摘要
针对固定翼无人机在动态环境下沿参考轨迹飞行时可能与未知障碍物发生碰撞的问题,提出了可实时避障的路径跟踪算法.采用3维毕达哥拉斯速端曲线(PH)作为参考飞行路径.PH曲线具有曲率连续、曲线平滑等特性,能满足固定翼无人机运动学约束,适于无人机飞行跟踪控制实现.给出了3维空间内稳定跟踪参数化曲线路径的充分条件.设计了非线性模型预测控制器使无人机能稳定跟踪3维PH参考路径,并改进了目标函数形式使无人机在沿参考路径飞行时能及时避开环境中未知的大型静止障碍物和移动障碍物,在避障后继续朝目标点飞行.最后通过MATLAB仿真实验验证了算法的有效性.
When flying in dynamic environment, fixed-wing UAV （unmanned aerial vehicle） following the reference path will collide with unknown obstacles. To solve the problems, a real-time obstacle avoidance path following algorithm is proposed. Firstly, 3-D Pythagorean hodograph （PH） is adopted as a reference flight path for its continuous curvature and smoothness, which is able to meet the kinematical constraint of fixed-wing UAV and is more suitable for path following. Then, sufficient conditions of stably following a parameterized path in three dimensions are given. A nonlinear model predictive controller is designed for 3-D PH path following, in which the form of objective function is modified to make the UAV timely avoid large unknown static and moving obstacles and fly towards the target after obstacle avoidance during path following. Finally, MATLAB based simulation experiments are performed to demonstrate the effectiveness of the algorithm.
出处
《机器人》
EI
CSCD
北大核心
2014年第1期83-91,共9页
Robot
基金
国防预研项目(41101060101)
关键词
避障
路径跟踪
毕达哥拉斯速端曲线
无人机
obstacle avoidance
path following
PH （Pythagorean hodograph）
UAV （unmanned aerial vehicle）
