Gifted Unit on Origami and Sadako & the Thousand Paper Cranes Novel Study
Origami Robots
Ingestible Origami Robot
Robot unfolds, removes button battery from simulated stomach.
MIT Technology Review June 21, 2016
Larry Hardesty
In experiments involving a simulation of the human esophagus and stomach, researchers at MIT, the University of Sheffield, and the Tokyo Institute of Technology have demonstrated a tiny origami robot that can unfold itself from a swallowed capsule and crawl along the stomach wall to patch a wound or remove a swallowed button battery. Every year, 3,500 swallowed button batteries are reported in the U.S. alone. The batteries can cause a chemical reaction that can lead to disfigurement and even death.
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The robot propels itself chiefly through a “stick-slip” motion, in which its appendages stick to a surface through friction when it executes a move but slip free when its body flexes to change its weight distribution. It can also push against fluid like an oar.
The robot is rectangular, with accordion folds perpendicular to its long axis and pinched corners that act as points of traction. In the center of one fold is a permanent magnet that responds to changing external magnetic fields, which control the robot’s motion.
Origami Robots in Action
A tiny origami robot robot ingested in a capsule can unfold itself and be directed by external magnetic fields to retrieve batteries in a simulated human esophagus and stomach.
Origami robots were first designed by researchers at MIT’s Computer Science and Artificial Intelligence Laboratory (CSAIL), and can form any three-dimensional shape based on a distinct pattern of slits on a semi-rigid layered plastic sheet. They have been successful in designing tiny origami robots made of various materials like polyvinylchloride and polystyrene that self-assemble using a folding process triggered by heat. Once folded, the robots can run, carry items, swim, and clear obstacles. When the task has been completed, they can recycle themselves by dissolving in a liquid.
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Researchers in the CSAIL group have been in the process of optimizing these robots for years, and have recently designed one that, after unfolding from a swallowed capsule, can retrieve batteries and patch consequent wounds in the stomach. Their new ingestible robot is made of dried pig intestine which is a biocompatible material typically used for sausage casings. The structure of the robot is rectangular in shape with accordion folds and pinched corners. A magnet on top of one of the folds is critical to the robots movement, allowing it to be directed by applied and changing magnetic fields. The robot’s movement is described by researchers as a ‘stick-slip’ motion, where its appendages ‘stick’ to a surface using friction when it needs to move, and ‘slips’ free when it redistributes its weight. However, since the stomach is typically filled with fluids, the ingestible origami robot also can propel itself through liquid, using fins present on its body.
Over 3500 button batteries are swallowed every year in the U.S., and while most are digested normally, they can burn the stomach tissue with prolonged contact. In an experiment to simulate the retrieval of a button battery from a stomach, the researchers created a synthetic stomach and esophagus based on the mechanical properties of a pig stomach, and filled it with lemon juice and water to simulate the acidic stomach environment. The ingestible origami robot was enclosed in an ice capsule, moved down the simulated esophagus, and unfolded into its functional form once the capsule is melted in the stomach. Once unfolded, the robot was controlled using an external magnetic field to navigate to the battery and lift it away from the stomach lining. No longer attached to the stomach lining, the battery could then be naturally eliminated.
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The ingestible origami robot has huge potential applications to healthcare. The team at CSAIL hope to apply their technology to remove other foreign objects from the body and treat resulting wounds by delivering medicine. Their next step is to test their robot in vivo (in the body of a living organism), attach sensors to it, and design a prototype that can move on its own without an external magnetic field.
Written By: Fiona Wong, PhD
Origami Robots Transform Like Optimus Prime
By Andrew Wagner, September 27, 2017
In a move sure to please sci-fi geeks, scientists have created a new robot that can change shape to become a wheel, a ship, and even a glider, similar to the robots of Transformers and Robotech. What starts as an unassuming metal cube quickly grows into a versatile robot, using origamilike layers of thin mylar plastic that it folds around itself. The bot’s transformation starts when a magnetically controlled cube 3 millimeters square drops onto a thin, 2-centimeter-long mylar sheet with precisely placed folds and slits. Scientists heat the sheet, which folds itself around the block (nicknamed “Primer”) in a pattern that allows it to shuffle quickly across a flat surface. Like a Russian nesting doll, there are four origami exoskeletons that can further surround this “walk-bot” to perform different tasks, including one shaped like a pair of wheels and another shaped like glider wings. There’s even a ship-shaped exoskeleton that allows the bot to float on water. When the walk-bot needs to shed one of these outer layers, it simply submerges itself underwater, and the metallic origami floats away, the researchers report today in Science Robotics. Primer can shed the walk-bot exoskeleton when exposed to another solvent. The researchers say that such “on-site morphing” could allow similar robots to do construction work in difficult environments, such as disaster zones or space, giving a whole new meaning to the phrase “transform and roll out!”