ACTA AERONAUTICAET ASTRONAUTICA SINICA >
Safety separation calculation model for multi-rotor drones in low-altitude airspace based on avoidance strategy
Received date: 2025-02-24
Revised date: 2025-03-05
Accepted date: 2025-03-27
Online published: 2025-04-17
Supported by
National Key R&D Program(2022YFB4300903);National Natural Science Foundation of China Civil Aviation Joint Research Fund(U2433217);Sichuan Province Major Science and Technology Special Project(2024ZDZX0044)
The safety separation of drones in low-altitude airspace is a fundamental prerequisite for ensuring the safe and orderly flight of low-altitude drones and for promoting the healthy development of the low-altitude economy. Low-altitude drones are predominantly of multi-rotor configurations， and the calculation of their safety separation has not yet fully taken into account the drone’s maneuver collision avoidance strategies. The main issue lies in the fact that existing models， designed for two-aircraft maneuver collision avoidance strategies， cannot adapt to complex multi-aircraft encounter scenarios. Based on encounter scenarios， this paper establishes a safety separation calculation model for multi-rotor drones by considering various factors such as the motion state of multi-rotor drones， relative velocity， environmental factors， navigation position errors， flight technical errors， and system redundancy. Using kinematic principles and the closest point of approach， this paper derives the calculation formulas for avoidance separation during both dual-aircraft and multi-aircraft encounters. Moreover， by constructing diverse collision avoidance strategies， the paper provides numerical values for dual-aircraft and multi-aircraft avoidance separation under strong wind interference and system delays through simulation methods. Finally， the safety separation for multi-aircraft encounters at different approach rates are presented， providing a reference for low-altitude operation safety and separation management.
Yunxiang CHEN , Jianping ZHANG , Zhiyuan WANG , Xiang ZOU , Yifei ZHAO , Tingfeng LAI . Safety separation calculation model for multi-rotor drones in low-altitude airspace based on avoidance strategy[J]. ACTA AERONAUTICAET ASTRONAUTICA SINICA, 2025 , 46(11) : 531887 -531887 . DOI: 10.7527/S1000-6893.2025.31887
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