Avoidance-behavior determining method and avoidance-behavior determining device

An avoidance-behavior determining method comprising:

• calculating, by a processor, for each of a plurality of grids through which a track of a specific vessel passes, an angle of approach and an angle of exit of the track, respectively;
• extracting, by the processor, a grid for which the angle of approach and the angle of exit conform to a determining condition set for each of the grids, based on the determining condition;
• and
• determining, by the processor, whether the specific vessel has taken an avoidance behavior based on a relative distance from another vessel corresponding to a position of the specific vessel in a track in the extracted grid.

An avoidance-behavior determining device comprising:

• a processor that executes a process, the process comprising:
• calculating, for each of a plurality of grids through which a track of a specific vessel passes, an angle of approach and an angle of exit of the track, respectively;
• extracting a grid for which the angle of approach and the angle of exit conform to a determining condition set for each of the grids based on the determining condition;
• and
• determining whether the specific vessel has taken an avoidance behavior based on a relative distance from another vessel corresponding to a position of the specific vessel in a track in the extracted grid.