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.

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.

A method for using a system including a plurality of first fields and a plurality of second fields fixed to a first device and presenting a first physical characteristic and a second physical characteristic, respectively, the first and second fields being arranged in an alternating manner. First and second sensors are fixed to the second device and arranged to move along the array of fields when the second device moves in relation to the first device. The method includes detecting, by the first sensor and during a movement of the second device in relation to the first device, a transition from the first to the second physical characteristic, or vice versa, simultaneously detecting, by the second sensor, the first or the second physical characteristic, and determining, based on the detected transition and physical characteristic, the direction of movement of the second device in relation to the first device.

A watercraft, associated motor pod, and associated methods are provided. The motor pod is operable to maintain an orientation of the watercraft relative to a reference datum while the watercraft is moving or stationary.

A marine propulsion system for a marine vessel has an outboard motor including a cowl covering an internal combustion engine that powers the outboard motor and an accelerometer mounted to the outboard motor. A control module is communicatively connected to the accelerometer. The control module receives information regarding an acceleration of the outboard motor from the accelerometer. The control module uses the information regarding the acceleration of the outboard motor to do at least one of the following: determine an angle of the outboard motor with respect to gravity; determine an amount of oil in an oil sump of the outboard motor; and determine if a reading of the amount of oil in the oil sump is accurate.

The invention relates to a propeller arrangement in a cathodic protection system for a marine vessel with a marine propulsion system, which cathodic protection system comprises a direct current power source with a positive terminal. The propulsion system comprises at least one driveline housing at least partially submerged in water; a torque transmitting drive shaft extending out of the driveline housing; and at least one propeller mounted on the drive shaft. According to the invention, the at least one propeller is electrically isolated from its drive shaft. Each electrically isolated propeller is electrically connected to a slip ring connector, which slip ring connector is in electrical connection with the positive terminal. The invention further relates to a vessel provided with such a propeller arrangement.

A posture control system for a hull includes a movable posture control plate. An outboard motor is attached to the hull and is movable with respect to the hull. A controller is configured or programmed to control movement of the posture control plate and movement of the outboard motor so as to control the posture of the hull.

A marine engine comprises a powerhead having an engine block, a cylinder head and a crankcase containing a crankshaft. Operation of the marine engine causes rotation of the crankshaft. A crankcase cover encloses the crankshaft in the crankcase. A supercharger is on the crankcase cover, the supercharger being configured to provide charge air for combustion in the powerhead. The supercharger comprises a charge air outlet for conveying charge air from the supercharger for combustion in the powerhead, the charge air outlet being oriented so as to discharge the charge air towards the powerhead.

A controller generates a first forward thrust with a first propulsion device and generates a first backward thrust with a second propulsion device with a same number as the first propulsion device in case that the backward thrust is less than a predetermined threshold. The controller generates a second forward thrust larger than the first forward thrust with the first propulsion device and generates a second backward thrust with each of the second propulsion devices greater than the first propulsion device in case that the backward thrust is greater than or equal to the predetermined threshold.

An anti-fouling arrangement in a marine vessel with a marine propulsion system, the propulsion system comprising at least one driveline housing, a torque transmitting drive shaft extending out of the driveline housing, and at least one propeller mounted on the drive shaft. The at least one propeller is electrically isolated from its drive shaft, wherein each electrically isolated propeller is connected to a positive terminal of a direct current power source, and each metallic component to be protected against fouling is connected to a negative terminal of the direct current power source. A control unit is arranged to regulate the voltage and current output from the direct current power source.