A path replanning algorithm based on roadmap-diagram

Unmanned air vehicles (UAVs) have many useful military applications. Among the many open issues to be addressed in the development of UAVs is that of path planning. Different from the past researches, the problems presented in this paper include not only the single-mission path planning in a known environment, but also the path replanning in uncertain and mission-changeable environment. In this paper, a hybrid path replanning algorithm is proposed, which is based on roadmap-diagram. The path planning process is split into two phases: the learning phase and the query phase. Environmental information and mission constraints of UAVs are integrated into building flight roadmap and searching for paths. The implementation and experiments have demonstrated that this hybrid algorithm is an efficient, robust algorithm that is able to handle different kinds of mission parameters and generate near-optimal paths with computation times that are acceptable for real-time in-flight applications.