Laser beam lift-off for wireless winged robot
Image credit: Mark Stone/University of Washington
Engineers at the University of Washington have developed the world’s smallest wireless flying machine, called RoboFly, which is powered using an invisible laser beam.
Small, cheap robots inspired by flies and other flying insects could have roles in defence, surveillance and agriculture, surveying large or difficult-to-reach areas while causing minimal disruption. These insect-inspired robots are too small to use propellers, as drones do, so instead they lift themselves into the air by flapping tiny wings.
At present, these insect-inspired robots require tethering; the bulk and weight of their batteries and other electronics required to power their energy-intensive wings prevents them from taking off.
For the first time, engineers have created a winged robot – dubbed the ‘RoboFly’ – capable of lifting itself into the air wirelessly. Instead of carrying a battery, RoboFly is powered using a laser beam. A small photovoltaic cell mounted on top of the robot is used to convert energy from the narrowly-directed, invisible beam. When amplified with a circuit, this provides just enough electricity to flap its wings and fly.
“Before now, the concept of wireless insect-sized flying robots was science fiction. Would we ever be able to make them work without needing a wire?” said co-author Professor Sawyer Fuller, of the University of Washington’s Department of Mechanical Engineering. “Our new wireless RoboFly shows they’re much closer to real life.”
Previously, Fuller and his colleagues worked on RoboBee, an insect-inspired robot capable of flying while tethered to a power source, as well as diving and swimming underwater using its wings.
In order to enable RoboFly to overcome the force of gravity and take flight, the engineers had to ensure that it was extremely light; the mostly hollow robot weighs little more than a toothpick. Among its small number of vital components is a microcontroller, which gives the robot control over its movement, which is inspired by that of real winged insects.
“The microcontroller acts like a real fly’s brain, telling wing muscles when to fire,” said co-author Vikram Iver, a PhD student in electrical engineering. “On RoboFly, it tells the wings things like ‘flap hard now’ or ‘don’t flap’.”
At present, RoboFly is only capable taking off and landing, as it needs to remain within line-of-sight of the static laser which provides its power. Next, the Washington engineers hope to give RoboFly greater movement by steering the laser around a room.
Future iterations of RoboFly could be powered by tiny, lightweight batteries or even harvest small amounts of energy from radio frequency signals in its environment. RoboFly’s creators suggest that these more sophisticated RoboFlies could also have abilities to navigate autonomously and complete simple tasks, such as detecting gas leaks or measuring carbon dioxide concentrations by “looking for smelly things”, just as real flies do.