Researchers from MIT CSAIL and Harvard’s Wyss have implemented the art of Origami in Soft Robotics to provide a strong and flexible skeleton to the structure. Details regarding the invention were published in Proceedings of the National Academy of Sciences recently and is another milestone for the field.

About soft robots

The defining qualities of these robots being safety, flexibility and adaptability, they have a wide variety of applications in medicine and industry practices. Soft robots are structures which rely on a system of hydrostatic pressure differentials to operate. They can be likened to flexible bags or cases which possess a high degree of compressibility. Plant cells have a material called cytoplasm within them and regulating the pressure differentials between this fluid and the surrounding liquid enables them to change their shape.

Similarly, in soft robotics, a hydrostatic pressure is developed using an electric motor to change the fluid pressure inside the bag to change its stiffness. The structures can be used independently or with others to create mechanisms for suitable operation. Until recently they have been successful in including an aspect of flexibility and adaptability to robotics but have been held back by their lack of strength.

Image: Qruis

Art in science

This has changed with the implementation of Origami in the skeleton for the structure. The 17th-century art-form, where structures are folded in specific patterns to deliver easy storage and strength, has found multiple takers in the scientific community. They have been used in telescopes and solar panel deployment mechanisms in spacecraft with much success. In soft-robotics, an origami-inspired skeleton provides the necessary strength and controls the application of the structure.

Superpowers

The outer covering of each unit can be likened to muscles in terms of the states of tension and compression it reproduces. Each ‘muscle’ can be contracted to 10 per cent of its original size and can generate a pressure up to six times that shown by a human. Weighing just 2.6 grams, it can lift up to three kilograms. The material is made of Poly Vinyl Alcohol (PVA) and at less than one dollar, can be 3D printed in 10 minutes. The material is bio-degradable as well which holds good for the environment.

A senior member of the team and Director of CSAIL, Daniela Rus said, “We were very surprised by how strong the muscles were. We expected they’d have a higher maximum functional weight than ordinary robots, but we didn’t expect a 1000 fold increase. It’s like giving these robots superpowers“.

An outreach

The structure is limited by the orientation of the skeleton which means it can have only a single mode of operation and a fixed movement pattern. Regardless, a combination of several of these units can be implemented in operation. The team responsible have run a number of tests to determine its viability and have successfully handled small flowers and heavy tires using the robots.

Until now the handling of different kinds of objects possessing different shapes was addressed using Artificial Intelligence. The flexible structure used in soft robots solves this problem and behaves like a human hand with its soft surface. The system also gets rid of the control systems needed to operate a robotic joint as it works similar to a switch with an ON/OFF function and hydraulics are the driving force. The robots have a lot of use invasive surgery and as a form of exoskeleton for manual labour.

In her own image