A method of controlling attitude of a marine vessel includes identifying a natural roll frequency of the marine vessel, measuring a roll motion of the marine vessel with an attitude sensor, and then determining that the roll motion exceeds the threshold roll where no corresponding steering input is present. The method further includes determining a counteracting drive movement for at least one propulsion device based on the measured roll motion and the natural roll frequency of the marine vessel. A steering actuator is then controlled to move the at least one propulsion device to effectuate the counteracting drive movement so as to counteract an environmentally-induced roll motion of the marine vessel.

A method of controlling attitude of a marine vessel includes identifying a natural roll frequency of the marine vessel, measuring a roll motion of the marine vessel with an attitude sensor, and then determining that the roll motion exceeds the threshold roll where no corresponding steering input is present. The method further includes determining a counteracting drive movement for at least one propulsion device based on the measured roll motion and the natural roll frequency of the marine vessel. A steering actuator is then controlled to move the at least one propulsion device to effectuate the counteracting drive movement so as to counteract an environmentally-induced roll motion of the marine vessel.

A peddle-actuated water propulsion device includes a seat with lower body harness, a support tube, a pair of crank-type pedals, and a propeller within a protective screen guard. The pedals are in mechanical communication with the propeller. The propeller is configured to accept a plurality of differently sized blades and may be positioned at a user-selected angle.

A system for maintaining a marine vessel in a body of water at a selected position and orientation includes a global positioning system that determines a global position and heading of the vessel and a proximity sensor that determines a relative position and bearing of the vessel with respect to an object near the vessel. A controller operable in a station keeping mode is in signal communication with the GPS and the proximity sensor. The controller chooses between using global position and heading data from the GPS and relative position and bearing data from the proximity sensor to determine if the vessel has moved from the selected position and orientation. The controller calculates thrust commands required to return the vessel to the selected position and orientation and outputs the thrust commands to a marine propulsion system, which uses the thrust commands to reposition the vessel.

A system for maintaining a marine vessel in a body of water at a selected position and orientation includes a global positioning system that determines a global position and heading of the vessel and a proximity sensor that determines a relative position and bearing of the vessel with respect to an object near the vessel. A controller operable in a station keeping mode is in signal communication with the GPS and the proximity sensor. The controller chooses between using global position and heading data from the GPS and relative position and bearing data from the proximity sensor to determine if the vessel has moved from the selected position and orientation. The controller calculates thrust commands required to return the vessel to the selected position and orientation and outputs the thrust commands to a marine propulsion system, which uses the thrust commands to reposition the vessel.

An outboard motor is provided with: an encoder which detects the rotational speed of an engine; a position sensor which detects an operating position of a shift lever; and a state quantity detection unit which detects a state quantity of a shift actuator. A control device of the outboard motor determines whether the state quantity is more than or equal to a stop-initiating threshold value when the operating position has been switched. If the state quantity is more than or equal to the stop-initiating threshold value, the control device implements a stop control to stop ignition and/or fuel injection in the engine.

The invention provides a structure of a propeller ship which can achieve improvement of fuel consumption, and enlarge an amount of cargo per ship total length. Rudders 12 are provided at laterally symmetrical positions of a ship center line in a front side of a propeller 11 and in a rear side of a buttock line.

The invention provides a structure of a propeller ship which can achieve improvement of fuel consumption, and enlarge an amount of cargo per ship total length. Rudders 12 are provided at laterally symmetrical positions of a ship center line in a front side of a propeller 11 and in a rear side of a buttock line.

The purpose is providing a ship handling device easily determining a predetermined correction coefficient regardless of positions of a side thruster and a forward/backward propeller and the center of gravity of a ship and the shape of the ship. The device is provided with a joystick lever for indicating a propulsion direction and the magnitude of thrust by tilting direction and angle, wherein: a lateral movement thrust is generated by the side thruster in accordance with the joystick lever; a first correction thrust is generated by the forward/backward propeller in accordance with the joystick lever so as to cancel out a rotation moment; and a first correction coefficient for calculating a first correction thrust with respect to the lateral movement thrust is determined.

The purpose is providing a ship handling device easily determining a predetermined correction coefficient regardless of positions of a side thruster and a forward/backward propeller and the center of gravity of a ship and the shape of the ship. The device is provided with a joystick lever for indicating a propulsion direction and the magnitude of thrust by tilting direction and angle, wherein: a lateral movement thrust is generated by the side thruster in accordance with the joystick lever; a first correction thrust is generated by the forward/backward propeller in accordance with the joystick lever so as to cancel out a rotation moment; and a first correction coefficient for calculating a first correction thrust with respect to the lateral movement thrust is determined.