A human-like 3D-printed smart gel walks underwater. (Daehoon Han/Rutgers University-New Brunswick)

A 3D-printed smart gel that grabs objects and moves them could lead to soft robots that mimic sea animals like the octopus, which can walk underwater and bump into things without damaging them. Soft materials like the smart gel are flexible, often cheaper to manufacture than hard materials, and can be miniaturized.

Devices made of soft materials typically are simple to design and control compared with mechanically more complex hard devices. The 3D-printed hydrogel moves and changes shape when activated by electricity. The speed of the smart gel’s movement is controlled by changing its dimensions.