| 摘要 |
PURPOSE:To exactly grasp calibration timing of an angular speed sensor by making timing of calibration at the time when it is judged that a vehicle is in a straight running state according to an advance azimuth detected by GPS navigation. CONSTITUTION:GPS azimuth data are input from a GPS receiver 1, if vehicle speed is Vkm (40km in general)/h or more from a vehicle speed sensor 2, it is judged that the azimuth data is highly precise and they are stored to RAM 9 as initial data D0. And successively the azimuth data are input, the other azimuth data input at this time (arbitrary i times) are compared with the data Do, if an absolute value of a difference between them is a specified angle 6 or less, it is judged theta that a vehicle is straight-running from the time of sampling, data Di. sampled at this time are N-th data (N: natural number) or judgement is performed on whether straight running of Vkm/h or more is detected continuously N times in the detection of the GPS azimuth and, if detection is performed N times, calibration 6 of an angular speed sensor 3 is performed according to the GPS azimuth data. |
