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This Origami Robot, Created in Harvard, Can Slither Like A Snake

A group of researchers from the Harvard John A. Paulson School of Engineering and Applied Sciences (SEAS) have designed an inflatable, origami robot that can crawl like a snake. The skin of this bot looks like an origami snakeskin, allowing it to slither across the ground.

“There has been a lot of research in recent years into how to fabricate these kinds of morphable, stretchable structures,” says Ahmad Rafsanjani, a postdoctoral fellow at SEAS, who has spent several months on this project to design and develop this bot.

“We have shown that kirigami principles can be integrated into soft robots to achieve locomotion in a way that is simpler, faster and cheaper than most previous techniques.”

According to Rafsanjani, he researched about fifty designs and then finally arrived at the best possible layout and shape to enable this creepy robot move with the least effort.

The design of this snake robot is inspired by kirigami, the Japanese traditional art of paper cutting. The researchers used laser to cut small scales (tiny flaps) into the robot’s body that allow it to move on a surface. The main core of the robot is a tube that can be inflated (mostly lengthwise) by pumping air into it.  When the tube expands, tiny scales on the outer body of the robot allow it to push forward. Therefore, by exerting a little amount of effort, the snake robot moves effortlessly across uneven surfaces.

“This pattern, when you stretch it, some parts go up and some parts go down,” says Rafsanjani.

“So we came up with some new designs, which is basically unidirectional kirigami features. They all go in one direction.”

However, when the robot moves, it appears more like a wiggling worm or slug than a legless reptile.

According to its developers, a robot with this specific design can have plenty of applications. It can crawl into tight spaces or holes that are difficult to reach. This machine can has potential to be a cheap alternative to other expensive microbots that have been developed in the past years and are capable of moving through hard to reach areas with a lot more dexterity.

This robot also seems like a clever development in the field of soft robotics, where air or oil is used to make a robot move.

Traditional robots use electric motors (actuators) for the movement of the robot.

According to Harvard researchers, the efficiency of their bot’s movement depends on the shape of the scales cut. Trapezoidal scales have better efficiency in terms of bot’s movement compared to circular and triangular scales.

“If you look at the belly scales of snakes, they look more trapezoidal,” says Rafsanjani.

“It comes to mind that if you have more surface area, there’s more contact. So if you have a very rough surface, there’s more chance to grab.”