Sliding Mode Control of a Quarter Car Active Suspension System Using a New Method For Extracting Optimal Slidng Surface

In this paper, a new method for extracting sliding surface has been presented about a linear system with parametric uncertainties with known bound. In the proposed method, common signal of first order sliding mode control has been applied to the system and then the sliding surface is extracted as a virtual controller with the aim of minimizing a cost function. The main advantage of the proposed method is the possibility of setting the distance of the state trajectory from the sliding surface setting one of the design parameters. Thus, It is possible to near the ultimate goal of sliding mode control, i.e. staying the state trajectory on the sliding surface, without increasing the degree of sliding mode control, while the amount of used energy will be controlled, too. In order to show the efficiency of the method, a quarter car active suspension system has been chosen and the proposed method in the selection of position subsystem sliding surface is used.