Mode-emergence in the synchronized sailing of camphor boats

The synchronized self-motion of three camphor boats was investigated on a circular water route as a simple example of mode-emergence. When three camphor boats were floated on the surface of water in a circular route in the same direction, various kinds of synchronization could be produced by changing the inherent velocities of the boats. The essential features of synchronization were reproduced by a numerical calculation regarding the distances among three camphor boats, which changed the driving forces of the individual boats. We believe that the present results may be useful for developing novel experiments with vector processes and mode-switching.