JOURNAL OF MECHANICAL ENGINEERING VOL. 1, NO. 1, JANUARY 2012 4 Abstract—In the present paper the performance of the self- reinforcement Electronic Wedge Brake system (EWB) which is one of the Brake-By-Wire applications used on motor vehicles has been investigated. A simulation has been developed by building a prototype for the wedge brake construction and the electric control system. The measuring sensor is represented by e- pedal with a potentiometer, the controller is a power supply board and the actuator is a DC motor attached to a roller screw. As the driver presses the e-pedal a certain value of electric resistance will be generated; this controls the DC motor speed and consequently affects the output measurements which are the wedge displacement that pushes the brake pad to generate the braking force required to stop the wheel. The simulation has been extended and a mathematical model created to simulate the full electronic wedge brake system containing the components (DC motor, Roller screw and Wedge brake construction). The mathematical model has been applied on MATLAB program simulink file considering system inputs and outputs for studying the brake system performance. The input variables are the caliper stiffness and the wedge mass. A PID control methodology also has been applied to the system to monitor the system behavior with and without the controller. All the results of the practical and the theoretical investigation are presented and discussed to conclude the better operating conditions of the system. Key words: Electronic Wedge Brake, Brake-By-Wire, PID control, caliper stiffness, I. INTRODUCTION As an alternative to fully hydraulic brakes so called brake-by- wire systems have been discussed recently. In these brakes the applied force will be generated at the wheels by actuators. The principle of brake by wire is based on separating the hydraulic connections between the brake pedal and the wheel brake and replacing it with electrical signals. The function of Manuscript received January 17, 2011. M. A. A. Emam, Automotive Engineering Department, Faculty of Engineering - Mataria, Helwan University, Cairo. Egypt. (E-mail address: mohemam_70@yahoo.com). A.S. Emam, Automotive Engineering Department, Faculty of Engineering - Mataria, Helwan University, Cairo. Egypt. (E-mail address: ashraf_galab@yahoo.com). Samir M. El-Demerdash, Automotive Engineering Department, Faculty of Engineering - Mataria, Helwan University, Cairo. Egypt. (E-mail address: samireldemerdash@yahoo.co.uk). Sayed M. Shaban, Automotive Engineering Department, Faculty of Engineering - Mataria, Helwan University, Cairo. Egypt. (E-mail address: shaabansayed@rocketmail.com). M. A. Mahmoud, Automotive Engineering Department, Faculty of Engineering - Mataria, Helwan University, Cairo. Egypt. (E-mail address: mahmoud_abd_elbaky@yahoo.com). the brake by wire is compatible with other electronic systems such as Anti-lock Braking System (ABS). The driver desire to brake the vehicle is recognized by sensor that delivers a signal according to the pedal stroke which is transmitted to the brake controller. The brake controller then generates signal to the wheel actuator. Fig. 1. Simple model for the wedge brake concept [1] Figure (1) illustrates a simple model of wedge brake concept. The brake lining is equipped with a wedge on its backside which is rested on an abutment; the actuator presses the brake lining in between the abutment and the brake disc with the motor force  . The braking force    resulting from the contact between the brake disc and the brake lining acts in the same direction as the motor force which results in the anticipated self-reinforcement. By comparing the Electronic Wedge Brake with the convention brake, the braking force generates according to wedge will be much higher than the convention one which consequently affects the stopping distance to be shorter in wedge system than the convention system. Performance of Automotive Self Reinforcement Brake System M. A. A. Emam, A.S. Emam, Samir M. El-Demerdash, Sayed M. Shaban and M. A. Mahmoud