Measurements and performance prediction of an adaptive wing micro air vehicle

Abstract

The mission space requirements imposed on the design of micro air vehicles (MAVs) typically consist of several distinct flight segments that generally conflict: the transit phases of flight require high speeds, while the loiter/surveillance phase requires lower flight velocities. Maximum efficiency must be sought in order to prolong battery life and aircraft endurance. The adaptive wing MAV developed at the University of Arizona features a thin, deformable flying wing with an efficient rudder-elevator control system. The wing camber is varied to accommodate different flight speeds while maintaining a constant total lift at a relatively low angle of attack. A new airfoil was developed from the Selig 5010 that features a small negative pitching moment for pitch stability. Wind tunnel tests were performed and stall angles and best lift-to-drag ratios were analyzed from the data. The wind tunnel data was used in a performance analysis in order to determine the flight speeds and throttle settings for maximum endurance at each camber, as well as the MAV's theoretical minimum and maximum flight speeds. The effectiveness of camber change on flight speed and endurance was examined with promising results; flight speed could be reduced by 25% by increasing the camber from 3 to 9% without any increase in power consumption.

Effect of Camber on the Aerodynamics of Adaptive-Wing Micro Air Vehicles

“…1) and represents an increased reflex version of the airfoil section used in the previous study. 12 The increased reflex was added after numerous test flights showed that MAVs utilizing the preceding airfoil section needed excessive up-elevator deflections to maintain steady, level flight, resulting in decreased flight times. 14 The facility used to perform this series of tests is known as the Low Speed Wind Tunnel and is located in the Department of Aerospace and Mechanical Engineering at the University of Arizona.…”

“…11,12 In Ref. 11 the concept of an adaptive-wing micro air vehicle (with an emphasis on variable camber) was introduced, and a flying test model was developed that was capable of camber change from 0% (flat plate) to approximately 9%.…”

Elements of Aerodynamics, Propulsion, and Design

“…Students and faculty at the University of Arizona began the development of a number of MAVs in 2000 [75] and [76], and they began entering the competitions in 2001. At the Sixth International MAV competition in 2002 at Brigham Young University in Provo, Utah, they introduced a variable camber wing and received the Ingenuity Design award.…”

Development of Micro Air Vehicles with in-Flight Adaptive Wing

“…This new airfoil was designated as S5010-TOP24C-REF [8]. To compensate for this, the airfoil was modified so that the chordwise position of maximum camber was moved to 24% of the chord instead of the 29% found on the standard S5010 top surface.…”

“…Past work at the University of Arizona has resulted in some interesting findings regarding the benefits of micro air vehicles with adaptive wings [7] and [8]. The concept of an adaptive wing micro air vehicle was introduced, and a flying test model was developed that was capable of camber change from 3 to 9%.…”