Suspension characteristic test vehicle wheel six-degree-of-freedom displacement measurement device and method

Abstract

The invention discloses a suspension characteristic test vehicle wheel six-degree-of-freedom displacement measurement device and method. The device mainly comprises a first binocular vision measuring instrument (41), a second binocular vision measuring instrument (42), optical targets, a data exchange device (5), an upper computer (6), a vehicle wheel positioning fixture (3) and a reference fixture (2); a measured vehicle (8) is fixed on a test bench (7); the vehicle wheel positioning fixture and the reference fixture are respectively installed on a vehicle wheel and a frame; the optical targets are distributed on the measuring planes of the fixtures and a vehicle body; and the upper computer is connected with the binocular vision measuring instruments through the data exchange device, controls the binocular vision measuring instruments to measure the spatial coordinate change of the optical targets, calculates the six-degree-of-freedom displacement of the vehicle wheel under a vehicle coordinate system. According to the suspension characteristic test vehicle wheel six-degree-of-freedom displacement measurement device and method of the invention, the six-degree-of-freedom displacement of the vehicle wheel under the vehicle coordinate system is solved according to the spatial coordinate change of the optical targets, and accurate non-contact measurement can be realized. The measurement device and method of the invention have the advantages of convenient and flexible measurement, wide test range, high precision and bright application prospect.

Description

technical field [0001] The invention belongs to the technical field of automobile suspension performance testing, and in particular relates to a six-degree-of-freedom displacement measuring device and method for a suspension characteristic test wheel. Background technique [0002] Because most of the suspension components are connected to the body through rubber bushings and move relative to the body, the characteristics of the suspension are usually described in the vehicle coordinate system to study the influence of body motion and tire force on the wheel alignment parameters. The traditional automobile suspension characteristics test bench adopts the quasi-static loading method to simulate the force and displacement movement of the vehicle when driving on the road on the test bench. Usually, the vehicle body is fixed on the test bench to load the wheels. The six-degree-of-freedom displacement measuring device and method measure the changes of some wheel positioning parame...

AI Technical Summary

Problems solved by technology

[0005] This method needs to identify the relative position of the end axis of the measuring arm and the rotation axis of the wheel, and correct the model parameters of the measuring arm to ensure the accuracy of the six-degree-of-freedom displacement calculation of the wheel. Moreover, the measuring arm mechanism is connected in series, and there is a cumulative error; the coordinates of the measuring arm are required during the test. Each coordinate axis of the vehicle coordinate system is parallel to each coordinate axis of the automobile coordinate system, which requires high installation accuracy of the measuring arm; one end of the measuring device is fixed with the fixture, and the impact, flexibility and gravity of the mechanism will affect the dynamic feedback of the joint corner; the other part of the measuring device One end is fixed with the test bench, and it is inconvenient to move

[0006] The other uses a wire-type displacement sensor to measure the displacement changes of the six degrees of freedom of the wheel. It mainly includes 5 pull ropes and a measuring disk that fixes the pull rope. The wheel can rotate around the Y axis relative to the measuring disk. The photoelectric encoder installed on the measuring disk measures the wheel The rotation angle is used to obtain the wheel rotation angle, the longitudinal and vertical displacements of the wheel center are measured by the cables along the X and Z axes respectively, and the lateral displacement, toe angle and camber angle of the wheel center are measured by three cables along the Y axis. The displacement sensor has better solved the problem of insufficient resolution of the early angle sensor, but the measurement accuracy will decrease when the body moves faster

Images