Abstract: A marine unit has an elongate payload-containing body, a plurality of legs each connected by a pivot at its inner end to the lower end of the body, and an actuator in the body for deploying the legs to cause the body to stand upright on the sea bed. The actuator is a double-acting constant displacement piston and cylinder arrangement connected to each of the legs by a link. The link is connected to the piston by a second pivot and to the leg by a third pivot, the geometry of the three pivots being such that the linkage is self-locking and reverse loads on the leg are not transferred to the actuator.

Abstract: A marine unit for location on the sea bed has a cylindrical body and legs which are connected to the body by a pivot adjacent one end of the body. Each leg has a toothed member which engages a common worm driven by a motor. The legs are connected by webs of net. The body and nets nest within the legs for storage, the legs are partly opened for the descent, and are opened fully when the unit reaches the sea bottom to support the unit with its axis approximately vertical.