Analytical model for combined ride and handling with leaf spring suspension in commercial vehicles

Ride comfort and handling are very important characteristics that influence a customer's decision to purchase a vehicle. Hence designing the suspension characteristics to improve the ride and handling performances is very crucial. During the product development cycle, the suspension system parameters are optimised through a number of iterations using design simulation tools such as ADAMS, TruckSim, etc. before the actual prototype is developed. The simulation time for iterations in these design-simulation tools is very high. In the present paper, an attempt has been made to reduce the iteration time by developing an analytical model in MATLAB for combined vertical and lateral dynamics simulation with 11 degrees of freedom. The suspension system, i.e., rigid leaf spring, is transformed into a three-link mechanism by the two-point deflection method as described in the SAE AE-II spring design manual. The simulation results correlated well with the ADAMS/Car simulation results.