A group of mechanical engineers at Stanford has created a transparent robot that looks and behaves like a worm, elongating its body in order to move. Using a pneumatic control system, an operator can make the bot turn corners and even squeeze itself through a narrow crack between two pieces of sticky flypaper. In the crowded field of soft robotics, this strange creature is one of the most intriguing.

Mechanical-engineering researcher Elliot Hawkes and his team designed the robot for a variety of applications, including search and rescue. In a recent issue of Science Robotics, they explain that the bot could also be used to create instant 3-D structures like a spiral-shaped antenna.

Made from thin polyethylene, the robot expands from its tip by eversion. A pump pushes air into the bot’s tube-shaped body, and this pressure forces more of the plastic membrane to unwind from a reel inside the robot’s tail.

Modeled on the body structures of invertebrates like worms, the group’s experimental system can grow from 28cm to 72m, and it is limited only by the amount of plastic membrane on the reel. The bot can move relatively quickly while extending, though its range of movement is of course bounded by the length of its body.

Operators can maneuver the robot, write the researchers, “when the relative lengths of the sides of the vessel are controlled while everting.” The robot has inflatable chambers that run along its sides. To turn left, operators would inflate the right chamber, thus lengthening the right side of its body as its skin continues to unspool. This forces a left-hand turn.

Though the robot may be limited in length, the researchers point out that its body is “inexpensive and disposable,” so “many parallel bodies, like a single branched body, could cover large areas for search-and-rescue applications.” They write that this bot’s growth imitates that of pollen tubes, fungus, algae, and root hairs.

Describing these robots really doesn’t do them justice, however. You really have to check out the videos showing how they work. They’re perfect for installing sensors in hard-to-reach places, guiding water hoses, and, of course, sending a camera through tiny cracks. As long as these bots are working with the good guys, we’ll be just fine.

Science Robotics, 2017. DOI: 10.1126/scirobotics.aan3028

Listing image by Elliot Hawkes et al.