The present invention discloses a marine fishtail rudder, including a rudder blade, a first tail plate and a second tail plate. The rudder blade includes a first rudder surface and a second rudder surface. The first tail plate is hinged on the first rudder surface. The second tail plate is hinged on the second rudder surface. An electric motor is provided in the rudder blade. The electric motor is used to drive the first tail plate and the second tail plate to rotate, so that a trailing edge of the first tail plate and a trailing edge of the second tail plate are close to or away from a trailing edge of the rudder blade. The present invention discloses a marine fishtail rudder, wherein tail plates are respectively arranged on the two rudder surfaces of a rudder tail portion, and the tail plates are rotated by an electric motor. When steering, the tail plates are unfolded to form a rudder shape of a fishtail rudder to obtain a higher rudder effect. When sailing straight or reversing, the tail plates are closed to form a rudder shape of a streamlined rudder and reduce the resistance of the rudder.

The present invention discloses a marine fishtail rudder, including a rudder blade, a first tail plate and a second tail plate. The rudder blade includes a first rudder surface and a second rudder surface. The first tail plate is hinged on the first rudder surface. The second tail plate is hinged on the second rudder surface. An electric motor is provided in the rudder blade. The electric motor is used to drive the first tail plate and the second tail plate to rotate, so that a trailing edge of the first tail plate and a trailing edge of the second tail plate are close to or away from a trailing edge of the rudder blade. The present invention discloses a marine fishtail rudder, wherein tail plates are respectively arranged on the two rudder surfaces of a rudder tail portion, and the tail plates are rotated by an electric motor. When steering, the tail plates are unfolded to form a rudder shape of a fishtail rudder to obtain a higher rudder effect. When sailing straight or reversing, the tail plates are closed to form a rudder shape of a streamlined rudder and reduce the resistance of the rudder.

A ship propulsion device includes three or more propulsion units, a malfunction detection unit, and a control unit. The control unit is configured to control the three or more propulsion units. The three or more propulsion units are disposed with left-right symmetry. Based on a malfunction detected in any one of the three or more propulsion units by the malfunction detection unit while the three or more propulsion units are operating, the control unit is configured to stop the propulsion unit in which the malfunction is detected, and, on a left side and a right side of a hull, stop at least one propulsion unit of the three or more propulsion units disposed on the side opposite from the side on which the propulsion unit in which the malfunction is detected is disposed.

An arrangement including a gearwheel connected to the propulsion unit, a steering electric motor operatively connected to the gearwheel and controlled by a drive, a force transmission arrangement including a clutch between the gearwheel and the steering electric motor, and a measurement unit for measuring rotational motion positioned at each side of the clutch. The steering electric motor is arranged to rotate the gearwheel and thereby also the propulsion unit. A difference in the output signals of the two measuring units indicating slipping of the clutch is detected. The steering electric motor is controlled to at least reduce the difference in the output signals when the difference exceeds a predetermined threshold.

An arrangement including a gearwheel connected to the propulsion unit, a steering electric motor operatively connected to the gearwheel and controlled by a drive, a force transmission arrangement including a clutch between the gearwheel and the steering electric motor, and a measurement unit for measuring rotational motion positioned at each side of the clutch. The steering electric motor is arranged to rotate the gearwheel and thereby also the propulsion unit. A difference in the output signals of the two measuring units indicating slipping of the clutch is detected. The steering electric motor is controlled to at least reduce the difference in the output signals when the difference exceeds a predetermined threshold.

A steering system for a marine craft includes a steering input shaft. The steering system also includes an electric power steering (EPS) system operatively coupled to the steering input shaft, the EPS system having an electric motor that drives rotation of a system output shaft. The steering system further includes a hydraulic pump operatively coupled to the system output shaft with a gear set, the hydraulic pump having a longitudinal direction that is perpendicular to a steering input shaft axis. The steering system yet further includes a fluid reservoir located remotely relative to the hydraulic pump.

A steering system for a marine craft includes a steering input shaft. The steering system also includes an electric power steering (EPS) system operatively coupled to the steering input shaft, the EPS system having an electric motor that drives rotation of a system output shaft. The steering system further includes a hydraulic pump operatively coupled to the system output shaft with a gear set, the hydraulic pump having a longitudinal direction that is perpendicular to a steering input shaft axis. The steering system yet further includes a fluid reservoir located remotely relative to the hydraulic pump.

A device and a method for controlling an electrical steering system in a marine vessel comprising at least one steerable propulsion unit, the electrical steering system comprising a main steering system (220; 220.1) that comprises a main electric motor (221; 221.1) and a main power source, e.g. a main battery (229; 229.1); a main steering angle sensor (226; 226.1) arranged to detect the steering angle of the propulsion unit; a main control unit (240; 240.1) arranged to steer the propulsion unit and to monitor the main steering system status; an auxiliary steering system comprising an auxiliary electric motor (231; 231.1) and an auxiliary battery (239; 239.1); and an auxiliary clutch (232; 232.1) arranged to connect a drive shaft of the auxiliary electric motor to the input shaft of the steering transmission (223; 223.1). The method involves the steps of engaging the auxiliary clutch at start-up of the propulsion unit; performing a diagnostic test of the main steering system during start-up; performing a calibration of an auxiliary steering angle sensor; and disengaging the auxiliary clutch upon completion of the diagnostic test.

A maneuvering system for a ship provided with, in the stern, a port-side propulsion system, and a starboard-side propulsion system. For controlling the system, a forward or backward force of the ship 1 is obtained by the difference between the forward and backward propulsion forces of the propulsion systems and a first turning moment in a turning direction of the ship generated by the propulsion forces is offset by a second turning moment in the turning direction of the ship generated by steering a port-side rudder, whereby the ship moves in a transversal manner toward its starboard side while rotation of the ship is avoided. A high degree of maneuverability is thereby achieved with a relatively simple maneuvering operation.

A method of controlling a steering system on a marine vessel includes, in response to receiving a user input to engage a quick steer mode, employing a reduced steering ratio to translate positions of a steering wheel to desired steering angles of a marine drive. A vessel speed of a marine vessel is determined and then compared to a threshold vessel speed. An output limit is determined to prevent the marine vessel from further exceeding the threshold vessel speed while the quick steer mode is engaged. The marine drive is automatically controlled based on the output limit and a steering actuator associated with the marine drive is controlled based on the reduced steering ratio.