The simulation and optimization of vehicle ride comfort based on vehicle dynamic model with five degrees of freedom

The paper describes the current research situation of automotive ride comfort from two aspects of experimental and simulation. The dynamics model with five degrees of freedom of a bus is established, meanwhile the kinetic equations is also derived according to D´Alembert principle. A road simulation model of class B is also established on the basis of white noise method. Combined with vehicle model and road model, the model of Matlab/Simulink is built. The vertical acceleration RMS on the seat is objective function and stiffness and damping of front and rear suspension are optimization variables. On the basis of GB/T4970-2009, the acceleration RMS is optimized in the speed interval of 50km / h and 100km / h. After been optimized, the RMS is reduced by about 10% and the effect is obvious at 60km / h.