基于敏感度分析的三轴转台关键误差源辨识

为深入研究三轴转台各误差源对指向误差的影响程度,完成对其中关键因素的有效识别,提出了一种基于敏感度分析的三轴转台关键误差源辨识方法。以某三轴仿真转台为研究对象,首先基于多体系统运动学理论建立其指向误差模型,然后采用矩阵微分法推导出各误差源的敏感度系数表达式,最后通过计算转台完整运动周期下各误差源的敏感度系数,识别出对三轴转台指向误差影响较大的关键性误差源。结果表明:转台中框z向倾角回转误差等4项误差源对方位向指向误差的影响最大,而中框回转位置误差等6向误差源是影响俯仰向指向误差的主要因素。该方法可以为三轴转台的精度分析与设计提供理论依据和参考。

Identification of Key Error Sources from Three-Axis Turntable Based on Sensitivity Analysis

To explore the influence of the error sources on the pointing error for the three-axis turntable and identity the key factors effectively, a method for key error sources identification is proposed using the sensitivity analysis. Firstly, the model of the pointing error for a three-axis turntable is established based on the theory of multi-body system kinematics. Then the mathematical expression for error source sensitivity coefficient is deduced with matrix differential method. Through the calculation of the error sources sensitivity coefficient for the whole movement period of the three-axis turntable, the key error sources are identified. The results demonstrate that the four error sources like the obliquity error of rotation middle-axis along the z axis have the greatest impact on the azimuth pointing error. And the pitching pointing error is mainly affected by the six error sources like the middle-axis rotation error. The analytical method above can provide theoretical basis and reference for the precision analysis and design of the three-axis turntable.