Described is a robot (1) for cleaning swimming pools comprising a main body (2), a plurality of rotors (3), a control unit and means for cleaning the swimming pool.

The main body (2) has at least one sealed containment space (4).

The plurality of rotors (3) is configured for generating a hydrodynamic thrust designed for moving the robot inside an entire space of the swimming pool.

The control unit inserted in the containment space (4) and is configured for modifying at least one respective operating parameter of each rotor (3) in such a way as to direct the hydrodynamic thrust.

A method of operating a thruster apparatus involves causing a first propeller to rotate in response to pressure of a first flow of pressurized hydraulic fluid, and causing a second propeller to rotate in response to pressure of a second flow of pressurized hydraulic fluid separate from the first flow of pressurized hydraulic fluid. Thruster apparatuses are also disclosed.

A cover device for at least partially closing an underwater opening in a hull of a watercraft includes a variable-volume hollow-chamber lip assembly including at least two hollow-chamber lips and one buoyancy body. The at least one hollow-chamber lip is volume-variable by supplying a fluid to or removing a fluid from an interior thereof, and the at least one hollow-chamber lip assembly is shiftable between an expanded state and a contracted state by supplying or removing the fluid.

A well intervention monohull vessel and method of use including a tower type open derrick structure disposed on a deck of the vessel and a sole point land out having a sole point of riser tension contact with a top of the derrick structure. The vessel may also include subsea equipment such as an intervention riser system and an emergency disconnect package, a moon pool door preferably capable of transporting the subsea equipment, an intervention lift frame, a surface coiled tubing reel, a riser storage area, a rail, a pallet, a subsea tree, a crane, and/or drawworks.

The present invention provides a remote-controllable underwater device for manoeuvring a vessel. The device comprising at least one housing, a connection unit provided on the housing for rigidly attaching below the water to the vessel to be manoeuvred, at least one propeller mounted on the housing for moving the device and the vessel attached to the connection unit, an antenna for communication with the device from a remote control unit, at least one sensor for path tracking and positioning of the device and the vessel, and a power source for providing power to the connection unit, the propeller, the antenna, and the sensor.

A marine propulsion system includes an engine-powered propulsion device coupled in torque-transmitting relationship with an engine. A non-engine-powered propulsion device is coupled to a source of electric or hydraulic power. A control module is provided in signal communication with the engine-powered propulsion device and the non-engine-powered propulsion device. A user-operated input device is in signal communication with the control module. The marine propulsion system operates in a non-engine-powered propulsion mode in response to the control module determining the following: the engine was previously running; a speed of the engine is below an engine-stopped speed threshold; the marine propulsion system is on; and a request for movement of the vessel has been input via the user-operated input device. While the marine propulsion system operates in the non-engine-powered propulsion mode, the control module controls the non-engine-powered propulsion device to generate thrust to maneuver the vessel according to the request for movement.

A ship including an engine, a jet propulsion device, a ship controller, and a ship position detection unit, in which the jet propulsion device includes a nozzle that ejects a jet stream generated by the driving force output from the engine, and a bucket that changes a direction of the jet stream, the position of the bucket includes at least a forward-side intermediate position between the forward position and the neutral position, the ship controller has a ship fixed point holding mode in which feedback control of the engine and the jet propulsion device is performed based on a deviation between a preset target ship position and the actual ship position, and both control of the position of the bucket including the forward-side intermediate position and control of a rotational speed of the engine are performed in the ship fixed point holding mode.

The invention provides a device which can reduce the drag and assist the steering of the ship, mainly to set up a 3-way pipe in the bow where is below the water level. The 3-way pipe leads to three openings at the stem, the port side and the starboard side respectively. At least one control valve (or deflector) can be provided in the 3-way piping system. The valve (or deflector) can be controlled from the bridge, with a diversion device. When the ship sails forward, water flows into the 3-way pipe from the forward pipe, distributed to both side pipes and then outflow, so that it can reduce the pressure drag to the stem, improve the ship's speed and save bunker. When the valve (or deflector) is set as neutral, the water will be distributed evenly to both side pipes, which will not affect the ship's heading. When the valve (or deflector) deflects more water to either side's pipe, the ship will turn to the opposite side.

A vessel with auxiliary steering includes a vessel hull with a bow/stern centerline and a port and starboard side. The vessel has (i) a main propulsion unit including at least one propeller and at least one main rudder, and (ii) a secondary propulsion unit including at least one directional water jet thruster on each of the port and starboard side of the vessel hull. The water jet thrusters are configured to direct water outwardly and perpendicularly to the centerline of the hull, and a control system coordinates the direction of the main rudder and the flow direction of at least one water jet thruster.

A lifting spindle arrangement is disclosed for a retractable thruster unit of a marine vessel, the lifting spindle having a lower end and an upper end and being supported at its lower end to a lower support structure by a lower support assembly and at its upper end to an upper support structure by an upper support assembly. The lifting spindle is provided at its both ends with a locking member for such a connection to the support structures such that each end of the lifting spindle may freely move in an axial direction away from the opposite end of the lifting spindle.