3592 尾架體加工工藝及關鍵工序工裝設計
3592 尾架體加工工藝及關鍵工序工裝設計,尾架體,加工,工藝,關鍵,癥結,樞紐,工序,工裝,設計
機床生產(chǎn)率計算卡圖號 毛坯種類 鑄件名稱 尾架體 毛坯重量被加工零件材料 HT200 硬度 175~255HBS工序名稱 鉆 Φ14 孔 工序號 工時/min序號 工步名稱 工作行程/mm 切速/(m/min) 進給量/(mm/r) 進給量/(mm/min) 工進時間輔助時間1 安裝工件 0.72 工件定位、夾緊 0.053 鉆頭快進 200 5000 0.034 鉆頭工進 38 78 0.11 6.6 1.595 死擋鐵停留 0.016 鉆頭快退 238 5000 0.0367 工件松開 0.058 卸下工件 0.7累計 0.159 1.576單件總工時 1.612機床生產(chǎn)率 37.22(件/h)理論生產(chǎn)率 25.64(件/h)備注1.一次安裝加工一個工件2.本機床裝卸工件時間取 1.4min負荷率 68.89%南京理工大學泰州科技學院畢業(yè)設計(論文)前期工作材料學 生 姓 名 : 張春雨 學 號: 05010106系 部 : 機械工程系專 業(yè) : 機械工程及自動化設計 (論 文 )題 目 : 尾架體加工工藝及關鍵工序工裝設計指 導 教 師 : 王栓虎 副教授材 料 目 錄序號 名 稱 數(shù)量 備 注1 畢業(yè)設計(論文)選題、審題表 12 畢業(yè)設計(論文)任務書 13 畢業(yè)設計(論文)開題報告〔含文獻綜述〕 14 畢業(yè)設計(論文)外文資料翻譯〔含原文〕 15 畢業(yè)設計(論文)中期檢查表 12009 年 5 月 南京理工大學泰州科技學院畢業(yè)設計(論文)任務書系 部 : 機械工程系專 業(yè) : 機械工程及自動化學 生 姓 名: 張春雨學 號:05010106設 計 (論 文 )題 目 : 尾架體加工工藝及關鍵工序工裝設計起 迄 日 期 : 2008 年 3月 09 日 ~ 6 月 14 日設計 (論文 )地點 : 南京理工大學泰州科技學院指 導 教 師 : 王栓虎專 業(yè) 負 責 人 : 龔光容發(fā)任務書日期: 2009 年 2 月 26 日任務書填寫要求1.畢業(yè)設計(論文)任務書由指導教師根據(jù)各課題的具體情況填寫,經(jīng)學生所在專業(yè)的負責人審查、系部領導簽字后生效。此任務書應在第七學期結束前填好并發(fā)給學生;2.任務書內容必須用黑墨水筆工整書寫或按教務處統(tǒng)一設計的電子文檔標準格式(可從教務處網(wǎng)頁上下載)打印,不得隨便涂改或潦草書寫,禁止打印在其它紙上后剪貼;3.任務書內填寫的內容,必須和學生畢業(yè)設計(論文)完成的情況相一致,若有變更,應當經(jīng)過所在專業(yè)及系部主管領導審批后方可重新填寫;4.任務書內有關“系部” 、 “專業(yè)”等名稱的填寫,應寫中文全稱,不能寫數(shù)字代碼。學生的“學號”要寫全號;5.任務書內“主要參考文獻”的填寫,應按照國標 GB 7714—2005《文后參考文獻著錄規(guī)則》的要求書寫,不能有隨意性;6.有關年月日等日期的填寫,應當按照國標 GB/T 7408—2005《數(shù)據(jù)元和交換格式、信息交換、日期和時間表示法》規(guī)定的要求,一律用阿拉伯數(shù)字書寫。如“2008 年 3 月 15 日”或“2008-03-15”。畢 業(yè) 設 計(論 文)任 務 書1.本畢業(yè)設計(論文)課題應達到的目的:尾架體是某企業(yè)產(chǎn)品中的關鍵零件之一,生產(chǎn)量比較大。為了保證產(chǎn)品質量,提高加工效率,需要對其加工工藝進行優(yōu)化設計,并在關鍵工序使用組合機床或專用機床進行加工。本課題即以此為背景,要求學生根據(jù)企業(yè)生產(chǎn)需要和尾架體零件的加工要求,首先完成零件的加工工藝規(guī)程設計,在此基礎之上,選擇其關鍵工序之一進行專用夾具及加工用組合機床設計,并完成必要的設計計算。通過這樣一個典型環(huán)節(jié)綜合訓練,達到綜合訓練學生運用所學知識,解決工程實際問題的能力。2.本畢業(yè)設計(論文)課題任務的內容和要求(包括原始數(shù)據(jù)、技術要求、工作要求等):本課題要求學生在對尾架體的加工要求、零件的結構工藝性進行認真分析的基礎上,首先對零件的加工工藝規(guī)程做出優(yōu)化設計,并對其關鍵工序之一進行專用夾具及加工用組合機床設計。具體任務及要求如下:(1)調查研究、查閱及翻譯文獻資料,撰寫開題報告;(2)尾架體加工要求、零件的結構工藝性分析;(3)尾架體加工工藝規(guī)程設計;(4)尾架體關鍵工序的專用夾具設計;(5)尾架體關鍵工序的組合機床設計;(6)必要的設計計算與分析;(7)文檔整理、撰寫畢業(yè)設計說明書及使用說明書。設計技術要求包括:(1)生產(chǎn)綱領 50000 件/年(2)夾具采用液壓驅動(3)組合機床采用液壓滑臺(4)每次加工一個零件畢 業(yè) 設 計(論 文)任 務 書3.對本畢業(yè)設計(論文)課題成果的要求〔包括畢業(yè)設計論文、圖表、實物樣品等〕:(1)開題報告、文獻綜述、資料翻譯;(2)尾架體加工工藝過程綜合卡及各工序工序卡;(3)尾架體零件圖及夾具裝配圖;(4)組合機床設計資料(三圖一卡) ;(5)畢業(yè)設計說明書。 4.主要參考文獻:[1] 裘愉弢主編. 組合機床[M]. 第 1 版.北京:機械工業(yè)出版社,1995.[2] 金振華主編.組合機床及其調整與使用[M]. 第 1 版.北京:機械工業(yè)出版社,1990.[3] 沈延山.生產(chǎn)實習與組合機床設計[D].第 1 版.大連:大連理工大學出版社,1989.[4] 上海市大專院校機械制造工藝學協(xié)作組編著.機械制造工藝學[M] (修訂版).福建科學技術出版社,1996.[5] 王華坤,范元勛編.機械設計基礎[M].北京:兵器工業(yè)出版社,2000.[6] 馮辛安等編.機械制造裝備設計[M]. 北京:機械工業(yè)出版社,1998.[7] 陳日曜主編.金屬切削原理[M]. 第 2 版.北京:機械工業(yè)出版社,1992.[8] 方子良等編.機械制造技術基礎[M].上海:上海交通大學出版社,2004.[9] 劉秋生,李忠文主編.液壓傳動與控制[M].北京:宇航出版社,1994.[10] 陳于萍,周兆元等.互換性與測量技術基礎[M]. 第 2 版.北京:機械工業(yè)出版社,2005.[11] 東北重型機械學院等合編.機床夾具設計手冊[M].上海:上??茖W技術出版社,1979.[12]《機械設計手冊》聯(lián)合編寫組. 機械設計手冊[M]. 第 2 版.北京:機械工業(yè)出版社,1987.畢 業(yè) 設 計(論 文)任 務 書5.本畢業(yè)設計(論文)課題工作進度計劃:起 迄 日 期 工 作 內 容2009 年3 月 09 日 ~ 3 月 15 日3 月 16 日 ~ 3 月 29 日3 月 30 日 ~ 4 月 19 日4 月 20 日 ~ 5 月 03 日5 月 04 日 ~ 5 月 31 日6 月 01 日 ~ 6 月 07 日6 月 08 日 ~ 6 月 14 日熟悉畢業(yè)設計要求。查閱資料,完成外文資料翻譯工作撰寫開題報告及文獻綜述尾架體加工工藝規(guī)程設計(至少提出 2 個方案,進行分析比較,最后決定一個較優(yōu)的方案)夾具設計(至少提出 2 個方案,進行分析比較,最后決定一個較優(yōu)的方案)組合機床設計(完成三圖一卡)文檔整理、撰寫畢業(yè)設計說明書。論文答辯所在專業(yè)審查意見:負責人: 2009 年 月 日系部意見:系部主任: 2009 年 月 日 南京理工大學泰州科技學院畢業(yè)設計(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: 張春雨 學 號: 05010106 外文出處: Design of the Distributed Architecture of a Machine-tool 附 件: 1.外文資料翻譯譯文;2.外文原文。指導教師評語:簽名: 年 月 日分布式機床的設計FIP現(xiàn)場總線的用途Daping SONG, Thierry DIVOUX,費朗西斯勒帕熱自動化中心研究所的Nancy摘要:本文中我們基于FIP現(xiàn)場總線上提出了一種分布式控制系統(tǒng)。它將取代傳統(tǒng)的CNC(計算機數(shù)字控制裝置)用于機床上。該系統(tǒng)是由一套以微處理機為基礎的模塊(PC機、運動控制器、I/O接口) 利用FLP實時網(wǎng)絡相互聯(lián)接的。這主要是使每個模塊智能化以提高整個系統(tǒng)的靈活性和容錯能力。每個模塊都是一個分控系統(tǒng),用于實現(xiàn)自己的分控任務,其中有些模塊用于運動控制,另一些模塊用于傳感器評價和執(zhí)行器調節(jié)。FIP決定了這些模塊之間的通訊(信息交流和同步),同時執(zhí)行任務分配以及設備布局分布。我們討論一些分布標準并描述實驗的執(zhí)行。1.引言近幾年,一直對分布式體系結構進行了許多研究。分布式體系結構在系統(tǒng)集成上發(fā)揮主要作用。在機床控制域,目前 CNC 技術有它內在的缺點。將幾根固定數(shù)量的軸容入 CIM 環(huán)境中是非常費時,靈活和不易的。超大規(guī)模集成電路微處理器技術和通信網(wǎng)絡的迅速發(fā)展使分布式控制成為可能。雖然逐步擴展沒有完全替代硬件更換但分布式控制系統(tǒng)的性能,模塊化,完整性和可靠性正在提高。它為替代控制系統(tǒng)架構提供了一個很好的前景。本文致力于對分布式機床結構的研究。它建立在智能設備與通信相聯(lián)系的基礎上。分布式機床的特點是分布式任務和分布式數(shù)據(jù),且具有獨特的控制方法。它是結合標準設備和 FIP 系統(tǒng)總線設計而成,通過實驗證明該系統(tǒng)具有可執(zhí)行性,在實驗中該系統(tǒng)控制了復合軸系,成功執(zhí)行坐標之間的關系同時也反應了對傳感器值的變化。該論文結構如下:第 2 部分描述了機床控制系統(tǒng)構架。第 3 部分簡要介紹了 FIP 現(xiàn)場總線。第 4 部分概述了我們實驗的實施。最后,我們在第 5 部分總結了一些一般性意見和今后的研究前景。2.機床控制系統(tǒng)架構該機床控制系統(tǒng)是一個實時多任務系統(tǒng)。其功能結構如圖 1 所示。它包括三種單元:用戶接口/ 監(jiān)控單元/規(guī)劃單元,伺服單元,傳感器/制動器單位。這個系統(tǒng)的主要功能是用來控制工件的加工。它包括兩個不同的和相關的任務:● 為了確保軌跡的準確性和對機床移動部件的速度控制● 為了調查定位(跟蹤)過程的正確執(zhí)行,環(huán)境變化的影響與指定操作的執(zhí)行或機床機件的運動同樣重要。例如:工具開關,冷卻,潤滑等。CAM 的制造日期圖 1:架構功能按時間順序,這項任務也可分為兩個步驟:規(guī)劃控制程序規(guī)劃和執(zhí)行控制程序。第一步,機床機件沒有直接的方向,只有運動和被指定執(zhí)行的操作,這是“數(shù)據(jù)采集和預處理”的一步。雖然在第二步,是控制的有效執(zhí)行。值得指出的是:在第二步由于多任務的性質,并行處理是可行的。3.FIP 現(xiàn)場總線FIP系統(tǒng)被用來滿足分布式機床上實時通信的需要。在這一節(jié)中,我們簡要地解釋一下FIP系統(tǒng)的技術性能。FIP(工廠儀表協(xié)議)是網(wǎng)絡系統(tǒng)用于傳感器的驅動器和控制設備如工作規(guī)劃/編程(軌跡,工具的選擇,其他加工參數(shù)采集)基本替換計算軸伺服控制系統(tǒng)機床構件傳感器/制動器環(huán)境自動安全監(jiān)測加工PLCS,CNCS或機器人控制器之間的信息交換。FIP系統(tǒng)的結構采用所謂的密封性以減少OSI模型(物理層,數(shù)據(jù)鏈路層和應用層),這種結構使實時通信和常規(guī)的信息溝通之間有明顯的區(qū)別。在數(shù)據(jù)鏈路層中,相關服務一方面與其他傳遞信息服務可變轉讓。在應用層中,我們可區(qū)分MPS服務(制造周期/非制造性規(guī)范),它采用來自數(shù)據(jù)鏈路層的信息設備所支持的MMS設備。FIP支持兩個傳輸媒體:屏蔽雙絞線和光纖。FIP允許各種各樣的布局,最長部分可達500米,至少有4個部分被中繼器代替。3種比特率被確定為:31.25k.比特/秒,1兆位/秒和2.5兆位/秒。FIP介質訪問控制是集中的。所有轉讓都由the Bus Arbiter控制,時間安排轉移必須遵守時間要求。變量和信息之間的傳遞可采用定期配置或根據(jù)站的要求來轉讓,而在我們的應用中,F(xiàn)IP只采用可變轉讓。FIP采用生產(chǎn)者和消費者的模樣來產(chǎn)生可變交流。變量對于生產(chǎn)者和消費者而言,是被確定的一個獨特的識別標志,一套制作和消費變量可以集結在一個站,但是這些識別標志不涉及任何物理地址站。圖2顯示了變化信息。廣播的 BA 標識符 認識的人 P和一些消費者?生產(chǎn)者發(fā)出的日期 P所有消費者接受的數(shù)據(jù) C 圖2:FIP系統(tǒng)的MAC圖象首先,the Bus Arbiter 廣播持有可變的標示符,所有的節(jié)點接受幀并檢查變數(shù)是生產(chǎn)還是消費產(chǎn)生的或不給予影響。第三步:作為生產(chǎn)者的站必須響應包含數(shù)據(jù)的幀。第四步:獲取消費者的變化價值并存儲。當更新產(chǎn)生時,消費者和生產(chǎn)者便形成了。FIP有兩種類型的數(shù)據(jù)交流:周期性和非周期性的。在這兩種情況下,匯率發(fā)生情況如上圖(圖2)。在第一種情況下,the Bus Arbiter根據(jù)從配置要求價值相應的標識定期轉移。第二種情況下,the Bus Arbiter 可根據(jù)現(xiàn)有的帶寬產(chǎn)生轉讓請求信號。在我們的應用中,實時的限制是非常嚴格的。為了使機床遵守給定的軌跡,軸的控制必須同步。這就要求和網(wǎng)絡連接的控制節(jié)點應該同時接受開始命令,因此網(wǎng)絡必須播出命令。為了確保相同的瞬時命令能同時被幾個接受器接受,穩(wěn)定的傳輸是非常必要的。因此,一些傳感器例如運動控制傳感器就應該要求定期調查限位開關以使網(wǎng)絡能定期無重大延誤的傳輸數(shù)據(jù)。一句話,像分布式機床的操作,像數(shù)據(jù)廣播的要求,時間和空間的一致性,定期傳輸不能滿足任何一般用途的網(wǎng)絡。然而,實時網(wǎng)絡例如FIP就是數(shù)據(jù)一種好的解決方法。4.實驗實施如圖3所示,我們的應用目標是要實現(xiàn)一個分布式的兩軸機床控制系統(tǒng)。它由以下設備分布在FIP總線的四個節(jié)點上。節(jié)點1:微機(i80486 微處理器)。它作為運營商終端。節(jié)點2.3:兩個相同的節(jié)點。每個均由微機(i80486)配備了運動控制器(克萊斯勒PCIOO + 克萊斯勒三菱商事100)。節(jié)點4:一個帶有傳感器/制動器作為輔助業(yè)務的可編程控制器(低溫100)。網(wǎng)絡:FIP和1比特/秒的雙絞線介質間的選擇。軟件架構的執(zhí)行系統(tǒng)是基于概念的多層次分布式控制。它有三種層次結構,其中第二和第三層次可實現(xiàn)分配。它包括以下層次:分析層:控制任務的執(zhí)行選擇它被映射到微機的提供用戶界面的節(jié)點上。用來處理計劃收購和儲存,不同業(yè)務模式(手動和自動模式)的交換,起始點和終點以及其它各節(jié)點之間的計算和發(fā)送。慣例層:確定某一任務的控制算法它被映射到2種其他微機上(節(jié)點2和節(jié)點3)。這兩種微機具有根據(jù)給定的參數(shù)和命令(軌跡類型,速度,加速度等)進行基本位移計算(插補)的功能。每個軸的插補算法是軟件設計的困難之一,因為軸控制分布后,每個中間坐標軸的計算是獨立的。正確的算法設計可保證這些軸的連貫性。工藝層:執(zhí)行控制它包含兩種運動:運動控制器和可編程控制器。這些設備執(zhí)行伺服系統(tǒng)運動控制,處理加工件的舉行/緊縮政策,傳感器的評定和驅動器的調節(jié)使工具切換任務和監(jiān)控系統(tǒng)更安全。為了驗證擬議的架構是否與時間限制和網(wǎng)絡能力相適應,預期流量的估計是必要的。主要有兩種性質的信息交流:● 命令從中央決定站(節(jié)點)傳到其它站?!?統(tǒng)計信息由站(節(jié)點)與站之間產(chǎn)生。例如:在我們的實驗平臺上,一些變數(shù)分布如下:節(jié)點1節(jié)點2 節(jié)點4 節(jié)點3FIP系統(tǒng) FIP系統(tǒng)運動控制 運動控制傳感器和制動器FIP 系統(tǒng) X軸 Y軸圖3:硬件執(zhí)行5.結論本文中為滿足CIM的要求,我們的研究通過實驗實施進一步達到審定。我們現(xiàn)在正致力于用來證明符合執(zhí)行實時限制的經(jīng)營架構的仿真和性能分析的工作。我們的目標不僅是一個試樣樣機,更是研究設計、優(yōu)化的分布式系統(tǒng)理論方案的發(fā)展。Design of the Distributed Architecture of a Machine-toolUsing FIP FieldbusDaping SONG, Thierry DIVOUX, Francis LEPAGECentre de Recherche en Automatique de NancyUniversite de Nancy I, BP239, 54506 Vandoeuvre-les-Nancy cedex, FranceAbstract: In this paper we propose a distributed control system based on FIP fieldbus. It is applied to machine-tool as a replacement for the traditional CNC (Computerized Numerical Controller). The system is composed of a set of microprocessor-based modules (PCs, motion controllers, I/OS, . ..) interconnected by FLP real-time network. The main idea is to enable each module to be intelligent, improving thus the flexibility and the fault tolerant capability of the whole system. Each module being a sub-control system, accomplishes its own control task, some of them for motion control and others for evaluating sensors and regulating actuators. The communication (information exchanges and synchronization) among these modules is ensured by FLP. This system allows both task distribution as well as equtpment topological distribution. We discuss some distribution criteria and describe an experimental implementation.1. IntroductionDistributed system architecture has been the subject of many research activities in recent years. It plays a major role in systems integration. In the machine-tool control domain, present CNC technology has its inherent shortcomings. It is centralized, limited to a fixed number of axis time-consuming, inflexible and difficult to be integrated in CIM environment. The rapid development of VLSI microprocessor technology and communication network enables the distributed control to be considered. Distributed control systems present the advantage of improving performance, modularity, integrity and reliability while allowing incremental expansion without complete hardware replacement. It offers a promising alternative to control system architecture.This paper is dedicated to study a distributed machine-tool architecture. It is based on intelligent devices interconnected on communication link. It is characterized by distributed tasks and distributed data, but with unique control access system. It is designed by using standard devices and FIP fieldbus and verified by a experimental implementation, in which the system controls a multi-axis machine to successfully execute a coordinated motion as well as to respond to sensors values changes.The paper is organized as follows. In section 2, the machine-tool control system architecture is described. Section 2 gives a brief description of FIP and Section 3 outlines our experimental implementation. We conclude in section 4 with some general remarks and future research perspectives.2. Machine-tool control system architectureThe machine-tool control system is a real-time and multitask system. Its classical functional architecture is shown in Fig.1. It consists of three units: user interface/supervisiou/programming unit, servo unit, and sensors/actuators unit. The main mission of this system is to control workpart machining. It includes two different and related tasks aspects: ●to ensure the precise trajectory and speed control of the mobile organs of machine-tool.●to survey the correct execution of this positioning (tracking) process, to react on environment changes as well as to perform the specified operations or actions upon machine-tool mechanics. such as tool switching, cooling, lubricating, etc. Fig. 1 Functional architectureChronologically, this mission is also divided into two steps: control program planning and control program executiug. In the first step, there is no direct action on machine-tool multitask nature: “data acquisition and preprocessing” step. While in the second step, the control is effectively executed. It is worth to note that in the second step, the parallelization is possible due to the mechanics, only the motions as well as the operations to be performed are specified. This is the “data acquisition and preprocessing” step. While in the second step, the control is effectively executed. It is worth to note that in the second step, the parallelization is possible due to themultitask nature.3.FIP fieldbusTo meet the real-time communication need in our distributed machine-tool, FIP is adopted. In this section, we briefly explain the main technical properties of FIP.FIP (Factory Instrumentation Protocol) is an industrial network designed for the exchange of information between sensors, actuators and control devices such as PLCs, CNCs or robotcontrollers. The architecture of FIP follows the so-calkd reduced OS1 model (Physical layer, Data link layer and Application layer). This architecture makes a clear distinction between real-time communication and conventional message communication. At Data Link layer, there are services associated to variable transfers on the one hand and conventional messaging services on the other hand. At Application layer, we distinguish the MPS (Manufacturing Periodic/aperiodic Specification) services which use variable transfers of Data Link layer from the MMS services which are supported by the messaging services of the Data Link layer.FlP supports two transmission media: shielded twisted pair and optical fiber. It allows for a wide variety of topologies. The maximum length of a segment is 500 m ;and at most 4 segmentsare authorized with repeaters. Three bit rates have been defined: 31.25 K.bit/s, 1 Mbit/s and 2.5 Mbit/s.FIP medium access control is centralized. All transfers are under control of the Bus Arbiter that schedules transfers to comply with timing requirements. Transfers of variables and messages may take place periodically according to system configuration or aperiodicalIy under request from any station. In our application, only variable transfer of FIP is used.For variable exchanges, FIP uses the producer-consumer model. ‘Variables are identified by a unique identifier known from the producer and the consumers. A set of produced and consumed variables can be regrouped in one station, but the identifier is not related to any physical address of stations. Fig. 2 shows the broadcast of a variable.Fig2 Principle of MAC protocol of FIPFirst, the Bus Arbiter broadcasts a frame that holds the identifier of the variable. All nodes receive the frame and check whether they are producer or consumer of the variable or not concerned. In a third step, the station that recognizes itself as the producer replies with a response frame that contains the data. In a fourth step, all the consumers of this variable capture the value and store it. The consumers and the producer are formed when the update takes place.FlP defines two types of data exchanges: periodic and aperiodic. In both cases, the exchange takes place as indicated above (Fig. 6). In the first case, the Bus Arbiter knows from the configuration that it has to request periodically the transfer of the value corresponding to an identifier. In the second case, transfer requests are signaled to the Bus Arbiter that will serve them according to the available bandwidth.For our application, the real-time constraints are very stringent. To make the machine-tool to follow an accurate trajectory, the control of the axis must be synchronized. This requires that the control nodes connected by a network should simultaneously receive the starting order, so the network should be able to broadcast orders. To ensure that an order of the same instant is received by several receivers, a spacec onsistency statue is also necessary. For responsiveness reason, some sensors like movement-limit switches should be polled periodically requiring that the network be able to transmit periodic data without important delays.In one word, for an application like distributed machine-tool, the requirements like broadcast of data , the time and space consistencies, the periodic transmission can not be met by any general-purpose networks, a real-time network like FIP is then a good solution.4. Experimental implementationAs shown in Fig. 3, our application is aiming to realize a distributed two-axis machine-tool control system. It is composed of the following devices distributed on four nodes over FIP fieldbus:node1: a microcomputer (i80486 microprocessor). It is used as operator terminal,node 2. 3: two identical nodes. Each consists of a microcomputer (i80486) equipped with a motion controller (DCX PClOO+DCX MC 100).node 4: a PLC (LT 100) with sensors/actuators for auxiliary operations.network: FIP with 1Mbits/s over twisted pair medium is chosen.The software architecture of the implemented system is based on the concept of multilayered distributed control. It has a three-level hierarchy and the distribution is realizes at the second and the third levels. It consists the following layers:Analysis layer: performs selection of the control tasksIt is mapped on to the microcomputer of node 1 which provides an user interface. It deals with the program acquisition and storage, switches the different operational modes (manual and automatic modes), computes and sends the start and arrival points coordinates as well as other orders to each other node respectively.Rule layer: determines the control algorithms for a given task.It is mapped on to the two other microcomputers (node 2 and 3) which function is elementary displacements calculation (by interpolation) according to the given parameters and orders ( trajectory type, speed, acceleration,. etc.).One of the software design difficulties is the interpolation algorithms for each axis. Because after axis control distribution, the calculation of the intermediate coordinates of each axis becomes independent, the coherence of these axis should be ensured by correct algorithm design.Process layer: executes the control.It includes the two motion controllers and the PLC. These devices executes servo systemmotion control, handles the workpart holding/tightening, tools switch tasks and monitors system safety by evaluation of sensors and regulation of actuators.In order to verify if the proposed architecture is suitable with time constraints and network capacity, in is necessary to estimate the expected traffic.There are mainly two natures of information exchanges:●orders from central decision station (node 1) to other stations.●state information produced by the stations ( node1) to other stations.For example concerning our experimental platform, we have delined some variables distributed as following:Fig3 Hardware implementation5. Conclusionln this paper, we investigated a distributed machine-tool architecture in order to meet CIM requirements. Our research reached the step of validation through the realization of anexperimental implementation. We currently work on the simulation and performance analysis of the operating architecture to justify that the implementation meets real-time constraints. Our objectiveis not only an experimental prototype, but also the development of the theoretical methodology for the design, optimization of this distributed system.
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