Abstract: Disclosed is a creeper for movably supporting a reclining worker in confined space on a variety of ground surfaces. The creeper includes a body platform; at least three wheels rotatably mounted relative to the platform for rolling ground contact whereby the platform is movable by the worker above the ground surface. Each wheel has a circumferential outer rib, preferably having an outside diameter not less than approximately 5 inches and a rib width not greater than approximately 1.5 inches for smooth rolling contact with the ground surface when the ground surface is hard and flat; and a plurality of side ribs laterally extending on opposite sides of the outer rib, the side ribs collectively having a major diameter preferably not less than approximately 1.4 inches greater than a minor diameter of the ribs, the outside diameter being between approximately 0.1 inch and 0.6 inch greater than the major diameter.

Abstract: One or more buoyancy engine units utilizing buoyancy motive force (BMF) are herein defined. For relatively deep fluids a plurality of buckets hinged together mouth to bottom with a gas tight seal between said buckets forming an endless chain can rotate over sprockets attached to parallel shafts spaced apart to control chain tension as either shaft delivers buoyancy motive force (BMF). Each buoyancy engine unit will produce continuous duty rotation and thereby power when the receptacles are alternately filled with gas and then the fluid in which they are submerged.