Combining, among other things, suction cups and shower hoses, robotics researchers have created a flexible-bodied wall-climbing robot said to be inspired by one of nature's congenital suckers: the leech. Said robot, dubbed LEeCH for reasons we shall explore presently, can climb vertical surfaces in any direction and – notably – make the transition from one side of the wall to the other. The researchers are calling it a "world's first achievement in developing soft and flexible robot that is capable of free movement on a wall."

That name, then. If you squint, LEeCH might just about stand for Longitudinally Extensible Continuum-robot inspired by Hirudinea. Or so the researchers would have it. Hirudinea, if you're wondering, is the leech subclass of the Annelid phylum which also includes worms.

The robot draws inspiration from the land leech in particular. These are excellent climbers, thanks in no small part to the two natural suction cups at either end of their bodies. Being small, soft and light, leeches are able to survive falls from great height relatively unscathed. All admirable properties for a wall-climbing robot.

The robot next to the creature that inspire it Toyohashi University of Technology

And yet, it sounds as though the researchers may as easily have drawn inspiration from snakes. "I came up with the idea in the bathroom of my house," explains Ayato Kanada, lead author of the study. "The shower hose went wild as if it had a life when I inadvertently turned on the faucet at maximum. Then an idea occurred to me that if I could manipulate a hose, I might be able to make a robot with dynamic movement of living creature."

The use of shower hoses brings many of the advantages of the leech to the design, including being lightweight and flexible. And, like a leech, the robot can even stretch its body to a greater length. The hose is made to move back and forth by use of a gear, which connects to grooves on the surface of the hose, producing a rack and pinion mechanism. Vacuum pumps are used to control its suction cups.

Being able to climb both up and down, and side to side; as well as making the transition to the other side of the wall, the researchers say LEeCH is capable of total free movement on a vertical surface.

LEeCH makes the transition from one side of a wall to the other Toyohashi University of Technology

A press release to accompany the research talks up the possible applications of such technology, including building inspection and maintenance, and potentially search and rescue at disaster locations. However, the latter would need the robot to navigate uneven terrain. Thus far, LEeCH has stuck solely to flat surfaces.

The team is considering filling the hoses with liquids to change the stiffness of the robot as well as experimenting with more specialized suckers and additional muscles to carry out more complicated tasks. Currently off board, batteries and controllers will need to be built into the robot itself if it's ever to be used in the field.

The research team also included Dr. Tomoaki Mashimo of the Toyohashi University of Technology, and Dr. Fumiya Iida of the University of Cambridge. The team's research was published in Soft Robotics last month and can be read online.

You can see a video of the robot in action below.

Source: Toyohashi University of Technology