Abstract: Based on the real analogy between the inerter-spring-damper mechanical system and the capacitor-inductor-resistor electrical system, an inerter-spring-damper (ISD) vehicle suspension system with two stages connected in series is proposed according to the principle of cascaded filter. In such a suspension system, the first stage is a conventional passive suspension, and the second stage is a parallel inerter-spring-damper. A half-car vehicle model is built to analyze performance of the suspension system under random and pulse input, and to investigate effects of the second suspension stiffness on system performance. The results indicate that in contrast to conventional suspension, the proposed suspension has a better dynamic performance, and improvements of 81%, 81%, 79% and 82.8% are obtained for PSD peak values of vertical acceleration of the centre of body mass, pitch acceleration of body, dynamic tire load of front and rear wheels in lower-frequency stage. The results further show that the proposed suspension can effectively suppress body resonance, better ride comfort, and improve trade-offs of the ride and handling.

Key words: Automotive engineering, Inerter, Ride comfort, Ride safety, Two-stage vibration isolation, Vehicle suspension