EXAMINATION OF APPLICATION CONDITIONS OF UNDERWATER ACOUSTIC EQUIPMENT AND EFFECTIVENESS OF SENSING TECHNOLOGY FOR ADVANCED INSPECTION OF FISHING PORT FACILITIES

Abstract

 In the inspection of breakwaters and quays of fishing port facilities, most of the facilities are underwater and visual observation surveys by divers are mainly conducted, so the diagnosis results vary and lack objectivity, and a great deal of labor is required for the survey. It has been pointed out that it is necessary to improve and simplify the inspection method using sensing technology.

 The authors have used the narrow multi-beam and underwater 3D scanners of underwater acoustic equipment, which are part of the sensing technology, to show their effectiveness as inspection methods, as well as their accuracy and applicability. In this paper, we clarified the application conditions of both devices in a field test with the aim of introducing them into actual inspection work. We also proposed an inspection method using point cloud data using an underwater 3D scanner and image data using a UAV for inspection of offshore structures that are difficult to visually observe, and verified its effectiveness.