Abstract: A underwater mobile type inspection system is disclosed wherein said system comprises a multi-articulated manipulator with a probe attached at its tip end thereof. A pivot base supports the proximal end of the manipulator for free rotation and is provided with a propulsion device. An anchoring base is attached to the bottom of said pivot base via a pivot driving mechanism. An adhesion device and a mobile vehicle device are provided, both of which are mounted on the outer periphery of said anchoring base. The inspection system may be applicable to a defect finding operation, other inspecting procedures, cleaning and recovery operations of foreign materials in large-sized vessels, such as nuclear reactor pressure vessels, water pools and storage tanks etc.

Abstract: An improved position detecting apparatus for detecting the position of an underwater moving body loaded with an inspecting device is provided. The apparatus is such that it makes it possible to perform inspection of a structure in water quickly, reliably and with high precision. The improvements reside in that the apparatus comprises a light source and a corner cube mounted on the underwater moving body in combination to serve as a target, a follower device, which includes a visual sensor for catching light emitted from the light source, for automatically following the target, an underwater argon laser length measuring instrument for measuring a distance between a length measuring head integrated with the visual sensor and the corner cube, and a detector device for detecting the position of the underwater moving body on the basis of an azimuth angle of the target obtained by the follower device, a reference of one side of a triangle and the measured distance.