Nonlinear Backstepping Design of Anti-lock Braking Systems with Assistance of Active Suspensions

This paper develops a nonlinear anti-lock braking system combined with active suspensions applied to a quarter-vehicle model by employing nonlinear backstepping control design schemes. An anti-lock braking system must have the potentials to release the wheel-locking situation and assist the car to stop at shorter distance. Although the braking distance can be reduced by the control torque from disk/drum brakes, the braking time and distance could be further improved if the normal force generated from active suspension systems is considered simultaneously. As a result, the integration of anti-lock braking and active suspension systems indeed possesses the ability to enhance the system performance because of reduction of braking time and distance. Furthermore, some comparative simulations are given to illustrate the excellent performance of our integrated anti-lock braking system.