Abstract
This paper presents study on suspension control for heavy-duty trucks considering road holding ability with variable damping shock absorber. In heavy-duty trucks, the large payload, changing in the wide range, causes unstable vehicle behavior such as rollover. So, variable damping property is necessary. In order to reduce the cargo vibration and improve the road holding ability, linear functions of the damping ratio are introduced and examined, which are represented as functions of loading ratio. Next, with results of linear analysis, a nonlinear damping force characteristic is proposed. The nonlinear damping force characteristic has high damping coefficient around zero stroke velocity and low damping force level in the range of high stroke velocity. It is found that the proposed nonlinear damping force characteristic is effective for the compatibility of the vibration isolation and road holding ability.
