Harvard's bug-sized robot uses electric feet to explore tiny spaces upside-down

HAMR-E robot

Photo credit: Wyss Institute at Harvard University

Researchers at Harvard University have created a tiny walking robot with electro-adhesive feet that's capable of wandering around freely inside tiny spaces – even upside-down, provided the surface can conduct electricity.

The Harvard Ambulatory Micro-Robot with Electroadhesion  (HAMR-E), which was developed in response to a challenge from Rolls-Royce, is able pad around deep inside spaces too small for humans to each. It's hoped that the bot will eventually be able to carry tools and cameras, allowing engineers to inspect and repair complex machines (like Rolls-Royce's jet engines) without disassembling them. 

Sticky business

The robot's 'sticky' foot-pads consist of a polyimide-insulated copper electrode, which enables generation of electrostatic forces between the feet and the conductive surface. The pads can be engaged and released by switching the electric field on and off (much like an electromagnet).

It also has a special gait, which enables it to walk while inverted. Three of its feet remain attached to the surface to keep it from sliding off the surface, while the fourth swings forward and re-attaches further along. 

This unique way of walking causes the legs to rotate, so the researchers created special origami-inspired ankle joints to compensate. Layers of tough fibreglass and polyimide are folded into a structure that lets the ankles rotate freely and adapt to the surface as the little bot wanders about.

Baby steps

HAMR-E has great potential, and the researchers are now exploring ways to detect and compensate for detached foot pads, so it doesn't drop off if it loses its footing (nobody wants to hunt inside a jet engine for a tiny broken robot), and make it walk on non-conductive surfaces.

Video credit: Wyss Institute at Harvard University

"This iteration of HAMR-E is the first and most convincing step towards showing that this approach to a centimeter-scale climbing robot is possible, and that such robots could in the future be used to explore any sort of infrastructure, including buildings, pipes, engines, generators, and more,” said Robert Wood PhD, co-author of a report on the project in Science Robotics.

“While academic scientists are very good at coming up with fundamental questions to explore in the lab, sometimes collaborations with industrial scientists who understand real-world problems are required to develop innovative technologies that can be translated into useful products."

Cat Ellis

Cat is the editor of TechRadar's sister site Advnture. She’s a UK Athletics qualified run leader, and in her spare time enjoys nothing more than lacing up her shoes and hitting the roads and trails (the muddier, the better)