基于立体视觉的相对姿态确定算法可观性分析  

Observability analysis of relative attitude determination algorithm based on stereo vision

作　　者：白博[1] 周军[1] 于晓洲[1] 

机构地区：[1]西北工业大学精确制导与控制研究所,西安710072

出　　处：《中国惯性技术学报》2010年第6期723-728,共6页Journal of Chinese Inertial Technology

基　　金：教育部博士点基金(20070699004);西北工业大学科技创新基金(2008KJ02010)

摘　　要：针对基于立体视觉的相对姿态确定算法无法正确估计出陀螺误差这一问题,分析了该算法中各个状态的可观性。首先,根据相对姿态误差方程和立体视觉测量方程建立滤波器模型。其次通过选取不同变量作为误差方程的状态,确定了系统中的不可观子空间。进而对系统的结构分解揭示出,该相对姿态确定算法仅能估计出主从星之间的相对姿态和其陀螺误差的线性组合这一结论。从系统结构分解的分析中还可以看出,当立体视觉系统测得的特征点大于两个以上时,增加特征点个数对提高陀螺误差的可观测性是没有帮助的。最终的仿真结果证明了论述的正确性。To solve the problem that stereo-vision-based relative attitude determination algorithm couldn＇t correctly estimate gyro errors,the observability of each state in this algorithm is studied.Firstly,the filter model is designed based on the relative attitude error equation and stereo-vision measurement equation.Secondly,the unobservable subspace of the system is determined by choosing different variables as error model＇s states.Furthermore,the analysis is made on system structure decomposition,which reveals that this algorithm can only determine the relative attitude and gyro error＇s linear combination between the master star and the slave one,and when the feature points measured by stereo vision system are greater than two,increasing the number of feature points gives little help for improving the observability of gyro error.The simulation result validates the former discussion.

关 键 词：可观性分析 立体视觉 相对姿态确定 陀螺误差 

分 类 号：U666.1[交通运输工程—船舶及航道工程]