小型自走式播種機(jī)設(shè)計(汽油機(jī)驅(qū)動)【17張CAD圖紙+PDF圖】
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設(shè)計題目: 小型自走式播種機(jī)(汽油機(jī)驅(qū)動) 姓 名: 王曉良 班級學(xué)號: 2008307335 指導(dǎo)教師: 孫有亮 設(shè)計題目: 小型自走式播種機(jī)(汽油機(jī)驅(qū)動) 姓 名: 王曉良 班級學(xué)號: 2008307335 指導(dǎo)教師: 孫有亮 河北建筑工程學(xué)院畢業(yè)實習(xí)報告系 別 機(jī)械工程系 專 業(yè) 機(jī)械設(shè)計制造及其自動化 班 級 機(jī)083 姓 名 王曉良 學(xué) 號 2008307335 指導(dǎo)教師 孫有亮 實習(xí)成績 畢業(yè)實習(xí)報告一、實習(xí)目的畢業(yè)實習(xí)是工科本科學(xué)生的一個很重要的實踐性教學(xué)環(huán)節(jié)。其任務(wù)是根據(jù)機(jī)械設(shè)計及其自動化專業(yè)的培養(yǎng)目標(biāo),組織學(xué)生參觀相關(guān)的機(jī)械企業(yè)或部門,培養(yǎng)學(xué)生重視實踐、增強理論聯(lián)系實際的觀念,深入調(diào)查研究、拓寬視野、增強面向人才市場、服務(wù)于社會的觀念。我們這半學(xué)期的主要任務(wù)就是進(jìn)行畢業(yè)設(shè)計,把我們大學(xué)四年所學(xué)到的機(jī)械知識理論聯(lián)系現(xiàn)實生產(chǎn)需求進(jìn)行綜合應(yīng)用。這樣即可以進(jìn)一步鞏固所學(xué)的理論知識,又對即將走向的工作崗位作一次實戰(zhàn)性的演習(xí)。因此這次畢業(yè)設(shè)計對于我們這些即將走向工作崗位的大四的畢業(yè)生來說是很重要的。為了給畢業(yè)設(shè)計做一個良好的鋪墊,畢業(yè)實習(xí)是一個不可缺少的環(huán)節(jié)。二、實習(xí)內(nèi)容及進(jìn)度最初是為期兩周的與機(jī)械相關(guān)的英文資料的翻譯,期間我們查閱了大量與設(shè)計相關(guān)的資料,其后就進(jìn)入了畢業(yè)實習(xí)階段。在孫老師的帶領(lǐng)下,我們首先來到了張家口宣化農(nóng)機(jī)公司參觀實習(xí)。宣化農(nóng)機(jī)主營各種玉米,土豆播種和收獲機(jī)械,因此地特殊的地域和氣候環(huán)境我們見到的是中小型農(nóng)機(jī),沒見到大型農(nóng)機(jī),不過見一事之真如,則見事事之真如。不同的廠家不同的產(chǎn)品,使我們開拓了眼界,了解了一個好的設(shè)計不一定是復(fù)雜的,雖然很簡單,但你會說我怎么沒想到,這就是創(chuàng)新和發(fā)散思維。比如保定一家公司的滾筒式播種機(jī)的設(shè)計就只用一個彈簧和九十度折角的小杠桿,就能做到只在接地時排種,雖簡單卻是專利產(chǎn)品。第二階段我們在孫老師的帶領(lǐng)下去唐山一家農(nóng)機(jī)生產(chǎn)工廠。首先對我們進(jìn)行安全教育。老師給我們看安全生產(chǎn)記錄還有事故案例,一些注意事項加血淋淋的案例,盡管我很害怕,不敢聽不敢看,但我不能,我必須聽還要看,還要做筆記,這些血淋淋的案件給人們敲響了警鐘。老師給我們提了好多要求,我們都必須做到,畢竟事故發(fā)生了誰也負(fù)擔(dān)不起。生命是無價的,一旦有嚴(yán)重?fù)p傷是無法恢復(fù)的。安全規(guī)范如下:不允許穿涼鞋進(jìn)廠;進(jìn)廠必須穿長褲; 禁止在廠里吸煙,被發(fā)現(xiàn)者罰款;進(jìn)廠后衣服不準(zhǔn)敞開,外套不準(zhǔn)亂掛在身上,不得背背包進(jìn)廠; 人在廠里不要成堆,不要站在主干道上 注重自身和學(xué)校形象;不準(zhǔn)亂按按扭、開關(guān)。再老師的帶領(lǐng)下我們了學(xué)習(xí)了從了解需求到設(shè)計,工藝制定,生產(chǎn)裝配及測試的流程。老師告誡我們產(chǎn)品設(shè)計是個綜合信息處理的復(fù)雜過程,它最終的結(jié)果是把線條、符號、數(shù)字繪制成合理的設(shè)計圖樣,設(shè)計人員應(yīng)從以下幾個方面綜合考慮; (l)簡化每個零件的形狀,使機(jī)器結(jié)構(gòu)簡單; (2)合并零件的功能,減少零件的種類或數(shù)量; (3)應(yīng)用新結(jié)構(gòu)、新工藝、新材料、新原理來簡化產(chǎn)品結(jié)構(gòu),提高產(chǎn)品的可*性; (4)分解部件,研究其裝配、組裝的最簡單的結(jié)構(gòu); (5)對相似零件進(jìn)行分組; (6)對相似產(chǎn)品按標(biāo)準(zhǔn)數(shù)序列進(jìn)行產(chǎn)品系列化分析; (7)實現(xiàn)產(chǎn)品零件的通用化和標(biāo)準(zhǔn)化。 產(chǎn)品設(shè)計人員提高設(shè)計質(zhì)量的關(guān)鍵在于自覺、主動地學(xué)習(xí)與生產(chǎn)加工過程和加工工藝方面有關(guān)的知識,熟練掌握設(shè)計技巧。好的設(shè)計如果沒有好的工藝是會大打折扣的,工藝沒有最好只有更好,工藝的改進(jìn)是無止境的。改進(jìn)工藝方案: (l)避免沒有必要的切削加工,特別是沒必要的裝夾基準(zhǔn)面的切削加工。焊接件準(zhǔn)備用自動化程度較高的焊接機(jī)器人進(jìn)行焊接時,應(yīng)考慮組成零件的焊前加工,保證焊接件各組成零件之間的相互位置尺寸,否則誤差太大,機(jī)器人將無法自動跟蹤焊接。(2)在保證零部件可*、合理使用的前提下,降低尺寸公差、表面粗糙度、形位公差等加工精度等級要求。 (3)減少零件的彎曲形狀和復(fù)雜程度,降低廢品率和生產(chǎn)制造成本。 (4)型鋼在進(jìn)行長度下料時,盡量把火焰切割改為型鋼剪切下料;一般板料的火焰切割改為用剪板機(jī)剪切下料;長方形條狀工件從四邊剪切改為用條鋼,僅僅是長度上的剪切下料。通過對農(nóng)機(jī)的生產(chǎn)過程參觀,對生產(chǎn)過程的細(xì)節(jié)問題有了更深的認(rèn)識,紙上的來終覺淺。如配合和公差以前以為機(jī)械是粗糙的活,現(xiàn)在才發(fā)現(xiàn)自己是有偏見的,機(jī)械是粗中有細(xì)。軸承配合誤差不能超過倆道(一百道一毫米)。機(jī)架要平行且上面的空要定位精確才能保證安裝省時省力,提高效率。通過互聯(lián)網(wǎng)我們了解了國外的先進(jìn)設(shè)備和制造工藝,我們的差距還很大。三、實習(xí)結(jié)果通過這次的畢業(yè)實習(xí)加上老師在實習(xí)過程中的現(xiàn)場指導(dǎo),使我對其他同學(xué)的課題有了進(jìn)一步的認(rèn)識。更了解了自己的不足生產(chǎn)實習(xí)是教學(xué)計劃中一個重要的實踐性教學(xué)環(huán)節(jié),雖然時間不長,但在實習(xí)的過程中,都學(xué)到了很多東西。在實習(xí)的過程中,我對于各種加工機(jī)床有了更加直觀的了解,通過現(xiàn)場觀看各種零件在機(jī)床上的加工過程,我對機(jī)械制造技術(shù)基礎(chǔ)上所講的夾具、定位方法、加工工序、工步等概念有了更加深入的認(rèn)識;我了解到大多數(shù)零件生產(chǎn)工序大致有兩種,一種是最原始的手搖手柄定位加工,精確性不高,要求工人有很強的操作能力;另一種是數(shù)控控制,由設(shè)備自動控制完成的,操作者只是裝卸輔助,但這個前提是操作者會操作機(jī)器。實習(xí)中,我認(rèn)識到書本理論知識與現(xiàn)實操作的差距,比如,在課堂上時說到自由度、刀具什么的都頭頭是道,可真正到了工廠里一問這個限定了幾個自由度就蒙了,更別說辨認(rèn)刀具了。但是,這也并不是說書本知識與實際生產(chǎn)完全脫節(jié),在實習(xí)參觀過程中,有好多知識都得到了體現(xiàn)。比如,我們在機(jī)械制造技術(shù)基礎(chǔ)中所學(xué)的編制零件加工工序卡片,我在好多零件加工旁都看到了類似的卡片,聽到和見到給人的印象是不一樣的。在這短短的一個月的實習(xí)中,孫老師帶領(lǐng)和教導(dǎo)下以及自已的努力參與學(xué)習(xí),對機(jī)械專業(yè)的各個方面有了深刻的理解和認(rèn)識,并且鞏固了書本上的知識,將理論運用到實際中去,從實際施工中豐富自已的理論知識,學(xué)會運用辯證法去處理機(jī)械生產(chǎn)中遇到的各種問題,我堅信能過這一段時間的實習(xí),所獲得的實踐經(jīng)驗對我終身受益,在我畢業(yè)后的實際工作中將不斷的得到驗證。 四、實習(xí)總結(jié)生產(chǎn)實習(xí)是我們機(jī)械專業(yè)知識結(jié)構(gòu)中不可缺少的組成部分,其目的在于通過實習(xí)使學(xué)生獲得基本生產(chǎn)的感性認(rèn)識,理論聯(lián)系實際,擴(kuò)大我們的知識面;同時又是鍛煉和培養(yǎng)學(xué)生業(yè)務(wù)能力及素質(zhì)的重要渠道,培養(yǎng)當(dāng)代大學(xué)生具有吃苦耐勞的精神,也是學(xué)生接觸社會、了解企業(yè)的一個絕好的機(jī)會。我們的實習(xí)達(dá)到了我們所希望的效果,相信通過此次畢業(yè)實習(xí),會使我們每一位同學(xué)將理論與實際結(jié)合的更緊密,更能夠使我們掌握工程機(jī)械設(shè)計的基本流程、各種參數(shù)的選取、各種影響因素產(chǎn)生的特點;使我們從容的面對以后的設(shè)計和即將踏入的工作崗位。為期一個學(xué)期的畢業(yè)設(shè)計即將結(jié)束,也就意味著我的大學(xué)生活即將結(jié)束。實習(xí)雖然結(jié)束了,再過兩個多月,我們真的就要走上工作崗位了,想想自己大學(xué)四年的生活,有許多讓我回味的思緒,我感謝老師們對我的諄諄教會,在這個春意盎然的季節(jié),伴隨著和煦的春風(fēng)一起飛揚,飛向遠(yuǎn)方,去追逐我的夢想!河 北 建 筑 工 程 學(xué) 院 本科畢業(yè)設(shè)計(論文)題目小型自走式播種機(jī)設(shè)計(汽油機(jī)驅(qū)動)系 別 機(jī)械工程系 學(xué) 科 專 業(yè) 機(jī)械設(shè)計制造及其自動化 班 級 機(jī)083 姓 名 王曉良 指 導(dǎo) 教 師 孫有亮 完 成 日 期 2012年6月17日 河北建筑工程學(xué)院畢業(yè)設(shè)計(論文)開題報告課題名稱小型自走式播種機(jī)設(shè)計(汽油機(jī)驅(qū)動)系 別: 機(jī)械工程系 專 業(yè): 機(jī)械設(shè)計制造及其自動化 班 級: 機(jī)083班 學(xué)生姓名: 王曉良 學(xué) 號: 35號 指導(dǎo)教師: 孫 有 亮 開題時間: 2012年3月23日 課題來源指導(dǎo)教師課題課題類別工程設(shè)計類一、論文資料的準(zhǔn)備1.資料準(zhǔn)備1)在中國知網(wǎng)搜索相關(guān)論文,加深對播種機(jī)各個機(jī)構(gòu)的了解,并熟悉設(shè)計過程。1)在百度搜小型自走式播種機(jī)設(shè)計(汽油機(jī)驅(qū)動)現(xiàn)狀、流行趨勢及加工要求。并加深對播種機(jī)的了解。4)到圖書館借閱機(jī)械設(shè)計相關(guān)資料,了解設(shè)計中需要注意的問題。2. 小型自走式播種機(jī)的種類播種機(jī)的種類很多,一般可按下列方法進(jìn)行分類。1)按播種方式分為撒播機(jī)、條播機(jī)、穴播機(jī)和精密播種機(jī)。2)按適應(yīng)作物分為谷物播種機(jī)、中耕作物播種機(jī)及其他作物播種機(jī)。3)按聯(lián)合作業(yè)分為施肥播種機(jī)、播種中耕通用機(jī)、旋耕播種機(jī)、旋耕鋪膜播種機(jī)。4)按動力聯(lián)接方式分為牽引式、懸掛式和半懸掛式。5)按排種原理分為機(jī)械式、氣力式和離心式播種機(jī)。3.播種機(jī)的歷史概況公元前1世紀(jì),中國已推廣使用耬,這是世界上最早的條播機(jī)具,至今仍在北方旱作區(qū)廣泛應(yīng)用。歐洲第一臺播種機(jī)于1636年在希臘制成。1830年,俄國人在畜力多鏵犁上加裝播種裝置制成犁播機(jī)。英、美等國在1860年以后開始大量生產(chǎn)畜力谷物條播機(jī)。20世紀(jì)以后相繼出現(xiàn)了牽引和懸掛式谷物條播機(jī),以及運用氣力排種的播種機(jī)。1958年挪威出現(xiàn)第一臺離心式播種機(jī),50年代以后逐步發(fā)展各種精密播種機(jī)。 我國在20世紀(jì)50年代從國外引進(jìn)谷物條播機(jī)、棉花播種機(jī)等,60年代先后研制成功懸掛式谷物播種機(jī)(如圖1-3)、離心式播種機(jī)、通用機(jī)架播種機(jī)和氣吸式播種機(jī)等多種機(jī)型,并研制成功了磨紋式排種器。到70年代,已形成播種中耕通用機(jī)和谷物聯(lián)合播種機(jī)兩個系列并投入生產(chǎn)。供谷物、中耕作物、牧草、蔬菜用的各種條播機(jī)和穴播機(jī)都已得到推廣使用。與此同時,還研制成功了多種精密播種機(jī)。4.播種機(jī)的現(xiàn)狀及發(fā)展趨勢播種機(jī)的設(shè)計開發(fā)向大型機(jī)械化和小型專業(yè)化兩個方向發(fā)展。在發(fā)展大功率拖拉機(jī)的地區(qū)趨向于進(jìn)一步增大播種機(jī)的工作幅寬和作業(yè)速度,改善高速作業(yè)下的播種質(zhì)量。小型專業(yè)播種機(jī)將更廣泛地被應(yīng)用于玉米、甜菜、棉花、豆類和某些蔬菜作物。排種器零件的制造精度將不斷提高,并更多地采用可以在發(fā)生異常情況下及時發(fā)出報警信號的電子監(jiān)視裝置。此外,播種方法也在不斷改進(jìn),如采用蠕動泵排種的膠液播種法,可免除不良土壤條件對種子發(fā)芽的影響,還能同時施用農(nóng)藥、肥料等。隨著農(nóng)業(yè)結(jié)構(gòu)調(diào)整的不斷推進(jìn),各地的溫室大棚也越建越多,大棚耕作機(jī)械成了農(nóng)戶耕作的急需品。但國內(nèi)現(xiàn)有的大棚耕作機(jī)械顯現(xiàn)出機(jī)型不多、應(yīng)用不方便的特點,且多為借用現(xiàn)有的露地用小型耕作機(jī)械。近幾年針對溫室、大棚等特殊耕作環(huán)境,國內(nèi)農(nóng)機(jī)生產(chǎn)廠家研制生產(chǎn)了一些小型耕作機(jī)械。但產(chǎn)品大多存在體積大、操作不靈便、在邊角地帶無法工作、漏耕嚴(yán)重、生產(chǎn)效率低、適應(yīng)性較差等缺陷,在作業(yè)性能、可靠性和耐久性等方面也都存在一些問題。由于多數(shù)以柴油機(jī)為動力源,這樣在封閉的條件下,農(nóng)產(chǎn)品也受到排放污染,這樣產(chǎn)量與產(chǎn)品品質(zhì)都受到影響。而且在動力裝置自身上消耗的功率也不可忽視。相比之下,國外設(shè)施農(nóng)業(yè)耕作機(jī)械技術(shù)非常成熟,其機(jī)械作業(yè)性能穩(wěn)定、功能齊全、小巧輕便,但進(jìn)口機(jī)型價格高,一般每臺在7000元以上,而且配件不全,維修服務(wù)跟不上。我國生產(chǎn)的多功能農(nóng)田管理機(jī)一般比國外的同類機(jī)型價格低一半,但其質(zhì)量往往又讓消費者擔(dān)心。因此,國內(nèi)目前急需開發(fā)小型精密或精量播種機(jī)。二、本課題的目的(重點及創(chuàng)新點)本畢業(yè)設(shè)計(論文)課題應(yīng)達(dá)到的目的:1培養(yǎng)學(xué)生綜合應(yīng)用所學(xué)理論知識和技能,分析和解決機(jī)械工程實際問題的能力,熟悉生產(chǎn)技術(shù)工作的一般程序和方法。 2培養(yǎng)學(xué)生懂得工程技術(shù)工作所必須的全局觀念、生產(chǎn)觀念和經(jīng)濟(jì)觀念,樹立正確的設(shè)計思想和嚴(yán)肅認(rèn)真的工作作風(fēng)。3培養(yǎng)學(xué)生調(diào)查研究,查閱技術(shù)言文獻(xiàn)、資料、手冊,進(jìn)行工程計算、圖樣繪制及編寫技術(shù)文件的能力。4. 我國幅員遼闊,地形復(fù)雜,有很多耕地分布在山地和丘陵,不利于大型機(jī)械的作業(yè),我設(shè)計的這款便攜式電動助力播種機(jī)自重輕、適應(yīng)性好,能滿足各種地形的需要,減輕廣大農(nóng)民的勞動強度、提高勞動生產(chǎn)率。5 鞏固擴(kuò)大學(xué)生對大學(xué)基礎(chǔ)課程專業(yè)知識的掌握,提高分析與解決實際問題的能力;提高解決較復(fù)雜工程計算的工作能力;提高計算機(jī)繪圖的工程圖繪制能力。重點:本課題主要包括:小型播種機(jī)的總體設(shè)計、傳動設(shè)計及播種技術(shù)措施、零部件設(shè)計等。該機(jī)結(jié)構(gòu)主要由機(jī)架、動力裝置、操縱機(jī)構(gòu)、開溝器、鎮(zhèn)壓輪、播種量調(diào)節(jié)器和料斗等組成。對總體設(shè)計需對播種機(jī)的工作原理、各機(jī)構(gòu)之間關(guān)系、各零、部件組成及關(guān)系進(jìn)行掌握。創(chuàng)新點:本課題采用汽油機(jī)機(jī),向小型專業(yè)化發(fā)展,較人力播種機(jī)提高工作速度和工作效率,小型汽油機(jī)代替了拖拉機(jī)驅(qū)動播種機(jī),縮小了轉(zhuǎn)彎半徑,減少了碳排放和噪聲污染,降低了作業(yè)成本;四輪驅(qū)動和兩輪驅(qū)動方便轉(zhuǎn)換,增強了松軟土壤作業(yè)的適應(yīng)性和機(jī)動能力。適合在小塊地域及封閉環(huán)境工作,節(jié)能環(huán)保。便于設(shè)施種植和有電力條件的農(nóng)田使用。三、主要內(nèi)容、研究方法、研究思路主要內(nèi)容及要求:本課題任務(wù)的主要內(nèi)容包括:小型播種機(jī)的總體設(shè)計、傳動設(shè)計及播種技術(shù)措施、零部件設(shè)計、電氣控制系統(tǒng)設(shè)計等。本設(shè)計具體要求如下:1.技術(shù)要求:播種深度2060mm連續(xù)可調(diào),播種行距200500mm連續(xù)可調(diào),播種穴距0500mm可調(diào),種子破碎率和播種均勻度符合國家標(biāo)準(zhǔn)。2.設(shè)計要求達(dá)到結(jié)構(gòu)合理、生產(chǎn)成本低、能耗小,效率高,滿足工作性能,而且操作方便的目的。3.工作要求:要求最大生產(chǎn)率為10畝日。研究方法及思路: (1)、根據(jù)工作環(huán)境要求及設(shè)計要求確定其工作原理,選擇機(jī)構(gòu)和傳動方式。 1.考慮大棚的土壤硬度,電動機(jī)功率的選擇可以較低;同時注意電氣線路部分的高度絕緣。 2.零件可直接選擇標(biāo)準(zhǔn)件,其他的小型部件可以自行設(shè)計加工。為了結(jié)構(gòu)的復(fù)雜性,選鏈條作為傳動方式。 3.為了增大整機(jī)的作業(yè)牽引力,故把地輪向后調(diào)。后面的兩個鎮(zhèn)壓輪也改為電機(jī)驅(qū)動,使整機(jī)變?yōu)樗妮嗱?qū)動的形式。 4.因作業(yè)場地和機(jī)身重量都比較小,整轉(zhuǎn)彎的時候可手動轉(zhuǎn)彎,不對轉(zhuǎn)彎進(jìn)行機(jī)械設(shè)計。 (2)初步確定主機(jī)、主要元件或構(gòu)件的基本參數(shù)和技術(shù)性能,如功率、承載、速度、行程或調(diào)節(jié)幅度、外形尺寸等。 1.播種機(jī)的運行速度保持在與人的步行速度。 2.其功率大小,需要根據(jù)實地實驗進(jìn)行測算而確定下來。外形尺寸根據(jù)以往的成功設(shè)計,而選擇兩壟的播種機(jī)機(jī)架。而開溝器,覆土器,播種速度,施肥量等可自行調(diào)節(jié)。 3.通過機(jī)構(gòu)的調(diào)整加大機(jī)身重量等,可以使整機(jī)的地面接觸力更大。 (3)、通常提出幾種不同方案,從技術(shù)和設(shè)計兩個方面比較論證,選擇最理想的。通過實驗,最終確定所選擇的設(shè)計方案?;静シN方式有:條播、穴播(點播)、撤播、精密播種、及聯(lián)合作業(yè)播種機(jī)五種。這幾種機(jī)型的輔助部件基本相同,只是其核心工作部件排種器有較大差異。設(shè)計方案一:汽油機(jī)為動力裝置,單行播種。1.優(yōu)點:結(jié)構(gòu)簡單,速度便于控制,對操作人員技術(shù)要求不高,對環(huán)境無污染。2.缺點:作業(yè)效率較低,能源需要定時補給,不適合長時間的作業(yè)。設(shè)計方案二:汽油機(jī)機(jī)動力,雙行播種。1.優(yōu)點:結(jié)構(gòu)簡單,速度便于控制,無污染,可以方便在大棚環(huán)境中工作。2.缺點:雙行播種,能源利用率低,工作總量較小,對操作距離有限制,需要自行手動轉(zhuǎn)彎。設(shè)計方案三:汽油機(jī)動力,三行播種。1.優(yōu)點:結(jié)構(gòu)簡單,速度便于控制,污染小,工作效率更高。2.缺點:作業(yè)阻力大,工作總量小,制作比較復(fù)雜。 經(jīng)過比較,我選用交流電機(jī)動力,雙行播種,兼顧效率和經(jīng)濟(jì)性。四、總體安排和進(jìn)度(包括階段性工作內(nèi)容及完成日期)3.193.25 完成畢業(yè)實習(xí)報告,開題報告。3.264.08 設(shè)計任務(wù)分析與總體方案的確定。 4.095.20 實施設(shè)計、計算、繪圖、試驗。5.216.17 進(jìn)行計算機(jī)仿真樣機(jī)和優(yōu)化設(shè)計,并編寫設(shè)計說明書。6.186.24 畢業(yè)設(shè)計(論文)答辯及成績評定。五、主要參考文獻(xiàn)1 董剛 李建功 潘鳳章主編.機(jī)械設(shè)計(第三版)北京:機(jī)械工業(yè)出版社19982成大先主編.械設(shè)計圖冊 北京:化學(xué)工業(yè)出版社 19973蔡春源主編.機(jī)電液設(shè)計手冊 北京:機(jī)械工業(yè)出版社 19974徐灝主編.新編機(jī)械設(shè)計師手冊 北京:機(jī)械工業(yè)出版社 19955朱喜林 張代治主編.機(jī)電一體化設(shè)計基礎(chǔ) 北京:科學(xué)出版社 20046求是科技編著.PLC應(yīng)用開發(fā)技術(shù)與工程實踐 北京:人民郵電出版社 20057雷天覺主編.液壓工程手冊 北京:機(jī)械工業(yè)出版社 19908孫桓 陳作模主編.機(jī)械原理(第六版)北京:高等教育出版社 20019王愛玲主編.現(xiàn)代數(shù)控機(jī)床 北京:國防工業(yè)出版社 200310趙如福主編.金屬機(jī)械加工人員手冊(第三版)上海科學(xué)技術(shù)出版社 199011齊麟 張亞雄 黎上威 董學(xué)朱 胡松春編著 蝸桿傳動設(shè)計(上、下冊)北京:機(jī)械工業(yè)出版社 198712齒輪手冊編委會編著 齒輪手冊(上、下冊) 北京:機(jī)械工業(yè)出版社 199013現(xiàn)代機(jī)械傳動手冊編委會編著 現(xiàn)代機(jī)械傳動手冊 北京:機(jī)械工業(yè)出版社 199514郭愛蓮主編.新編機(jī)械工程技術(shù)手冊 經(jīng)濟(jì)日報出版社 199115楊公源主編.機(jī)電控制技術(shù)及應(yīng)用 北京:電子工業(yè)出版社 200516袁任光編著.可編程序控制器選用手冊 北京:機(jī)械工業(yè)出版社 200217饒振綱 王勇衛(wèi)編著.滾珠絲杠副及自鎖裝置 北京:國防工業(yè)出版社 199018陸玉 何在洲 佟延偉主編.機(jī)械設(shè)計課程設(shè)計(第三版)北京:機(jī)械工業(yè)出版社 199919數(shù)字化手冊系列(軟件版)編寫委員會編著.機(jī)械設(shè)計手冊(軟件版)R2.0北京:機(jī)械工業(yè)出版社 1999指導(dǎo)教師意見: 指導(dǎo)教師簽名: 日期:教研室意見:教研室主任簽名: 日期:系意見:系領(lǐng)導(dǎo)簽名: 日期:系蓋章摘要隨著近來溫室大棚的發(fā)展以及環(huán)保發(fā)展意識的日益增強,小型機(jī)的需求就顯得更為重要,尤其是微動力裝置的機(jī)械。然而目前廣泛應(yīng)用的播種機(jī)是以內(nèi)燃機(jī)及人力為動力裝置。本設(shè)計電動小型播種機(jī)與傳統(tǒng)的播種機(jī)相比.新穎之處在于播種機(jī)采用汽油機(jī)為動力裝置,從而改善了人們在田間作業(yè)時的工作環(huán)境,況且更符合環(huán)保發(fā)展的觀點。本設(shè)計主要用于農(nóng)戶田間播種和設(shè)施種植播種.增加部分裝置也可用于施肥、耙磨、除草等田間作業(yè)。詳細(xì)介紹了播種機(jī)的結(jié)構(gòu)組成以及各部件的形式、要求以及功用。詳細(xì)介紹了汽油機(jī)驅(qū)動小型播種機(jī)動力裝置及各部件要求,包括播種機(jī)的動力選擇、機(jī)械傳動的選擇及尺寸、排種輪設(shè)計、排肥輪的設(shè)計、開溝器的設(shè)計、軸的設(shè)計、鏈輪的設(shè)計、其他的各部件設(shè)計以及播種機(jī)的工作要求、播種前的準(zhǔn)備及播種機(jī)的使用等。在設(shè)計中考慮播種深度連續(xù)可調(diào)、播種行距連續(xù)可調(diào)、播種穴距可調(diào)、種子破碎率和播種均勻度符合國家標(biāo)準(zhǔn)。設(shè)計中在考慮實用的同時,兼顧經(jīng)濟(jì)節(jié)約,從而達(dá)到結(jié)構(gòu)合理、生產(chǎn)成本低、能耗小、效率高,而且操作方便的目的。關(guān)鍵詞:汽油機(jī) 小型 播種機(jī)AbstractWith the development of the greenhouse and the consiousness of protecting our ervironment ,boosting up ,the apply of the powy machine becomes more important ,especially the machine with electric power .but at the present time the seeding-machine which is adopted abroadly is drived ba gad engine or man power .this kind of minitype seeding-machine knows from the conventional seeding-machine .Its novel aspect is its drive set which are drived by electric power completly ,so they will improve the work condition ,and accord with euthenics . This design is applied mostly with the farms of the farmers ,they can also used to fertilize、abrade、get rid of grass and so on ,when we incress some equipment .My design introduce the structure of the seeding-machine and the types of many parts 、some request an fuction .My design introduce the drive equipment of the machine and the types of many parts 、request and fuction .My design also introduce the drive equipment of the machine and the request of the parts which consist of the selecting of the power 、the size 、the design of the axial 、chain wheel 、some other parts and so on .We must consider suiting well of the depth 、the row spacing 、the distance of scoop and the rate of seeds breaking up when seeding .In my design ,while thinking over applied ,I give attention to saving econmy ,consequently achieve structure in reason 、the cost of produce lowness 、the cost of power lowness 、the effidiency highness and convenient when operating . KEY WORDS gasoline engine minitype seeding-machine 目錄第1章 前言11.1播種機(jī)的常識和技術(shù)現(xiàn)狀11.2播種方式及常見播種類型31.2.1條播31.2.2穴播41.2.3撒播41.2.4精密播種41.2.5聯(lián)合作業(yè)機(jī)和免耕播種51.3播種工作過程和機(jī)械構(gòu)造51.3.1工作過程51.3.2機(jī)械構(gòu)造61.4播種機(jī)械的發(fā)展趨勢7第2章 總體設(shè)計92.1 概述92.2 設(shè)計任務(wù)102.3 設(shè)計目的102.4 動力方案選擇102.5 設(shè)計題目分析及設(shè)計思想122.6 設(shè)計主參數(shù)及機(jī)構(gòu)類型確定122.6.1工作速度122.6.2播量的確定132.6.3種、肥箱的容積132.6.4機(jī)架設(shè)計142.6.5工作幅度142.6.6 排種、排肥機(jī)構(gòu)設(shè)計142.6.7開溝器設(shè)計182.6.8覆土器設(shè)計222.6.9鎮(zhèn)壓輪設(shè)計232.6.10 地輪設(shè)計23第3章 傳動設(shè)計及播種技術(shù)措施253.1傳動原理簡圖和動力傳遞路線圖253.1.1傳動原理簡圖253.1.2動力傳動路線圖253.2傳動原理253.3技術(shù)措施263.3.1播種均勻性和各行排量一致性措施26 3.3.2降低破種率措施27 3.3.3種肥同播時,肥料的利用率27第4章 零部件設(shè)計28 4.1種箱及肥箱設(shè)計28 4.2開溝器設(shè)計及校核29 4.3排種器314.4地輪參數(shù)確定324.4.1輪子直徑和輪輞寬度的確定324.4.2輪子滾動阻力計算324.5汽油機(jī)的選擇及鏈輪設(shè)計334.5.1汽油機(jī)總功率確定334.5.2汽油機(jī)及減速器的選擇344.5.3傳動比的確定354.5.4鏈輪選擇及設(shè)計計算364.6地輪軸設(shè)計414.7鍵的校核474.8銷的校核484.9軸承的校核49第5章 播種機(jī)使用505.1播種量調(diào)整505.2實際操作說明515.2.1播種作業(yè)前準(zhǔn)備515.2.2播種機(jī)的試播及作業(yè)535.2.3播種機(jī)的保養(yǎng)與保管545.2.4播種質(zhì)量檢查54第6章 畢業(yè)設(shè)計小結(jié)57參考文獻(xiàn)59河北建筑工程學(xué)院畢業(yè)設(shè)計(論文)外文資料翻譯 系別: 機(jī) 械 工 程 系 專業(yè): 機(jī)械設(shè)計制造及其自動化 班級: 機(jī)083班 姓名: 王曉良 學(xué)號: 2008307335 外文出處:Proceedings ofthe 1998 IEEEInternational Conference on Robotics & Automation 附 件:1、外文原文;2、外文資料翻譯譯文。指導(dǎo)教師評語:簽字: 年 月 日Proceedings ofthe 1998 IEEEInternational Conference on Robotics & AutomationLeuven, Belgium May 1998112A practical approach to feedback control for a mobile robot with trailerF. Lamiraux and J.P. LaumondLAAS-CNRSToulouse, Franceflorent ,jpllaas.frAbstractThis paper presents a robust method to control a mobile robot towing a trailer. Both problems of trajectory tracking and steering to a given configuration are addressed. This second issue is solved by an iterative trajectory tracking. Perturbations are taken into account along the motions. Experimental results on the mobile robot Hilare illustrate the validity of our approach.1 IntroductionMotion control for nonholonomic systems have given rise to a lot of work for the past 8 years. Brocketts condition 2 made stabilization about a given configuration a challenging task for such systems, proving that it could not be performed by a simple continuous state feedback. Alternative solutions as time-varying feedback l0, 4, 11, 13, 14, 15, 18 or discontinuous feedback 3 have been then proposed. See 5 for a survey in mobile robot motion control. On the other hand, tracking a trajectory for a nonholonomic system does not meet Brocketts condition and thus it is an easier task. A lot of work have also addressed this problem 6, 7, 8, 12, 16 for the particular case of mobile robots.All these control laws work under the same assumption: the evolution of the system is exactly known and no perturbation makes the system deviate from its trajectory.Few papers dealing with mobile robots control take into account perturbations in the kinematics equations. l however proposed a method to stabilize a car about a configuration, robust to control vector fields perturbations, and based on iterative trajectory tracking.In this paper, we propose a robust scheme based on iterative trajectory tracking, to lead a robot towing a trailer to a configuration. The trajectories are computed by a motion planner described in 17 and thus avoid obstacles that are given in input. In the following.We wont give any development about this planner,we refer to this reference for details. Moreover,we assume that the execution of a given trajectory is submitted to perturbations. The model we chose for these perturbations is very simple and very general.It presents some common points with l.The paper is organized as follows. Section 2 describes our experimental system Hilare and its trailer:two hooking systems will be considered (Figure 1).Section 3 deals with the control scheme and the analysis of stability and robustness. In Section 4, we present experimental results.The presence of obstacle makes the task of reaching a configuration even more difficult and require a path planning task before executing any motion. 2 Description of the systemHilare is a two driving wheel mobile robot. A trailer is hitched on this robot, defining two different systems depending on the hooking device: on system A, the trailer is hitched above the wheel axis of the robot (Figure 1, top), whereas on system B, it is hitched behind this axis (Figure l , bottom). A is the particular case of B, for which = 0. This system is however singular from a control point of view and requires more complex computations. For this reason, we deal separately with both hooking systems. Two motors enable to control the linear and angular velocities (,) of the robot. These velocities are moreover measured by odometric sensors, whereas the angle between the robot and the trailer is given by an optical encoder. The position and orientation(,)of the robot are computed by integrating the former velocities. With these notations, the control system of B is: (1) Figure 1: Hilare with its trailer3 Global control scheme3.1 MotivationWhen considering real systems, one has to take into account perturbations during motion execution.These may have many origins as imperfection of the motors, slippage of the wheels, inertia effects . These perturbations can be modeled by adding a term in the control system (l),leading to a new system of the formwhere may be either deterministic or a random variable.In the first case, the perturbation is only due to a bad knowledge of the system evolution, whereas in the second case, it comes from a random behavior of the system. We will see later that this second model is a better fit for our experimental system.To steer a robot from a start configuration to a goal, many works consider that the perturbation is only the initial distance between the robot and the goal, but that the evolution of the system is perfectly known. To solve the problem, they design an input as a function of the state and time that makes the goal an asymptotically stable equilibrium of the closed loop system. Now, if we introduce the previously defined term in this closed loop system, we dont know what will happen. We can however conjecture that if the perturbation is small and deterministic, the equilibrium point (if there is still one) will be close to the goal, and if the perturbation is a random variable, the equilibrium point will become an equilibrium subset.But we dont know anything about the position of these new equilibrium point or subset.Moreover, time varying methods are not convenient when dealing with obstacles. They can only be used in the neighborhood of the goal and this neighborhood has to be properly defined to ensure collision-free trajectories of the closed loop system. Let us notice that discontinuous state feedback cannot be applied in the case of real robots, because discontinuity in the velocity leads to infinite accelerations.The method we propose to reach a given configuration tn the presence of obstacles is the following. We first build a collision free path between the current configuration and the goal using a collision-freemotion planner described in 17, then we execute the trajectory with a simple tracking control law. At the end of the motion, the robot does never reach exactly the goal because of the various perturbations, but a neighborhood of this goal. If the reached configuration is too far from the goal, we compute another trajectory that we execute as we have done for the former one.We will now describe our trajectory tracking control law and then give robustness issues about our global iterative scheme.3.2 The trajectory tracking control lawIn this section, we deal only with system A. Computations are easier for system B (see Section 3.4).Figure 2: Tracking control law for a single robotA lot of tracking control laws have been proposed for wheeled mobile robots without trailer. One of them 16,a lthough very simple, give excellent results.If are the coordinates of the reference robot in the frame of the real robot (Figure 2), and if are the inputs of the reference trajectory, this control law has the following expression: (2) The key idea of our control law is the following: when the robot goes forward, the trailer need not be stabilized (see below). So we apply (2) to the robot.When it goes backward, we define a virtual robot (Figure 3) which is symmetrical to the real one with respect to the wheel axis of the trailer:Then, when the real robot goes backward, the virtual robot goes forward and the virtual system is kinematically equivalent to the real one. Thus we apply the tracking control law (2) to the virtual robot.Figure 3: Virtual robotA question arises now: is the trailer really always stable when the robot goes forward ? The following section will answer this question.3.3 Stability analysis of the trailerWe consider here the case of a forward motion , the backward motion being equivalent by the virtual robot transformation. Let us denote by a reference trajectory and bythe real motion of the system. We assume that the robot follows exactly its reference trajectory: and we focus our attention on the trailer deviation.The evolution of this deviation is easily deduced from system (1) with (System A): is thus decreasing iff (3)Our system is moreover constrained by the inequalities (4) so that and (3) is equivalent to (5)Figure 4 shows the domain on which is decreasing for a given value of . We can see that this domain contains all positions of the trailer defined by the bounds (4). Moreover, the previous computations permit easily to show that 0 is an asymptotically stable value for the variable .Thus if the real or virtual robot follows its reference forward trajectory, the trailer is stable and will converge toward its own reference trajectory.Figure 4: Stability domain for3.4 Virtual robot for system BWhen the trailer is hitched behind the robot, the former construction is even more simple: we can replace the virtual robot by the trailer. In this case indeed, the velocities of the robot and of the trailer are connected by a one-to-one mapping.The configuration of the virtual robot is then given by the following system:and the previous stability analysis can be applied as well, by considering the motion of the hitching point.The following section addresses the robustness of our iterative scheme.3.5 Robustness of the iterative schemeWe are now going to show the robustness of the iterative scheme we have described above. For this,we need to have a model of the perturbations arising when the robot moves. l model the perturbations by a bad knowledge of constants of the system, leading to deterministic variations on the vector fields. In our experiment we observed random perturbations due for instance to some play in the hitching system. These perturbations are very difficult to model. For this reason,we make only two simple hypotheses about them:where s is the curvilinear abscissa along the planned path, and are respectively the real and reference configurations, is a distance over the configuration space of the system and , are positive constants.The first inequality means that the distance between the real and the reference configurations is proportional to the distance covered on the planned path. The second inequality is ensured by the trajectory tracking control law that prevents the system to go too far away from its reference trajectory. Let us point out that these hypotheses are very realistic and fit a lot of perturbation models.We need now to know the length of the paths generated at each iteration. The steering method we use to compute these paths verifies a topological property accounting for small-time controllability17. This means that if the goal is sufficiently close to the starting configuration, the computed trajectory remains in a neighborhood of the starting configuration. In 9we give an estimate in terms of distance: if and are two sufficiently close configurations, the length of the planned path between them verifieswhere is a positive constant.Thus, if is the sequence of configurations reached after i motions, we have the following inequalities:These inequalities ensure that distCS is upper bounded by a sequence of positive numbers defined byand converging toward after enough iterations.Thus, we do not obtain asymptotical stability of the goal configuration, but this result ensures the existence of a stable domain around this configuration.This result essentially comes from the very general model of perturbations we have chosen. Let us repeat that including such a perturbation model in a time varying control law would undoubtedly make it lose its asymptotical stability.The experimental results of the following section show however, that the converging domain of our control scheme is very small. 4 Experimental resultsWe present now experimental results obtained with our robot Hilare towing a trailer, for both systems A and B. Figures 5 and 6 show examples of first paths computed by the motion planner between the initialFigure 5: System A: the initial and goal configurationsand the first path to be tracked Figure 6: System B: the initial and goal configurations,the first path to be tracked and the final maneuverconfigurations (in black) and the goal configurations (in grey), including the last computed maneuver in the second case. The lengths of both hooking system is the following: ,cm for A and cm,cm for B. Tables 1 and 2 give the position of initial and final configurations and the gaps between the goal and the reached configurations after one motion and two motions, for 3 different experiments. In both cases, the first experiment corresponds to the figure.Empty columns mean that the precision reached after the first motion was sufficient and that no more motion was performed.Comments and Remarks: The results reported in the tables 1 and 2 lead to two main comments. First,the precision reached by the system is very satisfying and secondly the number of iterations is very small (between 1 and 2). In fact, the precision depends a lot on the velocity of the different motions. Here the maximal linear velocity of the robot was 50 cm/s.5 ConclusionWe have presented in this paper a method to steer a robot with one trailer from its initial configuration to a goal given in input of the problem. This method is based on an iterative approach combining open loop and close loop controls. It has been shown robust with respect to a large range of perturbation models. This robustness mainly comes from the topological property of the steering method introduced in 17. Even if the method does not make the robot converge exactly to the goal, the precision reached during real experiments is very satisfying.Table 1: System A: initial and final configurations,gaps between the first and second reached configurations and the goalTable 2: System B: initial and final configurations,gaps between the first and second reached configurations and the goalReferences1M. K. Bennani et P. Rouchon. Robust stabilization of flat and chained systems. in European Control Conference,1995.2R.W. Brockett. Asymptotic stability and feedback stabilization. in Differential Geometric Control Theory,R.W. Brockett, R.S. Millman et H.H. Sussmann Eds,1983.3C. Canudas de Wit, O.J. Sordalen. Exponential stabilization of mobile robots with non holonomic constraints.IEEE Transactions on Automatic Control,Vol. 37, No. 11, 1992.4J. M. Coron. Global asymptotic stabilization for controllable systems without drift. in Mathematics of Control, Signals and Systems, Vol 5, 1992.5A. De Luca, G. Oriolo et C. Samson. Feedback control of a nonholonomic car-like robot, Robot motion planning and control. J.P. Laumond Ed., Lecture Notes in Control and Information Sciences, Springer Verlag, to appear.6R. M. DeSantis. Path-tracking for a tractor-trailerlike robot. in International Journal of Robotics Research,Vol 13, No 6, 1994.7A. Hemami, M. G. Mehrabi et R. M. H. Cheng. Syntheszs of an optimal control law path trackang an mobile robots. in Automatica, Vol 28, No 2, pp 383-387, 1992.8 Y. Kanayama, Y. Kimura, F. Miyazaki et T.Nogushi.A stable tracking control method for an autonomous mobile robot. in IEEE International Conference on Robotics and Automation, Cincinnati, Ohio, 1990.9 F. Lamiraux.Robots mobiles ci remorque : de la planification de chemins d: l e x h t i o n de mouuements,PhD Thesis N7, LAAS-CNRS, Toulouse, September 1997.l0 P. Morin et C. Samson. Application of backstepping techniques to the time-varying exponential stabitisation of chained form systems. European Journal of Control, Vol 3, No 1, 1997.11 J. B. Pomet. Explicit design of time-varying stabilizang control laws for a class of controllable systems without drift. in Systems and Control Letters, North12 M. Sampei, T. Tamura, T. Itoh et M. Nakamichi.Path tracking control of trailer-like mobile robot. in IEEE International Workshop on Intelligent Robots and Systems IROS, Osaka, Japan, pp 193-198, 1991.13 C. Samson. Velocity and torque feedback control of a nonholonomic cart. International Workshop in Adaptative and Nonlinear Control: Issues in Robotics, Grenoble, France, 1990.14 C. Samson. Time-varying feedback stabilization of carlike wheeled mobile robots. in International Journal of Robotics Research, 12(1), 1993.15 C. Samson. Control of chained systems. Application to path following and time-varying poznt-stabilization. in IEEE Transactions on Automatic Control, Vol 40,No 1, 1995.16 C. Samson et K. Ait-Abderrahim. Feedback control of a nonholonomic wheeled cart zncartesaan space.in IEEE International Conference on Robotics and Automation, Sacramento, California, pp 1136-1141,1991.17 S. Sekhavat, F. Lamiraux, J.P. Laumond, G. Bauzil and A. Ferrand. Motion planning and control for Hilare pulling a trader: experzmental issues. IEEE Int. Conf. on Rob. and Autom., pp 3306-3311, 1997.18 O.J. Splrdalen et 0. Egeland. Exponential stabzlzsation of nonholonomic chained systems. in IEEE Transactions on Automatic Control, Vol 40, No 1, 1995. Bolland, Vol 18, pp 147-158, 1992.一種實用的辦法-帶拖車移動機(jī)器人的反饋控制F. Lamiraux and J.P. Laumond拉斯,法國國家科學(xué)研究中心 法國圖盧茲 florent ,jpllaas.fr摘 要本文提出了一種有效的方法來控制帶拖車移動機(jī)器人。軌跡跟蹤和路徑跟蹤這兩個問題已經(jīng)得到解決。接下來的問題是解決迭代軌跡跟蹤。并且把擾動考慮到路徑跟蹤內(nèi)。移動機(jī)器人Hilare的實驗結(jié)果說明了我們方法的有效性。1引言 過去的8年,人們對非完整系統(tǒng)的運動控制做了大量的工作。布洛基2提出了關(guān)于這種系統(tǒng)的一項具有挑戰(zhàn)性的任務(wù),配置的穩(wěn)定性,證明它不能由一個簡單的連續(xù)狀態(tài)反饋。作為替代辦法隨時間變化的反饋10,4,11,13,14,15,18或間斷反饋3也隨之被提出。從 5 移動機(jī)器人的運動控制的一項調(diào)查可以看到。另一方面,非完整系統(tǒng)的軌跡跟蹤不符合布洛基的條件,從而使其這一個任務(wù)更為輕松。許多著作也已經(jīng)給出了移動機(jī)器人的特殊情況的這一問題6,7,8,12,16。所有這些控制律都是工作在相同的假設(shè)下:系統(tǒng)的演變是完全已知和沒有擾動使得系統(tǒng)偏離其軌跡。很少有文章在處理移動機(jī)器人的控制時考慮到擾動的運動學(xué)方程。但是1提出了一種有關(guān)穩(wěn)定汽車的配置,有效的矢量控制擾動領(lǐng)域,并且建立在迭代軌跡跟蹤的基礎(chǔ)上。存在的障礙使得達(dá)到規(guī)定路徑的任務(wù)變得更加困難,因此在執(zhí)行任務(wù)的任何動作之前都需要有一個路徑規(guī)劃。 在本文中,我們在迭代軌跡跟蹤的基礎(chǔ)上提出了一個健全的方案,使得帶拖車的機(jī)器人按照規(guī)定路徑行走。該軌跡計算由規(guī)劃的議案所描述17 ,從而避免已經(jīng)提交了輸入的障礙物。在下面,我們將不會給出任何有關(guān)規(guī)劃的發(fā)展,我們提及這個參考的細(xì)節(jié)。而且,我們認(rèn)為,在某一特定軌跡的執(zhí)行屈服于擾動。我們選擇的這些擾動模型是非常簡單,非常一般。它存在一些共同點1。本文安排如下:第2節(jié)介紹我們的實驗系統(tǒng)Hilare及其拖車:兩個連接系統(tǒng)將被視為(圖1) 。第3節(jié)處理控制方案及分析的穩(wěn)定性和魯棒性。在第4節(jié),我們介紹本實驗結(jié)果 。 圖1帶拖車的Hilare2 系統(tǒng)描述Hilare是一個有兩個驅(qū)動輪的移動機(jī)器人。拖車是被掛在這個機(jī)器人上的,確定了兩個不同的系統(tǒng)取決于連接設(shè)備:在系統(tǒng)A的拖車拴在機(jī)器人的車輪軸中心線上方(圖1 ,頂端),而對系統(tǒng)B是栓在機(jī)器人的車輪軸中心線的后面(圖1 ,底部)。 A對B來說是一種特殊情況,其中 = 0 。這個系統(tǒng)不過單從控制的角度來看,需要更多的復(fù)雜的計算。出于這個原因,我們分開處理掛接系統(tǒng)。兩個馬達(dá)能夠控制機(jī)器人的線速度和角速度(,)。除了這些速度之外,還由傳感器測量,而機(jī)器人和拖車之間的角度,由光學(xué)編碼器給出。機(jī)器人的位置和方向(,)通過整合前的速度被計算。有了這些批注,控制系統(tǒng)B是: (1)3 全球控制方案3.1目的當(dāng)考慮到現(xiàn)實的系統(tǒng),人們就必須要考慮到在運動的執(zhí)行時產(chǎn)生的擾動。 這可能有許多的來源,像有缺陷的電機(jī),輪子的滑動,慣性的影響. 這些擾動可以被設(shè)計通過增加一個周期在控制系統(tǒng)(1) ,得到一個新的系統(tǒng)的形式 在上式中可以是確定性或隨機(jī)變量。 在第一種情況下,擾動僅僅是由于系統(tǒng)演化的不規(guī)則,而在第二種情況下,它來自于該系統(tǒng)一個隨機(jī)行為。我們將看到后來,這第二個模型是一個更適合我們的實驗系統(tǒng)。 為了引導(dǎo)機(jī)器人,從一開始就配置了目標(biāo),許多工程認(rèn)為擾動最初只是機(jī)器人和目標(biāo)之間的距離,但演變的系統(tǒng)是完全眾所周知的。為了解決這個問題,他們設(shè)計了一個可輸入的時間-狀態(tài)函數(shù),使目標(biāo)達(dá)到一個漸近穩(wěn)定平衡的閉環(huán)系統(tǒng)?,F(xiàn)在,如果我們介紹了先前定義周期在這個閉環(huán)系統(tǒng),我們不知道將會發(fā)生什么。但是我們可以猜想,如果擾動很小、是確定的、在平衡點(如果仍然還有一個)將接近目標(biāo),如果擾動是一個隨機(jī)變數(shù),平衡點將成為一個平衡的子集。 但是,我們不知道這些新的平衡點或子集的位置。 此外,在處理障礙時,隨時間變化的方法不是很方便。他們只能使用在附近的目標(biāo),這附近要適當(dāng)界定,以確保無碰撞軌跡的閉環(huán)系統(tǒng)。請注意連續(xù)狀態(tài)反饋不能適用于真實情況下的機(jī)器人,因為間斷的速度導(dǎo)致無限的加速度。 我們建議達(dá)成某一存在障礙特定配置的方法如下。我們首先在當(dāng)前的配置和使用自由的碰撞議案所描述17目標(biāo)之間建立一個自由的碰撞路徑,然后,我們以一個簡單的跟蹤控制率執(zhí)行軌跡。在運動結(jié)束后,因為這一目標(biāo)的各種擾動機(jī)器人從來沒有完全達(dá)到和目標(biāo)的軌跡一致,而是這一目標(biāo)的左右。如果達(dá)到配置遠(yuǎn)離目標(biāo),我們計算另一個我們之前已經(jīng)執(zhí)行過的一個軌跡。 現(xiàn)在我們將描述我們的軌跡跟蹤控制率,然后給出我們的全球迭代方法的魯棒性問題。 3.2軌跡跟蹤控制率 在這一節(jié)中,我們只處理系統(tǒng)A。對系統(tǒng)B容易計算(見第3.4節(jié))。
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