Supercavitation can significantly reduce skin-friction drag on an underwater body, thus enabling a dramatic increase in attainable velocity. The control of a High-Speed Supercavitating Vehicle (HSSV) poses unique challenges, since only small regions at the nose (cavitator) and on the afterbody (fins) are in contact with water and can be used as control surfaces. The interaction between supercavity dynamics and control surface actuation is complex and nonlinear. Experiments were conducted with a semi-axisymmetric, ventilated supercavity and a single wedge-shaped, 45 degree swept, cavitypiercing fin in the high-speed water tunnel at St. Anthony Falls Laboratory. Motion control was combined with water tunnel testing to create a hardware-in-the-loop system that can (a) provide critical hydrodynamic parameters for control models and (b) serve as a test bed for fin control strategies. Through a series of experiments, control surfacecavity interaction, cavity stability and hysteresis effects were studied. Fin torque (lift) was measured for different angles of attack with varying cavitation numbers. Closed-loop fin control experiments simulating simple maneuvers were carried out.http://deepblue.lib.umich.edu/bitstream/2027.42/84319/1/CAV2009-final146.pd
