Application is a hydraulically operated lift mechanism to position a large (4x8 foot) mirror for underwater photography in a towing tank used for scale model testing. The mirror normally sits flush with the tank floor, but is hinged along one of the long edges, and can be raised up to a 45 degree angle by a hydraulic motor and acme screw "scissor jack" mechanism recessed into a shallow pit under the mirror. The tank itself is essentially a swimming pool 8'deep, 16'wide, and 312'long.
Linkages to the surface will be difficult, as nothing can be run through the water column above the mirror, as it would interfere with the tests being run. There is a 3" PVC conduit between the pit and the outside of the tank (above waterline), to be used as a chase for the hydraulic hoses and limit switch wiring.
I need limit switches to detect the end of travel in both directions, to avoid overtravelling the device and twisting the frame/cracking the mirror.
This mirror mechanism is just ONE of the strange projects I am involved with these days. The hydrodynamics laboratory I work for is in the process of a major renovation/upgrade, and myself and our machinist are responsible for just about all the specialized apparatus needed. This includes a large servohydraulic wavemaker, 125 HP towing carriage drive with .01% speed repeatability, 300' long flexible cable carriers for power and instrumentation to a moving carriage, and racks of support electronics/signal conditioners, all tied together with literally miles of low voltage signal and control cabling.
Hope to get some pics of the neater stuff and post them here on ECN.
PS, as far as maintenance is concerned, we have SCUBA divers on-staff for the minor stuff, and the tank gets drained about once a year for regular PM.
[This message has been edited by NJwirenut (edited 06-23-2006).]
