| Today with demands rising to driving safety, the functional scope of brake system has been expanded widely. The traditional brake system behaves more and more disadvantages. Then a new sort of brake system -- Electromechanical Brake System (EMB) was invented.The EMB (so called brake-by-wire) has advanced capability. The advantages such as no brake fluid, desponding quickly, reliable capability, safe and propitious to environment protecting give EMB an exciting future and market value. In the domestic, the researches of EMB are begun only several years ago. Several companies such as Bosch, Siemens and Teves have developed some EMB models, but the researches are still blank in China.To research the control strategy of EMB, a test-bed was established. One test line was also set up which begins with acquiring the brake desire of driver, ends with generating the brake force. The test line includes four segment: Brake desire generating part, which acquiring the real-time brake desire of driver with a displacement sensor installing on the axis of brake pedal; Driving circuit part: a center control circuit was devised that mainly comprises a MCU—C164CI of Infineon company, as well as a motor driving circuit consist of an integrate circuit—LMD18200 of National Semiconductor company. The software programming related to C164CI was finished; Power output part: using a torque motor simulates the actuator of EMB to output brake torque; Torque checking part: using a torque sensor to check motor torque, according the data to evaluate control effect.When test-bed beginning to work, the brake pedal displacement signal is sent to center control circuit mainly comprising a MCU—C164CI. After the signal was deal with by C164CI, PWM signal was output and given to motor driving circuit; drive the torque motor to generate the needed torque. The function was achieved that acquiring the real-time brake desire of driver to control the motor torque in linearity rule according to the displacement of brake pedal.
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