空间相机偏流角的间歇式实时调整

Batch-type real-time adjustment for drift angle of space camera

空间相机摄像时对其偏流角进行实时调整,可以减小偏流角姿态变化对成像质量的影响,延长一次性连续摄像时间并使用较多的TDI积分级数进行摄像。本文对偏流角实时调整的需求进行了详细分析并给出了实时调整策略;然后,介绍了偏流角调整系统的构成及实时调整的工作原理;最后,提出了一种间歇式实时调整方案并进行了实验。实验结果表明:摄像过程中偏流角偏差值可以调整在4.2′以内,调整后误差≤72.17″,一次调整时间<1s,偏流角调整过程中图像的调制传递函数(MTF)值为99.67%。提出的间歇式实时调整方法可满足摄像过程中对偏流角实时且长时间调整,且对图像无本质影响的要求。

Adjusting the drift angles of a space camera on real time in photographing could decrease the influence of the attitude change on image quality and could prolong continuous photographic time with more TDI integral progressions. In this paper, the requirements adjusting drift angles on real-time were analyzed in detail and the real-time adjusting tactics were presented. Then, the structure of a drift angle adjusting system and the operating principle of real-time adjusting were introduced. Finally, a batch-type real-time adjusting method was presented and experimented. Experimental results indicate that the partial difference of drift angle can be adjusted to below 4.2′ with the adjusting error no larger than 72. 17″ and the adjusting time less than 1 s. Moreover, Modulation Transfer Function （MTF） of the image is 99.67%,while the drift angles are adjusted. These results show that the proposed method can meet the requirements for adjusting drift angles on real-time and long period without essential influence on images in photographing process.