分析了光电跟踪系统组成及控制原理，并对速度稳定回路的各个环节进行了建模.通过跟踪环架的开环频率特性测试，绘制出跟踪环架的实际频率特性曲线，运用最小二乘法对测试数据进行拟合，建立了控制对象的数学模型.与实测曲线相比，取得了较好的一致性.

The composing and controlling diagram block of the optoelectronic tracking system were analyzed，and every part of velocity stabilization loop was modeled. Through the open-loop frequency characteristic test of the gimbal, the actual frequency characteristic curve of the tracking system was plotted. By using total least square algorithm on testing data to approach curve, the mathematics model of the controlled object was built. Comparing with the actual frequency characteristic curve, the model has made good coherence.