机械手机械设计论文中英文资料对照外文翻译

机械手机械设计论文中英文资料对照外文翻译
机械手机械设计论文中英文资料对照外文翻译

中英文资料对照外文翻译

机械设计

摘要:

机器由机械和其他元件组成的用来转换和传输能量的装置。比如:发动机、涡轮机、车、起重机、印刷机、洗衣机和摄影机。许多机械方面设计的原则和方法也同样适用于非机械方面。术语中的“构造设计”的含义比“机械设计”更加广泛,构造设计包括机械设计。在进行运动分析和结构设计时要把产品的维护和外形也考虑在机械设计中。在机械工程领域中,以及其它工程领域,都需要机械设备,比如:开关、凸轮、阀门、船舶以及搅拌机等。

关键词:设计流程设计规则机械设计

设计流程

设计开始之前就要想到机器的实用性,现有的机器需要在耐用性、效率、重量、速度,或者成本上得到改善。新的机器必需能够完全或部分代替以前人的功能,比如计算、装配、维修。

在设计的初级阶段,应该充分发挥设计人员的创意,不要受到任何约束。即使有一些不切实际的想法,也可以在设计的早期,即在绘制图纸之前被改正掉。只有这样,才不致于阻断创新的思路。通常,必须提出几套设计方案,然后进行比较。很有可能在这个计划最后指定使用某些不在计划方案内的一些想法的计划。

一般当产品的外型和组件的尺寸特点已经显现出来的时候,就可以进行全面的设计和分析。接着还要客观的分析机器性能、安全、重量、耐用性,并且成本也要考虑在内。每一个至关重要的部分要优化它的比例和尺寸,同时也要保持与其它组成部分的平衡。

选择原材料和工艺的方法。通过力学原理来分析和实现这些重要的特性,如稳定和反应的能量和摩擦力的利用,动力惯性、加速度、能量;包括材料的弹性强度、应力和刚度等物理特性,以及流体的润滑和驱动器的流体力学。设计的过程是一个反复与合作的过程,无论是正式的还是非正式的,对设计者来说每个阶段都很重要。。产品设计需要大量的研究和提升。许多的想法,必须通过努力去研究成为一种理念,然后去使用或放弃。

虽然每个工程的问题都是不同的,但设计者遵循同样的步骤去解决他们。

产品的责任诉讼迫使设计人员和公司在选择材料时,采用最好的方法。在这个过程中,最普遍的五个问题为:(a)不了解或者不使用材料应用方面最好的信息资料;(b)未能预见和考虑材料的合理用途(如可能的话,设计师应进一步预测和考虑因不当使用的产品所造成的后果。在近年来的许多产品责任诉讼案件中,由于错误地使用产品而受到伤害的原告控告生产厂家,并且赢得判决);(c)所使用的材料的数据不全或是有些数据不确定,尤其是当其性能数据长期不更新;(d)质量控制方法不适当和未经验证;(e)由一些完全不称职的人员选择材料。

通过对这五个问题的分析,可以得出这些问题没有充足的存在的理由。对这些问题的研究分析可以为避免此类问题指明方向。尽管采用最好的材料选择方法也不能避免发生产品责任诉讼,设计人员和工业界按照适当的程序进行材料选择,可以大大减少诉讼的数量。

从以上的讨论可以看出,选择材料的人应该对材料的性质,特点和加工工艺有一个全面而基本的了解。

最后,一个基于功能的设计产品和工程样机会制造出来。如果其测试效果令人满意,那么就会按照初步设计以较低的成本进行批量生产。在随后几年的生产和售后服务中,设计可能要在原有基础上进行新的构思,或者在试验和经验为基础上,进一步分析并改进,以提高产品的市场生存能力。

设计规则

在这一部分,我们要运用创造性的思维来改进和完善。也许会创造出功能更多、更经济、更耐用的产品。

为了激发创造性思维,特提出下列设计和分析的规则。前六个规则对设计者来说特别适用。

1.要有创造性的利用所需要的物理性质和控制过程。

2.认识负载产生的影响及其意义。

3.预测没有想到的负载。

4.创造出更为有利的条件。

5.提供良好的应力分布和最小的重量。

6.运用最基本的方程来优化比例和尺寸。

7.选择合成材料。

8.仔细选择所需的材料和组件。

9.调整功能的设计方案,以适应生产过程并降低成本。

10.提供准确的位置为组件安装时不干涉。

机械设计包括以下内容:

1.对设计过程、设计所需要公式以及安全系数进行介绍。

2.综述了材料的性质、静态和动态载荷分析,包括梁、振动和冲击载荷。

3.综述了应力的基本规律和失效分析。

4.介绍静态失效理论和静态载荷下机械断裂分析。

5.介绍疲劳失效理论并强调在压力条件下接近高循环的疲劳设计,这通常用在旋转机械的设计中。

6.深入探讨机械磨损机理、表面接触应力和表面疲劳现象。

7.使用疲劳分析技术校核轴的设计。

8.讨论润滑油膜与滚动轴承的理论和应用。

9.深入介绍直齿圆柱齿轮的动力学、设计和应力分析,并简单介绍斜齿轮、锥齿轮和涡轮有关方面的问题。

10.讨论弹簧设计、螺杆等紧固件的设计,包括传动螺杆和预紧固件。

11.介绍盘式和鼓式离合器以及制动器的设计和技术说明。

机械设计

完整的机械设计是一个复杂的过程。这是一项创造性的工作。项目工程师不仅要有创造性,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。

设计的第一步就是选择产品每个部分的构成材料。许多的材料被今天的设计师所使

用是因为这对产品的功能,外观、成本、制造的成本十分重要的。因此对材料的特性必须作出仔细的评估。

仔细精确的计算是必要的,以确保设计的有效性。在任何失败的情况下,最好知道在最初设计中有有缺陷的部件。计算(图纸尺寸)检查是非常重要的。一个小数点的位置放错,就可以导致一个本可以完成的项目失败。设计工作的各个方面都应该检查和复查。

计算机是一种工具,它能够帮助设计师减轻繁琐的计算,并对现有数据提供进一步的分析。交互系统是基于计算机的能力,已经使计算机辅助设计(CAD)和计算机辅助制造(CAM)成为了可能。应用专家经常谈论如何使人们适应机器。设计人员的基本职责是努力使机器来适应人们。这并不是一项容易的工作,因为实际上并不存在着一个对所有人来说都是最优的操作范围和操作过程。另一个重要问题,设计师必须能够同其他有关人员进行交流和沟通。在设计初级阶段,设计人员必须就初步设计同管理人员进行交流和沟通,并达成共识。这一般是通过口头讨论,草图和文字材料进行的。

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、发现和技术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。 ----本文译自谷歌学术

Mechanical Design

Abstract:

A machine is a combination of mechanisms and other components which transforms, transmits. Examples are engines, turbines, vehicles, hoists, printing presses, washing machines, and movie cameras. Many of the principles and methods of design that apply to machines also apply to manufactured articles that are not true machines. The term "mechanical design" is used in a broader sense than "machine design" to include their design. the motion and structural aspects and the provisions for retention and enclosure are considerations in mechanical design. Applications occur in the field of mechanical engineering, and in other engineering fields as well, all of which require mechanical devices, such as switches, cams, valves, vessels, and mixers.

Keywords: Mechanical Design mechanisms Design Process

The Design Process

Designing starts with a need real.Existing apparatus may need improvements in durability, efficiency, weight, speed, or cost. New apparatus may be needed to perform a function previously

done by men, such as computation, assembly, or servicing. With the objective wholly or partly In the design preliminary stage, should allow to design the personnel fully to display the creativity, not each kind of restraint. Even if has had many impractical ideas, also can in the design early time, namely in front of the plan blueprint is corrected. Only then, only then does not send to stops up the innovation the mentality. Usually, must propose several sets of design proposals, then perform the comparison. Has the possibility very much in the plan which finally designated, has used certain not in plan some ideas which accepts.

When the general shape and a few dimensions of the several components become apparent, analysis can begin in earnest. The analysis will have as its objective satisfactory or superior performance, plus safety and durability with minimum weight, and a competitive cost.

Optimum proportions and dimensions will be sought for each critically loaded section, together with a balance between the strengths of the several components. Materials and their treatment will be chosen. These important objectives can be attained only by analysis based upon the principles of mechanics, such as those of static for reaction forces and for the optimum utilization of friction; of dynamics for inertia, acceleration, and energy; of elasticity and strength of materials for stress and deflection; of physical behavior of materials; and of fluid mechanics for lubrication and hydrodynamic drives. The analyses may be made by the same engineer who conceived the arrangement of mechanisms, or, in a large company, they may be made by a separate analysis division or research group. Design is a reiterative and cooperative process, whether done formally or informally, and the analyst can contribute to phases other than his own. Product design requires much research and development. Many Concepts of an idea must be studied, tried, and then either used or discarded. Although the content of each engineering problem is unique, the designers follow the similar process to solve the problems.

Product liability suits designers and forced in material selection, using the best program. In the process of material, the most common problems for five (a) don't understand or not use about the latest application materials to the best information, (b) failed to foresee and consider the reasonable use material may (such as possible, designers should further forecast and consider due to improper use products. In recent years, many products liability in litigation, the use of products and hurt the plaintiff accused manufacturer, and won the decision), (c) of the materials used all or some of the data, data, especially when the uncertainty long-term performance data is so, (d) quality control method is not suitable and unproven, (e) by some completely incompetent persons choose materials.

Through to the above five questions analysis, may obtain these questions is does not have the sufficient reason existence the conclusion. May for avoid these questions to these questions research analyses the appearance indicating the direction. Although uses the best choice of material method not to be able to avoid having the product responsibility lawsuit, designs the personnel and the industry carries on the choice of material according to the suitable procedure, may greatly reduce the lawsuit the quantity.

May see from the above discussion, the choice material people should to the material nature, the characteristic and the processing method have comprehensive and the basic understanding.

Finally, a design based upon function, and a prototype may be built. If its tests are satisfactory, the initial design will undergo certain modifications that enable it to be

manufactured in quantity at a lower cost. During subsequent years of manufacture and service, the design is likely to undergo changes as new ideas are conceived or as further analyses based upon tests and experience indicate alterations. Sales appeal.

Some Rules for Design

In this section it is suggested that, applied with a creative attitude, analyses can lead to important improvements and to the conception and perfection of alternate, perhaps more functional, economical,

and durable products.

To stimulate creative thought, the following rules are suggested for the designer and analyst. The first six rules are particularly applicable for the analyst.

1. A creative use of need of physical properties and control process.

2. Recognize functional loads and their significance.

3. Anticipate unintentional loads.

4. Devise more favorable loading conditions.

5. Provide for favorable stress distribution and stiffness with minimum weight.

6. Use basic equations to proportion and optimize dimensions.

7. Choose materials for a combination of properties.

8. Select carefully, stock and integral components.

9. Modify a functional design to fit the manufacturing process and reduce cost.

10. Provide for accurate location and noninterference of parts in assembly.

Machinery design covers the following contents.

1. Provides an introduction to the design process , problem formulation ,safety factors.

2. Reviews the material properties and static and dynamic loading analysis ,

Including beam , vibration and impact loading.

3. Reviews the fundamentals of stress and defection analysis.

4. Introduces fatigue-failure theory with the emphasis on stress-life approaches to

high-cycle fatigue design, which is commonly used in the design of rotation machinery.

5. Discusses thoroughly the phenomena of wear mechanisms, surface contact stresses ,and surface fatigue.

6. Investigates shaft design using the fatigue-analysis techniques.

7. Discusses fluid-film and rolling-element bearing theory and application

8. Gives a thorough introduction to the kinematics, design and stress analysis of spur gears , and a simple introduction to helical ,bevel ,and worm gearing.

9. Discusses spring design including compression ,extension and torsion springs.

10. Deals with screws and fasteners including power screw and preload fasteners.

11. Introduces the design and specification of disk and drum clutches and brakes. Machine Design

The complete design of a machine is a complex process. The machine design is a creative work. Project engineer not only must have the creativity in the work, but also must in aspect and so on mechanical drawing, kinematics, engineerig material, materials mechanics and machine manufacture technology has the deep elementary knowledge.

One of the first steps in the design of any product is to select the material from which each part is to be made. Numerous materials are available to today's designers. The function of the product, its appearance, the cost of the material, and the cost of fabrication are important in making a selection. A careful evaluation of the properties of a. material must be made prior to any calculations.

Careful calculations are necessary to ensure the validity of a design. In case of any part failures, it is desirable to know what was done in originally designing the defective components. The checking of calculations (and drawing dimensions) is of utmost importance. The misplacement of one decimal point can ruin an otherwise acceptable project. All aspects of design work should be checked and rechecked.

The computer is a tool helpful to mechanical designers to lighten tedious calculations, and provide extended analysis of available data. Interactive systems, based on computer capabilities, have made possible the concepts of computer aided design (CAD) and

computer-aided manufacturing (CAM).How does the psychologist frequently discuss causes the machine which the people adapts them to operate. Designs personnel''s basic responsibility is diligently causes the machine to adapt the people. This certainly is not an easy work, because

certainly does not have to all people to say in fact all is the most superior operating area and the operating process.Another important question, project engineer must be able to carry on the exchange and the consultation with other concerned personnel. In the initial stage, designs the personnel to have to carry on the exchange and the consultation on the preliminary design with the administrative personnel, and is approved. This generally is through the oral discussion, the schematic diagram and the writing material carries on.

If front sues, the machine design goal is the production can meet the human need the product. The invention, the discovery and technical knowledge itself certainly not necessarily can bring the advantage to the humanity, only has when they are applied can produce on the product the benefit. Thus, should realize to carries on before the design in a specific product, must first determine whether the people do need this kind of product

Must regard as the machine design is the machine design personnel carries on using creative ability the product design, the system analysis and a formulation product manufacture technology good opportunity. Grasps the project elementary knowledge to have to memorize some data and the formula is more important than. The merely service data and the formula is insufficient to the completely decision which makes in a good design needs. On the other hand, should be earnest precisely carries on all operations. For example, even if places wrong a decimal point position, also can cause the correct design to turn wrongly.

A good design personnel should dare to propose the new idea, moreover is willing to undertake the certain risk, when the new method is not suitable, use original method. Therefore, designs the personnel to have to have to have the patience, because spends the time and the endeavor certainly cannot guarantee brings successfully. A brand-new design, the request screen abandons obsoletely many, knows very well the method for the people. Because many person of conservativeness, does this certainly is not an easy matter. A mechanical designer should unceasingly explore the improvement existing product the method, should earnestly choose originally, the process confirmation principle of design in this process, with has not unified it after the confirmation new idea.

冲压模具技术外文翻译(含外文文献)

前言 在目前激烈的市场竞争中,产品投入市场的迟早往往是成败的关键。模具是高质量、高效率的产品生产工具,模具开发周期占整个产品开发周期的主要部分。因此客户对模具开发周期要求越来越短,不少客户把模具的交货期放在第一位置,然后才是质量和价格。因此,如何在保证质量、控制成本的前提下加工模具是值得认真考虑的问题。模具加工工艺是一项先进的制造工艺,已成为重要发展方向,在航空航天、汽车、机械等各行业得到越来越广泛的应用。模具加工技术,可以提高制造业的综合效益和竞争力。研究和建立模具工艺数据库,为生产企业提供迫切需要的高速切削加工数据,对推广高速切削加工技术具有非常重要的意义。本文的主要目标就是构建一个冲压模具工艺过程,将模具制造企业在实际生产中结合刀具、工件、机床与企业自身的实际情况积累得高速切削加工实例、工艺参数和经验等数据有选择地存储到高速切削数据库中,不但可以节省大量的人力、物力、财力,而且可以指导高速加工生产实践,达到提高加工效率,降低刀具费用,获得更高的经济效益。 1.冲压的概念、特点及应用 冲压是利用安装在冲压设备(主要是压力机)上的模具对材料施加压力,使其产生分离或塑性变形,从而获得所需零件(俗称冲压或冲压件)的一种压力加工方法。冲压通常是在常温下对材料进行冷变形加工,且主要采用板料来加工成所需零件,所以也叫冷冲压或板料冲压。冲压是材料压力加工或塑性加工的主要方法之一,隶属于材料成型工程术。 冲压所使用的模具称为冲压模具,简称冲模。冲模是将材料(金属或非金属)批量加工成所需冲件的专用工具。冲模在冲压中至关重要,没有符合要求的冲模,批量冲压生产就难以进行;没有先进的冲模,先进的冲压工艺就无法实现。冲压工艺与模具、冲压设备和冲压材料构成冲压加工的三要素,只有它们相互结合才能得出冲压件。 与机械加工及塑性加工的其它方法相比,冲压加工无论在技术方面还是经济方面都具有许多独特的优点,主要表现如下; (1) 冲压加工的生产效率高,且操作方便,易于实现机械化与自动化。这是

机械手机械设计中英文对照外文翻译文献

(文档含英文原文和中文翻译) 中英文对照翻译 机械设计 摘要: 机器由机械和其他元件组成的用来转换和传输能量的装置。比如:发动机、涡轮机、车、起重机、印刷机、洗衣机和摄影机。许多机械方面设计的原则和方法也同样适用于非机械方面。术语中的“构造设计”的含义比“机

械设计”更加广泛,构造设计包括机械设计。在进行运动分析和结构设计时要把产品的维护和外形也考虑在机械设计中。在机械工程领域中,以及其它工程领域,都需要机械设备,比如:开关、凸轮、阀门、船舶以及搅拌机等。关键词:设计流程设计规则机械设计 设计流程 设计开始之前就要想到机器的实用性,现有的机器需要在耐用性、效率、重量、速度,或者成本上得到改善。新的机器必需能够完全或部分代替以前人的功能,比如计算、装配、维修。 在设计的初级阶段,应该充分发挥设计人员的创意,不要受到任何约束。即使有一些不切实际的想法,也可以在设计的早期,即在绘制图纸之前被改正掉。只有这样,才不致于阻断创新的思路。通常,必须提出几套设计方案,然后进行比较。很有可能在这个计划最后指定使用某些不在计划方案内的一些想法的计划。 一般当产品的外型和组件的尺寸特点已经显现出来的时候,就可以进行全面的设计和分析。接着还要客观的分析机器性能、安全、重量、耐用性,并且成本也要考虑在内。每一个至关重要的部分要优化它的比例和尺寸,同时也要保持与其它组成部分的平衡。 选择原材料和工艺的方法。通过力学原理来分析和实现这些重要的特性,如稳定和反应的能量和摩擦力的利用,动力惯性、加速度、能量;包括材料的弹性强度、应力和刚度等物理特性,以及流体的润滑和驱动器的流体力学。设计的过程是一个反复与合作的过程,无论是正式的还是非正式的,对设计者来说每个阶段都很重要。。产品设计需要大量的研究和提升。许多的想法,必须通过努力去研究成为一种理念,然后去使用或放弃。虽然每个工

外文翻译

Load and Ultimate Moment of Prestressed Concrete Action Under Overload-Cracking Load It has been shown that a variation in the external load acting on a prestressed beam results in a change in the location of the pressure line for beams in the elastic range.This is a fundamental principle of prestressed construction.In a normal prestressed beam,this shift in the location of the pressure line continues at a relatively uniform rate,as the external load is increased,to the point where cracks develop in the tension fiber.After the cracking load has been exceeded,the rate of movement in the pressure line decreases as additional load is applied,and a significant increase in the stress in the prestressing tendon and the resultant concrete force begins to take place.This change in the action of the internal moment continues until all movement of the pressure line ceases.The moment caused by loads that are applied thereafter is offset entirely by a corresponding and proportional change in the internal forces,just as in reinforced-concrete construction.This fact,that the load in the elastic range and the plastic range is carried by actions that are fundamentally different,is very significant and renders strength computations essential for all designs in order to ensure that adequate safety factors exist.This is true even though the stresses in the elastic range may conform to a recognized elastic design criterion. It should be noted that the load deflection curve is close to a straight line up to the cracking load and that the curve becomes progressively more curved as the load is increased above the cracking load.The curvature of the load-deflection curve for loads over the cracking load is due to the change in the basic internal resisting moment action that counteracts the applied loads,as described above,as well as to plastic strains that begin to take place in the steel and the concrete when stressed to high levels. In some structures it may be essential that the flexural members remain crack free even under significant overloads.This may be due to the structures’being exposed to exceptionally corrosive atmospheres during their useful life.In designing prestressed members to be used in special structures of this type,it may be necessary to compute the load that causes cracking of the tensile flange,in order to ensure that adequate safety against cracking is provided by the design.The computation of the moment that will cause cracking is also necessary to ensure compliance with some design criteria. Many tests have demonstrated that the load-deflection curves of prestressed beams are approximately linear up to and slightly in excess of the load that causes the first cracks in the tensile flange.(The linearity is a function of the rate at which the load is applied.)For this reason,normal elastic-design relationships can be used in computing the cracking load by simply determining the load that results in a net tensile stress in the tensile flange(prestress minus the effects of the applied loads)that is equal to the tensile strength of the concrete.It is customary to assume that the flexural tensile strength of the concrete is equal to the modulus of rupture of the

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附录一英文科技文献翻译 英文原文: Experimental investigation of laser surface textured parallel thrust bearings Performance enhancements by laser surface texturing (LST) of parallel-thrust bearings is experimentally investigated. Test results are compared with a theoretical model and good correlation is found over the relevant operating conditions. A compari- son of the performance of unidirectional and bi-directional partial-LST bearings with that of a baseline, untextured bearing is presented showing the bene?ts of LST in terms of increased clearance and reduced friction. KEY WORDS: ?uid ?lm bearings, slider bearings, surface texturing 1. Introduction The classical theory of hydrodynamic lubrication yields linear (Couette) velocity distribution with zero pressure gradients between smooth parallel surfaces under steady-state sliding. This results in an unstable hydrodynamic ?lm that would collapse under any external force acting normal to the surfaces. However, experience shows that stable lubricating ?lms can develop between parallel sliding surfaces, generally because of some mechanism that relaxes one or more of the assumptions of the classical theory. A stable ?uid ?lm with su?cient load-carrying capacity in parallel sliding surfaces can be obtained, for example, with macro or micro surface structure of di?erent types. These include waviness [1] and protruding microasperities [2–4]. A good literature review on the subject can be found in Ref. [5]. More recently, laser surface texturing (LST) [6–8], as well as inlet roughening by longitudinal or transverse grooves [9] were suggested to provide load capacity in parallel sliding. The inlet roughness concept of Tonder [9] is based on ??e?ective clearance‘‘ reduction in the sliding direction and in this respect it is identical to the par- tial-LST concept described in ref. [10] for generating hydrostatic e?ect in high-pressure mechanical seals. Very recently Wang et al. [11] demonstrated experimentally a doubling of the load-carrying capacity for the surface- texture design by reactive ion etching of SiC

机械设计外文翻译(中英文)

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密级 分类号 编号 成绩 本科生毕业设计 (论文) 外文翻译 原文标题Simple Manipulator And The Control Of It 译文标题简易机械手及控制 作者所在系别机械工程系 作者所在专业xxxxx 作者所在班级xxxxxxxx 作者姓名xxxx 作者学号xxxxxx 指导教师姓名xxxxxx 指导教师职称副教授 完成时间2012 年02 月 北华航天工业学院教务处制

译文标题简易机械手及控制 原文标题 Simple Manipulator And The Control Of It 作者机电之家译名JDZJ国籍中国 原文出处机电之家 中文译文: 简易机械手及控制 随着社会生产不断进步和人们生活节奏不断加快,人们对生产效率也不断提出新要求。由于微电子技术和计算软、硬件技术的迅猛发展和现代控制理论的不断完善,使机械手技术快速发展,其中气动机械手系统由于其介质来源简便以及不污染环境、组件价格低廉、维修方便和系统安全可靠等特点,已渗透到工业领域的各个部门,在工业发展中占有重要地位。本文讲述的气动机械手有气控机械手、XY轴丝杠组、转盘机构、旋转基座等机械部分组成。主要作用是完成机械部件的搬运工作,能放置在各种不同的生产线或物流流水线中,使零件搬运、货物运输更快捷、便利。 一.四轴联动简易机械手的结构及动作过程 机械手结构如下图1所示,有气控机械手(1)、XY轴丝杠组(2)、转盘机构(3)、旋转基座(4)等组成。 图1.机械手结构 其运动控制方式为:(1)由伺服电机驱动可旋转角度为360°的气控机械手(有光电传感器确定起始0点);(2)由步进电机驱动丝杠组件使机械手沿X、Y轴移动(有x、y轴限位开关);(3)可回旋360°的转盘机构能带动机械手及丝杠组自由旋转(其电气拖动部分由直流电动机、光电编码器、接近开关等组成);(4)旋转基座主要支撑以上3部分;(5)气控机械手的张合由气压控制(充气时机械手抓紧,放气时机械手松开)。 其工作过程为:当货物到达时,机械手系统开始动作;步进电机控制开始向下

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外文出处: 《Exploiting Software How to Break Code》By Greg Hoglund, Gary McGraw Publisher : Addison Wesley Pub Date : February 17, 2004 ISBN : 0-201-78695-8 译文标题: JDBC接口技术 译文: JDBC是一种可用于执行SQL语句的JavaAPI(ApplicationProgrammingInterface应用程序设计接口)。它由一些Java语言编写的类和界面组成。JDBC为数据库应用开发人员、数据库前台工具开发人员提供了一种标准的应用程序设计接口,使开发人员可以用纯Java语言编写完整的数据库应用程序。 一、ODBC到JDBC的发展历程 说到JDBC,很容易让人联想到另一个十分熟悉的字眼“ODBC”。它们之间有没有联系呢?如果有,那么它们之间又是怎样的关系呢? ODBC是OpenDatabaseConnectivity的英文简写。它是一种用来在相关或不相关的数据库管理系统(DBMS)中存取数据的,用C语言实现的,标准应用程序数据接口。通过ODBCAPI,应用程序可以存取保存在多种不同数据库管理系统(DBMS)中的数据,而不论每个DBMS使用了何种数据存储格式和编程接口。 1.ODBC的结构模型 ODBC的结构包括四个主要部分:应用程序接口、驱动器管理器、数据库驱动器和数据源。应用程序接口:屏蔽不同的ODBC数据库驱动器之间函数调用的差别,为用户提供统一的SQL编程接口。 驱动器管理器:为应用程序装载数据库驱动器。 数据库驱动器:实现ODBC的函数调用,提供对特定数据源的SQL请求。如果需要,数据库驱动器将修改应用程序的请求,使得请求符合相关的DBMS所支持的文法。 数据源:由用户想要存取的数据以及与它相关的操作系统、DBMS和用于访问DBMS的网络平台组成。 虽然ODBC驱动器管理器的主要目的是加载数据库驱动器,以便ODBC函数调用,但是数据库驱动器本身也执行ODBC函数调用,并与数据库相互配合。因此当应用系统发出调用与数据源进行连接时,数据库驱动器能管理通信协议。当建立起与数据源的连接时,数据库驱动器便能处理应用系统向DBMS发出的请求,对分析或发自数据源的设计进行必要的翻译,并将结果返回给应用系统。 2.JDBC的诞生 自从Java语言于1995年5月正式公布以来,Java风靡全球。出现大量的用java语言编写的程序,其中也包括数据库应用程序。由于没有一个Java语言的API,编程人员不得不在Java程序中加入C语言的ODBC函数调用。这就使很多Java的优秀特性无法充分发挥,比如平台无关性、面向对象特性等。随着越来越多的编程人员对Java语言的日益喜爱,越来越多的公司在Java程序开发上投入的精力日益增加,对java语言接口的访问数据库的API 的要求越来越强烈。也由于ODBC的有其不足之处,比如它并不容易使用,没有面向对象的特性等等,SUN公司决定开发一Java语言为接口的数据库应用程序开发接口。在JDK1.x 版本中,JDBC只是一个可选部件,到了JDK1.1公布时,SQL类包(也就是JDBCAPI)

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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

机械类外文翻译

机械类外文翻译 塑料注塑模具浇口优化 摘要:用单注塑模具浇口位置的优化方法,本文论述。该闸门优化设计的目的是最大限度地减少注塑件翘曲变形,翘曲,是因为对大多数注塑成型质量问题的关键,而这是受了很大的部分浇口位置。特征翘曲定义为最大位移的功能表面到表面的特征描述零件翘曲预测长度比。结合的优化与数值模拟技术,以找出最佳浇口位置,其中模拟armealing算法用于搜索最优。最后,通过实例讨论的文件,它可以得出结论,该方法是有效的。 注塑模具、浇口位臵、优化、特征翘曲变形关键词: 简介 塑料注射成型是一种广泛使用的,但非常复杂的生产的塑料产品,尤其是具有高生产的要求,严密性,以及大量的各种复杂形状的有效方法。质量ofinjection 成型零件是塑料材料,零件几何形状,模具结构和工艺条件的函数。注塑模具的一个最重要的部分主要是以下三个组件集:蛀牙,盖茨和亚军,和冷却系统。拉米夫定、Seow(2000)、金和拉米夫定(2002) 通过改变部分的尼斯达到平衡的腔壁厚度。在平衡型腔充填过程提供了一种均匀分布压力和透射电镜,可以极大地减少高温的翘曲变形的部分~但仅仅是腔平衡的一个重要影响因素的一部分。cially Espe,部分有其功能上的要求,其厚度通常不应该变化。 pointview注塑模具设计的重点是一门的大小和位臵,以及流道系统的大小和布局。大门的大小和转轮布局通常被认定为常量。相对而言,浇口位臵与水口大小布局也更加灵活,可以根据不同的零件的质量。 李和吉姆(姚开屏,1996a)称利用优化流道和尺寸来平衡多流道系统为multiple 注射系统。转轮平衡被形容为入口压力的差异为一多型腔模具用相同的蛀牙,也存

机械手设计英文参考文献原文翻译

机械手设计英文参考文 献原文翻译 Company number:【WTUT-WT88Y-W8BBGB-BWYTT-19998】

翻译人:王墨墨山东科技大学 文献题目:Automated Calibration of Robot Coordinates for Reconfigurable Assembly Systems 翻译正文如下: 针对可重构装配系统的机器人协调性的自动校准 T.艾利,Y.米达,H.菊地,M.雪松 日本东京大学,机械研究院,精密工程部 摘要 为了实现流水工作线更高的可重构性,以必要设备如机器人的快速插入插出为研究目的。当一种新的设备被装配到流水工作线时,应使其具备校准系统。该研究使用两台电荷耦合摄像机,基于直接线性变换法,致力于研究一种相对位置/相对方位的自动化校准系统。摄像机被随机放置,然后对每一个机械手执行一组动作。通过摄像机检测机械手动作,就能捕捉到两台机器人的相对位置。最佳的结果精度为均方根值毫米。 关键词: 装配,校准,机器人 1 介绍 21世纪新的制造系统需要具备新的生产能力,如可重用性,可拓展性,敏捷性以及可重构性 [1]。系统配置的低成本转变,能够使系统应对可预见的以及不可预见的市场波动。关于组装系统,许多研究者提出了分散的方法来实现可重构性[2][3]。他们中的大多数都是基于主体的系统,主体逐一协同以建立一种新的

配置。然而,协同只是目的的一部分。在现实生产系统中,例如工作空间这类物理问题应当被有效解决。 为了实现更高的可重构性,一些研究人员不顾昂贵的造价,开发出了特殊的均匀单元[4][5][6]。作者为装配单元提出了一种自律分散型机器人系统,包含多样化的传统设备[7][8]。该系统可以从一个系统添加/删除装配设备,亦或是添加/删除装配设备到另一个系统;它通过协同作用,合理地解决了工作空间的冲突问题。我们可以把该功能称为“插入与生产”。 表1:合作所需的调节和量度 在重构过程中,校准的装配机器人是非常重要的。这是因为,需要用它们来测量相关主体的特征,以便在物理主体之间建立良好的协作关系。这一调整必须要达到表1中所列到的多种标准要求。受力单元和方向的调整是不可避免的,以便使良好的协同控制得以实现。从几何标准上看,位置校准是最基本的部分。一般来说,校准被理解为“绝对”,即,关于特定的领域框架;或者“相对”,即,关于另一个机器人的基本框架。后者被称为“机器人之间的校准”。 个体机器人的校准已被广泛研究过了。例如,运动参数的识别就非常受欢迎。然而,很少有对机器人之间校准的研究。玉木等人是用一种基于标记的方法,在一个可重构的装配单元内,校准机器人桌子和移动机械手之间的相互位置/方向联系。波尼兹和夏发表了一种校准方法。该方法通过两个机械手的机械接触来实现,实验非常耗时,并要求特别小心地操作。

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河南科技学院新科学院 2013届本科毕业生论文(设计) 英文文献及翻译 Foreign capital inflows and welfare in an economy with imperfect competition 学生姓名:王艳杰 所在院系:经济系 所学专业:国际经济与贸易 导师姓名:侯黎杰 完成时间:2013年4月15日

Foreign capital inflows and welfare in an economy with imperfect competition Abstract:This paper examines the resource allocational and welfare effects of exogenous inflows of foreign capital in a general-equilibrium model with oligopolistic competition and unemployment. Although the welfare impact for the short run is ambiguous and dependent upon the strength of excess profits and scale economies relative to unemployment in manufacturing, in the long run additional inflows of foreign capital always improve national welfare with capital mobility. Hence, attracting foreign capital remains a sound policy for economies characterized by imperfect competition, scale economies,and regional unemployment. Keywords: International capital mobility; Imperfect competition; Welfare 1.Introduction The welfare effects of exogenous inflows of foreign capital in the presence of trade restrictions have been extensively studied. Brecher and Diaz Alejandro (1977) show that when imports are subject to tariffs, an introduction of fo reign capital inflows accentuates the tariff distortion and hence reduces national welfare if the import-competing sector is relatively capital-intensive. In contrast, Dei (1985) shows that when imports are restricted by quotas,foreign capital inflows in the presence of foreign-owned capital always improve welfare by depressing the rental and so lowering the payments to existing foreign-owned capital. Recently, Neary (1981), using a common framework for both tariffs and quotas, obtains more general results of foreign capital inflows; the welfare effect of such inflows depends crucially on whether foreign-owned capital exists initially in the home country. In addition, Khan (1982) and Grinols (1991) have examined the effects of foreign capital inflows for a generalized Harris-Todaro economy under tariff protection. Khan finds that the result by Brecher and Diaz Alejandro is still valid even in the presence of unemployment, whereas Grinols argues that increased foreign capital need not be detrimental to welfare if the opportunity costs of labor are sufficiently low. Noteworthy is that the models used by these authors are all based upon the premise of perfect competition along with constant returns-to-scale technology. Although perfect competition serves as a useful assumption in crystallizing theoretical insights, it nevertheless fails to depict many of the real-world phenomena. The real-world economy is characterized, to a large extent, by imperfect competition and economies of scale. The policy implications of imperfect competition and economies

机械类毕业设计外文文献翻译

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

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