A ship handling device enabling easy turning calibration. With a ship handling device (7), during turning calibration with the ship handling device (7), the joystick lever (10) is turned to rotate the forward-backward propellers (4) on the port and starboard sides of the ship, and the joystick lever (10) is tilted to change a forward-thrust/backward-thrust ratio of the forward-backward propeller (4) on the port or starboard side or to change the rotation speeds. When a calibration execution switch (10a) is operated, thrusts generated with the changed forward-thrust backward-thrust ratio are set as correction coefficients, or, among thrusts generated at the changed rotation speeds (Npn, Nsn) of the forward-backward propellers (4) on the port and starboard sides, thrusts generated by the forward-backward propellers (4) on the port and starboard sides according to the tilting of the joystick lever (10) are set as correction coefficients (Cp, Cs).

A ship handling device enabling easy turning calibration. With a ship handling device (7), during turning calibration with the ship handling device (7), the joystick lever (10) is turned to rotate the forward-backward propellers (4) on the port and starboard sides of the ship, and the joystick lever (10) is tilted to change a forward-thrust/backward-thrust ratio of the forward-backward propeller (4) on the port or starboard side or to change the rotation speeds. When a calibration execution switch (10a) is operated, thrusts generated with the changed forward-thrust backward-thrust ratio are set as correction coefficients, or, among thrusts generated at the changed rotation speeds (Npn, Nsn) of the forward-backward propellers (4) on the port and starboard sides, thrusts generated by the forward-backward propellers (4) on the port and starboard sides according to the tilting of the joystick lever (10) are set as correction coefficients (Cp, Cs).

A marine propulsion system includes a water intake guide block with a flow guide passage, a propulsion device including a housing connected to the water intake guide block and a propeller mounted in the housing, a fixed nozzle connected to the housing of the propulsion device, a swinging nozzle connected to the fixed nozzle and biasable leftward and rightward relative to the fixed nozzle, and a contra type bossing pivotally connected to the fixed nozzle and biasable up and down relative to the fixed nozzle. When rotating the propeller, water is sucked into the flow guide passage and propelled by the propeller to eject backward through the fixed nozzle, and the swinging nozzle is biased leftward/rightward to control leftward/rightward turning of the boat, and the contra type bossing is biased upward/downward to control the pitch angle of the boat and forward/backward movement of the boat.

A grid (100) is for a tunnel thruster (200). The grid (100) includes a plurality of first radially extending bars (101) arranged at angular intervals from each other, and a plurality of first connecting bars (102). Each of the first connecting bars (102) are connected between adjacent first radially extending bars (101).

A marine propulsion system having a steering axis that allows pivoting of propellers along a first vertical axis directly beneath a gear box located inside the hull of a boat. A lower gear box can be placed within a vented or non-vented tunnel eliminating the need for a rudder and providing directional control of the boat by the orientation of the lower gear box. Surface piercing propellers and/or counter-rotating propellers may be used with the propellers pivoted around the vertical axis of the gear box. The offset steering axis allows pivoting around the first vertical axis wherein a secondary axis is moved with minimal drag providing superior maneuverability at both high and low speeds.

A device (100) has surfaces (21, 22, 23, 24) and an anti-biofouling system (10) comprising at least one light source (11, 12) for performing an anti-biofouling action on at least a majority of the surfaces, the at least one light source (11, 12) being adapted to emit rays of anti-biofouling light. The surfaces (21, 22, 23, 24) are configured relative to each other and to the at least one light source (11, 12) such that during operation of the at least one light source, at least a majority of the surfaces (21, 22, 23, 24) is free from shadow with respect to the rays of anti-biofouling light from the at least one light source (11, 12), wherein it may be possible for the rays of anti-biofouling light to reach the surfaces (21, 22, 23, 24) by skimming along the surfaces (21, 22, 23, 24).

A device (100) has surfaces (21, 22, 23, 24) and an anti-biofouling system (10) comprising at least one light source (11, 12) for performing an anti-biofouling action on at least a majority of the surfaces, the at least one light source (11, 12) being adapted to emit rays of anti-biofouling light. The surfaces (21, 22, 23, 24) are configured relative to each other and to the at least one light source (11, 12) such that during operation of the at least one light source, at least a majority of the surfaces (21, 22, 23, 24) is free from shadow with respect to the rays of anti-biofouling light from the at least one light source (11, 12), wherein it may be possible for the rays of anti-biofouling light to reach the surfaces (21, 22, 23, 24) by skimming along the surfaces (21, 22, 23, 24).

Described herein are paddlecraft such as kayaks modified to include a motor to assist the paddling action of a user of the paddlecraft. The paddlecraft has a motor driven propeller located in an elongated channel within a paddlecraft base which drives water flow from an inlet side to an outlet side of the motor driven propeller via the elongated channel to drive movement of the paddlecraft. At least one movement sensor may be located on the paddlecraft and motor driven propeller actuation is driven by a user when the at least one movement sensor senses paddling movement by the user. A network comprising multiple paddlecraft and movement sensor communication is also described along with a method of assisting a paddlecraft user to generate motion.

Described herein are paddlecraft such as kayaks modified to include a motor to assist the paddling action of a user of the paddlecraft. The paddlecraft has a motor driven propeller located in an elongated channel within a paddlecraft base which drives water flow from an inlet side to an outlet side of the motor driven propeller via the elongated channel to drive movement of the paddlecraft. At least one movement sensor may be located on the paddlecraft and motor driven propeller actuation is driven by a user when the at least one movement sensor senses paddling movement by the user. A network comprising multiple paddlecraft and movement sensor communication is also described along with a method of assisting a paddlecraft user to generate motion.

A boat propulsor includes a duct, a propeller in the duct and rotatable around a rotation axis extending along an axial direction of the duct, and a rotator to rotate the propeller. An upper portion of the duct includes a plate extending from the duct in the axial direction and including holes. Water streams passing around and along the duct are attenuated as the water streams pass through the holes in the plate.