Servomechanism analysis of a two-rate spring automobile suspension.

Abstract

Some of the methods of automatic control are used to investigate the feasibility of a suspension system using a spring with two spring rates. Following a disturbance the spring rate is changed discontinuously from one value to the other in such a manner that a damping action results. A single degree of freedom corresponding to the vertical motion of the automobile body with respect to one wheel is considered and this system is simulated on the analog computer. The objectives of this investigation are: (1) to determine the effect of the spring in reducing the frequency response resonance peak. (2) to determine the transient response characteristics of the system when subjected to a step disturbance. The results show that the two-rate spring does provide a significant amount of damping.