An Investigation Of Vehicle Anti-lock Braking System Based On Adaptive Sliding Mode Control Method

The study of the control methods is one of the most important problems of the Anti-lock braking technologies. The adaptive sliding mode control, which combines sliding mode variable structure control and adaptive control reasonably, is a new strategy solving control problems comprising uncertain parameters or time variable parameters. The control method has suitable application in anti-lock braking system (ABS), due to overcoming the deficiencies of the high frequency chattering near the switching surface adopting sliding mode control and the weak Robust applying adaptive control.The research scope of this paper includes:â‘ According to the practical requirements, the 9 degrees of freedom vehicle braking model, the 3 degrees of freedom dual-wheels braking model, the 2 degrees of freedom single-wheel braking model, adhesion coefficient - slip-ratio model, the hydraulic pressure detent model are founded.â‘¡Measurement and process of the wheel speed signal are studied in detailed, and the method of acquiring velocity based on the accelerated sensor is elucidated.â‘¢This thesis presents a parameter adaptive sliding control algorithm based on the analysis of zero-order and one-order switching sliding mode control algorithms for the non-linear control model of ABS. The stabilization of parameter adaptive sliding control algorithm is testified, which ensures the reachability of system sliding mode condition during restricted hours. The adaptive sliding control algorithm is compared with the other two algorithms using MATLAB. The results of simulation verify that the adaptive sliding mode algorithm has the advantage of the capability of braking and the order of system input.â‘£An ABS real-time loop experiment platform is framed,and its software, which mainly consists of the whole algorithm of the MATLAB node, the velocity signal process algorithm and the iterative algorithm of the adaptive sliding mode control method, is designed by applying the MATLAB node of LabVIEW. The validity and feasibility of ABS parameter adaptive sliding mode control method proposed in this paper has been validated by means of the analysis of the experimental results.The investigation of ABS based on adaptive sliding mode control has referenced value to a certain extent for the further development and improvement of ABS.