Abstract:

Brake safety is one of the key technologies for vehicle active safety. Braking decision and actuator control are two main factors that affect the performance of the brake by wire system. Road surface adaptability and controller robustness have important influence on braking decision and actuator control respectively， restricting the development of brake by wire system. In this paper， based on a hydraulic brake by wire system， a double-layer structure brake system controller is proposed to solve the problems of road surface adaptability and controller robustness. The upper layer uses computer vision to identify the type of road surface， and formulates the optimal slip rate of the current road surface according to the recognition result； the lower layer introduces the sliding mode control theory in track and control of the optimal slip rate during the braking process to solve the problem of brake system parameters uncertainty. Through simulation and experimental verification， the results show that the double-layer structure brake system controller has better road surface adaptability， shorter braking distance and better controller robustness than the traditional controller.

Key words: computer vision, double-layer structure controller, road surface adaptation, brake by wire, pressure control