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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.

This paper focuses on clamping force control of electronic wedge brakes without additional sensors for cost-effectiveness and system simplicity. Brake-by-wire systems can be used for enhanced, safe braking of intelligent and environmentally friendly vehicles such as gas-electric hybrid and electric vehicles. For implementation of the electronic wedge brake, the clamping force should be controlled properly even though model uncertainty and parameter variations exist due to the environment or system characteristics changes, e.g., temperature variations, pad wear, and nonlinear friction. In this paper, the electronic wedge brake is modeled to include the wedge dynamics as well as the nonlinearities such as backlash and friction in mechanical connections and clearance between the brake disk and pad. An on-line status monitoring algorithm using the simplified mathematical models is designed to estimate the mechanical system parameters.

In future automobiles, conventional hydraulic brakes can be removed and be replaced by electrically operated brakes called brake-by-wire. The brake-by-wire units such as EMB(Electro-Mechanical Brake) provide better performance in braking by directly controlling the brake motor and are environmentally friendly without hydraulic fluid. Since the brake is safety-critical, the EMB should be reliable in its lifetime and robust fault diagnosis techniques should be included. Many researches have been carried out to develop the diagnosis techniques to improve their robustness and reliability. In this study, a fault size detection method is proposed with the parity space approach for the EMB system. In order to detect and isolate sensor faults from the residual, the residual generator is constructed. The model-based fault diagnosis system is developed for the EMB sensors; current sensor, position (or speed) sensor and clamping force sensor.

Electro-Mechanical Brake (EMB) systems can provide improved braking and stability functions such as ABS, EBD, TCS, ESC, BA, ACC, etc. For the implementation of the EMB systems, reliable and robust fault detection algorithm is required. In this study, a model-based fault detection algorithm is designed based on the analytical redundancy method in order to monitor possible faults in EMB systems. The performance of the proposed model-based fault detection algorithm is verified in simulations. The effectiveness of the proposed algorithm is demonstrated in various faulty cases.