考虑相干激光雷达对光束波前的要求, 设计了压电驱动双面快速指向镜系统以实现相干激光遥感探测的高精度大范围指向定位。研究了系统的机械结构和电子学控制方法。结合指向角度、通光口径及信号带宽的实际工程应用需求, 选择了合理的致动器和位移放大机构。针对压电陶瓷固有的迟滞和蠕变等非线性效应, 设计了以应变片作为位移传感器的模拟比例-积分-微分(Proportion Intergration Differentiation, PID)闭环反馈控制方法。在仿真分析指向镜固有模态频率的基础上, 确定了周边支撑的反射镜支撑方式。实验结果表明, 该指向系统能够达到指向范围为27 mrad×27 mrad、绝对定位精度优于27 μrad、偏转速率为2.7 rad/s的指标, 基本满足激光遥感探测对探测范围、探测精度、探测速率等指向定位的要求。

According to the requirements of laser radars for beam wavefront, a piezo-activated double-sided and fast-steering mirror was designed to realize the high-accuracy beam pointing and wide scanning range of a coherent laser remote system. The mechanical structure of the system and its electronics control method were researched. In consideration of the system requirements for the point angle, clear aperture and the signal bandwidth, an actuator and a displacement amplification mechanism were chosen. To overcome the nonlinear effect of piezoelectric ceramics, such as hysteresis and creep, an analog Proportion Intergration Differentiation(PID) closed-loop feedback control method by taking a strain gauge as the displacement sensor was designed. By analysis of the natural modal frequencies of the pointing mirror, the circum support was determined as the mirror support manner. Experimental results indicate that the pointing accuracy and scanning speed of the system are respectively 27 μrad and 2.7 rad/s at the range of 27 mrad×27 mrad, which satisfies the requirements of laser remote sensing for detection ranges, detection accuracy and detection speeds.