| 摘要 |
PROBLEM TO BE SOLVED: To detect a brake noise with a simple configuration without requiring a special purpose sensor, such as a vibration sensor. SOLUTION: Wheel speed sensors 7a to 7d output alternating current signals according to the rotational speed of brake rotors of the respective wheels 6a to 6d. An electronic control unit (ECU) 3 calculates the wheel speed based on the alternating current signals. The obtained wheel speed signals include a constant wheel speed value which does not depend on time and a variable wheel speed value which fluctuates according to the generation of the brake noise. Frequency components corresponding to the brake noise can be extracted by carrying out the FFT (fast Fourier transform) for the wheel speed including the variable wheel speed value. When the extracted frequency components exceed a required value, it is judged that the brake noise has been generated. Therefore, the brake noise can be detected by means of the wheel speed sensors used in the antilock brake system (ABS) control without using a vibration sensor, etc. COPYRIGHT: (C)2005,JPO&NCIPI
|
