Design and development of a high-altitude, in-flight-deployable micro-UAV

Abstract

A micro-UAV ([mu] UAV) system was developed to provide maximum endurance for a small atmospheric sensing payload. The system, composed of a ([mu] UAV) and protective case, folds and fits into a MJU-10/B flare cartridge (7.1" x 2.4" x 1.9") and is designed to be ejected in-flight from altitudes up to 30,000 ft at 300 G, to open and unfold in freefall, and to autonomous fly, sense, and transmit data for up to 45 minutes at maximum altitude. The[mu]UAV has a wingspan of 11.8", a length of 6.6", and a mass of 220 grams. Guided by first-principles, a series of design studies are conducted to maximize the airframe performance. The[mu]UAV is refined through computational analysis, prototyping, and a multi-phase testing program involving wind tunnel, structural shock, and deployment tests. A series of airfoils was developed for the low Reynolds numbers in which the wings operate (between 30,000 and 80,000) and for manufacturing considerations. Detailed design of aircraft components is presented with a discussion of small-scale composites manufacturing processes. Folding and control mechanisms were developed to actuate control surfaces on a swinging wing. The resulting design carefully balances low Reynolds number aerodynamic effects, small-scale composite structures, and manufacturing capabilities in a configuration that offers unprecedented endurance (for aircraft of this size and altitude) in a widely-compatible package with mission-reconfigurable payload.