基于新式三点驱动的大口径FSM分析与研究

为满足光学视场不断扩大，跟踪速度不断提高的需求，对更大通光口径与偏转范围的快反镜进行了分析与研究。首先，比较了传统的压电式三点驱动与四点驱动方案后，提出了一种新式三点驱动方案，可兼顾良好的动态性能与简易的控制系统，同时避免耦合误差。然后推导了压电陶瓷致动器参数与快反镜负载惯量、偏转范围与响应频率之间的关系公式，通过有限元仿真分析了快反镜的最大偏转范围与模态频率。最后通过搭建试验平台得到测试结果，与仿真结果和理论分析结果进行对比，在镜片尺寸为长轴128 mm，短轴90 mm的椭圆的情况下，偏转范围绕短轴为±2.44 mrad，绕长轴为±3.98 mrad，一阶模态频率为447 Hz，伺服带宽为149 Hz，误差均在8%以下，验证了设计与分析的可行性与正确性。

Analysis and study on large aperture FSM based on new type of drive method

On the occasion of beam control, optical field is continually expanding and tracking speed is constantly accelerating. In order to meet the demand, FSM of larger aperture and deflection range is analyzed and studied. First, traditional three-point and four-point drive scheme is compared and a new type of drive method is proposed. This method allows for both good dynamic performance and simple control system, and coupling error can be avoided. Then formula of relationship between piezoelectric ceramic parameters and FSM load inertia, deflection range, resonant frequency is derived, the maximum deflection angle and modal frequency of FSM is analyzed through finite element method. Finally test platform is set up and FSM is tested. Test result is compared with simulation and theoretical calculation result. When load mirror size is oval-shaped that length of long axis is 128 mm and length of short axis is 90 mm, range of rotation is ±2.44 mrad of short axis and ±3.98 mrad of long axis, 1st order modal frequency of FSM is 447Hz and servo bandwidth is 149Hz, the deviation is below 8%. The design and research is verified to be feasible and correct.