The NaviComputer: a portable long baseline navigation system designed for interface to an autonomous underwater vehicle

There are a number of systems that can be used to navigate an autonomous underwater vehicle (AUV). These include GPS, bottom locked Doppler systems, and a variety of compass technologies. However these all have their limitations, and their individual specifications may be degraded when incorporated into a full-up AUV navigation system. In contrast, long baseline navigation is accurate and repeatable, however the complexity of its implementation has kept it from being utilized more often. The paper describes the hardware and software developed for a new, self contained, long baseline system designed for implementation in an AUV. Based on the proven REMUS AUV navigation system, it is small, low power, and has a simple NMEA-183-like serial interface. In addition, a Windows program that interfaces to this system has also been developed. This allows the performance of the system to be tested and verified outside of the AUV, thus simplifying the task for integrators and developers. The results of performance tests in Woods Hole harbor are discussed. The paper describes the system, discusses both software and hardware issues in its development, and its integration into Lockheed-Martin's CETUS II autonomous underwater vehicle.