Design Optimization of Suspension and Steering Systems for Commercial Vehicles

Abstract

Steering system is used to provide directional stability for the vehicle, and suspension system is to provide ride comfort and transfer acceleration, braking and cornering loads from road wheels to frame and body. Thus, both steering and suspension systems play a very important role in vehicle ride and handling characteristics. Vehicle drift or the steering pull is the deviation of vehicle path from a straight line while braking and is related to various parameters of suspension, steering, tires, and wheel alignment. Analyses of steering and suspension characteristics such as brake steer and bump steer which affect vehicle drift play an important role. This research deals with multi-body simulation-based optimization of the parameters of suspension and steering systems by focusing on their dynamic interaction between the two systems and thereby helps to achieve the targets (bump steer-4°/m and brake steer-0.01°/kN). Commercial vehicle industry is currently aiming toward the development of vehicles with improved passenger safety and comfort at lower cost. In general, the steering systems of longer front overhang (FOH) vehicles have multiple steering linkages instead of conventional draglink arrangement because of design and packaging constraints. The paper handles the design of high-strength draglink for longer FOH vehicle by eliminating multiple linkages and reducing the cost by Rs. 2000.