Design and Testing of a Dual Tilt-Wing Micro Air Vehicle

The objective of the present work is to develop a fully functional tilt wing micro air vehicle (MAV) that can be used as a baseline platform for future optimization and autonomous operations. The design, integration, control methodology and performance of a 100 gram tilt-wing MAV in hover is discussed. The vehicle consisted of a pair of 5 inch three-bladed counter-rotating propellers mounted at the tips of 3.5"x1"carbon fiber wings. A pair of high torque-weight servos mounted in the center of the fuselage is used to rotate the wings. Experiments showed that in the tilt wing configuration the download on the wings due to the propwash is about 4% of the propeller thrust as opposed to 27% for the tilt rotor. Hover control was achieved by a careful selection of servo rotation and motor RPM variation using a 1.5 gram onboard sensor platform. The performance of the propellers, wings and fuselage parasitic drag were then measured individually in the forward flight configuration in a series of wind tunnel tests to determine forward flight capability. Optimum wing root pitch angles were found to be 90-120 that produced maximum L/D around 5-7. The minimum speed required to produce sufficient fixed wing lift was found to be 6.5 m/s. Based on wind tunnel data, the tilt wing MAV is fully capable of forward flight at speeds of at least 8 m/s.