Autonomous cruising system, navigational sign identifying method, and non-transitory computer-readable medium

A method of identifying a navigational sign, comprising the steps of:

• capturing, by a camera installed in a ship, an image of an external environment of the ship;
• acquiring, by processing circuitry of a computer, from the camera, the image captured by the camera;
• identifying, by the processing circuitry of the computer, whether a mode of a lateral buoy included in the image is either one of a first mode and a second mode;
• determining, by the processing circuitry of the computer, a country to which a position of the ship detected by a position detector belongs, the position detector being configured to detect the position;
• and
• determining, by the processing circuitry of the computer, whether description of a sign of the lateral buoy is either one of a port sign and a starboard sign, from the mode of the lateral buoy and the determined country, based on a given correspondence relationship indicative of whether each of the first mode and the second mode corresponds to either one of the port sign and the starboard sign in the country.

A non-transitory computer-readable medium having stored thereon computer-executable instructions which, when executed by an autonomous cruising system that comprises a camera installed and a computer including processing circuitry, cause the autonomous cruising system to:

• capture, by the camera installed in the ship, an image of an external environment of the ship;
• acquire, by the processing circuitry of the computer, the image captured by the camera;
• identify, by the processing circuitry of the computer, whether a mode of a lateral buoy included in the image is either one of a first mode and a second mode;
• determine, by the processing circuitry of the computer, a country to which a position of the ship detected by a position detector belongs, the position detector being configured to detect the position;
• and
• determine, by the processing circuitry of the computer, whether description of a sign of the lateral buoy is either one of a port sign and a starboard sign, from the mode of the lateral buoy and the determined country, based on a given correspondence relationship indicative of whether each of the first mode and the second mode corresponds to either one of the port sign and the starboard sign in the country.