中英文翻译--虚拟制造技术{修}

Virtual Manufacturing

What is Virtual Manufacturring

Virtual manufacturing(VM) is an integrated, synthetic manufacturing environment exercised to enhance all leveles of decision and control in a manufaceturing enterprise. VM can be described as a simulated model of the actual manufacturing setup which may or may not exist. It holds all the information relating to the process , the process control and management and product specific data. It is also possible to have part of the manufacturing plant be real and the other part virtual . Virtual manufacturing is the use of computer models and simulations of manufacturing process to aid in design and production of manufactured products.

Lawrence Associate[1996], have identified three different types of Virtual Manufacturing paradigms that use Virtual Reality technology to provide the integrated environment.

(1)Design-centered VM: provides designers with the tools to design products that meet design criteria such as design for X

(2)Production-centered VM: provides the means develop and analyse alternative production the process plans;

(3)Control-centered VM: allows the evaluation of product design, production plans, and control strategy and a means to iteratively to improve all of them through the simulation of the control process.

What is the Significance of VM

VM aims at providing an integrated environment for a number of isolated manufacturing technologies such as Computer Aided Design , Computer Aided Manufacturing, and Computer Aided Process Planning, thus allowing multiple users to concurrently carry out all or some of these functions without the need for being physically close to each other. For example, a process planning engineer and a manufacturing engineer can evaluate and provide feedback to a product designer, who may be physically located in another state or country, at the same time as the design is being conceived.

Another important contribution of VM is Virtual Engerprise(VE). Lin et al[1995] defined a Virtual E nterprise as “rapidly configur ed multi-disciplinary network of small, process specific firms configured to meet a window of opportunity to design and produce a specific product.” Using this techonology, a group of people , or corporations can pool their expertise and resources and capitalize a market opportunity, by sharing informatiion in a VM environment. The principal advantage of this technology is its ability to provide a multi-media envirnoment , enhancing communication at all levels in a product’s life cycle.

Application of VM

Application of VM encompass the entire life cycle of a product. Reported developments include a virtual space decision support system by Imamura and Nomural[1994] at the Matsushita company in Japan. This system applied towards the marketing and sales of kitchen furniture, allows customers to experience a kitchen environment and evaluate alternatives and select the best combination according to

preferences. Their preferences are stored as drawings and subsequently transferred to the company’s production facilities.

Owen[1994] presented the work impleme nted at John Deere Company’s production facility, that used Virtual Manufacturing for the installation of an arc welding production system. The project involved using a Virtual 3-D environment for design, evaluation, and testing of the robotic production system. Part of the work was carried out at John Deere facility’s while part of it was done by Genesis System and Technomatrix Technologies. The VM approach helped shorten the design-to-manufacturing cycle-time.

DuPont[1994] presented an overview of Virtual Reality applications, and reported about Virtual prototyping being carried out at the Coventty School of Art and Design. These virtual prototypes are constructed in a computer at the beginning of the design process and allow the designer to perform tests on the virtual prototype such as a car beforehand, by walking around or through the design, examine its performance on a virtual road , sit in the driver’s seat , and check view lines, etc. Also reported were VM applications such as the virtual concurrent design and assembly of a landing gear, and simulation of side-impact collision to test vehicle safety.

Kim et al.[1994] also reported VR applications including the use of VM by designers at Boeing Aircraft Company for the ergonomic evaluation of their airplane designs for operation as well as maintenance. Another study used a VM environment to train robots. An operator’s movements were recognized, interpreted and stored in the form of robotic movement command. Shenai described the Virtual Wafer Fabrication(VWF) infratructure which provided an framework for the optimization of the key process and design variables in the development of application specific semi-conductor devices. Other application areas discussed in Larijani[1994] include machine-vision applications for diagnosis, fault detection , inspection and preventive maintenance, safety and maintenance training, ergonomic analysis. For example , new cab or shovel configurations for each Caterpillar moving equipment are tested by real drivers for possible imbalances while handling virtual bulldozers and turcks.

虚拟制造技术

什么是虚拟制造技术

虚拟制造是人们使用的一种高度集成化的、虚拟的生产环境，其目的是为了增强制造业的各种决策和控制力。在现实生活中，人们把虚拟制造技术描述成一个可存在或可不存在的实际生产机构的仿真模型。该模型包含了所有与生产过程、生产过程控制管理和产品详细数据有关的信息；同时它也可能包含部分实际上存在或不存在的有关生产企业的信息。虚拟制造技术通过使用计算机模型来模拟生产过程，以达到产品设计与之招商有所帮助的目的。

1996年Lawrence Associate吧虚拟制造技术（该技术利用虚拟现实技术来提供集成环境的）分成3种不同的模式。

(1)以设计为中心的虚拟制造。该技术的特点是向设计者提供适当的工具来设计不同的产品。

(2)以生产为中心的虚拟制造。该技术的特点是向生产决策者提供一定的方法来分析、研究待选择的生产加工计划。

(3)以控制为中心的虚拟制造。该技术的特点是允许生产设计管理人员对产品设计、生产计划和控制决策进行评估，同时也允许生产设计管理人员采用对控制过程进行摸你的方法对产品设计、生产计划和控制觉车进行不断的改进。

虚拟制造技术的意义

虚拟制造技术的目的是向许多独立的制造技术提供一个集成化环境。这些技术包括计算机辅助设计、制造和过程规划。在这个虚拟制造的成环境中，有多种应用目的的用户无需将上述各技术紧密结合，就可完成部分甚至所有的任务。例如，一个生产过程的计划工程师和一个制造工程师能够对生产过程进行评估，并且可以将评估的结果反馈给住在异地的产品设计工程师，由他对产品进行改进设计。

虚拟制造技术的另外一个重要贡献是虚拟企业。1995年Lin et al.把虚拟企业定义成快速构造的小型专业公司的多学科联合。构造该企业的目的是完成某种专门产品的设计和生产。通过分享虚拟制造环境中的信息资源，许多人和公司借助该技术科共享它们之间的相关技术、资源和有利的市场机会。因此，虚拟制造技术的主要优点是能够向用户提供一个拥有多种媒体的虚拟环境，加强了产品循环周期各个层次的信息交流。

虚拟制造技术的应用

在实际应用过程中，虚拟制造技术往往贯穿产品的整个生命周期，比如，1994年日本Matsushita公司的Imamura和Nomura的一项研究成果中包括了一个可视化的空间决策系统。该系统主要应用于厨具销售领域。它首先允许顾客去感受某种厨房环境，然后由顾客对这些厨具进行比较，最后根据他们自己的喜好选择出最好的组合。当然，这些顾客的喜好会被记录起来，然后反馈给公司的生产机构。

Owen在1994年向公众介绍了John Deere公司生产部门所完成的一项研究成果，该成果利用虚拟制造技术实现了某种生产系统的安装过程。该项成果包括运用虚拟三维技术来设计、评估和测试机器人生产系统。在这项成果的研制过程中，有一些工作由John Deere公司完成的，而另外一些工作由Genesis系统和Technomatrix技术公司完成.此项虚拟制造技术的运用对于缩短该产品的设计-生产周期起了一定的作用。

1994年DuPont对虚拟现实技术的应用做了总的介绍，同时他对英国的

Coventry艺术与设计学院完成的虚拟样机进行了报道。这些虚拟样机刚开始是在计算机中构造完成的，这使得设计者可以在计算机上预先对它们（例如汽车）进行一些方面的测试。通过在计算机上运行这些虚拟样机，设计者可以对汽车在虚拟道路上的行驶性能、驾驶员坐在驾驶室的舒适程度及其开车时的视野状况等方面做一定的测试和检查。另外，虚拟制造技术还可应用在虚拟并行设计，飞机起落架的虚拟装配合和检测汽车碰撞性能的仿真等方面。

Kim et al.在1994年也报道了一些虚拟现实技术运用的实例，其中包括波音飞机公司的设计师们利用虚拟制造技术对所设计的飞机在操作和维护方面所做的一些有关飞机对环境影响方面的评估。另一个有关虚拟现实技术的运用实例是利用虚拟制造技术的环境训练机器人，即以机器人运动指令的形式对操作者的行为进行识别、解释并最终储存起来。Shennai描述了虚拟制造技术在胶片结构制作方面的应用（该技术被称为虚拟胶片构造技术）。该技术为特殊半导体在研制过程中的主要工艺和设计变量的优化提供了一定的方法。1994年Larijani还介绍了其他有关虚拟制造技术应用方面的实例，主要包括虚拟可视化技术在机器的故障诊断、故障检测、检查预防性维护、安全和维护培训及环境分析设计方面的应用。比如，Caterpillar公司的每一辆汽车和推土机均由实际驾驶人员通过在计算机上操作虚拟推土机和汽车，来检测它们在实际运行过程中可能出现的不平衡的问题。

出处：赵运才﹒机电工程专业英语﹒北京大学出版社﹒2006