长导轨五自由度测量中直线度精度提升方法与优化设计  

Accuracy improvement method and optimal design of straightness in five-degree-of-freedom measurement of long guide

作　　者：张聪[1] 刘文正 段发阶[1] 傅骁[1] 王新星 ZHANG Cong;LIU Wenzheng;DUAN Fajie;FU Xiao;WANG Xinxing(State Key Laboratory of Precision Measuring Technology&Instruments,Tianjin University,Tianjin 300072,China)

机构地区：[1]天津大学精密测试技术及仪器国家重点实验室,天津300072

出　　处：《光学精密工程》2022年第20期2467-2478,共12页Optics and Precision Engineering

基　　金：国家重点研发计划项目(No.2020YFB2010800);国家自然科学基金项目(No.61905175,No.61971307);国家重点实验室探索课题项目(No.Pilt2103);霍英东教育基金会资助项目(No.171055);青年人才托举工程项目(No.2021QNRC001);广东省重点研发计划项目(No.2020B0404030001);国防科技重点实验室基金项目(No.6142212210304)。

摘　　要：为了提升长导轨五自由度测量中直线度测量精度,对五自由度测量装置中直线度测量单元的测量光路、误差模型和标定方法等进行研究。长距离测量时基准光束角度漂移会造成严重的直线度误差,光路中采用了望远物镜结构测量角度漂移,相比于单透镜,这种可以在有限空间内增加焦距,使得组合焦距大于机械尺寸,从而提高测量精度,并通过补偿提高测量稳定性;分析了角度串扰引入的误差,并结合装置中的角度测量值建立了补偿模型;采用四象限探测器作为直线度测量传感器,为解决传感器测量非线性随量程变大而加剧以及测量灵敏度随长导轨移动非线性变化的问题,提出了一种多项式拟合与三次样条插值拟合相结合的分区间标定方法。试验结果表明:在5 m的测量距离以及±400μm的量程内,与激光干涉仪测量结果对比,误差标准差小于0.3μm,3 h内漂移小于±0.5μm。满足长导轨直线度测量对大量程、高精度、高稳定性的要求。To improve the straightness accuracy during the five-degree-of-freedom measurement(5DOFM)of long guide,the measurement light path,error model,and calibration method of the straightness measurement unit in the 5DOFM device were examined.During long distance measurement,the angle drift of the reference beam causes severe straightness error.Accordingly,a telescopic objective lens structure was adopted to measure the angle drift in the optical path.Compared with a single lens,the focal length can be increased in a limited space,such that the combined focal length is larger than the mechanical size,thereby improving the measurement accuracy,and compensating for the angle drift to improve the measurement stability.Additionally,the error introduced by angle crosstalk was analyzed,and a compensation model was established based on the angle measurement value in the device.A four-quadrant detector was used as the straightness measurement sensor.To solve the problems that the nonlinearity of the sensor increases as the range increases,and the sensitivity changes nonlinearly with the movement of the long guide,an interval calibration method combining polynomial fitting and cubic spline interpolation fitting was proposed.The experimental results showed that within the 5-m measurement distance and±400-μm range,the error standard deviation was less than 0.3μm compared with the measurement results of the laser interferometer,and the drift was less than±0.5μm within 3 h.Thus,the straightness measurement unit meets the requirements of large range,high precision,and high stability of long guide straightness measurement.

关 键 词：光束漂移 角度串扰 四象限探测器 长距离 多项式拟合 三次样条插值拟合 

分 类 号：TB921[一般工业技术—计量学] TH741[机械工程—测试计量技术及仪器]