[工作總結]英文資料

1、.基于虛擬樣機技術的連桿機構的運動與仿真分析1機構學 機構的設計通常是機器設計的核心和首要環(huán)節(jié)。 按照應用力學的觀點，機構學可分為兩個分支：機構運動學和機構動力學。機構運動學只研究機構中各構件的相對運動關系，包括位移、軌跡、速度、加速度等。機構動力學研究運動過程中機構各構件的受力及力與運動的關系。除了機構運動學與動力學兩大分支外，還有一個領域，稱為機構的結構理論，它的研究對象是機構的自由度、結構類型。每種機構的種數。 機構學研究的問題： 第一類是機構分析，對已有機構進行運動學或動力學的分析計算； 第二類是機構綜合，根據給定的運動學或動力學要求，設計機構簡圖。 機構分為開式機構與閉式機構。 開式

2、機構：如串聯(lián)式機械手。 閉式機構：主要有三種，齒輪機構、凸輪機構與連桿機構。由于連桿機構采用低副連接，因而結構簡單，結實耐用，不易磨損，適于高速重載。連桿機構種類繁多，變化多端，能滿足各種運動要求；連桿機構還有其他機構的理論結構原型，是機構的結構理論主要研究對象。同時機器人、機械手等開式機構也是低副機構，與連桿機構息息相關，更推動了連桿機構的發(fā)展。 機構學是一間實用性很強的應用科學，大至各種機器設備，小至人們生活中的各種器具、電器、日常生活用品以及各種玩具，都可以發(fā)現機構學原理。一個機構學問題的解決，有時可以產生很大的經濟效益。 2機構綜合的基本問題 我們把機構運動簡圖的設計稱為機構綜合。 機

3、構綜合必須解決兩個基本問題：第一個是機構結構綜合；第二個是機構尺度綜合。 結構綜合可分為型綜合與數綜合。 型綜合：為了產生某種運動，應選用什么類型的機構，該類機構應當由多少構件及哪些類型的運動副組成，因此稱為機構的選型設計。 數綜合：是一種機構枚舉學。它研究由一定數量的構件和一定類型的運動副能組成一定自由度的運動鏈的種數。目前，機構的選型設計主要還是依靠設計人員的知識和經驗，但現在已經出現了人工智能的專家系統(tǒng)軟件。 尺度綜合是按照給定的運動要求及動力要求，按照已選定的機構類型決定機構簡圖的尺寸，它可分為運動綜合與動力綜合。 傳統(tǒng)的連桿機構綜合即指尺度綜合，它可歸納為三類問題：剛體導引、函數發(fā)生

4、和軌跡發(fā)生。 剛體導引問題：是規(guī)定連桿必須經過的幾個位置來尋求機構桿件的尺寸。 函數發(fā)生問題：是要求機構的輸出變量與輸入變量呈規(guī)定的函數關系。它們可以產生正弦、余弦、積分等關系。 軌跡發(fā)生問題：就是要求連桿上的點產生預期的軌跡。譬如要求一個循環(huán)中的某一段軌跡是圓、橢圓、直線等。 若考慮構件的彈性變形及運動副間隙的動力影響，則綜合起來更復雜一些。 3精確綜合與近似綜合如果將由于制造不精確、構件彈性變形及工作條件等因素造成的機構誤差稱為隨機誤差，那么，設計出來的機構簡圖理論上的運動與要求的預期運動之間的誤差稱為結構誤差。 凡是沒有結構誤差的機構綜合稱為精確綜合； 凡是包含著按某種規(guī)律分布的結構誤差

5、的機構綜合稱為近似綜合。 精確綜合在用多桿機構精確實現軌跡發(fā)生上得到了發(fā)展。譬如人們綜合出反演儀、仿圖儀、直線機構、畫二次曲線的機構以及畫某些高次曲線的機構。在許多情況下，實際上不可能得到既簡單方便又能精確發(fā)生軌跡或函數關系的機構。因此，近似綜合方法得到了很大發(fā)展。在很多場合，用最簡單的四桿機構就可以實現這些任務。 以盡量小的結構誤差，使機構簡圖的理論上的運動再現預期運動，這是機構近似綜合所追求的目標。在數學上這屬于函數逼近問題。常用的函數逼近法有差值逼近法、平方逼近法和最佳逼近法。函數逼近法中。凡是結構誤差為零的點 (也就是機構的位置)稱為精確點。這種保證在某些機構位置上結構誤差為零的綜合方

6、法也稱為精確點綜合。在插值點與插值點之間，結構誤差一般不為零，它按某種規(guī)律分布，一般事先不易控制。這種結構誤差的分布與精確點(插值點)的配置即預先對插值點選擇有關系，可以調整精確點的配置來減小精確點之間的最大絕對誤差。 優(yōu)化方法 (也叫數學規(guī)劃)在機構綜合中得到廣泛的應用。應用這種方法，用不著針對具體問題尋求具體綜合方法，而可以采用一般格式去處理問題。用計算機進行機構的優(yōu)化設計是比較通用的方法。優(yōu)化方法也有它的缺點，譬如，它只能定量地得到機構參數的數值解，而對問題不便做定性分析。傳統(tǒng)的綜合方法，即基于函數逼近理論的解析法與基于運動幾何學的幾何法在這方面卻要優(yōu)越得多。傳統(tǒng)的機構綜合方法的主要發(fā)展

7、方向就是用計算機來取代人工 的繁重運算或作圖，將運動幾何原理以解析形式表達出來，用編程運算取代圖上作業(yè)。Based on dummy specimen technology link motion gear movement and simulation analysis1MechanismDesign is usually the core of the machine design and the primary link.Applied mechanics in accordance with the view, institutions can be divided into two

8、branches of study: kinematics and dynamics. Kinematics only in research institutions of the relative motion of the components, including displacement, trajectory, velocity, acceleration and so on. Dynamics of body movement during the various components of body force and the relationship between forc

9、e and movement. Kinematics and dynamics in addition to the two branches, there is also an area known as the structure theory, it is the body of research freedom, structure type. Number of species in each body.Study the problem of agency：The first category is institutional analysis, there are bodies

10、on the kinematics or dynamics analysis;The second is the synthesis, according to a given kinematic or dynamic requirements, schematic design.Institutions are divided into open and closed institutions institutions.Open institutions: such as the Robot Series.Closed institutions: There are three main t

11、ypes, gear mechanism, cam mechanism and linkage. As the linkage mechanism connecting the use of low-vice, so the structure is simple, strong and durable, not easy to wear, suitable for high-speed heavy-duty. A wide range of linkage and changeable, to meet the requirements of a wide variety of sports

12、; linkage theory there are other institutions prototype structure, the structure is mainly theoretical study. At the same time, robots, robot body is open, such as low-vice agencies, is closely linked with the linkage, but also to promote the development of the linkage. Mechanism is a very practical

13、 application of science, machinery and equipment to a variety of large and small to people's lives in a variety of appliances, electrical appliances, daily necessities and a variety of toys, can be found in Principles of institutions. A body to resolve the issues, and sometimes can produce great

14、 economic benefits. 2Synthesis of the basic problemsWe sketch the design movement known as synthesis.Synthesis of the need to address two basic questions: The first is the integrated body structure; the second is the institutional dimension synthesis.Integrated structure can be divided into a number

15、 of integrated and comprehensive.Comprehensive: In order to have some kind of movement, should be used and what types of institutions, such institutions should be the number of components and what types of movement, deputy of the body is why they are called type design.Several integrated: science is

16、 a body enumeration. Study was conducted by a certain number of its components and a certain type of movement to the composition of a certain degree of freedom, deputy of the kinematic chain of the species. At present, the selection of the design of institutions mainly rely on the designer's kno

17、wledge and experience, but now there have been artificial intelligence expert system software.Synthesis is given in accordance with the requirements of the movement and power requirements, the agencies have been selected in accordance with the type of decision diagram size bodies, it can be divided

18、into a comprehensive and dynamic integrated campaigns.Traditional linkage-scale integrated means comprehensive, it can be summarized into three categories of problems: rigid-body guidance, function and track the occurrence took place.Rigid-body guidance problem: is to provide linkage to go through s

19、everal agencies to find the location of pole size.Function problem: the output is to ask the agency variable input variables and function was provided. They can produce sine, cosine, integral relationship.Trajectory problem: the link is to produce the desired trajectory point. For example, for a per

20、iod of a cycle track is round, oval, straight line and so on.If we are to consider the elastic deformation component and the movement of the driving force for the impact of clearance, the combination is more complicated.3Integrated with similar precision integratedIf inaccurate as a result of manufa

21、cturing, component and the working conditions of elastic deformation caused by such factors as agency error as random error, then, designed a theoretical diagram of the body movement and the requirements of the expected error between the movement known as the structure of the error.All the bodies an

22、d there was no structural error as accurate comprehensive synthesis;All contain some kind of law in accordance with the structure of the distribution of errors as the approximate integrated synthesis.Precision in the use of integrated multi-bar linkage to achieve precise trajectory of the developmen

23、t occurred on. For example, people come up with inversion device, like Fig instrument, straight body, pictures of institutions, as well as conic painting some of the institutions of higher curve.In many cases, virtually impossible to get a simple and convenient and can accurately track the occurrenc

24、e or function of the body. Therefore, the approximate integrated approach to development has been greatly. On many occasions, with the simplest four-bar linkage can be achieved on these tasks.In order to minimize the structure of a small error, so that body movement schematic representation of the t

25、heory is expected to campaign, which is integrated by the body similar to the pursuit of goals. Mathematically it is a function approximation problem. Commonly used approximation has a function of the difference approximation method, square approximation method and the best approximation method. Fun

26、ction approximation method. All the structure of zero-point error (that is, the location of institutions) as the precise point. This ensure that the location of certain institutions on the structure of an integrated approach to the error to zero is also known as precise point integrated. Interpolati

27、on points and interpolation in between, the structure of the general non-zero error, which according to some law of distribution, in general difficult to control in advance. The structure of the distribution of errors and accurate point (interpolation point) configuration that is pre-choose interpolation points are related, you can adjust the precise point of the configuration to reduce the precision between the largest absolute error.Optimization method (also known as mathematical programming) to be integrated in the body a wide range of appli