This disclosure provides improved nautical craft that can travel and navigate on their own. A hybrid vessel is described that converts wave motion to locomotive thrust by mechanical means, and also converts wave motion to electrical power for storage in a battery. The electrical power can then be tapped to provide locomotive power during periods where wave motion is inadequate and during deployment. The electrical power can also be tapped to even out the undulating thrust that is created when locomotion of the vessel is powered by wave motion alone.

An exemplary method for a marine vessel having a propeller mounted to a rotatable shaft for converting rotative shaft power transferred from the shaft to the propeller into thrust to propel the marine vessel across water, includes obtaining measurement values that are descriptive of the shaft power, the thrust and speed through water of the marine vessel; separately estimating at least one of first excess shaft power caused by fouling of the propeller and second excess shaft power caused by fouling of the hull of the marine vessel; and issuing an indication of propeller cleaning in dependence of the first excess shaft power and hull cleaning in dependence of the second excess shaft power.

An exemplary method for a marine vessel having a propeller mounted to a rotatable shaft for converting rotative shaft power transferred from the shaft to the propeller into thrust to propel the marine vessel across water, includes obtaining measurement values that are descriptive of the shaft power, the thrust and speed through water of the marine vessel; separately estimating at least one of first excess shaft power caused by fouling of the propeller and second excess shaft power caused by fouling of the hull of the marine vessel; and issuing an indication of propeller cleaning in dependence of the first excess shaft power and hull cleaning in dependence of the second excess shaft power.

The present disclosure relates to a method for determining the working life of a traction battery of a boat, including the steps of determining a system configuration and/or operating conditions of the boat, providing a traction battery model, which states an ageing condition of the traction battery as time progresses depending on the system configuration and/or operating conditions determining at least one condition that confirms the end-of-life condition of the traction battery has been reached and calculating the time-period until the end-of-life condition is reached on the basis of the traction battery model.

The present disclosure relates to a method for determining the working life of a traction battery of a boat, including the steps of determining a system configuration and/or operating conditions of the boat, providing a traction battery model, which states an ageing condition of the traction battery as time progresses depending on the system configuration and/or operating conditions determining at least one condition that confirms the end-of-life condition of the traction battery has been reached and calculating the time-period until the end-of-life condition is reached on the basis of the traction battery model.

A ship vicinity information display device is provided, which is capable of displaying a position etc. of a destination of another ship based on information of the destination obtained from the other ship, in a mode which is intuitively easy to understand. A radar indicator may include a display unit, an AIS interface, and processing circuitry. The display unit may be capable of displaying an image of a situation in the vicinity of one ship. The AIS interface may receive the information of the destination of the other ship. The processing circuitry may acquire a longitude and latitude of the destination based on the destination information of the other ship and graphically display at least one of the position of the destination of the other ship and a direction of the destination from the other ship (other-ship destination symbol), on the display unit.

A trolling device for a boat includes a trolling motor and a control mechanism. The control mechanism controls at least one of the speed and the direction of the trolling motor. The control mechanism is configured to receive control instructions from an electronic GPS mapping computer to cause the trolling motor to maintain a controlled drift of the fishing boat with respect to an anchor point, water current rate, water current direction, wind, and/or wave action.

A trolling device for a boat includes a trolling motor and a control mechanism. The control mechanism controls at least one of the speed and the direction of the trolling motor. The control mechanism is configured to receive control instructions from an electronic GPS mapping computer to cause the trolling motor to maintain a controlled drift of the fishing boat with respect to an anchor point, water current rate, water current direction, wind, and/or wave action.

To provide a motion control device for a ship, which does not require adjustment of weights of an performance function, and is less liable to fail in control calculation by building optimization calculation only into a part of classical feedback control, the motion control device, which is configured to cause a ship, on which a plurality of outboard engines are installed, to cruise along a desired trajectory, includes: a trajectory generator configured to output a trajectory command; a controller configured to output a control force command based on the trajectory command and a sensor information group output from a sensor group provided for the ship; and a control force distributor configured to carry out, based on the control force command, optimization calculation for operation amounts required for the plurality of outboard engines in accordance with a constraint condition set in advance so as to output the operation amounts.

To provide a motion control device for a ship, which does not require adjustment of weights of an performance function, and is less liable to fail in control calculation by building optimization calculation only into a part of classical feedback control, the motion control device, which is configured to cause a ship, on which a plurality of outboard engines are installed, to cruise along a desired trajectory, includes: a trajectory generator configured to output a trajectory command; a controller configured to output a control force command based on the trajectory command and a sensor information group output from a sensor group provided for the ship; and a control force distributor configured to carry out, based on the control force command, optimization calculation for operation amounts required for the plurality of outboard engines in accordance with a constraint condition set in advance so as to output the operation amounts.