Title:
VEHICLE SPEED MEASUREMENT SYSTEM
Document Type and Number:
Japanese Patent JP2018146523
Kind Code:
A
Abstract:
PROBLEM TO BE SOLVED: To provide a vehicle speed measurement system that can more properly calculate an instantaneous vehicle speed.SOLUTION: A feature pattern is extracted that comes out in transition of a time between pulses during a period having a vehicle speed of an automobile fixed, and a number N of pulses during a period of the feature pattern is deemed to be a number of pulses during one revolution period. Further, regarding each integer i between integers from 1 and N, a ratio of an average of a time between all pulses in a revolution period of a prescribed number to an average of a time between an i-th pulse and an i+1-th pulse (where i+1 stands at 1 when i is N) in the revolution period of the prescribed number is calculated, and the ratio thereof is deemed to be a correction coefficient corresponding to between the i-th pulse and the i+1-th pulse. Then, thereafter, a measured time between the i-th pulse and the i+1-th pulse is corrected through multiplication of the corresponding correction coefficient by the time.SELECTED DRAWING: Figure 1
Inventors:
SEWAKI KOJI
Application Number:
JP2017044419A
Publication Date:
September 20, 2018
Filing Date:
March 08, 2017
Export Citation:
Assignee:
ALPINE ELECTRONICS INC
International Classes:
G01P3/489
Domestic Patent References:
| JP2000283990A | 2000-10-13 | |||
| JP2013213742A | 2013-10-17 | |||
| JPH06308139A | 1994-11-04 | |||
| JPS63172966A | 1988-07-16 | |||
| JPS5574463A | 1980-06-05 |
Foreign References:
| US20090012735A1 | 2009-01-08 |
Attorney, Agent or Firm:
Katsushi Sato
Masahiko Amagai
Kazuyuki Tachibana
Kyozo Katayose
Masahiko Amagai
Kazuyuki Tachibana
Kyozo Katayose