The drone inspired by a dragonfly

News article written by John Garth.

Ever since Leonardo da Vinci, we have dreamed of mimicking natural flight. Neither fixed-wing nor rotor-driven aircraft quite fit the bill — but now an Oxford University spinout is making it a reality, inspired by the flight of the dragonfly. The drone being developed by Oxford University spinout Animal Dynamics is the stuff of science fiction, but its military potential is equalled by its humanitarian possibilities.

Skeeter will have four independently flapping wings, a camera and microphone, and will fly at up to 45 kph. Yet it will be no more than 12cm long and 30g in weight. Adrian Thomas, Professor of Biomechanics in the Department of Zoology, says Skeeter will be more manoeuvrable and able to fly further and more cheaply than any comparable vehicle. Its wings are extremely light and require far less energy than rotors, are more robust, and handle buffeting winds far better.

Helicopters have fundamental problems. To carry heavy loads requires very fast rotation, which eats up energy and limits their endurance.

Dragonflies can flap, twist and curve each of their four wings independently. If a dragonfly loses a wing, it can cope simply by increasing the amplitude of its flapping. ‘If you take one rotor off a quad copter, it falls out of the sky, but a dragonfly can cope with that rather well.’ Skeeter will share these capabilities.

Skeeter will be ideally suited  for flying in ‘urban canyons’ — that’s just military parlance for streets, laughs Thomas. They also mean it will be able to explore disaster areas. Whether it’s covert surveillance in enemy territory or locating survivors in earthquake zones, Skeeter will scope out what’s going on.

Five years ago Skeeter would have been impossible. So what’s changed? ‘It’s all because of mobile phones,’ says Thomas. Big technological strides have been driven by mass demand for pocketable phones with cameras, long-lasting lightweight batteries and inertial measurement units – the components that tell phones which way up their screen displays should be.

The concept design has been funded by the MoD’s Defence Science and Technology Laboratory, known as Dstl. Skeeter has been introduced to Defence Secretary Michael Fallon (above) and has now won further Dstl funding, plus support from the MoD’s newly launched £800 million Innovation and Research Insights Unit, or Iris. The Ministry of Defence says it could have ‘a huge impact on intelligence-gathering in future operations in complex urban environments.’

One goal has been to build the drones down to a price, so they can be thrown away, ‘so you can sacrifice them by flying them into hazardous zones when you wouldn’t want to put a person in there.’

The flapping-wing principle makes for a much safer device, too. ‘A conventional quad-copter can leave you with horrible injuries — it’s essentially a flying lawnmower.’

These elements add up to something with real humanitarian potential, argues Thomas. Talks with humanitarian relief organisations are driving the spinout’s work on other drones that could deliver a payload of 10kg and potentially even larger devices.

The inspiration ultimately comes from his work in the Zoology Department when he ran the Animal Flight Group. ‘We would not be building these things if I hadn’t been able to do absolutely blue-skies research about dragonfly flight funded by the research councils.’

Animal Dynamics’s work is not confined to the air. Also in the works are water vehicles propelled by whale-like tales, and a legged off-road wheelchair that can negotiate stairs.

But the phrase ‘the sky’s the limit’ has never seemed more apt. Irrepressibly enthusiastic, and a national paragliding champion four times over, Adrian Thomas also talks of Animal Dynamics’ work on remote-controlled paragliders that can be launched from the back of a car to carry a ton of equipment or supplies across inhospitable environments. Costing just a few thousands pounds, they too could be sacrificed if need be.

Similar drones modelled on animal flight could save lives in disasters like the April 1915 Nepal earthquake, says Professor Thomas

‘We’ve got these devices that can cope with the problems they had recently in the  Himalayan earthquake, when they couldn’t deliver supplies to people they could see on the other side of the valley,’ he said. ‘And the whole thing is scaleable. We can produce everything in between 30g vehicles and things that can deliver a tonne of supplies.’

‘If anybody says, “Who’s ever heard of anything with wings delivering anything?” — well, pigeons are always delivering things, and more significantly storks are always delivering nine-pound packages!’

All these ideas should benefit from the technologies being developed for Skeeter. Animal Dynamics aims to have a fully operational prototype of the dragonfly drone in the air this year.

‘The MoD are aware that there’s a synergy of other things being produced at the same time. And for us it’s great. We make little surveillance drones for the Mod, and we make devices for delivering medical packages to people who are otherwise inaccessible.’

Beneath this there is another motivation — the pure motivation of craft, engineering, and design. ‘The convergent solutions that biology has evolved all end up being the most beautiful things to look at,’ finishes Thomas. ‘When you watch dragonflies fly they are the most beautiful things. The aim fundamentally is to make beautiful things inspired by nature.’

Article first published here: http://www.oxfordtoday.ox.ac.uk/interviews/drone-inspired-dragonfly