飞秒激光跟踪仪动态测量误差机理分析与测量不确定度表征方法研究

Based on the development of the laser tracker, the novel femtosecond laser tracker adopts the most advanced technology of absolute distance measurement, which expands the measurement range and enhances the measurement accuracy. Currently, there are a large numbers of research papers on the measurement error of traditional laser tracker, which only covers the analysis of static measurement error and cannot meet the demands of real-time dynamic characteristic. However, there is few studies on the dynamic measurement error of the femtosecond laser tracker. This project aims to analyze distance measurement error and dynamic angle measurement error of femtosecond laser tracker. In addition, it will provide dynamic error compensation and correction methods through the establishment of physical and mathematical models. Moreover, by taking measurement distance and angle error into overall consideration, it will propose the measurement uncertainty expression according to measurement tasks. This study will theoretically support distance measurement accuracy of femtosecond laser frequency comb and technologically support dynamic measurement error of femtosecond laser tracker.

新型飞秒激光跟踪仪是在现有激光跟踪仪研制的基础上，采用最先进的飞秒激光绝对测距原理，能够扩大测量范围并提高测量精度。目前国内外对于传统激光跟踪仪测量误差研究报道较多，属于静态测量误差分析范畴，已经难以满足实时动态性能需求，而针对新型飞秒激光跟踪仪的动态误差研究未见相关报道。本课题旨在深入分析飞秒光频梳测距误差、动态测角误差的形成机理，通过建立动态误差物理和数学模型，提出动态误差补偿修正方法。在此基础上将测距、测角误差进行综合考虑，结合测量任务提出飞秒激光跟踪仪测量不确定度表征方法，为飞秒光频梳测距提供理论支持，并为自主研制的飞秒激光跟踪仪动态测量精度提供技术保障。

本课题研究了双飞秒激光测距精度与不确定度，将双飞秒激光测距精度误差分解为空气折射率引起的不确定度、双飞秒重频锁定不确定度、重频稳定性不确定度、飞行时间不确定度等，其中飞行时间不确定度包括重频差不确定度、相位噪声不确定度、CEO噪声不确定度等。实验测距结果为0.5ppm，基于不确定度理论分析的测距结果0.43 ppm，理论分析与实验结果基本吻合，为飞秒光频梳测距提供了理论支持。.研究了激光跟踪仪角度误差标定的不确定度，影响因素包括棱体检定误差引入的不确定度、自准直仪示值误差引入的不确定度、误差标定装置引入的不确定度等，最终得到合成标准不确定度和有效自由度。研究了测角误差实时补偿技术，分析比较了四种实时补偿算法：线性函数、三次样条函数、多项式函数以及谐波函数，对这四种方法补偿后的平均值、标准差、峰峰值等进行了横向比较，得出结论为谐波函数方法最优。将谐波补偿模型等算法程序加入到激光跟踪仪软件模块中。编写了VC误差补偿函数，并封装成子函数，供飞秒跟踪仪测量软件的角度测量模块调用，达到角度值能实时补偿的目的。.综上，通过研究飞秒激光跟踪测距与测距不确定度及动态补偿技术，提出了飞秒激光跟踪仪测量不确定度表征方法，为飞秒光频梳测距提供了理论支持，并为自主研制的飞秒激光跟踪仪动态测量精度提供了技术保障。