介绍了用于一对多激光通信组网控制系统的光斑跟踪闭环系统。在伺服转台位置闭环的基础上, 讨论以CCD相机为敏感器, 以二维伺服转台为执行器的光闭环系统。介绍了跟踪系统的数学原理, 研究了光闭环各环节的静态动态误差及开环闭环响应。在理论计算和数学仿真后, 编写了闭环跟踪程序。采用经典PID控制与前馈相结合的控制算法, 进一步提高了伺服带宽, 保证了系统的稳定性。对星间激光通信的光斑位置进行了跟踪试验, 结果显示跟踪误差为3σ ≈ 136 μrad, 基本符合空间激光通信组网系统激光束的指向要求。得到的结果验证了控制策略的可行性, 为多光束伺服打下了基础。

A spot tracking closed-loop system for the control of a one-to-many laser communication net was introduced. On the basis of the closed-loop position of the servo rotary table, the closed-loop beam tracking system which takes a CCD camera as the sensor and a two-dimensional servo rotary table as the actuator was discussed particularly. The mathematical principle of the tracking system was introduced and static and dynamic errors of every link in the closed-loop beam system and the responses of open-loop and close-loop were researched also. After theoretical calculation and mathematical simulation , a closed-loop tracking programming was written. Then, a control algorithm combined the classical PID control and feedforward control was used to further improve the servo bandwidth and to guarantee the stability of the system. The tracking experiment on spot positions in laser communication was performed and the result shows that tracking error is 3σ≈136 μrad, which meets the demands of laser pointing in laser communication nets. The obtained results verify the feasibility of control strategy, and lay the foundation for the multiple beam servo.