Spontaneous switching of camphor motion between two chambers

The spontaneous motion of a solid scraping at an air/water interface was investigated under isothermal conditions. A spontaneously rotating camphor scraping moved between two connected chambers. To clarify the nature of this switching, the surface tension at the air/water interface was measured spatially. The essential features of the switching were reproduced by a computer simulation based on a partial differential equation. These results will be helpful for creating chemo-mechanical transduction and an artificial vectorial motor which mimics motor organs or organelles in living organisms under isothermal conditions.