A boat comprises a hull, a primary steering mechanism carried by the hull, a control station located on the hull, a helm located at the control station, and a thruster system carried by the hull. The primary steering mechanism, such as a rudder, is operable via the helm with a helm input being derived from operation of the primary steering mechanism thereby. The thruster system includes at least one thruster mounted to the hull, distinct from the primary steering mechanism, and a controller. The controller receives the helm input and is configured with program instructions to operate the at least one thruster responsive to the helm input to supplement a corresponding movement of the hull. The controller can also automatically operate the thruster responsive to direction, speed and ballast inputs.

A propulsion system and propulsion control method for a marine vessel is configured to detect a steering position of at least one propulsion device, determine a difference between the detected steering position and a centered steering position, and require, by a controller, that the detected steering position be within a threshold range of the centered steering position prior to enabling a joystick thrust control mode wherein thrust by the at least one propulsion device is controlled based on user input at a joystick.

A thruster system for improved steering and maneuverability of a marine vessel when operating at relatively low, or wakeless speeds, such as in the vicinity of docks, swimmers or other obstacles, or when trailering, beaching or mooring. The thruster system has a modularized design adapted to independently control separate motor/propeller units located at various positions on the vessel's hull. Each propeller of the modular thruster motor system has its own relatively small, electric motor and mounting bracket, permitting each motor to be separately mounted to a location on the hull of the marine vessel apart from other thruster motors. The thruster system is further enhanced by an electrical control system for controlling each modular thruster motor system of the thruster system. In some embodiments, a charging system is provided that permits each electrical control system to be separately charged from the marine vessel's main battery.

A thruster system for improved steering and maneuverability of a marine vessel when operating at relatively low, or wakeless speeds, such as in the vicinity of docks, swimmers or other obstacles, or when trailering, beaching or mooring. The thruster system has a modularized design adapted to independently control separate motor/propeller units located at various positions on the vessel's hull. Each propeller of the modular thruster motor system has its own relatively small, electric motor and mounting bracket, permitting each motor to be separately mounted to a location on the hull of the marine vessel apart from other thruster motors. The thruster system is further enhanced by an electrical control system for controlling each modular thruster motor system of the thruster system. In some embodiments, a charging system is provided that permits each electrical control system to be separately charged from the marine vessel's main battery.

A hybrid ship propulsion machine includes an internal-combustion-drive propulsion part and an electric propulsion part. The electric propulsion part is attached to a first housing part of the internal-combustion-drive propulsion part, and is disposed at a position higher than an anti-cavitation plate of the internal-combustion-drive propulsion part such that a second propeller of the electric propulsion part sinks below a water surface during low-speed movement, which is not a planing state of a ship, and the second propeller comes out of the water surface during planing of the ship.

A sealing assembly for a stem tube implemented in a retractable thruster system and the retractable thruster system therefor. The sealing assembly comprises an annular sealing housing. The annular sealing housing comprising a first sealing layer, arranged at an opening of the annular sealing housing, configured to prevent marine growth and fluid ingress, a second sealing layer, arranged after the first sealing layer, configured to form a water-tight seal against the stem tube, a third sealing layer, arranged after the second sealing layer, configured to accommodate relative movement of the stem tube, a fourth sealing layer, arranged between the first sealing layer and the second sealing layer, configured to be inflated for providing a temporary sealing barrier; and a drainage channel, arranged between the first sealing layer and the second sealing layer, configured to provide a dedicated path for removal of fluid ingress from the annular sealing housing.

A watercraft propulsion system includes a bow thruster to generate a lateral propulsive force, a propulsion device on a stern of a hull and having a variable steering angle, and a controller configured or programmed to control the bow thruster and the propulsion device to perform a fixed point holding control to maintain a position and an azimuth of the hull. The fixed point holding control includes a translation mode in which the hull position is maintained by controlling the propulsive force of the propulsion device with the steering angle set to a translation mode steering angle and the hull azimuth is adjusted by controlling the propulsive force of the bow thruster, and a bow turning mode in which the hull azimuth is adjusted by controlling the propulsive forces of the bow thruster and the propulsion device with the steering angle set to a bow turning mode steering angle.

A thruster system for improved steering and maneuverability of a marine vessel when operating at relatively low, or wakeless speeds, such as in the vicinity of docks, swimmers or other obstacles, or when trailering, beaching or mooring. The thruster system has a modularized design adapted to independently control separate motor/propeller units located at various positions on the vessel's hull. Each propeller of the modular thruster motor system has its own relatively small, electric motor and mounting bracket, permitting each motor to be separately mounted to a location on the hull of the marine vessel apart from other thruster motors. The thruster system is further enhanced by an electrical control system for controlling each modular thruster motor system of the thruster system. The electrical control system includes a control mechanism integrated with the steering wheel and/or throttle of the marine vessel and operates independently of the main propulsion and steering systems of the marine vessel.