Robots that can wiggle, fold and transform
Robots are occasionally called in to access places considered too difficult to reach by rescue workers, but most rescue robots used today are big and rigid, and their ability to navigate tight spaces is limited.
To solve that problem, a research team at Stanford University recently developed a “soft robot.” Made of polyethylene, this robot resembles a transparent tube. It moves forward toward the target by extending itself like a vine with a maximum length of 72 meters (236 feet). When fully inflated, it is able to lift objects that weigh up to 100 kilograms (220 pounds).
“The applications we’re focusing on are those where the robot moves through a difficult environment, where the features are unpredictable and there are unknown spaces,” said Laura Blumenschein, a graduate student and co-author of the paper that introduced the invention.
Another material that can be used in soft robots is carbon. Conventional robots are made of metal-based material that is solid and strong. The downside is that they can be heavy and possibly harmful to people.
On the contrary, soft robots use more flexible materials that are relatively safer. These materials include silicon and rubber, and scientists believe they can play a role in areas where solid robots cannot help. Market research firms like Gartner and IDC as well as Forbes Magazine have cited soft robots as a technology to watch in the near future.
A soft robot developed by a team at the Massachusetts Institute of Technology is capable of folding itself like origami paper. It can also be swallowed in the form of a capsule.
The robot folds and unfolds as it moves to its destination, where it can be externally controlled and perform tasks like removing foreign objects from the body, patching wounds and delivering medicine. Outside of medicine, the robot can also be used to fix small cracks in construction and machinery.
At Harvard University, Prof. George Whitesides invented a soft robot that resembles a starfish. Not only does it have a soft surface, but it also lacks hard internal parts. Its finger-like claws are able to pick up and put down fragile objects such as eggs.
The field of soft robotics research emerged in 2007, when Prof. Cecilia Laschi of the Sant’Anna School of Advanced Studies in Italy introduced a robot that moved like a mollusk. The internal structure was based on springs, and the surface was made of silicone.
At the time, the initial reaction from roboticists was far from excitement. The general consensus was that robots had to have a hard body and move mechanically.
But now, there is a dedicated journal on soft robots, and the number of papers tackling the concept is on the rise.
Octobot, made by a team of Harvard researchers, can move on its own without using any electricity. Instead of batteries, it operates on a small amount of oxygenated water. The substance reacts with a platinum catalyst inside the device to generate oxygen gas, the robot’s main fuel.
In Switzerland, the Ecole Polytechnique Federale de Lausanne created a soft actuator, a type of motor essential in the movement and control of a machine. This invention, made of gelatin and glycerol, can hold air or liquid inside its body and move using chemical reactions. The robot can potentially deliver medicine into the body and perform surgeries.
There are disadvantages to soft robots. They are more prone to transformation and wear and tear compared to solid-surface robots. Researchers from the Universite libre de Bruxelles in Belgium found a solution to this problem by developing a soft robot that naturally heals itself within a day when heated.
Soft robotics is on the rise in Korea as well. “Metal robots can cause harm to people, and they give a more uncomfortable impression,” said Seo Tae-won, a professor of mechanical engineering at Yeungnam University. “On the other hand, soft robots feel friendlier and are actually safer. Many research projects are underway to design soft robots for use in industry and medicine.”
BY SOHN HAE-YONG, SONG KYOUNG-SON [firstname.lastname@example.org]