According to the present invention there is provided an underwater vessel comprising: a body; a thruster operable to produce thrust, wherein the thruster is deployable from the body; an actuator assembly connected to the thruster and operable to deploy the thruster, wherein the actuator assembly is operable to deploy the thruster in a first configuration in which the thruster is oriented to produce a thrust having a vertical component when the thruster is operated.

A variable buoyance engine includes a pressure vessel, a reservoir, an external bladder, a non-compressible fluid inside the reservoir and the external bladder, and a drive system. The drive system includes a shape memory alloy actuator, a piston attached to the actuator, a power source connected to the actuator, and a controller configured to control application of power to the actuator. The power source is configured to cause the actuator to change temperature and deform when power is applied to the actuator thereby moving the piston from a first position to a second position. The reservoir and external bladder are configured to retain, without leakage, the non-compressible working fluid. The external bladder is configured to receive the non-compressible working fluid from the reservoir when the actuator moves the piston from a first position to a second position to create a second, positive buoyancy state and to expel the non-compressible working fluid from the external bladder to the reservoir when the actuator moves the piston from the second position to the first position to create a first, negative buoyancy state.

An autonomous underwater vehicle, which includes a hull extending along a longitudinal main axis, and at least one vehicle uprighting device configured to alter a trim angle of the vehicle between a nominal horizontal position of the vehicle and a vertical position of the vehicle, characterised in that the vehicle uprighting device includes one or more arms mounted on the hull by a proximal end and rotatably hinged to the hull, and including a float at a distal free end.

An autonomous underwater vehicle, which includes a hull extending along a longitudinal main axis, and at least one vehicle uprighting device configured to alter a trim angle of the vehicle between a nominal horizontal position of the vehicle and a vertical position of the vehicle, characterised in that the vehicle uprighting device includes one or more arms mounted on the hull by a proximal end and rotatably hinged to the hull, and including a float at a distal free end.

A recovery system for an unmanned underwater vehicle (UUV) includes an elongate recovery container sized to contain the UUV, and a recovery cable coupled to the elongate recovery container, where the recovery cable is retractable into the elongate recovery container to capture and stow the UUV within the elongate recovery container. The system also includes the UUV, which includes a forward looking sonar system configured to locate the recovery cable and a capture clip coupled to a nose portion of the UUV, where the capture clip is configured to be releasably secured to the recovery cable. The UUV further includes at least one ballast tank capable of trimming the UUV to a vertical orientation.

A recovery system for an unmanned underwater vehicle (UUV) includes an elongate recovery container sized to contain the UUV, and a recovery cable coupled to the elongate recovery container, where the recovery cable is retractable into the elongate recovery container to capture and stow the UUV within the elongate recovery container. The system also includes the UUV, which includes a forward looking sonar system configured to locate the recovery cable and a capture clip coupled to a nose portion of the UUV, where the capture clip is configured to be releasably secured to the recovery cable. The UUV further includes at least one ballast tank capable of trimming the UUV to a vertical orientation.

A self-balanced pressure hull device, belonging to the field of pressure structure technology of deep-sea submersibles, being assembled by nesting, from inside to outside, a spherical inner housing, a spherical intermediate housing and a spherical outer housing around the sphere centre, pairs of symmetric coaxial connecting shaft components being connected between the spherical inner housing and the spherical intermediate housing and between the spherical intermediate housing and the spherical outer housing, respectively; axes of the two pairs of connecting shaft components are perpendicular to each other so as to enable the spherical inner housing and the spherical intermediate housing to rotate relative to each other, and the spherical intermediate housing and the spherical outer housing to rotate relative to each other; and each of the connecting shaft components in the two pairs being provided with a spring damper for resisting the axial impact between each two adjacent housings.

A mass shifting apparatus and system for inducing a vertical dive in submersible conveyances. Furthermore, an apparatus for inducing a submersible conveyance into a vertical dive, comprising a track, having a proximal end and distal end, defining a slide path wherein the track is fixed to an external surface of a submersible conveyance in alignment with a dive vector; a shifting weight operably engaged with the slide path to traverse between the proximal end and the distal end, wherein the shifting weight provides a balancing moment to the submersible conveyance when adjacent to the proximal end, and wherein driving the shifting weight towards the distal end provides dive moment to the submersible conveyance; and a means for driving the shifting weight along the slide path. In one embodiment, a modular apparatus for inducing a modular submersible conveyance into a vertical dive.

A mass shifting apparatus and system for inducing a vertical dive in submersible conveyances. Furthermore, an apparatus for inducing a submersible conveyance into a vertical dive, comprising a track, having a proximal end and distal end, defining a slide path wherein the track is fixed to an external surface of a submersible conveyance in alignment with a dive vector; a shifting weight operably engaged with the slide path to traverse between the proximal end and the distal end, wherein the shifting weight provides a balancing moment to the submersible conveyance when adjacent to the proximal end, and wherein driving the shifting weight towards the distal end provides dive moment to the submersible conveyance; and a means for driving the shifting weight along the slide path. In one embodiment, a modular apparatus for inducing a modular submersible conveyance into a vertical dive.

A water drone capable of navigating on the surface, or below the surface, of a body of water. In some embodiments such a vehicle is light-weight, electric-powered, and propeller-driven, and may be operated by remote control from the shore and guided with simple autopilot commands. The vehicle may have two actuators at the rear of the vehicle, each including a motor and a propeller, and each capable of producing forward or reverse thrust. The vehicle may be capable of travelling horizontally through the surf zone and diving vertically through the water column to the seafloor. The vehicle may monitor its own location and depth and may measure environmental conditions such as water temperature; such measurements may be communicated back to the operator using a telemetry system.