‘Virtual top hats’ allow swarm of robots to fly in tight formation
Researchers from Georgia Institute of Technology have created a swarm of free-flying robots which avoid colliding or undercutting each other, along with an autonomous blimp which can recognise facial expressions and hand gestures.
The five quadcopters – helicopters with four rotors – can fly in tight formation, changing their behaviour mid-flight based on commands.
The field of swarm robotics is based heavily on the study of insects and other organisms which live in colonies. A swarm of robots consists of simple robots which interact to give rise to useful collective behaviour. Swarm robotics could be useful in sensing tasks, such as in foraging, or to survey areas after disasters in search of survivors. More controversially, swarm robotics could have military applications; US naval forces have already tested a swarm of autonomous boats which attack of their own accord.
“Our skies will become more congested with autonomous machines, whether they’re used for deliveries, agriculture or search and rescue,” said Professor Egerstedt, director of Georgia Tech’s Institute for Robotics and Intelligent Machines. “It’s not possible for one person to control dozens or hundreds of robots at a time. That’s why we need machines to figure it out themselves.”
Flying swarms of robots, however, suffer from frequent collisions and undercutting. When a machine flies below another, it will struggle to stay aloft in the turbulent air and may be blasted to the ground.
“Ground robots have had built-in safety ‘bubbles’ around them for a long time to avoid crashing,” said Professor Magnus Egerstedt, director of Georgia Tech’s Institute for Robotics and Intelligent Machines.
“Our quadcopters must also include a cylindrical ‘do not touch’ area to avoid messing up the airflow for each other. They’re basically wearing virtual top hats.”
While the robots avoid flying in the two-foot space below neighbouring machines, they can fly in tight formation.
The Georgia Tech researchers will present their flying swarm of robots at the IEEE International Conference on Robotics and Automation in Singapore in June, along with another original robot: the world’s smallest autonomous blimp.
The blimp is made up of a 3D-printed gondola frame, attached to a 46cm or 91cm circular balloon, much like a helium-filled party balloon. Unlike zeppelin-shaped blimps, they are tricky to steer with controllers, but able to quickly change direction.
It carries sensors and a mini camera to detect gestures and faces; this allows its operator to direct it using hand gestures. All the while, the blimp gathers data about its operator, learning to identify facial expressions.
According to Professor Fumin Zhang, who is leading the project, the goal is to better understand how people interact with flying robots.
“Flying a regular drone close to people presents a host of issues,” he said. “But people are much more likely to approach and interact with a slow-moving blimp that looks like a toy.”
Professor Zhang believes that blimps could have a significant role to play in modern civilian life, but first roboticists need to determine exactly what people expect from flying robots, and how they will interact with them.
“Imagine a blimp greeting you at the front of the hardware store, ready to offer assistance,” he said. “People are good at reading people’s faces and sensing if they need help or not. Robots could do the same. And if you needed help, the blimp could ask, then lead you to the correct aisle, flying above the crowds and out of the way.”