Modeling and correction for the optical axis pointing error of an airborne electro-optical platform

Appl Opt. 2019 Aug 10;58(23):6455-6463. doi: 10.1364/AO.58.006455.

Abstract

Optical axis pointing accuracy is an important index of airborne electro-optical (EO) platforms. In this work, we aim to correct the optical axis pointing angle of an airborne EO platform by digital compensation. First, a basic parameter model (BPM) of pointing error with clear physical significance is established by analyzing the physical structure and error source of the EO platform. Then, to suppress the nonlinear factors in the error, we propose an improved algorithm of a semi-parametric regression model based on the BPM. Numerical simulation analysis shows that the improved algorithm inherits the advantages of the BPM, such as fewer model parameters and clear physical significance, and can improve the correction effect. Finally, experimental results show that the mean square error of the azimuth angle is reduced from more than 110'' to less than 4'', and that of the elevation angle is reduced from more than 75'' to less than 3''. According to the results obtained, the proposed correction model can improve the optical axis pointing accuracy of an airborne EO platform quickly and effectively, which has significant application value.