| 摘要 |
PURPOSE:To automate the setting of an initial position by storing constantly the present position which can be computed from an output value of an azimuth sensor and the present speed of a vehicle, and by using the coordinates of the present position as an initial position when a GPS receiver starts position measurement. CONSTITUTION:An amount of transfer from a starting point can be determined from the absolute azimuth found by an azimuth sensor 3 and from the present speed of a vehicle found by a vehicle speedometer 12, and the coordinates of the present position are fixed. These coordinates of the position are stored constantly, and when a GPS receiver 2 is powered on, the stored coordinates values are read to be used as the coordinates of an initial position for computation of a measured position. When prescribed position measurement computation is started, the result of every position measurement is used as a subsequent initial position, and the position measurement computation is conducted successively in this way. This method enables the automatic setting of the initial position for the GPS receiver 2. |
