How to Fly Forever: A Parametric Design Study of LALE Solar UAV’s

Recent advances to the performance of photovoltaic cells and batteries has made it practical to field solar-powered unmanned aerial vehicles (UAV) with potentially unlimited endurance. We present a design study of perpetual endurance low-altitude solar-powered UAV’s with the goal of identifying the ideal future configuration for flight test vehicle 3 (FTV3) of our CREATeV project towards the objective of achieving robust year-round endurance at a low cost. We present a low cost flight performance model and validate its predictions against detailed theoretical analyses and our own flight test data. We integrate the expected flight power and expected solar income across a range of dates and weather conditions to obtain our objective function: the energetic margin on our capability for perpetual flight. We analyze the performance of a variety of configurations derived from the existing CREATeV FTV2 by modifying the wing planform profile, section profile, structural definition, solar area, and battery capacity, and characterize the trends of this design space. We implement a framework for multidisciplinary optimization to generate candidate configurations, and combine the predicted performance in our objective function with practical manufacturing considerations to select and present a design proposal for FTV3.