汽车工程专业外文翻译--传统车身与现代车身设计方法

1、.外文原文Traditional car body and modern car body design method1、Traditional car body design methodThe autocar car body shape is one of the three greatest fractions that are paralleled with bedrock and engine in the autocar structure, its development and capacity preparation cycle is the longest, and th

2、e preparation work of chart paper and craft is the biggest, and it is usually still need to remodel, unlike bedrock and engine attain which is easy to reach serialization and generalization.The characteristics of car body structure lies on the constitution of car body shape of each null parties be b

3、ig for size more but shape complicated space curved face(namely so-called person type overlay piece), these space curved faces can not be used ordinary machinery drawing method will it the complete earths surface appear, as a result have to create stereoscopic pattern as basis. For making these char

4、t paper and change a type tangibly express shape and structure of car body, need to pass a complicated design process to complete.In the traditional car body design, the design information and the data of car body deliver mainly by two-dimensional chart paper and principal mode type, there are many

5、design fraction of persons hand work. The defects that traditional design method can not overcome embody at as follows a few aspects:1、The manpower resource consume greatly. The traditional car body designs a tapping requirement the art designing personnel, engineering the technical personnel and it

6、s operative make a concerted effort, such as the creation and conservancy, molding tool of the two-dimensional engineering chart (the plot of car body graph), soil pattern design, production, grind to go together with and adjust to try, capacity prepare medium process planning etc.s will expend a pe

7、rson quantitative manpower and resource.2、Designing accuracy is low, the cycle is long. Accuracy low and main reasons lying in the information of each link that designs with born reserve to deliver is a kind of “move a shape, For example from lord draftion board manufacture principal mode Xing, is c

8、arried on by the principal mode type to process craft supplement, production craft pattern, from convex of the craft pattern turn over into concave craft pattern, again is depended by the craft pattern anti to process trimming die, after the convert of these links, raw datas the error of various fac

9、titiousness unavoidable, cause the molding tool accuracy of processings canning not assure, only depend next move of the hand work grind to go together with to clinch.3、Car body already set over speedy and the incapability carry on proceed together design. Traditional car bodys designing is basicall

10、y a kind of one-way anti reversible design status, product once already set, modification or remodel very difficult, the universal turns, the series turn a degree low.In addition, the car body of the modern autocar null parts because of the requirement of structure and beauty, the space curved face

11、gradually complicates, traditional design method F very difficult satisfy design request.2、Modern car body design methodAs design and modification of autocar car body shape request gradually increasing higher requirements, the parameter designment match more and come closer to the conceptual design

12、in modern CAD and proceed together design thought, and can develop the flexibility of design and analysis, therefore the parameter of the car body craft shape design have already become a inevitable trend of vehicle production. The traditional hand work shape method has already been replaced by Comp

13、uter aided modeling method which is base on various of advanced modeling soft wares, Parametric design technology can quickly absorb the foreign autocar car body designs of advanced technique, quickly respond to a market, upgrading the capability of independence design and improving autocar product

14、competitive power in our country. Since 70s in last century, along with the increasing development of computer aided geometric design and Computer graphics, the car body designs process mid for decide or the whole distances lead into calculator supporting system (CAD/CAM software), the garbage sets

15、up car body 3D digitize pattern, with” hat you see is what you get of alternate mode the perfect design scheme is the main features of modern car body design method. The basic process is following: After investigating the market, forming a car type of whole request; Manufacture hand-drawing effect c

16、hart, also available calculator assistance the software draw; The creation shrinks ratio and principal mode type; Set up car body figure pattern by the mode garbage of three coordinates scanning or laser scanning; Carry on a structure design, set up A class pattern; Born NC code produces a kind car.

17、 Draw an effect chart step, can hand work plot also the available calculator assistance software plot, concrete according to personal condition of designer and then settle, but use calculator plot can fasterly set up a car body figure pattern and make to modify an operate more convenient. But the us

18、e hand work plot rework make to shrink scale model with 1:a , again scan by three coordinateness or the laser scan of the mode garbage set up car body figure pattern, this is inner common use kind of method, because manufacture pattern in this way can even keep the style principle that the view eart

19、hs surface reaches to a designer. This is actually a process of contrary design. In a brief, the contrary engineering is to point the product pattern conversion that will have been already had to design in the process and apply very extensively in the car body for the process of the pattern of digit

20、ize engineering design in the calculator, equal hence 1 kind make copy and have to develop a cycle short, designing the accuracy being higher and easy to progress structure designing/ analyzing waiting merit.The famous soft wares, such as CATIA, IMAGEWARE and UG etc provided the strong reversal the

21、design function. The car body figure pattern cans share after creating and is advantageous to each segment realize to proceed together an operate and thus and consumedly shorten to design a cycle, and used for various CAD/CAM systems of car body design all according to 3D solid pattern auto born two

22、-dimensional car body chart paper and used for number to control the code of transform, at the same time when the 3D pattern takes place arbitrarily minuscule transform, the systems will of oneself modify with of related chart the paper and number control a code. Use a far-ranging calculator to lend

23、 support to software currently CATIA is the most famous, it is a CAD/CAM/CAE software that is reached Suo company and IBM by France to unite tapping, and the function is extremely strong. CATIA provides to have perfect CLASSA (A class curved face, this denomination also from reach Suo to propose fir

24、st) to set up function. CLASS the A curved face is in a brief a car body shape, instrument board, inside decoration piece etc. higher to curved face quality requirements type of curved face of parts, namely and only agreeable requests higher type of curved face, since wanting a surface is smooth and

25、 links to transfer smooth satisfy aerodynamics principle with the significant decrease air resistance, and then want to reserve the beauty of shape. Here point of A class curved face optics follow the sexual notion can in brief define from mathematics for: curve two ranks are several what continuous

26、, have no redundancy to turn a dot, curvature change balance, the strain energy is smaller. Is a G2 at least sequential(curvature continuous) to curved face, also namely two curved faces follow public tie line to be placed in all directions to have common law curvature. While putting together connec

27、ting, car body shape different curved face slabs continuousness have smooth request to transfer, satisfy G2 at least, even G3 continuous. The CLASS A curved face describes with the B kind method, the nodal point vector adopts tired the long parameter applying string turn a law; In the U, curved face

28、s V direction last time count at 3-7 times of, the maximum was 9 times no bigger than. In the actual design can from as follows a few aspects to evaluate A class curved face mass: the continuity, curved face whole cooperativeness, curved face of the inner mass, curved face of the design accuracy, cu

29、rved face of curved face satisfy car body structure the design and car body make a request. Positive because garbage energy such convenience, efficiently sets up CLASS A curved face, it just lets car body solid the shape is accurate day by day and quick, design a personnel construct more Be approach

30、ed to reality, curved face mass higher car body 3D pattern. Garbage not only can vs. car body external appearance and inside decoration create figure pattern, and can vs. engine, bedrock etc. other null parts create pattern, and directly carry on a limited kyat analysis, structure design/analysis, e

31、ven conjecture assembly and virtual air opening test etc., making to design a personnel can set up virtual electron kind with the garbage car and carry on trial, can in advance discover the existent question in the design before physically producing, raised an efficiency, lowered cost. Usually each

32、kit pattern sort is depositing in a large data bank, hereafter can go direct to match in the data bank while improving vs. the car type similar of null parts, modify its related parameter then meet demand, have never needed to re- design, be advantageous to the series of car type to turn very much,

33、produce company should to quick change of the capability of the market Be also strong to get poly.3、Domestic and international search present conditionCompare bigger autocar companies to widespread adopt the two-dimensional design of CAD system progress car body in the world, like the general arrang

34、ement(person machine engineering) of car body, inside the curved face structure of the outside overlay piece design, null parts structure and assembly design, molding tool design, and automatically born related design technique document. CAM/CAE is to apply to the CIMS technique also very universal.

35、 Each big autocar manufacturing companies all own their huge car body tapping of oneself troops, and dont hesitate to throw in the laboratory that the mint capital create a forerunner, develop or usher in the technical software progress car body design.Designing applied more earth of realm in the ca

36、r body can the software mainly has the United States Auto studio of the ALIAS Company, CATIA of subsidiary Daussault of IBM Company, PRO/Engineer etc. of the UG of EDS Company, parameter Technique Company. These soft wares all belong to in general use machine design software and have stronger curved

37、 face design, parameter to turn designed capacity or mix to design function, and can favor the machinery manufacturing whole processes, then design a model engineering analysis the transform make, some even can better backing car body design of first step, namely conceptual design(Concept Design) st

38、ep(is like Auto studio), and put together with model tie through a certain way it, design plane the convert as two-dimensional pattern.The local calculator is used for an autocar design to begin from 70s.The long spring vapor grinds agreeable procedure car body exclusive use function of the curved f

39、ace optics developed board, created its car body graphics used in design library, developed the autocar car body surface shape and structure design process system, the system had to draw car body soil draftion board and car body part drawing and provide transform principal mode type NC data, manufac

40、ture the capability of soil pattern. The autocar motorcycle manufacturing company in Peking develops the BJA-BSM car body CAD system, successfully is applied to BJ124, the BJ125 waits the car type of various new car type operate. Shanghai G.M. and Shanghai together helped together Jie science and te

41、chnology limited company etc. to design to develop flow process to carry on to a little bit thoroughly study vs. the car body and forming a more perfect car body tapping procedure. But still exist a lot of problems that need settle urgently in the aspects of clicking a data handling, curved face sur

42、face optics being agreeable, mathematical models converting process waiting. Is a lot of local win a small autocar business because of the restriction of capital, equipment and personnel, can not carry on the search and application of comparing the system to the car body design method, or only apply

43、 some one realm, applied get maximum of also just make vs. the product partial or little yellow of change.中文译文传统车身与现代车身设计方法1、传统车身设计方法汽车车身外形是汽车结构中与底盘和发动机并列的三大部分之一，其开发和生产准备周期最长，图纸及工艺准备的工作量最人，并且还经常要改型，不像底盘和发动机那样容易做到系列化、通用化。车身结构的特点在于组成车身外形的各个零部件多为尺寸大而形状复杂的空间曲面(即所谓人型覆盖件)，这些空间曲面无法用一般的机械制图方法将其完整地表现出来，因而不得不

44、建立立体模型作为依据。为了使这些图纸和换型能够确切地表现出车身的形状和结构，需要通过一套复杂的设计程序来完成。在传统车身设计方法中，车身的设计信息和数据的传递主要是靠二维图纸和主模型，人的手工设计部分较多。传统设计方法无法克服的缺点土要体现在以下几个方面：1、人力物力消耗大。传统的车身设计开发需要美工人员、工程技术人员及其工人通力合作，如二维工程图(车身曲线图的绘制)、土模型的制作和保存、模具设计、制造、研配和调试、生产准备中的工艺设计等都将耗费人量的人力和物力。2、设计精度低、周期长。精度低的主要原因在于设计和生成准备的各个环节之间信息传递是一种“移形”，例如由主图板制作主模刑，由主模型进行

45、加工工艺补充，制造工艺模型，由凸的工艺模型翻成凹的工艺模型，再由工艺模型反靠加工冲模，原始数据经过这些环节的转换，各种人为的误差就在所难免，导致加工出的模具精度无法保证，只有靠下一步的手工研配来解决。3、车身定型过早且不能进行并行设计。传统车身设计基本上是一种单向不可逆设计状态，产品一旦定型，修改或改型非常困难，通用化、系列化程度低。此外，现代汽车的车身零部件由于结构和美观的需要，空间曲面日趋复杂化，传统的设计方法己很难满足设计要求。传统的车身设计方法的流程可用图1.1来表示。2、现代车身设计方法随着汽车车身造型的设计与修改要求日趋增高，参数化设计更符合和贴近现代CAD中的概念设计和并行设计思

46、想，并可提高设计与分析的柔性，因此车身模型的参数化设计已经成为车辆制造行业发展的必然趋势。目前传统的手工造型方法已被建立在各种先进的造型建模软件基础上的计算机辅助造型方法所取代，参数化设计技术能够快速吸收国外汽车车身设计的先进技术，快速响应市场，提高我国自主设计开发汽车的能力，提高汽车产品竞争能力。上世纪70年代以来，随着计算机辅助几何设计和计算机图形学的迅速发展，车身设计过程中部分或全程引入计算机辅助系统(CAD/CAM软件)，在计算机中构建车身三维数字化模型，以“所见即所得的”交互方式完善设计方案，是现代车身设计方法的主要特点。其基本流程：经过市场调研，形成车型的整体要求；制作手绘效果图，

47、也可利用计算机辅助软件绘制；制作缩比例及主模型；以三坐标扫描或激光扫描的方式在计算机中构建车身数字模型；进行结构设计，构建A级模型；生成NC代码，生产样车。在绘制效果图阶段，可手工绘制也可利用计算机辅助软件绘制，具体根据设计师个人情况而定，但使用计算机绘制可更快捷地构建车身数字模型并使修改工作更方便。而使用手工绘制再制作缩比例模型和1:1主模型，再以三坐标扫描或激光扫描的方式在计算机中构建车身数字模型，这是更常用的一种方法，因为以这种方式制作模型更能直观地表达出设计师的风格理念。这实际上就是一个逆向设计的过程。简单地说，逆向工程就是指将已有的产品模型转化为计算机中的数字化工程设计模型的过程，相当于是一种仿制，具有开发周期短、设计精度较高、便于进行结构设计/分析等优点，在车身设计过程中应用很广泛。著名的C A T I A 、IMAGEWARE、UG等软件都提供了强大的逆向设计功能。车身数字模型建立后可共享，有利于各部门实现并行工作，从而大大缩短设计周期，而且用于车身设计的各种CAD/CAM系统都能够根据三维实体模型自动生成二维的车身图纸和用于数控加工的代码，同时当三维模型发生任意微小的改变时,系统都会自动地修改与