面向空中威胁的无人机动态碰撞区建模与分析

针对现有方法一般是基于时间或距离的定值来确定碰撞区域的问题,提出了一种基于入侵机和无人机(UAV)运动信息的无人机动态碰撞区建模方法.首先,根据无人机与入侵机的运动状态、两机之间的最小安全距离等信息,通过几何方法得出无人机不采取任何规避机动时两机将发生碰撞区域的解析表达式,即无机动碰撞区数学模型;其次,考虑无人机的机动能力约束,计算了无人机采取最大过载转弯机动(左转或右转)时两机恰好避免碰撞发生的边界,即最大机动碰撞区数学模型;在此基础上,提出了不可规避区的概念;进而定义了安全飞行包络,它是无人机能够规避入侵机威胁的分界线;最后通过理论和仿真结合分析了影响各区域的主要因素.仿真与分析结果表明所建碰撞区不仅可以帮助无人机选择规避机动方式,而且能够帮助无人机判定常规避撞机动是否失败,并使无人机及时采取最大过载转弯机动,对无人机安全避撞决策具有实际参考价值. 

Modeling and analysis of dynamic collision region for UAV avoiding aerial intruders

In view of the existing methods to calculate collision region using certain threshold value of distance or time, an unmanned aerial vehicle (UAV) dynamic collision region model based on maneuver information of both UAV and aerial intruder was presented. Firstly, the no-maneuver collision region was proposed. In this region, UAV and intruder would undergo collision if UAV didn't execute any avoidance maneuver. Using a geometric method, a mathematical model of no-maneuver collision region was formulated utilizing the motion states of UAV and intruder, and minimum safety distance, etc. Secondly, the constraints on the UAV maneuverability were added to calculate the maximum maneuverability collision region, which was the border for UAV to avoid the collision by maximum maneuverability flight. Thirdly, the concept of non-escape region was proposed. Then the safe flight envelope was presented. This safe flight envelope was a boundary line of avoiding a collision with aerial intruder for UAV. Finally, the key factors of the proposed regions were analyzed by theoretical derivation combined with simulation. The results show that the presented collision regions are useful for UAV to select and evaluate the avoidance maneuver, and to decide whether to execute maximum maneuverability flight. The presented collision regions provide a practical guideline for UAV to ensure safe collision avoidance.