针对光轴控制系统中广泛使用的压电倾斜镜,分析了其基本工作原理和数学模型,描述了遗传算法在模型中的辨识过程。针对大口径压电倾斜镜,搭建了频率响应测试系统,实现了对压电倾斜镜传递函数的参数辨识。对比辨识传递函数的频率响应与实际测量数据,并对系统中存在的多个谐振点的辨识精度进行分析。实验结果表明,在各个谐振点处,遗传算法获得的传递函数频率响应与实际测量数据具有较高的一致性,利用该算法得到的传递函数能更为准确地分析光轴控制系统的动态特性,有针对性地设计先进的控制算法,从而达到提高光轴控制系统性能的目的。

The basic working principle and mathematical model for a fast-steering mirror driven by PZT, which is a type of mirror widely used in optical-axis control systems, are analyzed, and the identification process of genetic algorithms in the model is described. A system for measuring the frequency response of a large-aperture fast-steering mirror driven by PZT is set up to realize parameter identification for the transfer function. The frequency response of the identified transfer function and the actual measured data are compared, and the identification accuracy of multiple resonance points in the system is analyzed. The experimental results show that at each resonance point, the frequency response of the transfer function obtained by the genetic algorithm is consistent with the measured data. The results also show that the transfer function obtained by this algorithm can analyze the dynamic characteristics of optical axis control system more accurately, and we can design advanced control algorithm, thus improving the performance of the optical-axis control system.