Study Of Variable Structure Mode-Following Control For Semi-Active Suspension In Vehicle

Firstly, the quarter-car dynamics model has been designed and fabricated to verify the performance in this paper, which is based on the vehicle dynamics theories. Sliding mode control scheme is put forward to solve the control question of semi-active suspension, integrating with the theory and technique of vibration control. A Sliding Mode Controller and a Variable Structure Mode-Following Controller (VSMFC) for semi-active suspension systems have been designed on the basis of sliding mode control principle, VSMFC utilizes an optimal control schemes for an active suspension as a reference model.Secondly, the simulation models of these controllers have been designed through using the software MATLAB/SIMULINK. Numerical simulations demonstrate the validity and feasibility of the VSMFC. Compared with passive suspension, the acceleration of the sprung mass is kept to a minimum, and the deflections of the suspension and tyre is reduced in a degree, and the control force is very small. In particular, the robustness of the scheme is investigated through computer simulation, when the parameters of suspension are changed. The efficacy of the scheme is shown.Lastly, the VSMFC of semi-active suspension using a quarter-car model on basis of the nonlinearities of suspension such as a hardening spring has been investigated. Simulation results show the advantages of the variable structure mode-following control scheme with realistic nonlinearities.