【作者】 李瑞君；

【导师】 范光照；

【作者基本信息】 合肥工业大学 ， 测试计量技术及仪器， 2013， 博士

【摘要】 针对微小结构和器件对大量程、高精度坐标测量方法和装置的需求,本论文研制了一套可用于微纳米三坐标测量机的接触扫描探头系统。该探头可分为弹性机构和三维传感器两部分：弹性机构由测球、测杆、悬浮片、平面反射镜、弹性元件、固定装置等组成,可将测球在三维方向上的位移转换成平面反射镜的转角或位移；三维传感器负责感测平面反射镜的角度和位移变化。论文完成了以下主要工作：(1)提出了由微型迈克尔逊干涉仪和基于DVD光学读取头的二维角度传感器组成的三维传感器；拓展了DVD光学读取头的角度感测范围：研制了体积小且对称性好的三维探头。在此基础上,去掉DVD光学读取头的具体形态,分别设计制作了基于迈克尔逊干涉仪和自准直仪的共光路和并联光路的三维传感器。在并联光路情况下,通过在迈克尔逊干涉仪与对应平面反射镜之间增加聚焦透镜的方式,提高了迈克尔逊干涉仪的抗偏角能力。(2)设计了基于簧线的等张力弹性机构和基于“Z”字形以及“V”字形铍青铜簧片的弹性机构,建立了三种弹性机构的刚度模型。确定了测球与被测面之间允许的最大接触力,分别对三种弹性机构进行了优化设计并得出了最佳结构参数,通过ANSYS仿真和实验验证两种方式验证了理论分析结果的正确性。(3)构建了不同的实验系统,对加工、组装、调试好的探头,分别进行了测力、分辨力、稳定性、量程和重复性等方面的测试。测试结果表明：探头的测力梯度小于1mN/μm,分辨力为1nm,量程为±20μm20μm×20μm,重复性精度小于30nm；环境温度变化是引起探头信号漂移的主要原因,探头中机械部件和结构对温度的敏感度远远超过光电部分,恒温环境下探头1小时内的漂移量小于30nm。(4)分析了探头三轴输出信号间相互耦合的原因,提出了三种不同的解耦模型,搭建了基于PI纳米定位平台的校正系统并获得了原始的校正数据,利用校正数据分别求出了基于多元线性回归三维模型和基于泰勒展开式三维模型中的解耦参数,经对比前者的精度更高。通过对标准量块的平面度、厚度以及一个有效直径约为6mm的凸透镜的测量,验证了探头的有效性。分析了探头的误差,并给出了修正或减小的办法。更多还原

【Abstract】 In this research a novel scanning probe has been developed, with micron range and nanometer resolution. This probe can be equipped in a3D micro/nano measuring system for microstructure measurement. This scanning probe includes an elastic mechanism, composed by a ball-tip, a stylus, a floating plate, reflective mirrors, elastic components and the housing structure, transforming the3D motion of the tip-ball into the angular and linear displacement of the reflective mirrors, which can be detected by an embedded3D sensor. The main tasks of this research are listed as below:1. A3D sensor has been proposed by integrating a micro Michelson interferometer and a DVD pickup head for linear and angular measurement respectively. The angle measuring range of the DVD pickup head has been effectively increased. An elastic-component-based probe structure featured by small size and good symmetry has been designed. Then, instead of the DVD pickup head with a micro auto-collimator which shares the same laser diode with the micro Michelson interferometer, a reformed3D sensor based on the micro auto-collimator and the micro Michelson interferometer has been designed. Additionally, an optional structure of the micro Michelson interferometer and micro auto-collimator with parallel optical path was also developed to achieve better alignment tolerance by introducing a lens beside the reflective mirror.2. Three elastic structures with equal-strain based on elastic strings, Z-shaped and V-shaped beryllium bronze plate springs have been designed and the rigidities have been modeled respectively. The maximum permitted contact forces in scanning measurement have been calculated aiming at the typical materials both the specimen and the ball tip. Each structure has been optimized and the proper parameters have been obtained. The optimized designs have been testified by both ANSYS simulation and practical experiments.3. After the fabrication, installation and testing of the probes are completed; different experimental systems were set up to calibrate the contacting force, resolution, stability, measuring range and repeatability. Experimental data show that the probe has the contacting force gradient within1mN/μm, resolution of1nm, measuring range of±20μm x±20μm x20μm and the repeatability accuracy within30nm. It’s found that the temperature variation contributes most to the reading drift. Compared with the optoelectronic system, the mechanic structure is much more sensitive to the temperature variation. In a constant temperature space the reading drift of the probe is less than30nm for the duration of one hour.4. The coupling of three axes has been analyzed and three different mathematic models have been proposed for decoupling. A PI nanopositioning stage was employed to set up the calibration system, with which the original measurement data table was acquired. Then two mathematic models, based on multiple linear regression and Taylor expansion respectively, were configured with the original measurement data to determine the decoupling parameters. The former was found to have higher accuracy. The working performance of the probe has been testified by measuring the flatness and thickness of a standard gauge block and the diameter of a convex lens. Besides, the error source of the probe was analyzed and the methods to improve the measuring accuracy were proposed.更多还原