| 摘要 |
PROBLEM TO BE SOLVED: To highly precisely estimate a vehicle speed without wiring connection with a vehicle ECU and a vehicle speed signal, even when radio waves of a GPS satellite is insufficient by utilizing the accumulated value of an acceleration value acquired from an acceleration sensor and an amount of changes in position data by a GPS, for navigation technique. SOLUTION: An accumulating section 11 acquires a value corresponding to the acceleration of a vehicle or a value, as an acceleration, to calculate its accumulated value. A vehicle speed calculating section 12 calculates the vehicle speed from the amount of change in position acquired by the GPS, and a recording section 13 records as associated data D into a recording medium section 5 by associating each pair of the accumulated values and the vehicle speeds at the same time. An estimating processing section 14, when a receiving condition of satellite radio waves in the GPS, refers to the associated data D based on the present accumulated value to estimate the present vehicle speed by the vehicle speed related by the same accumulated value or its approximate value. COPYRIGHT: (C)2007,JPO&INPIT |
