【作者】 张洪波；

【导师】 刘日良； 张承瑞；

【作者基本信息】 山东大学 ， 机械设计及理论， 2011， 硕士

【摘要】 在高生产率、高产品质量和低生产成本的大趋势下,数控加工成为目前制造业中普遍使用的先进制造技术,而车削又是最主要的制造方式之一。当前数控系统所采用的数据接口标准是基于G代码(IS06983)的,基于G代码的加工信息是单向的,数控系统只能按照加工程序控制数控机床的运动,加工中出现的问题不能直接反馈到设计阶段,很难支持先进制造模式和实现数控系统的智能化。为了提高CAD/CAPP/CAM/CNC之间的数据交互能力以及克服IS06983标准的缺点,1997年,欧、美等工业发达国家提出了一种新的数控接口标准STEP-NC。STEP-NC标准是STEP标准向数控领域的拓展,目的是建立起一条贯穿产品设计与制造过程的信息高速公路。STEP-NC标准第12部分ISO14649-12对基于STEP-NC的数控车削的数据模型以及相关技术进行了详细的说明。随着制造系统向集成化、智能化的方向发展,基于STEP-NC的数控车削加工技术必将有着广阔的发展前景。本文是基于STEP-NC的智能化车削数控系统开发的一部分,在课题组前面工作的基础上改善了STEP-NC信息提取方法,着重讨论了车削特征的加工工艺参数优化,并研究了工艺规划和刀具路径规划,并根据研究中拟采用的控制平台生成相应的数据包。对于STEP-NC数控程序而言,首先是了解数控程序的组成部分和所描述的内容,所以数控系统必须首先对程序进行识别,然后对程序的信息进行提取。本研究针对STEP-NC程序的描述内容,通过程序读取模块,实现了对STEP-NC程序的读取,并通过程序信息提取模块对程序信息进行了提取,将STEP-NC中的实体映射为类对象进行处理,最后经过信息树等的模块,验证了程序读取和程序信息提取模块的正确性。本研究针对程序中所提取到的信息,特别是加工工艺参数信息进行了研究,建立了加工工艺参数的函数优化模型,并开发了相应的模块,通过与实际加工实例的比较,验证了该优化模型及模块的理论可行性。另外,本文针对典型的STEP-NC车削特征进行加工技术解析和加工工艺路径规划的研究。针对完整工件的加工,进行工步划分与调整的研究,并开发相应模块。本文还通过三维模型显示系统对工件模型及其路径规划进行构建和显示。最后通过STEP-NC标准中的一个典型的工件实例,对上述的理论研究和模块开发做了相应的验证。更多还原

【Abstract】 In the trend of the higher productivity, higher quality of the product and lower production cost, NC is commonly used in manufacturing as an advanced manufacturing Technology, and turning is one of the most important manufacturing methods, In the current, NC systems are controlled by the G code (ISO6983), massages are transferred only in one direction, from the PC to the control card, NC system control the CNC machine tools’movement only by G code programs, problems in processing can not be directly feedback to the design stage, so ISO6983 is difficult to support the advanced manufacturing methods and the intelligent CNC systems.In 1997, west industrialized countries, the EU and the United States for examples, proposed a new CNC interface standard called STEP-NC, in order to improve the data exchange ability in CAD/CAPP/CAM/CNC modules and overcome the shortcomings of ISO6983. STEP-NC is the expansion of the STEP standard to the NC field, the purpose is to build a information superhighway between the design and manufacturing process. ISO 14649-12, as the part 12 of the STEP-NC, describes the data model and technical for STEP-NC turning in details. With the integration and intelligence of manufacturing systems, STEP-NC turning technology will have a broad prospective development.This study is one part of the development of the intelligent STEP-NC turning, introduces the data model and information extraction methods briefly, focuses on the optimization of process parameters, studies the process planning and path planning, and carries out the data transformation between the PC and NC control card with study above, as a part of STEP-NC turning development work.For the STEP-NC program, the first is to learn the components and the content which the program describes, and the STEP-NC turning system identifies the program and extracts the information from it. According to the content of the STEP-NC program, this study realizes to read STEP-NC program through the read module and extract the information from the program through the information extraction module, then the entities in the STEP-NC program are mapped to classes and processed, this study proves the feasibility of the read module and information extraction module through information trees and other modules at last.In addition, this research studies the information extracted from the program, especially the processing parameters, establishes the optimization model and develops the corresponding module for the processing parameters. The optimization theory and the optimization module are feasibility through the comparing with the example instanced in the actual process. Besides this paper analyzes the Technology and studies the path planning for the typical characteristics of STEP-NC turning. Also, this research studies the division and adjustment, and develops the corresponding module for the whole workpiece. This paper displays the whole workpiece and the path planning through three-dimensional display module. Finally, this study proves the feasibility of the theory and the corresponding modules through an example instanced in the STEP-NC standard.更多还原