Aircraft Will Have Surveillance, Research Uses

Nine Dutch Aerospace Engineering students at the Delft University of Technology in the Netherlands, together with the Department of Experimental Zoology of Wageningen University have designed a tiny airplane fitted with shape- shifting wings, inspired by the common swift, one of nature's most efficient flyers.

Dubbed the RoboSwift, the aircraft will have unprecedented wing characteristics. The wing geometry as well as the wing surface area can be adjusted continuously to make it more maneuverable and efficient.

Resembling the common swift, RoboSwift will be able to go undetected while using its three micro cameras to perform surveillance on vehicles and people on the ground. It can be employed to observe swifts in flight, thus enabling new biological research, as well, according to the University.

The RoboSwift team presented the design to the yearly Design Synthesis symposium at TU Delft. The high-tech micro airplane is currently under construction and is expected to fly in January 2008. The student team will build three RoboSwifts to participate in the First American-Asian Micro Air Vehicle competition in India in March 2008.

The aircraft will have a wingspan of about 19 inches and weigh nearly three ounces. It will be able to follow a group of swifts up to 20 minutes and perform ground surveillance up to one hour thanks to its lithium-polymer batteries that power the electromotor, which drives the propeller. The propeller folds back during gliding to minimize air drag.

The morphing-wing design features are taken from the actual swift. The wings can be swept back in flight by folding feathers over each other thus changing the wing shape and reducing the wing surface area.

The students discovered that using only four feathers, much less than the bird uses, provides the wing with sufficient morphing capacity and is what makes actual production of the design feasible. Steering RoboSwift is done by asymmetrically morphing the wings. Sweeping one wing back further than the other creates a difference in lift on the wings that is used to roll and turn the micro plane in the air.

Although a few military aircraft -- such as the F-14 Tomcat and the English-German Tornado -- are equipped with so-called swing wings, none of these aircraft significantly reduces the surface area of the wing, thus missing out on the benefits made possible by morphing.

FMI: www.roboswift.nl, www.wageningenuniversiteit.nl/uk, www.tudelft.nl