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Updated: May 14, 2026

Visually Based Characterization of the Incipient Particle Motion in Regular Substrates: From Laminar to Turbulent Conditions
Published on: February 22, 2018
Spontaneous motion of an elliptic camphor particle
Hiroyuki Kitahata1, Keita Iida, Masaharu Nagayama
1Department of Physics, Graduate School of Science, Chiba University, Chiba 263-8522, Japan. kitahata@physics.s.chiba-u.ac.jp
Abstract:
The coupling between deformation and motion in a self-propelled system has attracted broader interest. In the present study, we consider an elliptic camphor particle for investigating the effect of particle shape on spontaneous motion. It is concluded that the symmetric spatial distribution of camphor molecules at the water surface becomes unstable first in the direction of a short axis, which induces the camphor disk motion in this direction. Experimental results also support the theoretical analysis. From the present results, we suggest that when an elliptic particle supplies surface-active molecules to the water surface, the particle can exhibit translational motion only in the short-axis direction.
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