Fig. 3. Physical shape changes of soft autonomous robots in response to environmental inputs.

(A) The extension ratio ε of the pneumatic actuator and the robot (without any control modules) as a function of applied pressure. (B) Multiple types of modular control units are developed. They can be easily attached to or removed from the body of the robot. (C) As one example, a control module can sense and respond to heat or light. (D) In this example, a different control module design causes the robot to bend away from heat or solvents. (E and F) In another example, a control module is designed to bend the robot so that its end will align toward a light. Scale bars (A), (C), (D), (E) and (F), 2 cm.