两轴四框结构光电吊舱, 内框多采用力矩电机直驱, 稳定精度仅为数10 μrad。为达到更高精度的μrad量级, 提出一种压电陶瓷驱动柔性支承的精级回转驱动机构, 作为光电吊舱的内框驱动。介绍了精级回转驱动机构的构型方案, 并对压电陶瓷的驱动能力进行了探讨, 对柔性支承的回转刚度、固有频率、几何参数进行了详细设计。建立了机电仿真模型, 制造了原理样机并进行了性能测试, 其主要性能指标为: 行程509.1 μrad, 分辨率优于0.5 μrad, 1 Hz、100 μrad的正弦信号跟踪误差小于3 μrad, 固有频率约1 kHz, 均满足设计目标。

The inner gimbal of electro-optical pod with two-axis and four-gimbal structure is usually driven directly by torque motor, its stability accuracy is only tens of micro radians. To achieve the stability accuracy of several micro radians, a flexure-based precision rotary drive mechanism driven by piezoelectric actuators was proposed, which acted as the inner drive of electro-optical pod. The configuration scheme of precision rotary drive mechanism was introduced, and the drive capability of piezoelectric ceramics was explored. The rotation stiffness, resonance frequency and geometric parameters were designed in detail. The electromechanical simulation model was obtained. In addition,a prototype was fabricated and tested for performance verification. The results show that the travel range is 509.1 μrad, the resolution is better than 0.5 μrad, the sinusoidal signal tracking error of 1 Hz and 100 μrad is less than 3 μrad, and the resonance frequency is about 1 KHz. These results can all meet the design goals.