The Laboratory Simulation of Vehicle Service Stress

A simulation technique which will enable the response of vehicle components or complete vehicles to be reproduced in the laboratory is presented. For the case of a complete four wheeled vehicle it is shown how synthesized random displacements, based on a knowledge of the road surface undulations, can be derived; it is demonstrated that the information necessary to derive these four signals can be obtained from the spectral density evaluated from a single traverse along the road. Comparison is made between vehicle response measured on the test track, and the response on the simulator under synthesized random displacements and point-by-point profile excitation.