激光惯性约束聚变对机械式拼接光栅的稳定性提出更高的要求,采用全闭环控制技术实现光栅拼接的高稳定性。为提高光栅装置的拼接精度,分析柔性机构的运动性能,从理论上推导精确的拼接机构运动控制算法;以电容微位移传感器作为反馈元件,研究动光栅位姿监测算法,实现动光栅位姿的实时监测。综合应用拼接机构运动控制算法和光栅位姿监测算法,实现光栅拼接稳定性的单神经元自校正PID全闭环控制;设计了光学检测系统,进行光栅拼接试验,并测试拼接装置的运动精度和稳定性,评估光栅拼接稳定性全闭环控制技术的可行性。试验结果表明拼接机构定位精度为0.2μrad/步(转动)、10 nm/步(平动),转动稳定精度小于1.2μrad/30 min、平动小于24 nm/30 min(平动),满足光栅拼接任务的要求。
The inertial confinement fusion puts forward higher requirement on the stability of the mechanical grating tiling. The full closed-loop control technology is applied to achieve high stability of the grating tiling. In order to improve the stitching accuracy of the grating device, the motion performance of flexible mechanism is analyzed and the accurate motion control algorithm of the splicing mechanism is deduced in theory. With using the capacitive micro displacement sensor as the feedback element, the position and posture monitoring algorithm is derived. The single neuron adaptive PID full closed-loop control for the stability of the grating tiling is realized by comprehensive application of the motion control algorithm and the position and posture monitoring algorithm. The optics inspection system is designed to carry out the stitching experiment and the movement accuracy and stability of the splicing device are tested to evaluate the feasibility of the full closed-loop control to the stability of the grating tiling. The experimental results show that the stitching accuracy reaches 0.2 μrad/step(rotation) and 10 nm/step(translation), and the stabilization precision is less than 1.2 μrad/30 min(rotation) and the translational accuracy is less them 24 nm/30 min(translation). The stitching accuracy and the stabilization precision meet the requirement of the grating splicing task.