Drop test single-degree-of-freedom vehicle model-based vehicle parameter identification method

Abstract

The invention discloses a drop test single-degree-of-freedom vehicle model-based vehicle parameter identification method, which comprises the following steps of: setting measurement points on a vehicle; identifying intrinsic frequencies of the vehicle under a no-load condition and a damping ratio and a vibration mode, which correspond to each intrinsic frequency by using a plurality of drop tests; adding mass onto a vehicle body, performing the drop tests respectively, and identifying intrinsic frequencies of the vehicle under a loading condition and a damping ratio and a vibration mode, which correspond to each intrinsic frequency; calculating the vertical stiffness of the vehicle body, the sprung weight of the vehicle body, pitching stiffness, pitching rotating inertia, side-tipping stiffness and side-tipping rotating inertia; calculating the stiffness Ksf of a front suspension and the stiffness Ksr of a rear suspension; calculating tire stiffness which is consistent with an actual stiffness result; and performing method accuracy verification. In such a way, requirements on test equipment are low, the tests are high in operability, the cost of a single test is lower, the accuracy is high, and a physical parameter calculation method is simpler.

Description

technical field [0001] The invention relates to the field of vehicle parameter identification, in particular to a vehicle parameter identification method based on a drop test single-degree-of-freedom vehicle model. Background technique [0002] Vehicle parameters include modal parameters and physical parameters. Modal parameters mainly refer to: natural frequency, damping ratio, mode shape. The physical parameters have practical physical meanings, among which the more important parameters are the suspension stiffness, damping, sprung mass, unsprung mass, roll moment of inertia, pitch moment of inertia, tire stiffness and related geometric parameters and other parameters. [0003] Why identify modal parameters: [0004] The three modal parameters are very important, because the modal parameters are the basis for identifying the physical parameters. In addition, the modal parameters can also be directly used to evaluate the car’s ride comfort and other performances. If its v...

AI Technical Summary

Problems solved by technology

[0004] The three modal parameters are very important, because the modal parameters are the basis for identifying the physical parameters. In addition, the modal parameters can also be directly used to evaluate the car’s ride comfort and other performances. If its vertical natural frequency and human If their own natural frequency is very close, it will seriously affect the ride comfort

The disadvantage of this method is that the four-channel system test bench is very expensive, only a few large companies, research institutes or schools have this kind of equipment, and the cost of a single experiment is also very expensive

Images