Skynet's liquid metal T-1000 robot seemed fantastical when the Terminator 2: Judgement Day movie was released in 1991. Fast forward 30 years, however, and researchers at the Chinese Academy of Sciences have created early renditions of shapeshifting soft robots made of liquid gallium infused with magnetic neodymium-iron-boron microparticles.

The "robot" is made up of magnetic pixels – particle...