| 摘要 |
PURPOSE:To quickly derive position coordinates of many points by one person, by transmitting and receiving an acoustic wave and an electromagnetic wave among three or more points where a position coordinate is known and a derived point position, and measuring its time. CONSTITUTION:A reference point device 4 is placed in three points where a position coordinate is known, and a point deriving device 8 is installed at a point position to be derived. In this state, an electromagnetic wave is transmitted from an electromagnetic wave transmitter 5 of the point deriving device 8, and received by an electromagnetic wave receiver 2 of a reference point device 4. This receiving time is measured by a timer 3, and after a prescribed time, an acoustic wave is transmitted from an acoustic wave transmitter 1. This acoustic wave is received by an acoustic wave receiver 6 of the point deriving device 8, and the receiving time is measured by the timer 3. A computing element 7 derives a point position to be derived from this receiving time. A temperature sensor 10 always measures a temperature and executes a temperature correction of the acoustic wave.
|
