Abstract:

There is a risk of collision in the batch operation of logistics UAVs. To evaluate the collision probability between UAVs in the air, a model was proposed to analyze the collision risk of logistics UAVs in the aerial operation stage. A UAV collision probability model with the double errors of positioning and velocity was proposed based on the conflict zone theory, and the logistics UAV collision probability variations are analyzed from different angles. The key risk factors in small civil UAV accident/incident data were analyzed and identified based on the data from the Federal Aviation Administration of the United States. The UAV safety flight interval model was proposed based on the logistics UAV failure data of 20 thousand flight hours to determine the shortest flight interval under the acceptable safety level. Furthermore, the effects of track angles and wind directions on the collision probability between UAVs under constant flight intervals were investigated. The results showed that the risk for all flight scenarios was acceptable when the shortest safety interval between logistics UAVs exceeded 90.71 m. When the track angle was 30, 60, and 90°, the collision probability varied little with the wind direction. Specifically, the collision probability was maintained constantly when the track angle was 90°. The collision probability varied a lot when the angle was 140°, thereby the safe flight of the UAV was sensitive to environmental factors.

Key words: positioning error, speed error, logistics unmanned aerial vehicle(UAV), collision probability, conflict zones, track corner, flight interval