A redundant steering system for watercraft that transfers rudder control to an electronic steering system when a hydraulic steering system either fails or is under repair. The electronic steering system utilizes either a fueled generator or a battery or series of batteries to power electric steering and flanking motors that serve control the angular position of the rudders.

An automatic steering device may include a route calculator, an indirect target point calculating module, a command steering angle calculating module, and a steering controlling module. The route calculator may calculate a route of a ship based on positions of a plurality of target points. The indirect target point calculating module may calculate an indirect target point ahead of the ship. The command steering angle calculating module may calculate a command steering angle based on a positional relation between the route and the indirect target point. The steering controlling module may control a steering mechanism of the ship based on the command steering angle.

An automatic steering device may include a route calculator, an indirect target point calculating module, a command steering angle calculating module, and a steering controlling module. The route calculator may calculate a route of a ship based on positions of a plurality of target points. The indirect target point calculating module may calculate an indirect target point ahead of the ship. The command steering angle calculating module may calculate a command steering angle based on a positional relation between the route and the indirect target point. The steering controlling module may control a steering mechanism of the ship based on the command steering angle.

An embodiment of a system for controlling a marine vessel includes a torque and/or position sensor configured to measure at least one of a torque applied by a steering wheel of the marine vessel and a rotational position of the steering wheel, and a processing device configured to receive a measurement of the steering wheel and electronically control a steering mechanism at a stern region of the marine vessel. The processing device is configured to estimate an angle of the steering wheel, determine a corresponding angle to be applied to the steering mechanism, and transmit a steering command based on the corresponding angle to an actuation device at the stern region.

A trimmable rudder system for a marine vessel such as a planing power boat, the system including a pair of rudder assemblies, each of which includes a rudder blade movably coupled to the hull by way of a ball-and-socket joint. Each rudder assembly includes a rudder shaft that extends from the rudder blade through the ball-and-socket joint and can be rotated for rotating the rudder blade to steer the power boat. Each rudder shaft may be operably coupled to a pair of actuators configured to control trim and camber positions of the rudder blade so that the pair of rudder blades can collectively achieve a desired hull trim change, including listing control and planing control of the power boat. Steering position, trim position, and camber position of the rudder blades may be simultaneously changed.

A trimmable rudder system for a marine vessel such as a planing power boat, the system including a pair of rudder assemblies, each of which includes a rudder blade movably coupled to the hull by way of a ball-and-socket joint. Each rudder assembly includes a rudder shaft that extends from the rudder blade through the ball-and-socket joint and can be rotated for rotating the rudder blade to steer the power boat. Each rudder shaft may be operably coupled to a pair of actuators configured to control trim and camber positions of the rudder blade so that the pair of rudder blades can collectively achieve a desired hull trim change, including listing control and planing control of the power boat. Steering position, trim position, and camber position of the rudder blades may be simultaneously changed.

The objective is to obtain an azimuth control apparatus and an azimuth control method that require no excessive memory capacity and calculation time for information processing and can cope with a disturbance by adaptively adjusting a control gain while calculating changing vessel parameters online. The vessel azimuth control apparatus has an azimuth control unit that outputs a steering-angle command signal for making a vessel turn to an azimuth to which the vessel should travel, based on an azimuth command signal generated by an azimuth command generation unit, a yaw-angle signal, and a yaw-angular-velocity signal, a steering-angle control unit that controls a rudder based on the steering-angle command signal, and a control gain adjustment unit that calculates respective frequency responses of the yaw-angle signal and the yaw-angular-velocity signal to a steering-angle signal outputted by a steering-angle detection unit and then adjusts a control gain of the azimuth control unit.

The objective is to obtain an azimuth control apparatus and an azimuth control method that require no excessive memory capacity and calculation time for information processing and can cope with a disturbance by adaptively adjusting a control gain while calculating changing vessel parameters online. The vessel azimuth control apparatus has an azimuth control unit that outputs a steering-angle command signal for making a vessel turn to an azimuth to which the vessel should travel, based on an azimuth command signal generated by an azimuth command generation unit, a yaw-angle signal, and a yaw-angular-velocity signal, a steering-angle control unit that controls a rudder based on the steering-angle command signal, and a control gain adjustment unit that calculates respective frequency responses of the yaw-angle signal and the yaw-angular-velocity signal to a steering-angle signal outputted by a steering-angle detection unit and then adjusts a control gain of the azimuth control unit.

A boat drive has an underwater housing (10) which is arranged outside of a boat hull (7) and can swivel relative to the boat hull (7) about a vertical swivel axis (11). In the housing at least one propeller shaft (13) is mounted and can be driven. A swivel drive mechanism is arranged in the inside space (6) of the boat hull (7) for swiveling the underwater housing (10) in order to control the driving direction of the boat. A zero-position mark (25) is provided on an element of the swivel drive mechanism, which facilitates easy determination of a zero position of the underwater housing (10).

An embodiment of a system for controlling a marine vessel includes a torque and/or position sensor configured to measure at least one of a torque applied by a steering wheel of the marine vessel and a rotational position of the steering wheel, and a processing device configured to receive a measurement of the steering wheel and electronically control a steering mechanism at a stern region of the marine vessel. The processing device is configured to estimate an angle of the steering wheel, determine a corresponding angle to be applied to the steering mechanism, and transmit a steering command based on the corresponding angle to an actuation device at the stern region.