The present invention relates to an underwater drone which is an unmanned mobile which can move in the water, and more particularly to a communication system for the underwater drone which performs communication between the underwater drone and a land-based controller (or maneuvering device). The present invention also relates to an airlock apparatus for the drone which transfers the drone into or from facilities or containers, or equipment sealed (or closed) against surrounding environment. The communication system for an underwater drone includes an underwater drone (1) configured to move in the water, at least one transmitting and receiving antenna (2) provided in an area where the transmitting and receiving antenna (2) can communicate with the underwater drone (1) by wireless communication, and a controller or a maneuvering device (5) connected to the at least one transmitting and receiving antenna (2) by a wired cable (4) and configured to control the underwater drone (1).

Multiple autonomous underwater vehicles (AUVs) are operated by a host platform by configuring the AUVs with intermediate nodes (such as unmanned surface vehicles (USVs)) so as to allow the host platform to manage multiple AUVs. The intermediate nodes act as a relay for communications between the host platform and the AUVs allowing the host platform to scale to higher numbers of vehicles thus simultaneously operating the entire fleet of AUVs. The AUVs may provide underwater mapping data. The host platform may be stationary. The host platform may communicate with the intermediate nodes by satellite.

Multiple autonomous underwater vehicles (AUVs) are operated by a single host surface vehicle (HSV) by configuring the AUVs with intermediate nodes (such as unmanned surface vehicles (USVs)) so as to allow the HSV to manage multiple AUVs. The intermediate nodes act as a relay for communications between the HSV and the AUVs allowing the HSV to scale to higher numbers of vehicles thus simultaneously operating the entire fleet of AUVs. The AUVs may provide underwater mapping data.

Embodiments of the present invention provide a navigation system which, on the one hand, is arranged on sides of the underwater vehicle/AUV and, on the other hand, includes a surface transmitter as a counterpart. The two units communicate with each other such that the surface transmitter emits its signal directed to the position of the underwater vehicle and/or that the surface transmitter follows the underwater vehicle to improve the position determination capability.

An underwater positioning system provides position information for a rover, moveable within a reference frame. The system may comprise: at least one beacon having a light source, located at a fixed position within the reference frame; an underwater imaging device, moveable with the rover in the reference frame to observe the light source from different viewpoints and determine direction data representing a direction or change in direction of the light source with respect to the imaging device; an orientation sensor, associated with the imaging device to determine an orientation of the imaging device with respect to the reference frame and generate orientation data; and a scaling element for providing scaling data representative of a distance between the imaging device and the light source. Various different beacons may be provided.

In alternative system implementations, the locations of light source(s) and underwater imaging device are reversed between rover and beacon(s).

Underwater navigational systems and methods utilizing sunlight polarized via scattering through the water column that does not require an underwater vehicle to surface or use a global position system to maintain precise navigational positions and headings. These navigational systems and methods may be employed by manned or unmanned underwater vehicles and may be utilized by individual units and by units operating in a swarm.

The invention relates to a field off artificial intelligence (AI) technologies, and discloses a method and an apparatus for high-order iterative self-learning control for a robotic fish, and a storage medium; the control method performs preferential iterative calculation on control gain elements in the control gain set to obtain a target control gain set; and performs high-order iterative calculation according to the target control gains, the first control input thrust and the first tracking error to obtain a target control input thrust, and then controls a robotic fish to swing according to the target control input thrust to obtain an expected speed. In this way, complete tracking and rapid convergence of a swim speed of a robotic fish in the whole operation space may be achieved.

An underwater communications network may include spaced apart nodes on a bottom of a body of water. The underwater communications network may also include fiber optic cabling connecting the spaced apart nodes. Each node may include a frame, a node short-range navigation device carried by the frame, and an unmanned underwater vehicle (UUV) carried by the frame after delivering a fiber optic cable along a navigation path from an adjacent node. The UUV may be configured to cooperate with the node short-range navigation device during an end portion of the navigation path adjacent the frame.

A passive ballast device, system and method of using same, configured for use with a submersible vehicle in a liquid environment, including a chamber having at least one rigid wall to define at least a portion of a chamber volume, and a passively movable compensator having at least first and second surfaces, the first surface configured to be exposed to the liquid environment, the second surface excluded from the liquid environment, and forming, together with the at least one wall of the chamber, a fluid-tight seal to establish the remainder of the chamber volume, to exclude the liquid environment from the chamber volume and configured to adjust the chamber volume to at least a first chamber volume and a second chamber volume. The chamber volume is configured to establish at least a first buoyancy and second buoyancy, the compensator is configured to respond to a change in environmental pressure within the liquid environment, and the compensator is passively moved by the change in environmental pressure to change the first chamber volume to the second chamber volume, thereby changing from the first buoyancy to the second buoyancy.

A method and apparatus for positioning a mobile robot inside a vertical cylindrical Aboveground Storage Tank filled with a liquid is described. No additional hardware is needed other than the robot itself. The only piece of information needed is the tank's diameter which is known by construction. The robot carries proprioceptive sensors needed to propagate its position estimate as well as exteroceptive sensors needed to control the dead reckoning positional drift. Proprioceptive and exteroceptive data are merged using data fusion algorithms adapted to the sensor suite integrated in the vehicle, which can take different forms.