2291 變速器換擋叉加工工藝及關(guān)鍵工序工裝設(shè)計(jì)
2291 變速器換擋叉加工工藝及關(guān)鍵工序工裝設(shè)計(jì),變速器,換擋,加工,工藝,關(guān)鍵,癥結(jié),樞紐,工序,工裝,設(shè)計(jì)
南京理工大學(xué)泰州科技學(xué)院畢業(yè)設(shè)計(jì)(論文)外文資料翻譯系 部: 機(jī)械工程 專 業(yè): 機(jī)械工程及自動(dòng)化 姓 名: 施道偉 學(xué) 號(hào): 0501510132 外文出處: http://user.qzone.qq.com/ 493114916?ptlang=2052 附 件: 1.外文資料翻譯譯文;2.外文原文。 指導(dǎo)教師評(píng)語(yǔ):簽名: 年 月 日注:請(qǐng)將該封面與附件裝訂成冊(cè)。(用外文寫)附件 1:外文資料翻譯譯文 機(jī)器人機(jī)器人可以界定一種由電子、電氣或機(jī)械單位組成的可編程、自動(dòng)控制裝置。更一般地說(shuō),它是一種職能到位的生活智能機(jī)器,機(jī)器人尤其可取的是某些工作職能。它他們和人類不同,他們不會(huì)感到疲憊和厭倦,可以在環(huán)境條件差和真空,甚至是危險(xiǎn)的環(huán)境下工作,他們不會(huì)因?yàn)橐晃兜刂貜?fù)工作感到厭倦放下手邊的工作。機(jī)器人不同于一般機(jī)械設(shè)備的特征是機(jī)器人可以自己進(jìn)行工作,并對(duì)內(nèi)外部的工作狀況進(jìn)行檢測(cè),將檢測(cè)到的結(jié)果反饋給控制系統(tǒng),由控制系統(tǒng)下達(dá)命令來(lái)調(diào)整下一步的動(dòng)作,更為重要的是機(jī)器人往往有能力去嘗試不同的方法來(lái)完成某項(xiàng)任務(wù)。常見(jiàn)的工業(yè)機(jī)器人由于受到制造精度的限制,他們的外型看上去都非常的龐大和笨重,機(jī)器人在程序的控制下進(jìn)行高效和高精度的工作。有人估計(jì)在1998 年有 72 萬(wàn)臺(tái)工業(yè)機(jī)器人被應(yīng)用到生產(chǎn)中??赏ㄐ艡C(jī)器人被用在海底和核設(shè)施等半結(jié)構(gòu)化的環(huán)境中,他們?cè)谀抢飶氖路侵貜?fù)性任務(wù),時(shí)間也沒(méi)有太大的限制。“機(jī)器人”在古時(shí)候是指的是一個(gè)人,現(xiàn)代“機(jī)器人”一詞最早出現(xiàn)在 20 世紀(jì)的捷克語(yǔ)中,在捷克語(yǔ)中機(jī)器人的意思是奴隸、仆人或被強(qiáng)迫工作的勞動(dòng)力。 機(jī)器人與人有很大的區(qū)別,但他們也非常的靈活,能夠完成各種不同的工作。據(jù)劇作家卡雷爾. 卡培科介紹,最初的機(jī)器人就像弗蘭肯斯坦博士的怪物--不是用機(jī)械式的方法,而是有化學(xué)和生物的原理造出來(lái)。從這些最初的生物創(chuàng)作來(lái)看,這和目前的機(jī)械機(jī)器人流行文化沒(méi)有多大不同。目前機(jī)器人領(lǐng)域已經(jīng)有了許許多多的具有基本物理和導(dǎo)航能力機(jī)器人,同時(shí),人們也開(kāi)始將機(jī)器人運(yùn)用于從娛樂(lè)到衛(wèi)生保健等各個(gè)部門的日常生活中,進(jìn)而完全取代人類。許多愛(ài)好智能機(jī)器人的研究者正在不遺余力的進(jìn)行機(jī)器人的設(shè)計(jì)。此外,機(jī)器人可用于更普遍的工作。例如清潔衛(wèi)生的工作。然而發(fā)明機(jī)器人的最初目的是代替人類在骯臟、枯燥和危險(xiǎn)下進(jìn)行工作,可是現(xiàn)在他們現(xiàn)被當(dāng)作個(gè)人助理。隨著科學(xué)技術(shù)發(fā)展到一個(gè)新的境界,機(jī)器人將會(huì)具有更多的智慧,對(duì)人類的未來(lái)產(chǎn)生重大影響?,F(xiàn)代機(jī)器人主要包括: 機(jī)械裝置,如用輪式平臺(tái)、手臂或其它部件,能夠在一定的空間范圍內(nèi)運(yùn)動(dòng)。傳感器及其周邊設(shè)備,能夠?qū)χ車沫h(huán)境狀況做出檢測(cè),進(jìn)而送入反饋裝置??刂葡到y(tǒng)將傳送過(guò)來(lái)的信息進(jìn)行分析和計(jì)算,通過(guò)指令使裝置做出調(diào)整適應(yīng)環(huán)境的改變。機(jī)械平臺(tái)-- 硬件部分 :機(jī)器人主要分為兩部分,機(jī)器人的身體和某種形式的人工智能(AI )系統(tǒng),不同的身體部分也可以稱為機(jī)器人。例如機(jī)器人手臂被用來(lái)焊接和油漆,有的機(jī)器人能夠運(yùn)送零件和在地球深層探礦。通常機(jī)器人最讓人感興趣的是它的行為,要一些人工智能。最簡(jiǎn)單的行為是機(jī)器人的定點(diǎn)運(yùn)動(dòng),典型的是車輪被用做底部支撐和傳動(dòng)裝置,在動(dòng)力系統(tǒng)的指令下使機(jī)器人從一點(diǎn)運(yùn)動(dòng)到另一點(diǎn)。電機(jī):各種電動(dòng)馬達(dá)提供電力給機(jī)器人,讓他們?nèi)ミ\(yùn)送材料、零件、工具或?qū)S醚b置。電機(jī)的效率等級(jí)表示電量轉(zhuǎn)化成機(jī)械能的能力。傳動(dòng)裝置: 齒輪和鏈條是機(jī)械的傳動(dòng)平臺(tái),它提供了強(qiáng)大而準(zhǔn)確的從一個(gè)地方到另一個(gè)地方的傳送旋轉(zhuǎn)運(yùn)動(dòng)。變速的大小取決于兩齒輪的齒數(shù),當(dāng)主動(dòng)齒輪旋轉(zhuǎn)一周,被動(dòng)齒輪也轉(zhuǎn)動(dòng)一周。電源: 電源供應(yīng)器通常是兩種類型的電池 .主要電池只能使用一次,然后丟棄。次要電池大部分是通過(guò)可變的化學(xué)反應(yīng)產(chǎn)生電能,進(jìn)而反復(fù)利用,直到內(nèi)部的化學(xué)物質(zhì)不能產(chǎn)生電能。主要電池具有很多的物質(zhì)和較低的自利用率。次要電池的能源物質(zhì)比一次性電池少,但這種電池的電能可高達(dá)一千倍,這取決于其化學(xué)反應(yīng)及其所在的環(huán)境。通常首次使用充電電池只能夠提供 4 個(gè)小時(shí)的連續(xù)運(yùn)行的能量,有數(shù)百種不同類型的電池可供機(jī)器人使用。電池可按其化學(xué)成分、大小、額定電壓和容量來(lái)進(jìn)行分類。不同的額定電壓和能量適用于不同的機(jī)器人,這要根據(jù)機(jī)器人所要完成的工作來(lái)選擇。通常機(jī)器人都用來(lái)兩個(gè)電池組來(lái)供電,他們共用一個(gè)底部,當(dāng)電機(jī)污染了其中一個(gè)電池時(shí)另一個(gè)電池會(huì)在電子系統(tǒng)的控制下自動(dòng)關(guān)閉,這兩個(gè)電池還能夠?yàn)殡姍C(jī)和電子系統(tǒng)提供不同的電壓。電子控制: 機(jī)器人有兩個(gè)主要的硬件平臺(tái),機(jī)械平臺(tái)沒(méi)有電壓、電力和反電動(dòng)勢(shì)。電子平臺(tái)有干凈的電源和五伏電壓。這兩個(gè)平臺(tái)需要通過(guò)一定的數(shù)字邏輯控制聯(lián)系起來(lái)。電子元件是連接的橋梁,控制信號(hào)在繼電器的線圈周圍產(chǎn)生磁場(chǎng),關(guān)閉開(kāi)關(guān)。舉例來(lái)說(shuō),高效率的硅開(kāi)關(guān),可以作為靜態(tài)繼電器控制機(jī)械系統(tǒng)控制元件。在另一方面,較大規(guī)模的機(jī)器人可能需要 PMDC 電源,其中 MOSFET 的"on"電阻,在散熱芯片產(chǎn)生的熱量下會(huì)急劇的增加,這就需要大大減少了芯片的熱溫度。永磁直流電動(dòng)機(jī)的其他重要特色是電阻在交界溫度下傳導(dǎo)系數(shù)和及其包裝和散熱器。目前機(jī)器人中主要用到兩大類晶體管:雙極晶體管(雙極型)和場(chǎng)效應(yīng)晶體管(場(chǎng)效應(yīng)),在雙極晶體管中,基本電路中產(chǎn)生的電流能夠調(diào)節(jié)發(fā)射端和接受端之間的電流。在場(chǎng)效應(yīng)器件中存在著一個(gè)電場(chǎng),此電場(chǎng)可以調(diào)節(jié)電源和阻抗之間的電流。 傳感器:根據(jù)不同的任務(wù),機(jī)器人的不同反應(yīng)需要不同類型的傳感器。在大多數(shù)系統(tǒng)中,通過(guò)電路和編程來(lái)定時(shí)時(shí)間,在生產(chǎn)實(shí)踐中,機(jī)器人必須有靈敏的感知硬件和軟件。不管是傳感器的硬件還是軟件,傳感器和感知,都可以被看作與外部事件或外面的世界之間的交流。傳感器技術(shù)在一定程度上也影響著社會(huì)上其它技術(shù)的發(fā)展,同時(shí)人們將傳感器和轉(zhuǎn)換器交叉利用。轉(zhuǎn)換器通常是一個(gè)裝置或傳感器的一個(gè)元素,它可以將能源轉(zhuǎn)換為另一種形式的能量,傳感器接收能源并傳送一個(gè)信號(hào)到顯示器或計(jì)算機(jī)。傳感器使用轉(zhuǎn)換器將輸入信號(hào)(聲音、光、壓力、溫度等)轉(zhuǎn)換為模擬或數(shù)字形式,這些數(shù)字和模擬量才可以被機(jī)器人利用。微系統(tǒng):微控制器(單片機(jī))是機(jī)器人內(nèi)部的智能電子器件,他的功能類似于微處理器(電腦的中央處理單元,或 CPU)。雖然微系統(tǒng)的速度較慢,能夠處理的內(nèi)存少比中央處理器的少,但它主要是對(duì)實(shí)際任務(wù)的控制。微系統(tǒng)和中央處理器的主要區(qū)別是,中央處理器有眾多的外部元件需要來(lái)操作。而微系統(tǒng)不需要去操作外界的零部件,它通常只需要一個(gè)外部晶體或振蕩器。微控制器通常包括四個(gè)基本方面:速度、規(guī)模、存儲(chǔ)器及其他。速度是指定時(shí)時(shí)鐘周期,而且通常是以百萬(wàn)赫茲每秒來(lái)計(jì)算。時(shí)鐘周期的不同影響了微控制器的速度。規(guī)模的大小表示微控制器每步能夠處理多少信息比特流。微控制器的程序可以一步擴(kuò)大自然數(shù)組的信息。微控制器進(jìn)來(lái)通常有 4 位、8 位、16 位和 32 位,其中最常見(jiàn)的是 8位的微控制器。 微控制器分別以千字節(jié)(kb) 和單字節(jié)來(lái)計(jì)算大部分光盤和 RAM的存儲(chǔ)量。很多單片機(jī)采用哈佛結(jié)構(gòu),在該結(jié)構(gòu)內(nèi)是存放信息的內(nèi)存(通常是內(nèi)部或外部的 SRAM)。這種方法能使處理器更有效率處理單獨(dú)的記憶信息。第四方面微系統(tǒng)的“其他”的包括這樣的功能,如專用設(shè)備的投入,往往(但并非總是)有一個(gè)小型 LED 或 LCD 顯示器輸出。例如單片機(jī)也需投入設(shè)備和以不同成份的裝置控制它發(fā)出的信號(hào),同時(shí)單片機(jī)程序指針還跟蹤正在執(zhí)行的任務(wù),看程序是否能正常運(yùn)行下去。早在處理放射性材料的原子實(shí)驗(yàn)室里,工業(yè)機(jī)器人被稱為主/從機(jī)械臂。他們通過(guò)機(jī)械聯(lián)動(dòng)和鋼電纜聯(lián)系起來(lái),現(xiàn)在遙控機(jī)器人手臂可以通過(guò)按鈕、開(kāi)關(guān)或手柄來(lái)進(jìn)行移動(dòng)。目前機(jī)器人擁有先進(jìn)的感覺(jué)系統(tǒng),就像人類擁有的大腦一樣能夠處理進(jìn)信息,完成不同的工作。它們的“大腦“實(shí)際上是一種計(jì)算機(jī)人工智能(AI),人工智能使機(jī)器人感覺(jué)內(nèi)外部狀況的變化,并根據(jù)所獲得的信息決定采取相應(yīng)的行動(dòng)。 機(jī)器人(人造的)手臂的能夠模仿人手的組合運(yùn)動(dòng),完成各種不同性質(zhì)的工作都是有可能的。機(jī)器人的手臂可以作出如下五種運(yùn)動(dòng):整個(gè)手臂可以轉(zhuǎn)動(dòng)的底座、手臂可以提高或降低、手部(抓取機(jī)構(gòu))能夠延長(zhǎng)或撤回、手臂可以旋轉(zhuǎn)、手掌的手指能夠伸展和閉合 。機(jī)械人手臂可以看作是一個(gè)整體系統(tǒng)。所有用于自動(dòng)分析的儀器都被設(shè)計(jì)在手臂能夠達(dá)到的范圍內(nèi),此外,這些儀器由電腦控制。在這種情況下需要的儀器主要包括:離心機(jī)(常用于分析血液樣本) 、分析儀(如分光光度計(jì)) 、存放樣本的儀器、平衡裝置、一個(gè)空調(diào)機(jī)組(可能為攪拌器或烘箱)、配藥和提取藥品的工具、稀釋化學(xué)品的工具。 計(jì)算機(jī)描述機(jī)器手臂的運(yùn)動(dòng)需要很多具體的步驟,甚至是一個(gè)很簡(jiǎn)單的任務(wù)也需要數(shù)以千計(jì)的操作和指令。對(duì)于用戶來(lái)說(shuō),完成這項(xiàng)規(guī)劃任務(wù)將需要很長(zhǎng)的時(shí)間,它需要用戶準(zhǔn)確地預(yù)測(cè)精確座標(biāo)軸各運(yùn)動(dòng)或每一個(gè)理想的位置。反之,機(jī)器人一般都裝有一系列簡(jiǎn)單任務(wù)的程序,這些程序被稱做預(yù)備程序。每個(gè)預(yù)備程序都是用來(lái)描述機(jī)器手臂的一個(gè)動(dòng)作。用戶根據(jù)一定的資料來(lái)安裝手臂和其他零部件。當(dāng)用戶對(duì)機(jī)器手臂的動(dòng)作感到滿意時(shí),這些資料就被計(jì)算機(jī)搜集并存入記憶。按照這種方法一個(gè)很復(fù)雜的動(dòng)作就產(chǎn)生了。計(jì)算機(jī)會(huì)根據(jù)不同儀器的指令產(chǎn)生化學(xué)分析和加工的程序,這些程序是和復(fù)雜的動(dòng)作一一對(duì)應(yīng)的。通過(guò)計(jì)算機(jī)里的程序可對(duì)執(zhí)行精確動(dòng)作的機(jī)器手臂作進(jìn)行例行實(shí)驗(yàn)。我門要根據(jù)所要完成的任務(wù)來(lái)編寫程序,同時(shí)將執(zhí)行任務(wù)的儀器考慮進(jìn)去。當(dāng)電腦不能夠從輸出裝置獲得運(yùn)行、狀態(tài)的信息時(shí),未完成的工作被認(rèn)為是特殊儀器的控制導(dǎo)致的,這樣程序就需要合適的時(shí)間延遲。在制造業(yè)領(lǐng)域,機(jī)器人的開(kāi)發(fā)重點(diǎn)是制造工藝的工程機(jī)械臂。在航天業(yè)業(yè)中,機(jī)器人技術(shù)集中在高度專門化,譬如一種行星探測(cè)車機(jī)器人,它和一臺(tái)高度自動(dòng)化的生產(chǎn)工廠不同,是在月球的黑暗面探進(jìn)行測(cè)作業(yè)。在沒(méi)有無(wú)線電通信的情況下,它們會(huì)遇到意想不到的情況,它必須具備一定的傳感系統(tǒng),能夠?qū)⒏兄男畔⑦M(jìn)行分析,進(jìn)而改變探測(cè)車的行動(dòng)來(lái)適應(yīng)環(huán)境的變化。此外,它還需要有人工智能系統(tǒng)對(duì)可能遇到的未知情況進(jìn)行感知和適應(yīng)。機(jī)器人的應(yīng)用雖然提高了生產(chǎn)效率,但它們并不是特別快。目前,一個(gè)機(jī)器人的生產(chǎn)效率和一個(gè)操作者的生產(chǎn)效率不相上下,機(jī)器人的每個(gè)重大動(dòng)作大約需要一秒時(shí)間。機(jī)器人從傳送帶上拾起一鋼塊到把它放置到車床,需要 10 個(gè)不同的動(dòng)作,這樣就耗時(shí)將近十秒鐘。而一個(gè)操作人員在這段時(shí)間里同樣能完成這項(xiàng)工作。生產(chǎn)率的提高是由于連續(xù)的一致性操作來(lái)實(shí)現(xiàn)的。如果操作人員在一整天的時(shí)間內(nèi)反復(fù)地重復(fù)同一種工作,他的速度就會(huì)逐漸的放慢下來(lái)。機(jī)器人卻能連續(xù)不間斷的進(jìn)行程序的運(yùn)行,在一個(gè)工作日內(nèi)生產(chǎn)出更多零部件。專門的自動(dòng)化機(jī)器也可以達(dá)到機(jī)器人的生產(chǎn)效率。甚至在相同的工作時(shí)間里,專門自動(dòng)化機(jī)器的生產(chǎn)效率是操作人員或機(jī)器人的二倍。但問(wèn)題是,制造出的專門自動(dòng)化機(jī)器只能應(yīng)用在一種工作中,如果工作有了變化,這種機(jī)器就需要很大改進(jìn)或報(bào)廢,甚至不得不重新制造,然而機(jī)器人只需改變一下程序當(dāng)天就可以開(kāi)始新的工作了。但是專門的自動(dòng)化機(jī)器也有它存在的可能性,如果知道一項(xiàng)工作在今后很多年內(nèi)不會(huì)改變,制造專門的自動(dòng)化機(jī)器是一個(gè)不錯(cuò)的選擇。工廠里其他的工作,普通的機(jī)器也能完成。但像噴漆這樣的工作,利用機(jī)器人來(lái)完成就再好不過(guò)了,因?yàn)閲娖崾且豁?xiàng)危險(xiǎn)的工作,油漆揮發(fā)出來(lái)的氣體帶有毒性和可爆炸性,同時(shí)機(jī)器人能在密封的環(huán)境下進(jìn)行噴漆。針對(duì)內(nèi)部形狀不同的機(jī)器,機(jī)器人根據(jù)內(nèi)部程序的不同來(lái)完成噴漆工作。當(dāng)機(jī)器人在有毒的環(huán)境下工作,人們可以不去擔(dān)心噴漆室的毒氣會(huì)對(duì)它造成傷害。連續(xù)的目標(biāo)控制系統(tǒng)具有高度的靈活性和控制功能。今天的工業(yè)機(jī)器人一旦被編入了程序,他就有了自動(dòng)控制的功能。由于受到傳感器發(fā)展的限制,機(jī)器人能夠?qū)ν獠凯h(huán)境變化作出的靈活性也受到了限制,同時(shí)它也是計(jì)算機(jī)視覺(jué)研究的動(dòng)力??刂葡到y(tǒng)是非常靈活,但它仍然需要依靠工作人員來(lái)進(jìn)行控制。通過(guò)增強(qiáng)傳感器的反饋能力,先進(jìn)的機(jī)器人正在向更高的工作靈活性發(fā)展。人工智能、傳感器集成化技術(shù)、計(jì)算機(jī)視覺(jué)技術(shù)以及無(wú)線 VAD/CAM 的程序化將會(huì)使控制系統(tǒng)變的更具有經(jīng)濟(jì)性和普遍性。作為人工控制的增強(qiáng)部分,控制系統(tǒng)正在向自主運(yùn)作的方向發(fā)展。控制管理和人機(jī)交流方法的研究減輕了人們的工作負(fù)擔(dān),計(jì)算機(jī)的數(shù)據(jù)庫(kù)管理提高了操作效率。 人類的研究活動(dòng)對(duì)機(jī)器人和控制系統(tǒng)來(lái)說(shuō)非常的普通,它的目標(biāo)是降低成本和擴(kuò)大應(yīng)用的領(lǐng)域,這些需要先進(jìn)的編程語(yǔ)言和提高人機(jī)交流方法。從軍事科技、空間探索到醫(yī)療產(chǎn)業(yè)和商業(yè),人類已經(jīng)充分意識(shí)到了利用機(jī)器人的優(yōu)勢(shì)。更重要的一點(diǎn)他們逐漸成為我們?nèi)粘I詈徒?jīng)驗(yàn)積累中不可或卻的一部分。機(jī)器人憑借以下優(yōu)勢(shì)將人類從危險(xiǎn)和惡劣的環(huán)境中解放出來(lái):一、安全性:機(jī)器人技術(shù)已發(fā)展到能處理核安全和放射性化學(xué)品等方面,例如核武器、發(fā)電廠、環(huán)境治理、生產(chǎn)某些藥物。二、服從性:機(jī)器人執(zhí)行的很多任務(wù)都是繁重和人類感到厭煩卻又不得不做的,像焊接和清潔衛(wèi)生的工作。三、重復(fù)性和高精度:機(jī)器人已經(jīng)被廣泛用在裝配線、太空探索等需要高精度的工作中。附件 2:外文原文The RobotsRobot can be defined as a programmable, self-controlled device consisting of electronic, electrical, or mechanical units. More generally, it is a machine that functions in place of a living agent. Robots are especially desirable for certain work functions because, unlike humans, they never get tired; they can endure physical conditions that are uncomfortable or even dangerous; they can operate in airless conditions; they do not get bored by repetition; and they cannot be distracted from the task at hand. Characteristics that make robots different from regular machinery are that robots usually function by themselves, are sensitive to their environment, adapt to variations in the environment or to errors in prior performance, are task oriented and often have the ability to try different methods to accomplish a task. .Common industrial robots are generally heavy rigid devices limited to manufacturing. They operate in precisely structured environments and perform single highly repetitive tasks under preprogrammed control. There were an estimated 720,000 industrial robots in 1998. Teleported robots are used in semi-structured environments such as undersea and nuclear facilities. They perform non-repetitive tasks and have limited real-time control..The concept of robots is a very old one yet the actual word robot was invented in the 20th century from the Czechoslovakian word robot or robotics meaning slave, servant, or forced labor. Robots don't have to look or act like humans but they do need to be flexible so they can perform different tasks. The word "robot" originates from the Czech word for forced labor, or serf. It was introduced by playwright Karel Capek, whose fictional robotic inventions were much like Dr. Frankenstein's monster -- creatures created by chemical and biological, rather than mechanical, methods. But the current mechanical robots of popular culture are not much different from these fictional biological creations.The field of robotics has created a large class of robots with basic physical and navigational competencies. At the same time, society has begun to move towards incorporating robots into everyday life, from entertainment to health care. Moreover, robots could free a large number of people from hazardous situations, essentially allowing them to be used as replacements for human beings. Many of the applications being pursued by AI robotics researchers are already fulfilling that potential. In addition, robots can be used for more commonplace tasks such as janitorial work. Whereas robots were initially developed for dirty, dull, and dangerous applications, they are now being considered as personal assistants. Regardless of application, robots will require more rather than less intelligence, and will thereby have a significant impact on our society in the future as technology expands to new horizons. Basically a robots consists of: A mechanical device, such as a wheeled platform, arm, or other construction, capable of interacting with its environment; Sensors on or around the device that are able to sense the environment and give useful feedback to the device; Systems that process sensory input in the context of the device's current situation and instruct the device to perform actions in response to the situation Mechanical platforms -- the hardware base: A robot consists of two main parts: the robot body and some form of artificial intelligence (AI) system. Many different body parts can be called a robot. Articulated arms are used in welding and painting; gantry and conveyor systems move parts in factories; and giant robotic machines move earth deep inside mines. One of the most interesting aspects of robots in general is their behavior, which requires a form of intelligence. The simplest behavior of a robot is locomotion. Typically, wheels are used as the underlying mechanism to make a robot move from one point to the next. And some force such as electricity is required to make the wheels turn under command. Motors: A variety of electric motors provide power to robots, allowing them to move material, parts, tools, or specialized devices with various programmed motions. The efficiency rating of a motor describes how much of the electricity consumed is converted to mechanical energy. Let's take a look at some of the mechanical devices that are currently being used in modern robotics technology. Driving mechanisms: Gears and chains are mechanical platforms that provide a strong and accurate way to transmit rotary motion from one place to another, possibly changing it along the way. The speed change between two gears depends upon the number of teeth on each gear. When a powered gear goes through a full rotation, it pulls the chain by the number of teeth on that gear. Power supplies: Power supplies are generally provided by two types of battery. Primary batteries are used once and then discarded; secondary batteries operate from a (mostly) reversible chemical reaction and can be recharged several times. Primary batteries have higher density and a lower self-discharge rate. Secondary (rechargeable) batteries have less energy than primary batteries, but can be recharged up to a thousand times depending on their chemistry and environment. Typically the first use of a rechargeable battery gives 4 hours of continuous operation in an application or robot. There are literally hundreds of types and styles of batteries available for use in robots. Batteries are categorized by their chemistry and size, and rated by their voltage and capacity. The voltage of a battery is determined by the chemistry of the cell, and the capacity by both the chemistry and size. See Table 1 for battery sizes. The robot platform runs off of two separate battery packs, which share only a ground. This way, the motor may dirty up one power source while the electronics can run off of the other. The electronics and the motors can also operate from different voltages. There are two major hardware platforms in a robot. The mechanical platform of unregulated voltages, power and back-EMF spikes, and the electronic platform of clean power and 5-volt signals. These two platforms need to be bridged in order for digital logic to control mechanical systems. The classic component for this is a bridge relay. A control signal generates a magnetic field in the relay's coil that physically closes a switch. MOSFETs, for example, are highly efficient silicon switches, available in many sizes like the transistor that can operate as a solid state relay to control the mechanical systems. On the other hand, larger sized robots may require a PMDC motor in which the value of the MOSFET's "on" resistance Rds (on) results in great increases in the heat dissipation of the chip, thereby significantly reducing the chip's heat temperature. Junction temperatures within the MOSFET and the coefficients of conduction of the MOSFET package and heat sink are other important characteristics of PMDC motors. There are two broad families of transistor: bipolar junction transistors (BJT) and field-effect transistors (FET). In BJT devices, a small current flow at the base moderates a much larger current between the emitter and collector. In FET devices, the presence of an electrical field at the gate moderates the flow between the source and drain. Sensors: Robots react according to a basic temporal measurement, requiring different kinds of sensors. In most systems a sense of time is built-in through the circuits and programming. For this to be productive in practice, a robot has to have perceptual hardware and software, which updates quickly. Regardless of sensor hardware or software, sensing and sensors can be thought of as interacting with external events (in other words, the outside world). The sensor measures some attribute of the world. The term transducer is often used interchangeably with sensor. A transducer is the mechanism, or element, of the sensor that transforms the energy associated with what is being measured into another form of energy. A sensor receives energy and transmits a signal to a display or computer. Sensors use transducers to change the input signal (sound, light, pressure, temperature, etc.) into an analog or digital form capable of being used by a robot. On the other hand, larger sized robots may require a PMDC motor in which the value of the MOSFET's "on" resistance Microcontroller systems: Microcontrollers (MCUs) are intelligent electronic devices used inside robots. They deliver functions similar to those performed by a microprocessor (central processing unit, or CPU) inside a personal computer. MCUs are slower and can address less memory than CPUs, but are designed for real-world control problems. One of the major differences between CPUs and MCUs is the number of external components needed to operate them. MCUs can often run with zero external parts, and typically need only an external crystal or oscillator. There are four basic aspects of a microcontroller: speed, size, memory, and other. Speed is designated in clock cycles, and is usually measured in millions of cycles per second (Megahertz, MHz). The use of the cycles varies in different MCUs, affecting the usable speed of the processor. Size specifies the number of bits of information the MCU can process in one step -- the size of its natural cluster of information. MCUs come in 4-, 8-, 16-, and 32-bits, with 8-bit MCUs being the most common size. MCUs count most of their ROM in thousands of bytes (KB) and RAM in single bytes. Many MCUs use the Harvard architecture, in which the program is kept in one section of memory (usually the internal or external SRAM). This in turn allows the processor to access the separate memories more efficiently. The fourth aspect of microcontrollers, referred to as "other", includes features such as a dedicated input device that often (but not always) has a small LED or LCD display for output. A microcontroller also takes input from the device and controls it by sending signals to different components in the device. Also the program counter keeps track of which command is to be executed by the microcontroller. Early industrial robots handled radioactive material in atomic labs and were called master/slave manipulators. They were connected together with mechanical linkages and steel cables. Remote arm manipulators can now be moved by push buttons, switches or joysticks. Current robots have advanced sensory systems that process information and appear to function as if they have brains. Their "brain" is actually a form of computerized artificial intelligence (AI). AI allows a robot to perceive conditions and decide upon a course of action based on those conditions. Robotic (articulated) arms emulate the motions of a human arm/hand combination. variety of arrangements for accomplishing this are possible .Five independent motions are summarized as follows:(1)The entire arm can rotate on the base plate.(2)The arm can be raised or lowered(3)The hand (grippers) can be extended or withdrawn.(4)The hand can rotate.(5)The fingers of the hand can open and close (yaw).Consider this robotic arm integrated into a system. All of the instrumentationnecessary for the automated analysis is located within the operational range of the robotic arm. In addition the instruments are under computer control. Instruments in such cases may include:a centrifuge (e. g. for analysis of blood samples ); an analytic instrument (e. g. a spectrophotometer or chromatograph); a rack to hold the samples ;a balance ;a conditioning unit (possibly a stirrer or temperature oven);an instrument for dispensing , extracting and/or diluting chemicals.A computer description of the motion of the robotic arm requires many detailed steps, even for simple tasks. This can include literally thousands of operations or instructions. for the user to complete such a programming task prior to successful operation of the program would take a prohibitively long time; it requires the user to predict accurately the precise coordinates of all axes of motion or each desired position .instead, robotic arms usually come with a series of programs that greatly simplify the task . These programs are often called training programs .a training program tasks the position of each member of the robotic arm . users position the arm and its members manually, using either a manipulanda or reserved keystrokes in combination with numerical information. When the user is satisfied with the successive motion that the robotic arm is to make ,the data—as tracked by the computer –are stored in the computer’s memory .in this way a complex sequence of motions can be generated. These motions coupled with commands to the individual instruments produce an automated procedure for chemical analysis or processing.A program within the computer can be used to define precisely the steps taken by the robotic arm to carry out a routine test. This program must also take into consideration the tasks to be carried out by each instrument. When the computer does not obtain ongoing, continuous, status information from an instrument, the resultant Arrangement is referred to as open-loop control of the particular instrument. then the program must include appropriate time delays.In the manufacturing field, robot development has focused on engineering robotic arms that perform manufacturing processes. In the space industry, robotics focuses on highly specialized, one-of-kind planetary rovers. Unlike a highly automated manufacturing plant, a planetary rover operating on the dark side of the moon -- without radio communication -- might run into unexpected situations. At a minimum, a planetary rover must have some source of sensory input, some way of interpreting that input, and a way of modifying its actions to respond to a changing world. Furthermore, the need to sense and adapt to a partially unknown environment requires intelligence (in other words, artificial intelligence).Although robots increase productivity in a manufacturing plant,they are not exceptionally fast. At present, robots normally at or near the speed of a human operator.every major move of a robot normally takes approximately one second.for a robot to pick up a piece of steel from a conveyor and load it into a lathe may require ten different moves taking as much as ten seconds. A human operator can do the same amount of time.the increase in productivity is a result of thr consistency of operation.as the human operator repeats the s
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