How It Works: A Flexible, Pneumatic Robot Snake

One ingredient: baby powder
Screenshot from "CSAIL Robotic Arm Slithers Like A Snake Through Pipes" by MITCSAIL on YouTube

So Gizmodo found this morning a seafoam-green, pneumatic, snake/tentacle robot that’s able to wiggle its way through a simple, walled maze. Let’s take a look:

Yep, that’s impressive. But what is this for, exactly? And how does it work? The robot’s makers, a team of computer scientists from MIT, wrote up a paper that explains.

Researchers that build soft robots like this one hope that in the future, soft machines will be safer for humans to work with than hard metal ones. Softness and flexibility are also used in solving problems, such as snaking a robot through a complex space.

  • This is not meant to be a standalone robot. Instead, it’s a design for an arm on a larger machine. In the video, off to the left, you can see the arm needs to be connected to something that can do its computing for it. This machine provides it with the bursts of air it uses to bend.

  • The team wrote the robot arm’s control algorithms as a series of optimization problems with two main goals. The robot tries to reach a destination through the plastic maze while minimizing the number of times it hits the plastic walls. In 30 runs, the robot was able to reach its destination 24 times. Failures included problems like getting stuck in the maze.

  • The robot itself is made up of six modules stuck together. Everything is 100 percent silicone rubber. Each of the modules has a core of stiff rubber, laid between two hollow cylinders of softer rubber. Filling one of the cylinders with air makes the whole module bend either left or right (depending on which module is filled).

  • To further reduce the friction between the rubber robot and the plastic maze walls, the scientists rubbed the arm with talcum powder, the main ingredient in baby powder.