An underwater watercraft including a passenger compartment and an ingress/egress port in which the watercraft has buoyancy and center of gravity adjusted to maintain a generally level or other desired attitude when submerged, and an optionally angled attitude at a water surface for ingress/egress. The attitude is also adjustable via the placement of ballast and optionally including a movable ballast that adjusts the location of the center of gravity as desired. The ingress-egress port optionally includes an entry elevated from a main passenger compartment and including a riser and optionally removable or concealable handrails. The ingress-egress port has an angled orientation in a submerged mode, and an optional orientation generally parallel to the water surface or angled but above the surface in a surface mode.

An underwater watercraft including a passenger compartment and an ingress/egress port in which the watercraft has buoyancy and center of gravity adjusted to maintain a generally level or other desired attitude when submerged, and an optionally angled attitude at a water surface for ingress/egress. The attitude is also adjustable via the placement of ballast and optionally including a movable ballast that adjusts the location of the center of gravity as desired. The ingress-egress port optionally includes an entry elevated from a main passenger compartment and including a riser and optionally removable or concealable handrails. The ingress-egress port has an angled orientation in a submerged mode, and an optional orientation generally parallel to the water surface or angled but above the surface in a surface mode.

A buoyancy system for an underwater autonomous vehicle is provided. The buoyancy system includes one or more pressure vessels, a primary pump connected to each of the one or more pressure vessels with the primary pump configured to pump liquid from the one or more pressure vessels. The buoyancy system further includes a controller communicatively coupled to the primary pump and configured to operate the main pump, and a power source configured to provide power to the controller and the primary pump. Each pressure vessel includes a cylindrical shell with an inner surface, spaced apart axial support members disposed on the inner surface of the cylindrical shell, and radial support plates between the axial support members.

A buoyancy system for an underwater autonomous vehicle is provided. The buoyancy system includes one or more pressure vessels, a primary pump connected to each of the one or more pressure vessels with the primary pump configured to pump liquid from the one or more pressure vessels. The buoyancy system further includes a controller communicatively coupled to the primary pump and configured to operate the main pump, and a power source configured to provide power to the controller and the primary pump. Each pressure vessel includes a cylindrical shell with an inner surface, spaced apart axial support members disposed on the inner surface of the cylindrical shell, and radial support plates between the axial support members.

A pump-less buoyancy engine for an autonomous underwater vehicle (AUV) includes a buoyancy reduction structure without a hydraulic pump for reducing the buoyancy of the AUV to cause the AUV to descend in the water; and a weight dropping structure for dropping prepackaged weights out of the AUV to cause the AUV to ascend in the water, where the AUV moves forward when descending and ascending.

A driving method is implemented to a lifting device of an underwater survey system, and the lifting device includes a phase-change heat exchange module, an oil bag module, a pressurized energy storage module, and a drive energy storage module. The driving method includes: controlling the pressurized energy storage module to extract hydraulic oil in the oil bag module to descend the lifting device; during a transformation of a phase-change material, the pressurized energy storage module transmitting hydraulic oil to the phase-change heat exchange module; transmitting the hydraulic oil inside the oil bag module to the pressurized energy storage module to descend the lifting device; controlling the drive energy storage module to transmit hydraulic oil to the oil bag module for rising the lifting device; and during a transformation of the phase-change material, transmitting the hydraulic oil in the phase-change heat exchange module to the drive energy storage module.

An unmanned sailing vehicle comprising: a primary hull; a rigid wing rotationally coupled with said primary hull that freely rotates about a rotational axis of said rigid wing; a boom comprising a first end extending from a leading edge of said rigid wing and a second end extending from a trailing edge of said rigid wing, said first end of said boom comprising a counterweight configured to dynamically balance a wing system comprising said rigid wing, said boom, and said tail with respect to said rotational axis of said rigid wing; a tail coupled to said second end of said boom; a control surface element disposed on said tail and configured to aerodynamically control a wing angle of said rigid wing based on a position of said control surface element; and a controller configured to determine a control surface angle and generate a signal to position said control surface element.

An unmanned sailing vehicle comprising: a primary hull; a rigid wing rotationally coupled with said primary hull that freely rotates about a rotational axis of said rigid wing; a boom comprising a first end extending from a leading edge of said rigid wing and a second end extending from a trailing edge of said rigid wing, said first end of said boom comprising a counterweight configured to dynamically balance a wing system comprising said rigid wing, said boom, and said tail with respect to said rotational axis of said rigid wing; a tail coupled to said second end of said boom; a control surface element disposed on said tail and configured to aerodynamically control a wing angle of said rigid wing based on a position of said control surface element; and a controller configured to determine a control surface angle and generate a signal to position said control surface element.

A submersible node and a method and system for using the node to acquire data, including seismic data is disclosed. The node incorporates a buoyancy system to provide propulsion for the node between respective landed locations by varying the buoyancy between positive and negative. A first acoustic positioning system is used to facilitate positioning of a node when landing and a second acoustic positioning system is used to facilitate a node transiting between respective target landed locations.

A submersible node and a method and system for using the node to acquire data, including seismic data is disclosed. The node incorporates a buoyancy system to provide propulsion for the node between respective landed locations by varying the buoyancy between positive and negative. A first acoustic positioning system is used to facilitate positioning of a node when landing and a second acoustic positioning system is used to facilitate a node transiting between respective target landed locations.