Design of Anti-lock Braking System Compatible with Different Road Conditions for Trucks

Anti-lock braking system (ABS) prevents the wheels from being locked in hard braking conditions and reduces the vehicle stopping distance to the minimum value by regulating the tire longitudinal slip at its optimum value. This paper presents a two-layer controller for ABS of trucks which is adaptable with different road conditions. In the upper layer, a fuzzy controller is designed to calculate the optimum longitudinal slip of each wheel for which the maximum braking force is achieved in different conditions. In the lower layer, a nonlinear controller is analytically designed based on the predictive method to track the optimum wheel slips calculated from the upper layer. In order to increase the robustness of the controller in the presence of system uncertainties, the integral feedback technique is also appended to the predictive method. All simulation studies are conducted using the professional software of Truck Sim to evaluate the performance of the controlled system in a real condition. The results show the effectiveness of the proposed control system in improving the braking performance of trucks in different road conditions.