基于Zernike矩的高精度太阳图像质心提取算法  

Zernike Moment Based High-Accuracy Sun Image Centroid Algorithm

作　　者：杨鹏[1,2] 谢立[1,2] 刘济林[1,2] 

机构地区：[1]浙江大学信息与电子工程学系,杭州310027 [2]浙江省综合信息网技术重点实验室,杭州310027

出　　处：《宇航学报》2011年第9期1963-1970,共8页Journal of Astronautics

基　　金：国家自然科学基金重点项目(60534070)

摘　　要：在基于太阳观测的月球车天文导航系统中,针对太阳传感器中图像噪声以及典型图像退化的不良影响,提出了一种基于Zernike矩的高精度太阳质心提取算法。采用Sobel算子进行边缘检测,Zernike矩重定位亚像素边缘,用最小二乘法拟合圆心。而当图像存在退化时,进行有效圆边缘点检测后,再用该法提取质心。从理论上分析了Zernike矩亚像素边缘检测对圆拟合法的改进作用。利用仿真图像和地表实验图像,将本文方法与传统的重心法、带阈值的重心法和圆拟合法进行了比较。结果表明,本文方法精度更高,具有更好的稳定性,可以对月球车天文导航精度的提高起良好作用。In order to reduce the image noise and typical image degradation in sun sensor,a novel high resolution Zernike moments based centroid algorithm is proposed for the sun observation based lunar rover celestial navigation system in this paper.The edge is detected by Sobel operator,and is relocated at sub-pixel accuracy by the Zernike moment operator,then the image centroid is fitted by least square method.Also degraded images are processed by means of the proposed effective circle edge point detection method before the Zernike moment based method is used.It is known from the theoretical analysis that the Zernike moment edge detection improves the accuracy of circle fitting method.In simulation and experiment,this method is compared with the traditional centroid method,the threshold based centroid method and the circle fitting method.The results show that this method has higher accuracy and higher stability,and can play an important role in the improvement on lunar rover＇s navigation accuracy.

关 键 词：质心提取 ZERNIKE矩 有效圆边缘点检测 圆拟合法 太阳图像 月球车天文导航 

分 类 号：V448.22[航空宇航科学与技术—飞行器设计]