【作者】 张进；

【导师】 叶声华； 王仲；

【作者基本信息】 天津大学 ， 测试计量技术及仪器， 2010， 博士

【摘要】 随着计算机技术的飞速发展,影像测量技术凭借其非接触、高精度等优势已获得了广泛的应用。近年来由于工业工艺水平的不断进步,高精度微型零件的数量呈指数增长。然而,现有的影像测量仪受精度与视场矛盾的制约,测量效率低下,难以满足高精度、高效率的测量需求。本文对高精度影像测量系统中的关键技术进行了研究,包括硬件系统的搭建与调整、高精度的边缘定位技术、系统标定以及图像超分辨率重建技术等。以手表中精度最高的零件之一——擒纵轮为测量对象,完成了“擒纵轮视觉检测仪”,实现了不同规格擒纵轮高精度、高效率的测量,相对测量精度优于1/2000,并完成了工业现场的调试和验收。具体的工作和创新点主要包括:1.以擒纵轮为测量对象,完成了高精度影像测量系统。主要包括:确定基于完整成像的测量模式;采用自行设计的物方远心光路,并在设计中将擒纵轮关键尺寸所处的环带区域(靠近视场边缘的部分)畸变矫正至最小;完成了照明设计。2.对系统光轴与物面的垂直度和物面的对焦精度的高精度调节进行了研究。分别提出了基于图像区域清晰度的系统光轴垂直度评价方法和基于图像插值的清晰度评价方法,通过实验验证了方法的有效性,并实现了“擒纵轮视觉检测仪”中系统光轴与物面的垂直度和物面对焦精度的高精度调节。3.研究了图像边缘的高精度定位技术。包括像素级的边缘提取,轮廓跟踪技术和亚像素级的边缘定位技术。提出了基于模板相关的亚像素定位算法,对不同类型的边缘建立不同的边缘模板,利用该模板和实际边缘进行相关运算,找出最佳的相关位置,从而实现边缘点亚像素级精度的定位。4.完成了高精度的系统标定以及擒纵轮特征参数的计算和软件设计。实现了多种规格擒纵轮的11类参数的高精度、高效率测量,并完成了“擒纵轮视觉检测仪”的现场调试,通过测试验收,可靠、稳定的运行在工业现场。5.研究了基于序列图像的超分辨率重建技术以提升原始图像的分辨率,从而提升测量精度。针对当前基于精确微位移的序列图像超分辨率重建技术中,精确微位移难以获取的难题,提出了基于随机微位移的超分辨率重建技术,并用于影像测量,提升了测量精度,设计实验证明了该方法的有效性。更多还原

【Abstract】 With the development of computer techniques, image measuring techniques are widely used in the industry, by right of the advantages such as non-contact, high accuracy and so on. The number of high-precision subminiature accessory applied in the industry is exponential increasing year by year, due to the constant progress of industrial level. However, the existing image measuring instrument is difficult to meet the measurement demand of high accuracy and efficiency, for the measurement efficiency is low which is restricted by the contradiction between precision and field range. This thesis is studied on the key technology of high accuracy image measurement system, including the building and accurate adjustment of the hardware system, edge location technology of high accurate, system calibration, image super-resolution reconstruction and so on. The Vision Inspection Instrument for Escape Wheel(VIIEW) was built for the measurement of escape wheel which was one of the highest precision parts in the horological industry, and has realized the measurement of different specifications of escape wheel with more precise and efficient. Besides,The VIIEW, of wich the relative accuracy is better than 1/2000, also finished the debugging and acceptance in the industrial field. The main contributions and innovative points of the thesis include:1. A high accuracy image measurement system for the precise measurement of the escape wheel is designed and built. It mainly includes: determined the measurement mode based on entire imaging; adopted the self-designed object telecentric lens, which make the distortion of annular area containing the key parameters of the escape wheel(area close to the field margin) minimum; finished the designing of lighting system.2. The highly accurate adjustment of the verticality between optical axis and object plane and the focusing of object plane are studied. One kind of image definition criterion algorithm which is based on the image interpolation and the algorithm of detecting verticality based on regional image definition are proposed respectively. According to experiments, both of the methods are effective, and realized the highly accurate adjustment in the VIIEW.3. The highly accurate location technology of image edge is studied, including edge detection of pixel level, contour tracking technique and edge location of sub-pixel level. A sub-pixel location algorithm based on matching template is proposed. By building relevant matching template considering the edge of different type, carrying correlation operation between matching template and the image edge, and finding the position of most correlation, high accurate edge location of sub-pixel is achieved.4. System calibration with high precision, calculation of escape wheel’s parameters and software designing are completed. Realizing the high precision and greater efficiency measurement of escape wheel’s 11 parameters of many types, the VIIEW can work in the industrial field reliably and stablely after finishing field debugging and obtaining acceptance test.5. The reconstruction technique of super-resolution based on image sequence is studied to improve the resolution of the original image, which helps to improve the measuring precision. In order to solve the problem that the micro-displacement of high accuracy is difficult to realize in the reconstruction of super-resolution based on precise micro-displacement, the reconstruction technique of super-resolution based on random micro-displacement is proposed. This method can promote the measuring precision when using in the image measurement which proves to be effective by designed experiment.更多还原