Instrumentation for the measurement of shallow seabed topography by a fishing echo sounder

The multi-beam bathymetry can provide a detailed view of the seafloor and is successfully utilized in oceanography; however its expense makes it impractical for many uses. In this paper, the authors present a low-priced system for surveying shallow sea bottom topography by using a fishing echo sounder in such a way that the many areas of the industry in which the information of the sea depth is required can use it easily get the information they need. The system is based on sensor network technology, namely Micro Cube, which allows for the collection of the data from the fishing echo sounder via the Internet. In this paper, the planning of the system is presented and the experiments on the west coast of Hokkaido, Japan are discussed to show the accuracy and to demonstrate the applicability of the present system. Measurements generated by the proposed system are in good agreement with the measurements observed by the multi-beam echo sounder, Sea Bat, with accurately positions data using Star Fire (high performance differential GPS sensor). Since the Micro Cube is easily connectable to other standard digital-equipment which is common among fishing vessels in the inshore fishery and exploits them as sensors to collect marine information, other useful real time sensor applications are anticipated in the fishing industry.