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Experimental evaluation of new methods for in-situ calibration of attitude and doppler sensors for underwater vehicle navigation

This paper reports the development and in-water experimental evaluation of two new methods for the problem of in-situ calibration of the alignment rotation matrix between Doppler sonar velocity sensors and gyrocompass attitude sensors arising in the navigation of underwater vehicles. Most previously reported solutions to this alignment calibration problem require the use of absolute navigation fixes of the underwater vehicle, thus requiring additional navigation sensors and/or beacons to be located externally and apart from the underwater vehicle. We report two alignment calibration methods employing only internal vehicle navigation sensors for velocity, acceleration, attitude, and depth. Results from laboratory experiments comparing these methods to previously reported techniques indicate satisfactory performance of the proposed methods.