【作者】 夏瑞雪；

【导师】 卢荣胜；

【作者基本信息】 合肥工业大学 ， 光电信息工程， 2012， 博士

【摘要】 数控机床是先进制造过程中的核心设备。在加工过程中,有着大量的检测任务需要完成,包括夹具和零件的装卡、找正、零件编程原点的测定、首件零件的检测、工序间检测和加工完成检测等。因此,开展面向数控机床的在位测量技术的研究具有重要的学术价值和现实意义,将是实现测量与制造无缝链接的重要纽带,受到国内外的广泛关注。影像在位测量技术是要将影像测量仪搬至数控机床,凭借影像测量的优势,实现非接触、高精度和高效率的几何量在位测量,以弥补基于接触式触发测头的在位测量的不足。本文的研究目的是为组建基于影像测头的数控机床影像在位测量系统做前期预演,以自行研制的一套影像测量实验系统作为工作平台,围绕其中的关键问题展开系统深入的研究,主要包括基于图像对焦的三维影像测量、计算机辅助测量规划(CAIP)、基于图像/CAD模型的全屏目标牵引、图像边缘检测和几何量测量等。本文主要的研究工作和创新点如下：1.研制了一套影像测量实验系统,作为本文开展相关研究的实验和验证平台,其主要由三维工作台、影像测头和显微视觉测量软件组成。2.以自动对焦技术中的图像对焦法为对象,研究基于图像对焦的三维影像测量。其中,本文结合步进电机的特性,提出了一种基于不等步距的粗细结合的对焦搜索策略,且通过实验研究了被测工件的表面粗糙度对测量精度所造成的影响,并尝试将误差分离技术应用于对焦测高。3.针对数控机床影像在位测量系统,初步开发了一套面向影像测量的计算机辅助测量规划系统(V-CAIP系统),主要由测量元素提取和识别、采样策略规划、测量路径规划、测量代码生成和测量过程校验五大功能模块组成。4.由于影像测头的视场较小,无法对被测物体的全貌加以观察,故本文以“点哪、走哪、测哪”为指导思想,开发了基于鼠标点击的全屏目标牵引功能,具体划分为图像法和CAD模型法。5.以工件的显微图像为对象,研究基于数学形态学法和径向基函数法相结合的图像边缘检测方法,并针对影像测量,研究面向其的几何量测量方法。更多还原

【Abstract】 Computer numerical control (CNC) milling machine, which is the core equipment in the advanced manufacturing process, has a large number of tasks to be inspected, including clamp and part fixed, alignment, NC programming origin measuring, first part inspection, inspection between the process sequences, finished part inspection, and so on. Therefore, carrying out the study of the on-machine measurement technology of CNC milling machines plays an important part in both the academic and practical application. This technology will be the important link to realize seamless connection between measurement and manufacture, and has been widespread concern at home and abroad.Image on-machine measurement technology is considered as moving image measuring instrument to CNC milling machines, and takes the advantages of image measurement to realize the non-contact, high accuracy and high efficiency geometric on-machine measurement, which makes up the shortage of the touch trigger probe. This study aims to pre-preview for establishing an image on-machine measurement system of CNC milling machines based on image probe. The key technologies of image on-machine measurement, including the building and accurate adjustment of the hardware system, the three-dimensional image measurement based on image focusing method, the computer-aided inspection planning, the full-screen target guidance based on image or CAD model, the image edge detection and the geometric measurement, are studied in depth based on the developed image on-machine measurement experimental system.1. An experimental system for image measurement is designed and developed, which is used to carry out the key research. The developed system mainly includes:three-dimensional stage, image probe, microscopic vision measurement software.2. The three-dimensional image measurement is studied based on the image focusing method of auto-focusing technology. Focusing search strategy on the basis of unequal step length is proposed. The relationship of measurement accuracy and surface roughness of the workpiece is discussed in accordance with the experimental results. In addition, the error separation technology is used for improving the accuracy of the height measurement.3. A computer-aided inspection planning (CAIP) system for image measurement is developed in accordance with the image on-machine measurement system. The function modules of the developed system are composed of the inspection information extraction, the sampling strategy, the inspection path planning, the inspection codes generation and the inspection procedure verification.4. Since the field of view of the image probe is limited and the full view of the measured object can not be observed, the full-screen target tracking function based on the mouse-click is developed. The function is mainly divided into the image method and the CAD model method, and can realize that what you see is what you get.5. The image edge detection method based on the mathematical morphology (MM) and the radial basis function (RDF) for the microscope image of the workpiece is studied, and the geometric method for image measurement is also investigated.更多还原