毕业论文外文翻译--机器人.doc

《毕业论文外文翻译--机器人.doc》由会员分享，可在线阅读，更多相关《毕业论文外文翻译--机器人.doc（17页珍藏版）》请在淘文阁 - 分享文档赚钱的网站上搜索。

1、天津职业技术师范大学2012届本科生毕业设计英文资料与中文翻译Robotics1、The Robotics ApplicationMany of the robots in use today do jobs that are especially difficult for human workers. These are the types of jobs that require great strength or pose danger. For example, robots are particularly useful in the auto-manufacturing indu

2、stry where parts of automobiles must be welded together. A welding tool used by a human worker weighs about 100 pounds or more and is difficult to handle. As mechanical supermen, robots may be called upon to do anything from moving heavy components between workstations on a factory floor to carrying

3、 bags of cement.Spray painting is another task suited to robots because robots do not need to breathe. Unlike human painters, they are unaffected by the poisonous fumes. Robots are better at this task, not because they are faster or cheaper than humans, but because they work in a place where humans

4、cannot.Third in the list of useful jobs for robots is the assembly of electronic parts. Robots shine at installing chips in printed circuit boards because of a capability that robots have that people dont. A robot, once properly programmed, will mot put a chip in the wrong place. This automatic accu

5、racy is particularly valuable in this kind of industry because locating and fixing mistakes is costly2、Robotics RevolutionEarlier robots were usually blind and deaf, but newer types of robots are fitted with video cameras and other sensing devices that can detect heat, texture, size, and sound. Thes

6、e robots are used in space projects, nuclear reactor stations, and underwater exploration research.In their efforts to expand the range of robotic applications, researchers are looking beyond traditional designs to examine a variety of potential models from the biological word. The industrial arm is

7、 a classic example. Scientists have been able to model robots to imitate the vertebrate spine of a snake in order to paint the interior of automobiles. They have simulated the muscle structure and movement of and elephants trunk in am attempt to create a robotic arm capable of lifting heavy objects.

8、 Scientists also emulate the flexibility of an octopus where the tentacles can conform to the fragile objects of any shape and hold them with uniform, gentle pressure. A variation of this design can be used to handle animals, turn hospital patients in their beds, or lift a small child.The challenger

9、 of equipping robots with the skills to operate independently, outside of a factory or laboratory, has taxed the ingenuity and creativity of academic, military, and industrial scientists for years. Simply put robot handslike robot legs, or eyes, or reasoning powershave long way to go before they can

10、 approach what biological evolution has achieved over by the course of hundreds of millions of years. Much more will have to happen in laboratories around the world before the robots can be compared to natures handiwork.In the meantime, the robotics revolution is already beginning to change the kind

11、 of work that people do. The boring and dangerous jobs are now assumed by robots. By the not do. There are also some industrialists who hope that by the year 2000 all their employees will be knowledge workers, no longer standing on assembly lines but rather sitting at desks and computer terminals to

12、 deal with information. These changes are already under way, and their pace accelerates every year.3、Intelligent Robots A new phase in robot applications has been opened with the development of “intelligent robots”. An intelligent robot is basically one that must be capable of sensing its surroundin

13、g and possesses intelligence enough to respond to a changing to a changing environment in much the same way as we do. Such ability requires the direct application of sensory perception and artificial intelligence. Much of research in robotics has been and is still concerned with how to equip robots

14、with visual sensorseyes and tactile sensorsthe “fingers”. Artificial intelligence will enable the robot to respond to and adapt to changes in its task and in its environment, and to reason and made decisions in reaction to those changes.4、Visional Sensory Much effort has been made to simulate simila

15、r human sensory abilities for intelligent robots. Among them, vision is the most important sense as it is estimated that up go 80% of sensory information is received by vision. Vision can be bestowed on robotic systems by using imaging sensors in various ways. For improving accuracy of performances,

16、 it can help precisely adjust the robot hand by means of optical feedback control using visual sensors. Determining the location, orientation, and recognition of the parts to be picked up is another important application.Among the vision system, one of the key components is imagery sensor. The image

17、ry sensor of a robot system is defined as an electro-optical device that converts an optical image to a video signal. The image sensor is usually either a TV-camera of a solid state sensory device, for example, charge-couple devices (CCD). The latter device offers greater .sensitivity, long enduranc

18、e and lightweight, and is thus welcome when compared with the TV-camera. The camera system contains not only the camera detector but also, and very importantly, a lens system. The lens determines the field of view, the depth of focus, and other optical factors that directly affect the quality of the

19、 image detected by the camera.Either TV-camera or CCDs produce an image by generating an analogue value on every pixel, proportional to its light intensity. To enable a digital computer to work with this signal, an analogue-to-digital (A/D) converter is needed to transfer analogue into digital data,

20、 then store in random access memory (RAM), installed in computer. The computer analyzes the data and extracts such imagery information as edges, regions, colors and textures of the objects in the image. Finally, the computer interprets or understands what the image represents in terms of knowledge a

21、bout the scene and gives the robot a symbolic description of its environment.5、Tactile Sensory Next to vision in importance is tactile sensing or touching. Imagine the blind can do delicate jobs relying on his/her sensitive tactile. A blind robot can be extremely effective in performing an assembly

22、task using only a sense of touch. Touch is of particular importance for providing feedback necessary to grip delicate objects firmly without causing damage to them. To simulate tactile in human hands, a complete tactile-sensing system must perform three fundamental sensing operations: (1) joint forc

23、e sensing which senses the force applied to the robots hand, wrist and arm joints; (2) touch sensing which senses the pressure applied to various points on the hands surface or the grippers surface; (3) slip sensing which senses any movement of the object while it is being grasped. The joint forces

24、are usually sensed using various strain gauges arranged in robot wrist assembly. A strain gauge is a forcesensing element whose resistance change in proportion to the amount of the force applied to the element. The simplest application of touch sensor is a gripper equipped with an array of miniature

25、 microswitches. This type of sensor can only determine the presence or absence of an object at a particular point or an array of points of the robot hand. A more advanced type of touch sensors uses arrays of pressure-sensitive piezoelectric material (conductive rubber or foam, etc.). The arrangement

26、 allows the sensor to perceive changes in force and pressure within the robot hand. Since the force at each point can be determined, the force on its surface can be mapped and the shapes of objects grasped in the robot hand can be determined respectively. Slip sensing is required for a robot to crea

27、te the optimum amount of grasping force applied to be picked up without the danger of being dropped. The gripping force is increased step by step until the object has been firmly grasped and no more slip occurs. The integration of tactile sensing and vision sensing can dramatically enhance robotic a

28、ssembly task. An example of this type of sensors would be a vision sensor used to locate and identify objects and positing of the robot itself, combined with a tactile sensor used to detect the distribution of force and pressure, and determine torque, weight, center of mass and compliance of the mat

29、erial it handles. The hand-eye coordination for general-purpose manipulation will be extremely powerful in the industrial world. 机器人1、机器人的应用许多今天使用的机器人在做一些对工人特别困难的工作。这些类型的工作需要很大的力量，或者有危险。比如，在需要将汽车零件焊接在一起的自动生产工业中，机器人就特别人用，工人使用的焊接工具重约100磅，或更重，并且很难操作。作为机械巨人，机器人可被呼唤去做任何事情，从一工场的工作站点之间移动笨重部件到运送袋装的水泥。由于机器人不

30、需呼吸，所以喷涂是另一个适合机器人的任务，不像油漆工，机器人不受有毒气体的影响。机器人更优于完成这种工作，不但因为它们比人做得更快更便宜，而且因为能在人不能工作的地方进行工作。适合于机器人工作中，第三个项目是装配电子元件。机器人能很好地将芯片装配在七印刷电路板上，因为它具备人所没有具备的能力。一旦适当地编程，机器人就不会将芯片放错地方。这种自动的精度在这种类型的工业中特别有价值，因为定位和安装错误代价是很高的。2、机器人革命早期的机器人又瞎又聋，但新型机器人安装有电视摄像机和其它传感器设备，因而能感知热、结构、尺寸和声音，这些机器人用于空间计划、核反应站和水下探测研究。在扩大机器人应用范围的尝

31、试中，研究者正超越传统设计，并考察源生物世界的各种潜在的模型，工业机械手是一典型例子。科学家已能让机器人模仿蛇的脊椎，以油漆汽车内部。在着力建造能举起笨重物体的机器人的手臂时，他们模仿肌肉结构和大象鼻子的运动。科学家还模拟章鱼的灵活性，其触角能用于任何形状的易碎品，并用均匀且轻柔的压力握住这些易碎品。这种设计的一种变化能用于抱起动物，给医院中病床上的病人翻身，或抱起小孩。将机器人安装可在工厂或实验室外独立操作的技能，这一挑战已花费了学术界、军事界和工业界的科学家们的智谋和创造性。简单来说，机器人的手如同机器人的腿、眼睛或推理能力。在接近经过成亿年生物进化所获得的能力之前，还有很长的路要走。在机

32、器人能和自然的杰作相比之前，世界各地的实验室中还需完成许多工作。同时，机器人的进展已开始转变人所做的工作，令人厌烦和危险的工作已由机器人承担。在世纪之交，更多的人要去完成机器人所不能完成的任务。已有许多工业家希望到2000年，所有雇员都是知识工，不再站在装配线前，而是坐在桌子和计算机终端前处理信息。这些变化已经存在，而且其步伐每年都在加快。3、智能机器人一个机器人应用 中的新局面随着“智能机器人”的发展而已打开。一个智能机器人基本上能感知环境并且具有足够的智力，像我们人一样能对变化中的环境做出响应。这种能力要求直接使用感觉和人工智能。许多机器人的研究羽绒并且仍然关注如何在机器人中装备视觉传感器

33、眼睛和触觉传感器“手指”。人工智能能将使机器人能响应并适应其工作任务和环境变化，并且能按照这些变化的反应进行推理和做出决定。4、视觉传感为使机器人模仿人的感觉能力人的感觉能力，己做了很多的努力。其中，视觉是最重要的感觉，因为据估计，接近80的感觉信息是由视觉收到的。在机器人系统中设置视觉可由各种形式的图像传感器来完成。为了改善运行的精度，通过视觉传感器的光学反馈控制，可精密地调整机器人手臂。决定位置、方向和辨别所要选取的零件则是另一重要的应用。在视觉系统中，关键部件之一是图像器。机器人系统中图像传感器的定义为将常常图像转换成视频信号的电-光学器件。图像传感器通常为电视摄像机，或固态传感器件，如

34、电荷耦合器件（CCD）。后一种器件提供更高的灵敏度、较长的耐久性和较轻的重量，因而与电视摄像机相比更受欢迎。摄像系统不但包括摄像探测器，而且更重要的是包括光学透镜系统。这种透镜决定视场、定焦深度和其它直接影响摄像机所摄取图像质量的光学特性。无论电视摄像机还是CCD都会通过在每一像素点形成与光强成正比的模拟量而产生图像。要使数字计算机对这信号起作用，需要模拟数字（AD）转换器将模拟数据转换成数字信息，如边界、区域、颜色，以及图像中物体结构。最后，计算机能就场景的辨别、理解图像所表示的含义或做出解释，使机器人用符号对环境描述。5、接触感觉重要性仅次于视觉是接触感觉，或触感。想象一下盲人能依靠灵敏的

35、触觉来做精细的工作。无视学机器人能只用触觉极有效地完成装配任务，对于需要反馈来紧紧握住精致脆弱的物体而不会损坏它们的用途，触觉具有独特的重重性。为了模拟人手的触觉，一个完整的接触传感系统必须完成三个基本操作：（1）关节的力觉，检测加在机器人的手、腕和臂关节上的力；（2）触觉检测，加在手平面或者夹持器平面各个点上的压力；（3）滑觉，检测所抓取的物体的任何滑动。关节上的力通常用各种布置在机器人夹手零件上的应变测力计来检测。应变测力计是一种测力元件，其电阻变化与加在元件上的力大小成比例。最简易的触觉传感器是用细小的微型开关阵列组成的夹持器。这种传感器只能决定物体是否在机器人手上的点阵中某个特殊点上存

36、在。更为先进的触觉传感器使用压敏的压电材料（如导电橡胶或泡沫等）。其排列使传感器能感觉机器人手中的力和压力的变化。既然各点的力可以决定，所以手掌面上的力就可以被图像化地获得，并由此决定机器人手中所握的各物体形状。对于产生一个用精致脆弱物体的最佳握持力，机器人需要滑觉。于这种能力避免损坏物体，并能抓起物体面不会有掉下的危险。夹持力一步一步增加，直至物体被紧紧地失信抓住而不再滑动。触觉和视觉的集成能极大的提高机器人装配工作，这类传感器的一例是视觉传感器，用于对物体和机器人本身的定位和辨别；并结合触觉传感器用于探测力和压力的分布和确定力矩、重量、质量、重心，按所抓取的材料决定握持力。这种用于通用的手

37、眼配合操作在工业界将会变得极为有效力。 Installation and Maintenance of PLCTodays programmable controller, properly installed, will provide a maximum of productivity with a minimum of maintenance. This section will cover the strength forward but critical areas of installation and maintenance of the programmable control

38、ler. It is intended to serve only as an overview on the subject, with the best guide for use being the documentation provided by the programmable controller manufacturer. This section will include rack installation for the CPU and I/O racks involved, line power, grounding, and signal cable considera

39、tion. Troubleshooting techniques as well as repair situation will be examined, and finally, training options will be presented.1. Rack InstallationDepending on the size of the programmable controller being considered, the installation of the racks or chassis can be a simple or very complex task. Sin

40、ce most controllers are of open or particular application area. Many times this is a NEMA 12 type enclosure. It provides an environment in which the controller can operate without exposure to the grime outside the enclosure. Most racks can be mounted in either a panel type mounting arrangement, or a

41、 19 in rack mounting. This is not true of controllers of the very small variety, as they are normally a panel mount only design. Rack mounting is generally used where the equipment is otherwise controlled. This type of installation is common where many instruments are mounted and used along with the

42、 programmable controller equipment. In either case, wire conductors must be routed in the rack; this is done with commercially available conduit that provides a means to bring in and out as many as 100 to 200 individual conductors from input and output points to real-world sensors and actuators. It

43、is important that this phase of the design and installation be handled with care as it will dramatically affect the ability to maintain the systems. In addition to allowing any required system maintenance, this early care will make any system additions or modifications much easier.2. Line Power and

44、Grounding Proper power to the programmable controller is critical. Todays systems are available in a wide variety of electrical configurations. Virtually all are designed for use in single-phase power systems, and most are now beginning to be offered with the optional ability to operate in a DC supp

45、ly environment. AC designs are offered in either single voltage supplies, such as 115 or 230V AC; while some can be configured as either through a selection made on the power supply. Proper grounding of the power supply connection is required for a safe installation. Some programmable controller des

46、igns have individual grounding connections from rack to face- plates and other system components, so care must be taken to follow well electrical practice in system grounding during electrical installation. In certain applications, a 24 or 120 V DC power supply is required. This is common for instal

47、lations that axe made where no AC power is available, such as remote electrical generation stations. It is also found where AC power is unreliable and where loss of control is considered an unacceptable situation3. Signal Cable Connections The chain must be completed and have high integrity to provi

48、de the communication path for control signals to pass over. Depending on the specific design of the programmable control system, loss of communication to the I/O system will cause a critical failure, stopping the CPU scan .In other systems, configurations can be accomplished that allow the unaffecte

49、d portions of the programmable controller system to continue to operate. As we saw earlier, communication between chassis can either be parallel or serial. Parallel communication uses multiple conductors to pass all bits of a byte or word of data simultaneously. Serial communication provides a method for single bits of a byte or word of data simultaneo