Wing Integrated Solar Array Performance Study Using Photoluminescence

Abstract

Flight endurance and power are limiting factors affecting UAV applications today due to battery weight and capacity. Solar arrays integrated into the wing surface can provide additional power dependent on the sun, weight, wing area, and efficiency, and have demonstrated more than doubled flight times. With most wing surfaces having some degree of curvature and flexure during flight, stresses can be induced on the solar arrays. Photoluminescence is used to assess wing stresses by optically identifying crack propagation in the cells. NRL has built a variety of wings for UAVs from solar cell technologies. This paper intends to provide a demonstration of using this technique to study solar cell cracking through the array assembly process from wing integration to flight.