Experimental study on aerodynamic characteristics of fixed-wing UAV air docking

Abstract

With the increasing use of unmanned aerial vehicle (UAV) clusters, efforts are underway to effectively improve their endurance time and flight altitude. Chained wing technology is such a technology, which makes cluster UAVs form a combination with high aspect ratio through wingtip connection, thus improving the endurance time and flight altitude. However, existing research on chained wing technology focuses on evaluating the feasibility and improving the performance of chained wing flight. The key technologies for wingtip air-docking have not yet been adequately investigated. This study evaluates the aerodynamic performance of UAV wingtip docking based on a wind-tunnel experiment. The quasi-steady aerodynamic data of two wings during wingtip approach are obtained. And an explicit, fast-response model is developed for the rolling moment coefficient of the UAV based on the symmetric inverse proportional function. The results demonstrate that the developed model can quickly and accurately evaluate the rolling moment coefficient of the rear UAV at different relative positions under specific conditions. These findings of this study can serve as a reference for real-time prediction and attitude control in fixed-wing UAVs during air docking, and provide an idea for the active cancellation of wing interaction in the process of wingtip connection of two aircraft.