Biomimetic locomotion study of floating microswimmers with light-driven particle hinges on water/air interface*

Microswimmers with individually light-driven hinges are studied experimentally in the form of two-hinge and four-hinge “Purcell” swimmers for their capability to reproduce biomimetic locomotion on a water/air interface through lateral propulsion. Floating microswimmers hold great potential in applications of active environmental monitoring and miniaturized cargo transportation but are currently hindered by the availability of locomotion and maneuverability on a millimeter/micrometer scale. Light and magnetic fields have been used in driving previous microswimmers, but unless the application of external stimuli has a fine spatial and temporal resolution, individually driven hinges of similar characteristics are impossible. In this study, an electromicrofluidic (EMF) printing platform, that independently drives and assembles hydrogel droplets and suspended particles, is adapted to fabricate hydrogel Purcell swimmers with color-varied particle-embedded hinges driven by light. The responsiveness of the differently colored hinges to the exposure of light and the two-dimensional movement of the microswimmers will be characterized and compared to similar biomimetic movement.