effective area stiffness; k1 is the high-pressure gas stiffness; c1 is the equivalent damping of gas heat exchange; j is the imaginary unit; ω is the excitation frequency; γ is the specific heat capacity ratio; p b0 is the initial pressure; A eff is the effective area; V b0 is the effective volume; C V is the specific heat capacity at constant volume; m b0 is the initial gas mass; K b is the heat exchange coefficient; p b is the gas pressure during movement; p atm is the atmospheric pressure; and z is the vertical displacement.

[0103] The comparison between the test theoretical value and the test value of the first large stroke gas frequency characteristic test is shown in Figure 5 .

[0104] In another embodiment, the large stroke gas frequency characteristic test is performed on the front axle air spring. The test scheme of the front axle air suspension is the same as that of the rear axle, but in order to exclude the influence of the original shock absorber, a shock absorber tooling is needed to be installed to avoid the influence of damping. The shock absorber tooling is completely the same as the shape and internal structure of the shock absorber, and only shows constant friction characteristics in the dynamometer test. When performing the test, the designed shock absorber and air spring assembly need to be tested by the dynamometer, and the front axle air spring dynamometer hysteresis curve diagram is obtained as shown in FIG. 2. Figure 4 .

[0105] In another embodiment, the small stroke bladder skin dynamic stiffness test is performed on the air spring in two parts. The height and internal pressure of the air spring are adjusted to reach equilibrium, and then the sine excitation dynamometer test is performed. Assuming that the maximum stroke of the air spring is S w (herein the stroke rather than the amplitude), the excitation parameters of the sine dynamometer test can refer to Table 2 for specific values. Table 2 shows the test amplitude and frequency values under low amplitude.

[0106] Table 2: Sine dynamometer low amplitude test excitation parameter values

[0107] Amplitude A / mm Frequency f / Hz 0.1；0.2；0.5；0.8； 0.005；0.01；0.02；0.05； 1.0；2.0；5.0；8.0；10.0 0.08；0.1；1.0；5.0

[0108] Each amplitude is tested at all frequencies, each group of tests (fixed frequency and amplitude) is continuously excited for 3 cycles, and adjacent groups of tests are at least 5 seconds apart. According to the dynamometer test results, the theoretical value of the air spring hysteresis characteristic is calculated according to the second preset formula:

[0109]

[0110]

[0111]

[0112] Wherein, K(ω) is the total stiffness; k Re is the real part of the dynamic stiffness; k Im is the imaginary part of the dynamic stiffness; K' is the real part of the rubber air bag dynamic stiffness; K" is the imaginary part of the rubber air bag dynamic stiffness; A is the excitation amplitude; k A is the effective area stiffness; k1 is the high pressure gas stiffness; c1 is the equivalent damping of gas heat exchange; ω is the excitation frequency; γ is the specific heat capacity ratio; p b0 is the initial pressure; A eff is the effective area; V b0 is the effective volume; C V is the specific heat capacity at constant volume; m b0 is the initial gas mass; K b is the heat exchange coefficient; p b is the gas pressure during motion; p atmρ represents the external atmospheric pressure; z represents the vertical displacement.

[0113] A diagram showing the comparison between theoretical and experimental values ​​of dynamic stiffness of the skin during a short-stroke test is shown below. Figure 6 .

[0114] Based on the above embodiments, in this method, the air spring is subjected to a quarter-bench test using a pre-built quarter-bench test platform to obtain the quarter-bench test results, specifically including:

[0115] The on-spring acceleration of the air spring is obtained using an on-spring acceleration sensor, which is mounted above the air spring.

[0116] The unsprung acceleration of the air spring is obtained using an unsprung acceleration sensor, which is installed below the air spring.

[0117] The excitation acceleration of the air spring is obtained using an excitation acceleration sensor, which is installed at the bottom of the slide rail;

[0118] The stroke of the air spring is obtained using a stroke sensor, which is mounted on the side of the air spring.

[0119] Based on the above embodiments, the method calculates the dynamic characteristics of the air spring according to the dynamometer test results, the quarter-bench test results, and a preset formula, specifically including:

[0120] The transmission characteristics of the air spring are calculated according to the third preset formula;

[0121] The third preset formula includes:

[0122]

[0123] in, for arrive The transfer function; for and The cross-correlation function; for The autocorrelation function; The Fourier transform of the spring acceleration; Fourier transform (transpose) of the excitation input; Fourier transform of the excitation input.

[0124] Specifically, the quarter-bench test mainly consists of harmonic excitation tests. Harmonic excitation tests mainly include frequency sweep tests and fixed-frequency tests.

[0125] likeFigure 7 , Figure 7 is a sensor setting schematic diagram of a dynamic characteristic test method of an air suspension system provided by the present application, and the sensor comprises an on-spring acceleration sensor, an off-spring acceleration sensor, an exciting acceleration sensor and a stroke sensor. Using multiple motion sensors, kinematic information of all positions can be obtained through direct measurement or indirect calculation, all kinematic parameters can be directly measured on the same device, and subsequent data processing and transmission characteristic analysis are facilitated.

[0126] In the quarter bench test, the relevant momentum is measured by each sensor.

[0127] In some embodiments, the quarter bench test platform mainly relies on the mechanical test equipment (number MTS248.05) of MTS company. The sensor uses MTS (Mechanical Testing & Simulation) sensor. The MTS sensor can record vibration displacement, speed and acceleration information. The acceleration and displacement data in the test process are directly measured by the corresponding stroke and acceleration sensor. The sensor data is recorded in real time by the vehicle level high speed control prototype MicroAutoBox II (model MABX_II_1513 / C) manufactured by Germany dSPACE GmbH. MicroAutoBox II is a real-time system that can realize the bottommost layer of the upper layer algorithm. Combined with MATLAB / Simulink, user algorithms can be combined to perform hardware-in-the-loop simulation and other functions. It has rich input / output interfaces and can communicate with vehicle signals through CAN. After installing the real-time simulation system (Real-Time Interface, RTI) on the host computer, the RTI module interface can be opened using MATLAB commands. Users can select hardware modules according to hardware models, such as analog signal processing, digital signal processing, ECU module, CAN module, serial port module, etc. The corresponding module is dragged and dropped into Simulink, and combined with other programs for real-time input and output.

[0128] The sensors are set according to the measurement requirements to analyze the kinematic information and transmission characteristics of each position in the air suspension system through the acquired data. Specifically, the on-spring acceleration sensor is placed above the air spring to test the on-spring displacement, on-spring speed and on-spring acceleration; the off-spring acceleration sensor is connected to the hub below the air spring to test the vertical displacement, off-spring speed and off-spring position acceleration at the hub; the stroke sensor is installed on the side of the air spring, and the stroke sensor is connected to the lower fork arm through a long rod that can rotate around the fixed shaft of the stroke sensor, the long rod is fixed on the lower fork arm through a screw, and the long rod is parallel to the main shaft of the air spring, which is convenient for subsequent calculation of the stroke of the air suspension system. The excitation table includes a slide rail device, and the air suspension system is placed on the slide rail of the excitation table to release the lateral force of the tire during movement. The lower fork arm is used to ensure that the outside of the tire is parallel to the mass block plane during movement, so that the tire will horizontally translate when the tool is firmly connected during the vertical movement of the mass block. If this part of the translation and the influence on the vertical characteristics of the tire are not considered, the measurement data will not be accurate, and the lateral stiffness of the tire may damage the rack structure. In addition, an excitation acceleration sensor is installed at the bottom of the slide rail to measure the acceleration in the excitation table to prevent interference with the slide rail stroke. The mass block is used to prevent the movement of the slide rail and support the suspension in various balanced positions to improve scalability. The air tank and pressure reducing valve are used to introduce high pressure gas into the air spring.

[0129] In some embodiments, during actual operation, first start the MTS device, use the control computer to adjust the air suspension system to the balanced position, add weights on the mass block according to the preset design pressure and dynamometer test results to meet the test requirements. Then, during test preparation, according to the balanced position of the air spring, use the crane to lift the mass block, remove the protective wood block and steel block, introduce the high pressure gas in the air tank into the air spring through the pressure reducing valve, fill it, use the internally filled high pressure gas to lift the on-spring mass (mass block), allow the entire spring to be supported by the air spring valve only. During actual test, it is necessary to avoid the influence of the crane on the test, reduce the crane to ensure the mass, so that the crane does not interfere with the test, but still serves to limit and protect the entire mass block. Since the MTS software can directly measure the acceleration of the acceleration sensor, the acceleration of the acceleration sensor can be verified, and the true value of the acceleration sensor can be corrected to a certain extent.

[0130] During the test, after adjusting to the balanced position and setting is completed, the sweep test and the fixed frequency test are carried out. The excitation parameters of the sweep test and the fixed frequency test are according to the preset excitation parameter values, and the excitation parameters include amplitude and frequency. Each amplitude carries out all frequency tests, each group of tests (fixed frequency and fixed amplitude) continuously carries out a preset number of cycle excitations, and at least a preset time interval is provided between adjacent groups of tests. After the test is completed, the test results are obtained.

[0131] In some embodiments, the sweep test is an equal amplitude sweep from 0.005 Hz to 20 Hz with a fixed amplitude A = 0.1; 0.5; 1; 2; 5; 8; 10 mm at a frequency variation rate of 0.5 octave / s, n = 10 groups of tests are performed at each amplitude. The fixed frequency test adopts an amplitude of A = 0.1; 0.5; 1; 2; 5; 8; 10 mm, in order to accurately measure the system transfer characteristics near the resonance region, fixed frequency excitation at frequencies of f = 0.1; 0.5; 1; 1.3; 1.6; 2; 3; 4; 5 Hz is performed at each amplitude. Each test is performed n = 10 cycles, and the final steady-state response amplitude and phase are taken as the transfer characteristics of the system under the excitation to obtain the quarter bench test results.

[0132] According to the quarter bench test results, the transfer function is calculated based on a third preset formula:

[0133]

[0134] wherein, is the transfer function from x to y; is the cross-correlation function of x and y; is the autocorrelation function of x; is the Fourier transform of the sprung acceleration; is the Fourier transform (transpose) of the excitation input; is the Fourier transform of the excitation input. The amplitude and phase characteristics of the sweep test of a single quarter bench test are compared in the schematic view . In the above specific embodiments, the air suspension system dynamic characteristic test method provided by the present application adjusts the air suspension system to the equilibrium position, the air suspension system includes an air spring, according to the preset excitation parameters, the air spring is tested by using the pre-built dynamometer test platform to obtain the dynamometer test results, the air spring is tested by using the pre-built quarter bench test platform to obtain the quarter bench test results, and the dynamic characteristics of the air spring are calculated according to the dynamometer test results, the quarter bench test results and the preset formula. The present application gives the test method for the dynamic characteristics of the air spring including the dynamometer test and the quarter bench test, and realizes the test of the air spring with higher efficiency and better expansibility.

[0135] In the above specific embodiments, the air suspension system dynamic characteristic test method provided by the present application adjusts the air suspension system to the equilibrium position, the air suspension system includes an air spring, according to the preset excitation parameters, the air spring is tested by using the pre-built dynamometer test platform to obtain the dynamometer test results, the air spring is tested by using the pre-built quarter bench test platform to obtain the quarter bench test results, and the dynamic characteristics of the air spring are calculated according to the dynamometer test results, the quarter bench test results and the preset formula. The present application gives the test method for the dynamic characteristics of the air spring including the dynamometer test and the quarter bench test, and realizes the test of the air spring with higher efficiency and better expansibility. Figure 8

[0136] In the above specific embodiments, the air suspension system dynamic characteristic test method provided by the present application adjusts the air suspension system to the equilibrium position, the air suspension system includes an air spring, according to the preset excitation parameters, the air spring is tested by using the pre-built dynamometer test platform to obtain the dynamometer test results, the air spring is tested by using the pre-built quarter bench test platform to obtain the quarter bench test results, and the dynamic characteristics of the air spring are calculated according to the dynamometer test results, the quarter bench test results and the preset formula. The present application gives the test method for the dynamic characteristics of the air spring including the dynamometer test and the quarter bench test, and realizes the test of the air spring with higher efficiency and better expansibility.

[0137] ​​​The air suspension system dynamic characteristic testing device provided by the present application is described below, and the air suspension system dynamic characteristic testing device described below can be correspondingly referred to the air suspension system dynamic characteristic testing method described above.

[0138] Figure 9 is a structural schematic diagram of the retrieval matching device based on a time series database provided by an embodiment of the present application, as Figure 9 indicated, the present application provides a retrieval matching device based on a time series database, comprising: an adjusting unit 910; a testing unit 920; a calculation unit 930;

[0139] Among them:

[0140] The adjusting unit 910 is used for adjusting the air suspension system to a balanced position, wherein the air suspension system comprises an air spring;

[0141] The testing unit 920 is used for performing a dynamometer test on the air spring by using a pre-built dynamometer test platform according to preset excitation parameters, so as to obtain a dynamometer test result;

[0142] The air spring is tested by using a pre-built quarter bench test platform to obtain a quarter bench test result;

[0143] The calculation unit 930 is used for calculating the dynamic characteristics of the air spring according to the dynamometer test result, the quarter bench test result and a preset formula.

[0144] Based on the above embodiment, in the device, the preset excitation parameters include amplitudes and frequencies, each amplitude is tested at all frequencies, each group of tests is continuously performed for a preset number of cyclic excitations, and at least a preset time is interval between adjacent groups of tests.

[0145] Based on the above embodiment, in the device, the air spring is tested by using a pre-built quarter bench test platform to obtain a quarter bench test result, and specifically comprising:

[0146] The on-spring acceleration of the air spring is obtained by using an on-spring acceleration sensor, and the on-spring acceleration sensor is installed above the air spring;

[0147] The under-spring acceleration of the air spring is obtained by using an under-spring acceleration sensor, and the under-spring acceleration sensor is installed below the air spring;

[0148] The excitation acceleration of the air spring is obtained by using an excitation acceleration sensor, and the excitation acceleration sensor is installed at the bottom of the slide rail;

[0149] The stroke sensor is installed on the side of the air spring.

[0150] Based on the above embodiment, in the device, the dynamic characteristics of the air spring are calculated according to the dynamometer test result, the quarter-rack test result and a preset formula, and specifically include:

[0151] According to a first preset formula, the frequency correlation of the air spring is calculated.

[0152] The first preset formula includes:

[0153]

[0154]

[0155]

[0156] K (ω) is the total stiffness; k A is the effective area stiffness; k1 is the high-pressure gas stiffness; c1 is the gas heat exchange equivalent damping; j is the imaginary unit; ω is the excitation frequency; γ is the specific heat capacity ratio; p b0 is the initial pressure; A eff is the effective area; V b0 is the effective volume; C V is the specific heat capacity at constant volume; m b0 is the initial gas mass; K b is the heat exchange coefficient; p b is the gas pressure during motion; p atm is the atmospheric pressure; and z is the vertical displacement.

[0157] Based on the above embodiment, in the device, the dynamic characteristics of the air spring are calculated according to the dynamometer test result, the quarter-rack test result and a preset formula, and specifically include:

[0158] According to a second preset formula, the amplitude correlation of the air spring is calculated.

[0159] The second preset formula includes:

[0160]

[0161]

[0162]

[0163] K (ω) is the total stiffness; k Re is the dynamic stiffness real part; k ImK' is the real part of the dynamic stiffness of the rubber air spring; K" is the imaginary part of the dynamic stiffness of the rubber air spring; A is the excitation amplitude; k A k1 is the high pressure gas stiffness; c1 is the gas heat exchange equivalent damping; ω is the excitation frequency; γ is the specific heat capacity ratio; p b0 p0 is the initial pressure; A eff A is the effective area; V b0 V is the effective volume; C V Cv is the constant volume specific heat capacity; m b0 m0 is the initial gas mass; K b K is the heat exchange coefficient; p b p is the gas pressure during motion; p atm p0 is the external atmospheric pressure; z is the vertical displacement.

[0164] Based on the above embodiment, in the device, the dynamic characteristics of the air spring are calculated according to the dynamometer test result, the quarter-rack test result and a preset formula, and specifically include:

[0165] According to a third preset formula, the transfer characteristics of the air spring are calculated;

[0166] The third preset formula includes:

[0167]

[0168] wherein, is the transfer function from z to z; is the cross-correlation function of z and z; is the autocorrelation function of z; is the Fourier transform of the on-spring acceleration; is the Fourier transform (transpose) of the excitation input; is the Fourier transform of the excitation input.

[0169] ​​In the above specific embodiments, the present invention provides a dynamic characteristic testing device for an air suspension system. The device involves adjusting the air suspension system, which includes an air spring, to a balanced position. Based on preset excitation parameters, a pre-built indicator test platform is used to perform an indicator test on the air spring to obtain the indicator test result. A pre-built quarter-bench test platform is then used to perform a quarter-bench test on the air spring to obtain the quarter-bench test result. Based on the indicator test result, the quarter-bench test result, and a preset formula, the dynamic characteristics of the air spring are calculated. This invention provides a testing method for the dynamic characteristics of air springs, including indicator testing and quarter-bench testing, achieving more efficient and scalable testing of air springs.

[0170] Figure 10 An example is a schematic diagram of the physical structure of an electronic device, such as... Figure 10 As shown, the electronic device may include a processor 1010, a communication interface 1020, a memory 1030, and a communication bus 1040, wherein the processor 1010, the communication interface 1020, and the memory 1030 communicate with each other through the communication bus 1040. The processor 1010 can call logical instructions in the memory 1030 to execute a dynamic characteristic test method for an air suspension system. The method includes: adjusting the air suspension system to a balanced position, wherein the air suspension system includes an air spring; performing a power indication test on the air spring using a pre-built power indication test platform according to preset excitation parameters to obtain a power indication test result; performing a quarter-bench test on the air spring using a pre-built quarter-bench test platform to obtain a quarter-bench test result; and calculating the dynamic characteristics of the air spring based on the power indication test result, the quarter-bench test result, and a preset formula.

[0171] Further, the logic instructions in the memory 1030 described above can be implemented in the form of software functional units and sold or used as independent products, and can be stored in a computer readable storage medium. Based on such understanding, the technical solutions of the present application essentially or the parts that make contributions to the prior art or parts of the technical solutions can be embodied in the form of a software product. The computer software product is stored in a storage medium, and includes a number of instructions for causing a computer device (which can be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of the present application. The aforementioned storage medium includes: a U disk, a mobile hard disk, a read-only memory (ROM, Read-Only Memory), a random access memory (RAM, Random Access Memory), a magnetic disk or an optical disk, and various media that can store program codes.

[0172] In another aspect, the present application also provides a computer program product, which comprises a computer program, the computer program can be stored on a non-transitory computer readable storage medium, and the computer program can be executed by a processor to enable a computer to perform the air suspension system dynamic characteristic test method provided by the above-mentioned methods. The method comprises: adjusting an air suspension system to a balanced position, the air suspension system comprising an air spring; performing a dynamometer test on the air spring according to a preset excitation parameter by using a pre-built dynamometer test platform to obtain a dynamometer test result; performing a quarter bench test on the air spring by using a pre-built quarter bench test platform to obtain a quarter bench test result; and calculating the dynamic characteristic of the air spring according to the dynamometer test result, the quarter bench test result and a preset formula.

[0173] In yet another aspect, the present application also provides a non-transitory computer readable storage medium, which stores a computer program, the computer program is executed by a processor to implement the air suspension system dynamic characteristic test method provided by the above-mentioned methods. The method comprises: adjusting an air suspension system to a balanced position, the air suspension system comprising an air spring; performing a dynamometer test on the air spring according to a preset excitation parameter by using a pre-built dynamometer test platform to obtain a dynamometer test result; performing a quarter bench test on the air spring by using a pre-built quarter bench test platform to obtain a quarter bench test result; and calculating the dynamic characteristic of the air spring according to the dynamometer test result, the quarter bench test result and a preset formula.

[0174] The device embodiments described above are merely illustrative, wherein the units described as separate components can or can not be physically separate, and the components displayed as units can or can not be physical units, i.e., can be located in one place, or can be distributed to multiple network units. Part or all of the modules can be selected to achieve the purposes of the embodiments according to actual needs. Those skilled in the art can understand and implement without creative labor.

[0175] Through the description of the above embodiments, those skilled in the art can clearly understand that the embodiments can be realized by means of software and the necessary general hardware platform, and of course can also be realized by hardware. Based on such understanding, the above technical solutions can be embodied in the form of a software product, which can be stored in a computer readable storage medium, such as a ROM / RAM, a magnetic disk, an optical disk, etc., and includes a number of instructions to make a computer device (which can be a personal computer, a server, or a network device, etc.) execute the methods described in each embodiment or some parts of the embodiments.

[0176] Finally, it should be noted that: the above embodiments are only used to illustrate the technical solutions of the present application, and not to limit them; although the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that: it can still modify the technical solutions recorded in the foregoing embodiments, or make equivalent replacement for part of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. A method of testing the dynamic characteristics of an air suspension system, characterized by, The air suspension system is adjusted to a balanced position, and the air suspension system comprises an air spring. According to preset excitation parameters, the air spring is subjected to dynamometer test by using a pre-built dynamometer test platform to obtain a dynamometer test result, the dynamometer test comprises a sinusoidal excitation dynamometer test; the air spring is subjected to a quarter bench test by using a pre-built quarter bench test platform to obtain a quarter bench test result, the quarter bench test comprises a harmonic excitation test; the preset excitation parameters comprise amplitudes and frequencies, each amplitude is subjected to a test of all frequencies, each group of tests is continuously subjected to a preset number of cyclic excitations, and at least a preset time is interval between adjacent groups of tests. According to the dynamometer test result, the quarter bench test result and a preset formula, the dynamic characteristics of the air spring are calculated, and the dynamic characteristics of the air spring comprise frequency correlation of the air spring, amplitude correlation of the air spring and transmission characteristics of the air spring. The quarter bench test of the air spring by using the pre-built quarter bench test platform to obtain the quarter bench test result specifically comprises: An on-spring acceleration sensor is used to obtain on-spring acceleration of the air spring, and the on-spring acceleration sensor is installed above the air spring; An off-spring acceleration sensor is used to obtain off-spring acceleration of the air spring, and the off-spring acceleration sensor is installed below the air spring; An excitation acceleration sensor is used to obtain excitation acceleration of the air spring, and the excitation acceleration sensor is installed at the bottom of the slide rail; A stroke sensor is used to obtain stroke of the air spring, and the stroke sensor is installed at the side of the air spring. According to the dynamometer test result, the quarter bench test result and a preset formula, the dynamic characteristics of the air spring are calculated, and the dynamic characteristics of the air spring comprise frequency correlation of the air spring, amplitude correlation of the air spring and transmission characteristics of the air spring.

2. The air suspension system dynamic characteristic test method according to claim 1, characterized by, According to a first preset formula, the frequency correlation of the air spring is calculated. The first preset formula comprises: According to the dynamometer test result, the quarter bench test result and a preset formula, the dynamic characteristics of the air spring are calculated, and the dynamic characteristics of the air spring comprise frequency correlation of the air spring, amplitude correlation of the air spring and transmission characteristics of the air spring. where K(ω) is the total stiffness; k A is the effective area stiffness; k1 is the high pressure gas stiffness; c1 is the gas heat exchange equivalent damping; j is the imaginary unit; ω is the excitation frequency; γ is the specific heat capacity ratio; p b0 is the initial pressure; A eff is the effective area; V b0 is the effective volume; C V is the specific heat capacity at constant volume; m b0 is the initial gas mass; K b is the heat exchange coefficient; p b is the gas pressure during motion; p atm is the external atmospheric pressure; z is the vertical displacement.

3. The method of claim 1, wherein According to a second preset formula, the amplitude correlation of the air spring is calculated. The second preset formula comprises: According to the dynamometer test result, the quarter bench test result and a preset formula, the dynamic characteristics of the air spring are calculated, and the dynamic characteristics of the air spring comprise frequency correlation of the air spring, amplitude correlation of the air spring and transmission characteristics of the air spring. where K(ω) is the total stiffness; k Re is the real part of the dynamic stiffness; k Im is the imaginary part of the dynamic stiffness; K ′ is the real part of the dynamic stiffness of the rubber airbag; K" is the imaginary part of the dynamic stiffness of the rubber airbag; A is the excitation amplitude; k A is the effective area stiffness; k1 is the high-pressure gas stiffness; c1 is the equivalent damping of gas heat exchange; ω is the excitation frequency; γ is the specific heat capacity ratio; p b0 is the initial pressure; A eff is the effective area; V b0 is the effective volume; C V is the specific heat capacity at constant volume; m b0 is the initial gas mass; K b is the heat exchange coefficient; p b is the gas pressure during motion; p atm is the external atmospheric pressure; z is the vertical displacement.

4. The method of claim 1, wherein According to a third preset formula, the transmission characteristics of the air spring are calculated. The third preset formula comprises: The air suspension system is adjusted to a balanced position, and the air suspension system comprises an air spring. wherein is to the transfer function; is and the cross-correlation function; is the autocorrelation function; is the Fourier transform of the on-spring acceleration; is the Fourier transform transpose of the excitation input; is the Fourier transform of the excitation input.

5. An air suspension system dynamic characteristic testing device, characterized by, The test unit is configured to perform dynamometer test on the air spring by using a pre-built dynamometer test platform according to preset excitation parameters to obtain a dynamometer test result, and the dynamometer test comprises sinusoidal excitation dynamometer test. ​ ​ The air spring is tested on the pre-built quarter stand test platform to obtain quarter stand test results, and the quarter stand test includes harmonic excitation experiments; the preset excitation parameters include amplitudes and frequencies, each amplitude is tested at all frequencies, each group of tests is continuously performed for a preset number of cycle excitations, and at least a preset time is interval between adjacent groups of tests; when the test unit tests the air spring on the pre-built quarter stand test platform, the on-spring acceleration of the air spring is obtained by using an on-spring acceleration sensor, the on-spring acceleration sensor is installed above the air spring; the off-spring acceleration of the air spring is obtained by using an off-spring acceleration sensor, the off-spring acceleration sensor is installed below the air spring; the excitation acceleration of the air spring is obtained by using an excitation acceleration sensor, the excitation acceleration sensor is installed at the bottom of the slide rail; and the stroke of the air spring is obtained by using a stroke sensor, the stroke sensor is installed on the side of the air spring. The calculation unit is configured to calculate the dynamic characteristics of the air spring according to the dynamometer test results, the quarter stand test results, and a preset formula, wherein the dynamic characteristics of the air spring include frequency dependence of the air spring, amplitude dependence of the air spring, and transfer characteristics of the air spring.

6. An electronic device comprising a memory, a processor, and a computer program stored on the memory and executable on the processor, characterized in that, The processor executes the program to implement the air suspension system dynamic characteristic test method according to any one of claims 1 to 4.

7. A non-transitory computer-readable storage medium having stored thereon a computer program, characterized in that, The computer program is executed by the processor to implement the air suspension system dynamic characteristic test method according to any one of claims 1 to 4.

8. A computer program product comprising a computer program, characterized in that, The computer program is executed by the processor to implement the air suspension system dynamic characteristic test method according to any one of claims 1 to 4.

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