自由飞行下基于随机微分方程的碰撞风险模型

Assessment model of collision risk based on stochastic differential equation for free flight

未来的飞行模式将逐步由被动指挥转向"自由飞行"。首先分析了飞机在空中的状态过程,建立了基于随机微分方程的碰撞风险评估模型;其次采用了停滞时间的概念以减轻计算量,并把影响飞机碰撞风险的事件因素进行分类,实现模型的简化;最后运用Monte Carlo模拟技术进行仿真,算出不同事件分类情况下的交汇概率,从而找出合理的安全间隔。将一定间隔下的碰撞风险与目前安全目标水平相比较,符合安全水平要求,表明该模型有效。

Future flight model will gradually shift from passive command to 'free flight'.Firstly,the hybrid stochastic state of the aircraft in the air is analyzed.Assessment model of air collision risk based on stochastic differential equation is established.Secondly,the concept of the stopping time is introduced to reduce the computation;the effect events of aircraft collision risk are classed to simplify the model.Finally,a specific example is simulated by using Monte Carlo technique.The incrossing rates of different classification events are computed.Compared to the target level of safety,the collision risk with ideal separation meets the safety standards required and shows that the model is rational and feasible.