Vision based navigation system of UAV and improvements of the corresponding filtering algorithm
-
摘要: 设计了一种无人机视觉/惯性组合导航系统,将无人机和地标点的运动模型作为状态方程,视觉信息作为观测量构建了与之对应的滤波模型.在滤波处理上,采用了复杂加性噪声模型对系统噪声进行建模处理;将小波分析引入到UKF (Unscented Kalman Filter)滤波中得到小波-UKF滤波算法,以此克服视觉观测噪声对滤波的影响;采用最大后验概率准则(MAP ,Maximum A Posterior)自适应估计观测噪声协方差阵,并将其反馈到滤波过程中克服了小波处理后观测噪声方差阵不易确定的不足.仿真结果证明:对滤波算法的改进可以有效地提高滤波估计的精度.
-
关键词:
- 视觉导航 /
- unscented卡尔曼滤波 /
- 小波分析 /
- 复杂加性噪声 /
- 自适应
Abstract: A vision/inertial integrated navigation system was built. The corresponding filtering model was established by treating the motion models of aerial vehicle and landmark as the system function and the vision information as the observation. Complex additive noise model was adopted to describe the system noise in the filtering process. The wavelet-unscented Kalman filter (UKF) algorithm was obtained by introducing the wavelet analysis into UKF, thus the influence of vision observation noise on the filtering was inhibited successfully. Maximum a posterior (MAP) adaptive method was utilized to estimate the observation noise covariance matrix, which was further fed back into UKF to overcome the difficulties in identifying the covariance of observation after the wavelet de-noising. The simulation proved that the improvements in the filtering process to be effective in increasing the filtering accuracy. -
[1] Strelow D W.Motion estimation from image and inertial measurements .Pittsburgh,PA:School of Computer Science,Carnegie Mellon University,2004 [2] Kehoe J J.Autopilot development for a micro air vehicle using vision-based attitude estimation .Florida:Aerospace Engineering Department,University of Florida,2004 [3] Kim J,Sukkarieh S.Autonomous airborne navigation in unknown terrain environments[J].IEEE Transactions on Aerospace and Electronic System,2004,40(3):1031-1045 [4] Lee D J,Alfriend K T.Precise real-time satellite orbit determination using the unscented kalman filter[J].Advances in the Astronautical Sciences,2003,114(3):1853-1872 [5] 王海彬,陈华华,顾伟康.基于视觉导航的三维重建算法误差分析及补偿[J].传感技术学报,2004,12(4):556-559 Wang Haibin,Chen Huahua,Gu Weikang.Error analysis and compensate of 3D reconstruction algorithm based on vision navigation[J].Journal of Transcluction Technology,2004,12(4):556-559(in Chinese) [6] Wu Xuedong,Jiang Xinhua,Zheng Rongjin,et al.An application of unscented kalman filter for pose and motion estimation based on monocular vision // IEEE.2006 IEEE International Symposium on Industrial Electronics.Montreal,Quebec,Canada:IEEE Press,2006:2614-2619 [7] Qi Song,Qi Juntong,Han Jianda.An adaptive UKF algorithm and its application in mobile robot control // IEEE.International Conference on Robotics and Biomimetics.Kunming,China:IEEE Press,2006:1117-1122 [8] 隋树林,姚文龙,赵晓伟.基于小波-UKF 的自主光学导航方法研究[J].系统仿真学报,2007,19(12):2776-2778 Sui Shulin,Yao Wenlong,Zhao Xiaowei.Study of autonomous optical navigation based on wavelet-UKF[J].Journal of System Simulation,2007,19(12):2776-2778(in Chinese) [9] 张少辉,沈晓蓉,范耀祖.一种基于图像特征点提取及匹配的方法[J].北京航空航天大学学报,2008,34(5):516-519 Zhang Shaohui,Shen Xiaorong,Fan Yaozu.Method in image-s feature extraction and matching[J].Journal of Beijing University of Aeronautics and Astronautics,2008,34(5):516-519 (in Chinese) [10] Xu Chao,Fan Yaozu,Zhou Yanli.A strong local invariant descriptor and mismatched points eliminating method in vision navigation // Wang Jixin.Proceedings of IEEE International Symposium on Knowledge Acquisition and Modeling Workshop.Wuhan,China:IEEE Press,2008:470-473 [11] 严恭敏,严卫生,徐德民.简化UKF滤波在SINS大失准角初始对准中的应用[J].中国惯性技术学报,2008,16(3):253-267 Yan Gongmin,Yan Weisheng,Xu Demin.Application of simplified UKF in SINS initial alignment for large misalignment angles[J].Journal of Chinese Inertial Technology,2008,16(3):253-267(in Chinese) [12] Zhe Jiang,Qi Song,He Yuqing,et al.A novel adaptive unscented kalman filter for nonlinear estimation // IEEE.Proceedings of the 46th IEEE Conference on Decision and Control.New Orleans,Los Angeles,USA:IEEE Press,2007:4293-4298 [13] Sui Shulin,Yao Wenlong,Sun Lihong,et al.A novel unscented kalman filter in autonomous optical navigation // IEEE.26th Chinese Control Conference.Zhangjiajie,Hunan,China:IEEE Press,2007:462-466 [14] 邓自立.自校正滤波器理论及其应用[M].哈尔滨:哈尔滨工业大学出版社,2003:161-177 Deng Zili.Self-tuning filtering theory with applications[M].Harbin:Harbin Industry University Press,2003:161-177 (in Chinese)
点击查看大图
计量
- 文章访问数: 5092
- HTML全文浏览量: 308
- PDF下载量: 1378
- 被引次数: 0