轎車(chē)機(jī)械式變速器設(shè)計(jì)畢業(yè)論文-資料下載頁(yè)
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【正文】 良好的基礎(chǔ)。參考文獻(xiàn)[1] [M].北京：清華大學(xué)出版社，2001[2] [M].北京：機(jī)械工業(yè)出版社，2000[3] [M].沈陽(yáng)：東北大學(xué)出版社 2003[4] [M].上海：上?？茖W(xué)技術(shù)出版社 2003[5] [M].，1997[6] [M].:人民交通出版社，2001[7] 清華大學(xué) [M].:機(jī)械工業(yè)出版社，1998[8] 鐘建國(guó) 廖耘 [M].長(zhǎng)沙:中南大學(xué)出版社，2002[9] 肖盛云 [M].重慶:重慶大學(xué)出版社，1997[10] 梁治明. 材料力學(xué)[M]. 遼寧：高等教育出版社出版，1985.[11] The Motor Vehicle Newton Steeda,Garrett,1962[12] 陳家瑞 汽車(chē)構(gòu)造（下冊(cè)） 第2版 機(jī)械工業(yè)出版社 2000.（08）[13] Bostwick C C，Szadkowski Vibrations DuringEngagements of Dry Friction Clutches[R].SAE Technical Paper，982846:689~701 [14] Adolf Goetzberger, Christopher materials,past,present,future. Solar Energy Materialsamp。Solar Cells,62(2000):119[15] , of SolarGradesilicon refining Intermetallics,2003(11):11111117附 錄我們提出了一種新的手段，能使自由行態(tài)的曲面造型相互影響。這種造型方法提供給用戶們的是一種無(wú)限的，柔順的，沒(méi)有固定控制的曲面，從而取代了那種固定的網(wǎng)狀控制點(diǎn)。用戶們自由地實(shí)施那些經(jīng)過(guò)處理的適合操作指令的控制點(diǎn)和曲線。這些復(fù)雜的曲面形狀也許會(huì)因?yàn)樵黾痈嗟目刂泣c(diǎn)和曲面而變得沒(méi)有明顯的界限。在利用那些控制的約束，這些曲面的形狀會(huì)在一種或多種的簡(jiǎn)單的標(biāo)準(zhǔn)下而變得十分確定，就比如光滑度。我們解決導(dǎo)致強(qiáng)迫變形的最優(yōu)化問(wèn)題的方法停留在一個(gè)允許不一致的B型活動(dòng)曲線規(guī)曲面細(xì)分曲面描寫(xiě)上。自動(dòng)細(xì)分是用來(lái)確保那些約束是滿足要求，而不去執(zhí)行錯(cuò)誤的領(lǐng)域。高效的數(shù)字化表示會(huì)在公式和描述問(wèn)題上的線性開(kāi)發(fā)中獲得。相互影響的自由形態(tài)曲面設(shè)計(jì)的最基本目標(biāo)是能使用戶能簡(jiǎn)單的控制曲面的形狀。一般來(lái)說(shuō)，這個(gè)目標(biāo)的追尋已經(jīng)由一種尋找“正確”的曲面描述所構(gòu)成，對(duì)于用戶來(lái)說(shuō)，他們的自由程度是足以控制指揮操作的。處理曲面造型的要素，是用控制操作B型活動(dòng)曲線規(guī)的嚙合或其他曲面制作的張力，清楚得地反映這種看法。這種控制嚙合處理出現(xiàn)在大型的測(cè)量上，因?yàn)榍婵刂泣c(diǎn)轉(zhuǎn)移的響應(yīng)是直觀的：拉或推一個(gè)控制點(diǎn)會(huì)造成那些本來(lái)能輕易地通過(guò)良好的相互影響位置的確定來(lái)控制的形狀，發(fā)生一個(gè)局部撞擊或凹陷。不幸的是，那些局部撞擊或凹陷不會(huì)只對(duì)想創(chuàng)作的人起重要作用。舉例來(lái)說(shuō)，盡管幾乎任何用控制嚙合面方法的人都有試著去做一個(gè)概念化的簡(jiǎn)單變化的失敗經(jīng)驗(yàn)，但是最后他們強(qiáng)迫去精確地復(fù)位許多甚至是全部圖形，通過(guò)控制點(diǎn)去實(shí)現(xiàn)所希望的外形。這種我們將在紙上描述的工作表明了一個(gè)通過(guò)切斷控制與描述之間聯(lián)系來(lái)避開(kāi)不可彎曲性的能力。我們想象著提供給用戶的造型是一塊無(wú)限的柔性片狀光滑曲面它本身沒(méi)有固定的控制或構(gòu)造，按它的復(fù)雜性和能力性決定細(xì)節(jié)方面也沒(méi)有前端限制。對(duì)這塊曲面來(lái)說(shuō)，用戶也許能很自由地附加一種特征變化，就像那些為了處理知道相互影響的曲面操作而年切斷的點(diǎn)和彎曲曲線。附錄 外文文獻(xiàn)Variational Surface modelingWe present a new approach to interactive modeling of freefrom surfaces. Instead of a fixed mesh of control points, the model presented to the user is that of an infinitely malleable surface, with no fixed controls. The user is free to apply control points and curves which are then available as handles for direct manipulation. The plexity of the surface’s shape may be increased by adding more control points and curves, without apparent limit. Within the constraints imposed by the controls, the shape of the surface is fully determined by one or more simple criteria, such as smoothness. Our method for solving the resulting constrained variational optimization problem rests on surface representation scheme allowing nonuniform subdivision of Bspline surfaces. Automatic subdivision is used to ensure that constraints are met, and to enforce error bounds. Efficient numerical solutions are obtained by exploiting linearities in the problem formulation and the representation. The most basic goal for interactive freeform surface design is to make it easy for the user to control the shape of the surface. Traditionally, the pursuit of this goal has taken the form of a search for the “right” surface representation, one whose degrees of freedom suffice as controls for direct manipulation by the user. The dominant approach to surface modeling, using a control mesh to manipulate a Bspline or other tensor product surface, clearly reflects this outlook.The control mesh approach is appealing in large measure because the surface’s response to control point displacements is intuitive: pulling or pushing a control point makes a local bump or dent whose shape is quite easily controlled by fine interactive positioning. Unfortunately, local bumps and dents are not the only features one wants to create. For example, almost anyone who has used a control mesh interface has had the frustrating experience of trying to make a conceptually simple change, but being forced in the end to precisely reposition many—even all—the control points to achieve the desired effect.The work we will describe in this paper represents an effort to escape this kind of inflexibility by severing the tie between the controls and the representation. The model we envision presenting to the user is that of an infinitely malleable piecewise smooth surface, with no fixed controls or structure of its own, and with no prior limit on its plexity or ability to resolve detail. To this surface, the user may freely attach a variety of features, such as points and flexible curves, which then serve as handles for direct interactive manipulation of
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