在复杂地形下三维UAV航迹规划的改进A^(*)算法

3D UAV track planning based on improved A^(*) algorithm in complex terrain

针对无人机在复杂三维空间中无法及时有效规划航迹问题,提出一种改进的A^(*)算法。首先对无人机飞行俯仰角与偏航角进行约束,缩小航迹节点的扩展区域,其次为了防止未能及时探知地形障碍出现的航迹与障碍区域相交情况,引入危险因子并对节点附近搜索区域进行探测,提高算法提前预知风险的能力,最后为了满足实际无人机飞行需求,使用B样条曲线的方法生成连续平滑可跟踪航迹。仿真结果表明:改进算法规划的航迹满足约束且有较强的可行性和鲁棒性,航迹安全程度远远高于传统算法。

An improved A^(*) algorithm is proposed to solve the problem that UAV can’t plan its trajectory in time and effectively in complex 3 D space. Firstly,flight pitch angle and yaw angle of the UAV are constrained to reduce the extended area of the track node. Secondly,in order to prevent being failed to detect condition of intersection of track and obstacle area in time,that terrain obstacle occur the danger factor is introduced and the search area near the node is detected,so as to improve the ability of the algorithm to predict the risk in advance. Finally,in order to meet the actual flight requirements of UAV,B-spline curve method is used to generate a continuous and smooth track. The simulation results show that the track planned by the improved algorithm satisfies the constraints and has strong feasibility and robustness,and the degree of track safety is much higher than the traditional algorithm.