为了减小和消除平台框架的加工、装配误差,传感器误差等对双摆框架导引头指向精度的影响,提出了应用模型线性化方法和分步最小二乘估计的指向误差标定方法.根据双摆框导引头的运动学特性,同时考虑影响指向精度的各误差项,建立了系统运动学方程.然后,重新构造运动学方程,建立了由表示控制输入指向的矢量到实际指向矢量的线性化模型.最后,根据分步求解的思路,采用最小二乘法获得了由表示控制输入指向的矢量到实测指向矢量的映射矩阵,实现了指向误差的标定.实验结果显示:标定后偏航角与俯仰角误差均值分别由原来的92.63″和75.94″减小至2.86″和2.85″,标准差也分别由原来的95.01″和77.44″减小至11.11″和11.15″.结果表明:该标定算法在视轴工作空间中具有较高的精度和良好的稳定性,且方便易行,可广泛应用于各类光电设备的指向误差标定.

To reduce and eliminate the effects of pendulum frame processing,assembly error,sensor error on the pointing accuracy of a double pendulum frame seeker,a new pointing error calibration method was introduced through model linearization and least square estimation method.The kinematic equations of the system were built according to the kinematics of the double pendulum frame seeker and each error term affecting the pointing accuracy.Then,the kinematic equations were reconstructed to establish the linear equation from the vector of control input to the actual pointing vector.Finally,according to the step-solving ideas,the least square method was used to obtain the mapping matrix from the vector of control input to the actual pointing vector and to implement the pointing calibration. The experiment results show that after calibration the means of the yaw angle error and pitch angle error have reduced from the original 92.63 "and 75.94" to 2.86 "and 2.85", respectively,and the standard deviations have also reduced from 95.01 "and 77.44" to 11.11 "and 11.15",respectively.The results demonstrate that the proposed calibration algorithm has high accuracy and good stability in the working space of the light of sight of the seeker,and can be conveniently applied.This method also is able to be widely used in pointing error calibration in various types of optoelectronic devices.