A design framework for realizing multifunctional wings for flapping wing air vehicles using solar cells

Abstract

Long flight durations are highly desirable to expand mission capabilities for unmanned air systems and autonomous applications in particular. Flapping wing aerial vehicles are unmanned air system platforms offering several performance advantages over fixed wing and rotorcraft platforms, but are unable to reach comparable flight times when powered by batteries. One solution to this problem has been to integrate energy harvesting technologies in components, such as wings. To this end, a framework for designing flapping wing aerial vehicle using multifunctional wings using solar cells is described. This framework consists of: (1) modeling solar energy harvesting while flying, (2) determining the number of solar cells that meet flight power requirements, and (3) determining appropriate locations to accommodate the desired number of solar cells. A system model for flapping flight was also developed to predict payload capacity for carrying batteries to provide energy only for power spikes and to enable time-to-land safely in an area where batteries can recharge when the sun sets. The design framework was applied to a case study using flexible high-efficiency (>24%) solar cells on a flapping wing aerial vehicle platform, known as Robo Raven IIIv5, with the caveat that a powertrain with 81% efficiency is used in place of the current servos. A key finding was the fraction of solar flux incident on the wings during flapping was 0.63 at the lowest solar altitude. Using a 1.25 safety factor, the lowest value for the purposes of design will be 0.51. Wind tunnel measurements and aerodynamic modeling of the platform determined integrating solar cells in the wings resulted in a loss of thrust and greater drag, but the resulting payload capacity was unaffected because of a higher lift coefficient. A time-to-land of 2500 s was predicted, and the flight capability of the platform was validated in a netted test facility.

Issues of Optimizing the Use of Solar Panels for Uav Power Supply

“…1. Усовершенствование батарей [2][3][4]; 2. Увеличение эффективности полета с использованием свойств атмосферных процессов [5][6][7], физическую основу которых составляют различные перемещения теплых воздушных потоков.…”

Exfoliated Fluorographene Quantum Dots as Outstanding Passivants for Improved Flexible Perovskite Solar Cells

“…Tremendous efforts have been devoted to develop high-efficiency flexible solar cells in recent years to meet the energy demands of various moving objects, wearable devices, and buildings with curved surfaces. − Of the flexible thin-film solar cells, flexible lead halide perovskite solar cells (PSCs) have gained worldwide attention owing to their low cost and high power conversion efficiencies (PCEs). − Though the state-of-art PCE of the flexible single-junction PSC has been reported as 20.01%, further enhancement is required as the champion PCE of flexible CuIn 1– x Ga x Se 2 solar cells has already exceeded 20%. , Defects within the perovskite absorber play a crucial role in determining the PCEs of PSCs, especially those of the flexible PSC. Those defects are inevitably distributed at the surface and grain boundaries or in the bulk of the perovskite films, which not only result in nonradiative charge recombination and limited PCEs but also cause the rapid degradation of the perovskite absorber. − For the flexible PSC, the defects are more likely to form owing to the low surface energy, the wrinkle of the flexible substrates. , …”

Bang-bang control of a tail-less morphing wing flight

“…MAVs with morphing body [4,5,48] have distinguished themselves from other archetypal MAVs through their superior performance. However, unlike a wide variety of conventional flapping wing robots that have been developed in various sizes, ranging from insect-style flapping MAVs [10] to larger bird-style robots [22,21,39,18], these morphing designs are not well explored.…”