【作者】 周旺兵；

【导师】 徐步云； 梁宏宝；

【作者基本信息】 大庆石油学院 ， 机械设计及理论， 2003， 硕士

【摘要】 虚拟加工技术是指数控机床在虚拟环境中的映射，它集制造技术、机床数控理论、计算机辅助设计(CAD)、计算机辅助制造(CAM)和建模与仿真技术于一体。人能够凭直觉感知计算机产生的三维仿真模型的虚拟环境，虚拟加工过程能为产品设计可制造性的分析提供关键数据。在实际数控加工过程中，为了校验数控代码的正确性，需要进行反复试切直至确认数控代码能够完成预定的加工任务，同时数控加工参数也需要反复调试，这些操作不仅效率低下，占用了机器资源，而且有可能引起刀具碰撞或干涉等问题而造成经济损失。虚拟加工过程，能节省资源并避免风险。它的好处还体现在通过真实地模拟机床加工过程的行为来快速地对机床操作人员进行培训，也可帮助机床制造商向潜在的远程客户逼真演示其产品。该技术的采用可缩短产品的开发周期，降低生产成本，提高产品质量和生产效率。随着科学技术的进步，虚拟加工将在虚拟制造业中发挥其更大的作用。 本文从虚拟产品的可加工性角度出发，对虚拟加工环境的结构及其关键技术进行了研究，并开发了一个三维虚拟加工环境原型系统，其中的设备单元为一个虚拟铣削加工中心。系统在NC代码或刀位文件的驱动下运行，在加工过程中可连续不断地改变视角，以观察加工过程中加工中心的部件运动、零件和型腔的成型过程。该原型系统的仿真效果具有真实感强，实时性好的优点，可用于对设计的产品进行可加工性验证。 在国内虚拟机床技术研究的基础上，本文对数控加工过程的可视化进行了研究，包括虚拟加工环境的建造、刀具轨迹的优化模型及刀位计算、虚拟加工的NC代码翻译与实现，并着重于虚拟加工的NC代码翻译与实现的算法研究。总结出一套虚拟加工技术的实施方案。本系统以Windows98为开发平台，采用C++Builder软件及三维图形软件标准接口OpenGL为工具，初步设计了整个虚拟加工的过程。系统的结构包括： (1)虚拟加工环境：虚拟加工环境由机床、工件、刀具和夹具构成，采用OpenGL和CAD对机床、夹具、刀具和工件进行特征造型。 (2)虚拟加工过程：包括数控程序译码、三维动画仿真。数控加工过程仿真主要指几何仿真。几何仿真将刀具与零件视为刚体，不考虑切削参数、切削力及其它因素对切削加工的影响，只是对数控程序进行翻译，产生刀具位置数据，并以此数据驱动机床运动部件和刀架运动，刀具对工件进行虚拟切削等。更多还原

【Abstract】 The technology of virtual machining is the reflection of numerical controlling machine tool in the virtual environment, it make the manufacturing technology, the numerical controlling theory of machine tool, the Computer Aided Design (CAD), the Computer Aided Manufacture (CAM), the technology of modeling and simulation into a whole system. The people can feel the virtual environment of 3D simulative model produced by computer depending on instinct; the process of virtual manufacturing provides key data to analyze the producibility of product design. In the real process of numerical controlling machining, it is necessary to try cutting repeatedly until we can affirm that the numerical controlling code can accomplish scheduled machining task in order to verify the validity of the numerical controlling code. At the same time, numerical controlling machining parameter needs also to debug repeatedly, these operations not only have lower efficiency and occupy the machine resource, but also have the possibility to make the tool collision and interference and other problems. The process of virtual manufacturing can save the resources and avoid risk. The benefit of the process of virtual manufacturing also shows that it can train the operators of machine tool through simulating really the machine tool’s machining process, and help the machine tool’s manufacturer to demonstrate realistically their products to latent long-distance clients. The using of virtual manufacturing technology can shorten period of the product’s development, lower the production cost, advance product’s quality and producing efficiency. With the developing of the science and technology, virtual machining willbring into play great roles in the virtual manufacturing.The paper studies the configuration and key technology of the virtual machining environment from the point of view of virtual product’s machinability, and develops one archetypal system of three-dimensions virtual machining environment; the equipment unit among the system is a virtual milling-machining center. When the system is running driven by the NC code, it can change continuously the angle of view in the process of machining to observe the parts moving of the machining center and the molding procedure of the part and model-cavity. The effect of simulating of this archetypal system is excellence and better real time; the archetypal system can be used to verify the machinability to the designed virtual prototype of products.Basing on studying internal virtual machine tool technology, the author researches the visibility to the numerical controlling machining process, the algorithm research of setup of the virtual machine environment, optimization module of the trace of the tool and calculation of the tool position, the translation and achievement of NC-code. And focus on the algorithm research of the translation and achievement of NC-code, and has summed up a set of actualizing scheme of virtual machining technology. Taking Windows 98 as the development platform and using C++ software and 3D Graphical software standard interface OpenGL as tools. This system designs basically the whole virtual machining process. The modules of the system including:1. Virtual machining environment: virtual machining environment is made up of machine tool, workpiece, cutter and clamp, and uses OpenGL and CAD to carry through the feature modeling to machine tool, workpiece, cutter and clamp. II2. Virtual machining process: this module includes the NC program coding, the 3D animation simulation. The numerical controlling machining process simulation mainly is geometry simulation. The geometry simulation looks the cutter and parts as rigid body, not considers cutting parameter, cutting force and other factors’ influence to cutting machining, only translates numerical controlling program, gives birth to the cutting position’s data, and uses these data to drive machine tool’s moving parts, the tool cuts workpiece in virtual environment.更多还原