UNDERSEA TECHNOLOGY 57 



Propeller Systems for Submersibles 



To date, several propeller and thrust-producing components have been 

 developed for naval appUcation. They include conventional thrusters, 

 such as stern propellers and propellers mounted within a pod, and also 

 fluid thrusters, such as water jets. At present, the technology and design 

 capability is available to develop an advanced propeller concept, the tan- 

 dem propeller. Future submersibles performing work tasks will need to 

 be able both to maintain depth position and to exert with precision large 

 forces and moments. Development is planned of the tandem propeller 

 concept for providing submersibles controlled thrust in the six degrees 

 of freedom. 



Developments to provide reUabiUty in electrical components are under- 

 way in critical areas such as electrical hull penetrators, electric cabling, 

 underwater connectors, insulating materials, and fluids and encapsulation 

 materials for use in a high pressure sea water environment. Usable examples 

 of each of these components have been successfully tested in the environ- 

 ment by the bathyscaph TRIESTE to about 8500 ft, but reliability re- 

 mains a goal which must be achieved to provide for operational safety. 



UNDERSEA MANIPULATORS 



The first manipulator fitted to a Navy manned submersible was a modi- 

 fied nuclear hot-cell mechanical arm. This manipulator was used on the 

 TRIESTE I and in 1963 recovered a piece of pipe from the submarine 

 THRESHER in 8500 ft of water. The arm was oil filled and pressure 

 compensated to exclude sea water. It was designed to handle weights up 

 to 50 pounds at a 39 in. reach with a two-jaw clamping grip. All motions 

 of the manipulator were powered by electric motors. 



The TRIESTE II manipulator had a lift capacity of 500 pounds at a 

 reach of 10 ft. It was hydrauhcaUy actuated by a remotely controlled 

 external hydrauhc system mounted on top of the float structure. Because 

 of TRIESTE II's arrangement, the manipulator was mounted aft of the 

 personnel sphere and viewed with the aid of a television camera. 



With knowledge gained from the efforts on TRIESTE I and II as a 

 basis. Navy turned to industry for a study to integrate the operator, the 

 controls, manipulators, tools, and viewing aids into a coordinated system. 



Using this study the manipulators were designed for the AUTEC ve- 

 hicles. These vehicles, now under construction, will have a pair of arms 



