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Inertially Aided Navigation of Undersea Vehicles

As the tasks to be performed by underwater vehicles become more sophisticated, the navigational requirements and positional-accuracy constraints become more rigorous. A number of proposed missions for manned and autonomous vehicles require that the position be accurately known at all times, independent of external navigational input data. A typical cruise duration might extend from several hours to several hundreds of hours. Inertial navigation systems have been proposed to assist in the solution to such underwater navigational problems. This paper will review the current state of development of inertial navigation systems (INSs) with respect to accuracy, power requirements, operational constraints, size and cost. Systems may be grouped into operation-specific categories as a result of these limitations. Recent technological developments, including ring-laser and fiberoptic gyros, will be briefly discussed along with their future applicability to undersea navigati on requirements.