李德仁. 自检校光束法区域网平差中的验后权估计[J]. 武汉大学学报 ( 信息科学版), 1982, 7(1): 16-24.
引用本文: 李德仁. 自检校光束法区域网平差中的验后权估计[J]. 武汉大学学报 ( 信息科学版), 1982, 7(1): 16-24.
Li Deren. A Posteriori Weight Estimation in Self-Calibrating Bundle Block Adjustment[J]. Geomatics and Information Science of Wuhan University, 1982, 7(1): 16-24.
Citation: Li Deren. A Posteriori Weight Estimation in Self-Calibrating Bundle Block Adjustment[J]. Geomatics and Information Science of Wuhan University, 1982, 7(1): 16-24.

自检校光束法区域网平差中的验后权估计

A Posteriori Weight Estimation in Self-Calibrating Bundle Block Adjustment

  • 摘要: 严格的自检校光束法平差的数学模型中包含三类观测值,即象片坐标、地面控制点坐标(虚拟的)和附加参数测观值。正确地选择它们的权才能保证自检校平差有稳定、可靠的结果,从而有效地补偿系统误差的影响。本文探讨用最小二乘法平差中的验后方差估计方法来估求这三类观测值的权,并对试验结果进行了分析。主要结论是:(i)自检校光束法平差中的验后方差估计有唯一收敛解。(ii)在任何情况附加参数观测值方差的估值比较准确。但在确定它的最佳权时应适当的考虑到偶然误差的系统累积作用。(iii)稀疏控制下由于地面控制观测值的多余观测分量很小,其权不可能估准,但这不会影响平差结果只有在密集控制下才有必要和可能精确地估计它的权。

     

    Abstract: A rigorous mathematical model of self-calibrating bundle adjustment consists of three Kinds of observations,i.e.observations of image coordinates,of ground coordinates of control points,and of additional parameters.It is only when their weights are correctly chosen that a stable and reliable result of the self-calibrating adjustment can be ensured and hence,the image systematic errors can be compensated efficiently.In this paper the weight estimation of these three kinds of observations is disscussed by using a posteriori variances estimation in least square adjustment,and an analysis of the experimental results is carried out.The main conclussions are(1) A posteriori variance estimation in self-calibrating bundle adjustment can always have a unique,convergent solution.(2) In any case the estimator of the additional parameters variance is comparatively exact.But when choosing the optimum weight of additional parameters we should properly consider the effect of systematic accumulation of accidental errors.(3) For the case of a sparse ground control,the weight of ground control point observations can not be estimated exactly,because the redundancy of ground point observations is very small.But it will not affect the adjusted results practically.Only for the case of dense ground control,It is neccessary and possible to estimate the weight of ground point observations more exactly.

     

/

返回文章
返回