Dynamic Soaring Flight in Turbulence

Dynamic soaring is an engineless flight technique which extracts energy from wind gradients and has potential to enable long duration flight for small UAVs. For this paper, the authors investigate how atmospheric turbulence affects the dynamic soaring flight of a generic 3 meter wing span UAV. A previous publication established outer bounds of 7.6 m/s and 32 m/s on the range of feasible wind speed while assuming perfect control. The authors propose a periodic LQR to reject disturbances arising from atmospheric turbulence and modeling errors. Simulations with atmospheric turbulence, investigate feasibility of controlled dynamic soaring flight for wind speeds between 8 m/s and 24 m/s. Comparison between engineless and engine assisted dynamic soaring flight illustrates the importance of controlling the UAV?s energy in contrast to focusing on rejecting trajectory errors.