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畢 業(yè) 設(shè) 計(jì)（論 文）任 務(wù) 書
1．本畢業(yè)設(shè)計(jì)（論文）課題應(yīng)達(dá)到的目的：
? ??? 培養(yǎng)學(xué)生綜合運(yùn)用所學(xué)的基礎(chǔ)理論、專業(yè)知識(shí)和專業(yè)基本技能結(jié)合實(shí)際獨(dú)立完成課題的能力；提高其專業(yè)英語水平，計(jì)算機(jī)運(yùn)用水平及書面及口頭表達(dá)能力；訓(xùn)練其初步工程設(shè)計(jì)的能力，為順利走向相關(guān)專業(yè)工作崗位打下基礎(chǔ)。
2．本畢業(yè)設(shè)計(jì)（論文）課題任務(wù)的內(nèi)容和要求（包括原始數(shù)據(jù)、技術(shù)要求、工作要求等）：
? ?? 設(shè)計(jì)一種助老助殘爬樓梯輪椅，要求：1、平地、樓梯兩用；2、平地行駛效率高，操作方便簡單；3、爬樓時(shí)重心波動(dòng)緩和，穩(wěn)定性好；4、不平坦地形下對(duì)系統(tǒng)的重心作適時(shí)調(diào)節(jié)，避免車體傾斜給使用者帶來恐懼。主要包括：總體結(jié)構(gòu)的設(shè)計(jì)；上樓機(jī)構(gòu)的設(shè)計(jì)；下樓機(jī)構(gòu)的設(shè)計(jì)；前后輪的設(shè)計(jì)；關(guān)鍵零部件的結(jié)構(gòu)分析。
畢 業(yè) 設(shè) 計(jì)（論 文）任 務(wù) 書
3．對(duì)本畢業(yè)設(shè)計(jì)（論文）課題成果的要求〔包括圖表、實(shí)物等硬件要求〕：
1.外文參考資料及譯文（附原文）；
2.畢業(yè)設(shè)計(jì)開題報(bào)告一份；
3.編寫設(shè)計(jì)說明書一份；
4.完整的設(shè)計(jì)圖紙一套。?
4．主要參考文獻(xiàn)：
[1]蔡自興.機(jī)器人學(xué).清華大學(xué)出版社,2000.
[2]蘇和平,王人成.一種雙聯(lián)星形輪機(jī)構(gòu)電動(dòng)爬樓梯輪椅的設(shè)計(jì).中國臨床康復(fù).2005.7.
[3]項(xiàng)海籌,烏蘭木齊,張濟(jì)川.手動(dòng)爬樓梯輪椅.復(fù)醫(yī)學(xué)雜志,1994.
[4]魚帥.全方位移動(dòng)爬樓梯機(jī)器人小車研究.江西理工大學(xué)碩士學(xué)位論文.2008.12.
[5]項(xiàng)?；I,烏蘭木齊,張濟(jì)川.手動(dòng)爬樓梯輪椅.中國康復(fù)醫(yī)學(xué)雜志,1994.
[6]李笑,李瑰賢,趙永強(qiáng),陳晶.國內(nèi)外軌道式機(jī)械爬樓梯裝置的研究現(xiàn)狀.機(jī)械設(shè)計(jì)與制造,2005.
[7]王麗娟.行星滾輪轉(zhuǎn)換步行式驅(qū)動(dòng)爬樓梯輪椅設(shè)計(jì).蘇州大學(xué)碩士學(xué)位論文.2010.
[8]吳宗碩.機(jī)械結(jié)構(gòu)設(shè)計(jì).北京：機(jī)械工業(yè)出版社,1998.
[9]孫恒,陳作模,葛文杰.機(jī)械原理（第七版）.高等教育出版社,2005.
[10]濮良貴,紀(jì)名剛.機(jī)械設(shè)計(jì)（第八版）高等教育出版社,2005.
[11]陸豐勤.多功能爬樓梯裝置的研究及控制系統(tǒng)的設(shè)計(jì).南京理大學(xué),2008.
[12]蘇和平,王人成.爬樓梯輪椅的研究進(jìn)展[J].中國康復(fù)醫(yī)學(xué)雜1999.
[13]何清華,平,志雄.能輪椅的研究現(xiàn)狀和發(fā)展趨勢(shì)[J].器人技術(shù)與應(yīng)用,2003.
[14]郭洪紅.工業(yè)機(jī)器人技術(shù).西安電子科技大學(xué)出版社
[15]成大先.機(jī)械設(shè)計(jì)手冊(cè)聯(lián)接與緊固 [M) 北京：化學(xué)工業(yè)出版社，2004
[16]ROEMI FERNANDEZJOAO HESPANHA,Nonliner Control for the Dual Smart Drive Using Backstepping and a Time-Optimal Reference,2005.
[17]Ashish Deshpande Jonathan Luntz,Behaviors for physical cooperation between robots for mobility improvement University of Michigan,2007.
[18] STAIR-CLIMBING WHEELCHAIR.Jayne(American).Oct.21,1986.Patent No.:US 4,816,155
畢 業(yè) 設(shè) 計(jì)（論 文）任 務(wù) 書
5．本畢業(yè)設(shè)計(jì)（論文）課題工作進(jìn)度計(jì)劃：
2015.12.16-2.16.3.9 畢業(yè)實(shí)習(xí)調(diào)研，完成開題報(bào)告、中英文翻譯、論文大綱
2016.3.19-2016.4.25 提交論文草稿，4月中旬中期檢查
2016.4.26-2016.5.6 提交論文定稿
2016.5.6-2016.5.13 準(zhǔn)備答辯
2016.5.13-2016.5.26 答辯，成績?cè)u(píng)定，修改完成最終稿
所在專業(yè)審查意見：
?通過?
負(fù)責(zé)人： ??????????? ?2016? 年??? 1 ?月???13 ?日
?畢 業(yè) 設(shè) 計(jì)（論文） 開 題 報(bào) 告
1．結(jié)合畢業(yè)設(shè)計(jì)（論文）課題情況，根據(jù)所查閱的文獻(xiàn)資料，每人撰寫不少于1000字左右的文獻(xiàn)綜述：
輪椅是康復(fù)的重要工具，它不僅是肢體傷殘者的代步工具，更重要的是使他們借助于輪椅進(jìn)行身體鍛煉和參與社會(huì)活動(dòng)。目前，我國已經(jīng)進(jìn)入老齡化社會(huì)，隨著老人的數(shù)量不斷增加，由于行動(dòng)不便對(duì)輪椅的需求數(shù)量增加，普通的輪椅很難適應(yīng)我國老人上下樓的需要，因?yàn)槲覈蟛糠謽欠拷ㄖ且粤鶎右韵陆ㄖ橹?，該類建筑中沒有安裝電梯，對(duì)于使用輪椅的人來說，上下樓及其不方便，或重心易下滑，單人難上樓，需另建專用車道。因此迫切需要開發(fā)能夠簡便、輕巧的上下樓輪椅。
在我國，每年約有數(shù)十萬老人、殘疾人等需坐輪椅車行走。過去舊式輪椅車存在不能自行上、下樓等問題，使病人的活動(dòng)空間大為縮小。并使監(jiān)護(hù)人看護(hù)病人也很困難。為了給千百萬殘疾人一個(gè)自由、舒適的空間，再加上該產(chǎn)品有著很大實(shí)用性，存在著非常廣闊的市場。于是人們不斷進(jìn)行著艱苦的研究，一代又一代可上樓的輪椅應(yīng)運(yùn)而生。可自上下樓的輪椅能更好的滿足殘疾病人的生活需求，使其可以自己穿梭于沒有助殘?jiān)O(shè)施的高樓大廈內(nèi)。
在我國殘疾人的數(shù)量是可觀的，越來越多的人關(guān)注起他們的日常生活和精神生活。他們渴望能像正常人一樣的生活，渴望能夠獨(dú)立完成一些事情，而不用求助于正常人。這樣殘疾人才會(huì)更有信心的面對(duì)生活，不被歧視，不成為別人的負(fù)擔(dān)。為了滿足殘疾人的需求，也是為了更好的建設(shè)和諧社會(huì)，上樓輪椅成為一個(gè)不可或缺的工具。
爬樓梯裝置的研究已經(jīng)有了較長的歷史，早在19世紀(jì)90年代就已經(jīng)有了此類專利的出現(xiàn)。特別是美、英、日德等發(fā)達(dá)國家早就開始向此領(lǐng)域沖擊，經(jīng)過不斷努力開發(fā)，也出現(xiàn)了一些成果。由于起步較早，它們?cè)谶@方面的技術(shù)也相對(duì)成熟，已經(jīng)推出多種此類產(chǎn)品。但現(xiàn)存產(chǎn)品都還存在各種瑕疵，還沒有一種能做到盡善盡美。我國對(duì)此類裝置的研究起步較晚，在近幾年也有一些成果產(chǎn)生，但距離形成成熟產(chǎn)品還有很長的路要走。
輪椅由手動(dòng)輪椅、電動(dòng)輪椅趨向智能輪椅的方向發(fā)展，但由于他們一般采用傳統(tǒng)的輪式結(jié)構(gòu)，一般僅適合在平地上使用，很少具備爬樓和翻越障礙的能力。樓梯和路障使輪椅的使用受到了很大的限制，很多場合尤其是室外，比如銀行、購物中心門前等或多或少有幾級(jí)臺(tái)階，室內(nèi)也有很多地方?jīng)]有電梯，這也給輪椅用戶造成很多不便。當(dāng)然，國家也花費(fèi)了大量的人力和財(cái)力在某些場所修建了相應(yīng)的輪椅坡道和其他公用設(shè)施以方便殘疾人活動(dòng)。但由于各種因素的影響，這些措施的作用也非常有限。
為了給老年人和殘疾人提供高性能的代步工具，解決樓梯或路障對(duì)他們使用輪椅造成的不便，幫助他們提高行動(dòng)自由度，重新更好的融入社會(huì)，并考慮到我國的基本國情，研究一種價(jià)格適宜、小巧輕便的輪式爬樓梯輪椅裝置具有重大的意義和實(shí)用價(jià)值。
參考文獻(xiàn)
[1]蔡自興.機(jī)器人學(xué).北京：清華大學(xué)出版社.2000
[2]陳立德．機(jī)械設(shè)計(jì)基礎(chǔ)[M]．北京：高等教育出版社.2008
[3]王麗娟.行星滾輪轉(zhuǎn)換步行式驅(qū)動(dòng)爬樓梯輪椅設(shè)計(jì)[D].蘇州：蘇州大學(xué).2010
[4]魚帥.全方位移動(dòng)爬樓梯機(jī)器人小車研究.江西理工大學(xué)碩士學(xué)位論文.2008.12
[5]李笑,李瑰賢,趙永強(qiáng),陳晶.國內(nèi)外軌道式機(jī)械爬樓梯裝置的研究現(xiàn)狀.機(jī)械設(shè)計(jì)與制造.2005
[6]王麗娟.行星滾輪轉(zhuǎn)換步行式驅(qū)動(dòng)爬樓梯輪椅設(shè)計(jì).蘇州大學(xué)碩士學(xué)位論文.2010
[7]吳宗澤.機(jī)械結(jié)構(gòu)設(shè)計(jì).北京：機(jī)械工業(yè)出版社.1998-04
[8]孫恒,陳作模,葛文杰.機(jī)械原理（第七版）.北京：高等教育出版社.2006-05-01
[9]濮良貴,紀(jì)名剛.機(jī)械設(shè)計(jì)（第八版）.北京：高等教育出版社.2010-05-01
[10]陸豐勤.多功能爬樓梯裝置的研究及控制系統(tǒng)的設(shè)計(jì).南京理工大學(xué).2008
[11]蘇和平,王人成.爬樓梯輪椅的研究進(jìn)展[J].北京：中國康復(fù)醫(yī)學(xué)雜志.1999
[12]何清華,平,志雄.輪椅的研究現(xiàn)狀和發(fā)展趨勢(shì)[J].北京：機(jī)器人技術(shù)與應(yīng)用.2003
[13]郭洪紅.工業(yè)機(jī)器人技術(shù)(第二版).西安電子科技大學(xué)出版社.2012-03-01
[14]成大先.機(jī)械設(shè)計(jì)手冊(cè)聯(lián)接與緊固 [M) 北京：化學(xué)工業(yè)出版社.2005
[15]鄧星鐘.機(jī)電傳動(dòng)控制[M].武漢：華中科技大學(xué)出版社.2001-03
[16]孟祥雨.一種星輪式爬樓梯電動(dòng)輪椅設(shè)計(jì)與研究[D].長春：長春工業(yè)大學(xué).2012
畢 業(yè) 設(shè) 計(jì)（論文） 開 題 報(bào) 告
2．本課題要研究或解決的問題和擬采用的研究手段（途徑）：
課題研究內(nèi)容
設(shè)計(jì)一種助老助殘爬樓梯輪椅，要求：1、平地、樓梯兩用；2、平地行駛效率高，操作方便簡單；3、爬樓時(shí)重心波動(dòng)緩和，穩(wěn)定性好；4、不平坦地形下對(duì)系統(tǒng)的重心作適時(shí)調(diào)節(jié)，避免車體傾斜給使用者帶來恐懼。主要包括：總體結(jié)構(gòu)的設(shè)計(jì)；上樓機(jī)構(gòu)的設(shè)計(jì)；下樓機(jī)構(gòu)的設(shè)計(jì)；前后輪的設(shè)計(jì)；關(guān)鍵零部件的結(jié)構(gòu)分析。
課題研究手段
本課題主要是設(shè)計(jì)一款合理、可靠的爬升機(jī)構(gòu)對(duì)于爬樓梯輪椅的功能實(shí)現(xiàn)以及安全性提高方面至關(guān)重要。在爬升機(jī)構(gòu)設(shè)計(jì)過程中，爬樓梯輪椅需要的爬升扭矩較大，這是爬樓裝置普遍面臨的問題，這就需要選擇一套功率較大的動(dòng)力系統(tǒng)并設(shè)計(jì)一套效率較高的傳動(dòng)系統(tǒng)。爬樓梯輪椅在爬樓梯過程中的實(shí)用安全性也是其中的一個(gè)重要指標(biāo)，影響爬樓梯輪椅安全性的一個(gè)重要因素就是其本身的重量。這就要求在結(jié)構(gòu)設(shè)計(jì)過程中在構(gòu)件滿足強(qiáng)度剛度要求的前提下盡量減輕重量，使最終設(shè)計(jì)完成的產(chǎn)品既能滿足使用要求，又要結(jié)構(gòu)緊湊小巧。
Mechanisms And Machine Theory
Introduction to Mechanism：
The function of a mechanism is to transmit or transform motion from one rigid body to another as part of the action of a machine. There are three types of common mechanical devices that can be used as basic elements of a mechanism.
1、Gear system, in which toothed members in contact transmit motion between rotating shafts.
2、Cam system, where a uniform motion of an input member is converted into a nonuniform motion of the output member.
3、Plane and spatial linkages are also useful in creating mechanical motions for a point or rigid body.
A kinematic chain is a system of links, that is, rigid bodies , which are either jointed together or are in contact with one another in a manner that permits them to move relative to one another. If one of the links is fixed and the movement of any other link to a new position will cause each of the other links to move to definite predictable position, the system is a constrained kinematic chain. If one of the links is held fixed and the movement of any other link to a new position will not cause each of the other links to move to a definite predictable position then the system is an unconstrained kinematic chain,
A mechanism or linkage is a constrained kinematic chain, and is a mechanical device that has the purpose of transferring motion and/or force from a source to an output. A linkage consists of links (or bars), generally considered rigid, which are connected by joints, such as pin Cor revolute) or prismatic joints, to form open or closed chains (or loops). Such kinematic chains, with at least one link fixed, become mechanisms if at least two other links remain mobility, or structures if no mobility remains. In other words, a mechanism permits relative motion between its "rigid links"; a structure does not. Since linkages make simple mechanisms and can be designed to perform complex tasks, such as nonlinear motion and force transmission they will receive much attention in mechanism study.
Mechanisms are used in a great variety of machines and devices. The simplest closed-loop linkage is the four-bar linkage, which has three moving links (plus one fixed link) and four pin joints. The link that is connected to the power source or prime mover and has one moving pivot and one ground pivot is called the input link. The output link connects another moving pivot to another ground pivot. The coupler or floating link connected the two moving pivots, thereby "coupling" the input to the output link.
The four-bar linkage has some special configurations created by making one or more links infinite in length. The slider-crank (or crank and slider) mechanism is a four-bar chain with a slider replacing an infinitely long output link. The internal combustion engine is built based on this mechanism. Other forms of four-link mechanisms exist in which a slider is guided on a moving link rather than on a fixed link. These are called inversions of the slider-crank, produced when another link (the crank, coupler, or slider) is fixed link.
Although the four-bar linkage and slider-crank mechanism are very useful and found in thousands of applications, we can see that these linkages have limited performance level. Linkages with more members are often used in more demanding circumstances. However it is often difficult to visualize the movement of a multiloop linkage, especially when other components appear in the same diagram. The first step in the motion analyses of more complicated mechanisms is to sketch the equivalent kinematic or skeleton diagram. The skeleton diagram serves a purpose similar to that of the electrical schematic or circuit diagram .
Organization movement analysis second step: Draws a graphic chart, is must determine the organization the number of degrees of freedom. Based on degree of freedom, but Italy refers needs certain independent inputs the movement number, by determined organization all components are opposite in the ground position. The people have thousands of different types conceivably the link motion gear. You may imagine a bag containing massive link motion gear the component: Two pole groups, three pole groups, four pole groups and so on, as well as components, rotation, motion, cam follower, gear, tooth chain, chain wheel, leather belt, belt pulley and so on. (Sphere movement, screw vice-as well as the permission three dimensional relative motion other connections not yet includes, here, discusses in parallel planes merely plane motion). Moreover you conceivable put these components various types link motion gear possibility which forms in the same place. How exists helps the people to control forms these organizations the rule? In fact, the majority organization duty is requests a sole input to transmit to a sole output. Therefore the single degree of freedom organization uses most one kind of organization type. For example, namely may see by the intuition: Four pole organizations are a single degree of freedom link motion gear.
The picture motion diagram and the determination organization degree of freedom process, is the movement analysis and the synthesis process first stage. In the movement analysis, adds on its characteristic according to the organization geometry shape which possibly knew (for example input angle, speed, angle acceleration and so on) studies the determination concrete organization. On the other hand, the movement synthesis is designs an organization to complete the duty process which an institute requests. In this, chooses the new organization the type and the size is a movement synthesis part. Conceives the relative motion ability, can guess the reason that designs an organization the reason and makes the improvement to a concrete design ability is like this a successful organization scientist's symbol. Although these abilities come from the congenital creativity, however more is because has grasped the technology which enhances from the practice.
The movement analysis：
simple one of most useful organizations is four pole organizations. In on following elaboration majority of content centralism discussion link motion gear, but this procedure is also suitable for the more complex link motion gear.
We already knew four pole organizations have a degree of freedom. About four pole organizations, has the useful more contents which must know? Indeed is some! These pull the Xiao husband criterion including the standard, the transformation concept, the blind spot position (divergence point), branch office, transmission angle, with theirs movement characteristic, including position, speed and acceleration.
Four pole organizations may have one kind of being called as crank rocker organization form, one kind of double rocking lever organization, one kind of double crank (tension bar) does the organization, which one form send in is called as the organization, is decided in two pole movement scopes which (fixed component) connects with the rack. The crank rocker organization input component, the crank may revolve through 360° and the continuous rotation, but outputs the component to make the undulation merely (i.e. swing member). As an exceptional case, in the parallel four pole organization, inputs the pole the length to be equal to outputs the pole the length, the go-between length and the fixed link (rack) length, also is equal. Its input and the output all may make the complete alternation rotation or transform the being called as antiparallel quadrangle organization the overlapping structure. The standard pulls the Xiao husband criterion (theorem) to indicate that,If in four pole organizations, between two poles can do willfully relatively rotates continuously, that, its longest pole length is smaller than sum of with the shortest pole length or is equal to sum of the other two pole length.
Should pay attention: The same four pole organization, may have the different form, which pole is this decided in was stipulated (i.e. makes fixed link) as the rack. The movement transformation process is in the fixed organization transmission chain different member has the different organization rate process. Besides has about the component rotation scope knowledge, but also must have how causes the organization before the manufacture on energy “the revolution” the good measure, that will be very useful. Hardenbergh (Hartenberg) speaks of: “The revolution” is terminology, its significance passes to outputs the component the movement validity. It meant the revolution is steady, in which can in output in the component to have a strength or the torque biggest force component is effective. Not only although the final output strength or the torque are the connecting rod geometric figure functions, moreover also is generally the power or the force of inertia result, that is frequently big to like static strength several times. In order to analyze the idling or in order to easy to obtain how can cause any organization “the revolution” the index, the transmission angle concept is extremely useful. In organization movement period, the transmission angle value is changing. The transmission angle 0° may occur in the special position. Will output the pole but in this special position the movement with not to exert inputs on the pole the strength many to have nothing to do with greatly. In fact, as a result of the movement vice-friction influence, the general basis practical experience, with the transmission angle planning board which is bigger than the rating. The weight link motion gear transmission movement ability matrix foundation definition already studied. A determining factor value (it includes regarding some assigns organization graph, position output movement variable to input variable derivative) is a this link motion gear in concrete position mobility criterion.
If the organization has a degree of freedom (e.g. four pole organizations), then stipulated a location parameter, if the input angle, completely determined this organization stops position (neglect branch office's possibility). We may study one about four pole organization component absolute angular position analysis expression. When analyzes certain positions and (or) certain different organization time, this will be must be much more useful than the geometric figure analysis program, because this expression will cause the automated computation easy to program. The realization organization speed analysis relative velocity law is the speed polygon is one of several effective methods. This end (goes against) the spot to represent on the organization all spots, has the zero speed. From this the line which stipples respectively to the speed polygon in is representing the absolute speed which this organization photograph well should select respectively. In a line connection speed polygon random two points represents is taking on this organization two corresponding spot relative velocity.
機(jī)構(gòu)和機(jī)器原理
機(jī)構(gòu)介紹：
一個(gè)機(jī)構(gòu)的功能是傳送或從一個(gè)剛體變換運(yùn)動(dòng)到另一個(gè)機(jī)器的動(dòng)作的一部分。有三種類型的普通的機(jī)械裝置的，可以用來作為一種機(jī)構(gòu)的基本元素。
1．齒輪裝置。那是在回轉(zhuǎn)軸之間進(jìn)行接觸傳動(dòng)的嚙合構(gòu)件。
2．凸輪裝置。把輸入構(gòu)件的均勻運(yùn)動(dòng)轉(zhuǎn)換成輸出構(gòu)件的非均勻運(yùn)動(dòng)的裝置。
3．平面機(jī)構(gòu)和空間機(jī)構(gòu)也是能使一個(gè)點(diǎn)或一個(gè)剛體產(chǎn)生機(jī)械運(yùn)動(dòng)的有用裝置。
運(yùn)動(dòng)鏈?zhǔn)且粋€(gè)構(gòu)件系統(tǒng)裝置即若干個(gè)剛體，它們或者彼此鉸接或者互相接觸，方式上是允許它們彼此間產(chǎn)生相對(duì)運(yùn)動(dòng)。如果構(gòu)件中的某一構(gòu)件被固定而使任何其他一個(gè)構(gòu)件運(yùn)動(dòng)到新的位置將會(huì)引起其他各個(gè)構(gòu)件也運(yùn)動(dòng)到確定的預(yù)期的位置上的話，該系統(tǒng)裝置就是一個(gè)可約束的運(yùn)動(dòng)鏈。如果構(gòu)件中的某一構(gòu)件仍保持固定而使任一運(yùn)動(dòng)到達(dá)一新的位置而不會(huì)使其他各個(gè)構(gòu)件運(yùn)動(dòng)到一個(gè)確定的預(yù)期的位置上的話，則該系統(tǒng)裝置是一個(gè)非約束運(yùn)動(dòng)鏈。
機(jī)構(gòu)或連桿構(gòu)件是一個(gè)可約束的傳動(dòng)鏈而且是一個(gè)從輸入到輸出以傳遞運(yùn)動(dòng)和（或）力為目的的機(jī)械裝置。連桿機(jī)構(gòu)是由通常被認(rèn)為是剛體構(gòu)件或桿組成的，它們是以銷軸鉸接的，例如用柱銷（圓形的）或棱柱體銷軸鉸接，以便成形開式或閉式（回環(huán)式）的運(yùn)動(dòng)鏈。這樣的運(yùn)動(dòng)鏈在至少有一個(gè)構(gòu)件被固定的條件下：如果至少有兩個(gè)構(gòu)件能保持運(yùn)動(dòng)，就變?yōu)闄C(jī)構(gòu)，如果沒有一個(gè)構(gòu)件能夠運(yùn)動(dòng)，則就成為結(jié)構(gòu)。換句話說，機(jī)構(gòu)是允許其“剛性構(gòu)件”之間相對(duì)運(yùn)動(dòng)，而結(jié)構(gòu)則不能。由于連桿機(jī)構(gòu)做成一簡單機(jī)構(gòu)而且能設(shè)定實(shí)現(xiàn)復(fù)雜的任務(wù)，例如非線性運(yùn)動(dòng)和力的傳遞運(yùn)動(dòng)。它們?cè)跈C(jī)構(gòu)學(xué)研究中將受到更多的關(guān)注。
機(jī)構(gòu)被用于許多許多的機(jī)器和裝置中。最簡單的封閉式的連桿機(jī)構(gòu)就是四桿機(jī)構(gòu)，四桿機(jī)構(gòu)有三個(gè)運(yùn)動(dòng)構(gòu)件（加上一個(gè)固定構(gòu)件）并且有四個(gè)銷軸。連接動(dòng)力源的構(gòu)件即原動(dòng)件，而具有一個(gè)移動(dòng)鉸和一個(gè)固定鉸者叫做輸入構(gòu)件。輸出構(gòu)件將一個(gè)移動(dòng)鉸和另一個(gè)固定鉸連系起來。連接構(gòu)件即浮動(dòng)構(gòu)件將兩個(gè)移動(dòng)的鉸（回轉(zhuǎn)副）連系起來，因而連接構(gòu)件就將輸入傳送到輸出。
四桿機(jī)構(gòu)若使一個(gè)或幾個(gè)構(gòu)件無限長而產(chǎn)生某些特殊的構(gòu)造。曲柄滑塊（即曲柄和滑塊）機(jī)構(gòu)就是一個(gè)四桿機(jī)構(gòu)特例。其以一個(gè)滑塊替換一個(gè)無限長的輸出件。內(nèi)燃機(jī)就是建立在這一機(jī)構(gòu)基礎(chǔ)上。有著另一種形式的四桿機(jī)構(gòu)，其中滑塊是在一運(yùn)動(dòng)的構(gòu)件上導(dǎo)移運(yùn)動(dòng)而不是在一固定構(gòu)件上。這些就被稱為曲柄滑塊機(jī)構(gòu)的變換，它是其中一個(gè)構(gòu)件（曲柄、連桿或滑塊）被固定時(shí)形成的。
雖然四桿機(jī)構(gòu)和曲柄滑塊機(jī)構(gòu)是非常有用而且在成千上萬的應(yīng)用中都可找到。但是我們還看到，這些連桿機(jī)構(gòu)其性能水平的發(fā)揮已經(jīng)受到限制。具有更多構(gòu)件的連桿機(jī)構(gòu)常常用于更多要求的情況中。然而可以設(shè)想多回環(huán)的連桿機(jī)構(gòu)的運(yùn)動(dòng)常常是更為困難的，特別是當(dāng)其他零件出現(xiàn)在同一圖中的時(shí)候，要進(jìn)行更復(fù)雜機(jī)構(gòu)的運(yùn)動(dòng)分析：第一步是繪制一等效運(yùn)動(dòng)圖即示意圖。這示意圖用于電路圖解類似的目的，即僅僅表示機(jī)構(gòu)的主要本質(zhì)的意圖，然而它要體現(xiàn)影響其運(yùn)動(dòng)的關(guān)鍵的尺寸。運(yùn)動(dòng)圖可用兩種形式中的一種：一是草圖，二是比例準(zhǔn)確的運(yùn)動(dòng)圖。
機(jī)構(gòu)運(yùn)動(dòng)分析的第二步：畫一個(gè)圖解圖，是要確定機(jī)構(gòu)的自由度數(shù)。依據(jù)自由度，可意指需要若干個(gè)獨(dú)立輸入的運(yùn)動(dòng)的數(shù)目，以確定機(jī)構(gòu)所有的構(gòu)件相對(duì)于地面的位置。人們可以想象存在數(shù)以千計(jì)的不同類型的連桿機(jī)構(gòu)。你可想象一個(gè)袋子包容大量的連桿機(jī)構(gòu)的組元：二桿組，三桿組，四桿組等等，以及構(gòu)件，回轉(zhuǎn)副，移動(dòng)副，凸輪隨動(dòng)件，齒輪，齒鏈，鏈輪，皮帶，皮帶輪等等。（球形運(yùn)動(dòng)副，螺旋副以及允許三維相對(duì)運(yùn)動(dòng)的其他連接尚未包括進(jìn)去，這里，僅僅討論平行平面內(nèi)的平面運(yùn)動(dòng)）。而且你可以想象一下把這些組元放在一起而形成的各種類連桿機(jī)構(gòu)的可能性。存在如何幫助人們控制所形成這些機(jī)構(gòu)的規(guī)律嗎？實(shí)際上，大多數(shù)機(jī)構(gòu)的任務(wù)是要求一個(gè)單一的輸入被傳遞到一個(gè)單一的輸出。因此單一自由度的機(jī)構(gòu)是使用最多的一種機(jī)構(gòu)類型。例如，由直觀可以看出：四桿機(jī)構(gòu)就是一個(gè)單一自由度的連桿機(jī)構(gòu)。
畫運(yùn)動(dòng)圖和確定機(jī)構(gòu)自由度的過程，就是運(yùn)動(dòng)分析和綜合過程的第一個(gè)階段。在運(yùn)動(dòng)分析中，根據(jù)機(jī)構(gòu)的幾何形狀加上可能知道的其特性（如輸入角、速度，角加速度等）來研究確定具體的機(jī)構(gòu)。另一方面，運(yùn)動(dòng)綜合則是設(shè)計(jì)一個(gè)機(jī)構(gòu)以完成一個(gè)所要求的任務(wù)的過程。于此，選擇新機(jī)構(gòu)的類型和尺寸是運(yùn)動(dòng)綜合的一個(gè)部分。設(shè)想相對(duì)運(yùn)動(dòng)的能力，能推想出之所以這樣設(shè)計(jì)一個(gè)機(jī)構(gòu)的原因和對(duì)一個(gè)具體設(shè)計(jì)進(jìn)行改進(jìn)的能力是一個(gè)成功的機(jī)構(gòu)學(xué)家的標(biāo)志。雖然這些能力來自先天的創(chuàng)造性，然而更多的是因?yàn)檎莆樟藦膶?shí)踐中提高技術(shù)。
運(yùn)動(dòng)分析：
最簡單最有用的機(jī)構(gòu)之一是四桿機(jī)構(gòu)。以下論述中的大部分內(nèi)容集中討論連桿機(jī)構(gòu)上，而該程序也適用于更復(fù)雜的連桿機(jī)構(gòu)。
我們已經(jīng)知道四桿機(jī)構(gòu)具有一個(gè)自由度。關(guān)于四桿機(jī)構(gòu)，有沒有要知道的有用的更多內(nèi)容呢？的確是有的！這些包括格拉肖夫準(zhǔn)則，變換的概念，死點(diǎn)的位置（分歧點(diǎn)），分支機(jī)構(gòu)，傳動(dòng)角，和他們的運(yùn)動(dòng)特征，包括位置，速度和加速度。
四桿機(jī)構(gòu)可具有一種稱作曲柄搖桿機(jī)構(gòu)的形式，一種雙搖桿機(jī)構(gòu)，一種雙曲柄（拉桿）機(jī)構(gòu)，致于稱作哪一種形式的機(jī)構(gòu)，取決于跟機(jī)架（固定構(gòu)件）相連接的兩桿的運(yùn)動(dòng)范圍。曲柄搖桿機(jī)構(gòu)的輸入構(gòu)件，曲柄可旋轉(zhuǎn)通過360°并連續(xù)轉(zhuǎn)動(dòng)，而輸出構(gòu)件僅僅作搖動(dòng)（即搖擺的桿件）。作為一個(gè)特例，在平行四桿機(jī)構(gòu)中，輸入桿的長度等于輸出桿的長度，連接桿的長度和固定桿（機(jī)架）的長度，也是相等的。其輸入和輸出都可以作整周轉(zhuǎn)動(dòng)或者轉(zhuǎn)換成稱作反平行四邊形機(jī)構(gòu)的交叉結(jié)構(gòu)。格拉肖夫準(zhǔn)則（定理）表明：如果四桿機(jī)構(gòu)中，任意兩桿之間能作連續(xù)相對(duì)轉(zhuǎn)動(dòng)，那么，其最長桿長度與最短桿長度之和就小于或等于其余兩桿長度之和。
應(yīng)該注意：相同的四桿機(jī)構(gòu)，可有不同的形式，這取決于哪一根桿被規(guī)定作為機(jī)架（即作固定桿）。運(yùn)動(dòng)變換的過程就是固定機(jī)構(gòu)傳動(dòng)鏈中的不同的桿件以產(chǎn)生不同的機(jī)構(gòu)運(yùn)動(dòng)過程。除了具備關(guān)于構(gòu)件回轉(zhuǎn)范圍的知識(shí)之外，還要具備如何使機(jī)構(gòu)在制造之前就能“運(yùn)轉(zhuǎn)”的良好措施，那將是很有用的。哈登伯格（Hartenberg）說到：“運(yùn)轉(zhuǎn)”是一個(gè)術(shù)語，其意義是傳給輸出構(gòu)件的運(yùn)動(dòng)的有效性。它意味著運(yùn)轉(zhuǎn)平穩(wěn)，其中能在輸出構(gòu)件中產(chǎn)生一個(gè)力或扭矩的最大分力是有效的。雖然最終的輸出力或扭矩不僅是連桿幾何圖形的函數(shù)，而且一般也是動(dòng)力或慣性力的結(jié)果，那常常是大到如靜態(tài)力的幾倍。為了分析低速運(yùn)轉(zhuǎn)或?yàn)榱艘子讷@得如何能使任一機(jī)構(gòu)“運(yùn)轉(zhuǎn)”的指數(shù)，傳動(dòng)角的概念是非常有用的。在機(jī)構(gòu)運(yùn)動(dòng)期間，傳動(dòng)角的值在改變。傳動(dòng)角0°可發(fā)生在特殊位置上。在此特殊位置上輸出桿將不運(yùn)動(dòng)而與施加到輸入桿上的力多大無關(guān)。事實(shí)上，由于運(yùn)動(dòng)副摩擦的影響，一般根據(jù)實(shí)際經(jīng)驗(yàn)，用比規(guī)定值大的傳動(dòng)角去設(shè)計(jì)機(jī)構(gòu)。衡量連桿機(jī)構(gòu)傳遞運(yùn)動(dòng)能力的矩陣基礎(chǔ)的定義已經(jīng)研究出來。一個(gè)決定性因素的值（它含有對(duì)于某個(gè)給定機(jī)構(gòu)圖形，位置的輸出運(yùn)動(dòng)變量對(duì)輸入變量的導(dǎo)數(shù)）是該連桿機(jī)構(gòu)在具體位置中的可動(dòng)性的一個(gè)尺度。
如果機(jī)構(gòu)具有一個(gè)自由度（例如四桿機(jī)構(gòu)），則規(guī)定的一個(gè)位置參數(shù)，如輸入角，就將完全確定該機(jī)構(gòu)休止的位置（忽視分支機(jī)構(gòu)的可能性）。我們可研究一個(gè)關(guān)于四桿機(jī)構(gòu)構(gòu)件絕對(duì)角位置的分析表達(dá)式。當(dāng)分析若干位置和（或）若干不同機(jī)構(gòu)時(shí)候，這將是比幾何圖形分析程序要有用得多，因?yàn)樵摫磉_(dá)式將使自動(dòng)化計(jì)算易于編程。實(shí)現(xiàn)機(jī)構(gòu)速度分析的相對(duì)速度法即速度多邊形是幾種有效的方法之一。這端（頂）點(diǎn)代表著機(jī)構(gòu)上所有的點(diǎn)，具有零速度。從該點(diǎn)到速度多邊形上的各點(diǎn)畫的線代表著該機(jī)構(gòu)上相應(yīng)各點(diǎn)的絕對(duì)速度。一根線連接速度多邊形上的任意兩點(diǎn)就代表著作為該機(jī)構(gòu)上兩個(gè)對(duì)應(yīng)的點(diǎn)的相對(duì)速度。