【作者】 郭兰申；

【导师】 李世杰； 刘更谦；

【作者基本信息】 河北工业大学 ， 机械制造及其自动化， 2000， 硕士

【摘要】 随着计算机软硬件及信息处理技术的发展，图形扫描及识别技术输入方法在CAPP系统中得到日益广泛的应用。本文详细研究了CAPP系统零件信息的描述与输入方法，提出了基于特征单元的零件信息描述方法，力求做到零件信息描述的全面方便。 本文探索了适当的数字图像预处理方法，研究并提出了机械零件数字图像特征信息的提取方法和实现算法。神经网络用于模式识别的实质是模式特征空间的变换。故特征向量信息的构成是利用神经网络分类器的基础。本文在研究提取特征信息方法时，兼顾了零件整体轮廓和内部结构特征的提取，并为以后开发智能的集成系统奠定了基础。 在识别过程中，对神经网络的BP算法提供了一种改进算法，并用于机械零件图像的识别，实验数据证明取得了较好的分类识别效果。利用神经网络模拟人类的形象思维的特点，兼有学习、记忆的功能，将相似类零件进行更详细的分类，定位；然后根据特征的描述方法，检索生成工艺文件。根据零件的分类结果CAPP系统检索出该零件族的典型工艺，从而完成零件与加工工艺的对照。更多还原

【Abstract】 With the development of the scanning and recognition technologies, it is very common to adopt these technologies. The methods about the description and input of mechanical parts in the Computer Aided Process Planning (CAPP) system are discussed in the paper. So the method for describing mechanical parts which is based on the feature unit is proposed in order that the description for mechanical parts is convenient and completely.Not only the proper method for the preprocessing of image is researched in the paper, but also the algorithms of extraction and calculation about the image features of mechanical parts are proposed. The essence of the neural network utilization for pattern recognition is the changing of the pattern space. Therefore, the constitutions of feature vector are the basis of the using of neural network classifier. The paper considers the whole profile and the internal structure feature, and will be the splendid basis for the intelligent integrated systems.During the process of recognition, a improved algorithm for neural network in Back梡ropagation learning algorithm is provided, and the algorithm is applied to mechanical part images recognition .The result shows that the testing is very good. With the characteristics of the neural network imitating human thinking in images, the functions of studied and memories, the detail classification and location, and then using the method of feature description, the file of technologies can be obtained searchingly. According to the result of parts classification, the system of CAPP can search the characteristic technologies of the part group, and then finish the comparison between the parts and the process technologies.更多还原