Determining the Important Degrees of Freedom in Road Reproductions

In this paper, singular value decomposition, principle component analysis and multicoherence analysis is used to evaluate the number of important degrees of freedom in acceleration based road load data, which constitute the targets for road reproduction experiments on a hydraulic shaker table. It is therefore important to determine from this road data how many degrees of freedom need to be included in the road reproduction experiments.

The multi-axial nature of the input and the suspension response is illustrated based on target data from different road surfaces, acquired on the road and on the road dynamometer, as well as on the reproduction results of these tracks using tire patch and spindle based excitation on the K.U.Leuven high frequency multi-axial shaker table.