Assessment of the influence of nonlinear characteristics of suspension components, shock absorber, on the results of their diagnostic

Abstract

Shock absorbers in a car are a key element of the suspension, which provides comfort and safety when driving. They work in tandem with an elastic device, absorbing the energy of impacts and shocks that occur when driving over uneven roads. The shock absorber prevents body swaying, reduces vibration and provides a smoother movement of the body. In the process of operation, the parameters of the shock absorber decrease, safety and comfort, vehicle performance decrease, vehicle stability deteriorates, braking distance increases, body swaying progresses when driving, knocks and noises appear in the suspension, uneven tire wear. This necessitates periodic monitoring of the shock absorber condition using diagnostics. There is a widespread lack of disassembly diagnostics, fragments of installation and dismantling robots are very labor-intensive, requiring the need for special equipment and qualified specialists. In practice, bench diagnostics are used by activating the suspension with a periodic signal, in which, to a large extent, it is not the shock absorber that is tested, but the suspension. Therefore, when testing the assembled suspension, the shock absorber testing section contains information about other suspension components. This is a source of errors in shock absorber diagnostics. Suspension components can have both linear and nonlinear characteristics, and both of them, through the presence of errors and untimely replacement of the shock absorber, can limit its actual performance. In this paper, using the simulation modeling method, the influence of nonlinear characteristics, such as dry friction and play in the suspension, on the error in shock absorber diagnostics is considered.

Keywords: shock absorber, diagnostics, nonlinear characteristics, errors, modeling