A method of de-spinning a rotor of a propulsion system includes providing one or more spinning rotors rotatably mounted on a frame with a bearing having a bearing outer race, bearing balls, and bearing inner race; providing a force mechanism coupled with the one or more spinning rotors for applying a load to the one or more spinning rotors; and loading an outer portion of the outer bearing race, bearing ball, and inner bearing race of the bearing, a load on the outer portion of the bearing race, bearing ball, and inner bearing race of the bearing corresponding to a force applied to the one or more spinning rotors by the drive mechanism. The one or more spinning rotors de-spin at a rate corresponding to the load on the bearing balls.

A system for servicing watercraft includes one or more waterborne platforms. Each waterborne platform includes an electric power supply, a driving system for moving the waterborne platform in a body of water, a watercraft interfacing system configured to at least supply electric power to an electrically-powered watercraft, and a control interface configured to exchange data with a controller. The controller is configured to: receive input data, determine respective destination locations for the waterborne platforms to supply electric power to the electrically-powered watercraft, and send control data that includes data indicating the destination locations to the waterborne platforms.

A system and a method produce electrical power for ship propulsion. Power and fuel modules are configured for modular use during travel. The power and fuel modules may be standard freight size containers so that the amount of fuel and power for a trip may be adjusted based on the needs of the trip. A control system may be automated to control loading and unloading of fuel or power modules into the power distribution system, connection or disconnection of fuel or power modules, and adjust distribution of power to the ship's electrical grid based on consumption demands.

A propulsion system for a marine vessel in a body of water includes an water intake formed in the hull, a impeller disc rotatable about a vertical axis for raising water and increasing the momentum of water in a plenum chamber, and a plurality of control gates located around the periphery of the hull. The impeller disc has a large outer diameter and is formed to enable efficient rotation by an electric motor. One or more of the water intake, the plenum chamber, the impeller disc and the control gates is designed to reduce acoustic noise generated by the marine vessel, direct the acoustic noise to avoid broadband acoustic noise, increase efficiency of the propulsion system and provide additional safety to passengers on the marine vessel and marine life in the body of water.

A propulsion system for a marine vessel in a body of water includes an water intake formed in the hull, a impeller disc rotatable about a vertical axis for raising water and increasing the momentum of water in a plenum chamber, and a plurality of control gates located around the periphery of the hull. The impeller disc has a large outer diameter and is formed to enable efficient rotation by an electric motor. One or more of the water intake, the plenum chamber, the impeller disc and the control gates is designed to reduce acoustic noise generated by the marine vessel, direct the acoustic noise to avoid broadband acoustic noise, increase efficiency of the propulsion system and provide additional safety to passengers on the marine vessel and marine life in the body of water.

The invention relates to a drive (10) for a boat as an additional drive or alternative drive to a main drive (20), which is provided with a cavitation plate (24). The drive (10) in this case comprises an electric motor (8) and is designed in such a manner that it can easily be fastened to the main drive. The drive (10) is configured to be fastened to the cavitation plate such that after assembly it does not project rearwards beyond the cavitation plate (24) of the main drive (20).

The invention relates to a drive (10) for a boat as an additional drive or alternative drive to a main drive (20), which is provided with a cavitation plate (24). The drive (10) in this case comprises an electric motor (8) and is designed in such a manner that it can easily be fastened to the main drive. The drive (10) is configured to be fastened to the cavitation plate such that after assembly it does not project rearwards beyond the cavitation plate (24) of the main drive (20).

A system for propelling a magnetic robotic device through a human comprises a magnetic actuator device operable to generate a rotating magnetic field, and a magnetic robotic device comprising a compliant body and at least two permanent magnets supported by and spatially separated about the compliant body. A non-magnetic region can also be oriented between the at least two permanent magnets. The at least two permanent magnets can be alternating or non-alternating in polarity with each other. In response to application of the rotating magnetic field generated by the magnetic actuator device and that is situated proximate the magnetic robotic device, the rotating magnetic field effectuates undulatory locomotion of the magnetic robotic device to propel the magnetic robotic device through a human, such as through a natural lumen. Further, the magnetic robotic device can optionally be supported by a catheter or endoscope to assist with propelling a distal end through a human.

A system for propelling a magnetic robotic device through a human comprises a magnetic actuator device operable to generate a rotating magnetic field, and a magnetic robotic device comprising a compliant body and at least two permanent magnets supported by and spatially separated about the compliant body. A non-magnetic region can also be oriented between the at least two permanent magnets. The at least two permanent magnets can be alternating or non-alternating in polarity with each other. In response to application of the rotating magnetic field generated by the magnetic actuator device and that is situated proximate the magnetic robotic device, the rotating magnetic field effectuates undulatory locomotion of the magnetic robotic device to propel the magnetic robotic device through a human, such as through a natural lumen. Further, the magnetic robotic device can optionally be supported by a catheter or endoscope to assist with propelling a distal end through a human.

A power supply system for a floating mobile body or an underwater mobile body moving on or under water in a water channel or a water tank is configured to supply, in a non-contact manner, power from a power transmission apparatus to a power reception apparatus. The power transmission apparatus includes an AC power source that includes a first terminal and a second terminal and outputs an AC power wave, a power transmission inductance element having one terminal connected to the first terminal, and a first power transmission electrode provided in the water channel or the water tank and having an end portion connected to another terminal of the power transmission inductance element. The power reception apparatus includes a first power reception electrode, a second power reception electrode provided apart from the first power reception electrode, and a power reception inductance element connected to the first power reception electrode.