CN-122016354-A - Method and system for testing dynamic damping coefficient of vehicle suspension

CN122016354ACN 122016354 ACN122016354 ACN 122016354ACN-122016354-A

Abstract

The invention provides a method and a system for testing dynamic damping coefficients of a vehicle suspension, which relate to the field of suspension testing and aim at solving the problems that the time and the labor are consumed, the testing efficiency is low when the dynamic damping of the suspension is tested by the existing rack, and the deviation of damping parameter testing results is large because the actual working condition of the suspension is difficult to truly reproduce; the method has the advantages that a bench test is not needed, a spring damping element is not needed to be disassembled, the method is efficient, quick, simple and convenient, the measuring process is based on the running working condition of the whole vehicle, the displacement deformation of the suspension spring and the load are fed back by the actual working condition, and the obtained result is more accurate.

Inventors

GAO YANG
HE LEI
CHENG HAO
GUO NIANCHENG
WANG YUANBO
YANG HAI
SUN HAONAN

Assignees

山东大学

Dates

Publication Date: 20260512
Application Date: 20260410

Claims (10)

1. A method for testing a dynamic damping coefficient of a vehicle suspension, comprising: acquiring acceleration signals of the non-sprung mass part and the sprung mass part, identifying the sprung mass resonance frequency after processing, acquiring the amplitude frequency value of the non-sprung mass part and the amplitude frequency value of the sprung mass part, and calculating the amplitude ratio of the non-sprung mass part and the sprung mass part; And establishing a two-degree-of-freedom dynamic model of the suspension, obtaining a dynamic differential equation, constructing a vibration amplitude related quantity and an equivalent relation which are transmitted to a sprung mass part after the damping action of the suspension based on the differential equation, calculating and solving by combining the amplitude ratio, the sprung mass resonance frequency, the dynamic stiffness of the suspension spring and the sprung mass based on the equivalent relation, and calculating to obtain the dynamic damping coefficient of the suspension of the vehicle when the sprung mass resonates.
2. The method for testing the dynamic damping coefficient of a vehicle suspension according to claim 1, wherein the acceleration signals of the unsprung mass portion and the sprung mass portion are obtained when the vehicle is in a flat road running condition.
3. The method of claim 2, wherein the acceleration signals of the unsprung mass portion and the sprung mass portion are obtained when the vehicle is in an acceleration or coasting condition.
4. The vehicle suspension dynamic damping coefficient testing method according to claim 1, wherein said post-processing identification of sprung mass resonance frequency comprises: And performing frequency spectrum transformation on the acceleration signal, and identifying the sprung mass resonance phenomenon and the sprung mass resonance frequency based on the frequency spectrum.
5. The method for testing the dynamic damping coefficient of a vehicle suspension according to claim 4, wherein after identifying the sprung mass resonance frequency, the rotational speed characteristic parameter at the time of sprung mass resonance is recorded; And carrying out multi-round uniform speed test based on the rotating speed characteristic parameters, recording the amplitude ratio of the non-sprung mass part and the sprung mass part tested in each round, and substituting the average value into a calculation formula of the dynamic damping coefficient.
6. The method of testing a dynamic damping coefficient of a vehicle suspension according to claim 5, wherein said rotational speed characteristic parameter is one of a vehicle speed, a certain gear engine rotational speed, and a certain gear propeller shaft rotational speed.
7. The method of testing a dynamic damping coefficient of a vehicle suspension according to claim 1, wherein the acceleration signal is acceleration data of the unsprung mass portion and the sprung mass portion in a direction perpendicular to the ground.
8. The method for testing the dynamic damping coefficient of a vehicle suspension according to claim 1, wherein the dynamic stiffness of the suspension spring is obtained through a preliminary test.
9. A vehicle suspension dynamic damping coefficient test system, comprising: The parameter acquisition module is configured to acquire acceleration signals of the non-sprung mass part and the sprung mass part, identify the sprung mass resonance frequency after processing, acquire the amplitude frequency value of the non-sprung mass part and the amplitude frequency value of the sprung mass part, and calculate the amplitude ratio of the non-sprung mass part and the sprung mass part; The dynamic damping coefficient calculation module is configured to establish a two-degree-of-freedom dynamic model of the suspension and obtain a dynamic differential equation, construct a vibration amplitude related quantity and an equivalent relation which are transmitted to a sprung mass part after the damping action of the suspension of the vehicle based on the differential equation, calculate and solve by combining the amplitude ratio, the sprung mass resonance frequency, the dynamic stiffness of the suspension spring and the sprung mass based on the equivalent relation, and calculate the dynamic damping coefficient of the suspension of the vehicle when the sprung mass resonates.
10. The vehicle suspension dynamic damping coefficient testing system according to claim 9, wherein after identifying the sprung mass resonance frequency, the rotational speed characteristic parameter at which the sprung mass resonates is recorded; And carrying out multiple rounds of uniform speed tests based on the rotating speed characteristic parameters, recording the amplitude ratio of the unsprung mass part and the sprung mass part in each round of test, and substituting the average value into a calculation formula of the dynamic damping coefficient.

Description

Method and system for testing dynamic damping coefficient of vehicle suspension Technical Field The invention relates to the field of suspension testing, in particular to a method and a system for testing a dynamic damping coefficient of a vehicle suspension. Background The automobile suspension consists of an elastic element, a shock absorber, a guide mechanism and the like, and has key effects on smoothness and passenger comfort in the running process of the automobile. Typical spring elements are leaf springs, coil springs, air springs, hydro-pneumatic springs, etc. During running of the vehicle, the damper and other elements provide damping force, so that energy transferred to the sprung mass by the road surface is dissipated, and vibration is reduced. In addition, due to friction, the suspension element may experience hysteresis in the direction perpendicular to the ground, and may also experience a certain vertical damping force. In the process of matching the suspension, the sum of the damping of the shock absorber and the friction damping of the suspension is an important parameter affecting the smoothness of the vehicle, especially when the sprung mass resonates, if the damping is unreasonably matched, the problems of amplified amplitude, deterioration of comfort and the like can be caused, so that the dynamic damping coefficient of the suspension must be effectively measured and calibrated. At present, the damping of the suspension is measured by a bench test, the work of the damping force in a cycle process is obtained through a bench loading-unloading curve, and the equivalent damping coefficient of the suspension is calculated based on the work. However, the suspension spring has nonlinear characteristics, is influenced by factors such as friction and the like, and the damping characteristics of the same elastic element during the resonance of the sprung mass under the excitation of different axle loads and different roads are possibly different, so that the bench test is difficult to reproduce various actual working conditions. During actual testing, not only parts are required to be disassembled, but also an additional displacement sensor is required to measure the amplitude of the suspension, the testing process is complex, time and labor are wasted, the efficiency is low, the deviation of the obtained damping parameter result is large, the precision is low, and the measurement requirement of the dynamic damping of the suspension is difficult to meet. Disclosure of Invention In order to solve the technical defects, the invention provides a method for testing the dynamic damping coefficient of a vehicle suspension, which is used for measuring the amplitude ratio of sprung and unsprung measuring points when the sprung mass resonates under the running working condition of the vehicle, deriving the damping coefficient of the suspension based on the amplitude ratio, the sprung mass resonance frequency, the dynamic stiffness of the suspension spring and the sprung mass parameter, and accurately and efficiently obtaining the damping coefficient of the suspension. The first object of the invention is to provide a method for testing the dynamic damping coefficient of a vehicle suspension, which adopts the following scheme: acquiring acceleration signals of the non-sprung mass part and the sprung mass part, identifying the sprung mass resonance frequency after processing, acquiring the amplitude frequency value of the non-sprung mass part and the amplitude frequency value of the sprung mass part, and calculating the amplitude ratio of the non-sprung mass part and the sprung mass part; And establishing a two-degree-of-freedom dynamic model of the suspension, obtaining a dynamic differential equation, constructing a vibration amplitude related quantity and an equivalent relation which are transmitted to a sprung mass part after the damping action of the suspension based on the differential equation, calculating and solving by combining the amplitude ratio, the sprung mass resonance frequency, the dynamic stiffness of the suspension spring and the sprung mass based on the equivalent relation, and calculating to obtain the dynamic damping coefficient of the suspension of the vehicle when the sprung mass resonates. Further, under the running condition that the vehicle is in a straight road section, acceleration signals of the unsprung mass part and the sprung mass part are obtained. Further, under the condition that the vehicle is in an acceleration working condition or a sliding working condition, acceleration signals of the unsprung mass part and the sprung mass part are obtained. Further, the identifying the sprung mass resonance frequency after processing includes: And performing frequency spectrum transformation on the acceleration signal, and identifying the sprung mass resonance phenomenon and the sprung mass resonance frequency based on the frequency spectrum. Further, after the sprung mass resonan