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A new control algorithm of a wedge brake system has been developed. The proposed control algorithm is based on the position control and current control of electronic wedge brake(EWB). The EWB control system in rear wheel has both active braking functions like ABS and ESC and convenient function such as EPB. In this paper, development of control algorithm was performed using hybrid brake system(HBS) which consists of hydraulic brake in front wheel and electronic brake in rear wheel. At first, the configuration of EWB system is explained. Next, structure of electronic control in HBS is explained. And then ABS/ESC/EPB control algorithms are shown. ABS control algorithm has wheel slip calculation, wheel error calculation, wheel slip control, position control, current control, and duty control. ESC algorithm consists of yaw error calculation, yaw moment control, wheel slip control, position control, current control, and duty control.

Lane keeping assistant system (LKAS) is expected to reduce the driver workload with assisting the driver during driving and is regarded as a promising active safety system. For the proposed LKAS which requires cooperative driving between driver and the assistance system, a Model Based Predictive Controller (MBPC) is proposed to minimize the effect of system overshoot caused by the time delay from the vision-based lane detection system. In order to validate the proposed LKAS controller, a HIL (Hardware In the Loop) simulator is built using steering mechanism, single camera, torque motor, sensors, etc. The performance of the proposed system is demonstrated in various roadways.

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.