伺服转台回转角度误差的不确定度研究

Research on Uncertainty of Rotating Angle Error of Servo Turntable

回转角度误差是伺服转台的主要性能指标之一,对导航系统漂移误差的补偿起着决定性作用。本文利用试验数据及一系列处理方法实现了对双轴伺服转台回转角度误差的不确定度表征。根据试验数据的特点利用频谱分析方法对数据结构进行了研究,并对其中的常值误差和一次分量等成分的来源进行了分析处理;解决了二次分量不满足测量不确定度对数据平稳性要求的问题;针对测试方法提出了不确定度的数学模型,对其中已剔除的平面镜安装误差即数据中一次分量,根据实际情况在不确定度中重新计入了其影响。最后给出了回转角的测量不确定度。本文为类似的研究提供了一整套数据处理方法;伺服转台不确定度的计算为精确导航提供了可能。

Rotation error of servo turntable is one of primary characteristics that take the decisive role in drifting error com- pensation of guidance for navigation. Uncertainty of the error was given by experiment datum and by a series of processing meth- ods. According to the characteristics of the datum, the structure of the datum was analyzed using spectrum method, and the con- stant error and primary harmonic component were analyzed and disposed. A returning method was used on the second harmonic component of the datum to solve the problem that uncertainty should be calculated on stationary raralom datum before calculating the uncertainty. The component was removed and after finishing the calculation the component was add on the uncertainty based on the experiment method. A model of the uncertainty was put forward, and the influence of the first harmonic component, which had been removed before, was taken into consideration according the actual situation. This article gave out a set of methods about the data processing; and the uncertainty gave a possibility for accurate guidance. Long-time using has testified that the result of the uncertainty is reliable and practical.