Abstract: An acoustic data acquisition system for shipboard use is disclosed that allows for underwater acoustic data measurements at preselected submerged marine structural coordinates using a free swimming, quiet dynamically positionable remotely operated vehicle (ROV). Moreover, the disclosure provides a method of performing acoustic data acquisition with an ROV by first inputting the marine structural features by use of a computer aided design subsystem, determining the required trajectory path and hovering coordinates for data measurements, next, establishing the acoustic telemetry system for the remotely operated vehicle's control system to operate within and make an absolute positional fix to the marine structure's coordinates then, establish the ambient acoustic conditions of the worksite. The system is monitored and controlled from a computer based system.

Abstract: An improved integral marine propulsion unit is disclosed that can generate a thrust vector in any of three degrees of motion. The unit utilizes both collective and cyclic propeller blade pitch angle variation to generate these thrust. This unit obviates the need for control surfaces and rudders for motion control of a marine vessel. Additionally, this unit provides flexibility in external propulsor arrangements on a marine hull. The unit integrates the swash plate mechanism and actuators within the central bore of a ring type prime mover.