This paper presents a method for estimating the spectra of water wave disturbances onfive of the six axes of a stationary, slender body underwater vehicle in an inertia dominated waveforce regime, both in head seas and in beam seas. Inertia dominated wave forces are typical ofthose encountered by a 21 inch diameter, torpedo shaped underwater vehicle operating in coastal waters and sea state 2. Strip theory is used to develop transfer function phase and magnitudebetween surface water waves and the slender body pitch, heave, and surge forces and moment for the vehicle in head seas, and for pitch, heave, yaw, and sway forces and moments in beam seas. Experiments are conducted which verify this method of transfer function calculation, anddemonstrate the effects of vehicle forward motion in the head seas case. Using known sea spectraand linear time invariant systems theory allows for estimation of the water wave disturbancespectra for these forces and moments.Application of sliding control techniques are then developed for the underwater vehicle longitudinal plane equations of motion. Computer simulations are used to demonstrate the dependence of underwater vehicle depth control upon the pitch control, and adaptive pitch controlis shown to provide good performance in the presence of substantial parametric uncertainty. Pitch disturbance rejection properties of variations of the sliding controller are investigated. Bothsingle frequency and stochastic disturbances are used, and the stochastic disturbance is developedusing the results of the earlier investigation.
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