Vehicle modeling for integrated control design

Abstract

This paper comprises the control-oriented modeling of an integrated vehicle system including powertrain, brake, active suspension and steering components. As the first step, the models of a vehicle are formalized. In the powertrain model the nonlinearities of an engine with thermodynamical and fluid mechanical features are considered. In the model of suspension the dynamics of sprung mass (body) and unsprung masses (e.g., wheels) are considered. In the brake system the necessary hydraulic pressure required for the desired brake power is determined. The pressure fluctuation arising from the skewness of brake disc during the rotation is distributed. The mechanical construction of electronic steering system is also dealt with. The model of the vehicle handles the effects of road and wind disturbances. Matlab/Simulink, CarSim and GT-Suite GT-Power are used during the simulations. Matlab/Simulink is a perfect tool for control design and a fast analysis of the operation of the controlled system. CarSim is a widely used vehicle dynamic simulator used wide-spread; GT-Power is a complex powertrain modeling program. Both are used for validating Matlab models.