机械专业毕业设计外文翻译--现代工程机械行业的技术进步
中英文翻译
英文原文：
Modern construction machinery industry of technical progress
Large-size mechanical mining excavator is used widely in international and domestic engineering construction and mining performance, and its property defines the efficiency much.Now because the international market is opened step step, how to promote the quality of excavator is the key that a factory reinforces its competing force.
In our country，the designing elevation and production quality on excavator can not keep up with international advanced technology applying on excavator.Now the advanced technology has already applied advanced designing method on excavator designing，such as electronic simulating theory，dynamic design，reliability design and so on.But in our country ,the most excavator design has still applied the traditional design method ,the modern design method has not began to be actually applied .The prime display is that the capability of self-design is not enough and the basic work has not done perfectly especially the excavator kinetics .
The construct of excavator is very complex and the multiple movers often work simultaneously.at the same time its working environment is very bad and the eternal load varies randomly.As a result ,when designing the new product of excavator ,in order to ensure the performance safety，the designer not only has the basic theory analysis on static load computing ,but also do necessary work about the kinetics of mechanism to qualify the dynamic reliability in the period of designing .Trough the kinetic analysis ,the load property of all the elements in excavator can be decided so as to design reliable product .
From the 1980s of the 20th century to the beginning of this century. Chinese and foreign engineering machinery technology products come from a maturity period of modernization along with a new technological revolution, Mechanical engineering products integrated technology to a new level.
Electronic technology, micro-computer, sensors, electro-hydraulic servo control system integration and transformation of the traditional mechanical engineering products, Computer-aided design and computer-aided manufacturing and computer-aided management of construction machinery and equipment manufacturing, IT network technology equipment, construction machinery sales and information transfer systems, thus enabling people to see a brand new construction machinery industry. New construction machinery products in the efficiency and operational quality, environmental protection, performance and automation are many areas due to the past. and toward the further robotic and intelligent direction.
1、operating principles of Innovation : groundbreaking new law with the high-frequency vibration
With scientific and technological research in the development, engineering machinery operating theory is constantly innovating. Operating mechanical engineering principles, including the cutting of earth, broken ground on the screen geotextile material, mixed with heating, right mixture of paving, leveling and compaction, etc.. These operations Jimmy initially bionics and Newtonian mechanics-based, Modern science and the development of engineering machinery operating principle of laying the foundation for innovation. For example, mechanical vibration and pulse jet, the photoelectric effect and thermal physics, the application of mechanical engineering to save resources and improve the quality of construction improve production efficiency, reliability and driving comfort and a degree of automation to create conditions.
Excavators, bulldozers, loaders, and other earthmoving machinery cutting groundbreaking project, we had no struggle milling, high-frequency vibration, Liquid gas jet method and porous ground breaking law. Groundbreaking use of the new operating principle of transformation to a bucket, can loosen the soil excavation for the high-intensity rock, Under normal circumstances can reduce the unit cost of earthwork and improve production efficiency, and the soil near the building when substitute
bored-blasting method.
Vibratory Roller is a mechanical vibration and have reached a "sluggish vibration to" operational effectiveness of the most powerful note. High-frequency vibration compaction technology is the application of modern dynamics in the mechanical engineering important research results, In vibratory roller simultaneously with the application of vibration isolation theory. 90s of the 20th century, there have been a level of vibration (vibration) and vertical vibration directional vibration compaction method, and an AM-vibration and different from the harmonic vibration of chaotic vibration vibratory compaction operating principle, and the formation of the corresponding series of vibratory roller. Impact Roller broke the existing traditional cylindrical roller structure, Use 3-5 edge with the pressure roller polygon dragged by a tractor, 2-3 times per second in order to impact on the ground. This has dramatic impact on the seismic wave propagation characteristics, the depth of compaction several times with the RCC and incremental, 5m in the depths of the degree of compaction of up 90%-92%. Impact Roller is static shock, vibration and rub it smashes the comprehensive role for large fill, Collapse dry sand and soil filling the compaction.
Asphalt paver Weiping equipment is operating principles of mechanical engineering innovation typical example. Fung plate diesel, liquefied petroleum gas or electric heating and 60 Hz frequency of vibration, and using infrared, ultrasonic or laser leveling, is a multidisciplinary high-tech applications. This leveling the technology can be applied to the ground plane, as amlodipine or fine leveling the slope.
Transfer frequency mechanical vibration is also commonly used for drilling, stone crushing and sieving and Shen pulling piling works. The stone drying can use diesel, fuel oil and coal combustion of various fuels on the asphalt from the barrel, heating and asphalt mixture, stirring and insulation process is the full use of thermal theory of physics. Asphalt emulsion and some are modified chemical reaction physical specific application.
2、drive innovation : universal hydraulic and electric drive
Hydraulic drive in the 20th century, the 1960s applied to the roller, only 10 years on the time has been spread and popularize. Now roller travel, vibration, steering and braking systems has achieved the full hydraulic drive. Hydraulic drive greatly simplified the roller drive and control system design, hydraulic drive a smooth, convenient manipulation effort, easy to achieve variable speed and automation, in general, improve the production efficiency of roller compaction and quality. Now foreign markets have seen very little mechanical transmission of the roller.
Hydrostatic drive technology in the 1970s began to use bulldozers, and will soon be extended to a number of small and medium bulldozers and loaders, the United States John Deere, Caterpillar, Germany Bohai benefit companies and Dole produced by Komatsu of Japan has production and sales pushed Temple hydraulic machines and loaders. Hydrostatic drive not to use hydraulic torque converter, which dispense with the left lane and brake parts and mechanical drive, use of a safety valve on mechanical and hydraulic systems overload protection, and the index of smaller power play biggest index, its remaining power available in the auxiliary machinery operation.
German company Deutsche mark and Lee Bohai Fall of other public companies in 1954 and in 1955 took the lead in developing a hydraulic excavator , but the hydrostatic transmission in large excavator is the popularization and application of the 1970s. Since the early 1980s, excavators and subdivided, is gradually realized - powered, rotary and the hydraulic excavator of. In the international market excavators, were all eliminated various mechanical drive.
Late history of the birth of the road is more mechanical hydraulic drive-based, such as paver, soil stabilizer, Pavement milling machine, hydraulic transmission smoothness help improve the quality of the roads paved. Drilling in the car and drilling machines, hydraulic transmission has replaced the previous aerodynamic, Wheeled modern cranes and machinery also piling work to the whole in the direction of hydraulic development.
Electricity in industrial production while the application has a long
history, but in mobile machinery is seldom used. This is because, firstly, to the motor capacity of, a motor with the same power as compared to the hydraulic motor, its weight and bulk to good times, to the machinery space layout brought great difficulties. In addition, the efficiency of electrical transmission over low efficiency and consumption of a large volume of non-ferrous metals. But electric drive can be well realized variable speed, braking and electrical power streaming -- Drive more convenient and easy to large tub, large excavator and large loaders, engine-generator-electric wheels will transfer power. Germany V ogele also been developed for electric power will transfer wheel. Germany V ogele also been developed electric drive an asphalt paver, the aircraft's systems are all rotary motor driven electricity, Only Hopper CDCC and comfort slab leveling tank still use hydraulic transmission. The other is the regional mobile operations in the smaller mining site, the use of electric drive large excavator loaders, Such use of electric drive power transmission cables without the engine installed on the machines.
3、ergonomic innovations : a people-oriented and simplified operation
1980s of the 20th century, Many of the world's largest engineering machinery manufacturing company has invested considerable human and financial resources for modern design methodology of the research and used. Ergonomics is a "people-oriented" design, with emphasis on the machines mutual coordination and crew safety, driving comfort, convenience in the driver's operation and maintenance technologies, such drivers both improved working conditions, and increased production efficiency, and some of the engineering machinery vibration, noise, emissions and the prevention of roller drop from the development of the new standard, and even those laws.
Now all kinds of projects are mechanical design roller defense and falling-object protective devices to protect the personal safety of the drivers, with the cab and are designed and installed. Indoor driving sufficient human space and broad vision, and to take the necessary seals, vibration, noise and temperature control measures. Indoor chairs, pieces of the stick, gauges and the monitor according to ergonomics and design and minimize the
manipulation and control of parts. To reduce driver fatigue, to choose the suspension damping chairs, and to develop a gas-liquid system hanging with the cab floor.
Electronic technology, mechanical engineering applications, which greatly simplifies the driver's operational procedures and to the machine's technical performance. The use of electronic control machine can automatically choose the mode of operation, such as excavators to the three operating modes -- boom priority, Rotary priorities and micro-adjustment tandem wheels all vibration and vibration. Electronic monitoring can detect and remove machines system failures, such as engine oil pressure loss. Fan fracture belt drive, hydraulic oil contamination or overheating and oil filter blockage, can promptly lights or audible alarm, by the use of electronic sensor device can handle automatic detection machines quality of the work, If random vibration testing of the degree of compaction roller, automatic detection and adjustment of the asphalt mixture ratio and size distribution outlet temperature.
American muffler technology company developed an electronic silencer, electronic equipment engine exhaust noise analysis of the wave structure, and produce a phase difference of 180 °with the acoustic interference, This "anti-noise" and the engine exhaust noise offset, which over the purpose of the muffler. Such a muffler -- can be used to eliminate the basic engine noise and the noise indoor driving. Muffler and isolation through the engineering machinery driving indoor noise can be reduced to 70dB (A) below.
In addition, by concentrating on lubrication, automatic lubrication and fault alarm, greatly reducing the engineering and mechanical maintenance workload. Dreiser companies axis articulated loader lubrication cycle extended to 2000h. oil and filter replacement cycle extended to 250h; Caterpillar loader routine maintenance to shorten the time 3.45min. 100 hours use of the technical maintenance for only 6-7min.
4、Creative : industrial design with the environment
Modern science and technology of high-speed development, promoting
social progress, for humanity to a high degree of material civilization and spiritual civilization. Industrial design is the product of industrial product design, product also known as the art form. Mechanical Products art forms should be able to demonstrate its function in a rational and external quality of uniformity, the product should reflect the advanced technology and meet the aesthetic requirements of modernity.
For mechanical engineering, said it was "a Paper goods sold," That is an exaggeration, but not to modeling design is certainly not desirable. Modeling the mechanical engineering design of the machine can shape their structure, function and use requirements, paying and with the psychological and physical coordination. This modeling design should include ministries of proper body fluid, color coordination, Instrumentation layout beautiful and easy to operate and intuitive sign in the trademark symbol. Now the world's major companies have attached great importance to the products of industrial design, and a specialized research and design.
A world leader left the compactor manufacturers -- BMW, his third of the mechanical compaction machine modeling experts from the industrial design Louis.L.lepoix design, have a good overall result. The series dismounting replacement filter, transmission pieces, hoses and routine maintenance is very convenient. Adopt modern arc-shaped dip in the cab and the engine hood broadminded, fluent lines, with the flavor of the times. Driving the steering wheel height and angle adjustable, choose a comfortable high back seats adjustable damping. Drivers prepare for a good operating environment. Instrumentation site design, easier to observe and control, tilt hood of the driver to provide a good perspective. Hydraulic steering gear shifted to the cab, driving to reduce indoor heat and noise. Arc-shaped windscreen of the cab and four SUPPORT able to isolate noise and vibration. indoor noise below 70d
B (A).
Many other engineering machinery are also different degrees of emphasis on industrial design, layout components such as depression, to reduce the center of gravity of the aircraft; Supporting appropriate to expand
the area to increase the machine's stability; about as symmetrical layout, to meet the aesthetic; Appearance removed some of the corner, the edge, to show the fluency, and other lines. Construction Machinery paint more of its industrial design is an important part of the unit should be interesting colors, increase the safety of the working environment, and with the field construction site is pure green fields, coordination, Topping the use of the waist line and increase the level to get off the color machines can increase the concentration of visual stability.
５、artificial intelligence Innovation : intelligent robotic machines Mechanical engineering in the construction field instead of the manual to expand the functions of the hands and feet, traditional machinery can be resolved in good physical and physiological burden, not to mention the relief of spiritual and psychological burden. Modern engineering machinery should be given its soulful, intelligent engineering machinery is a thinking mind (microcomputer) sensorium (sensors), neural network (electronic transmission). Derrnatopathy (power and transmission), and hand, foot bones (work with devices running) for telecommunications systems integration.
Machine is not electromechanical integration of telecommunications and information technology with a simple, it poses the system must have five functions : ① detection and identification with the objects of their work and working conditions of the function; ②goal with under their own decision-making function; ③have to respond to the decision-making, implementation support movement functions; ④ with automated monitoring and self-revision process functions; ⑤z own self-protection and security troubleshooting functions. This is the Intelligent Engineering Machinery some specific goals.
In mechanical engineering intelligent process, from beginning to end, filled with self-learning technology and the use of adaptive technology. Now for the integration of telecommunications technology for the engine and hydraulic system and electrical system of full control machines are being given various feelings and wisdom. In the process with the state of real-time
monitoring on the basis of mechanical engineering from the partial automation of the transition to full automation, and toward unmanned remote control and the trend of development. With the intervention of artificial intelligence, engineering machinery will accelerate its modern fast process, Gradual transition to a fully operational wisdom of the target robot. At that time, some new robotic operating procedures will come into being.
译文：
现代工程机械行业的技术进步
大型机械式挖掘机在目前国际国内在矿山开采及工程施工中有着广泛的应用，其性能的优劣对生产率有很大的影响.在国际市场竟争日趋激烈的今天，如何提高产品的质量是提高其市场竞争力的关键。
目前，我国的大型机械式挖掘机在设计水平，设计手段及产品质量上与国外同类产品相比尚有较大差距.国外已经将人一机一环境作为一个系统统一考虑，提倡低振动、低噪音的绿色设计，将现代设计方法(电子模拟理论、动态设计、可靠性设计等)普遍地应用于挖掘机设计，使产品设计现代化，性能可靠。而我国仍然主要采用传统的仿型设计，而近年来才将现代设计方法逐步应用到挖掘机的设计上，但在这方面工作开展的不得力，主要表现在自行设计开发能力不够，基础工作做得不完善，尤其在挖掘机动力学方面。
挖掘机结构非常复杂，往往是多发动机同时驱动，同时工作环境恶劣，外载荷成随机性变化，因此在设计大型矿用挖掘机的新产品时，为了使其作业安全，工作顺畅，除必要的理论分析和静强度计算外，还必须要进行动力学分析和计算，以在设计之初保证机械的动强度和可靠性。在进行这种分析时，土壤的力学特性必须考虑，而且是重要因素。通过进行动力学研究，才能确定挖掘机各部件的载荷特性，设计出质量可靠的产品。
从20世纪80年代到本世纪初，中外工程机械产品技术已从一个成熟期走到了现代化时期伴随着一场新的技术革命，工程机械产品的综合技术水平跃上了一个新的台阶。电子技术、微电脑、传感器、电液伺服与控制系统集成化改造了传统的工程机械产品，计算机辅助设计、辅助制造及辅助管理装备了工程机械制造业，IT网络技术也装备了工程机械的销售与信息传递系统，从而让人们看到了一个全新的工程机械行业。新的工程机械产品在工作效率、作业质量、环境保护、操作性能及自动化程度诸多方面都是以往所不可比拟的，并且在向着进一步的智能化和机器人化方向迈进。1、作业原理创新：新法破土与高频振动
随着科学技术研究水平的不断发展，工程机械的作业理论也在不断地创新。工程机械的作业原理包括对土石方的切割、破碎、回填，对土工材料的筛分、混合与加热，对混合料的摊铺、找平与压实等。这些作业理原先是以仿生学与牛顿力学为基础的，而近现代科学的发展为工程机械作业原理的创新奠定了基础。例如机械振动、脉冲、射流、光电效应及热物理学的应用，为工程机械节省资源，改善施工质量、提高生
产效率、工作可靠性、驾驶舒适性与自动化程度创造了条件。
挖掘机、推土机、装载机等土方工程机械切割破土，现在有了无斗铣切法、高频振动法、液气射流法及微孔破土法。使用新的破土作业原理改造的铲斗、松土器可以开挖高强度的岩土，在一般情况下都可以降低单位土方费用与提高生产效率，并且在靠近建筑物挖土时可代替钻孔—爆破法施工。
振动压路机是利用机械振动而又要达成“振地不振人”作业效果的最有力说明。高频振动压实技术的应用是近代动力学在工程机械上的重要科研成果，在振动压路机上同时应用了振动与隔振理论。20世纪90年代以来，出现了水平振动（振荡）与垂直振动的定向振动压实方法，以及无级调幅振动和不同于简谐振动的混沌振动等振动压实作业原理，并且形成了相应系列的振动压路机。冲击式压路机打破了原有传统的圆柱形滚轮结构，使用具有3-5个边的多边形压滚由牵引车拖行，以每秒2-3次顺序地冲击地面。这种剧烈冲击具有地震波的传播特性，其压实深度随碾压遍数而递增，在5m深处的压实度可达90%-92%。冲击压路机具有静压冲击、振动捣实与揉搓的综合作用，适合大型填方、塌陷土壤和干砂填筑工程的压实。
沥青混凝土摊铺机慰平工作装置更是工程机械作业原理创新的典型例子。慰平板使用柴油、液化气或电加热和72Hz的调频振动，并采用红外线、激光或超声波找平，是多学科高新技术的应用。这其中的找平技术也可以应用到平地机上，作为地平或坡面的精细找平。
调频率机械振动还通常用于凿岩、石料破碎与筛分及沉拔桩等工程施工。石料的烘干可以使用柴油、重油和煤粉多种燃料的燃烧器，沥青的脱桶、加热及沥青混合料的搅拌与保温过程中都充分运用了热物理学原理。沥青的乳化与改性都是一些化学物理反应的具体应用。
2、传动方式创新：普及液压与电气传动
液压传动在20世纪60年代开始应用到了压路机上，只十多年的时间就得到了推广和普及。现在压路机的行走、振动、转向及制动等系统已实现了全液压传动。液压传动大大简化了压路机传动与操纵系统的设计，液压传动平稳、操纵方便省力、容易实现无级调速和自动控制、从总体上提高了压路机的生产效率与压实质量。现在国外市场上已经很少见到机械传动的压路机了。
静液压传动技术于70年代开始应用到了推土机上，并且很快推广到了一些中小型推土机和装载机上，美国约翰·迪尔公司、卡特彼勒公司、德国利渤海尔公司及日本小松制作所都生产和销售全液压推寺机与装载机。静液压传动不使用液力变矩器，
还省去了离且器与行车制动器及部分机械传动机构，能利用安全阀对机械和液压系统实现过载保护，并以较小的索引功率发挥最大的索引力，其剩余的功率可用在机器的辅助操作上。
德国的德马克公司和利渤海尔公司公别于1954年和1955年率先开发了全液压挖掘机，但静液压传动在挖掘机上大量的推广应用也是在70年代。自80年代初以来，挖掘机从大到小正逐步实现了驱动行走、回转与挖掘机的全液压化。在国际市场上的挖掘机，已全部淘汰了各种机械传动机构。
诞生历史比较晚的路面机械更是以全液压传动为主，如摊铺机、稳定土拌和机、路面铣刨机等，液压传动的平稳性有助于提高路面的铺筑质量。在凿岩台车和凿岩机上，液压传动已取代了以往的气动，现代轮式起重机和桩工机械也工向全液压化的方向发展。
电力在工业生产中的应用虽然已有很长的历史了，但在移动式机械上使用尚不多见。这首先是因为电动机的能容量小，一台电动机与同功率的液压马达相比，其重量和体积要大好多倍，这给机器的空间布置带来了很大困难。另外，电气传动的效率比效低，而消耗有色金属量大。但电气传动能很好地实现无级调速、电气制动和功率分流，电传动更方便和易于大型矿车、大型挖掘机和大型装载机上，以发动机—发电机—电动车轮传递行驶动力。德国福格勒公司还试制了电动车轮传递行驶动力。德国福格勒公司还试制了电传动的沥青摊铺机，该机的所有回转系统都用电马达带动，只有料斗开合与慰平板找平油缸仍使用液压传动。另外就是在作业区域移动较小的采矿工地上，使用了电力拖动的大型挖掘机的装载机，这种电力拖动使用电缆传输动力而不必在机器上安装发动机。
3、人机工程创新：以人为本与简化操作
20世纪80年代以来，世界上许多大的工程机械制造公司都投入很大的人力和资金促进现代设计方法学的研究和应用。人机工程学是“以人为本”的设计思想，注重机器与人的相互协调，提高人机安全性、驾驶舒适性，方便于司机操作和技术保养，这样既改善了司机的工作条件，又提高了生产效率，有的国家对工程机械的振动、噪声、废气排放和防翻滚与落物制定了新的标准，甚至付诸法律。现在各类工程机械都是设计有防翻滚和落物保护装置，以保护司机的人身安全，并且都是与驾驶室分别设计和安装。驾驶室内有足够的人体空间和开阔的视野，并采取必要的密封、减振、降噪和控温措施。室内的座椅、操纵杆件、仪表与监视器都按人机工程学布置，并且尽量减少操纵部位与操纵力。为了减轻司机的疲劳，选用悬浮式减振座椅，并研制了气
—液悬持系统的驾驶室底板。
电子技术在工程机械上的应用，大大简化了司机的操作程序和提高了机器的技术性能。利用电子控制可以自动选择机器的作业模式，例如挖掘机的3种作业模式——动臂优先、回转优先和微调整，串联振动和双轮全振动等。利用电子监测可以及时发现和排除机器系统的故障，例如发动机润滑油失压、风扇传动带断裂、液压油污染或过热和滤油器堵塞等，均能及时发出声响或灯光报警，利用电子传感器经微电脑处理可以自动检测机器的工作质量，如随机检测振动压路机的压实度，自动检测与调整沥青混合料的级配比例与出料温度等。
美国消音技术公司研制了一种电子消音器，通过电子仪器分析发动机排气噪声的波形结构，并产生一种与之相位差180°的干扰声波，这种“抗噪声”与发动机排气的噪声相抵消，从而过到消声的目的。这种电了消音器还可用于消除发动机的基本噪声和驾驶室内的噪声。通过消音和隔离的工程机械驾驶室内噪声可以降低到70dB（A）以下。
另外，通过集中润滑、自动润滑及故障自动报警，大大减少了工程机械的维修工作量。德莱赛公司装载机铰接轴的润滑周期可延长到2000h，更换机油和滤清器的周期延长到250h；卡特彼勒公司装载机的日常检修时间缩短到3.45min，使用100h的技术保养时间也仅有6-7min。
4、外观造型创新：工业设计与环境协调
现代科学技术的高速发展，推动着社会的进步，给人类带来了高度的物质文明与精神文明。工业设计即是工业产品的造型设计，也称其为产品的艺术造型。机械产品的艺术造型应能体现其功能的合理性及外在质量的统一性，还应体现出产品的技术先进性和符合时代感的审美要求。
对于工程机械，有人说“货卖一张皮”那是言过其实，但不重视造型设计肯定是不可取的。工程机械的造型设计可以使机器的形态与其结构、功能及使用要求相统一，并与人的生理及心理相协调。这种造型设计应包括各部的比例得当，形体流畅、色彩协调、仪表布置美观以及便于直观操作和有醒目的商标符号。现在世界各大公司都非常重视产品的工业设计，并且出现了专门的研究和设计机构。
居世界领先地位的压实机左制造商——宝马公司，其第三化压实机械的机器造型由工业设计专家Louis.L.lepoix设计，产生了良好的综合效果。该系列拆装更换滤清器、传动件、软管及日常保养都是很方便。采用圆弧形的现代驾驶室和在倾角的发动机罩视野开阔、线条流畅，具有时代气息。驾驶方向盘的高度与倾角可调，选用舒
适的高靠背可调减振座椅，给驾驶员准备了良好的操作环境。仪器仪表盘设计合理，易于观察和控制，发动机罩的倾斜给驾驶员提供了良好的视角。液压转向器转移到了驾驶室外，以减少驾驶室内的发热与噪声。圆弧形的挡风玻璃和驾驶室的四个外支承可隔离噪声与振动，使室内的噪声低于70dB(A)。
其它的许多工程机械也都是不同程度地注重了工业设计，例如零部件布置尽量下移，以降低整机重心；适当地扩大支承面积，以增加机器的稳定度；左右布置尽量对称，以符合人的美感；去掉一些外观造型的尖角、棱边，以显示线条的流畅等。工程机械的油漆更是其工业设计的重要内容，整机的色调应能引人注意，增加作业环境的安全，并与野外施工现场的绿树田野相映衬、协调，使用套色的水平腰线和增加下车的色彩浓度可以增加机器的视觉稳定性等。
５、人工智能创新：灵性机器与机器人化
工程机械在工程建设领域代替了人的体力劳动，扩展了人的手脚功能，但传统机械还未能解决好人的体力和生理负担问题，更不要说解脱人的精神和心理负担了。现代化工程机械应该是赋予了其灵性，有灵性的工程机械是有思维头脑（微电脑）、感觉器官（传感器）、神经网络（电子传输）、五脏六腑（动力与传动）及手足骨骼（工作机构与行走装置）的机电信一体化系统。
机电信一体化并非机电与信息技术的简单结合，它所构成的系统必须具备5项功能：①具有检测和识别工作对象与工作条件的功能；②具有根据工作目标自行作出决策的功能；③具有响应决策、执行支动作的功能；④具有自动监测工作过程与自我修正的功能；⑤具有自z身安全保护和故障排除功能。这也就是工程机械智能化的一些具体目标。
在工程机械的智能化过程中，自始至终充满着自学习技术和自适应技术的运用。现在机电信一体化技术实现了对发动机、液压系统和电气系统的全面控制，机器正在被赋予各种感觉与智慧。在工艺过程与工作状态实时监测的基础上，工程机械将从局部自动化过渡到全面自动化，并且向着远距离操纵和无人驾驶的趋势发展。随着人工智能的介入，工程机械将加快快其现代进程，使逐步过渡到完全智慧化的作业机器人目标。到那时，一些新的机器人化作业程序就会应运而生。
毕业设计外文翻译资料
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机械专业毕业论文外文翻译
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毕业论文外文翻译模版
吉林化工学院理学院 毕业论文外文翻译English Title（Times New Roman ，三号） 学生学号：08810219 学生姓名：袁庚文 专业班级：信息与计算科学0802 指导教师：赵瑛 职称副教授 起止日期：2012.2.27～2012.3.14 吉林化工学院 Jilin Institute of Chemical Technology
1 外文翻译的基本内容 应选择与本课题密切相关的外文文献（学术期刊网上的），译成中文，与原文装订在一起并独立成册。在毕业答辩前，同论文一起上交。译文字数不应少于3000个汉字。 2 书写规范 2.1 外文翻译的正文格式 正文版心设置为：上边距：3.5厘米，下边距：2.5厘米，左边距：3.5厘米，右边距：2厘米，页眉：2.5厘米，页脚：2厘米。 中文部分正文选用模板中的样式所定义的“正文”，每段落首行缩进2字；或者手动设置成每段落首行缩进2字，字体：宋体，字号：小四，行距：多倍行距1.3，间距：前段、后段均为0行。 这部分工作模板中已经自动设置为缺省值。 2.2标题格式 特别注意：各级标题的具体形式可参照外文原文确定。 1．第一级标题（如：第1章绪论）选用模板中的样式所定义的“标题1”，居左；或者手动设置成字体：黑体，居左，字号：三号，1.5倍行距，段后11磅，段前为11磅。 2．第二级标题（如：1.2 摘要与关键词）选用模板中的样式所定义的“标题2”，居左；或者手动设置成字体：黑体，居左，字号：四号，1.5倍行距，段后为0，段前0.5行。 3．第三级标题（如：1.2.1 摘要）选用模板中的样式所定义的“标题3”，居左；或者手动设置成字体：黑体，居左，字号：小四，1.5倍行距，段后为0，段前0.5行。 标题和后面文字之间空一格（半角）。 3 图表及公式等的格式说明 图表、公式、参考文献等的格式详见《吉林化工学院本科学生毕业设计说明书（论文）撰写规范及标准模版》中相关的说明。
软件开发概念和设计方法大学毕业论文外文文献翻译及原文
毕业设计（论文）外文文献翻译 文献、资料中文题目：软件开发概念和设计方法文献、资料英文题目： 文献、资料来源： 文献、资料发表（出版）日期： 院（部）： 专业： 班级： 姓名： 学号： 指导教师： 翻译日期： 2017.02.14
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机械设计理论 机械设计是一门通过设计新产品或者改进老产品来满足人类需求的应用技术科学。它涉及工程技术的各个领域，主要研究产品的尺寸、形状和详细结构的基本构思，还要研究产品在制造、销售和使用等方面的问题。 进行各种机械设计工作的人员通常被称为设计人员或者机械设计工程师。机械设计是一项创造性的工作。设计工程师不仅在工作上要有创造性，还必须在机械制图、运动学、工程材料、材料力学和机械制造工艺学等方面具有深厚的基础知识。如前所诉，机械设计的目的是生产能够满足人类需求的产品。发明、发现和科技知识本身并不一定能给人类带来好处，只有当它们被应用在产品上才能产生效益。因而，应该认识到在一个特定的产品进行设计之前，必须先确定人们是否需要这种产品。 应当把机械设计看成是机械设计人员运用创造性的才能进行产品设计、系统分析和制定产品的制造工艺学的一个良机。掌握工程基础知识要比熟记一些数据和公式更为重要。仅仅使用数据和公式是不足以在一个好的设计中做出所需的全部决定的。另一方面，应该认真精确的进行所有运算。例如，即使将一个小数点的位置放错，也会使正确的设计变成错误的。 一个好的设计人员应该勇于提出新的想法，而且愿意承担一定的风险，当新的方法不适用时，就使用原来的方法。因此，设计人员必须要有耐心，因为所花费的时间和努力并不能保证带来成功。一个全新的设计，要求屏弃许多陈旧的，为人们所熟知的方法。由于许多人墨守成规，这样做并不是一件容易的事。一位机械设计师应该不断地探索改进现有的产品的方法，在此过程中应该认真选择原有的、经过验证的设计原理，将其与未经过验证的新观念结合起来。 新设计本身会有许多缺陷和未能预料的问题发生，只有当这些缺陷和问题被解决之后，才能体现出新产品的优越性。因此，一个性能优越的产品诞生的同时，也伴随着较高的风险。应该强调的是，如果设计本身不要求采用全新的方法，就没有必要仅仅为了变革的目的而采用新方法。 在设计的初始阶段，应该允许设计人员充分发挥创造性，不受各种约束。即使产生了许多不切实际的想法，也会在设计的早期，即绘制图纸之前被改正掉。只有这样，才不致于堵塞创新的思路。通常，要提出几套设计方案，然后加以比较。很有可能在最后选定的方案中，采用了某些未被接受的方案中的一些想法。
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本科毕业论文(设计) 外文翻译 学院：机电工程学院 专业：机械工程及自动化 姓名：高峰 指导教师：李延胜 2011年05 月10日 教育部办公厅 Failure Analysis，Dimensional Determination And
Analysis，Applications Of Cams INTRODUCTION It is absolutely essential that a design engineer know how and why parts fail so that reliable machines that require minimum maintenance can be designed．Sometimes a failure can be serious，such as when a tire blows out on an automobile traveling at high speed．On the other hand，a failure may be no more than a nuisance．An example is the loosening of the radiator hose in an automobile cooling system．The consequence of this latter failure is usually the loss of some radiator coolant，a condition that is readily detected and corrected．The type of load a part absorbs is just as significant as the magnitude．Generally speaking，dynamic loads with direction reversals cause greater difficulty than static loads，and therefore，fatigue strength must be considered．Another concern is whether the material is ductile or brittle．For example，brittle materials are considered to be unacceptable where fatigue is involved． Many people mistakingly interpret the word failure to mean the actual breakage of a part．However，a design engineer must consider a broader understanding of what appreciable deformation occurs．A ductile material，however will deform a large amount prior to rupture．Excessive deformation，without fracture，may cause a machine to fail because the deformed part interferes with a moving second part．Therefore，a part fails(even if it has not physically broken)whenever it no longer fulfills its required function．Sometimes failure may be due to abnormal friction or vibration between two mating parts．Failure also may be due to a phenomenon called creep，which is the plastic flow of a material under load at elevated temperatures．In addition，the actual shape of a part may be responsible for failure．For example，stress concentrations due to sudden changes in contour must be taken into account．Evaluation of stress considerations is especially important when there are dynamic loads with direction reversals and the material is not very ductile． In general，the design engineer must consider all possible modes of failure，which include the following． ——Stress ——Deformation ——Wear ——Corrosion ——Vibration ——Environmental damage ——Loosening of fastening devices
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外文资料名称： Design and performance evaluation of vacuum cleaners using cyclone technology 外文资料出处：Korean J. Chem. Eng., 23(6), (用外文写) 925-930 (2006) 附件： 1.外文资料翻译译文 2.外文原文
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大学毕业论文---软件专业外文文献中英文翻译
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沈阳工业大学工程学院 毕业设计（论文）外文翻译 毕业设计（论文）题目：工具盒盖注塑模具设计 外文题目：Friction , Lubrication of Bearing 译文题目：轴承的摩擦与润滑 系（部）：机械系 专业班级：机械设计制造及其自动化0801 学生姓名：王宝帅 指导教师：魏晓波 2010年10 月15 日
外文文献原文： Friction , Lubrication of Bearing In many of the problem thus far , the student has been asked to disregard or neglect friction . Actually , friction is present to some degree whenever two parts are in contact and move on each other. The term friction refers to the resistance of two or more parts to movement. Friction is harmful or valuable depending upon where it occurs. friction is necessary for fastening devices such as screws and rivets which depend upon friction to hold the fastener and the parts together. Belt drivers, brakes, and tires are additional applications where friction is necessary. The friction of moving parts in a machine is harmful because it reduces the mechanical advantage of the device. The heat produced by friction is lost energy because no work takes place. Also , greater power is required to overcome the increased friction. Heat is destructive in that it causes expansion. Expansion may cause a bearing or sliding surface to fit tighter. If a great enough pressure builds up because made from low temperature materials may melt. There are three types of friction which must be overcome in moving parts: (1)starting, (2)sliding, and(3)rolling. Starting friction is the friction between two solids that tend to resist movement. When two parts are at a state of rest, the surface irregularities of both parts tend to interlock and form a wedging action. To produce motion in these parts, the wedge-shaped peaks and valleys of the stationary surfaces must be made to slide out and over each other. The rougher the two surfaces, the greater is starting friction resulting from their movement . Since there is usually no fixed pattern between the peaks and valleys of two mating parts, the irregularities do not interlock once the parts are in motion but slide over each other. The friction of the two surfaces is known as sliding friction. As shown in figure ,starting friction is always greater than sliding friction . Rolling friction occurs when roller devces are subjected to tremendous stress which cause the parts to change shape or deform. Under these conditions, the material in front of a roller tends to pile up and forces the object to roll slightly uphill. This changing of shape , known as deformation, causes a movement of molecules. As a result ,heat is produced from the added energy required to keep the parts turning and overcome friction. The friction caused by the wedging action of surface irregularities can be overcome