A technique is discussed whereby vehicle vibration problems can be defined and analyzed using a random vibration input, and analyzing the output statistically. The input consists of a random “white noise” input signal to electromechanical shakers which drive the wheel spindles of an actual automobile. The output analysis is of two types. In the one, vibration instrumentation signals are analyzed with an analog computer to yield a direct measurement of the vehicle transfer function. In the second, subjective impressions are analyzed of vibration sensation experienced by passengers within the vehicle. This approach has the advantage of a controlled laboratory experiment in which suspension and structural changes can be analyzed as to their effect on vehicle vibration. It also allows a comparison of subjective impressions with physical measurements.
