2個自由度搬運機械手設(shè)計二自由度直角坐標(biāo)型搬運機械手設(shè)計

PAGE專業(yè)課程設(shè)計說明書題目：搬運機械手學(xué)院（系）：專業(yè)班級：學(xué)號：10學(xué)生姓名：指導(dǎo)教師：起止時間：2013.12.12～2014.1.8

設(shè)計任務(wù)書院（系）：機械工程與自動化學(xué)院教研室：機電教研室學(xué)號學(xué)生姓名專業(yè)（班級）設(shè)計題目搬運式機械手技術(shù)參數(shù)與要求技術(shù)參數(shù)：1、抓重:19000g(夾持式手部)2、自由度數(shù):2個自由度3、坐標(biāo)型式:直角坐標(biāo)型4、橫臂手臂長度:1000mm5、手臂最大高度:1500mm要求：將工件從一個固定位置移動到另外固定位置工作量機械裝配圖一張，1#；控制電路圖一張，4#；程序流程圖一張，4#；設(shè)計計算說明書一份工作計劃查閱資料，方案討論6天方案確定1天設(shè)計計算4天繪制機械裝配圖5天控制系統(tǒng)設(shè)計，繪制電路圖3天軟件設(shè)計，繪制程序流程圖3天整理設(shè)計說明書1天答辯1天成績評定及評語圖面(45％)說明書(25％)答辯(10％)平時(20％)總分成績：指導(dǎo)教師簽字：學(xué)生簽字：年月日設(shè)計說明書38-目錄緒論………………11.1機械手的現(xiàn)狀……………………11.2選題意義…………………...…….1總體方案設(shè)計…………………...32.1研究機械手……………………….32.2機械手基本形式選擇…………….32.3總體布置設(shè)計，畫出總體布置圖………….…….4機械系統(tǒng)的設(shè)計計算…………………..………53.1.1動力電機的選擇…………….…...53.1.2械手夾持范圍設(shè)計………….……3.2.1滑動絲杠設(shè)計計算…………………….………3.2.2電機的選擇……………….…73.2.3直臂氣缸的選擇…………….…...83.2.4機械手臂設(shè)計……………….…...93.3電機聯(lián)軸器的選擇………12控制系統(tǒng)的設(shè)計………144.1控制器的選擇………………15.4.2控制器結(jié)構(gòu)…………………….…16結(jié)論………….…………………..…………17參考文獻……………………...…………….18緒論研究內(nèi)容的現(xiàn)狀能模仿人手和臂的某些動作功能，用以按固定程序抓取、搬運物件或操作工具的自動操作裝置。它可代替人的繁重勞動以實現(xiàn)生產(chǎn)的機械化和自動化，能在有害環(huán)境下操作以保護人身安全，因而廣泛應(yīng)用于機械制造、冶金、電子、輕工和原子能等部門。

機械手主要由手部和運動機構(gòu)組成。手部是用來抓持工件（或工具）的部件，根據(jù)被抓持物件的形狀、尺寸、重量、材料和作業(yè)要求而有多種結(jié)構(gòu)形式，如夾持型、托持型和吸附型等。運動機構(gòu)，使手部完成各種轉(zhuǎn)動（擺動）、移動或復(fù)合運動來實現(xiàn)規(guī)定的動作，改變被抓持物件的位置和姿勢。運動機構(gòu)的升降、伸縮、旋轉(zhuǎn)等獨立運動方式，稱為機械手的自由度。為了抓取空間中任意位置和方位的物體，需有6個自由度。自由度是機械手設(shè)計的關(guān)鍵參數(shù)。自由度越多，機械手的靈活性越大，通用性越廣，其結(jié)構(gòu)也越復(fù)雜。一般專用機械手有2～3個自由度。

機械手的種類，按驅(qū)動方式可分為液壓式、氣動式、電動式、機械式機械手；按適用范圍可分為專用機械手和通用機械手兩種；按運動軌跡控制方式可分為點位控制和連續(xù)軌跡控制機械手等。機械手通常用作機床或其他機器的附加裝置，如在自動機床或自動生產(chǎn)線上裝卸和傳遞工件，在加工中心中更換刀具等，一般沒有獨立的控制裝置。有些操作裝置需要由人直接操縱，如用于原子能部門操持危險物品的主從式操作手也常稱為機械手。成型機配置機械手,在目前普遍缺乏人力資源的大趨勢下,顯得尤為重要。具體突出了：

機械手三省、機械手三高的兩大優(yōu)勢。機械手三?。簷C械手省時、機械手省力、機械手省錢。機械手三高：機械手高效率、機械手高安全、機械手高回報。1.2選題意義目前，在國內(nèi)很多工廠的生產(chǎn)線上數(shù)控機床裝卸工件仍由人工完成，勞動強度大、生產(chǎn)效率低。為了提高生產(chǎn)加工的工作效率,降低成本,并使生產(chǎn)線發(fā)展成為柔性制造系統(tǒng),適應(yīng)現(xiàn)代自動化大生產(chǎn),針對具體生產(chǎn)工藝,利用機器人技術(shù)，設(shè)計用一臺裝卸機械手代替人工工作，以提高勞動生產(chǎn)率。

機械手是在自動化生產(chǎn)過程中使用的一種具有抓取和移動工件功能的自動化裝置，它是在機械化、自動化生產(chǎn)過程中發(fā)展起來的一種新型裝置。機械手能代替人類完成危險、重復(fù)枯燥的工作，減輕人類勞動強度，提高勞動生產(chǎn)力。機械手越來越廣泛的得到了應(yīng)用，在機械行業(yè)中它可用于零部件組裝，加工工件的搬運、裝卸，特別是在自動化數(shù)控機床、組合機床上使用更普遍。它適應(yīng)于中、小批量生產(chǎn)，可以節(jié)省龐大的工件輸送裝置，結(jié)構(gòu)緊湊，而且適應(yīng)性很強。目前我國的工業(yè)機器人技術(shù)及其工程應(yīng)用的水平和國外比還有一定的距離，應(yīng)用規(guī)模和產(chǎn)業(yè)化水平低，機械手的研究和開發(fā)直接影響到我國自動化生產(chǎn)水平的提高，從經(jīng)濟上、技術(shù)上考慮都是十分必要的。因此，進行機械手的研究設(shè)計是非常有意義的。第2章總體方案設(shè)計2.1研究機械手按坐標(biāo)形式大致可以分為以下4種:㈠直角坐標(biāo)機械手；㈡圓柱坐標(biāo)型機械手；㈢球坐標(biāo)(極坐標(biāo))型機械手；㈣多關(guān)節(jié)型機機械手；圖2.1機械手基本形式簡圖2.2確定每種運動方案表2.2機械手可能方案動作123手抓夾持絲杠螺母連桿杠桿齒輪齒條橫臂平移絲杠螺母液壓傳動氣壓缸直臂升降絲杠螺母氣壓缸齒輪齒條2.3總體布置設(shè)計，畫出總體布置圖圖2.3總體布置圖注：1—手抓夾持；2—直臂升降；3—橫臂平移2.3.1實物圖第3章機械系統(tǒng)的設(shè)計計算3.1.1動力電機的選擇表3.1.1各動作動力機參數(shù)動作型號功率P(w)轉(zhuǎn)矩T（N·mm）轉(zhuǎn)速（r/min）橫臂伸縮SGMAH-01A交流伺服電動機1009551500手抓夾緊SGMPH-02A交流伺服電動機200191035003.1.2機械手夾持范圍設(shè)計圖3.1.2手爪布置圖1．手抓夾持范圍計算加工毛坯尺寸：100X120X200毛坯質(zhì)量（以鋼材的密度計算）：18960（按最大19000g計算）裝夾深度：約75mm手爪接觸塊為橡膠，橡膠具有彈性大，定伸強度高，抗撕裂性和電絕緣性優(yōu)良，耐磨性和耐旱性良好，加工性佳等特點。3.2.1滑動絲杠設(shè)計計算設(shè)計條件：需自鎖絲杠長度220mm最大質(zhì)量共計約1700g。絲杠載荷：絲杠豎直時承受最大軸向力，G=mg(g取10N/kg)。（3-1）設(shè)計計算：牙型、材料和許用應(yīng)力采用梯形單頭螺紋螺桿材料選45鋼，調(diào)制處理，，由機械手冊查表可得許用拉應(yīng)力（3-2）手爪部分為輕載，螺母材料選耐磨鑄鐵。由機械手冊查表可得許用彎曲應(yīng)力，??；許用剪應(yīng)力由機械手冊查表可得許用壓強，取按耐磨性計算螺桿中徑由表中公式，，（3-3）采用整體螺母式，取，由GB/T5796.3-1986，可選，，，，，的梯形螺紋、中等精度。螺桿左右兩端分別采用不同的旋向，螺旋副標(biāo)記分別為：，。螺母高度，?。?-4）則螺紋圈數(shù)圈（3-5）自鎖性驗算由于單頭螺紋，導(dǎo)程，故螺紋升角為（3-6）由機械手冊查表可得鋼和耐磨鑄鐵的，取，可得（3-7），故自鎖可靠。螺桿強度校核由機械手冊查表可得，螺紋摩擦力矩，（3-8）代入以下公式得螺母螺紋強度校核因螺母材料強度低于螺桿，故只需校核螺母螺紋強度即可。由機械手冊查表可得牙根寬度（3-9），基本牙高（3-10）代入以下中的公式得效率由回轉(zhuǎn)運動轉(zhuǎn)化為直線運動時（3-11）效率取為3.2.2電機的選擇計算條件：空行程最長，夾緊時間不超過1.2s設(shè)計計算：螺母移動平均速度，（3-12）摩擦轉(zhuǎn)矩（3-13）.（3-14）故（3-15）（3-16）選用轉(zhuǎn)速為的交流電機，速比齒輪傳動效率、滑動螺旋傳動效率總效率（3-17）電機軸驅(qū)動轉(zhuǎn)矩：（3-18）電機軸輸出功率：（3-19）電機選用SGMPH-02A交流伺服電動機3.2.3直臂氣缸的選擇1.手爪及工件總質(zhì)量23100g氣缸實際軸向負(fù)載F=mg=226.38N2.氣缸平均速度v=s/t=1500/6=250mm/s（3-20）負(fù)載率0.53.氣缸理論輸出力F1=F/0.5=452.76N4.單桿雙作用氣缸理論推力F1=1/4X3.14D2PD=37.97mm（3-21）5.氣缸直徑查表選擇氣缸缸徑為40mm選擇型號為STX薄型導(dǎo)桿氣缸M40X1000MM圖3.2.3氣缸和氣缸法蘭安裝形式圖3.2.4氣缸法蘭尺寸根據(jù)圖3.2.4選擇氣缸法蘭形式及安裝尺寸。3.2.4機械手橫臂設(shè)計1.滾珠絲杠設(shè)計（1）選取的滾珠絲杠轉(zhuǎn)動系統(tǒng)為：磨制絲杠(右旋)設(shè)計后絲杠總長最大行程

支承方式為兩端固定

定位精度：

由表得，有效行程內(nèi)目標(biāo)行程公差，行程變動量由表得，任意300mm行程內(nèi)行程變動量，2π弧度內(nèi)行程變動量絲杠精度為5級，可靠性90%。

（2）計算載荷手爪氣缸部分重量（重力加速度取）軸向載荷

（3）初算導(dǎo)程：絲杠螺母轉(zhuǎn)速，直臂移動速度

初算導(dǎo)程，所以取選工作壽命：（5）由表得，，（3-22）式中，查機械手冊得，精度系數(shù)查機械手冊得，可靠性系數(shù)查機械手冊得，載荷性質(zhì)系數(shù)查機械手冊得，預(yù)加載荷系數(shù)所以，靜載計算：由機械手冊得，，式中（7）選取滾珠絲杠型號：采用外循環(huán)導(dǎo)珠管埋入式CDM1605-3-P8型，。其中，，，，滿足承載能力要求。（8）計算預(yù)緊力：，（3-23）（9）值校驗由機械手冊得，，符合要求。（10）臨界轉(zhuǎn)速校核查機械手冊得，滿足轉(zhuǎn)速要求螺桿強度：螺桿材料為45鋼，調(diào)質(zhì)處理，其許用應(yīng)力螺桿當(dāng)量應(yīng)力：（3-24）（3-25）符合強度要求(12)系統(tǒng)剛度計算剛性為機械剛度的指標(biāo)，滾珠絲杠的剛性取決于螺桿與螺母之間軸向負(fù)荷珠槽接觸剛性及螺桿軸的剛性來決定。機械驅(qū)動系統(tǒng)總剛性的慣性經(jīng)由測試，可將螺帽—螺桿及鋼珠—珠槽兩者間的剛性合二為一，成為螺帽剛性，因此（3-26）（3-27）（3-28）2.電機選型計算條件：絲杠軸向工作載荷約為，絲杠移動速度聯(lián)軸器傳遞效率軸承傳遞效率設(shè)計計算：絲杠工作的功率：（3-29）絲杠轉(zhuǎn)矩電機選用同步轉(zhuǎn)速交流伺服電動機電機輸出軸負(fù)載轉(zhuǎn)矩：電機輸出軸功率電機選用SGMAH-01A交流伺服電動機3.3電機聯(lián)軸器的選擇根據(jù)電機軸軸徑為15mm,滾珠絲杠軸端軸徑為15mm，回轉(zhuǎn)間隙為±0.001mm,導(dǎo)軌工字導(dǎo)軌上下面平度誤差±0.00017mm,徑向偏差±0.0028mm，角向偏差±0.003mm,選擇TGD-S40-15-15型聯(lián)軸器。4.橫臂導(dǎo)軌與滑塊選擇根據(jù)表3.4選擇SME20EASME20LEA型導(dǎo)軌和滑塊。表3.3滑軌尺寸表高W1寬H1節(jié)距P動負(fù)荷kN靜負(fù)載kN靜容許力矩Mp靜容許力矩My靜容許力矩Mr導(dǎo)軌質(zhì)量Kg滑塊質(zhì)量Kg/mSME2015.56020.432.10.27KN-m0.27KN-m0.33KN-m0.422.3控制系統(tǒng)的設(shè)計4.1控制器的選擇搬運機械手的電控部分選擇PLC控制，因為PLC介于工業(yè)控制計算機和可編程控制器之間，他有較強的控制功能和低廉的成本，具有小巧靈活、成本低、易于產(chǎn)品化、可靠性好、適應(yīng)溫度范圍寬、易擴展、控制功能強等優(yōu)點，所以在電氣傳動實時控制系統(tǒng)中受到重視和普遍應(yīng)用。人們在選擇電動機的控制器時，常常是在先滿足功能需要的同時，優(yōu)先選擇成本低的控制器。因此，PLC往往成為優(yōu)先選擇的目標(biāo)，PLC是目前世界上使用量最大的微處理器。51系列單片機、PLC單片機的應(yīng)用廣泛，有很多優(yōu)點，其如下所訴：PLC價格便宜。適用于小型自動控制領(lǐng)域及無線控制領(lǐng)域；2.易學(xué)易用，深受工程技術(shù)人員歡迎；3.配套齊全，功能完善，適用性強。本機器需要控制2個電機。首先控制交流伺服電機啟動，觸碰到形程開關(guān)，電機制動，手部的伺服電機啟動，夾取物品，當(dāng)傳感器檢測到手夾取物品時會給單片機發(fā)出信號，單片機收到信號后會控制電機的啟停，然后運送到下一位置，手部電機啟動，放下工件。8031單片機需要控制兩個步進電機，因此除了需要擴展程序存儲器和數(shù)據(jù)存儲器外，還需要擴展I/O口,用8155擴展單片機的I/O口，8155的輸出接口連接兩個步進電機的驅(qū)動芯片L6208，由以上設(shè)計要求得出流程圖如下：4.2控制流程圖圖4.3械手流程圖4.3驅(qū)動器結(jié)構(gòu)圖4.3驅(qū)動器結(jié)構(gòu)第5章總結(jié)經(jīng)過兩周的努力終于完成了課程設(shè)計設(shè)計，由于經(jīng)驗的匱乏，難免有許多考慮不周全的地方，如果沒有導(dǎo)師的督促指導(dǎo)，以及一起工作的同學(xué)們的支持，想要完成這次設(shè)計任務(wù)是難以想象的。本次課程設(shè)計是在董老師的精心指導(dǎo)下完成的，雖然他平日里工作繁多，但在我做課程設(shè)計設(shè)計的每個階段，設(shè)計整個過程中吳老師都給予了我悉心的指導(dǎo)，他的治學(xué)嚴(yán)謹(jǐn)和科學(xué)研究的精神也是我永遠(yuǎn)學(xué)習(xí)的榜樣，并將積極影響我今后的學(xué)習(xí)和工作。同時感謝和我一起并肩奮戰(zhàn)的同學(xué)們，在我課程設(shè)計過程中對我的悉心指導(dǎo)，他們在設(shè)計過程中給與了我很大的幫助。正是有了互相的支持和鼓勵，才得以順利完成此次課程設(shè)計。通過本次設(shè)計使我加深了對PLC的理解，擴大和深化了專業(yè)知識面。因此我們只有通過不斷加強學(xué)習(xí)，才能提高適應(yīng)現(xiàn)代技術(shù)發(fā)展的能力和要求。另外，課堂上也有部分知識不太清楚，于是我又不得不邊學(xué)邊用，時刻鞏固所學(xué)知識，這也是我作本次課程設(shè)計的第二大收獲。整個設(shè)計我基本上還滿意，由于水平有限，難免會有錯誤，還望老師批評指正。希望答辯時，老師多提些問題，由此我可用更好地了解到自己的不足，以便課后加以彌補。參考文獻[1]張龍.機械設(shè)計手冊[S].北京：國防工業(yè)出版社,2006,5.[2]卜炎.機械傳動裝置設(shè)計手冊[S].北京：機械工業(yè)出版社，1999,4.[3]吳宗澤.機械設(shè)計實用手冊[S].北京：化工工業(yè)出版社，2003,6.[4]成大先.機械設(shè)計手冊[S].北京：化工工業(yè)出版社，2004,1.[5]鞏云鵬.機械設(shè)計課程設(shè)計[M].沈陽：東北大學(xué)出版社，2000,12.[6]于夢生.機械零部件手冊[S].北京：機械工業(yè)出版社，1996,11.[7]孫志禮.機械設(shè)計[M].沈陽：東北大學(xué)出版社，2000,9.[8廖常初《PLC程與應(yīng)用》機械工業(yè)出版社2005年5月.[9]吳宗澤,羅圣國.機械設(shè)計課程設(shè)計手冊[M].北京：高等教育出版社，2006ONE、PLCoverviewProgrammablecontrolleristhefirstinthelate1960sintheUnitedStates,thencalledPLCprogrammablelogiccontroller(ProgrammableLogicController)isusedtoreplacerelays.Fortheimplementationofthelogicaljudgment,timing,sequencenumber,andothercontrolfunctions.TheconceptispresentedPLCGeneralMotorsCorporation.PLCandthebasicdesignisthecomputerfunctionalimprovements,flexible,genericandotheradvantagesandrelaycontrolsystemsimpleandeasytooperate,suchastheadvantagesofcheappricescombinedcontrollerhardwareisstandardandoverall.Accordingtothepracticalapplicationoftargetsoftwareinordertocontrolthecontentoftheuserproceduresmemorycontroller,thecontrollerandconnectingtheaccusedconvenienttarget.Inthemid-1970s,thePLChasbeenwidelyusedasacentralprocessingunitmicroprocessor,importexportmoduleandtheexternalcircuitsareused,large-scaleintegratedcircuitsevenwhenthePLCisnolongertheonlylogical(IC)judgmentfunctionsalsohavedataprocessing,PIDconditioninganddatacommunicationsfunctions.InternationalElectrotechnicalCommission(IEC)standardspromulgatedprogrammablecontrollerforprogrammablecontrollerdraftmadethefollowingdefinition:programmablecontrollerisadigitalelectroniccomputersoperatingsystem,specificallyforapplicationsintheindustrialdesignenvironment.Itusedprogrammablememory,usedtoimplementlogicintheirinternalstorageoperations,sequencecontrol,timing,countingandarithmeticoperations,suchasoperatinginstructions,andthroughdigitalandanaloginputandoutput,thecontrolofvarioustypesofmachineryorproductionprocesses.Programmablecontrollerandrelatedperipherals,andindustrialcontrolsystemseasilylinkedtoformawhole,toexpanditsfunctionaldesign.Programmablecontrollerfortheuser,isanon-contactequipment,theprocedurescanbechangedtochangeproductionprocesses.Theprogrammablecontrollerhasbecomeapowerfultoolforfactoryautomation,widelypopularreplication.Programmablecontrollerisuser-orientedindustriesdedicatedcontrolcomputer,withmanydistinctivefeatures.First,highreliability,anti-interferencecapability;Second，programmingvisual,simple;Third,adaptabilitygood;Fourthfunctionalimprovements,strongfunctionalinterface.TWO、HistoryofPLCProgrammableLogicControllers(PLC),acomputingdeviceinventedbyRichardE.Morleyin1968,havebeenwidelyusedinindustryincludingmanufacturingsystems,transportationsystems,chemicalprocessfacilities,andmanyothers.Atthattime,thePLCreplacedthehardwiredlogicwithsoft-wiredlogicorso-calledrelayladderlogic(RLL),aprogramminglanguagevisuallyresemblingthehardwiredlogic,andreducedtherebytheconfigurationtimefrom6monthsdownto6days[MoodyandMorley,1999].AlthoughPCbasedcontrolhasstartedtocomeintoplace,PLCbasedcontrolwillremainthetechniquetowhichthemajorityofindustrialapplicationswilladhereduetoitshigherperformance,lowerprice,andsuperiorreliabilityinharshenvironments.Moreover,accordingtoastudyonthePLCmarketofFrostandSullivan[1995],anincreaseoftheannualsalesvolumeto15millionPLCsperyearwiththehardwarevalueofmorethan8billionUSdollarshasbeenpredicted,thoughthepricesofcomputinghardwareissteadilydropping.TheinventorofthePLC,RichardEMorley,fairlyconsidersthePLCmarketasa5-billionindustryatthepresenttime.ThoughPLCsarewidelyusedinindustrialpractice,theprogrammingofPLCbasedcontrolsystemsisstillverymuchrelyingontrial-and-error.Alikesoftwareengineering,PLCsoftwaredesignisfacingthesoftwaredilemmaorcrisisinasimilarway.Morleyhimselfemphasizedthisaspectmostforcefullybyindicating`Ifhouseswerebuiltlikesoftwareprojects,asinglewoodpeckercoulddestroycivilization.”Particularly,practicalproblemsinPLCprogrammingaretoeliminatesoftwarebugsandtoreducethemaintenancecostsofoldladderlogicprograms.ThoughthehardwarecostsofPLCsaredroppingcontinuously,reducingthescantimeoftheladderlogicisstillanissueinindustrysothatlow-costPLCscanbeused.Ingeneral,theproductivityingeneratingPLCisfarbehindcomparedtootherdomains,forinstance,VLSIdesign,whereefficientcomputeraideddesigntoolsareinpractice.ExistentsoftwareengineeringmethodologiesarenotnecessarilyapplicabletothePLCbasedsoftwaredesignbecausePLC-programmingrequiresasimultaneousconsiderationofhardwareandsoftware.Thesoftwaredesignbecomes,thereby,moreandmorethemajorcostdriver.Inmanyindustrialdesignprojects,morethanofthemanpowerallocatedforthecontrolsystemdesignandinstallationisscheduledfortestinganddebuggingPLCprograms.Inaddition,currentPLCbasedcontrolsystemsarenotproperlydesignedtosupportthegrowingdemandforflexibilityandreconfigurabilityofmanufacturingsystems.Afurtherproblem,impellingtheneedforasystematicdesignmethodology,istheincreasingsoftwarecomplexityinlarge-scaleprojects.TheobjectiveofthisthesisistodevelopasystematicsoftwaredesignmethodologyforPLCoperatedautomationsystems.Thedesignmethodologyinvolveshigh-leveldescriptionbasedonstatetransitionmodelsthattreatautomationcontrolsystemsasdiscreteeventsystems,astepwisedesignprocess,andsetofdesignrulesprovidingguidanceandmeasurementstoachieveasuccessfuldesign.Thetangibleoutcomeofthisresearchistofindawaytoreducetheuncertaintyinmanagingthecontrolsoftwaredevelopmentprocess,thatis,reducingprogramminganddebuggingtimeandtheirvariation,increasingflexibilityoftheautomationsystems,andenablingsoftwarereusabilitythroughmodularity.Thegoalistoovercomeshortcomingsofcurrentprogrammingstrategiesthatarebasedontheexperienceoftheindividualsoftwaredeveloper.Three、nowofPLCFromthestructureisdividedintofixedPLCandModulePLC,thetwokindsofPLCincludingCPUboard,I/Oboard,displaypanel,memoryblock,power,theseelementsintoadonotremoveoverall.ModuletypePLCincludingCPUmodule,I/Omodules,memory,thepowermodules,bottomoraframe,thesemodulescanbeaccordingtocertainrulescombinationconfiguration.Intheuserview,adetailedanalysisoftheCPU'sinternalunnecessary,butworkingmechanismofeverypartofthecircuit.TheCPUcontrolworks,byitreadsCPUinstruction,interpretstheinstructionandexecutesinstructions.Butthepaceofworkbyshocksignalcontrol.Unitworkunderthecontrollercommandusedinadigitalorlogicoperation.Incomputingandstorageregisterofcomputationresult,itisalsoamongthecontrollercommandandwork.CPUspeedandmemorycapacityistheimportantparametersforPLC,itsdeterminesthePLCspeedofwork,IOPLCnumberandsoftwarecapacity,solimitstocontrolsize.CentralProcessingUnit(CPU)isthebrainofaPLCcontroller.CPUitselfisusuallyoneofthemicrocontrollers.Aforetimethesewere8-bitmicrocontrollerssuchas8051,andnowtheseare16-and32-bitmicrocontrollers.Unspokenruleisthatyou’llfindmostlyHitachiandFujicumicrocontrollersinPLCcontrollersbyJapanesemakers,SiemensinEuropeancontrollers,andMotorolamicrocontrollersinAmericanones.CPUalsotakescareofcommunication,interconnectednessamongotherpartsofPLCcontrollers,programexecution,memoryoperation,overseeinginputandsettingupofanoutput.Systemmemory(todaymostlyimplementedinFLASHtechnology)isusedbyaPLCforaprocesscontrolsystem.Asideform.thisoperatingsystemitalsocontainsauserprogramtranslatedformaladderdiagramtoabinaryform.FLASHmemorycontentscanbechangedonlyincasewhereuserprogramisbeingchanged.PLCcontrollerswereusedearlierinsteadofPLASHmemoryandhavehadEPROMmemoryinsteadofFLASHmemorywhichhadtobeerasedwithUVlampandprogrammedonprogrammers.WiththeuseofFLASHtechnologythisprocesswasgreatlyshortened.Reprogrammingaprogrammemoryisdonethroughaserialcableinaprogramforapplicationdevelopment.Usermemoryisdividedintoblockshavingspecialfunctions.Somepartsofamemoryareusedforstoringinputandoutputstatus.Therealstatusofaninputisstoredeitheras“1”oras“0”inaspecificmemorybit/eachinputoroutputhasonecorrespondingbitinmemory.Otherpartsofmemoryareusedtostorevariablecontentsforvariablesusedinusedprogram.Forexample,timevalue,orcountervaluewouldbestoredinthispartofthememory.PLCcontrollercanbereprogrammedthroughacomputer(usualway),butalsothroughmanualprogrammers(consoles).ThispracticallymeansthateachPLCcontrollercanprogrammedthroughacomputerifyouhavethesoftwareneededforprogramming.Today’stransmissioncomputersareidealforreprogrammingaPLCcontrollerinfactoryitself.Thisisofgreatimportancetoindustry.Oncethesystemiscorrected,itisalsoimportanttoreadtherightprogramintoaPLCagain.ItisalsogoodtocheckfromtimetotimewhetherprograminaPLChasnotchanged.Thishelpstoavoidhazardoussituationsinfactoryrooms(someautomakershaveestablishedcommunicationnetworkswhichregularlycheckprogramsinPLCcontrollerstoensureexecutiononlyofgoodprograms).AlmosteveryprogramforprogrammingaPLCcontrollerpossessesvarioususefuloptionssuchas:forcedswitchingonandoffofthesysteminput/outputs(I/Olines),programfollowupinrealtimeaswellasdocumentingadiagram.Thisdocumentingisnecessarytounderstandanddefinefailuresandmalfunctions.Programmercanaddremarks,namesofinputoroutputdevices,andcommentsthatcanbeusefulwhenfindingerrors,orwithsystemmaintenance.Addingcommentsandremarksenablesanytechnician(andnotjustapersonwhodevelopedthesystem)tounderstandaladderdiagramrightaway.Commentsandremarkscanevenquotepreciselypartnumbersifreplacementswouldbeneeded.Thiswouldspeeduparepairofanyproblemsthatcomeupduetobadparts.Theoldwaywassuchthatapersonwhodevelopedasystemhadprotectionontheprogram,sonobodyasidefromthispersoncouldunderstandhowitwasdone.Correctlydocumentedladderdiagramallowsanytechniciantounderstandthoroughlyhowsystemfunctions.Electricalsupplyisusedinbringingelectricalenergytocentralprocessingunit.MostPLCcontrollersworkeitherat24VDCor220VAC.OnsomePLCcontrollersyou’llfindelectricalsupplyasaseparatemodule.ThoseareusuallybiggerPLCcontrollers,whilesmallandmediumseriesalreadycontainthesupplymodule.UserhastodeterminehowmuchcurrenttotakefromI/Omoduletoensurethatelectricalsupplyprovidesappropriateamountofcurrent.Differenttypesofmodulesusedifferentamountsofelectricalcurrent.Thiselectricalsupplyisusuallynotusedtostartexternalinputoroutput.UserhastoprovideseparatesuppliesinstartingPLCcontrollerinputsbecausethenyoucanensuresocalled“pure”supplyforthePLCcontroller.Withpuresupplywemeansupplywhereindustrialenvironmentcannotaffectitdamagingly.SomeofthesmallerPLCcontrollerssupplytheirinputswithvoltagefromasmallsupplysourcealreadyincorporatedintoaPLC.Four、PLCdesigncriteriaAsystematicapproachtodesigningPLCsoftwarecanovercomedeficienciesinthetraditionalwayofprogrammingmanufacturingcontrolsystems,andcanhavewideramificationsinseveralindustrialapplications.Automationcontrolsystemsaremodeledbyformallanguagesor,equivalently,bystatemachines.Formalrepresentationsprovideahigh-leveldescriptionofthebehaviorofthesystemtobecontrolled.Statemachinescanbeanalyticallyevaluatedastowhetherornottheymeetthedesiredgoals.Secondly,astatemachinedescriptionprovidesastructuredrepresentationtoconveythelogicalrequirementsandconstraintssuchasdetailedsafetyrules.Thirdly,well-definedcontrolsystemsdesignoutcomesareconducivetoautomaticcodegeneration-Anabilitytoproducecontrolsoftwareexecutableoncommercialdistinctlogiccontrollerscanreduceprogramminglead-timeandlaborcost.Inparticular,thethesisisrelevantwithrespecttothefollowingaspects.Inmodernmanufacturing,systemsarecharacterizedbyproductandprocessinnovation,becomecustomer-drivenandthushavetorespondquicklytochangingsystemrequirements.Amajorchallengeisthereforetoprovideenablingtechnologiesthatcaneconomicallyreconfigureautomationcontrolsystemsinresponsetochangingneedsandnewopportunities.Designandoperationalknowledgecanbereusedinreal-time,therefore,givingasignificantcompetitiveedgeinindustrialpractice.Studieshaveshownthatprogrammingmethodologiesinautomationsystemshavenotbeenabletomatchrapidincreaseinuseofcomputingresources.Forinstance,theprogrammingofPLCsstillreliesonaconventionalprogrammingstylewithladderlogicdiagrams.Asaresult,thedelaysandresourcesinprogrammingareamajorstumblingstonefortheprogressofmanufacturingindustry.Testinganddebuggingmayconsumeover50%ofthemanpowerallocatedforthePLCprogramdesign.Standards[IEC60848,1999;IEC-61131-3,1993;IEC61499,1998;ISO15745-1,1999]havebeenformedtofixanddisseminatestate-of-the-artdesignmethods,buttheynormallycannotparticipateinadvancingtheknowledgeofefficientprogramandsystemdesign.Asystematicapproachwillincreasethelevelofdesignautomationthroughreusingexistingsoftwarecomponents,andwillprovidemethodstomakelarge-scalesystemdesignmanageable.Likewise,itwillimprovesoftwarequalityandreliabilityandwillberelevanttosystemshighsecuritystandards,especiallythosehavinghazardousimpactontheenvironmentsuchasairportcontrol,andpublicrailroads.Thesoftwareindustryisregardedasaperformancedestructorandcomplexitygenerator.Steadilyshrinkinghardwarepricesspoilstheneedforsoftwareperformanceintermsofcodeoptimizationandefficiency.Theresultisthatmassiveandlessefficientsoftwarecodeononehandoutpacesthegainsinhardwareperformanceontheotherhand.Secondly,softwareproliferatesintocomplexityofunmanageabledimensions;softwareredesignandmaintenance-essentialinmodernautomationsystems-becomesnearlyimpossible.Particularly,PLCprogramshaveevolvedfromacouplelinesofcode25yearsagotothousandsoflinesofcodewithasimilarnumberof1/Opoints.Increasedsafety,forinstancenewpoliciesonfireprotection,andtheflexibilityofmodernautomationsystemsaddcomplexitytotheprogramdesignprocess.Consequently,thelife-cyclecostofsoftwareisapermanentlygrowingfractionofthetotalcost.80-90%ofthesecostsaregoingintosoftwaremaintenance,debugging,adaptationandexpansiontomeetchangingneeds.Today,theprimaryfocusofmostdesignresearchisbasedonmechanicalorelectricalproducts.Oneoftheby-productsofthisproposedresearchistoenhanceourfundamentalunderstandingofdesigntheoryandmethodologybyextendingittothefieldofengineeringsystemsdesign.Asystemdesigntheoryforlarge-scaleandcomplexsystemisnotyetfullydeveloped.Particularly,thequestionofhowtosimplifyacomplicatedorcomplexdesigntaskhasnotbeentackledinascientificway.Furthermore,buildingabridgebetweendesigntheoryandthelatestepistemologicaloutcomesofformalrepresentationsincomputersciencesandoperationsresearch,suchasdiscreteeventsystemmodeling,canadvancefuturedevelopmentinengineeringdesign.Fromalogicalperspective,PLCsoftwaredesignissimilartothehardwaredesignofintegratedcircuits.ModernVLSIdesignsareextremelycomplexwithseveralmillionpartsandaproductdevelopmenttimeof3years[Whitney,1996].Thedesignprocessisnormallyseparatedintoacomponentdesignandasystemdesignstage.Atcomponentdesignstage,singlefunctionsaredesignedandverified.Atsystemdesignstage,componentsareaggregatedandthewholesystembehaviorandfunctionalityistestedthroughsimulation.Ingeneral,acompleteverificationisimpossible.Hence,asystematicapproachasexemplifiedforthePLCprogramdesignmayimpactthelogicalhardwaredesign.Five、AK1703ACPFollowingtheprincipleofourproductdevelopment,AK1703ACPhashighfunctionalityandflexibility,throughtheimplementationofinnovativeandreliabletechnologies,onthestablebasisofareliableproductplatform.Forthis,thesystemconceptACP(Automation,ControlandProtection)createsthetechnologicalpreconditions.Balancedfunctionalitypermitstheflexiblecombinationofautomation,telecontrolandcommunicationtasks.Complementedwiththescalableperformanceandvariousredundancyconfigurations,anoptimaladaptationtotherespectiverequirementsoftheprocessisachieved.AK1703ACPisthusperfectlysuitableforautomationwithintegratedtelecontroltechnologyas:?Telecontrolsubstationorcentraldevice?Automationunitwithautonomousfunctionalgroups?Datanode,stationcontroldevice,front-endorgateway?Withlocalorremoteperipherals?Forrearpanelinstallationor19inchassembly?Branch-neutralproduct,thereforeversatilefieldsofapplicationandhighproductstability?Versatilecommunication?Easyengineering?Plug&playforspareparts?Opensystemarchitecture?Scalableredundancy?Theintelligentterminal-TM1703TheBaseUnitAK1703ACPwithPeripheralElementshasonebasicsystemelementCP-2010/CPC25(Mastercontrolelement)andCP-2012/PCCE25(Processingandcommunicationelement),onebuslinewithmax.16peripheralelementscanbeconnected.CP-2010/CPC25FeaturesandFunctionsSystemFunctions:?Centralelement,coordinatingallsystemservicesCentralhubfunctionforallconnectedbasicsystemelements?TimemanagementCentralclockoftheautomationunitSettingandkeepingtheownclock`stimewitharesolutionof10msSynchronizationviaseridcommunicationviaLANorlocal?RedundancyVotingandchange-overforredundantprocessingandcommunicationelementsoftheownautomationunitSupportsvotingandchange-overbyanexternalSCA-RSredundancyswitchSupportsapplicationalvotingandchange-overbyanexternalsystem,e.g.acontrolsystem?SATTOLLBOX||connectionStoringfirmwareandparametersonaFlashCardCommunication:?Communicationviainstallableprotocolelementstoanysuperiororsubordinateautomationunit?Automaticdataflowrouting?Prioritybaseddatatransmission(prioritycontrol)?Owncircularbufferandprocessimageforeachconnectedstation(datakeeping)?RedundantcommunicationroutesCommunicationwithredundantremotestations?Specialapplicationspecificfunctionsfordial-uptrafficTestifstationsarereachableProcessPeripherals:?Transmissionofspontaneousinformationobjectsfromandtoperipheralelements,viatheserialAx1703peripheralbusFunctionsforAutomation:?Open-/closed-loopcontrolfunctionfortheexecutionoffreelydefinableuserprogramswhicharecreatedwithCAEXplusaccordingtoIEC61131-3,e.g.usingfunctiondiagramtechnology512KBforuserprogramApprox50.000variablesandsignals,2.000ofthemretainedCycleof10msoramultiplethereofOnlinetestLoadablewithoutserviceinterruption?Redundantopen-/closed-loopcontrolfunctionsSynchronizati