Researchers at MIT, Harvard University and Seoul National University have created a soft autonomous robot that moves via peristalsis much like a common earthworm would.
Peristalsis is the alternate squeezing and stretching of a muscle that causes a contraction like movement. Sangbae Kim, who was one of the inventors of the robot, said that in the future it could prove to be useful for navigating rough terrain, getting into tight spaces, for human prosthetics or endoscopes.
The Meshworm is incredibly resilient as you can see in the video, it is stepped on, hammered and it still creeps away unscathed. Kim said: “You can throw it, and it won’t collapse,” he continued “Most mechanical parts are rigid and fragile at small scale, but the parts in Meshworms are all fibrous and flexible. The muscles are soft, and the body is soft … we’re starting to show some body-morphing capability.”
The artificial ‘muscle’ that enables the Meshworm to move, is made from nickel and titanium. It is a shape-memory alloy that contracts and stretches with heat and it was wound around the tubing creating segments along the length of it, very similar to those found in an earthworm. A small current was then applied to the wire causing it to squeeze the mesh tube and propel the robot forward.
The tubing that makes up the body of the Meshworm was created by rolled up polymer mesh that was heat-sealed. This material allows the tube to stretch and contract, much like a spring.
For many years now researchers have been working on ways to create soft robotic systems, hoping that creating a robot that lacked the usually bulky hardware would help them to explore tight spaces or travel over difficult terrain. A soft robot would also be better for human interaction and could prove to be useful in the design of implants or prosthetics.