【作者】 刘晓如；

【导师】 陈良益；

【作者基本信息】 中国科学院研究生院（西安光学精密机械研究所） ， 光学工程， 2008， 硕士

【摘要】 同轴度测量也称轴对中技术,主要用于旋转机械两联结轴轴线的平行偏差(平偏)和倾斜偏差(角偏)的测量。在机械加工、电力、石化、航空等行业的众多设备上都离不开使用旋转机械,这些机械轴系的同轴度对设备正常运行有着至关重要的影响。因此在设备安装、日常维护和维修中都要进行同轴度测量。传统的人工测量法和光电测量法效率低、人为误差大、自动化程度低,难以满足不断发展的测量需求。计算机视觉检测技术是以现代光学为基础,融光电子学、计算机图像学、信息处理、计算机视觉等科学技术为一体的现代检测技术,具有非接触、全视场、速度快、精度高等优点,在军工、机械、电子、农业、医学等领域得到了广泛的应用。将计算机视觉检测技术的相关原理与算法用于同轴度测量系统,可以有效提高系统的测量效率和测量精度。本文对同轴度测量所涉及的技术领域及其在国内外的发展状况进行了调查和分析,完整介绍了运用激光进行同轴度测量的几种技术原理。提出了将计算机视觉检测技术的先进算法和原理用于同轴度测量系统的思路,概述了计算机视觉检测技术的国内外研究现状。论文描述了同轴度测量系统的测量原理,推导了测量角偏和位偏的计算公式,在此基础上介绍了系统的软硬件组成模块。设计了视频采集和多线程同步处理的方法和流程。数字图像处理是计算机视觉检测的核心内容,对系统的测量精度和测量效率具有决定性作用。本文着重论述了图像处理中的滤波、阈值分割和边缘检测三方面的内容,深入分析了几种光斑中心检测的算法,建立了一套综合图像处理过程,即自适应简单去噪—峰谷阈值分割光斑特征区块粗定位—数学形态学运算,进一步提高查找区块精度—灰度质心法光斑中心计算。这些措施有效地保证了中心定位的稳定性和测量精度。论文对整个系统测量结果进行了实验验证,并给出了测量结果的精度和重复性分析。实验结果表明,本论文所述的同轴度测量系统精度高、重复特性好。更多还原

【Abstract】 Coaxiality measurement technology, which is also named axis centring technology, is mainly used to measure position deviations and angle deviations of rotarys’ coupler. Rotarys have been widely applied in many fields such as machining, power generator, aerial equipment detecting. Whether the set of axes in these fields is centered has great influence on equipments’ normal working. So coaxiality must be measured not only in the process of equipment installation but also in the process of current repair. Manual method and photoelectric method have some shortcomings, such as inefficiency, big man-made error and low-level automatization, so conventional methods do not meet the requirement in measurement of coaxiality. Computer vision inspection is a new technology based on modern optics, which syncretizes optical electronics, computer image, information processing, and computer vision. It has many advantages, such as non-contact, big field, high efficiency and high precision. It also has the ability of on-line inspection, real-time analysis and control. It is widely used in military industry, mechanism, electronics, agriculture, medicine and so on. Some principles and algorithms of computer vision inspection can be used to improve the efficiency and accuracy in measure system of coaxiality.Developing process in the field of coaxiality measurement was been researched and analyzed, and several methods which employed laser to measure coaxiality were introduced. The idea is put forward that the principles and algorithms used in computer vision inspection will be adopted in coaxiality measuring system. The situation and trend in development of computer vision inspection have been summarized.This paper described the measuring principle of the coaxial measurement system. A formula used to compute position deviations and angle deviations was.given This system is consisted of the hardware and software. A algorithm routine of video collection and multi-threaded sync were schemed out.Image processing is the kernel of computer vision inspection, and has great effect on accuracy and efficiency. In this paper, the basic concept of digital image is introduced, and some methods of image processing, such as image filter, image segmentation and edge detection, are discussed in detail. Based on basic image processing methods, the special image processing method, which include denoising through Wiener, segmentation through threshold, center calculating through improved method of computation of center of mass base on gray level, is designed in this measure system.The accuracy of coaxiality measurement system was been theoretical analyzed and experimental verified. The result indicates the system has excellent accuracy and repeatability.更多还原