喜歡就充值下載吧。。資源目錄里展示的文件全都有，，請(qǐng)放心下載，，有疑問(wèn)咨詢QQ:414951605或者1304139763 ======================== 喜歡就充值下載吧。。資源目錄里展示的文件全都有，，請(qǐng)放心下載，，有疑問(wèn)咨詢QQ:414951605或者1304139763 ======================== 河北建筑工程學(xué)院 畢業(yè)實(shí)習(xí)報(bào)告 系 別 機(jī)械工程系 專 業(yè) 機(jī)械設(shè)計(jì)制造及其自動(dòng)化 班 級(jí) 機(jī)083 姓 名 王曉良 學(xué) 號(hào) 2008307335 指導(dǎo)教師 孫有亮 實(shí)習(xí)成績(jī) 畢業(yè)實(shí)習(xí)報(bào)告 一、實(shí)習(xí)目的 畢業(yè)實(shí)習(xí)是工科本科學(xué)生的一個(gè)很重要的實(shí)踐性教學(xué)環(huán)節(jié)。其任務(wù)是根據(jù)機(jī)械設(shè)計(jì)及其自動(dòng)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(shí)踐、增強(qiáng)理論聯(lián)系實(shí)際的觀念，深入調(diào)查研究、拓寬視野、增強(qiáng)面向人才市場(chǎng)、服務(wù)于社會(huì)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(jì)，把我們大學(xué)四年所學(xué)到的機(jī)械知識(shí)理論聯(lián)系現(xiàn)實(shí)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(shí)，又對(duì)即將走向的工作崗位作一次實(shí)戰(zhàn)性的演習(xí)。因此這次畢業(yè)設(shè)計(jì)對(duì)于我們這些即將走向工作崗位的大四的畢業(yè)生來(lái)說(shuō)是很重要的。為了給畢業(yè)設(shè)計(jì)做一個(gè)良好的鋪墊，畢業(yè)實(shí)習(xí)是一個(gè)不可缺少的環(huán)節(jié)。 二、實(shí)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(jì)相關(guān)的資料，其后就進(jìn)入了畢業(yè)實(shí)習(xí)階段。 在孫老師的帶領(lǐng)下，我們首先來(lái)到了張家口宣化農(nóng)機(jī)公司參觀實(shí)習(xí)。宣化農(nóng)機(jī)主營(yíng)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(jiàn)到的是中小型農(nóng)機(jī)，沒(méi)見(jiàn)到大型農(nóng)機(jī)，不過(guò)見(jiàn)一事之真如，則見(jiàn)事事之真如。不同的廠家不同的產(chǎn)品，使我們開(kāi)拓了眼界，了解了一個(gè)好的設(shè)計(jì)不一定是復(fù)雜的，雖然很簡(jiǎn)單，但你會(huì)說(shuō)我怎么沒(méi)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(jì)就只用一個(gè)彈簧和九十度折角的小杠桿，就能做到只在接地時(shí)排種，雖簡(jiǎn)單卻是專利產(chǎn)品。 第二階段我們?cè)趯O老師的帶領(lǐng)下去唐山一家農(nóng)機(jī)生產(chǎn)工廠。首先對(duì)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(xiàng)加血淋淋的案例，盡管我很害怕，不敢聽(tīng)不敢看，但我不能，我必須聽(tīng)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(shuí)也負(fù)擔(dān)不起。生命是無(wú)價(jià)的，一旦有嚴(yán)重?fù)p傷是無(wú)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(zhǎng)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(kāi)，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(kāi)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(jì)，工藝制定，生產(chǎn)裝配及測(cè)試的流程。老師告誡我們產(chǎn)品設(shè)計(jì)是個(gè)綜合信息處理的復(fù)雜過(guò)程，它最終的結(jié)果是把線條、符號(hào)、數(shù)字繪制成合理的設(shè)計(jì)圖樣，設(shè)計(jì)人員應(yīng)從以下幾個(gè)方面綜合考慮； （l）簡(jiǎn)化每個(gè)零件的形狀，使機(jī)器結(jié)構(gòu)簡(jiǎn)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(lái)簡(jiǎn)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(jiǎn)單的結(jié)構(gòu)； （5）對(duì)相似零件進(jìn)行分組； （6）對(duì)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(shí)現(xiàn)產(chǎn)品零件的通用化和標(biāo)準(zhǔn)化。 產(chǎn)品設(shè)計(jì)人員提高設(shè)計(jì)質(zhì)量的關(guān)鍵在于自覺(jué)、主動(dòng)地學(xué)習(xí)與生產(chǎn)加工過(guò)程和加工工藝方面有關(guān)的知識(shí)，熟練掌握設(shè)計(jì)技巧。 好的設(shè)計(jì)如果沒(méi)有好的工藝是會(huì)大打折扣的，工藝沒(méi)有最好只有更好，工藝的改進(jìn)是無(wú)止境的。改進(jìn)工藝方案： （l）避免沒(méi)有必要的切削加工，特別是沒(méi)必要的裝夾基準(zhǔn)面的切削加工。 焊接件準(zhǔn)備用自動(dòng)化程度較高的焊接機(jī)器人進(jìn)行焊接時(shí)，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(wú)法自動(dòng)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(jí)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(zhǎng)度下料時(shí)，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(zhǎng)方形條狀工件從四邊剪切改為用條鋼，僅僅是長(zhǎng)度上的剪切下料。 通過(guò)對(duì)農(nóng)機(jī)的生產(chǎn)過(guò)程參觀，對(duì)生產(chǎn)過(guò)程的細(xì)節(jié)問(wèn)題有了更深的認(rèn)識(shí)，紙上的來(lái)終覺(jué)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(jiàn)的，機(jī)械是粗中有細(xì)。軸承配合誤差不能超過(guò)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(shí)省力，提高效率。通過(guò)互聯(lián)網(wǎng)我們了解了國(guó)外的先進(jìn)設(shè)備和制造工藝，我們的差距還很大。 三、實(shí)習(xí)結(jié)果 通過(guò)這次的畢業(yè)實(shí)習(xí)加上老師在實(shí)習(xí)過(guò)程中的現(xiàn)場(chǎng)指導(dǎo)，使我對(duì)其他同學(xué)的課題有了進(jìn)一步的認(rèn)識(shí)。更了解了自己的不足生產(chǎn)實(shí)習(xí)是教學(xué)計(jì)劃中一個(gè)重要的實(shí)踐性教學(xué)環(huán)節(jié)，雖然時(shí)間不長(zhǎng)，但在實(shí)習(xí)的過(guò)程中，都學(xué)到了很多東西。 在實(shí)習(xí)的過(guò)程中，我對(duì)于各種加工機(jī)床有了更加直觀的了解，通過(guò)現(xiàn)場(chǎng)觀看各種零件在機(jī)床上的加工過(guò)程，我對(duì)《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(shí)；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(qiáng)的操作能力；另一種是數(shù)控控制，由設(shè)備自動(dòng)控制完成的，操作者只是裝卸輔助，但這個(gè)前提是操作者會(huì)操作機(jī)器。 實(shí)習(xí)中，我認(rèn)識(shí)到書本理論知識(shí)與現(xiàn)實(shí)操作的差距，比如，在課堂上時(shí)說(shuō)到自由度、刀具什么的都頭頭是道，可真正到了工廠里一問(wèn)這個(gè)限定了幾個(gè)自由度就蒙了，更別說(shuō)辨認(rèn)刀具了。但是，這也并不是說(shuō)書本知識(shí)與實(shí)際生產(chǎn)完全脫節(jié)，在實(shí)習(xí)參觀過(guò)程中，有好多知識(shí)都得到了體現(xiàn)。比如，我們?cè)凇稒C(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(tīng)到和見(jiàn)到給人的印象是不一樣的。 在這短短的一個(gè)月的實(shí)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(duì)機(jī)械專業(yè)的各個(gè)方面有了深刻的理解和認(rèn)識(shí)，并且鞏固了書本上的知識(shí)，將理論運(yùn)用到實(shí)際中去，從實(shí)際施工中豐富自已的理論知識(shí)，學(xué)會(huì)運(yùn)用辯證法去處理機(jī)械生產(chǎn)中遇到的各種問(wèn)題，我堅(jiān)信能過(guò)這一段時(shí)間的實(shí)習(xí)，所獲得的實(shí)踐經(jīng)驗(yàn)對(duì)我終身受益，在我畢業(yè)后的實(shí)際工作中將不斷的得到驗(yàn)證。 四、實(shí)習(xí)總結(jié) 生產(chǎn)實(shí)習(xí)是我們機(jī)械專業(yè)知識(shí)結(jié)構(gòu)中不可缺少的組成部分，其目的在于通過(guò)實(shí)習(xí)使學(xué)生獲得基本生產(chǎn)的感性認(rèn)識(shí)，理論聯(lián)系實(shí)際，擴(kuò)大我們的知識(shí)面；同時(shí)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(huì)、了解企業(yè)的一個(gè)絕好的機(jī)會(huì)。我們的實(shí)習(xí)達(dá)到了我們所希望的效果，相信通過(guò)此次畢業(yè)實(shí)習(xí)，會(huì)使我們每一位同學(xué)將理論與實(shí)際結(jié)合的更緊密，更能夠使我們掌握工程機(jī)械設(shè)計(jì)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(diǎn)；使我們從容的面對(duì)以后的設(shè)計(jì)和即將踏入的工作崗位。 為期一個(gè)學(xué)期的畢業(yè)設(shè)計(jì)即將結(jié)束，也就意味著我的大學(xué)生活即將結(jié)束。實(shí)習(xí)雖然結(jié)束了，再過(guò)兩個(gè)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(duì)我的諄諄教會(huì)，在這個(gè)春意盎然的季節(jié)，伴隨著和煦的春風(fēng)一起飛揚(yáng)，飛向遠(yuǎn)方，去追逐我的夢(mèng)想！ 河 北 建 筑 工 程 學(xué) 院 本科畢業(yè)設(shè)計(jì)（論文） 題 目 小型自走式播種機(jī)設(shè)計(jì) (汽油機(jī)驅(qū)動(dòng)) 系 別 機(jī)械工程系 學(xué) 科 專 業(yè) 機(jī)械設(shè)計(jì)制造及其自動(dòng)化 班 級(jí) 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(jì)（論文）開(kāi)題報(bào)告 課題 名稱 小型自走式播種機(jī)設(shè)計(jì)（汽油機(jī)驅(qū)動(dòng)） 系 別： 機(jī)械工程系 專 業(yè)： 機(jī)械設(shè)計(jì)制造及其自動(dòng)化 班 級(jí)： 機(jī)083班 學(xué)生姓名： 王曉良 學(xué) 號(hào)： 35號(hào) 指導(dǎo)教師： 孫 有 亮 開(kāi)題時(shí)間： 2012年3月23日 課題來(lái)源 指導(dǎo)教師課題 課題類別 工程設(shè)計(jì)類 一、論文資料的準(zhǔn)備 1.資料準(zhǔn)備 1）在中國(guó)知網(wǎng)搜索相關(guān)論文，加深對(duì)播種機(jī)各個(gè)機(jī)構(gòu)的了解，并熟悉設(shè)計(jì)過(guò)程。 1）在百度搜小型自走式播種機(jī)設(shè)計(jì)（汽油機(jī)驅(qū)動(dòng)）現(xiàn)狀、流行趨勢(shì)及加工要求。并加深對(duì)播種機(jī)的了解。 4）到圖書館借閱機(jī)械設(shè)計(jì)相關(guān)資料，了解設(shè)計(jì)中需要注意的問(wèn)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(dòng)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(guó)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(tái)播種機(jī)于1636年在希臘制成。1830年，俄國(guó)人在畜力多鏵犁上加裝播種裝置制成犁播機(jī)。英、美等國(guó)在1860年以后開(kāi)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(yùn)用氣力排種的播種機(jī)。1958年挪威出現(xiàn)第一臺(tái)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(guó)在20世紀(jì)50年代從國(guó)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(gè)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(shí)，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(shì) 播種機(jī)的設(shè)計(jì)開(kāi)發(fā)向大型機(jī)械化和小型專業(yè)化兩個(gè)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(shí)發(fā)出報(bào)警信號(hào)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(dòng)泵排種的膠液播種法，可免除不良土壤條件對(duì)種子發(fā)芽的影響，還能同時(shí)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(guó)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(diǎn)，且多為借用現(xiàn)有的露地用小型耕作機(jī)械。 近幾年針對(duì)溫室、大棚等特殊耕作環(huán)境，國(guó)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(wú)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(wèn)題。由于多數(shù)以柴油機(jī)為動(dòng)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(dòng)力裝置自身上消耗的功率也不可忽視。 相比之下，國(guó)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(jià)格高，一般每臺(tái)在7000元以上，而且配件不全，維修服務(wù)跟不上。我國(guó)生產(chǎn)的多功能農(nóng)田管理機(jī)一般比國(guó)外的同類機(jī)型價(jià)格低一半，但其質(zhì)量往往又讓消費(fèi)者擔(dān)心。因此，國(guó)內(nèi)目前急需開(kāi)發(fā)小型精密或精量播種機(jī)。 二、本課題的目的（重點(diǎn)及創(chuàng)新點(diǎn)） 本畢業(yè)設(shè)計(jì)（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(shí)和技能，分析和解決機(jī)械工程實(shí)際問(wèn)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(shù)立正確的設(shè)計(jì)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(cè)，進(jìn)行工程計(jì)算、圖樣繪制及編寫技術(shù)文件的能力。 4. 我國(guó)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(jì)的這款便攜式電動(dòng)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(dòng)強(qiáng)度、提高勞動(dòng)生產(chǎn)率。 5． 鞏固擴(kuò)大學(xué)生對(duì)大學(xué)基礎(chǔ)課程專業(yè)知識(shí)的掌握，提高分析與解決實(shí)際問(wèn)題的能力；提高解決較復(fù)雜工程計(jì)算的工作能力；提高計(jì)算機(jī)繪圖的工程圖繪制能力。 重點(diǎn)：本課題主要包括：小型播種機(jī)的總體設(shè)計(jì)、傳動(dòng)設(shè)計(jì)及播種技術(shù)措施、零部件設(shè)計(jì)等。該機(jī)結(jié)構(gòu)主要由機(jī)架、動(dòng)力裝置、操縱機(jī)構(gòu)、開(kāi)溝器、鎮(zhèn)壓輪、播種量調(diào)節(jié)器和料斗等組成。對(duì)總體設(shè)計(jì)需對(duì)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(diǎn)：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(dòng)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(dòng)和兩輪驅(qū)動(dòng)方便轉(zhuǎn)換，增強(qiáng)了松軟土壤作業(yè)的適應(yīng)性和機(jī)動(dòng)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(jì)、傳動(dòng)設(shè)計(jì)及播種技術(shù)措施、零部件設(shè)計(jì)、電氣控制系統(tǒng)設(shè)計(jì)等。 本設(shè)計(jì)具體要求如下： 1.技術(shù)要求：播種深度20~60mm連續(xù)可調(diào)，播種行距200~500mm連續(xù)可調(diào)，播種穴距0~500mm可調(diào)，種子破碎率和播種均勻度符合國(guó)家標(biāo)準(zhǔn)。 2.設(shè)計(jì)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(jì)要求確定其工作原理，選擇機(jī)構(gòu)和傳動(dòng)方式。 1.考慮大棚的土壤硬度，電動(dòng)機(jī)功率的選擇可以較低；同時(shí)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(jì)加工。為了結(jié)構(gòu)的復(fù)雜性，選鏈條作為傳動(dòng)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(gè)鎮(zhèn)壓輪也改為電機(jī)驅(qū)動(dòng)，使整機(jī)變?yōu)樗妮嗱?qū)動(dòng)的形式。 4.因作業(yè)場(chǎng)地和機(jī)身重量都比較小，整轉(zhuǎn)彎的時(shí)候可手動(dòng)轉(zhuǎn)彎，不對(duì)轉(zhuǎn)彎進(jìn)行機(jī)械設(shè)計(jì)。 （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(yùn)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(shí)地實(shí)驗(yàn)進(jìn)行測(cè)算而確定下來(lái)。外形尺寸根據(jù)以往的成功設(shè)計(jì)，而選擇兩壟的播種機(jī)機(jī)架。而開(kāi)溝器，覆土器，播種速度，施肥量等可自行調(diào)節(jié)。 3.通過(guò)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(jì)兩個(gè)方面比較論證，選擇最理想的。通過(guò)實(shí)驗(yàn)，最終確定所選擇的設(shè)計(jì)方案。基本播種方式有：條播、穴播（點(diǎn)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(jì)方案一：汽油機(jī)為動(dòng)力裝置，單行播種。 1.優(yōu)點(diǎn)：結(jié)構(gòu)簡(jiǎn)單，速度便于控制，對(duì)操作人員技術(shù)要求不高，對(duì)環(huán)境無(wú)污染。 2.缺點(diǎn)：作業(yè)效率較低，能源需要定時(shí)補(bǔ)給，不適合長(zhǎng)時(shí)間的作業(yè)。 設(shè)計(jì)方案二：汽油機(jī)機(jī)動(dòng)力，雙行播種。 1.優(yōu)點(diǎn)：結(jié)構(gòu)簡(jiǎn)單，速度便于控制，無(wú)污染，可以方便在大棚環(huán)境中工作。 2.缺點(diǎn)：雙行播種，能源利用率低，工作總量較小，對(duì)操作距離有限制，需要自行手動(dòng)轉(zhuǎn)彎。 設(shè)計(jì)方案三：汽油機(jī)動(dòng)力，三行播種。 1.優(yōu)點(diǎn)：結(jié)構(gòu)簡(jiǎn)單，速度便于控制，污染小，工作效率更高。 2.缺點(diǎn)：作業(yè)阻力大，工作總量小，制作比較復(fù)雜。 經(jīng)過(guò)比較，我選用交流電機(jī)動(dòng)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） 3.19～3.25 完成畢業(yè)實(shí)習(xí)報(bào)告，開(kāi)題報(bào)告。 3.26～4.08 設(shè)計(jì)任務(wù)分析與總體方案的確定。 4.09～5.20 實(shí)施設(shè)計(jì)、計(jì)算、繪圖、試驗(yàn)。 5.21～6.17 進(jìn)行計(jì)算機(jī)仿真樣機(jī)和優(yōu)化設(shè)計(jì)，并編寫設(shè)計(jì)說(shuō)明書。 6.18～6.24 畢業(yè)設(shè)計(jì)（論文）答辯及成績(jī)?cè)u(píng)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(jì)（第三版）北京：機(jī)械工業(yè)出版社1998 [2]成大先主編.械設(shè)計(jì)圖冊(cè) 北京：化學(xué)工業(yè)出版社 1997 [3]蔡春源主編.機(jī)電液設(shè)計(jì)手冊(cè) 北京：機(jī)械工業(yè)出版社 1997 [4]徐灝主編.新編機(jī)械設(shè)計(jì)師手冊(cè) 北京：機(jī)械工業(yè)出版社 1995 [5]朱喜林 張代治主編.機(jī)電一體化設(shè)計(jì)基礎(chǔ) 北京：科學(xué)出版社 2004 [6]求是科技編著.PLC應(yīng)用開(kāi)發(fā)技術(shù)與工程實(shí)踐 北京：人民郵電出版社 2005 [7]雷天覺(jué)主編.液壓工程手冊(cè) 北京：機(jī)械工業(yè)出版社 1990 [8]孫桓 陳作模主編.機(jī)械原理（第六版）北京：高等教育出版社 2001 [9]王愛(ài)玲主編.現(xiàn)代數(shù)控機(jī)床 北京：國(guó)防工業(yè)出版社 2003 [10]趙如福主編.金屬機(jī)械加工人員手冊(cè)（第三版）上?？茖W(xué)技術(shù)出版社 1990 [11]齊麟 張亞雄 黎上威 董學(xué)朱 胡松春編著 蝸桿傳動(dòng)設(shè)計(jì)（上、下冊(cè)）北京：機(jī)械工業(yè)出版社 1987 [12]齒輪手冊(cè)編委會(huì)編著 齒輪手冊(cè)（上、下冊(cè)） 北京：機(jī)械工業(yè)出版社 1990 [13]《現(xiàn)代機(jī)械傳動(dòng)手冊(cè)》編委會(huì)編著 現(xiàn)代機(jī)械傳動(dòng)手冊(cè) 北京：機(jī)械工業(yè)出版社 1995 [14]郭愛(ài)蓮主編.新編機(jī)械工程技術(shù)手冊(cè) 經(jīng)濟(jì)日?qǐng)?bào)出版社 1991 [15]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 2005 [16]袁任光編著.可編程序控制器選用手冊(cè) 北京：機(jī)械工業(yè)出版社 2002 [17]饒振綱 王勇衛(wèi)編著.滾珠絲杠副及自鎖裝置 北京:國(guó)防工業(yè)出版社 1990 [18]陸玉 何在洲 佟延偉主編.機(jī)械設(shè)計(jì)課程設(shè)計(jì)（第三版）北京：機(jī)械工業(yè)出版社 1999 [19]數(shù)字化手冊(cè)系列（軟件版）編寫委員會(huì)編著.機(jī)械設(shè)計(jì)手冊(cè)（軟件版）R2.0北京：機(jī)械工業(yè)出版社 1999 指導(dǎo)教師意見(jiàn)： 指導(dǎo)教師簽名： 日期： 教研室意見(jiàn)： 教研室主任簽名： 日期： 系意見(jiàn)： 系領(lǐng)導(dǎo)簽名： 日期： 系蓋章 設(shè)計(jì)題目： 小型自走式播種機(jī)（汽油機(jī)驅(qū)動(dòng)） 姓 名： 王曉良 班級(jí)學(xué)號(hào)： 2008307335 指導(dǎo)教師： 孫有亮 設(shè)計(jì)題目： 小型自走式播種機(jī)（汽油機(jī)驅(qū)動(dòng)） 姓 名： 王曉良 班級(jí)學(xué)號(hào)： 2008307335 指導(dǎo)教師： 孫有亮 目錄 第1章 前言··········································································1 1.1播種機(jī)的常識(shí)和技術(shù)現(xiàn)狀·······················································1 1.2播種方式及常見(jiàn)播種類型·······················································3 1.2.1條播·············································································3 1.2.2穴播·············································································4 1.2.3撒播·············································································4 1.2.4精密播種·······································································4 1.2.5聯(lián)合作業(yè)機(jī)和免耕播種························································5 1.3播種工作過(guò)程和機(jī)械構(gòu)造·······················································5 1.3.1工作過(guò)程·······································································5 1.3.2機(jī)械構(gòu)造·······································································6 1.4播種機(jī)械的發(fā)展趨勢(shì)·····························································7 第2章 總體設(shè)計(jì)····································································9 2.1 概述···············································································9 2.2 設(shè)計(jì)任務(wù)········································································10 2.3 設(shè)計(jì)目的········································································10 2.4 動(dòng)力方案選擇···································································10 2.5 設(shè)計(jì)題目分析及設(shè)計(jì)思想·····················································12 2.6 設(shè)計(jì)主參數(shù)及機(jī)構(gòu)類型確定··················································12 2.6.1工作速度······································································12 2.6.2播量的確定···································································13 2.6.3種、肥箱的容積······························································13 2.6.4機(jī)架設(shè)計(jì)······································································14 2.6.5工作幅度······································································14 2.6.6 排種、排肥機(jī)構(gòu)設(shè)計(jì)·························································14 2.6.7開(kāi)溝器設(shè)計(jì)····································································18 2.6.8覆土器設(shè)計(jì)···································································22 2.6.9鎮(zhèn)壓輪設(shè)計(jì)····································································23 2.6.10 地輪設(shè)計(jì)····································································23 第3章 傳動(dòng)設(shè)計(jì)及播種技術(shù)措施···········································25 3.1傳動(dòng)原理簡(jiǎn)圖和動(dòng)力傳遞路線圖····································25 3.1.1傳動(dòng)原理簡(jiǎn)圖·································································25 3.1.2動(dòng)力傳動(dòng)路線圖······························································25 3.2傳動(dòng)原理·········································································25 3.3技術(shù)措施·········································································26 3.3.1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(shí)，肥料的利用率··················································27 第4章 零部件設(shè)計(jì)·······························································28 4.1種箱及肥箱設(shè)計(jì)·································································28 4.2開(kāi)溝器設(shè)計(jì)及校核······························································29 4.3排種器···········································································31 4.4地輪參數(shù)確定···································································32 4.4.1輪子直徑和輪輞寬度的確定·················································32 4.4.2輪子滾動(dòng)阻力計(jì)算····························································32 4.5汽油機(jī)的選擇及鏈輪設(shè)計(jì)······················································33 4.5.1汽油機(jī)總功率確定····························································33 4.5.2汽油機(jī)及減速器的選擇······················································34 4.5.3傳動(dòng)比的確定·································································35 4.5.4鏈輪選擇及設(shè)計(jì)計(jì)算·························································36 4.6地輪軸設(shè)計(jì)······································································41 4.7鍵的校核·········································································47 4.8銷的校核·········································································48 4.9軸承的校核······································································49 第5章 播種機(jī)使用·······························································50 5.1播種量調(diào)整······································································50 5.2實(shí)際操作說(shuō)明···································································51 5.2.1播種作業(yè)前準(zhǔn)備······························································51 5.2.2播種機(jī)的試播及作業(yè)·························································53 5.2.3播種機(jī)的保養(yǎng)與保管·························································54 5.2.4播種質(zhì)量檢查·································································54 第6章 畢業(yè)設(shè)計(jì)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(jì)（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(jì)制造及其自動(dòng)化 班級(jí)： 機(jī)083班 姓名： 王曉良 學(xué)號(hào)： 2008307335 外文出處：Proceedings ofthe 1998 IEEE International 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(píng)語(yǔ)： 簽字： 年 月 日 Proceedings ofthe 1998 IEEE International Conference on Robotics & Automation Leuven, Belgium May 1998 1 12 A practical approach to feedback control for a mobile robot with trailer F. Lamiraux and J.P. Laumond LAAS-CNRS Toulouse, France {florent ,jpl}@laas.fr Abstract This 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 Introduction Motion control for nonholonomic systems have given rise to a lot of work for the past 8 years. Brockett’s 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 Brockett’s 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 won’t 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 system Hilare 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 trailer 3 Global control scheme 3.1 Motivation When 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 form where 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 don't 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 don't 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 law In 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 robot A 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 robot A 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 trailer We 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 for 3.4 Virtual robot for system B When 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 scheme We 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 controllability[17]. 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 [9]we give an estimate in terms of distance: if and are two sufficiently close configurations, the length of the planned path between them verifies where 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 by and 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 results We 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 initial Figure 5: System A: the initial and goal configurations and the first path to be tracked Figure 6: System B: the initial and goal configurations, the first path to be tracked and the final maneuver configurations (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 Conclusion We 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. 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Laumond 拉斯，法國(guó)國(guó)家科學(xué)研究中心 法國(guó)圖盧茲 {florent ,jpl}@laas.fr 摘 要 本文提出了一種有效的方法來(lái)控制帶拖車移動(dòng)機(jī)器人。軌跡跟蹤和路徑跟蹤這兩個(gè)問(wèn)題已經(jīng)得到解決。接下來(lái)的問(wèn)題是解決迭代軌跡跟蹤。并且把擾動(dòng)考慮到路徑跟蹤內(nèi)。移動(dòng)機(jī)器人Hilare的實(shí)驗(yàn)結(jié)果說(shuō)明了我們方法的有效性。 1引言 過(guò)去的8年，人們對(duì)非完整系統(tǒng)的運(yùn)動(dòng)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(xiàng)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(gè)簡(jiǎn)單的連續(xù)狀態(tài)反饋。作為替代辦法隨時(shí)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(dòng)機(jī)器人的運(yùn)動(dòng)控制的一項(xiàng)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(gè)任務(wù)更為輕松。許多著作也已經(jīng)給出了移動(dòng)機(jī)器人的特殊情況的這一問(wèn)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(méi)有擾動(dòng)使得系統(tǒng)偏離其軌跡。很少有文章在處理移動(dòng)機(jī)器人的控制時(shí)考慮到擾動(dòng)的運(yùn)動(dòng)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(dòng)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(dòng)作之前都需要有一個(gè)路徑規(guī)劃。 在本文中，我們?cè)诘壽E跟蹤的基礎(chǔ)上提出了一個(gè)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(jì)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(huì)給出任何有關(guān)規(guī)劃的發(fā)展，我們提及這個(gè)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(dòng)。我們選擇的這些擾動(dòng)模型是非常簡(jiǎn)單，非常一般。它存在一些共同點(diǎn)[1]。 本文安排如下：第2節(jié)介紹我們的實(shí)驗(yàn)系統(tǒng)Hilare及其拖車：兩個(gè)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(shí)驗(yàn)結(jié)果 。 圖1帶拖車的Hilare 2 系統(tǒng)描述 Hilare是一個(gè)有兩個(gè)驅(qū)動(dòng)輪的移動(dòng)機(jī)器人。拖車是被掛在這個(gè)機(jī)器人上的，確定了兩個(gè)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(duì)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(duì)B來(lái)說(shuō)是一種特殊情況，其中 = 0 。這個(gè)系統(tǒng)不過(guò)單從控制的角度來(lái)看，需要更多的復(fù)雜的計(jì)算。出于這個(gè)原因，我們分開(kāi)處理掛接系統(tǒng)。兩個(gè)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(cè)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(guò)整合前的速度被計(jì)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(shí)的系統(tǒng)，人們就必須要考慮到在運(yùn)動(dòng)的執(zhí)行時(shí)產(chǎn)生的擾動(dòng)。 這可能有許多的來(lái)源，像有缺陷的電機(jī)，輪子的滑動(dòng)，慣性的影響... 這些擾動(dòng)可以被設(shè)計(jì)通過(guò)增加一個(gè)周期在控制系統(tǒng)（1） ，得到一個(gè)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(dòng)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(lái)自于該系統(tǒng)一個(gè)隨機(jī)行為。我們將看到后來(lái)，這第二個(gè)模型是一個(gè)更適合我們的實(shí)驗(yàn)系統(tǒng)。 為了引導(dǎo)機(jī)器人，從一開(kāi)始就配置了目標(biāo)，許多工程認(rèn)為擾動(dòng)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(gè)問(wèn)題，他們?cè)O(shè)計(jì)了一個(gè)可輸入的時(shí)間-狀態(tài)函數(shù)，使目標(biāo)達(dá)到一個(gè)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(gè)閉環(huán)系統(tǒng)，我們不知道將會(huì)發(fā)生什么。但是我們可以猜想，如果擾動(dòng)很小、是確定的、在平衡點(diǎn)（如果仍然還有一個(gè)）將接近目標(biāo)，如果擾動(dòng)是一個(gè)隨機(jī)變數(shù)，平衡點(diǎn)將成為一個(gè)平衡的子集。 但是，我們不知道這些新的平衡點(diǎn)或子集的位置。 此外，在處理障礙時(shí)，隨時(shí)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(wú)碰撞軌跡的閉環(huán)系統(tǒng)。請(qǐng)注意連續(xù)狀態(tài)反饋不能適用于真實(shí)情況下的機(jī)器人，因?yàn)殚g斷的速度導(dǎo)致無(wú)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(gè)自由的碰撞路徑，然后，我們以一個(gè)簡(jiǎn)單的跟蹤控制率執(zhí)行軌跡。在運(yùn)動(dòng)結(jié)束后，因?yàn)檫@一目標(biāo)的各種擾動(dòng)機(jī)器人從來(lái)沒(méi)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(jì)算另一個(gè)我們之前已經(jīng)執(zhí)行過(guò)的一個(gè)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(wèn)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(duì)系統(tǒng)B容易計(jì)算（見(jiàn)第3.4節(jié)）。