| 摘要 |
PURPOSE:To measure accurately the position of a moving body, by combining a sound wave transmitter mounted on the moving body and a fixed sound wave receiver. CONSTITUTION:A sound wave transmitter 1 is mounted on an unmanned car and transmits a signal modulating a carrier wave with periodic signals in the form of a sound wave. The sound wave receivers 21-2x are located in <=3 units at different still positions where the moving range of the unmanned car is able to be directly viewed. The signals received at receivers 21-2n are supplied to a selector 3, and the signals of three channels, e.g. i-R are selected by a command given from a computer 5. For these selected signals, the respective differences in phase are obtained through phase difference measuring circuit 41 and 42. Afterwards, these signals are transmitted to the computer 5. The computer 5 calculates the position of the unmanned car from the phase difference and the distance between the respective receivers. In such way, the position of a moving body is accurately measured. |
