An underwater robotic device includes a housing unit, a control unit and a propelling unit. The housing unit includes a base seat and an upper cover in liquid-tight engagement with the base seat. The control unit is disposed within the housing unit and includes a circuit module and a center-of-gravity transferring module which is electronically connected with the circuit module. The center-of-gravity transferring module has a movable weight member and a transfer driving mechanism which drives movement of the weight member so as to vary a position of a center of gravity of the underwater robotic device and to control downward and upward moving directions of the underwater robotic device in the water. The propelling unit is connected with the housing unit and is electronically connected with the control unit to produce a propelling force to move the underwater robotic device forward in the water.

An example towable device for a watercraft is provided. The device includes an adaptive mount configured to receive a transducer assembly and a connection feature for attachment of a linking mechanism for attachment of the towable device to the watercraft. The device and the transducer assembly are configured to glide through an underwater environment at a first depth that is different from a second depth of a hull of the watercraft via the linking mechanism. An example method for creating an overlay for a map or chart is also provided. The method includes receiving sonar data, forming the overlay using the sonar data, and causing presentation of the overlay over the map or chart on a display of a marine electronic device.

An example towable device for a watercraft is provided. The device includes an adaptive mount configured to receive a transducer assembly and a connection feature for attachment of a linking mechanism for attachment of the towable device to the watercraft. The device and the transducer assembly are configured to glide through an underwater environment at a first depth that is different from a second depth of a hull of the watercraft via the linking mechanism. An example method for creating an overlay for a map or chart is also provided. The method includes receiving sonar data, forming the overlay using the sonar data, and causing presentation of the overlay over the map or chart on a display of a marine electronic device.

A system and method for deploying and retrieving a plurality of ocean bottom seismic nodes to and from the seabed by using a floating platform. The system comprises an autonomous underwater vehicle (AUV) coupled to a node skid that is configured to handle a plurality of ocean bottom seismic nodes. The AUV and coupled skid may be lowered to and raised from the seabed and a platform in a garage. The AUV may comprise one or more fuel cells in addition to or as a replacement of traditional rechargeable batteries. The system may utilize an unmanned underwater vehicle (UUV) or unmanned surface vehicle (USV) to monitor and track AUV deployment and to provide acoustic communications between the surface platform and the AUV.

A system and method for deploying and retrieving a plurality of ocean bottom seismic nodes to and from the seabed by using a floating platform. The system comprises an autonomous underwater vehicle (AUV) coupled to a node skid that is configured to handle a plurality of ocean bottom seismic nodes. The AUV and coupled skid may be lowered to and raised from the seabed and a platform in a garage. The AUV may comprise one or more fuel cells in addition to or as a replacement of traditional rechargeable batteries. The system may utilize an unmanned underwater vehicle (UUV) or unmanned surface vehicle (USV) to monitor and track AUV deployment and to provide acoustic communications between the surface platform and the AUV.

A system for generating electricity from an underwater stream for generating electricity for the electric grid or for producing hydrogen includes an underwater turbine. The underwater turbine includes an upper pontoon, a lower pontoon, and a pylon structure that extends between and interconnects the upper pontoon and the lower pontoon. The underwater turbine also includes a single propeller assembly rotatably coupled to the lower pontoon. Rotation of the propeller operates a generator to generate electricity. The underwater turbine can be moored to a sea floor via a mooring weight. An optional friction winch is operable to raise or lower the underwater turbine relative to the sea floor.

A system for generating electricity from an underwater stream for generating electricity for the electric grid or for producing hydrogen includes an underwater turbine. The underwater turbine includes an upper pontoon, a lower pontoon, and a pylon structure that extends between and interconnects the upper pontoon and the lower pontoon. The underwater turbine also includes a single propeller assembly rotatably coupled to the lower pontoon. Rotation of the propeller operates a generator to generate electricity. The underwater turbine can be moored to a sea floor via a mooring weight. An optional friction winch is operable to raise or lower the underwater turbine relative to the sea floor.

A ballast control system is used which fits small submersible vehicles. The system is used to vary the vehicle ballast in comparison to the surrounding water without the need for the propulsion system to regulate the depth. A piezoelectric fluid pump controls the ballast system and can reach depths to 1,000 ft. The pump moves fluid between an internal reservoir and an external bladder in a very small package and weight. The ballast control system uses typical underwater battery voltages. The pumping system does not need auxiliary devices. The system can be configured to trim the attitude of the vehicle along its longitudinal and/or lateral axes. The invention provides these capabilities with minimal drain on the vehicle's battery system and impact on the vehicle's payload capacity. An emergency system ensures that the submersible vehicle returns to the surface when power is lost.

A ballast control system is used which fits small submersible vehicles. The system is used to vary the vehicle ballast in comparison to the surrounding water without the need for the propulsion system to regulate the depth. A piezoelectric fluid pump controls the ballast system and can reach depths to 1,000 ft. The pump moves fluid between an internal reservoir and an external bladder in a very small package and weight. The ballast control system uses typical underwater battery voltages. The pumping system does not need auxiliary devices. The system can be configured to trim the attitude of the vehicle along its longitudinal and/or lateral axes. The invention provides these capabilities with minimal drain on the vehicle's battery system and impact on the vehicle's payload capacity. An emergency system ensures that the submersible vehicle returns to the surface when power is lost.

The present disclosure provides a cleaning device, including a cleaning device body, a drive mechanism, a filtering mechanism, a liquid inlet portion, a liquid outlet portion, and a mode switching member. The drive mechanism is configured to generate a suction force to form a first water flow path with the liquid inlet portion, the filtering mechanism, and the liquid outlet portion. The mode switching member is configured to allow the cleaning device to be switched between a first motion state and a third motion state. Switching of the cleaning device between the first motion state and the third motion state includes switching of a second motion state. The cleaning device performs underwater cleaning in the first motion state, cleans a pool wall or a waterline in the second motion state, and performs water surface cleaning in the third motion state.