Engineering news
Researchers from the Wyss Institute for Biologically Inspired Engineering and the John A. Paulson School of Engineering and Applied Sciences at Harvard University created the devices, which were inspired by the 1500-year-old Japanese folding technique. The robots are capable of complex movement and could have many potential uses, the team said.
The robots are flat and thin plastic tetrahedrons, with three outer triangles connected to one central triangle with a small electrical circuit. The triangles move independently, contracting or relaxing like human muscles to allow the devices to move.
“Like origami, one of the main points of our design is simplicity,” said professor Je-sung Koh. “This system requires only basic, passive electronic components on the robot to deliver an electric current - the structure of the robot itself takes care of the rest.”
Research teams at Harvard and other organisations like Nasa and MIT have investigated folding robots for several years, with possible uses including medical inspections and searching for disaster survivors. However, the Wyss and Harvard team say their robots are more functional and less bulky because they have no battery or external power source.
Instead, they are controlled by electromagnetic power transmission, the same technology in wireless charging pads for mobile devices. The magnetic field created heats coils of a type of metal called shape-memory alloy on the robots’ hinges, expanding or contracting and moving the flaps. Each coil reacts to a specific electromagnetic frequency, allowing the team to move each part of the robot independently and therefore make complex movements.
“When people make micro-robots, the question is always asked, 'How can you put a battery on a robot that small?',” said Rob Wood from the Wyss Institute. ‘This technology gives a great answer to that question by turning it on its head: you don't need to put a battery on it, you can power it in a different way.”
The team built several robots of different sizes, from small coins to hand-sized. Large robots could be installed in homes to enable wireless, battery-free communication between multiple “smart” objects, the team said.
Smaller devices could be used as medical robots, replacing uncomfortable endoscopes for patients. People would swallow the robots, which could move around and perform simple tasks like holding tissue or filming.
“Medical devices today are commonly limited by the size of the batteries that power them, whereas these remotely powered origami robots can break through that size barrier and potentially offer entirely new, minimally invasive approaches for medicine and surgery in the future,” said bioengineer and Wyss founding director Donal Ingber.
The research was published in Science Robotics.