Study of the application of smart materials on flexible wing UAV

Abstract

In recent years, UAV has been popular in the military and homeland security field for recon and surveillance purposes, with occasional search and rescue mission. However, conventional UAVs are expensive, heavy and bulky. Nonetheless, it requires more than one crew to operate it. With the demand of smaller, lighter, cheaper as well as instant launching single man operation UAV getting more, mini‐UAV was developed. However, the issues with mini‐UAVs is that their flight altitude is lower than those conventional UAVs. This causes the mini‐UAVs more vulnerable to severe weather condition. In order to overcome this, flexible wings made from layers of carbon fibers were invented. It is proved that flexible wing membrane is easier to maneuver in the windy weather thanks to the adaptive washout mechanism that came along with it. Furthermore, flexible wings can be wrapped around the mini‐UAV fuselage for storage and can be easily deployed. The purpose of this project is to improve the controllability of this flexible wing UAV due to the drawback on lack of aileron on the wings as it is not practical to have one. Flexible wing UAV depends solely on the control surfaces that is available at the empennage, be it a pair of ruddervators or elevons. Limited choices were given due to the constraints of the flexible wings. Torque rods are first to be eliminate as it will prevent the wings from folding during storage. Hence, smart materials became the first choice. With new actuation methods, new controls are needed.