Concept design and dynamics analysis of a novel lightweight vehicle suspension combined with driving units

Abstract

A lightweighted suspension concept with integrated driving units into the longitudinal arm is proposed, to meet the increasing requirements from environments on both lightweight and propulsion to electric vehicles. This paper focuses on the structure concept design and ride dynamic analysis of the suspension with combined driving units. Besides conventional springs and shock absorbers, this concept suspension consists of a mass reduced axle structure, longitudinal arms, and electric driving units. The electric driving unit of the concept suspension arm is introduced by structural illustration first which in structure integrates the function as the suspension longitudinal arm and the function of electric propulsion to the vehicle. Meanwhile, a light brace structure with tube profiles is developed on the basis of topological optimization. Through the structure optimization, it can fulfill the suspension kinematic and compliance as well as mechanical requirements. The vehicle suspension realizes mass reduction not only from integration of driving units and suspension arm but also from structure optimization. In order to investigate the ride dynamics of the conceptual suspension, an analytical model for vehicle rear axle with a double lane road signal in accordance with International Organization for Standardization road surface profile is derived, with consideration of the integrated electric motor and linkage geometry. Simulation results are obtained to illustrate the ride dynamics in contrast to a conventional suspension benchmark. The simulation results indicate that the concept suspension has comparable ride dynamics performance as the reference suspension. Finally, the influences of the important parameters on ride dynamics are analyzed.