The Remote Unmanned Work
System (RUWS), precursor to the Advanced Tethered
Vehicle, was designed to perform a variety of work tasks at ocean depths as
great as 20,000 feet (6100 m), giving it access to 98% of the ocean floor. 
The work
system itself included a hydraulically powered, master/slave arm with seven
functions including grip. The arm was terminus-controlled: the operator moved a
simple pistol grip to control the position and orientation of the remote
manipulator hand. It was also bilateral, or force-feedback: weights and forces
encountered by the remote arm were reproduced at a scaled-down level in the
master arm and thus felt by the operator. A second four-function arm or gripper,
simpler and more rugged, was used to steady RUWS with respect to the work or
work site.
The system actually
consisted of two vehicles. The second was a heavy Primary Cable Termination
(PCT) to which the work vehicle was firmly attached during deployment and
recovery, and which carried a cable reel for the 850 foot neutrally buoyant
portion of tether. The functions of the PCT were to maintain tension in the
primary cable, provide position-keeping capability to its bottom end, and to
launch and recover the RUWS vehicle itself. In affect, the PCT was a highly
sophisticated plumbob, keeping the main umbilical section vertical and isolating
the RUWS from its motions.
Another vital
component of the system was the Motion Compensating Deck Handling System
(MCDHS), an extremely versatile combination of launch crane and cable reel. Its
purpose was to launch and recover the RUWS vehicle/PCT combination and to tend
the primary cable, minimizing ship-induced motion and tension therein. It was
capable of operating in sea state three and recovery in sea state four.
RUWS was lost at sea in January of 1980. The cause was determined to be a
design flaw in the mechanical attachment to the PCT. Search efforts proved
futile due to the extremely rough scarp bottom. RUWS is currently undergoing
what is termed "long-term corrosion tests" at 13,500 feet depth approximate 15
miles West of Kona, Hawaii.
Address all questions/comments to: uuv-web@spawar.navy.mil
Last
update: 2 December 1998
