A sliding mode controller for anti-lock brake system: usage of sluggish actuators

Anti-lock brake systems (ABS) become popular nowadays as one of the most important automotive technologies for active safety. The main role of ABS is to prevent wheels from locking by ensuring tire slip ratio within a certain range while braking on slippery road surfaces. It is very important for an ABS controller to increase robustness against uncertainty in vehicle dynamics which is substantially changed by road surface conditions, vehicle mass and other factors. Besides, an inherent nonlinearity in a braking mechanism should be taken into account at the design of a controller. In the case of large commercial vehicles, the brake actuators are more sluggish in response than these of passenger cars, which make it difficult to design an ABS controller having a good performance. To deal with the nonlinearity we use the methodology of sliding mode control. A new method to use sluggish actuators with sliding mode controller is proposed