基于通用模型的光学载荷成像建模与分析方法

Modeling and analysis method for positioning of optical sensor based on a general model

在时敏目标精确打击、导弹预警、光学遥感和测绘等应用过程中,光学载荷成像定位精度是最为重要的性能指标之一。光学载荷成像变换过程可以等效为目标点到像点的坐标变换过程。提出了一种基于成像链路分解与有限差分的光学载荷成像定位建模和分析方法。分析了典型光学载荷成像链路的组成,定义了成像变换坐标系统,分析了坐标系之间的变换关系;基于光学载荷成像模式,建立了光学载荷通用成像定位模型;提出了基于有限差分的光学载荷成像定位系统模型参数灵敏度和成像定位误差计算方法;采用摄影测量解析计算模型对所提出的模型方法进行了验证。结果表明,该方法可以得到高精度的计算结果,由于考虑了成像链路的更多细节,所以可实现更加复杂的系统建模和分析。

Imaging positioning accuracy is one of the most important performance indexes for optical sensor in applications of precision striking of time critical target, forewarning of ballistic missile, optical remote-sensing, and so on. The imaging procedure of optical sensor can be treated equivalent to the position transforming from target point to image point. A modeling and analyzing method based on imaging chain decomposition and finite difference is put forward. The imaging chains of optical sensor in typical applications are analyzed, the general imaging coordinate system is defined and the transformation relationships are described. A general imaging positioning model of optical sensor is built up. The calculating method for the sensitivities of the model parameters in the imaging positioning system are put forward based on finite difference, and the imaging positioning accuracy is calculated and analyzed. The analytical photogrammetric model is taken to verify the performance of this method. The results show that the method has high calculating precision, and because its capability of considering more details, this method can handle more complicated systems.