Integrated Control of Active Suspension and Anti-lock Braking System Based on the Nonlinear Improved Sliding Mode Control System

In this paper, an integrated controller including the anti-lock braking system along with an active suspension is designed for a quarter car model, on the basis of the improved sliding mode control algorithm. Dynamical model of the active suspension along with the anti-lock braking system are derived using the Newton-Euler equations. Also, in order to model the friction between the tire and the road surface, the Pacejka model is used. The application of the control algorithm for the ABS yields a higher safety rate for the vehicles. On the other hand, the active suspension system beside the anti-lock braking system can improve the car safety and passenger comfort. To increase the friction between tire and the road surface, the active suspension system increases the normal force over the tire. Consequently, the performance of the braking system is improved with decreasing the stopping distance. In order to design the hybrid control system, the sliding mode control (SMC) system and proportional-integral-derivative (PID) controller are merged. In the PID-SMC strategy, the sliding surface is defined based on the PID algorithm. This novel control algorithm can decrease the chattering phenomenon besides shortening the stopping distance that yields the reduction of energy consumption.