Abstract: A vane type hydraulic motor which is operable with seawater as the hydraulic fluid for undersea diver use. The motor is compact, lightweight and is lubricated by the seawater working fluid. The motor uses corrosion resistant materials with the requisite flexibility, mechanical strength, friction characteristics and low swelling rate when immersed in seawater. The motor structure provides durable seal means and pressure balanced operation which minimizes wear. The vane structure permits easy sliding vane movement, and uses the seawater pressure to control vane movement and sliding seal capability.

Abstract: A hand controller having a control handle member supported by a hexagonal array of three pairs of oppositely-angled force sensors provides for creation of control signals according to degree of input manual effort in any and all linear and rotary directions: left; right; up; down; fore; aft; forward; rearward; leftward and rightward; tilt moments; and clockwise and counterclockwise yaw moments.

Abstract: Apparatus for supporting the life, safety, comfort, and usefulness of an underwater diver by pumping seawater, or other ambient water in which the diver may be located, under pressure from a surface site to the submerged diver site, and locally converting by hydraulic friction at the diver site the hydraulic energy of such pressurized pumped seawater into diver-warming heat or/and mechanical energy for operating tools, pumps, etc.

Abstract: Breathing apparatus which incorporates a sensing device operable to adjust the amount of breather's exhaled gas captured in a gas collector section as a direct function of the carbon dioxide content of the exhalation. The amount of exhaled gas captured is sufficiently low in carbon dioxide (CO.sub.2) content to permit rebreathing on the next inhalation, at which time the sensor again adjusts the volume of exhaled gas to be captured. In the one embodiment, a fire fighter's breathing system is described wherein the gas collector section is integral with the breathing mask worn by the fire fighter.

Abstract: Breathing gas from a remote source is supplied directly to a diver's helmet, without the requirement of a demand valve. Exhaust gas is returned back to the remote source through a series arrangement of a normally open fail-safe valve and an exhaust control valve which maintains the helmet pressure within predetermined limits relative to the ambient water pressure. Should the exhaust control valve fail in the open position, the fail-safe valve will actuate to insure that the helmet pressure does not decrease to a dangerous level. Valve actuation is a function of diver orientation so as to maintain helmet pressure within a range to minimize diver breathing effort, for the various positional orientations.The helmet includes ducting for the exhaust gas and the valves are constructed and arranged to sense the helmet pressure directly for comparison with the ambient water pressure acting on the respective valves.

Abstract: Underwater breathing apparatus which includes means for reducing the power required to operate the pumps that effect flexible-hose interchange of breathing gas to and from a diver and a diving bell. This is accomplished primarily by maintaining a substantially constant differential between the supply and return pressures.