Shapeshifting edges could allow a new type of robot plane to be flown into storms to aid in search-and-rescue missions at sea, researchers report. A prototype of this small unmanned aerial vehicle is undergoing final trials in Cyprus, and the design is already attracting interest from governmental and civil rescue and surveillance organizations in Europe.
Severe weather poses a risk to the crews of helicopters and planes on maritime search-and-rescue missions. While robot planes have been proposed as a substitute for manned aircraft, "the main problem is that UAVs are small, light and affected by extreme weather," explained project coordinator Michael Amprikidis of the Cyprus-based engineering consultant firm GGD Technology Services.
The new robot plane, which the firm says will be relatively inexpensive, uses shapeshifting technology in its wings to improve flight stability. Amprikidis says that will enable the plane to fly even in bad weather. These novel elements consist of small flexing surfaces called trim tabs on the trailing edges of the hinged sections, or ailerons, on its wings. The trim tabs can vibrate, countering the destabilizing effects of heavy winds, and onboard sensors monitor their stability and provide constant feedback on how to continually adjust the tabs.
The craft is also equipped with state-of-the-art avionics such as autopilot, global positioning system receivers and, in case it can't access GPS, an inertial navigation system. From the command center, the robot plane's pilot can navigate wirelessly by looking through the onboard cameras.
The prototype was made with strong, lightweight materials such as Kevlar fiber and carbon fiber composites. It weighs 110 pounds (50 kilograms) with no fuel, and 595 to 605 pounds (270 to 275 kg) when fully fueled and equipped. It can take off from and alight at sea as well as land, and can stay aloft for 4.5 hours.
"The UAV was finished in June 2009 and the first flight was on a salt lake near Akrotiri [on Cyprus], selected for its very windy conditions," Amprikidis said.
Efforts had been made to ensure maximum stability for the plane even without the tabs — for instance, the UAV has a special aerodynamic profile optimized for high lift at low speeds.
"The aircraft flew first without the tabs and appeared very steady in crosswinds of up to 60 kilometers per hour [37 mph] — very severe conditions," Amprikidis said.
GGD is still improving the avionics. In addition to helping governments and civil rescue organizations, it could potentially help in scientific research, as it is capable of carrying up to 88 pounds (40 kg) of equipment and is much cheaper to operate than an ordinary plane.
"These results could lead even to big airline manufacturers using these methods for more fuel-efficient fleets and more comfortable rides for the passengers," Amprikidis told TechNewsDaily.