Correlative Analysis of Hydraulic Bushing of Suspension Control Arm and Full Vehicle Ride Comfort

Abstract

To analyze and compare the vehicle performance effects of hydraulic bushings with those of the traditional rubber bushings of double wishbone front suspensions, we test the static and dynamic properties of the hydraulic bushings of control arms. The mechanical model is built in ADAMS and is then used as the basis for establishing the full vehicle model. The random road surface spectra of different levels are built using the harmony superposition method. The ride comfort of the full vehicle with a control arm installed with hydraulic and rubber bushings is simulated on random and bump roads. The frequency spectrum characteristic and root mean square (RMS) of the vertical and longitudinal acceleration of the foot floor and seat rail are calculated via power spectrum estimation, and the handling stability of the full vehicle is then simulated. The effects of the change in hydraulic bushing stiffness on ride comfort are finally analyzed. The following results are obtained. (1) The effects of such change on vehicle handling are relatively small regardless of the type of bushing used. (2) The vehicle shows acceptable ride comfort on level A and level B roads but shows poor ride comfort on bump road when a hydraulic bushing is used. (3) Large hydraulic bushing stiffness increases the vertical acceleration RMS on level A, level B, and bump roads. However, the variety of RMS is extremely small on level D roads, the responses of the vertical and longitudinal acceleration curves are slow, and the time oscillation of the curves is relatively long on bump road.