抽油機機械系統(tǒng)設(shè)計(常規(guī)型)
抽油機機械系統(tǒng)設(shè)計(常規(guī)型),抽油機機械系統(tǒng)設(shè)計(常規(guī)型),抽油機,機械,系統(tǒng),設(shè)計,常規(guī)
1.課程設(shè)計的原始數(shù)據(jù) 假設(shè)電動機做勻速轉(zhuǎn)動,抽油機的運動周期為T,抽油桿的上沖程時間5T/9,下沖程時間4T/9。沖程S=1.4m,沖次n11次/min,上沖程由于舉升原油,作用于懸點的載荷等于原油的重量加上抽油桿和柱塞自身的重量為40kN,下沖程原油已釋放,作用于懸點的載荷就等于抽油桿和柱塞自身的重量為15kN。 2.課程設(shè)計(論文)的內(nèi)容和要求(包括技術(shù)要求、圖表要求以及工作要求): 1.調(diào)研,收集資料,查閱文獻十篇以上(其中外文資料不少于一篇)。 2.寫開題報告:包括工作任務(wù)分析、調(diào)研報告或文獻綜述、方案擬訂與分析以及實施計劃等,開題報告須單獨裝訂。 3. 專機要求:外形美觀,尺寸緊湊。 4.繪制裝配圖與零件圖以及三維模擬。 5.撰寫論文。 6.翻譯外文資料。 7.整理,準備答辯。 : 目錄:1 設(shè)計任務(wù)*(1)2 設(shè)計內(nèi)容*(2)3 方案分析*(2)4 設(shè)計目標*(3)5 設(shè)計分析*(3)6 電機選擇*(7)7 V帶傳動設(shè)計*(10)8 齒輪傳動設(shè)計*(11)9 軸的結(jié)構(gòu)設(shè)計*(19)10軸承壽命校核*(21)11心得與總結(jié)*(25)12附錄*(26)設(shè)計任務(wù): 抽油機機械系統(tǒng)設(shè)計 抽油機是將原油從井下舉升到地面的主要采油設(shè)備之一。常用的有桿抽油設(shè)備由三部分組成:一是地面驅(qū)動設(shè)備即抽油機;二是井下的抽油泵,它懸掛在油井油管的下端;三是抽油桿,它將地面設(shè)備的運動和動力傳遞給井下抽油泵。抽油機由電動機驅(qū)動,經(jīng)減速傳動系統(tǒng)和執(zhí)行系統(tǒng)(將轉(zhuǎn)動變換為往復(fù)移動)帶動抽油桿及抽油泵柱塞作上下往復(fù)移動,從而實現(xiàn)將原油從井下舉升到地面的目的。 懸點執(zhí)行系統(tǒng)與抽油桿的聯(lián)結(jié)點懸點載荷P(kN)抽油機工作過程中作用于懸點的載荷抽油桿沖程S(m)抽油桿上下往復(fù)運動的最大位移沖次n(次/min)單位時間內(nèi)柱塞往復(fù)運動的次數(shù)懸點載荷P的靜力示功圖在柱塞上沖程過程中,由于舉升原油,作用于懸點的載荷為P1,它等于原油的重量加上抽油桿和柱塞自身的重量;在柱塞下沖程過程中,原油已釋放,此時作用于懸點的載荷為P2,它就等于抽油桿和柱塞自身的重量。假設(shè)電動機作勻速轉(zhuǎn)動,抽油桿(或執(zhí)行系統(tǒng))的運動周期為T。油井工況為:上沖程時間下沖程時間沖程S(M)沖次N(次/MIN)懸點載荷P(N)8T/157T/151.314設(shè)計內(nèi)容:1. 根據(jù)任務(wù)要求,進行抽油機機械系統(tǒng)總體方案設(shè)計,確定減速傳動系統(tǒng)、執(zhí)行系統(tǒng)的組成,繪制系統(tǒng)方案示意圖。2. 根據(jù)設(shè)計參數(shù)和設(shè)計要求,采用優(yōu)化算法進行執(zhí)行系統(tǒng)(執(zhí)行機構(gòu))的運動尺寸設(shè)計,優(yōu)化目標為抽油桿上沖程懸點加速度為最小,并應(yīng)使執(zhí)行系統(tǒng)具有較好的傳力性能。3. 建立執(zhí)行系統(tǒng)輸入、輸出(懸點)之間的位移、速度和加速度關(guān)系,并編程進行數(shù)值計算,繪制一個周期內(nèi)懸點位移、速度和加速度線圖(取抽油桿最低位置作為機構(gòu)零位)。4. 選擇電動機型號,分配減速傳動系統(tǒng)中各級傳動的傳動比,并進行傳動機構(gòu)的工作能力設(shè)計計算。5. 對抽油機機械系統(tǒng)進行結(jié)構(gòu)設(shè)計,繪制裝配圖及關(guān)鍵零件工作圖。6. 編寫機械設(shè)計課程設(shè)計報告。方案分析:1.根據(jù)任務(wù)要求,進行抽油機機械系統(tǒng)總體方案設(shè)計,確定減速傳動系統(tǒng)、執(zhí)行系統(tǒng)的組成。該系統(tǒng)的功率大,且總傳動比大。減速傳動系統(tǒng)方案很多,以齒輪減速器減速最為常見且設(shè)計簡單,有時可以綜合帶傳動的平穩(wěn)傳動特點來設(shè)計減速系統(tǒng)。在這里我選用帶傳動加上齒輪二級減速。執(zhí)行系統(tǒng)方案設(shè)計:輸入連續(xù)單向轉(zhuǎn)動;輸出往復(fù)移動輸入、輸出周期相同,輸入轉(zhuǎn)1圈的時間有急回。常見可行執(zhí)行方案有很多種,我選用“四連桿(常規(guī))式抽油機”機構(gòu)。設(shè)計目標: 以上沖程懸點加速度為最小進行優(yōu)化,即搖桿CD順時針方向擺動過程中的3max最小,由此確定a、b、c、d。設(shè)計分析:執(zhí)行系統(tǒng)設(shè)計分析: 設(shè)計要求抽油桿上沖程時間為8T/15,下沖程時間為7T/15,則可推得上沖程曲柄轉(zhuǎn)角為192,下沖程曲柄轉(zhuǎn)角為168。找出曲柄搖桿機構(gòu)搖桿的兩個極限位置。CD順時針擺動C1C2,上 沖 程 ( 正 行 程 ) , P1 ,=192,慢行程,B1 B2;CD逆時針擺動C2C1,下 沖 程 ( 反 行 程 ) , P2 ,=168,快行程,B2 B1。 = 。曲柄轉(zhuǎn)向應(yīng)為逆時針,型曲柄搖桿機構(gòu) a2 + d 2 b2 + c2設(shè)計約束:(1) 極位夾角(2)行程要求通常取e/c=1.35 S = e =1.35c(3)最小傳動角要求(4) 其他約束整轉(zhuǎn)副由極位夾角保證。各桿長0。其中極位夾角約束和行程約束為等式約束,其他為不等式約束。型曲柄搖桿機構(gòu)的設(shè)計:若以為設(shè)計變量,因S=1.35c ,則當(dāng)取定時,可得c。根據(jù)c、作圖,根據(jù)作圓,其半徑為r。各式表明四桿長度均為和的函數(shù)取和為設(shè)計變量根據(jù)工程需要:優(yōu)化計算:.在限定范圍內(nèi)取、,計算c、a、d、b,得曲柄搖桿機構(gòu)各構(gòu)件尺寸;.判斷最小傳動角;.取抽油桿最低位置作為機構(gòu)零位:曲柄轉(zhuǎn)角=0,懸點位移S=0,求上沖程曲柄轉(zhuǎn)過某一角度時搖桿擺角、角速度和角加速度3(可按步長0.5循環(huán)計算);.找出上沖程過程中的最大值3max。對于II型四桿機構(gòu),已知桿長為a,b,c,d,原動件a的轉(zhuǎn)角及等角速度為(,n 為執(zhí)行機構(gòu)的輸入速度). 從動件位置分析(如圖所示),為AD桿的角度機構(gòu)的封閉矢量方程式為:(1.1)歐拉公式展開令方程實虛部相等(1.2)消去得,(1.3)其中又因為代入(1.3)得關(guān)于的一元二次方程式,解得(1.4)B構(gòu)件角位移可求得(1.5)速度分析對機構(gòu)的矢量方程式求導(dǎo)數(shù)得(1.6)將上式兩邊分別乘以或得或(1.7)(1.8)加速度分析將(1.6)式對時間求導(dǎo)得(1.9)對上式兩邊同乘或得或應(yīng)用網(wǎng)格法編程計算可得(具體程序見附錄)a=0.4537圓整為0.454;b=1.2297圓整為1.230c=1.2261圓整為1.226;d=1.8539圓整為1.854則e=1.3/0.7854=1.655電機選擇:Matlab分析,懸點最大速度在上沖程且rad/s,則m/s。根據(jù)工況初采用展開式二級圓柱齒輪減速,聯(lián)合V型帶傳動減速,選用三相籠型異步電機 ,封閉式結(jié)構(gòu),電壓380VY型由電機至抽油桿的總傳動效率為:其中,分別為帶傳動、軸承、齒輪傳動、聯(lián)軸器和四連桿執(zhí)行機構(gòu)的傳動效率。取0.94,取0.98,取0.97,取0.99,取0.90。預(yù)選滾子軸承,8級斜齒圓柱齒輪,考慮到載荷較大且有一定沖擊,兩軸線同軸度對系統(tǒng)有一定影響,可考慮用齒輪聯(lián)軸器。則則電動機所需工作功率根據(jù)手冊推薦的傳動比合理范圍,取V帶傳動的傳動比為,二級圓柱齒輪減速器傳動比,則總傳動比的合理范圍為,故電機轉(zhuǎn)速可選范圍為 r/min符合這一范圍的同步轉(zhuǎn)速有750,1000,1500 r/min考慮速度太小的電機價格、體積、重量等因素,不宜選取電機型號功率kW轉(zhuǎn)速r/min380V時電流A效率%功率因素額定轉(zhuǎn)矩額定電流最大額矩dBdB/A凈重KgY250M-655983104.2910.871.86.52.087465Y225M-4551476103.691.50.881.87.02.089380比較后綜合考慮,選定電機型號為Y250M-6,其外形及安半裝尺寸如下:機座號ABCDEFxGDGH250M4063491687514020x1267.5250KAAABACADBBHAHDL2410051055041045530600825確定傳動裝置的總傳動比和分配傳動比分配傳動比,初選V帶,以致其外廓尺寸不致過大,則減速器傳動比為則展開式齒輪減速器,由手冊展開式曲線查得高速級,則計算傳動裝置的運動和動力參數(shù)將傳動裝置各軸由高速至低速依次定為I、II、III軸以及為相鄰兩軸間的傳動比為相鄰兩軸間的傳動效率為各軸的輸入功率(kW)為各軸的輸入轉(zhuǎn)矩(kW)為各軸的轉(zhuǎn)速(r/min)則各軸轉(zhuǎn)速:I軸II軸III軸曲柄轉(zhuǎn)軸各軸輸入功率:I軸II軸III軸曲柄轉(zhuǎn)軸各軸輸出功率分別為輸入功率乘軸承效率0.98,則各軸輸入轉(zhuǎn)矩:電機輸出轉(zhuǎn)矩I軸II軸III軸曲柄轉(zhuǎn)軸IIII軸的輸出轉(zhuǎn)矩則分別為各軸輸入轉(zhuǎn)轉(zhuǎn)矩乘軸承效率0.98V帶傳動設(shè)計: 初選普通V帶查表,由于載荷變動較大取1.3,P51kW故 選取為D型帶,小帶輪355400mm。查表初選375mm大輪準直徑,在允許范圍內(nèi)取 驗算帶速v 在1020之間,故能充分發(fā)揮V帶的傳動能力。 確定中心距a和帶的基準長度初定中心距帶長初選 查表取 實際中心距實際中心距調(diào)節(jié)范圍推薦值為: 驗算小帶輪包角包角合適 確定帶的根數(shù)因 傳動比 i=2.8,由表線性插值得 則 取z=4 根 確定初拉力F。單根普通V帶的初拉力 D帶q=0.6kg/m 計算帶輪軸所受壓力 帶輪結(jié)構(gòu)設(shè)計(如下)小帶輪大帶輪齒輪傳動設(shè)計:A高速級設(shè)計輸入功率P=47.94kW,小齒輪轉(zhuǎn)速,傳動比。1. 選取齒輪的材料、熱處理及精度設(shè)工作壽命10年(每年工作300天)(1)齒輪材料及熱處理大小齒輪材料選用20CrMnTi。齒面滲碳淬火,齒面硬度為HRC,有效硬化層深0.50.9mm。有圖查得,齒面最終成型工藝為磨齒。(2)齒輪精度級初步設(shè)計齒輪傳動的主要尺寸因所選為硬齒面?zhèn)鲃?,它具有較強的齒面抗點蝕能力,故先按齒根彎曲疲勞強度設(shè)計,再校核齒面接觸疲勞強度。(1) 計算小齒輪傳遞的轉(zhuǎn)矩(2) 確定齒數(shù)z取,傳動比誤差 允許(3) 初選齒寬系數(shù)按非對稱布置,由表查得=0.6(4) 初選螺旋角 (5) 載荷系數(shù) K使用系數(shù),由表查得動載荷系數(shù),估計齒輪圓周速度v=5m/s,則由圖表查得=1.2; 齒向載荷系數(shù),預(yù)估齒寬 b=40mm,由表查得,初取b/h=6,再查圖得=1.15; 齒間載荷分配系數(shù),由表查得 載荷系數(shù)K (6) 齒形系數(shù)和應(yīng)力修正系數(shù) 當(dāng)量齒數(shù) 查表(7) 重合度系數(shù)端面重合度近似為:則(8) 螺旋角系數(shù)軸向重合度 (9) 許用彎曲應(yīng)力安全系數(shù)由表查得小齒輪應(yīng)力循環(huán)次數(shù)大齒輪應(yīng)力循環(huán)次數(shù)查表得壽命系數(shù) ,實驗齒輪應(yīng)力修正系數(shù) 由圖表預(yù)取尺寸系數(shù) 許用彎曲應(yīng)力 比較取(10)計算模數(shù)按表圓整模數(shù),取(11)初算主要尺寸初算中心距 , 取a=356mm修正螺旋角 分度圓直徑 齒寬 ,取 齒寬系數(shù) (12)驗算載荷系數(shù) K 圓周速度 ,由圖查得按,由表查得,又因b/h=b/(2.25)=59/(2.25*5)=5.3由圖查得,不變又和不變,則K=2.90也不變故無須校核大小齒輪齒根彎曲疲勞強度。3校核齒面接觸疲勞強度(1)確定載荷系數(shù)載荷系數(shù) (2) 確定各系數(shù)材料彈性系數(shù) ,由表查得節(jié)點區(qū)域系數(shù) 重合度系數(shù) 螺旋角系數(shù) (3) 許用接觸應(yīng)力試驗齒輪的齒面疲勞極限 壽命系數(shù) ,由圖查得尺寸系數(shù) ,;安全系數(shù)則許用接觸應(yīng)力取(4) 校核齒面接觸強度 滿足齒面接觸強度4計算幾何尺寸 B低速級設(shè)計輸入功率P=45.57kW,小齒輪轉(zhuǎn)速,傳動比。0 選取齒輪的材料、熱處理及精度設(shè)工作壽命10年(每年工作300天)(1)齒輪材料及熱處理大小齒輪材料選用20CrMnTi。齒面滲碳淬火,齒面硬度為HRC,有效硬化層深0.50.9mm。有圖查得,齒面最終成型工藝為磨齒。(2)齒輪精度級初步設(shè)計齒輪傳動的主要尺寸因所選為硬齒面?zhèn)鲃?,它具有較強的齒面抗點蝕能力,故先按齒根彎曲疲勞強度設(shè)計,再校核齒面接觸疲勞強度。(1) 計算小齒輪傳遞的轉(zhuǎn)矩(2) 確定齒數(shù)z取,傳動比誤差 允許(3) 初選齒寬系數(shù)按非對稱布置,由表查得=0.6(4) 初選螺旋角 (5) 載荷系數(shù) K使用系數(shù),由表查得動載荷系數(shù),估計齒輪圓周速度v=5m/s,則由圖表查得=1.03; 齒向載荷系數(shù),預(yù)估齒寬 b=120mm,由表查得,初取b/h=6,再查圖得=1.16; 齒間載荷分配系數(shù),由表查得 載荷系數(shù)K (6) 齒形系數(shù)和應(yīng)力修正系數(shù) 當(dāng)量齒數(shù) 查表(7) 重合度系數(shù)端面重合度近似為:則(8) 螺旋角系數(shù)軸向重合度 (9) 許用彎曲應(yīng)力安全系數(shù)由表查得小齒輪應(yīng)力循環(huán)次數(shù)大齒輪應(yīng)力循環(huán)次數(shù)查表得壽命系數(shù) ,實驗齒輪應(yīng)力修正系數(shù) 由圖表預(yù)取尺寸系數(shù) 許用彎曲應(yīng)力 比較取(10)計算模數(shù)按表圓整模數(shù),取(11)初算主要尺寸初算中心距 , 取a=476mm修正螺旋角 分度圓直徑 齒寬 ,取 齒寬系數(shù) (12)驗算載荷系數(shù) K 圓周速度 ,由圖查得按,由表查得,又因b/h=b/(2.25)=115/(2.25*6)=8.5由圖查得,不變又和不變,則K=2.51也不變故無須校核大小齒輪齒根彎曲疲勞強度。3校核齒面接觸疲勞強度(1)確定載荷系數(shù)載荷系數(shù) (2) 確定各系數(shù)材料彈性系數(shù) ,由表查得節(jié)點區(qū)域系數(shù) 重合度系數(shù) 螺旋角系數(shù) (3) 許用接觸應(yīng)力試驗齒輪的齒面疲勞極限 壽命系數(shù) ,由圖查得尺寸系數(shù) ,;安全系數(shù)則許用接觸應(yīng)力取(4) 校核齒面接觸強度 滿足齒面接觸強度4計算幾何尺寸 軸的結(jié)構(gòu)設(shè)計:I軸:1.選擇軸材料 45鋼 調(diào)質(zhì)217255HBS2.初算軸徑 取A=110 得 因軸上要開鍵槽,故將軸徑增加4%5%,取軸徑為60mm。3.擬定軸的布置方案(如圖)選取31314圓錐滾子軸承II軸:1.選擇軸材料 45鋼 調(diào)質(zhì)217255HBS2.初算軸徑 取A=110 得 因鍵槽影響,故將軸徑增加4%5%,取軸徑為107mm。3.擬定軸的布置方案(如圖)選取32222圓錐滾子軸承III軸:1.選擇軸材料 45鋼 調(diào)質(zhì)217255HBS2.初算軸徑 取A=110 得 因鍵槽影響,故將軸徑增加4%5%,取軸徑為150mm。3.擬定軸的布置方案(如圖)選取32032圓錐滾子軸承軸承壽命校核:I軸:由手冊查得30314 ,取(1) 計算附加軸向力 (2)計算軸承所受軸向載荷 I軸右端軸承被“放松” (3) 計算當(dāng)量動載荷左: 查表知 X=0.40 Y=1.7則右: 查表知 X=1 Y=0則(4) 軸承壽命計算 按左軸承計算 所選軸承合格II軸:由手冊查得32222 ,取(1) 計算附加軸向力 (2)計算軸向載荷 II軸右端軸承被“放松” (3) 計算當(dāng)量動載荷左: 查表知 X=1 Y=0則右: 查表知 X=0.4 Y=1.4則(4) 軸承壽命 按右軸承計算 滿足工程要求III軸:由手冊查得32032 ,取(2) 計算附加軸向力 (2)計算軸向載荷 III軸左端軸承被“放松” (3)計算當(dāng)量動載荷左: 查表知 X=1 Y=0則右: 查表知 X=0.4 Y=1.3則(4)軸承壽命 按右軸承計算 滿足工程要求綜上可得,該設(shè)計符合工程要求。 心得與總結(jié) 終于在我的不懈的努力下,課程設(shè)計完成了。從開始直到設(shè)計基本完成,我有許多感想。這是我們比較獨立的在自己的努力下做一個與課程相關(guān)的設(shè)計。首先要多謝老師給我們的這個機會,還要感謝諸多同學(xué)的幫助。我深切的感覺到,在這次設(shè)計中也暴露出我們的許多薄弱環(huán)節(jié),很多學(xué)過的知識不能靈活應(yīng)用,在這次作業(yè)后才漸漸掌握,以前學(xué)過的東西自己并不是都掌握了,很多知識都已很模糊,經(jīng)過這次設(shè)計又回憶起來了。做作業(yè)的期間用到的手工制圖又得到了鞏固,AutoCAD畫圖軟件也在不斷練習(xí)中進一步深入,學(xué)會了如何去應(yīng)用工程手冊,我體會到錢老師的良苦用心。總的說來,我感覺這次課程設(shè)計學(xué)到了很多東西,是很有意義的。附錄1優(yōu)化設(shè)計程序%找出最優(yōu)的四桿桿長clearsyms Q1 Q2 P1; % Q1為,Q2為,P1為曲柄轉(zhuǎn)角P=0:0.5*pi/180:192*pi/180;Qu1=45*pi/180:0.1*pi/180:55*pi/180;xm=inf;for i=1:length(Qu1); Q1=Qu1(i); Qu2=5*pi/180:0.1*pi/180:(pi/2-pi/9-Q1/2-5*pi/180); for j=1:length(Qu2); Q2=Qu2(j); c=1.3/1.35/Q1; a=c*sin(Q1/2)*(sin(Q2+pi/15)-sin(Q2)/sin(pi/15); b=c*sin(Q1/2)*(sin(Q2+pi/15)+sin(Q2)/sin(pi/15); r=c*sin(Q1/2)/sin(pi/15); g=(c*sin(pi/15+Q1/2)/sin(pi/15); d=sqrt(r2+g2-2*r*g*cos(2*Q2+pi/15); m=pi-acos(b2+c2-(a+d)2)/2/b/c); if m40*pi/180; %判斷傳動角條件 x=0; for k=1:length(P); P1=P(k); P4=acos(d2+(a+b)2-c2)/2/d/(a+b); A=d*cos(P4)-a*cos(P1); B=d*sin(P4)-a*sin(P1); D=(A2+B2+c2-b2)/(-2)/c; P3=2*atan(B+sqrt(A2+B2-D2)/(A-D); P2=atan(b-c*sin(P3)/(A-c*cos(P3); w1=2*14*pi/60; w3=w1*a*sin(P1-P2)/c/sin(P2-P3); w2=w1*a*sin(P1-P3)/b/sin(P3-P2); x3=(-b*w22-a*w12*cos(P1-P2)-c*w32*cos(P3-P2)/c/sin(P3-P2); if abs(x3)x; x=abs(x3); %求出該種情況的最大角速度 end; end; if xxm; %找出最優(yōu)方案 xm=x; %最大加速度 n1=Q1; % n2=Q2; % end; end; end;end;%運行結(jié)束后,輸入a,b,c,d表達式即可求解c=1.3/1.35/n1a=c*sin(n1/2)*(sin(n2+pi/15)-sin(n2)/sin(pi/15)b=c*sin(n1/2)*(sin(n2+pi/15)+sin(n2)/sin(pi/15)r=c*sin(n1/2)/sin(pi/15);g=(c*sin(pi/15+n1/2)/sin(pi/15);d=sqrt(r2+g2-2*r*g*cos(2*n2+pi/15)%運行結(jié)果為c=1.2261 a=0.4537 b=1.2297 d=1.85392.繪出位移、速度、加速度圖%建立fun.m文件function PP3=fun(P1) %a=0.4537;b=1.2297;c=1.2261;d=1.8539;e=1.655;P4=acos(d2+(a+b)2-c2)/2/d/(a+b);A=d*cos(P4)-a*cos(P1);B=d*sin(P4)-a*sin(P1);D=(A2+B2+c2-b2)/(-2)/c;P3=2*atan(B+sqrt(A2+B2-D2)/(A-D);PP3=(pi-acos(c2+(c+a)2-d2)/2/c/(c+a)-P3)*e;P2=atan(b-c*sin(P3)/(A-c*cos(P3);w1=2*14*pi/60;w3=w1*a*sin(P1-P2)/c/sin(P2-P3);ww3=-w3*e;w2=w1*a*sin(P1-P3)/b/sin(P3-P2);x3=(-b*w22-a*w12*cos(P1-P2)-c*w32*cos(P3-P2)/c/sin(P3-P2);xx3=-x3*e;%在主程序中運行fplot(fun,0,2*pi)如圖若將“”行替換為function ww3=fun(P1)則運行fplot(fun,0,2*pi)后,若將“”行替換為function xx3=fun(P1)則運行fplot(fun,0,2*pi)后,3.數(shù)值打印程序如下:P1=0:5*pi/180:2*pi;s=P1; %存放位移v=P1; %存放速度x=P1; %存放加速度a=0.4537;b=1.2297;c=1.2261;d=1.8539;e=1.655;for i=1:length(P1);P4=acos(d2+(a+b)2-c2)/2/d/(a+b);A=d*cos(P4)-a*cos(P1(i);B=d*sin(P4)-a*sin(P1(i);D=(A2+B2+c2-b2)/(-2)/c;P3=2*atan(B+sqrt(A2+B2-D2)/(A-D);PP3=(pi-acos(c2+(c+a)2-d2)/2/c/(c+a)-P3)*e;s(i)=PP3;P2=atan(b-c*sin(P3)/(A-c*cos(P3);w1=2*14*pi/60;w3=w1*a*sin(P1(i)-P2)/c/sin(P2-P3);ww3=-w3*e;v(i)=ww3;w2=w1*a*sin(P1(i)-P3)/b/sin(P3-P2);x3=(-b*w22-a*w12*cos(P1(i)-P2)-c*w32*cos(P3-P2)/c/sin(P3-P2);xx3=-x3*e;x(i)=xx3;end;s %輸出位移v x %輸出速度 加速度角度(。)位移m速度m/s加速度m2/s角度(。)位移m速度m/s加速度m2/s0-0.0042-0.02461.82991851.29170.0841-1.01865-0.00090.05551.84251901.2952-0.0177-1.1265100.00900.13591.83371951.2948-0.1211-1.2107150.02550.21551.80242001.2900-0.2245-1.2647200.04850.29371.74842051.2805-0.3261-1.2837250.07760.36941.67232101.2659-0.4239-1.2661300.11250.44181.57622151.2459-0.5160-1.2135350.15260.51021.46292201.2205-0.6007-1.1304400.19720.57391.33612251.1896-0.6764-1.0235450.24560.63261.20032301.1534-0.7424-0.9004500.29710.68601.06002351.1123-0.7980-0.7680550.35070.73390.91992401.0667-0.8434-0.6322600.40570.77630.78402451.0172-0.8787-0.4971650.46140.81360.65592500.9644-0.9046-0.3650700.51720.84570.53842550.9089-0.9218-0.2372750.57240.87300.43352600.8513-0.9308-0.1139800.62670.89560.34232650.7922-0.93260.0053850.67950.91370.26532700.7321-0.92750.1213900.73070.92720.20222750.6717-0.91620.2346950.78000.93620.15232800.6113-0.89910.34621000.82730.94040.11402850.5514-0.87650.45681050.87250.93970.08562900.4925-0.84890.56681100.91550.93390.06462950.4349-0.81630.67671150.95630.92240.04833000.3791-0.77900.78651200.99490.90520.03363050.3255-0.73730.89641251.03140.88180.01713100.2745-0.69111.00591301.06570.8520-0.00443150.2265-0.64061.11461351.09780.8156-0.03423200.1819-0.58601.22161401.12780.7722-0.07543250.1411-0.52751.32591451.15560.7219-0.13023300.1046-0.46501.42611501.18130.6646-0.20053350.0727-0.39891.52061551.20470.6003-0.28693400.0458-0.32941.60721601.22590.5291-0.38903450.0243-0.25671.68391651.24460.4513-0.50493500.0086-0.18141.74831701.26070.3673-0.6313355-0.0009-0.10831.79781751.27410.2776-0.7634360-0.0042-0.02461.8299 1801.28450.1829-0.89494參考書目:機械設(shè)計吳克堅于曉紅錢瑞明主編高等教育出版社機械設(shè)計與制造工藝簡明手冊許毓潮等中國電力出版社實用機械加工工藝手冊陳宏鈞主編機械工業(yè)出版社2.3機械手手臂結(jié)構(gòu)的設(shè)計按照抓取工件的要求,車床上料機械手的手臂有三個自由度,及手臂的伸縮、左右回轉(zhuǎn)和降(或俯仰)運動。手臂的回轉(zhuǎn)和升降運動是通過立柱來實現(xiàn)的,立柱的橫向移動即為手臂的橫移。手臂的各種運動有氣缸來實現(xiàn)。2.3.1機械手手臂設(shè)計要求機器人手臂的作用,是在一定的載荷和一定的速度下,實現(xiàn)在機器人所要求的工作空間內(nèi)的運動。在進行機器人手臂設(shè)計時,要遵循下述原則;1.應(yīng)盡可能使機器人手臂各關(guān)節(jié)軸相互平行;相互垂直的軸應(yīng)盡可能相交于一點,這樣可以使機器人運動學(xué)正逆運算簡化,有利于機器人的控制。2.機器人手臂的結(jié)構(gòu)尺寸應(yīng)滿足機器人工作空間的要求。工作空間的形狀和大小與機器人手臂的長度,手臂關(guān)節(jié)的轉(zhuǎn)動范圍有密切的關(guān)系。但機器人手臂末端工作空間并沒有考慮機器人手腕的空間姿態(tài)要求,如果對機器人手腕的姿態(tài)提出具體的要求,則其手臂末端可實現(xiàn)的空間要小于上述沒有考慮手腕姿態(tài)的工作空間。3.為了提高機器人的運動速度與控制精度,應(yīng)在保證機器人手臂有足夠強度和剛度的條件下,盡可能在結(jié)構(gòu)上、材料上設(shè)法減輕手臂的重量。力求選用高強度的輕質(zhì)材料,通常選用高強度鋁合金制造機器人手臂。目前,在國外,也在研究用碳纖維復(fù)合材料制造機器人手臂。碳纖維復(fù)合材料抗拉強度高,抗振性好,比重小(其比重相當(dāng)于鋼的1/4,相當(dāng)于鋁合金的2/3),但是,其價格昂貴,且在性能穩(wěn)定性及制造復(fù)雜形狀工件的工藝上尚存在問題,故還未能在生產(chǎn)實際中推廣應(yīng)用。目前比較有效的辦法是用有限元法進行機器人手臂結(jié)構(gòu)的優(yōu)化設(shè)計。在保證所需強度與剛度的情況下,減輕機器人手臂的重量。4.機器人各關(guān)節(jié)的軸承間隙要盡可能小,以減小機械間隙所造成的運動誤差。因此,各關(guān)節(jié)都應(yīng)有工作可靠、便于調(diào)整的軸承間隙調(diào)整機構(gòu)。5.機器人的手臂相對其關(guān)節(jié)回轉(zhuǎn)軸應(yīng)盡可能在重量上平衡,這對減小電機負載和提高機器人手臂運動的響應(yīng)速度是非常有利的。在設(shè)計機器人的手臂時,應(yīng)盡可能利用在機器人上安裝的機電元器件與裝置的重量來減小機器人手臂的不平衡重量,必要時還要設(shè)計平衡機構(gòu)來平衡手臂殘余的不平衡重量。6.機器人手臂在結(jié)構(gòu)上要考慮各關(guān)節(jié)的限位開關(guān)和具有一定緩沖能力的機械限位塊,以及驅(qū)動裝置,傳動機構(gòu)及其它元件的安裝。2.3.2設(shè)計具體采用方案機械手的垂直手臂(大臂)升降和水平手臂(小臂)的伸縮運動都為直線運動。直線運動的實現(xiàn)一般是氣動傳動,液壓傳動以及電動機驅(qū)動滾珠絲杠來實現(xiàn)??紤]到搬運工件的重量較大,考慮加工工件的質(zhì)量達30KG,屬中型重量,同時考慮到機械手的動態(tài)性能及運動的穩(wěn)定性,安全性,對手臂的剛度有較高的要求。綜合考慮,兩手臂的驅(qū)動均選擇液壓驅(qū)動方式,通過液壓缸的直接驅(qū)動,液壓缸既是驅(qū)動元件,又是執(zhí)行運動件,不用再設(shè)計另外的執(zhí)行件了;而且液壓缸實現(xiàn)直線運動,控制簡單,易于實現(xiàn)計算機的控制。因為液壓系統(tǒng)能提供很大的驅(qū)動力,因此在驅(qū)動力和結(jié)構(gòu)的強度都是比較容易實現(xiàn)的,關(guān)鍵是機械手運動的穩(wěn)定性和剛度的滿足。因此手臂液壓缸的設(shè)計原則是缸的直徑取得大一點(在整體結(jié)構(gòu)允許的情況下),再進行強度的較核。同時,因為控制和具體工作的要求,機械手的手臂的結(jié)構(gòu)不能太大,若僅僅通過增大液壓缸的缸徑來增大剛度,是不能滿足系統(tǒng)剛度要求的。因此,在設(shè)計時另外增設(shè)了導(dǎo)桿機構(gòu),小臂增設(shè)了兩個導(dǎo)桿,與活塞桿一起構(gòu)成等邊三角形的截面形式,盡量增加其剛度;大臂增設(shè)了四個導(dǎo)桿,成正四邊形布置,為減小質(zhì)量,各個導(dǎo)桿均采用空心結(jié)構(gòu)。通過增設(shè)導(dǎo)桿,能顯著提高機械手的運動剛度和穩(wěn)定性,比較好的解決了結(jié)構(gòu)、穩(wěn)定性的問題。2.4機械手腕部的結(jié)構(gòu)設(shè)計機器人的手臂運動(包括腰座的回轉(zhuǎn)運動),給出了機器人末端執(zhí)行器在其工作空間中的運動位置,而安裝在機器人手臂末端的手腕,則給出了機器人末端執(zhí)行器在其工作空間中的運動姿態(tài)。機器人手腕是機器人操作機的最末端,它與機器人手臂配合運動,實現(xiàn)安裝在手腕上的末端執(zhí)行器的空間運動軌跡與運動姿態(tài),完成所需要的作業(yè)動作。2.4.1機器人手腕結(jié)構(gòu)的設(shè)計要求1.機器人手腕的自由度數(shù),應(yīng)根據(jù)作業(yè)需要來設(shè)計。機器人手腕自由度數(shù)目愈多,各關(guān)節(jié)的運動角度愈大,則機器人腕部的靈活性愈高,機器人對對作業(yè)的適應(yīng)能力也愈強。但是,自由度的增加,也必然會使腕部結(jié)構(gòu)更復(fù)雜,機器人的控制更困難,成本也會增加。因此,手腕的自由度數(shù),應(yīng)根據(jù)實際作業(yè)要求來確定。在滿足作業(yè)要求的前提下,應(yīng)使自由度數(shù)盡可能的少。一般的機器人手腕的自由度數(shù)為2至3個,有的需要更多的自由度,而有的機器人手腕不需要自由度,僅憑受臂和腰部的運動就能實現(xiàn)作業(yè)要求的任務(wù)。因此,要具體問題具體分析,考慮機器人的多種布局,運動方案,選擇滿足要求的最簡單的方案。2.機器人腕部安裝在機器人手臂的末端,在設(shè)計機器人手腕時,應(yīng)力求減少其重量和體積,結(jié)構(gòu)力求緊湊。為了減輕機器人腕部的重量,腕部機構(gòu)的驅(qū)動器采用分離傳動。腕部驅(qū)動器一般安裝在手臂上,而不采用直接驅(qū)動,并選用高強度的鋁合金制造。3.機器人手腕要與末端執(zhí)行器相聯(lián),因此,要有標準的聯(lián)接法蘭,結(jié)構(gòu)上要便于裝卸末端執(zhí)行器。4.機器人的手腕機構(gòu)要有足夠的強度和剛度,以保證力與運動的傳遞。5.要設(shè)有可靠的傳動間隙調(diào)整機構(gòu),以減小空回間隙,提高傳動精度。6.手腕各關(guān)節(jié)軸轉(zhuǎn)動要有限位開關(guān),并設(shè)置硬限位,以防止超限造成機械損壞。2.4.2設(shè)計具體采用方案通過對數(shù)控機床上下料作業(yè)的具體分析,考慮數(shù)控機床加工的具體形式及對機械手上下料作業(yè)時的具體要求,在滿足系統(tǒng)工藝要求的前提下提高安全和可靠性,為使機械手的結(jié)構(gòu)盡量簡單,降低控制的難度,本設(shè)計手腕不增加自由度,實踐證明這是完全能滿足作業(yè)要求的,3個自由度來實現(xiàn)機床的上下料完全足夠。具體的手腕(手臂手爪聯(lián)結(jié)梁)結(jié)構(gòu)見圖8。圖8 車床上料機械手手指2.5機械手末端執(zhí)行器(手爪)的結(jié)構(gòu)設(shè)計2.5.1機械手末端執(zhí)行器的設(shè)計要求機器人末端執(zhí)行器是安裝在機器人手腕上用來進行某種操作或作業(yè)的附加裝置。機器人末端執(zhí)行器的種類很多,以適應(yīng)機器人的不同作業(yè)及操作要求。末端執(zhí)行器可分為搬運用、加工用和測量用等。搬運用末端執(zhí)行器是指各種夾持裝置,用來抓取或吸附被搬運的物體。加工用末端執(zhí)行器是帶有噴槍、焊槍、砂輪、銑刀等加工工具的機器人附加裝置,用來進行相應(yīng)的加工作業(yè)。測量用末端執(zhí)行器是裝有測量頭或傳感器的附加裝置,用來進行測量及檢驗作業(yè)。在設(shè)計機器人末端執(zhí)行器時,應(yīng)注意以下問題;1.機器人末端執(zhí)行器是根據(jù)機器人作業(yè)要求來設(shè)計的。一個新的末端執(zhí)行器的出現(xiàn),就可以增加一種機器人新的應(yīng)用場所。因此,根據(jù)作業(yè)的需要和人們的想象力而創(chuàng)造的新的機器人末端執(zhí)行器,將不斷的擴大機器人的應(yīng)用領(lǐng)域。2.機器人末端執(zhí)行器的重量、被抓取物體的重量及操作力的總和機器人容許的負荷力。因此,要求機器人末端執(zhí)行器體積小、重量輕、結(jié)構(gòu)緊湊。3.機器人末端執(zhí)行器的萬能性與專用性是矛盾的。萬能末端執(zhí)行器在結(jié)構(gòu)上很復(fù)雜,甚至很難實現(xiàn),例如,仿人的萬能機器人靈巧手,至今尚未實用化。目前,能用于生產(chǎn)的還是那些結(jié)構(gòu)簡單、萬能性不強的機器人末端執(zhí)行器。從工業(yè)實際應(yīng)用出發(fā),應(yīng)著重開發(fā)各種專用的、高效率的機器人末端執(zhí)行器,加之以末端執(zhí)行器的快速更換裝置,以實現(xiàn)機器人多種作業(yè)功能,而不主張用一個萬能的末端執(zhí)行器去完成多種作業(yè)。因為這種萬能的執(zhí)行器的結(jié)構(gòu)復(fù)雜且造價昂貴。4.通用性和萬能性是兩個概念,萬能性是指一機多能,而通用性是指有限的末端執(zhí)行器,可適用于不同的機器人,這就要求末端執(zhí)行器要有標準的機械接口(如法蘭),使末端執(zhí)行器實現(xiàn)標準化和積木化。5.機器人末端執(zhí)行器要便于安裝和維修,易于實現(xiàn)計算機控制。用計算機控制最方便的是電氣式執(zhí)行機構(gòu)。因此,工業(yè)機器人執(zhí)行機構(gòu)的主流是電氣式,其次是液壓式和氣壓式(在驅(qū)動接口中需要增加電-液或電-氣變換環(huán)節(jié))。2.5.2機器人夾持器的運動和驅(qū)動方式機器人夾持器及機器人手爪。一般工業(yè)機器人手爪,多為雙指手爪。按手指的運動方式,可分為回轉(zhuǎn)型和移動型,按夾持方式來分,有外夾式和內(nèi)撐式兩種。機器人夾持器(手爪)的驅(qū)動方式主要有三種1.氣動驅(qū)動方式這種驅(qū)動系統(tǒng)是用電磁閥來控制手爪的運動方向,用氣流調(diào)節(jié)閥來調(diào)節(jié)其運動速度。由于氣動驅(qū)動系統(tǒng)價格較低,所以氣動夾持器在工業(yè)中應(yīng)用較為普遍。另外,由于氣體的可壓縮性,使氣動手爪的抓取運動具有一定的柔順性,這一點是抓取動作十分需要的。2.電動驅(qū)動方式電動驅(qū)動手爪應(yīng)用也較為廣泛。這種手爪,一般采用直流伺服電機或步進電機,并需要減速器以獲得足夠大的驅(qū)動力和力矩。電動驅(qū)動方式可實現(xiàn)手爪的力與位置控制。但是,這種驅(qū)動方式不能用于有防爆要求的條件下,因為電機有可能產(chǎn)生火花和發(fā)熱。3.液壓驅(qū)動方式液壓驅(qū)動系統(tǒng)傳動剛度大,可實現(xiàn)連續(xù)位置控制。2.5.3機器人夾持器的典型結(jié)構(gòu)1.楔塊杠桿式手爪利用楔塊與杠桿來實現(xiàn)手爪的松、開,來實現(xiàn)抓取工件。2.滑槽式手爪當(dāng)活塞向前運動時,滑槽通過銷子推動手爪合并,產(chǎn)生夾緊動作和夾緊力,當(dāng)活塞向后運動時,手爪松開。這種手爪開合行程較大,適應(yīng)抓取大小不同的物體。3.連桿杠桿式手爪這種手爪在活塞的推力下,連桿和杠桿使手爪產(chǎn)生夾緊(放松)運動,由于杠桿的力放大作用,這種手爪有可能產(chǎn)生較大的夾緊力。通常與彈簧聯(lián)合使用。4.齒輪齒條式手爪這種手爪通過活塞推動齒條,齒條帶動齒輪旋轉(zhuǎn),產(chǎn)生手爪的夾緊與松開動作。5.平行杠桿式手爪采用平行四邊形機構(gòu),因此不需要導(dǎo)軌就可以保證手爪的兩手指保持平行運動,比帶有導(dǎo)軌的平行移動手爪的摩擦力要小很多。2.5.4設(shè)計具體采用方案結(jié)合具體的工作情況,本設(shè)計采用連桿杠桿式的手爪。驅(qū)動活塞往復(fù)移動,通過活塞桿端部齒條,中間齒條及扇形齒條使手指張開或閉合。手指的最小開度由加工工件的直徑來調(diào)定。本設(shè)計按照工件的直徑為80-130mm來設(shè)計。手爪的具體結(jié)構(gòu)形式如圖9所示:圖9 手爪的具體結(jié)構(gòu)2.6機械手的機械傳動機構(gòu)的設(shè)計2.6.1工業(yè)機器人傳動機構(gòu)設(shè)計應(yīng)注意的問題機器人是由多級聯(lián)桿和關(guān)節(jié)組成的多自由度的空間運動機構(gòu)。除直接驅(qū)動型機器人以外,機器人各聯(lián)桿及各關(guān)節(jié)的運動都是由驅(qū)動器經(jīng)過各種機械傳動機構(gòu)進行驅(qū)動的。機器人所采用的傳動機構(gòu)與一般機械的傳動機構(gòu)相類似。常用的機械傳動機構(gòu)主要有螺旋傳動、齒輪傳動、同步帶傳動、高速帶傳動等。由于傳動部件直接影響著機器人的精度、穩(wěn)定性和快速響應(yīng)能力,因此,應(yīng)設(shè)計和選擇滿足傳動間隙小,精度高,低摩擦、體積小、重量輕、運動平穩(wěn)、響應(yīng)速度快、傳遞轉(zhuǎn)矩大、諧振頻率高以及與伺服電動機等其它環(huán)節(jié)的動態(tài)性能相匹配等要求的傳動部件。在設(shè)計機器人的傳動機構(gòu)時要注意以下問題:1.為了提高機器人的運動速度及控制精度,要求機器人各運動部件的重量要輕,慣量要小。因此,機器人的傳動機構(gòu)要力求結(jié)構(gòu)緊湊,重量輕,體積小。2.在傳動鏈及運動副中要采用間隙調(diào)整機構(gòu),以減小反向空回所造成的運動誤差。3.系統(tǒng)傳動部件的靜摩擦力應(yīng)盡可能小,動摩擦力應(yīng)是盡可能小的正斜率,若為負斜率則易產(chǎn)生爬行,精度降低,壽命減小。因此,要采用低摩擦阻力的傳動部件和導(dǎo)向支承部件,如滾珠絲杠副、滾動導(dǎo)向支承等。4.縮短傳動鏈,提高傳動與支承剛度,如用預(yù)緊的方法提高滾珠絲杠副和滾動導(dǎo)軌副的傳動和支承剛度;采用大扭矩、寬調(diào)速的直流或交流伺服電機直接與絲杠螺母副連接,以減小中間傳動機構(gòu);絲杠的支承設(shè)計采用兩端軸向預(yù)緊或預(yù)拉伸支承結(jié)構(gòu)等。5.選用最佳傳動比,以達到提高系統(tǒng)分辨率、減少等效到執(zhí)行元件輸出軸上的等效轉(zhuǎn)動慣量,盡可能提高加速能力。6.縮小反向死區(qū)誤差,如采取消除傳動間隙、減少支承變形等措施。7.適當(dāng)?shù)淖枘岜龋瑱C械零件產(chǎn)生共振時,系統(tǒng)的阻尼越大,最大振幅就越小,且衰減越快;但大阻尼也會使系統(tǒng)的失動量和反轉(zhuǎn)誤差增大,穩(wěn)態(tài)誤差增大,精度降低。故在設(shè)計時要使傳動機構(gòu)的阻尼合適。2.6.2工業(yè)機器人常用的傳動機構(gòu)形式1.齒輪傳動機構(gòu)在機器人中常用的齒輪傳動機構(gòu)有圓柱齒輪,圓錐齒輪,諧波齒輪,擺線針輪及蝸輪蝸桿傳動等。機器人系統(tǒng)中齒輪傳動設(shè)計的一些問題齒輪傳動形式及其傳動比的最佳匹配選擇。齒輪傳動部件是轉(zhuǎn)矩、轉(zhuǎn)速和轉(zhuǎn)向的變換器用于伺服系統(tǒng)的齒輪減速器是一個力矩變換器。齒輪傳動比應(yīng)滿足驅(qū)動部件與負載之間的位移及轉(zhuǎn)矩、轉(zhuǎn)速的匹配要求,其輸入電動機為高轉(zhuǎn)速,低轉(zhuǎn)矩,而輸出則為低轉(zhuǎn)速,高轉(zhuǎn)矩。故齒輪傳動系統(tǒng)要有足夠的剛度,還要求其轉(zhuǎn)動慣量盡量小,以便在獲得同一加速度時所需的轉(zhuǎn)矩小,即在同一驅(qū)動功率時,其加速度響應(yīng)最大。齒輪的嚙合間隙會造成傳動死區(qū)(失動量),若該死區(qū)是閉環(huán)系統(tǒng)中,則可能造成系統(tǒng)不穩(wěn)定,常使系統(tǒng)產(chǎn)生低頻振蕩,因此要盡量采用齒側(cè)間隙小,精度高的齒輪;為盡量降低制造成本,要采用調(diào)整齒側(cè)間隙的方法來消除或減小嚙合間隙,從而提高傳動精度和系統(tǒng)的穩(wěn)定性。2.3 manipulator arm structure designAccording to the requirement, lathe to grab workpiece material arm has three degrees of freedom of the manipulator arm, and adjustable, turning around and drop (or pitch) movement.Turn and lifting movement of the arm is realized by pillar, column the lateral movement known as the shifting arm. Different campaigns have cylinder arm to realize. 2.3.1 manipulator arm design requirementsThe robotic arm role, it is in a certain load and a certain speed, realize the work required in robot in space sport. When designing the robotic arm, follow the following principles;1. Should as far as possible make the robotic arm each joint axis parallel; Perpendicular axis should as far as possible fellowship in a bit, so can make the robot kinematics inverse robot control simplifies, helps.2. The robotic arm structure size should satisfy the requirements of robots work space. Working space shapes and sizes and robot arm length, arm joint rotation range have close relationship. But the robotic arm end work space does not consider the space robot wrist gesture requirements, if robot wrist gesture to specific request, it can realize space arms ends to less than the above did not consider the wrist gesture work space.3. In order to improve the robot movement speed and control accuracy, should keep the robotic arm have enough under the condition of the strength and stiffness, as far as possible on the structure, material manage to reduce the weight of his arm. Strive to choose high intensity of lightweight materials, usually choose high-strength aluminum alloy manufacture a robotic arm. At present, in a foreign country, is also studying with carbon fiber composite materials manufacturing robot arm. Carbon fiber composite materials tensile strength, high ant-vibration sex good, small proportion (its proportion of 1/4 quite to steel, equivalent to aluminum alloy 2/3), but it is expensive, and in the performance stability and manufacturing complex shape workpiece exist problems of technology, it is not in application in practical production. At present more effective method is to use the finite element method for the optimization design of the robotic arm structure. The intensity and stiffness in ensuring the required under the weight of his arm, reduce the robot.4. The robot of each joint bearing clearance as small as possible, in order to reduce to mechanical clearance error motion caused. Therefore, the joints should have reliable operation, easy adjustment bearing clearance adjustment institutions.5. The robot arm relative to rotate the joints should as far as possible under the weight of the balance, the mechanical load and enhance decreases the response speed of the robotic arm movement is very favorable. In the design of robot arm, should as far as possible use in the robot of mechanical and electronic components and devices installed the weight of robotic arm to reduce weight, the unbalanced balancing mechanism when necessary to balance design remnants of unbalanced weight arm.6. The robotic arm on the structure to consider all the joints with certain limit switches and buffering mechanical set blocks, and driving device, transmission mechanism and other components installed.2.3.2 Design specific using schemeManipulator arm (arm) vertical lifting and level of arm (forearm) for linear motion telescopic movement. Linear motion realization is generally pneumatic transmission, hydraulic transmission and motor drive the ball screw to achieve. Considering the weight of carrying workpieces larger, consider the machining quality reaches the 30KG, belong to medium weight of the manipulator, and considering the stability of the dynamic performance and movement of the arm, the stiffness of safety, have higher demand. Comprehensive consideration, two arms driver all choose hydraulic drive mode, through hydraulic cylinder of direct drive, hydraulic cylinder is drive component and executive moving parts, and not to design another executive pieces; And the hydraulic cylinder realizing linear motion control simple, easy to realize the computer control.For hydraulic system can provide great motivation, so in driving force and structural strength are relatively easy to implement, and the key is manipulator of stability and stiffness of the sports meet. Therefore the arm hydraulic cylinder of design principle is the diameter of the cylinder made great point (in overall structures permission), then a nuclear strength.manipulator arm cannot too big, if only by increasing the hydraulic cylinder of cylinder size to increase stiffness, cannot satisfy the system is the rigidity requirement. Therefore, in the design of the additional guide-bar mechanism, forearm add two guide bar, and piston rod together constitute an equilateral triangle section form, try to increase its stiffness; Big arms add four guide bar, a positive quadrilateral layout, to reduce the quality, each guide bar adopts hollow structure. By adding a guide bar, can significantly improve the stability and stiffness of the manipulator movement, good solve structure, reliability problems. 2.4 structure design of robot wristRobot arm movement (including the waist of the seat, and gives the rotary motion) robot end actuators in its working space position, which the movement in the end of the installation of robotic arm, then gives the wrist robot end actuators in the motion of its working space gesture. CaoZuoJi robot wrist is the end of the robot, and the robotic arm with exercise, realize the end of installation of wrist of actuators space with movement trajectory posture, finish the homework action needed.2.4.1 The robot wrist structure design requirements1. Freedom of robot wrist readings, should according to assignments need to design. The more robot wrist freedom, the number of each joint Angle, the robot wrist the greater flexibility of the robot is higher, the adaptability also rightness homework more strong. However, the increase of freedom, also will make the wrist structure more complex, robot control more difficult, costs will increase. Therefore, the wrist of freedom, should according to actual operation degree is required to determine. In meet operational requirements of the premise, should make free degree as less. General robot wrist freedom for 2 to 3 degree, some needs more freedom, and some robot wrist dont need freedom, with only the movement by the arm and waist can achieve operational requirements of the task. Therefore, to the concrete analysis of multiple layouts, consider robot, sports scheme, choose the simplest satisfy the requirements of the plan.2. Robot wrist installed in the end of robot arm robot wrist, in the design, should strive to reduce the weight and volume to compact structure. In order to reduce the weight of robot wrist, wrist institutions drive sperating transmission. Wrist drive general installation in the arm, and do not adopt direct drive, and choose high-strength aluminum alloy manufacture.3. Robot wrist to and end actuators connected, accordingly, want to have the standard connection to facilitate the flange, structure of loading and unloading end actuators.4. Robot wrist institutions should have enough strength and stiffness, strength and movement to ensure the relay.5. To have reliable transmission gap adjusting mechanism, to minimize returned empty clearance, improve the transmission precision.6. The wrist of each joint axis rotation to limited a switch, and set limit to prevent hard out-of-gauge cause mechanical damage.2.4.2 design specific adopts planThrough the nc machine tools for feeding and unloading operations, considering the concrete analysis of concrete form CNC machine processing and manipulator up-down material operations in the specific requirements, and technological requirements of meet the system under the premise of improving safety and reliability of the structure of the manipulator, to make as far as possible simple, reduce the difficulty of the design and control of freedom, not to increase his wrist proved it is fully meet operational requirements of the three degrees of freedom, to realize the up-down material completely enough machine. Specific wrist (arms PAWS coupling beam) structure see figure 8.Figure 8 . Lathe feeding manipulator finger2.5 manipulator actuators (PAWS) structure designing2.5.1 manipulator actuator design requirementsRobot end actuator is installed on the robot wrist used for an operation or additional device homework. Robot end, many different kinds of actuators, in order to adapt to the different assignments and operation robot requirements. End actuators can be divided into move use, processing with with and measurement etc.Move use end actuators refers to all clamping device used to grab or adsorption transported objects.Processing with end actuators with gun, welding torch is milling cutter, grinding wheel, such as the robot machining tool, used for additional device corresponding processing work.With end actuator is measured with the additional head or sensors measuring device used to measuring and test operations.In design robot end actuators, should pay attention to the following questions;1. The robot end actuator is designed according to the operation requirement robot. A new terminal actuators occurrence, can increase a robotic new application places. Accordingly, according to the needs of the homework with people and create a new robot imagination, will continue at actuators expansion of the application field of robot.2. The weight of the robot end actuators to grab objects and the sum of weight and operating force the load force. The robot allow Therefore, request the end-effector actuators small volume, light weight, compact structure.3. The end-effector actuators with specificity is universal sexual paradox. Universal end actuators on the structure is complex, and even harder to achieve, for example, the universal humanoid multisensory dexterous robot hand yet practional utilization. At present, can be used to produce or those simple structure, universal sex not strong robot end actuators. Starting from the industrial application, should focus on the development of special, efficient robot end actuators, plus end actuators, in order to achieve the fast changing device of function, the robot is not advocated homework with a universal end actuators to complete variety of homework. Because this kind of everything the implementation of the structure is complex and expensive.4. Versatility and universal sex are two concepts, universal sex machine, and refers to the multi-energy refers to the end of generality, limited actuators, suitable for different robots, which requires the end actuators have standard machine interface (such as flange), make end actuators realizes standardization and blocks digestion.5. The end-effector actuators to facilitate installation and maintenance, easy to realize the computer control. Use computer control the most convenient is electric type actuator. Therefore, the industrial robot actuators mainstream is electric type, followed by the hydraulic and pneumatic type (in driving interface to increase electricity - liquid or electricity - air transform link).2.5.2 robot grippers sports and drive modeRobot grippers and machine hand claw. General industrial machine hand for double refers to how claws, PAWS. According to finger movement way, can be divided into back transformation and mobile type, press clamping way to points, within the clip type and supporting type two kinds.Robot grippers (PAWS) drive mode basically has 3 kinds1. Pneumatic drive mode this drive system is by electromagnetic valve to control the movement direction of the PAWS, with air regulator to adjust its movement speed. The pneumatic drive system of lower prices, so pneumatic grippers are widely used in industry. In addition, because gas compressibility, contentious hands-on claw grab motion has certain compliant sex, it is very need to grab action.2. Electric drive mode of electric drive PAWS application also more widely. The PAWS, generally USES the dc servo motor or stepping motor, and need to get enough gear reducer driving force and torque. Electric drive mode can realize the force PAWS with position control. But this cannot be used for driving way under the condition of a explosion-proof requirements, because motor may produce sparks and fever.3. Hydraulic drive mode hydraulic drive system transmission can achieve great stiffness.wherever continuous position control.2.5.3 The typical structure robot grippers1. Leveraged wedge PAWSUsing wedge block and levers to realize the pine, open PAWS, come to grab workpiece.2. Slide groove PAWSWhen the pistons forward movement, sliding channel through the pin PAWS merger, pushing produce clamping action and clamping force, when the pistons backward motion, PAWS loosen. This trip is larger, PAWS switching to grab different sizes of the object.3. Connecting rod leveraged PAWSThe PAWS in Detroit, connecting rod and leverage thrust PAWS produce clamped to relax) movement, because (the force-magnifying function, leverage the PAWS might produce larger clamping force. Usually use a combination of and the spring.4. Rack-and pinion type PAWSThe PAWS through the pistons pushing rack, rack driving gear rotating, produce the clamping PAWS with loosen action.5. Parallel leveraged PAWSAdopt parallelogram frame, so there is no need to guide can guarantee to keep the two fingers PAWS with parallel movement, the parallel rails than PAWS friction move to smaller.2.5.4 design specific adopts planCombined with concrete works, this design USES the connecting rod of lever PAWS. Driven by piston, piston rod ends move, the middle rack and rack is fan rack makes the fingers open or closed. The minimum opening finger by machining diameter to the setting. This design according to the workpiece diameter of 80-130mm to design. The concrete structure form PAWS shown as shown in figure 9:Figure 9 The specific structure PAWS2.6 manipulator mechanical transmission design2.6.1 industrial robot transmission mechanism design problems should be paid attention toRobot is by multistage league stem and joint space composed of multi-degree-of-freedom sports organization. In addition to direct drive robot, robot outside each league rod and exercise is of each joint by drive through all kinds of mechanical transmission mechanism driven. Robot adopted the transmission mechanism
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