Optimal air route flight conflict resolution based on receding horizon control

Abstract

To deal with the air route flight conflicts caused by abnormal situations during four-dimensional based air traffic operation, the air route flight conflict resolution problem for two aircrafts was addressed. Based on the optimized static single heading angle or ground speed adjustment strategy, we proposed an optimized dynamic mixed conflict resolution strategy based on Receding Horizon Control (RHC), which considered the possibility of one aircraft's ground speed variation. In particular, the wind speed vector disturbance during conflict resolution might lead to a model mismatch, so the maximum likelihood estimation method and the Newton–Raphson iterative algorithm were employed to identify the wind speed vector using the aircraft true airspeed inputs and ground based trajectory measurements. Moreover, we considered the convergence of conflict resolution method based on RHC and proposed the pre-condition that local and global optimization resolution can be achieved. We compared three situations, i.e., static single strategy optimization, dynamic mixed strategy optimization using RHC with one aircraft's ground speed variation, and dynamic mixed strategy optimization using RHC with the wind speed vector disturbance. We demonstrated that the dynamic mixed strategy responds to one aircraft's ground speed disturbance quickly, and resolved conflict by track angle and ground speed adjustments in an effective manner after the wind speed vector being identified accurately.