JPS57135377A - Relative position detecting device - Google Patents

Abstract

PURPOSE:To detect, for instance, the depth of a marine structure which is in sailing, an angle made against a vertical axis, and a correct lateral range, by placing a transmitter-receiver and a receiver on the vertical axis at constant intervals, and utilizing a time interval between a transmitting sound from the transmitter-receiver and a reflecting sound from a reflection body. CONSTITUTION:A transmitter-receiver 2 and a receiver 3 placed on a marine structure A are vertical on a vertical axis 7 at an interval (a). A transmitting sound F having constant frequency and constant pulse width, transmitted from the transmitter-receiver 2 is reflected by a reflection body 4 of other marine structure B, and a reflected wave is received as a receiving sound by the transmitter-receiver 2 and the receiver 3. Distances r1, r2 between the transmitter- receiver 2 and the receiver 3, and the reflection body 4 are calculated from a time interval of said transmitting sound F and the receiving sound. Also, an angle theta linking the axis 7, the transmitter-receiver 2 and the reflection body 4, and relative depth (z) of the transmitter-receiver 2 and the reflection body 4 are circulated from the distances r1, r2 and the distance (a). Furthermore, a correct lateral distance Y of the marine structure B against the marine structure A is derived by utilizing the sailing of the marine structure B.