May 23, 2014
Multi-Research Demonstrates The Future Of Animal-Inspired Drones
Lawrence LeBlond for redOrbit.com - Your Universe Online
Drone technology is still in its relative infancy, despite the concept dating back to the mid-1800s when Austrians first sent off unmanned, bomb-filled balloons as a way of attacking Venice remotely.
And while the US military has dabbled with drone technology for decades, the future of this UAV-technology is about to take off to new heights.
New research is looking to develop solutions that some of the most common problems drones could face, such as navigating urban environments and performing novel tasks. These solutions could come based on the work of 14 distinguished research teams, who are investigating how mechanisms adopted by birds, bats, insects and other creatures can be used to solve real-world problems for the next generation of drones.
This innovative work has been published in a special edition of IOP Publishing’s journal Bioinspiration and Biomimetrics.
Modern drone technology is already being used in search and rescue operations. After the deadly earthquake and ensuing tsunami in Japan in 2011, difficult to reach areas were investigated using small drones. A team of Hungarian researchers believe the efforts employed during that tragedy could be improved if robots are developed to work in tandem, using a sophisticated algorithm that allows a number of drones to fly together like a flock of birds.
The team demonstrated the effectiveness of this algorithm in a new study, using it to direct the movements of nine individual quadcopters while they followed behind in a moving car.
Another study team based out of Harvard University, took another route, focusing on drones that can maneuver through tight spaces, rather than working together to cover vast expanses of land. The Harvard researchers developed a millimeter-sized drone – about the size of a penny – that could take off, hover in the air for sustained periods of time, and land with simple, fly-like maneuverability.
The team said their drones could one day be used “in assisted agriculture pollination and reconnaissance, and could aid future studies of insect flight.”
Navigating tight spaces and working together in large, open areas are but a few problems researchers are working on for future drones. Once these high-tech vehicles are deployed, they will likely be faced with the tricky task of maneuvering through dangerous elements, such as extreme heat, freezing cold, torrential rain storms, high wind and lightning.
The most extreme of these challenges is most likely wind, which has given researchers from the University of North Carolina at Chapel Hill, University of California and The Johns Hopkins University the idea of studying one creature that is a master of flying in windy situations: the hawk moth.
The team had hawk moths fly through a number of different whirlwind conditions in a vortex chamber, examining the mechanisms that the hawk employs to successfully regain flight control.
Another challenge for drone technology is finding a way to reduce the amount of power that is required to operate drones. A team from Université de Sherbrooke and Stanford University took on this challenge by creating a “jumpglider.”
The jumpglider was inspired by vertebrates like the flying squirrel, the flying fish and the flying snake, which all employ the aerodynamics of their bodies to extend the distance to which they can jump and glide. Based on the observations of these creatures, the team’s jumpglider combined an airplane-shaped body with a spring-based mechanical foot that propels the robot into the air.
The jumpglider may one day be used for search and rescue efforts and can operate at low power, offering a significant advantage over land-based robots that must navigate around obstacles and over rough terrain.
“Flying animals can be found everywhere in our cities. From scavenging pigeons to alcohol-sniffing fruit flies that make precision landings on our wine glasses, these animals have quickly learnt how to control their flight through urban environments to exploit our resources,” wrote special issue Guest Editor Dr David Lentink of Stanford University.
Lentink, who is an aerial robotics expert, said this sort of bio-inspiration is pushing drone technology forward because evolution has solved challenges that drone engineers are just beginning to address.
"There is no drone that can avoid a wind turbine," he told BBC News. "And it is very difficult for drones to fly in urban environments," where there are vast numbers of obstacles to navigate, and turbulent airflow to cope with. Even the humble pigeon "flies where drones still can't,” he said.
Another study has developed some technology that will help drones navigate around dangerous objects, drawing inspiration from insects that have the “amazing capability of flight in clutter,” said Lentink.
Researchers from the University of Maryland engineered sensors for their experimental drone based on the eyes of insects. These “eyes” are actually miniature cameras connected to an on-board computer that is programmed to steer clear of surrounding objects.
Another team from Brown University developed an eerily realistic robotic bat wing that demonstrates remarkable range of movement and flexibility. The team drew their inspiration from the thin wing membrane that is unique to bats.
Membrane-based bat wings are of particular interest to drone engineers, because they are so tolerant of impact, noted Prof Kenny Breuer, lead researcher of the bat wing study.
"They deform instead of breaking," explained Prof Lentink to BBC. "They are also adapting better to the airflow because they're so flexible."
Some of the drone technology being developed will be of great benefit to humanity.
Researchers at Imperial College London are working on robots that can “perch” in trees and elsewhere, enabling drones to become “mobile networks of sensors.”
"I'm very excited about the future of this field," lead researcher Dr Mirko Kovac told the BBC. "There are a lot of tasks that we can do with flying robots, such as sensing pollution, observing and protecting wildlife, or we could use them for search and rescue operations after tsunamis."
"It's important that the applications benefit humanity,” he said. "We must take the responsibility to built [sic] robots that are beneficial to society and used in an ethical and positive way."
While these and other research teams have come a long way in the development of innovative technologies for the future of drones, one expert in animal flight said that engineers still have a much longer road ahead before they truly achieve the feats that animals were capable of.
"The depth of our understanding of the biological systems greatly exceeds the depth of our ability to exploit the underlying principles in engineered systems," University of Oxford’s Prof Graham Taylor explained to BBC News. "So whilst the promise is great, it remains early days for the field."
Still, the technology is exciting and novel for many of these research teams.
“This special issue provides a unique integration between biological studies of animals and bio-inspired engineering solutions. Each of the 14 papers presented in this special issue offer a unique perspective on bio-mimetic flight, providing insights and solutions to the take-off, obstacle avoidance, in-flight grasping, swarming, and landing capabilities that urban drones need to succeed,” concluded Lentink.
Image 2 (below): Flocking drones could be used in search and rescue operations. Credit: ELTE Department of Biological Physics