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EMB (Electro-Mechanical Brake) system that removes hydraulic brake device from conventional brake systems completely can be considered as BbW (Brake-by-Wire) system in the full sense. As the research on the EMB system is actively conducted, it is also required to establish the test methods for the performance verification and evaluation of developed EMB system. In fact, however, the characteristics of the EMB system makes it difficult to apply it to an actual vehicle test due to the expense and safety matters in the process of the test and evaluation. Thus, this study developed the EMB HILS (Hardware In the Loop Simulation) system in application of the actual EMB system in order to verify the actuating response characteristics and control logic performance of the EMB system before an actual vehicle test.

The automotive industry is replacing more and more hydraulic systems by electronic system. This not only reduces the weight of vehicles, but also has the potential for a large number of new features [1]. Such a change has led to researches on XbW(X-by-Wire) without the existing mechanical connection and hydraulic system, among which the study on BbW(Brake-by-Wire) in relation to brake devices proceeded to the point of EHB(Electro-Hydraulic-Brake) and then EMB(Electro-Mechanical-Brake). In replacement of existing CBS(Conventional Brake System) with EMB, various advantages such as improvement of response performance and easy combination with various brake applications including ABS and ESC have been found. In fact, however, the problem of fail-safe has remained. This study, therefore, is to develop the control strategy with which the vehicle's longitudinal and lateral motion can follow the driver's steering intention upon failure of one EMB actuator for braking in straight and corner.

The control logic of electronically controlled hydraulic brake system for hybrid vehicle is introduced in this paper. The hybrid brake system consists of the electronically controlled hydraulic brake system, electric motor and vacuum management system. The electronically controlled hydraulic brake system is developed and named as Advanced ESC system. This system has 14 linear valves, a motor, and multi-pumps. These linear valves are tested to find the dynamic characteristics, which is the relation between hydraulic force, magnetic force and spring force. By using this force relation, valve is controlled to be open or closed state. The multi-pumps are adapted to improve NVH and hydraulic pressure rise rates. After the regenerative brake torque of electric motor is studied, the control flow chart of this brake system is determined. During vehicle stop, the regenerative brake torque of electric motor gradually increases and then reaches to max torque to regenerate.

This paper proposes a control and fault diagnosis method for a pressure sensor based brake control system. The proposed wheel brake pressure control method consists of feedforward and feedback controller, respectively. The main purpose of the feedforward controller is to set the operating point of the feedback control, and the purpose of feedback controller is to improve the control response and the steady state error characteristic. Also, the proposed fault diagnosis method consists of three processes: a fault detection process, a fault isolation process and a fault identification process. In the fault detection process, a fault is detected by the difference between the estimated signal and the measured signal. Then, in the fault isolation process, the location of the fault is determined. Finally, in the identification process, the size and effect of the fault are evaluated.