【作者】 苏东风；

【导师】 续志军；

【作者基本信息】 中国科学院研究生院（长春光学精密机械与物理研究所） ， 机械电子工程， 2011， 博士

【摘要】 本文论述的测试转台是标定测绘相机用的高精度、高稳定性、大尺寸、大载荷的复杂精密机电设备，为了实现精确定位我们研制了高精度光栅测角系统。本文以实际的工程项目为基础，对光棚测角系统的关键技术包括光机结构系统、电子学、精度分析和检测、误差补偿等方面进行了深入研究和探i、J。论文论述了光栅测角系统的基础理论、光栅信号主要质量指标以及对光栅信号质量产生影响的因素、光栅信号质量的检定方法，对测角系统的误差进行了理论分配来指导系统设计，为了有效提高测角精度并降低成本，研究了误差的软件补偿方法。论文分析了光机结构系统的关键技术：轴系采用高精度、高稳定性的密珠轴系；主光栅采用大直径薄光栅；采用指示光栅的多缝读数配合多头读数，减少光栅分度误差的长、中、短周期误差；采用四读数头全数字量相加技术，减小了光栅盘的偏心误差，降低了对装调的苛刻要求。论文对测角系统的轴系晃动误差、光栅盘分度误差、细分误差等进行了分析，并对轴系晃动误差和光栅盘分度误差进行了检测。论文分析了测角系统电子学的关键技术：选用性能稳定，特性一致的光电接收元件；采用相位补偿电路减少相位漂移；采用了差分放大电路减少直流分量误差；采用幅值调整电路保证了细分信号的等幅性，由于采取多种技术手段，保证了精码信号的正交性。设计了均匀性、准直性、稳定性好的照明系统，保证角度信号的高质量。采用改进的BP算法对测角系统的测角误差进行了补偿，有效的提闻了系统的测角精度。采用直接比较法和排列全组合法实测了测角系统的精度。实测结果表明测角系统精度达到设计指标，满足使用要求。本论文的完成结合了测绘相机标定转台的实际工程项目，同时也是对该工程项目的总结。主要创新点如下：(1)在光机结构系统设计中，提出了利用指示光栅的多缝读数配合多头读数消除主光栅的长、中、短周期误差；(2)在复制大直径薄光栅盘时，推导出了支撑板变形与厚度的理论关系公式，为成功研制高精度的大直径薄光栅提供了理论基础；(3)测角系统的传统软件误差补偿方法多是基于数值分析或误差修正表法，本文将BP神经网络及其改进算法应用于测角系统的误差补偿，有效的提高测角系统的精度，丰富了测角系统误差补偿的方法。本文的研究内容为研制大型高精度转台光栅测角系统提供了理论依据和工程经验，具有重大的工程意义。更多还原

【Abstract】 The testing turntable in the dissertation is a kind of high positioning accuracyand stability,large scale,great loading capacity,complex and precisionmechano-electronic equipment used for calibrating mapping camera. To locate withprecision we develop a kind of high precision grating angle measuring system.Thedissertation based on practical engineering project thoroughly researches the keytechniques of grating angle measuring system.The key techniques include the keydesign of optical and mechanical structure system, the key design of electronics,theanalysis and testing of error,the compensation of error etc.The dissertation dissertates the theory of grating angle measuring system basedon grating MoireFringe technique,the quality parameter and affecting factors ofgrating signal,the gauging methods of grating signal quality. The precision of theangle measuring system is distributed theoretically to directing the design.Forimproving the precision and reducing the cost effectively the error compensationmethods using software is researched.The dissertation dissertates the key techniques of optical and mechanicalstructure system. High accuracy and high stability dense ball bearing shatfing isdesigned. The primary grating is a kind of thin and big diameter grating. Fourreading heads and multilineal index gratings are used to reduce the period error ofgrating. The application of digital addition technology reduces the eccentricity errorof the primary grating and the difficulty of installation.The dissertation analyses the error source of the angle measuring system andtests the shafting movement error and grating dividing error.The dissertation analyses the key techniques of electronical design. The detecting components that have stability capability and identical characteristic ischoosed.To decreasing phase excursion correcting circuits of signals phase are used.To reduce zero offsets error the difference amplifying circuits are used. To reduceunequal amplitude error amplitude adjusting circuits are used. Because manytechnical mehods are used,the quartering of signals is ensured.The illuminationsystem that has symmetrical,parallel and stability characteristic is designed to ensurethe high quality of signals. The dissertation uses improved BP algorithm to reducethe angle measuring error and the precision of angle measuring system is improvedsignificantly.The precision is tested by the directly comparing method,permutation and entirecombination method.The result shows that the precision can achieve the target of thedesign and satisfy requirements.The dissertation is completed by combining practical engineering andsummarizes the project at the same time.The primary innovation points of thedissertation are as follows:(l)In the design of optical and mechanical structure system, The method ofusing multilineal index gratings and four reading heads is put forword to reduce theperiod error of primary grating;(2)The formula between distortion and thickness of supporting board isdeduced when duplicating thin and big diameter grating,which provides basic theorypledge to develop high precision grating.(3)Thetradition software compensation method of angle measuring system isbased on numerical value analysis mehod or error correct table method.Thedissertation uses BP neural network and improved BP algorithm to reduce the anglemeasuring error.The precision of angle measuring system is improvedsignificantly.The method of this dissetration is aflfuent in the method ofcompensation error of angle measuring system.The research of this dissertation provides pratical experience and theoreticalbasis for the developing of turntable grating angle measuring system,which isprominent in practical and theoretical significance.更多还原