Simulating effects of suspension damper degradation on common sensor signals for Diagnosis Models in the Context of Condition-Based Maintenance

Abstract

Degraded suspension dampers strongly influence vehicle safety and ride comfort, but often occur after several years of operation. Related workshop checks are usually not degradation-adaptive, so they can be significantly delayed to the need for maintenance. To make the maintenance adaptive to degradations, onboard diagnosis methods can be used, which rely on the degradation status extracted from sensor signals.To support the development of sensitive yet robust diagnosis models, a model that can simulate and explain the effects of damper degradation in common sensor signals is proposed. This paper focuses on low-frequency effects in signals of the wheel speed sensors, which are ultra low cost and always available in modern vehicles. As a result, the model shows a good qualitative match to real-world test drives, specifically in the frequency domain. Therefore, various real-world measurements were conducted, in particular, test bench measurements of degraded dampers and vehicle on-road tests.