为实现星载三线阵CCD相机的相机参数在轨测量, 提出了一种六自由度微位移测量方法。高亮度LED输出光被准直并耦合到输入光纤。输出光纤末端固定在可移动的被测物体上。光纤输出由多个光纤准直器(≥4)准直, 并由系统固定部分中的多个区域阵列的CCD相机(≥4)捕获。根据CCD图像中光点的位置变化来求解被测物体的六自由度位移。为了验证系统模型和六自由度位移计算程序, 对该方法进行了理论分析和仿真。结果表明: 当平移位移小于100 μm且旋转位移小于6′时, 典型的4准直测量系统求解误差小于10-5 μm和10-4′。并且, 当准直器的光斑位置的两个坐标方向上添加-0.5~0.5 μm的随机量时, 平移误差和旋转误差的3σ分别为0.9 μm和0.012′。

In order to realize in-orbit measurement of the parameters of three-line array satellite-borne CCD camera, a method for measuring 6-DOF (Degree of Freedom) micro-displacement was proposed in this paper. The LED output light with high brightness was collimated and coupled to the input optical fiber. The end of the output fiber was fixed to the movable object to be measured. The fiber outputs were collimated by multiple fiber collimators (≥4) and captured by multiple area array CCD cameras (≥4) in the fixed part of the system. The 6-DOF displacement of the measured object was solved according to the position change of the light spot in the CCD image. In order to validate the model of the system and 6-DOF displacement calculation program, the proposed method was theoretically analyzed and simulated. The results show that both the maximum translational error and rotational error of the typical 4-collimation measurement system are under 10-5 μm and 10-4′ when the translational displacement is less than 100 μm and the rotational displacement is less than 6′. And the limit errors (3σ) of the translational errors and rotational errors are respectively 0.9 μm and 0.012′ when the random quantities of -0.5-0.5 μm are added to the two coordinate directions of the position of the light spot of the collimators.