Title:
DRIFT CANCELING DEVICE FOR ON-VEHICLE GYROSCOPE
Document Type and Number:
Japanese Patent JP3412092
Kind Code:
B2
Abstract:
PURPOSE: To cancel the DC-level drift of a gyroscope so as to make the gyroscope to output accurate signals by sampling the levels of detected signals only when the differences between the levels of the detected signals and the zero level of a prefixed signal are equal to or smaller than a threshold.
CONSTITUTION: The signal output of a piezoelectric vibration gyroscope 11 is inputted to a microcomputer 18 through amplifiers 14 and 15 after a reference voltage from a reference voltage source 12 is subtracted from the signal output at a subtractor 19 and the output of a D/A converter 16 is subtracted from the signal output at another subtractor 1B. The microcomputer 18 samples the levels of detected signals only when the differences between the levels of the detected signals and the zero level of a prefixed signal are equal to or smaller than a threshold by repeatedly referring to the levels of detected signals within a prescribed period of time and calculates the average level of a plurality of levels. When the difference between the calculated average level and zero level is larger than a prescribed value, the microcomputer 19 corrects the zero level based on the average level. Since the zero level is always corrected and controlled in such a way, such a signal that the drift of it still level is offset can be outputted.
Inventors:
Seiji Ishikawa
Tomohiro Yamamoto
Yuichi Murakami
Tomio Hota
Tomohiro Yamamoto
Yuichi Murakami
Tomio Hota
Application Number:
JP7843094A
Publication Date:
June 03, 2003
Filing Date:
April 18, 1994
Export Citation:
Assignee:
Aisin Seiki Co., Ltd.
International Classes:
G01C21/00; G01C19/56; G01C19/5776; G01C21/28; (IPC1-7): G01C19/56; G01P9/04
Domestic Patent References:
| JP3191812A | ||||
| JP462419A | ||||
| JP3279809A | ||||
| JP238916A | ||||
| JP743165A | ||||
| JP63182519A | ||||
| JP60183518A |