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.

A marine vessel maneuvering system includes an operator, propulsion device controllers each configured or programmed to control driving of a respective propulsion device based on an operation signal from the operator, a first communication bus to transmit the operation signal to some of the propulsion device controllers, a second communication bus to transmit the operation signal to a remainder of the propulsion device controllers excluding the some of the propulsion device controllers, and a gateway device to connect the first communication bus to the second communication bus such that the first communication bus and the second communication bus communicate with each other.

A controller for a watercraft controls first and second marine propulsion devices to start moving the watercraft by setting a first default angle, a second default angle, and a default thrust ratio as a first target rudder angle, a second target rudder angle, and a target thrust ratio respectively when a desired motion of the watercraft is straight sideways movement. The controller determines at least one of a first correcting angle, a second correcting angle, and a correcting thrust ratio to reduce an error between the straight sideways movement of the watercraft and an actual motion of the watercraft. The controller corrects the first target rudder angle, the second target rudder angle, and the target thrust ratio with the first correcting angle, the second correcting angle, and the correcting thrust ratio, respectively. The controller repeatedly detects the error and repeatedly updates the correcting angles and the correcting thrust ratio.

A method for controlling propulsion of at least two marine drives on a marine vessel includes monitoring an engine output indicator for each of the at least two marine drives on the marine vessel and detecting whether the engine output indicator for a subset of those at least two marine drives is below an expected value. If so, then an output restriction is imposed on at least one remaining marine drive not in the subset of marine drives, wherein the output restriction reduces an engine output of the at least one remaining marine drive to a predetermined level.

A marine vessel maneuvering system includes an operator to receive both a propulsive force operation to change a propulsive force of a propulsion device and a steering operation to turn the propulsion device to steer a marine vessel, and a controller configured or programmed to perform a control to automatically drive the propulsion device to move the marine vessel in an automatic marine vessel maneuvering mode. The controller is configured or programmed to perform a control to transition to the automatic marine vessel maneuvering mode based on a transition operation being performed on the operator.

A vessel speed control system includes a lever operator on which an operation is performed to increase or decrease a propulsion speed of the vessel, a transition operator on which a transition operation is performed to transition a normal operation mode to a speed control mode, and a controller configured or programmed to perform a control to prevent transition to the speed control mode even when the transition operation is performed on the transition operator during a restriction period of time including at least an acceleration/deceleration period of time during which a rotation speed of an engine or the propulsion speed of the vessel is changed by the lever operator in the normal operation mode.

A marine vessel maneuvering system includes a controller configured or programmed to perform a shift-out start control to control a shift actuator to immediately start an intermittent operation mode from a shift-out state when an intermittent operation switching control is performed to switch a normal operation mode in which a shift-in state continues to the intermittent operation mode in which the shift-in state and the shift-out state are repeated in a predetermined period of time based on a user's operation.

A marine propulsion system for a marine vessel includes a first marine propulsion device rotatable with respect to the marine vessel about at least one of a first steering axis and a first tilt-trim axis and a second marine propulsion device rotatable with respect to the marine vessel about at least one of a second steering axis and a second tilt-trim axis. A first control module controls operation of the first marine propulsion device, and a second control module controls operation of the second marine propulsion device. In response to one of the first and second marine propulsion devices being commanded to rotate about at least one of its respective first or second steering axis and its respective first or second tilt-trim axis, the respective first or second control module of the other of the first and second marine propulsion devices is turned ON.

Systems, methods, and devices for enhancing steering control of a personal watercraft. An electrically actuated device is coupled to the steering system of the personal watercraft and applies torque to the steering system. At least one sensor is positioned adjacent the steering system and generates operational data of the personal watercraft. At least one controller is coupled to the electrically actuated device and the at least one sensor, and is configured to determine a first torque to apply to the steering system based on the operational data responsive to a second torque being applied to the steering system. The at least one controller is further configured to operate the electrically actuated device to apply the first torque to the steering system for providing enhanced steering control of the personal watercraft, with the first torque being applied only by the electrically actuated device.

An operation device in a ship propulsion system including a ship propulsion machine, ship-mounted equipment, and a power supply, the operation device including a single push button switch and an operation processor performing processing. The operation processor detects a pressing mode of the push button switch when the push button switch is pressed while the ship-mounted equipment and the power supply are disconnected and the power source is stopped, performs processing of connecting the ship-mounted equipment and the power supply and starting the power source when the detected pressing mode is a first mode, and performs processing of connecting the ship-mounted equipment and the power supply while maintaining the power source in a stopped state when the detected pressing mode is a second mode.