Dynamic characteristics analysis of spatial suspension mechanisms based on instantaneous screws

Multi-link, MacPherson and double-wishbone independent suspensions affect the dynamic characteristics of a passenger car strongly. This paper presents a unified quarter-vehicle model which incorporates both the spatial suspension kinematics and the tyre dynamics for the dynamic analysis of these three spatial suspensions. The quarter-vehicle model consists of a spatial suspension mechanism and a ground-wheel contact model. The dynamic characteristics analysis of a vehicle running on the uneven road is mainly divided into three steps. Firstly, the corresponding instantaneous screws are determined for the quarter-vehicle model. Then, the theory of screws is used to describe the kinestatics of the quarter-vehicle model. Finally, on basis of the kinestatic relations, Lagrangian function is applied to the dynamic analysis. As to the feasibility of the theoretical method, the different road disturbances are considered in the numerical examples. The simulation results are compared with Adams/View software to verify the numerical performances of the dynamic analysis.