Research on the Algorithm of Online Route Re-planning for UAV Formation

Abstract

In order to solve the real-time and robust problem of online flight path re-planning when UAV encounters new threat sources in the course of navigation, an online flight route re-planning algorithm based on sparse A* algorithm is proposed. Based on the threat model of UAV, the online route re-planning strategy is analyzed. When the UAV detects a new threat in the course of navigation, according to the current position of the UAV formation and the position of the threat source, a route that can safely bypass the threat source is quickly re-planned. In order to meet the requirements of real-time and robustness, the node expansion and update strategy of the improved sparse A* algorithm and the hierarchical planning combined with the size step size are adopted. The simulation system of UAV formation navigation is established to verify the process of online route re-planning. The number of expansion nodes and convergence time of algorithm before and after the improvement are compared, and the track accuracy of fine planning based on rough planning is compared. The experimental results show that the improved algorithm can speed up the search speed and meet the real-time requirements of online route re-planning.