【正文】 aracteristics, etc. Once the virtual prototype is created, it can be used by the designers to evaluate the success or merit of the design configuration, and then modify it if desired. The product model represents the engineering intent behind a geometric design. The information contained in a product model includes physical attributes like geometry, material type and functional constrains. Generative technology There are three types of KBE tools that are currently being explored and developed. These include： 10 1. Diagnostic approach (expert system). 2. Creative approach (design advisor)/(design checking). 3. Generative approach (virtual prototype). The expert system was the first type of tool developed for use in the engineering tool is used for diagnostic purposes such as analyzing a malfunctioning automobile engine. The second type,design advisor,is the one to more current is used to follow the design process of a system, and advise the designer of constraint and rules violations based on rules contained with the design advisor. The designer then acts on this advice and makes appropriate changes. The third type involves developing a model of the system based on rules contained with the model. This model, a virtual prototype, then reacts to changes in attributes (either geometric or nongeometric), and regenerating a new instance of the prototype. This is the type of KBE that is used in the classes developed. KBE uses generative technology to capture generic product design information, including geometry and topology, product structure development and manufacturing processes as design rules. Generative modeling maps functional specifications to a detailed representation of the product. The advantage of a generative model is that as the product requirements change, the design representation is immediately updated directly affecting all outputs. Thus, KBE is a dynamic object model wherein the representation of the design is continually updated. KBE methodology facilities the capture of engineering and manufacturing knowledge into a generative model by rapidly generating new designs from functional specifications. In contrast to the conventional design tools, KBE offers true design automation vs. design assistance. KBE is a robust design technology for continuous redesign of a system during the design process. KBE product representation Current KBE software is based on an objectoriented nonprocedural design language such as LISP. As a result, the design information need not be ordered correctly within the model, as it will work out the order itself. Objectoriented programming works on the concept of objects that are used to represent the characteristics, both geometric and 11 nongeometric, of actual physical objects. Objects are not passive, but can react with other objects. An object can create and store information and act in response to external stimuli. An object can demand information from another object, or send information to another object. KBE enables true concurrent engineering by capturing the domain expertise of a range of contributors in an organization. This can include represent atives from design, engineering, tooling and other areas of manufacturing. KBE vendors have a wellestablished methodology for capturing and codifying this range of product information. Often, KBE developers will collaborate with methodology consultants to learn the `knowledge capture39。設(shè)計規(guī)則來定義和涉及雙方在知識經(jīng)濟(jì)模式的屬性。 ： 首次原 則為基礎(chǔ)的分析或數(shù)值模式的形式 。這些都是的類型，如果 (條件為真 )，然后 (行動推薦 )。 虛擬的影響，雖然沒有實際的事實 ： [1]基于計算機(jī)模型 原型 ： 原來的模式，或一個具體的例子類型。它可以存儲諸如幾何和材料規(guī)格，以及過程和性能信息產(chǎn)品信息。一個產(chǎn)品 (一個對象 )的幾何屬性中嵌入了 KBE 的模式。 GVP 公司的捕獲和自動化功能設(shè)計的規(guī)則和方法的理解在工程過程。智能 CAD 使用為元設(shè)計，這是 設(shè)計工具設(shè)計在一個產(chǎn)品模型的形式。所有這些集成