【作者】 刘泊；

【导师】 郭建英；

【作者基本信息】 哈尔滨理工大学 ， 精密仪器及机械， 2013， 博士

【摘要】 在生产加工过程中，随着光学元件、微机械以及其它各种零件精加工表面的不断出现，对零件表面的性能要求越来越高。相应地，对零件表面微观结构和状态的测量及评定也提出了更高的要求。传统的二维测量和评定虽然测量手段和评定方法比较完善,但二维测量和评定不能全面真实地反映出表面的微观状态，也不能和表面功能建立起很好的联系。而表面三维微观轮廓和三维粗糙度参数由于能更全面、更真实地反映零件表面的特征及衡量表面的质量而越来越受到重视，因此表面三维微观轮廓的测量及三维粗糙度的评定的研究显得非常重要。在分析和总结国内外非接触表面三维微观轮廓测量技术研究的基础上，论述了表面三维微观轮廓测量技术主要采用光学测量法，其显著特点是将传统光学计量技术与信息光学和信息处理技术相结合，来实现表面三维微观轮廓的测量。目前，已经研究出多种光学测量方法，而白光相移干涉法以其测量范围大、调制方便、实时快速、高精度及全场自动测量等优点，被广泛的应用到表面三维微观轮廓测量中。然而该技术仍然存在着白光相移干涉中零级条纹相位偏移、相移误差引起轮廓解调误差等问题。本文围绕三维表面微观轮廓测量及评定这一主题，针对白光相移干涉三维微观表面检测系统中存在的不足，以白光相移干涉测量技术为基础，采用白光为干涉光源，以迈克尔逊干涉仪为主体，由相移微位移驱动系统、CCD摄像头、图像采集卡、计算机等构成测量系统，对表面三维微观轮廓测量技术展开了较为全面的理论与实验研究，主要创新性工作和研究内容包括：1.通过对目前三维微观轮廓解调算法的研究与分析，提出了数字滤波和二次曲线拟合的算法，解决了在白光相移干涉中零级条纹相位偏移的问题。与其它解调算法比较，该算法可以有效地提高白光干涉图像中零级条纹位置的识别精度；2.提出了对相移微位移驱动器采用PID闭环控制与蠕变补偿控制相结合的复合控制方法，解决了由于相移误差带来的轮廓解调误差。该方法利用光学杠杆和PSD构成微位移检测回路，将相移微位移动器的微位移量反馈至控制系统，建立PID闭环控制。根据压电陶瓷蠕变特性对测量过程的影响，建立了“电压蠕变”补偿模型，实现了基于PID闭环控制与蠕变补偿控制相结合的复合控制方法，使相移得到精确控制，提高了表面三维微观轮廓的测量精度。3.根据所提出的表面粗糙度测量中高斯滤波器的B样条函数实现方法，通过对变分原则引入约束条件，并结合小尺度高斯滤波器级联的特性，得出了一维高斯滤波的逼近滤波器。将一维高斯滤波器推广到二维情形，建立了表面粗糙度测量的高斯滤波基准面。通过仿真实验验证了该滤波器能够满足对滤波器高精度、高效率的要求。4.开发了表面三维微观轮廓测量软件系统。对表面三维微观轮廓测量系统进行了标定，给出了测量系统的测量精度，通过对粗糙度标准样块测量得到了测量结果。实验结果表明表面三维微观轮廓测量系统的测量误差为0.003μm，重复性测量误差为0.002μm。更多还原

【Abstract】 With the rapid development of optical elements, such as MEMS, and othersurface finishing techniques, demand for surface performance of parts becomesincreasingly high. As a result, greater requirements have been put on themeasurement and evaluation of microstructure and characterization. Althrough thetraditional2D suface measurement and evaluation methods have been mature, it cannot effectively reflect the microstate of part surface and can not establish goodconnection with surface function. As the3D microscopic profile and its roughnessparameters can represent characteristics and qualities of part surface effectively, it isvery important to carry out relative research on them.After analyzing and summarizing the measurement technology of non-contactsurface3D microscopic profile, state-of-the-art technologies of3D microscopicprofile measurement were introduced in this paper. The advantages are to combinetraditional optical measurement methodologies with information optics and signalprocessing technology to measure3D microscopic profile. Until now, white-lightphase-shifting interferometer outperforms other proposed methods with the merits oflarge measuring range, modulation convenience, fastness and real time, highaccuracy and whole field automatic measurement. It has been widely applied tomeasure surface3D microscopic profile. But this technology still exists someproblems, including zero-order fringe phase deviation, profile demodulation errorcaused by phase shift.Aiming at the subject of surface3D microscopic profile measurement, thisthesis focused on the shortcomings of3D microscopic surface detection system withthe help of white-light phase-shifting interferometer technology to solve relatedproblems. According to the principle of white-light phase-shifting interferometer,white light was chosen as interference source and Michelson interferometer was usedin experiments. The measurement system consists of phase shift micro-displacement driving device, CCD camera, image acquisition card, computer and so on.Comprehensive theoretical and experimental research was conducted and the maininnovative contributions and research contents are as follows:1. By analyzing the phase demodulation algorithm, a combination algorithm ofthe digital filter and quadratic curve fitting was proposed in this paper, which cansolve the problem of zero-order fringe phase deviation during white-light phase-shifting interferometer. Compared with other demodulation methods, the proposedmethod can improve the recognizing precision of zero-order fringe position in whitelight interferometer images.2. To reduce the profile demodulation error caused by the phase shift, thecompensation control method was proposed by combining PID close-loop controland creep compensation control. The micro displacement detection circuit includesthe optical leverage and PSD, by which the micro displacement in phase shift wassent back to the control system to achieve closed-loop control. After considering theinfluence of creep properties of piezoelectric ceramics to the measurement process,voltage creep compensation model was established. This model can realizecompensation control using PID close-loop control and creep compensation control,which can control phase shift accurately and improve the measurement precision of3D surface microscopic profile.3. Based on the B spline function of Gaussian filter in the process of surfaceroughness measurement,1D Gaussian approximation filter was designed byintroducing the constraint conditions of variation principles and combining with thecascade characteristics of small scale Gaussian filters. After that, the1D Gaussianfilter was extended to two dimension so that the Gaussian filter base surface wasestatlished to measure roughness. Simulation experiments showed that this filter canachieve high precision and efficiency.4. The application software of surface3D microscopic profile measurement wasdeveloped. After calibrating the surface3D profile measuring system, measurementaccuracy was obtained by measuring the roughness of standard blocks. Experimentsshowed that the measurement error of surface3D profile measuring system is0.003μm and the repeatability of measurement error is0.002μm.更多还原