应用跟踪误差等效模型评价光电经纬仪跟踪性能

针对目前光电经纬仪跟踪性能室内检测方法的缺陷,提出了评价光电经纬仪跟踪性能的新方法。基于系统辨识理论建立了光电经纬仪跟踪误差等效模型,将等效正弦信号输入等效模型,通过对模型输出进行数据处理来评价光电经纬仪的跟踪性能。介绍了建立等效模型的原理和等效模型阶次,给出了根据光电经纬仪检测指标进行等效正弦信号设计的方法。为得到精确的模型参数,采用动态靶标目标角频率连续调制模式实现了对光电经纬仪动态性能的持续激励。仿真和实验结果显示,得到的跟踪误差等效模型估计误差均值为(2.5872×10-6)°≈0°,最大值为1.8″,标准差为1.1″,表明建立的等效模型能够满足跟踪性能评价要求,实现了对光电经纬仪跟踪性能的合理、准确评价。

Evaluation of tracking performance of photoelectric theodolite using equivalent model of tracking error

Considering the drawback of checking method indoor for the dynamic characteristics of tracking systems of photoelectric theodolites, a novel approach is proposed to evaluate the tracking performance of photoelectric theodolites in this paper. The equivalent mathematical model of tracking error of a photoelectric theodolite is established. On the basis of identification theory,the equivalent sine signal is inputted to the equivalent model, and then the output signals are processed to evaluate the tracking performance. The principle of the equivalent model of tracking error and the identification method of equivalent model order are introduced, and the design approach of equivalent sine signal is given according to the checking and testing desires of theodolites. Because the dynamic characteristics of the theodolite need to be inspirited fully by input signals to obtain accurate parameters of equivalent model, the frequency of dynamic target is modulated continuously. The proposed equivalent model is verified by simulation and experiments, obtained results indicate that the estimate errors of equivalent model including average error, maximum error and standard error are (2.587 2×10~(-6))°≈0°, 1.8″ and 1.1″,respectively,which shows that the equivalent model meets the needs of evaluating the tracking performance of theodolites, and achieves the accurate evaluation of tracking performance.