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Industrial robotsThere are variety of definitions of the term robot. Depending on the definition used, the number of robot installations worldwide varies widely. Numerous single-purpose machines are used in manufacturing plants that might appear to be robots. These machines are hardwried to perform a single function and cannot be reprogrammed to preform a different function. Such single-purpose machines do not fit the definition for industrial robots that is becoming widely accepted.this definition was developed by the Robot Institute of America. A robot is a reprogrammable multifunctional mainipulator designed to move material, parts, tools, or specialized devices through variable programmed motions for the performance of a variety of tasks. Note that this definition contains the words reprogrammable and multifunctional. It is these two characteristics that separate the ture industrial robot from the various single-purpose machines used in modern manufacturing firms. The term “reprogrammable” implies two things: The robot operates according to a written program, and this program can be rewritten to accommodate a variety of manufactureing tasks. The term “multifunctional” means that the robot can, through reprogramming and the use of different end-effectors, perform a number of different manufacturing tasks. Definitions written around these two critical characteristics are becoming the accpted definitions among manufacturing professionals. The first articulated arm came about in 1951 and was used by the U. S. Atomic Energy Commission. In 1954, the first programmable robot was designed by George Devol. It was based on two important technologies:(1) Numerical control (NC) technology.(2) Romote manipulator technology.Numerical contorl technology provided a form of machine control ideally suited to robots. It allowed for the control of motion by stored programs. These programs contain date points to which the sequentially moves, timing signals initiate action and to stop movement, and logic staements to allow for decision making.Remote manipulator technology allowed a machine to be more than just another NC machine. It allowed such machines to become robots that can perform a variety of manufacturing tasks in both inaccessible and unsafe environments. By merging these two technologies, Devol developed the first industrial robot, an unsophisticated programmable materials handling machine.The first commerically produced robot was developed in 1959. In 1962, General Motors Corporation. This robot was produced by Unimation. A major step forword in robot control occurred in 1973 with the development of the T-3 industrial robot by Cincinnati Milacron. The T-3 robot was the first commercially produced industrial robot controlled by a minicomputer.Numerical control and remote manipulator technology prompted the wide-scale development and use of industrial robots. But major technological developments do not take place simply because of such new capabilities. Something must provide the impetus for taking advantage of these capabilities. In the case of industrial robots, the impetus was economics.The rapid inflation of wages experienced in the 1970s tremendously increased the personnel costs of manufacturing firms. At the same time, foreign competition became a serious problem for U. S. manufacturers. Foreign manufacturers who had undertaken automation on a wide-scale basis, such as those in Japan, began to gain an increasingly large share of the U. S. and world market for manufactured goods, particularly automobiles.Through a variety of automation techniques including robots, Japanese manufacturers, beginning in the 1970s, were able to produce better automobiles more cheaply than nonautomated U. S. manufacturers. Consequently, in order to survive, U. S. manufacturers were forced to consider any technological developments that could help improve productivity.It became imperative to produce better products at lower costs in order to be competitive with foreign manufacturers. Other factors such as the need to find better ways of performing dangerous manufacturing tasks contributed to the development of industial robots. However, the principal rationale has always been, and is still, improved productivity.One of the principal advantages of robots is that they can be used in settings that are dangerous to humans. Welding and parting are examples of applications where robots can be used more safely than humans. Even though robots are closely associated with safety in the workplace, they can, in themselves, be dangerous.Robots and robot cells must be carefully designed and configured so that they do not endanger human workers and other machines. Robot work envelops should be accurately calculated and a danger zone surrounding the envelope clearly marked off. Red flooring strips and barries can be used to keep human workers out of a robots work envelope.Even with such precautions it is a good idea to have an automatic shutdown system in situations where robots are used. Such a system should have the capacity to sense the need for an automatic shutdown of operations. Fault-tolerant computers and redundant systems can be installed to ensure proper shutdown of robotics systems to ensure a safe enviroment.About componets of a robot system, the componets of a robot system could be discussed either from a systems point of view. Physically, we could divide the system, and controller (computer) . Likewise, the robot itself could be partitioned anthropomorphically into base, shoulder, elbow, wrist, gripper, and tool. Most of these terms require little explanation.Consequently, we will describe the components of a robot system from the point of view of information transfer. That is, what information or signal enters the component; what logical or arithmetic operation does the component perform; and what information or signal does the component produce? It is important to note that the same physical component may performs many different information processing operations ( e. g. , a central computer performs many different calculations on different data ) . Likewise, two physically separate components many perform identical informations ( e .g . , the shoulder and elbow actuators both convert signals to motion in very similar ways ) .中文： 工业机器人有许多关于机器人这个术语的定义。采用不同的定义，全世界各地机器人的数量就会发生很大的改变。在制造工厂中使用的许多但用途机器可能会看起来像机器人。这些机器是硬连线的，用来完成单一的工作，不能通过重新编程的方法去完成不同的工作。这种单用途的机器不能满足被人们日益广泛接受的关于工业机器人的定义。这个定义是由美国机器人协会提出的:机器人是一个可以改编程序的多功能操作器，被设计用来按预先编制的，能够完成多种作业的运动程序运送材料，零件，工具或者专用设备。注意在这个定义中包含有“可以改编程序”和“多功能”这两个词。正是这两个词将真正的机器人与现代制造工厂中使用的单一用途的机器区分开来。“可以改编程序”这个术语意味着两件事：机器人根据编写的程序工作，以及可以通过重新编程来适应不同种类的制造工作的需要。“多功能”这个词意味着机器人能通过编程和使用不同的末端执行机构，来完成不同的制造工作。围绕着两个关键特征所撰写的定义正在变成为制造业的专业人员接受的定义。第一个带有活动关节的手臂于1951年被研制出来，由美国原子能委员会使用。在1954年，第一个可以编程的机器人由乔治狄弗设计出来。他基于下面来两项重要技术：（1） 数字控制（NC）技术。（2） 远程操作器技术。数字控制技术提供了一种非常适合机器人的机器控制技术。它可以通过存储的程序对运动进行控制。这些程序包含机器人进行顺序运动的数据，开始运动和停止运动的时间控制信号，以及作出决定所需要的逻辑语句。远程操作器技术使得一台机器的性能超出一台数控机器。它可以使这种机器能够在不容易进入和不安全的环境中完成各种制造任务。通过融合了上述两种技术，狄弗研制出第一个机器人，它是一个不复杂的，可以编程的物料运送机器人。第一台商业化生产的机器人在1959年研制成功。通用汽车公司在1962年安装了第一台用于生产线上的工业机器人，它是尤尼梅森公司生产的。在1973年，辛辛提那米兰克朗公司研制出T-3工业机器人，在机器人的控制方面取得了较大的进展。T-3机器人是第一台商业化生产的采用计算机控制的机器人。数字控制技术和远程操作器技术推动了大范围的机器人研制和应用。但是主要的技术进步并不仅仅是由于这些新的应用能力而产生的，而是必须有利用这些能力所得到的效益来提供动力。就工业机器人而言，这个动力是经济性。在20世纪70年代中，工资的快速增长大大增加了制造业的企业中的人工费用。与此同时，来自国外的竞争成为美国制造业所面临的严重考验。诸如日本等外国的制造厂家在广泛的应用了自动化技术之后，其工业产品，特别是汽车，在美国和世界市场中占据了日益增大的份额。通过采用包括机器人在内的各种自动化技术，从70年代开始，日本的制造厂家能够比没有采用自动化技术的美国制造厂家生产更多的和更便宜的汽车。随后，为了生存，美国制造厂家进行竞争，必须以比较低的成本，生产出更好的产品。其他的因素，注入寻找能够更好的完成带有危险性的制造工作的方式也促进了工业机器人的发展。但是，主要的理由一直是，而且现在仍然是提高生产率。机器人的一个优点是它们可以在相对于人类来说是危险的环境中工作。采用机器人进行焊接和切断工作室比由人工来完成这些工作更安全的例子。尽管机器人与工作地点的安全密切相关，它们本身也可能是危险的。应该仔细的设计和配置机器人和机器人单元，使它们不会伤害人类和其他机器。应该精确的计算出机器人的工作范围，并且在这个范围的四周清晰地标出危险区域。可以采用在地上划出红颜色的线和设置障碍物以阻止工人进入机器人的工作范围。即使有了这些预防措施，在使用机器人的场地中设置一个自动停止工作的系统仍然不失为一个好主意。机器人这个系统应该具有能够检测出是否有需要自动停止工作的要求的能力。为了保证能有一个安全的环境，应当安装容错计算机和冗余系统来保证在适当的时候停止机器人的工作。关于机器人系统的组成部分，可以从物质的观点也可以从系统的观点来讨论机器人系统的组成部分。从物质上看，我们可以将机器人分为机器人，电源系统和控制器（计算机）。机器人本身可以像人一样被分为基座，肩，肘，腕，抓持器和工具。这些术语中的大部分不需要做任何解释。因此，我们将根据信息传递的观点来描述机器人系统的组成部分。也就是，什么信息或者信号进入计算机的组成部分，这个组成部分进行何种逻辑或者算术运算，这个组成部分产生什么信息或者信号？应该认识到，同一个组成部分可以完成许多不同的信息处理工作（例如，中心计算机可以根据不同的数据进行许多不同种类的计算），这一点是很重要的。与之相似，在结构上分开的两个组成部分可以进行相同的信息操作（例如，肩部和肘部的执行机构用非常相似的方式将信息转换为运动）。注：出自机械工程专业英语
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