| 摘要 |
<p>A method of seafloor survey using a pontoon moving at short time intervals on the surface of a deep sea of strong tidal current, which can be applied economically and accurately in a simple constitution requiring a smaller sea surface area, as compared with a conventional method. To attain this method, a plurality of omnidirectional screw propellers (42) are provided on the bow and stern of a self-propelling pontoon (30). The motors (43) for these propellers (42) are controlled by a position controller (49) comprising position measuring unit (45), gyrocompass (46), an anemoscope-anemometer (47) and a control arithmetic unit (48), whereby the self-propelling pontoon (30) is automatically retained in a predetermined site. After a casing pipe (12) has been fixed to the self-propelling pontoon (30) via a pipe support unit (29) and extended and set up substantially perpendicularly on a survey site, a boring machine (13) is driven as the self-propelling pontoon (30) is retained on a predetermined site by an automatic retaining system, in order to excavate the sea bottom (10) by a boring pipe (14).</p> |
