Reduction of the reaching mode by the sliding mode control with time-varying sliding surface

In this paper, a sliding mode control method with time-varying sliding surface is proposed. The greatest characteristic of sliding mode control is its robustness against uncertainties, such as disturbances, modeling error, or parameter variation. Robustness is guaranteed only if uncertainties satisfy the matching condition, so it is important to shorten reaching time. We can get shorter reaching time, and time to converge to the equilibrium point than the conventional linear sliding surface by using time-varying sliding surface. We verify that time-varying sliding surface can get smoother error convergence and less energy consumption than time-invariable sliding surface through simulation of the vehicle positioning control considering ride comfort with time-varying sliding surface.