新型光学检测靶标静态指向误差修正

为检验新研制的光学检测靶标空间静态指向精度是否满足±5′设计指标要求，分析了引起指向误差的各项误差源，利用齐次坐标变换法建立了检测靶标机构的指向误差模型。通过高精度Leica全站仪标定出检测靶标的方位角误差和俯仰角误差，进一步合成检测靶标指向误差。结果显示：在标定域内最大空间静态指向误差θ_max=275″、均值θ=165.9″，均方根值σ_θ=71.5″，满足设计指标但富余量较小。为进一步提升检测靶标指向精度，利用误差模型及标定出的数据样本，采用最小二乘法曲面拟合出误差模型中的各系数，并作为方位角误差与俯仰角误差修正模型。指向误差经模型修正后，检测靶标机构在标定点和特定轨道处的总指向误差均值分别为21.1″和20.9″、均方根值分别为10.6″和7.2″，表明经误差修正后，可很大程度上减小检测靶标的空间静态指向误差。

Correction of Static Pointing Error of a Novel Optical Testing Target

The error sources that cause the pointing error are briefly analyzed to check whether the spatial static pointing error of a newly developed optical testing target satisfies the design index of 5′, and a pointing error model of target mechanism is established by the homogeneous coordinate transformation method. The azimuth and elevation errors of target are calibrated using Leica total station with high precision, and the pointing error of target is further synthesized. The calibrated results reveal that the maximum spatial static pointing error, θ_max, is 275″, the mean value, θ, is 165.9″, and the square root, σ_θ, is 71.5″. In order to further improve the pointing accuracy of target, the least square method is used to fit the coefficients in the error model based on the calibrated data samples, and the calculated error models are used as the correction models of azimuth and elevation errors. When the pointing errors are corrected by using the proposed models, the average pointing error values of target mechanism at calibration points and the specific orbit are 21.1″ and 20.9″, respectively, and the root mean square are 10.6″ and 7.2″, respectively, which indicates that the static pointing error of the new target is greatly improved after error correction.