Modelling and Dynamic Response Characteristics Study of a PAM Bionic Kangaroo Leg Suspension

A PAM (pneumatic artificial muscle) bionic kangaroo leg suspension is proposed on the basis of a kangaroo leg structure evolved from long-term hopping; the modelling and characteristics research are conducted to pursue a high-performance vehicle suspension system. Based on the PAM and kangaroo leg bone proportions, the bionic suspension structure is constructed by analysing and refining the kangaroo leg structure and functions. The dynamic equations are derived by the Lagrange's Equations considering the rods system features and an Adams simulation model is built up to study the damping performance and parameter characteristics of the suspension. Moreover, a co-simulation of Adams and Matlab is performed under fuzzy control and PID control. The dynamic response characteristics of the suspension is simulated and analysed under the passive and active modes in the time and frequency domains. The result indicates that the vibration and shock of the vehicle body can be reduced effectively by the proposed suspension in passive, fuzzy control and PID control modes; compared with the passive mode, the damping performance of the suspension is better under the active control. The fuzzy control and the PID control are effective to reduce the suspension transmissibility, especially in the medium frequency ranges, and the two control effects are better than that of the passive mode in most frequency bands. The study result of this paper can provide a reference for the research and development of high-performance bionic suspension.