Self-propulsion

Self-propulsion is the autonomous displacement of nano-, micro- and macroscopic natural and artificial objects, containing their own means of motion.[2][3][4][5][6][7] Self-propulsion is driven mainly by interfacial phenomena.[8] Various mechanisms of self-propelling have been introduced and investigated, which exploited phoretic effects,[9] gradient surfaces, breaking the wetting symmetry of a droplet on a surface,[10][11] the Leidenfrost effect,[12][13][14] the self-generated hydrodynamic and chemical fields originating from the geometrical confinements,[15] and soluto- and thermo-capillary Marangoni flows.[16][17][1] Self-propelled system demonstrate a potential as micro-fluidics devices[18] and micro-mixers.[19] Self-propelled liquid marbles have been demonstrated.[14]

The sequence of images demonstrating the rotation of the self-propelled PVC tubing, containing camphor.[1] The time separation between frames is 0.33 s.