Parametric sensitivity analysis of a heavy duty passenger vehicle suspension system

Suspension system design plays an important role in improving passenger comfort and road holding capabilities of an automobile. There is a compromise between the road holding and ride comfort. While Ride comfort is directly related to the acceleration sensed by passengers when traveling on a rough road, road holding ability is associated with the contact forces of the tires and road surface. Suspension travel or working space refers to the relative displacement between the sprung- mass and the un- sprung masses of the vehicle. The present mathematical work aims to determine the discomfort, road holding and working space in a passenger bus by using MATLAB through a quarter car model. The variabilities in the parameters of spring stiffness and damping are used to evaluate the standard derivations of the vertical vehicle body accelerations, tire radial force and relative displacement between wheel and vertical body. The rational selection of damping and suspension stroke and an estimation of speed limits can be had from these studies.