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This paper describes a methodology that has been developed to apply basic concepts of pattern recognition to isolate “events” in any type of time history data. The results obtained from this methodology can be used for a variety of engineering applications. In this study, it has been applied to estimate and compare the cumulative structural fatigue damage from single bump excitations versus resonance in Class 8 tractors based on consumer highway data. Using the basic concepts of pattern recognition, which include statistical methods based on correlation functions, windowing techniques and root mean square values, a similarity search has been performed to extract and classify known consequential time history traces (events) from the set of acquired data. The advantage of this model is seen in extracting events whose exact time traces are not known.

This paper reviews existing approaches to the estimation of the state of wear of an automotive damper, with the aim of developing a methodology for a quick and effective diagnostic procedure that could be carried out in any repair facility. It has always been desirable to leave the shock absorber in place at the time of such testing, and there are three general procedures that claim to be effective at determining damper wear. This research investigates a method of controlling a short drop of each corner of the vehicle while measuring the acceleration. The acceleration data is then analyzed with the aim of estimating the decay rate of the resulting oscillation, which is known to be related to the damping ratio of the suspension system. The rate of decay is then used to infer the condition of the vehicles damper. The paper reviews the state of the art, describes the methodology and presents experimental validation of a new concept.