The problem with motion and conventional robots is that hard joints don’t just allow movement, and they restrict the range of motion. So Biomimetic Technologies for Soft-bodied Robots project is trying to make an ersatz caterpillar that will move around in pretty much the same way as the real thing. The researchers see the potential to use the squishable, relatively simple creations to find land mines, repair machinery in hard-to-reach spots and even diagnose and treat diseases. So Dr. Trimmer comes from the field of neurobiology, suggests that much of the secret of locomotion is inherent in the muscles and the body. The researchers are seeking a similar elegance in their creations. The initial creatures by researchers were hollow tubes. The “muscles” are wire springs made from shape-memory alloy. Electrical current heats the springs, causing them to constrict; once the current stops, the elastic skin stretches the wire back into its resting shape.

The skin is a silicone rubber and its composition can be manipulated so that it can be leathery-tough or supple and clammy.
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