A Flapping Drone Mimics Aerobatic Maneuvers of the Swift, One of the World's Fastest Birds

The surveillance applications are clear, but novel applications include pollination of indoor vertical farms without damaging dense vegetation, unlike the rotary-propelled quadcopters whose blades risk shredding crops.

Because of their stability in strong winds, the ornithopter drone could also be used to chase birds away from airports, reducing the risk of them getting sucked into jet engines.

“The optimised ornithopter acts as a kind of scarecrow, greatly saving on labour costs for pest control companies and airport operators,” Dr Chin says.

There are currently no commercialised ornithopters being used for surveillance, but this could change with the latest breakthrough, researchers claim.

By improving the design so ornithopters can now produce enough thrust to hover and to carry a camera and accompanying electronics, the flapping wing drone could be used for crowd and traffic monitoring, information gathering and surveying forests and wildlife.

The light weight and the slow beating wings of the ornithopter poses less danger to the public than quadcopter drones in the event of a crash and given sufficient thrust and power banks it could be modified to carry different payloads depending on what is required.

One area that requires more research is how birds will react to a mechanical flying object resembling them in size and shape. Small, domesticated birds are easily scared by drones but large flocks and much bigger birds have been known to attack ornithopters.

And while the bio-inspired breakthrough is impressive, we are a long way from replicating biological flight, Dr Chin says.

“Although ornithopters are the closest to biological flight with their flapping wing propulsion, birds and insects have multiple sets of muscles which enable them to fly incredibly fast, fold their wings, twist, open feather slots and save energy.

“Their wing agility allows them to turn their body in mid-air while still flapping at different speeds and angles.

“Common swifts can cruise at a maximum speed of 31 metres a second, equivalent to 112 kilometres per hour or 90 miles per hour.

“At most, I would say we are replicating 10 per cent of biological flight,” he says.

“Efficient flapping wing drone arrests high speed flight using post-stall soaring” is published in Science Robotics. 

The project was a culmination of PhD work done by Dr Yao-Wei Chin at Nanyang Technological University under the guidance of Associate Professor Gih-Keong Lau (now with National Chiao Tung University, Taiwan), and an international collaboration comprising Professor Boo Cheong Khoo (National University of Singapore), Professor Javaan Chahl and Dr Jia Ming Kok (University of South Australia and Defence Science and Technology Group, Australia), Dr Yong-Qiang Zhu (Qingdao University of Technology, China) and Dr Woei Leong Chan (National University of Singapore).