  Experimental studies were carried out on the motions and transformations of
liquid metal in ionic liquid under applied electric field. The induced vortex
rings and flows of ionic liquid were determined via the photographs taken
sequentially over the experiments. The polarization of electric double layer of
liquid metals was employed to explain the flow of ionic liquid with the
presence of liquid metal. Unlike former observation of liquid metal machine in
conventional solution, no gas bubble was generated throughout the whole
experiments, which makes it possible to encapsulate the liquid system for
fabricating soft robots.
