Title:
STRANGE SOUND JUDGING APPARATUS AND METHOD THEREFOR
Document Type and Number:
Japanese Patent JP3885297
Kind Code:
B
Abstract:
PROBLEM TO BE SOLVED: To enable quantitative judgment of a strange sound due to non-steady vibration, based on a vibration data of judged object during the vibration by a vibrator.
SOLUTION: A test vehicle 1 is vibrated by a vibrator 2 and vibration in the vehicle is detected by a microphone 3 installed in a room of the test vehicle to input a vibration data into a judging means 4. A judging means is so arranged to separate the vibration data into a normal data and an abnormal data with an abnormal data discrimination part 41 and the normal vibration data is inputted into a time frequency analysis part 42. In a frequency analysis part, a smoothing Wigner distribution is formed and at an instantaneous intensity computing part 43, the smoothing Wigner distribution is totalized in the direction of frequency to find a instantaneous intensity of vibration. At a data extraction part 44, a part of the smoothing Wigner distribution is extracted corresponding to time at which the instantaneous intensity of vibration exceeds a fixed value and the results are totalized in the direction of time to obtain a strange sound frequency distribution.
Inventors:
Uchida, Hiroshi
Ueda, Koji
Ueda, Koji
Application Number:
JP1997000179440
Publication Date:
December 01, 2006
Filing Date:
July 04, 1997
Export Citation:
Assignee:
MAZDA MOTOR CORP
International Classes:
G01H17/00; G01M7/02; G01H17/00; G01M7/00; (IPC1-7): G01M7/02; G01H17/00