【作者】 徐绍华；

【导师】 田新诚；

【作者基本信息】 山东大学 ， 系统工程， 2008， 硕士

【摘要】 焊接在国民经济发展和国防建设中具有非常重要的地位和作用。焊接已经渗透到制造业的各个领域,广泛应用于锅炉、压力容器、核电设施、石油管道、化工冶金、航空航天、建筑、医疗器械、精密仪器和电子等行业中。现在中国已经成为世界主要的焊接大国,但是我国焊接设备制造业起步较晚,焊接设备的自动化程度低,跟英、美、德、法、意和日本等世界工业发达国家之间的差距较大。空间相贯曲线是一种常见的复杂曲线,这类曲线的自动焊接是人们研究的热点和难点。在空间相贯曲线的自动焊接数控技术方面,大多靠引进美、德、奥地利等国的焊接数控设备,我国还没有掌握其关键技术,因此发展具有中国自主知识产权的空间相贯曲线数控自动焊接关键技术与产品是当前的迫切任务。焊缝曲线的准确描述是自动焊接的第一步,对保证焊接精度起着的非常关键的作用。本文在分析了空间解析几何学求焊缝曲线方法的局限性后,提出了采用B样条曲线算法拟合焊缝曲线,得到的是空间相贯线焊缝的参数表达式。采用MATLAB分析了B样条曲线拟合方法的精度。插补算法是数控系统的核心技术之一,高速、高精度的插补算法一直是学者们追求的目标。插补算法的特性直接影响到数控系统的控制精度、速度及加工能力等。本文对焊缝曲线的插补方法进行了研究,在分析了现有插补算法的基础上提出了一种通用的B样条曲线插补算法。本文提出的B样条曲线插补算法可以应用于直角坐标系和非直角坐标系下的运动控制,是一种快速、高精度的插补算法。并且应用MATLAB对本文的焊缝插补算法进行了验证。本文在最后设计了自动焊接控制系统,包括硬件系统设计和软件系统设计两个部分。硬件系统以IPC作为平台,设计的硬件系统体系结构具有开放式、模块化和嵌入式的特点。在软件部分充分考虑算法的复杂度,采用简便快速的算法以提高算法速度,降低内存需求,设计了高效、高质量的VC程序。VC程序采用了分模块的设计思路,对于不同的功能分别设计相应的模块。更多还原

【Abstract】 Welding plays a prime important role in many industries, including military industry. Now China’s welding industry has become the top one in the world, but it is still at a low automation level because of its late startup. There is still a large gap in the automated welding equipments between China and the main developed countries, such as Britain, the United States, Germany, France, Italy and Japan.The welding of Spatial Intersected Curves (SIC) is a common task in many industries. The automated welding of SIC has been drawing great attention from universities and research institutes because of its great importance in industries. The welding of SIC exists in many industries, such as car manufacturing, shipbuilding, oil transportation pressure vessels and water supply, etc. China has imported many automated equipments from USA, Germany, Austria for SIC welding, but we hasn’t mastered the core technology for automated SIC welding. There is the urgent need to research the key technology and to develop automated SIC welding equipment with our own independent intellectual property.The accurate description for welding seam is the fist step in automated welding, and it has an important effect on welding precision. This thesis first analyzes the limitation of the way of welding seam description through space geometric analysis, and then proposes a new method - welding seam fitting by B-spline curve algorithm, with which the mathematical parameterized expression of the seam will be acquired. Also the thesis analyzes the accuracy of the B-spline algorithm fitting method by MATLAB.The interpolation algorithm is the core technology of Numerical Control (NC) system, and high-speed and high-precision are always the targets for interpolation algorithm research. The thesis researches the B-spline interpolation algorithm for automated welding of SIC. Based on the analysis of traditional algorithms, a universal interpolation algorithm with high speed and high precision is proposed, which can be used for the motion control both in Cartesian coordinates and non-Cartesian coordinates systems. The B-spline interpolation algorithm for SIC welding is proved in the thesis with MATLAB.The automated welding control system is introduced in the thesis, including the hardware design and software programming. The hardware system adopts the Industrial Personal Computer (IPC) as the control platform, and the system structure has the opening, modular and embeddable characteristics. To improve the program execution efficiency and decrease the memory requirement, the complexity of the algorithms is fully considered to attain algorithm’s high-speed and high-efficiency. The program is written modularly with Visual C++.更多还原