【機械類畢業(yè)論文中英文對照文獻翻譯】基于智能代理的分布式數(shù)字控制仿真系統(tǒng)
【機械類畢業(yè)論文中英文對照文獻翻譯】基于智能代理的分布式數(shù)字控制仿真系統(tǒng),機械類畢業(yè)論文中英文對照文獻翻譯,機械類,畢業(yè)論文,中英文,對照,對比,比照,文獻,翻譯,基于,智能,代理,分布式,數(shù)字控制,仿真,系統(tǒng)
南京理工大學(xué)泰州科技學(xué)院
畢業(yè)設(shè)計(論文)外文資料翻譯
系 部: 機械工程系
專 業(yè): 機械工程及自動化
姓 名: 徐長慶
學(xué) 號: 05010141
(用外文寫)
外文出處: Proceedings of the Fourth International Conference on Machine Learning and Cybernetics, Guangzhou, 18-21 August 2005
附 件: 1.外文資料翻譯譯文;2.外文原文。
指導(dǎo)教師評語:
簽名:
年 月 日
附件1:外文資料翻譯譯文
基于智能代理的分布式數(shù)字控制仿真系統(tǒng)
摘要 數(shù)控仿真是虛擬制造中的一個重要組成部分,可以測試,調(diào)試和優(yōu)化數(shù)控程序。然而,基于Web的分布式數(shù)控加工系統(tǒng)的發(fā)展正面臨支持實時網(wǎng)絡(luò)渲染和遠(yuǎn)程仿真切削過程智能控制的困難。首先,本文討論了多代理框架,以EAI為橋梁,采用虛擬現(xiàn)實建模語句來對刀具和工件建模,用Java控制銑削仿真過程。其次,對實現(xiàn)3關(guān)鍵因素的新的編程方法,即時間插值代理, NC代碼循環(huán)監(jiān)測代理,動態(tài)仿真清除代理,進行了詳細(xì)的描述。
關(guān)鍵詞 多代理系統(tǒng) 網(wǎng)絡(luò)制造 虛擬制造 分布式仿真
1 導(dǎo)言
虛擬制造系統(tǒng)(VM)是一個以計算機為基礎(chǔ)的綜合性模式,代表了物理和邏輯架構(gòu)行為的一個真正的制造系統(tǒng)。在將此應(yīng)用于生產(chǎn)線上之前進行估算和優(yōu)化設(shè)計,是VM的最主要的的目標(biāo)。虛擬數(shù)控加工是VM的一個重要的組成部分,它可以測試,調(diào)試和優(yōu)化數(shù)控程序。數(shù)控校驗一直是數(shù)控加工的一個主要的一部分。傳統(tǒng)的數(shù)控校驗方法是使用真正的廉價材料、真實的機床來進行驗證,顯然的缺點是花錢,花時間考慮和低效率。
網(wǎng)絡(luò)制造是一個最近幾年提出的新概念,它能夠集成了內(nèi)部和外部資源。網(wǎng)絡(luò)制造的核心是資源共享,這是一個好的辦法來降低企業(yè)集團的成本。智能仿真技術(shù)和網(wǎng)絡(luò)的迅猛發(fā)展使我們能夠建立一個基于網(wǎng)絡(luò)的虛擬數(shù)控加工系統(tǒng)。基于web的虛擬數(shù)控加工系統(tǒng)可以分布在網(wǎng)絡(luò)中,使很多用戶受益,而無需提高成本的數(shù)控驗證方法。但是,發(fā)展基于網(wǎng)絡(luò)的虛擬數(shù)控加工系統(tǒng)正面臨著2個困難。首先是應(yīng)支持網(wǎng)絡(luò)實時渲染和遠(yuǎn)程控制的智能框架。第二個是模擬切割過程,涉及工件動態(tài)建模。以銑削仿真作為個案研究,這項研究采用多代理技術(shù)實現(xiàn),通過借助虛擬現(xiàn)實建模語言( VRML的)和JAVE外部創(chuàng)作接口(EAI) 以克服上述困難。
2 用于遠(yuǎn)程仿真的智能代理框架
基于網(wǎng)絡(luò)的三維仿真的智能代理框架是由技術(shù)框架和文件框架所組成。
分布式數(shù)控銑床仿真過程采用基于WEB的3D圖形技術(shù)。目前典型的支持WEB的3D翻譯包只有Java 3D和VRML。3D API是一個作為接口復(fù)雜的三維圖像和聲音渲染系統(tǒng),它與Java是同一個層次的。Java 3D提供了高層次構(gòu)建創(chuàng)建和操縱三維幾何結(jié)構(gòu),并建立該幾何使用的結(jié)構(gòu)。至于細(xì)節(jié)渲染,則是自動處理,開發(fā)人員利用Java的線程,使用這個Java 3D可以有效地建立精確的虛擬網(wǎng)絡(luò)。雖然Java 3D是能自動優(yōu)化改進他們的渲染性能,但是,很難找到一個函數(shù),能夠動態(tài)對工件進行建模,要求該工件能夠進行實時修改?;镜腁PI動態(tài)模型的構(gòu)建應(yīng)該滿足復(fù)雜的數(shù)據(jù)結(jié)構(gòu)和不確定的數(shù)據(jù)量。
和Java 3D相比 ,VRML虛擬現(xiàn)實操作語言,能夠通過互聯(lián)網(wǎng)和超文本鏈接與萬維網(wǎng)來創(chuàng)建網(wǎng)絡(luò)虛擬世界,是一個更好的辦法來創(chuàng)建工件模型以支持遠(yuǎn)程3D仿真?;雍途W(wǎng)絡(luò)交互可以使用VRML定義,而不必依賴于頭盔式設(shè)備(HMD)。它的開發(fā)VRML的設(shè)計者的意圖在于使VRML成為交互仿真的萬維網(wǎng)的標(biāo)準(zhǔn)語言。易于使用是VRML的優(yōu)點。 VRML用與用來建立標(biāo)準(zhǔn)的網(wǎng)頁的HTML一樣的方式來建立三維世界萬維網(wǎng)。對于工件建模,關(guān)鍵的優(yōu)勢在于它包含了一些不同的動力學(xué)形狀節(jié)點,來描述一個物體如何呈現(xiàn),這些將在后面給予描述。上述2個優(yōu)點決定采取VRML來作為遠(yuǎn)程三維工件建模的工具。
VRML的一個主要的缺點是,如果只用VRML來建造虛擬場景,它的互動能力較弱。只有導(dǎo)航,移動物體和變化的觀點是一致的。動態(tài)控制VRML的剖面模型來實現(xiàn)智能仿真很難。EAI是解決困難的一個很好的方法。EAI可以讓您控制VRML的瀏覽器窗口的內(nèi)容,該窗口嵌入到一個與Java applet同一頁的網(wǎng)頁。為此,它使用一個瀏覽器插件接口,該接口允許嵌入到網(wǎng)頁的對象可以互相溝通。因此,建立了一個技術(shù)框架,該架構(gòu)由是又基于VRML的刀具和工件模型,基于JAVA的智能銑削過車仿真過程控制和以EAI作為代理的生成者組成。其智能代理框架圖如圖1所示
圖1 智能代理框架
目前有一些瀏覽器支持EAI ,如Netscape Communicator的4.04用于Macintosh , Netscape Communicator的4.04為Win32的,還有Netscape Navigator 3.01S適用于IRIX 。有些插件可以用來運行VRML,如用于Macintosh的Cosmo Player 2.1或更高版本。這項研究采用Netscape Communicator的4.04 和 Cosmo Software的Cosmo Player2.1來運行系統(tǒng)。這些文件的框架都如圖1 所示。 VRML文件所包含的sta_model.wrl用來建立靜態(tài)的模型,如刀具模型。dyn_model.wrl用來建立動態(tài)模型,如工件的模型。用戶通過EAI和導(dǎo)航器和cosmo player的applet來訪問和操縱虛擬場景。 VirtualNC.html是虛擬場景和用戶之間的接口。
3 切削仿真的智能代理
為了使數(shù)控銑床系統(tǒng)的運行就像是機床工具本身那樣,顯示出機械運動和材料去除是至關(guān)重要的。目前,許多三維建模包是可以達到的,如OpenGL以及的Direct3D軟件包 。然而,當(dāng)使用當(dāng)前的三維造型包創(chuàng)建的模型沉浸在一個虛擬的環(huán)境,其輪廓函數(shù)就無法實時修改。這項研究采用了VRML中附有金屬光效果的ElevationGrid節(jié)點,以實施動態(tài)工件大小的變換。
xDimension , zDimension ,和高度領(lǐng)域是處理支持節(jié)點的VRML ElevationGrid關(guān)鍵領(lǐng)域的動態(tài)模型。該xDimension和zDimension領(lǐng)域表明,一些網(wǎng)格高度陣列在X和Z方向上的原理。重復(fù)檢查是執(zhí)行實時工件材料去除過程的根本原則。當(dāng)發(fā)現(xiàn)輸入NC代碼重疊,建立于dyn_model.wrl中動態(tài)模型垂直高度上的頂點,以及建立在sta_model.wrl中模型的刀具圓圈內(nèi)點,將設(shè)置與刀具相同的高度。實現(xiàn)銑削仿真包含三個主要代理模塊代理,舉例如下:
(1)時間插補代理
DEF TS_XZ TimeSensor{ cycleInterval 32 loop FALSE }
ROUTE CLOCK.cycleTime TO SCRIPT.cycleTime
ROUTE Trsf_Y.translation_changed TO SCRIPT.Ytranslation
ROUTE Trsf_XZ.translation_changedTO SCRIPT.XZtranslation
ROUTE SCRIPT.height TO EGRID.set_height
(2) NC代碼循環(huán)監(jiān)測代理
public void ValueChanged extends Applet implements ActionListener, EventOutObserver { TheTextField.setText(String.valueOf(TheScrollbar.getValue()));
Output.append("Set Scale Value:" + " x=" + ScaleValue[0] + " y=" + ScaleValue[1]+ " z=" + ScaleValue[2] + "\n");
Output.append("Set Trans Value:" + " x=" + XZTransValue[0] + " y=" + YTransValue[1]+ " z=" + XZTransValue[2] + "\n");
set_XZtranslation.setValue(XZTransValue);
set_Ytranslation.setValue(YTransValue);
GcodeInput=new TextArea(init_input, val);
add(GcodeInput); }
(3)動態(tài)仿真清除代理
set_height_changing( )
{if( (((var_float+XZPosition[0])-(x*Long))*(( var_float+XZPosition[1])-(x*Long))+((var_float+XZPosition[1])-(z*z_Long))*((var_float+XZPosition[1])-(z*Long)))<=(R*R_cut) )
height.setValue( heightFields ); }
4 結(jié)論
一種結(jié)合了最新圖像技術(shù)、智能代理技術(shù)、網(wǎng)絡(luò)技術(shù)的分布式智能銑削系統(tǒng)已被成功開發(fā)。該系統(tǒng)可以使用戶去看、去操作,并且能夠在網(wǎng)絡(luò)上共享一個虛擬數(shù)據(jù)銑削機床。這個系統(tǒng)檢測所有數(shù)控程序的錯誤,可以立即在線糾正。由于這一系統(tǒng)在標(biāo)準(zhǔn)的Windows平臺上運行,對用戶沒有外部的附加要求,因此它很容易使用。
致謝
本文是湖北省青年精英自然科學(xué)基金組織( No.2005ABB023 )所提供 ,武漢市曙光計劃( No.20055003059 )
附件2:外文原文(復(fù)印件)
Proceedings of the Fourth International Conference on Machine Learning and Cybernetics, Guangzhou, 18-21 August 2005
INTELLIGENT AGENT-ENABLED DISTRIBUTED NUMERICAL CONTROL SIMULATION SYSTEM
YA-BO LUO, DING-FANG CHEN
School of Mechanical and Electrical Engineering,
Wuhan University of Technology, Wuhan 430070, China
E-MAIL: luoyabo1973@sohu.com, dfchen@public.wh.hb.cn
Abstract:
NC simulation is an important component of virtual manufacturing, which enables testing, debugging and optimizing of NC programs in advance. However, development of web-based distributed NC machining system is facing difficulties of intelligent control supporting real-time rendering over web and the remote simulation of cutting process. First, this paper addresses the multi-agents framework, which employs VRML to model the models of cutter and workpiece, and Java to control the process of milling simulation, taking the EAI as the bridge. Second, the novel programming methodologies for the realization of 3 key majority agents, namely, time the interpolation agent, NC codes flow listener agent, and the dynamical removal simulation agent, are detailed represented.
Keywords:
Multi-agents system; net manufacturing; virtual manufacturing; distributed simulation
1. Introduction
A virtual manufacturing (VM) system is an integrated computer-based model that represents the physical and logical schema and the behavior of a real manufacturing system [1]. Pre-estimating and optimizing the design before it is putted on the product line is the main objective of VM. Virtual NC machining is an important component of VM, which enable testing, debugging and optimizing of NC programs. NC verification has always been the majority part of NC machining [2]. Traditional method for NC verification is to test the programming using real machine tools with cheap material, obviously which disadvantage is expensive, time taking and low efficient.
Net manufacturing is a fresh concept proposed in recently years, which integrates the internal and external resources of enterprises group. The core of net manufacturing is resource sharing, which is a good approach to lower the cost of enterprises group.
The rapid development of intelligent simulation and net technologies makes it possible to develop a web-based virtual NC machining system. A web-based virtual NC machining system can be distributed on web to benefit many users without having to improve the cost of NC verification. However, development of web-based virtual NC machining system is facing 2 difficulties [3]. The first is the intelligent framework, which should support real-time rendering and remote control over web. The second is the simulation of cutting process involving the workpiece dynamical modeling. Taking milling simulation as case study, this research employs multi-agents technology realized through virtual reality modeling language (VRML) and Jave external authoring interface (EAI) to overcome the above difficulties.
2. Intelligent agents framework for remote simulation
The intelligent framework for 3D simulation over web comprises of technologies framework and files framework.
The distributed NC milling simulation deals with 3D graphic technology over web. Currently the typical 3D rendering packages on web are Java 3D and VRML. The Java 3D API is a hierarchy of Java classes that serve as the interface to a sophisticated three-dimensional graphics and sound rendering system. Java 3D provides high-level constructs to create and manipulate 3D geometry, and to build the structures used to render that geometry [4]. As the details of rendering are handled automatically, developers can efficiently create precise virtual universes on web using this Java 3D package taking advantage of Java threads. Though the Java 3D is capable of automatically optimizing for improved rendering performance, however, it is difficult to find a function to dynamically model the work-piece, which should have capability to be modified in real time. A dynamic model constructed by the elementary API should meet complex data structure and uncertain data amount.
Compared to the Java 3D, VRML, which allows to create virtual worlds networked via the Internet and hyperlinked with the World Wide Web, is a better approach to create work-piece model supporting remote 3Dsimulation. Interaction and internetworking can be specified using VRML without being dependent on special gear like head-mounted devices (HMD). It is the intention of its designers to develop VRML as the standard language for interactive simulation within the World Wide Web. Ease to use is an advantage of VRML. VRML is used in the same way to build 3-D worlds on the World Wide Web as HTML is used to build standard Web pages. For work-piece modeling, the crucial advantage is it contains some various dynamical shape nodes comprising of fields to describe how an object is rendered, which will be represented late. The above 2 advantages decide on that it is advisable to take the VRML as the tool for remote 3D work-piece modeling.
A main disadvantage of VRML is that a virtual scene constructed with only VRML has poor interaction capability. Only navigation, moving object and viewpoint changing are agreed. Dynamic controlling the profiles of VRML models to realize intelligent simulation is difficult. The EAI is a good solution to the difficulty. EAI allows you to control the contents of a VRML browser window embedded in a web page from a Java applet on the same page. It does this with a browser plug-in interface that allows embedded objects on web page to communicate with each other. Consequently, the technologies framework is built by employing VRML to model the models of cutter and work-piece, and Java to control the process of intelligent milling simulation, taking the EAI as the agent maker.
Current there are some browser agree EAI, such as the Netscape Communicator 4.04 for Macintosh, Netscape Communicator 4.04 for Win32, and the Netscape Navigator 3.01S for IRIX. Some plug-ins can be employed to run VRML files, such as Cosmo Player 2.1 or later for Macintosh. This research employs Netscape Communicator 4.04 + Cosmo Software Cosmo Player 2.1 to run the system. The files framework is showed as in Figure 1. VRML files comprise of sta_model.wrl used to build static models such as the cutter model and dyn_model.wrl used to build dynamic models such as the workpiece model. Users visit and manipulate the virtual scene by EAI and applet through the navigator and cosmo player. VirtualNC.html is the interface between virtual scene and users.
3. Intelligent agents for cutting simulation
To make a NC milling system to run as if they were on the machine tool itself, showing machine motion and material removal is crucial. Currently, many 3D modeling packages are available such as the OpenGL, and the Direct3D soft packages. However, when a model constructed with a current 3D modeling package is immersed in a virtual environment, its profile function cannot be modified in real time. This research employs the VRML ElevationGrid node attached with the metal light effect to implement a dynamical work-piece with variable sizes.
The xDimension, zDimension, and the height fields address the key fields of VRML ElevationGrid node in favor of dynamical modeling. The xDimension and zDimension fields indicate the number of elements of the grid height array in the X and Z directions. Overlap checks is fundamental for implementing the real-time workpiece material removal process. When an overlap is detected along with the inputted NC codes, the heights of these vertices of dynamical model, which is built in the dyn_model.wrl, inside the circle of the cutter, which is modeled in the sta_model.wrl, will be set equal to the height of the cutter. The realization of milling simulation contains 3 key majority agents modules demonstrated as followings.
(1) Time interpolation agent
DEF TS_XZ TimeSensor{ cycleInterval 32 loop FALSE }
ROUTE CLOCK.cycleTime TO SCRIPT.cycleTime
ROUTE Trsf_Y.translation_changed TO SCRIPT.Ytranslation
ROUTE Trsf_XZ.translation_changedTO SCRIPT.XZtranslation
ROUTE SCRIPT.height TO EGRID.set_height
(2) NC codes flow listener agent
public void ValueChanged extends Applet implements ActionListener, EventOutObserver {
TheTextField.setText(String.valueOf(TheScrollbar.getValue()));
Output.append("Set Scale Value:" + " x=" + ScaleValue[0] + " y=" + ScaleValue[1]+ " z=" + ScaleValue[2] + "\n");
Output.append("Set Trans Value:" + " x=" + XZTransValue[0] + " y=" + YTransValue[1]+ " z=" + XZTransValue[2] + "\n");
set_XZtranslation.setValue(XZTransValue);
set_Ytranslation.setValue(YTransValue);
GcodeInput=new TextArea(init_input, val);
add(GcodeInput); }
(3) Dynamical removal simulation agent
set_height_changing(){ if( (((var_float+XZPosition[0])-(x*Long))*(( var_float+XZPosition[1])-(x*Long))+((var_float+XZPosition[1])-(z*z_Long))*(( var_float+XZPosition[1])-(z*Long)))<=(R*R_cut) ) height.setValue( heightFields ); }
4. conclusions
A distributed intelligent milling system has been developed by the above key technologies combining the latest graphics, net with intelligent agent technologies. It enables users to see, manipulate, and share a virtual NC milling machine on Internet. This system detects all NC program errors, which can be immediately corrected online. Since this system runs on standard Windows platforms, and no exterior attachment is required to users, thus it is ease to use.
Acknowledgements
This paper is supported by the Hubei province Natural Science Fund for young elitist (No.2005ABB023), Wuhan city dawn plan (No.20055003059).
References
[1] K. L. Lee, and S. D. Noh, “Virtual manufacturing system-a test bed of engineering activities”, Annuals of the CIRP, Vol 46, No.1, pp.347-350, 2002.
[2] H. Narita, K. Shirase, H. Wakamatsu, A. Tsumaya and E. Arai, “Real-time cutting simulation system of a milling operation for autonomous and intelligent machine tools”, International Journal of Production Research, Vol 40, No.15, pp.3791-3806, 2002.
[3] Y. B. Luo, S. K. Ong, D. F. Chen, A. Y. C. Nee, “An Internet-enabled image- and model-based virtual machining system”, International Journal of Production Research, Vol 40, No.10, pp.2269-2289, 2002.
[4] L. H. Wang, R. Sams, M. Verner and F. F. Xi, “Integrating Java 3D model and sensor data for remote monitoring and control”, Robotics & Computer-Integrated Manufacting, Vol 19, No.1/2, pp.13-20, 2002.
收藏