An Acoustic Sub-Sea Navigation System

The need for a highly accurate subsurface acoustic navigation system has been demonstrated in a number of work situations including offshore structural inspection. This paper describes a microprocessor controlled transponder-hydrophone system capable of producing the three dimensional position coordinates and heading of the autonomous submersible vehicle, called EAVE. The position and heading are calculated with respect to a specific coordinate system fixed by the location of sub-sea anchored acoustic transponders. A dual-processor hardware configuration will be discussed and the means by which position data is collected will be examined. The navigation algorithm will be described and the means by which accurate position coordinates are extracted from the ray data will be discussed.