A watercraft includes a hull, a wave detector to detect wave conditions on a water surface, a trim adjuster to adjust a trim angle of the watercraft, and a controller. The controller is configured or programmed to determine, based on a detection value of the wave detector, whether or not the water surface is smooth and, if it is determined that the water surface is not smooth, control the trim adjuster to increase the trim angle.

A watercraft includes a hull, an engine to generate power to propel the hull, an engine speed sensor to detect the rotation speed of the engine, and an ON/OFF sensor to be turned on and off according to a vertical acceleration of the hull. The watercraft further includes a controller configured or programmed to determine, based on at least one of a detection value of the ON/OFF sensor and a detection value of the engine speed sensor, whether or not a water surface is smooth.

The present disclosure relates to a vessel propelling mechanism. In one aspect, a vessel propelling system includes a motor and a waterjet system. The waterjet system is coupled to the motor and includes a stator with a plurality of blades. A first blade of the plurality of blades has a shape that is different than remaining blades of the plurality of blades, the shape of the first blade allowing a driving mechanism of the motor to be coupled to a shaft within the waterjet system.

The present disclosure relates to a vessel propelling mechanism. In one aspect, a vessel propelling system includes a motor and a waterjet system. The waterjet system is coupled to the motor and includes a stator with a plurality of blades. A first blade of the plurality of blades has a shape that is different than remaining blades of the plurality of blades, the shape of the first blade allowing a driving mechanism of the motor to be coupled to a shaft within the waterjet system.

An accelerating ducted propeller system for propelling boats offers enhanced performance, having the front end of the nozzle disposed at a radial distance (H) between 0.045D and 0.082D from the inner radius of the nozzle, where D is the inner diameter of the nozzle. The front end of the chord of the axial profile of the nozzle has a larger radius than the rear end of the chord with respect to the axis of rotation of the propeller. The inner surface of the nozzle at the axial distance (J) of 0.025D from the rear end of the output edge of the nozzle is at a radial distance from the inner radius of the nozzle of more than 0.0040D and less than 0.0300D. The radial difference between the inner radius of the nozzle and the outer radius of the profile of the nozzle is less than 0.092D.

An axial flux propulsion system for an electric boat that includes interconnecting subsystems including a mounting system, a traction system, a transmission system, an electrical power distribution system, a control system, and a fluid management system, among other boat systems. The traction system typically is an axial flux motor/generator. Various embodiment of the axial flux propulsion system may include a stern drive embodiment and a jet drive embodiment. Portions of the axial flux propulsion system may be both inboard and outboard. A control system may control the operation of the various boat systems including the axial flux motor/generator, and as a result, control the overall operation of the boat.

An axial flux propulsion system for an electric boat that includes interconnecting subsystems including a mounting system, a traction system, a transmission system, an electrical power distribution system, a control system, and a fluid management system, among other boat systems. The traction system typically is an axial flux motor/generator. Various embodiment of the axial flux propulsion system may include a stern drive embodiment and a jet drive embodiment. Portions of the axial flux propulsion system may be both inboard and outboard. A control system may control the operation of the various boat systems including the axial flux motor/generator, and as a result, control the overall operation of the boat.

The invention relates to a method for controlling a water jet propulsion device for the propulsion of a marine vessel, the water jet propulsion device comprising: a conduit extending between an inlet and an outlet; an impeller in the conduit; and a mechanical power provider arranged to deliver power to the impeller; the method comprising receiving a plurality of thrust commands, and controlling a thrust level of the water jet propulsion device in dependence the thrust commands, wherein controlling the thrust level comprises adjusting a position of a deflector arranged to deflect water flowing out of the outlet, characterised by coordinating the adjustment of the position of the deflector with a level of engagement of a clutch, arranged to adjust the delivery of power from the power provider to the impeller, so that the thrust level is substantially continuous in a thrust command domain.

The invention relates to a method for controlling a water jet propulsion device for the propulsion of a marine vessel, the water jet propulsion device comprising: a conduit extending between an inlet and an outlet; an impeller in the conduit; and a mechanical power provider arranged to deliver power to the impeller; the method comprising receiving a plurality of thrust commands, and controlling a thrust level of the water jet propulsion device in dependence the thrust commands, wherein controlling the thrust level comprises adjusting a position of a deflector arranged to deflect water flowing out of the outlet, characterised by coordinating the adjustment of the position of the deflector with a level of engagement of a clutch, arranged to adjust the delivery of power from the power provider to the impeller, so that the thrust level is substantially continuous in a thrust command domain.

A built-in propulsion system includes an engine, a diversion unit with a diversion base and an exhaust pipe, and a propulsion unit. The diversion base is connected to the engine, having a water inlet, a water outlet, a diversion channel in communication between the water inlet and the water outlet, a shaft hole above the water inlet and an exhaust chamber behind the shaft hole. The exhaust pipe is fixed on the outer periphery surface of the diversion base in communication with the exhaust chamber. The propulsion unit includes a transmission shaft inserted through the shaft hole and connected to the engine, and an impeller located in the diversion channel and connected to the transmission shaft. The exhaust pipe is used to exhaust the exhaust gas of the engine to the outside of the diversion base to avoid the interference of the exhaust gas and the water flow.