Steering control device that makes control of a steering mode of marine vessel, method thereof, and marine vessel

A marine vessel comprising:

• a steering control device;
• a steering wheel having a rotatable angle in a left rotation direction limited to a first angle position, and a rotatable angle in a right rotation direction limited to a second angle position, and including steering modes including a normal steering mode and an automatic steering mode;
• at least one memory to store a set of instructions;
• and
• at least one processor configured or programmed to execute the set of instructions to:
• acquire a rotation angle position of the steering wheel;
• acquire a start instruction of the automatic steering mode to allow the marine vessel to be automatically steered without depending on a rotation operation of the steering wheel and automatically steered without depending on input by a vessel user;
• and
• perform a control operation to shift the steering mode to the automatic steering mode in response to acquisition of the start instruction in the normal steering mode, and to shift the steering mode to the normal steering mode in response to a change in the rotation angle position of the steering wheel beyond a threshold angle in the automatic steering mode;
• wherein
• during the control operation, in the normal steering mode, the at least one processor is configured or programmed to not shift the steering mode to the automatic steering mode even when the start instruction is acquired in a case where a difference between the acquired rotation angle position of the steering wheel and the first angle position is smaller than a first predetermined angle amount, or in a case where a difference between the acquired rotation angle position of the steering wheel and the second angle position is smaller than a second predetermined angle amount.

A steering control method for a marine vessel including a steering wheel having a rotatable angle in a left rotation direction limited to a first angle position, and a rotatable angle in a right rotation direction limited to a second angle position, the marine vessel including steering modes including a normal steering mode and an automatic steering mode, the steering control method comprising:

• acquiring a rotation angle position of the steering wheel;
• acquiring a start instruction of the automatic steering mode to allow the marine vessel to be automatically steered without depending on a rotation operation of the steering wheel and automatically steered without depending on input by a vessel user;
• and
• performing a control operation to shift the steering mode to the automatic steering mode in response to acquisition of the start instruction in the normal steering mode, and to shift the steering mode to the normal steering mode in response to a change in the rotation angle position of the steering wheel beyond a threshold angle in the automatic steering mode;
• wherein
• during the control operation, in the normal steering mode, controlling so as not to shift the steering mode to the automatic steering mode even when the start instruction is acquired in a case where a difference between the acquired rotation angle position of the steering wheel and the first angle position is smaller than a first predetermined angle amount, or in a case where a difference between the acquired rotation angle position of the steering wheel and the second angle position is smaller than a second predetermined angle amount.