A vessel propulsion apparatus includes an engine that rotates a crankshaft in a forward rotation direction, a rotation speed detector that detects a rotation speed of the crankshaft, a propeller shaft coupled to a propeller, a shift switch that switches between a shift-in state and a neutral state, a shift state detector, an intake passage, a throttle valve, an intake pressure sensor, and a controller. The controller determines that the crankshaft is reversely rotating by an external force input from the propeller shaft when a predetermined reverse rotation recording condition is satisfied, and stores reverse rotation information. The reverse rotation recording condition includes a condition that an intake pressure after the shift switch switches from a neutral state to a shift-in state while the crankshaft rotates in the forward rotation direction is larger than a value equal to or higher than atmospheric pressure.

Various implementations described herein are directed to a non-transitory computer readable medium having stored thereon computer-executable instructions which, when executed by a computer, may cause the computer to receive an autopilot option selection for piloting a marine vessel. The computer may determine a first message corresponding to the autopilot option selection for a first autopilot. The computer may determine a second message corresponding to the autopilot option selection for a second autopilot. The computer may transmit the first message to the first autopilot. The computer may also transmit the second message to the second autopilot.

A power system for dynamic positioning of a vessel. The power system reduces fuel consumption, carbon buildup deposits and the risk of cylinder bore glazing while in combustion engine driven generators and provides an adequate protection against blackouts. The power system includes first and second combustion engine driven generators, a battery unit, and a converter unit arranged to provide power to the vessel from the battery unit. A first operational state of the power system in which the first combustion engine driven generator is arranged to deliver power to the vessel, and a second operational state, in which the first generator is subject to a fault, the second combustion engine driven generator arranged to deliver power to the vessel, and the converter unit is arranged to deliver power to the vessel during transition between the states.

A power system for dynamic positioning of a vessel. The power system reduces fuel consumption, carbon buildup deposits and the risk of cylinder bore glazing while in combustion engine driven generators and provides an adequate protection against blackouts. The power system includes first and second combustion engine driven generators, a battery unit, and a converter unit arranged to provide power to the vessel from the battery unit. A first operational state of the power system in which the first combustion engine driven generator is arranged to deliver power to the vessel, and a second operational state, in which the first generator is subject to a fault, the second combustion engine driven generator arranged to deliver power to the vessel, and the converter unit is arranged to deliver power to the vessel during transition between the states.

A robotic fish comprises one or more torque reaction engines and a fin, wherein the one or more torque reaction engines cyclically oscillate and is to cause one or more waves to propagate through the fin, wherein the one or more waves accelerating thrust fluid and propel the robotic fish. The robotic fish may have a shape of a flagellum, a fish, a marine mammal, or a disc. The one or more of the one or more torque reaction engines may comprise a drive shaft or may comprise no drive shaft. When the one or more of the one or more torque reaction engines comprises no drive shaft, the one or more of the one or more torque reaction engines may comprise a bearing surface of a closed ball-and-socket joint.

A robotic fish comprises one or more torque reaction engines and a fin, wherein the one or more torque reaction engines cyclically oscillate and is to cause one or more waves to propagate through the fin, wherein the one or more waves accelerating thrust fluid and propel the robotic fish. The robotic fish may have a shape of a flagellum, a fish, a marine mammal, or a disc. The one or more of the one or more torque reaction engines may comprise a drive shaft or may comprise no drive shaft. When the one or more of the one or more torque reaction engines comprises no drive shaft, the one or more of the one or more torque reaction engines may comprise a bearing surface of a closed ball-and-socket joint.