Here is a soft, transforming robot designed by Standford Engineers that can change shape and move without a source of energy or air. The isoperimetric robot borrows features of soft, truss, and collective robots.
As Standford explains:
To make a more complex version of the robot, the researchers simply attach several triangles together. By coordinating the movements of the different motors, they can cause the robot to perform different behaviors, such as picking up a ball by engulfing it on three sides or altering the robot’s center of mass to make it roll.
The above video gives you a better idea how this isoperimetric robot works.