A team of researchers from the University of South Australia (UniSA) is designing a dragonfly-inspired drone in a bid to create a new type of UAV that matches the insect's agile hovering capabilities, as detailed in their study published in Drones.
Led by UniSA Professor of Sensor Systems, Javaan Chahl, a team of PhD students worked remotely on the project, with some even using spare rooms at home to test prototype flapping wing parts.
In a press statement, Professor Chahl called the dragonfly the "apex insect flyer." He said "dragonflies are supremely efficient in all areas of flying. They need to be. After emerging from underwater until their death (up to six months), male dragonflies are involved in perpetual, dangerous combat against male rivals."
"Mating requires an aerial pursuit of females and they are constantly avoiding predators. Their flying abilities have evolved over millions of years to ensure they survive," he continued.
Dragonflies turn quickly at high speeds and can rise into the air carrying more than three times their own body weight. They also chase and capture their prey with a 95 percent success rate, making them one of nature's most efficient predators.
A flying machine developed over 300 million years
In order to make their prototype, the researchers modeled the body shape and aerodynamic properties of the dragonfly in a bid to understand how the insect has become so efficient at flying over the course of 300 million years of evolution.
The team reconstructed 3D images of the wings, and studied the wing geometry of 75 different dragonfly species via a newly-developed optical technique.
"Dragonfly wings are long, light, and rigid with a high lift-to-drag ratio which gives them superior aerodynamic performance," Chahl said.
"The [dragonfly's] long abdomen, which makes up about 35 percent of their body weight, has evolved to serve many purposes. It houses the digestive tract, is involved in reproduction, and helps with balance, stability, and maneuverability. The abdomen plays a crucial role in their flying ability."
We're likely a long way from seeing dragonfly-inspired drones hit the market. Though ornithopters — aircraft with flapping wings — could be highly efficient in theory, we are yet to see a model that could suitably challenge today's rotor-enabled UAVs and helicopters for hover efficiency.
Last year, a National University of Singapore-led project designed a drone with flapping wings that could hover and glide. Meanwhile, last month, a team from Russia revealed the first controlled flight of their dragonfly-inspired ornithopter.
Though winged drones are still very much in early development, the UniSA team believes that more research and development into a dragonfly-like drone could allow for more efficient payload delivery as well as long surveillance missions executed with the aid of its efficient flight technique.