Designing a Sliding Mode Controller for Antilock Brake System

Antilock brake system (ABS) has been designed to achieve maximum negative acceleration by preventing the wheels from locking. Researches show that the friction between road and tire is a nonlinear function of wheel slip. Therefore, maximum negative acceleration can be achieved by designing a suitable control system for wheel slip regulation at its optimum value. Since there is a lot of nonlinearity and uncertainty (uncertainty in mass and center of gravity of the vehicle and road condition) in vehicle dynamic, a robust control method should be used. In this research, the sliding mode control has been designed based on one of the complete and complex vehicle model. One of the common problems in sliding mode control is chattering phenomena. In this paper, primary controller design has been improved using integral switching surface to reduce chattering phenomena. Simulation results show the success of integral switching surface in elimination of chattering and high performance of this controller. At the end, the performance of designed controller has been compared with one of the related paper results to determine the performance of sliding mode control with integral switching surface