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外文资料The robot arm Robot is a type of mechantronics equipment which synthesizes the last research achievement of engine and precision engine, micro-electronics and computer, automation control and drive, sensor and message dispose and artificial intelligence and so on. With the development of economic and the demand for automation control, robot technology isdeveloped quickly and all types of the robots products are come into being. The practicality use of robot products not only solves the problems which are difficult to operate for human being, but also advances the industrial automation program. Modern industrial robots are true marvels of engineering. A robot the size of a person can easily carry a load over one hundred pounds and move it very quickly with a repeatability of +/-0.006 inches. Furthermore these robots can do that 24 hours a day for years on end with no failures whatsoever. Though they are reprogrammable, in many applications (particularly those in the auto industry) they are programmed once and then repeat that exact same task for years. At present, the research and development of robot involves several kinds of technology and the robot system configuration is so complex that the cost at large is high which to a certain extent limit the robot abroad use. To development economic practicality and high reliability robot system will be value to robot social application and economy development. With the rapid progress with the control economy and expanding of the modern cities, the let of sewage is increasing quickly: With the development of modern technology and the enhancement of consciousness about environment reserve, more and more people realized the importance and urgent of sewage disposal. Active bacteria method is an effective technique for sewage disposal，The lacunaris plastic is an effective basement for active bacteria adhesion for sewage disposal. The abundance requirement for lacunaris plastic makes it is a consequent for the plastic producing with automation and high productivity. Therefore, it is very necessary to design a manipulator that can automatically fulfill the plastic holding. With the analysis of the problems in the design of the plastic holding manipulator and synthesizing the robot research and development condition in recent years, a economic scheme is concluded on the basis of the analysis of mechanical configuration, transform system, drive device and control system and guided by the idea of the characteristic and complex of mechanical configuration, electronic, software and hardware. In this article, the mechanical configuration combines the character of direction coordinate and the arthrosis coordinate which can improve the stability and operation flexibility of the system. The main function of the transmission mechanism is to transmit power to implement department and complete the necessary movement. In this transmission structure, the screw transmission mechanism transmits the rotary motion into linear motion. Worm gear can give vary transmission ratio. Both of the transmission mechanisms have a characteristic of compact structure. The design of drive system often is limited by the environment condition and the factor of cost and technical lever. The step motor can receive digital signal directly and has the ability to response outer environment immediately and has no accumulation error, which often is used in driving system. In this driving system, open-loop control system is composed of stepping motor, which can satisfy the demand not only for control precision but also for the target of economic and practicality. On this basis，the analysis of stepping motor in power calculating and style selecting is also given. The analysis of kinematics and dynamics for object holding manipulator is given in completing the design of mechanical structure and drive system. Kinematics analysis is the basis of path programming and track control. The positive and reverse analysis of manipulator gives the relationship between manipulator space and drive space in position and speed. The relationship between manipulators tip position and arthrosis angles is concluded by coordinate transform method. The geometry method is used in solving inverse kinematics problem and the result will provide theory evidence for control system. The f0unction of dynamics is to get the relationship between the movement and force and the target is to satisfy the demand of real time control. in this chamfer, Newton-Euripides method is used in analysis dynamic problem of the cleaning robot and the arthrosis force and torque are given which provide the foundation for step motor selecting and structure dynamic optimal ting. Control system is the key and core part of the object holding manipulator system design which will direct effect the reliability and practicality of the robot system in the division of configuration and control function and also will effect or limit the development cost and cycle. With the demand of the PCL-839 card, the PC computer which has a. tight structure and is easy to be extended is used as the principal computer cell and takes the function of system initialization, data operation and dispose, step motor drive and error diagnose and so on. At the same time, the configuration structure features, task principles and the position function with high precision of the control card PCL-839 are analyzed. Hardware is the matter foundation of the control. System and the software is the spirit of the control system. The target of the software is to combine all the parts in optimizing style and to improve the efficiency and reliability of the control system. The software design of the object holding manipulator control system is divided into several blocks such as system initialization block, data process block and error station detect and dispose model and so on. PCL-839 card can solve the communication between the main computer and the control cells and take the measure of reducing the influence of the outer signal to the control system. The start and stop frequency of the step motor is far lower than the maximum running frequency. In order to improve the efficiency of the step motor, the increase and decrease of the speed is must considered when the step motor running in high speed and start or stop with great acceleration. The increase and decrease of the motors speed can be controlled by the pulse freque ncy sent to the step motor drive with a rational method. This can be implemented either by hardware or by software. A step motor shift control method is proposed, which is simple to calculate, easy to realize and the theory means is straightforward. The motor s acceleration can fit the torque-frequency curve properly with this method. And the amount of calculation load is less than the linear acceleration shift control method and the method which is based on the exponential rule to change speed. The method is tested by experiment. A t last, the research content and the achievement are sum up and the problems and shortages in main the content are also listed. The development and application of robot in the future is expected.The purpose of manipulator control is to maintain the dynamic response of a computer-based manipulator in accordance with some prespecified system performance and desired goals. In general, the dynamic performance of a manipulator directly depends on the efficiency of the control algorithms and the dynamic model of the manipulator. The control problem consists of obtaining dynamic models of the physical robot arm system and then specifying corresponding control laws or strategies to achieve the desired system response and performance.Current industrial approaches to robot arm control treat each joint of the robot arm as a simple joint servomechanism. The servomechanism approach models the varying dynamics of a manipulator inadequately because it neglects the motion and configuration of the whole arm mechanism. These changes in the parameters of the controlled system sometimes are significant enough to render conventional feedback control strategies ineffective. The result is reduced servo response speed and damping, limiting the precision and speed of the end effector and making it appropriate only for limited-precision tasks. Manipulators controlled in this manner move at slow speeds with unnecessary vibrations. Any significant performance gain in this and other areas of robot arm control require the consideration of more efficient dynamic models, sophisticated control approaches, and the use of dedicated computer architectures and parallel processing techniques. In the industrial production and other fields, people often endangered by such factors as high temperature, corrode, poisonous gas and so forth at work, which have increased labor intensity and even jeopardized the life sometimes. The corresponding problems are solved since the robot arm comes out. The robot arms can catch, put and carry objects, and its movements are flexible and diversified. It applies to medium and small-scale automated production in which production varieties can be switched. And it is widely used on soft automatic line. The robot arms are generally made by withstand high temperatures, resist corrosion of materials to adapt to the harsh environment. So they reduced the labor intensity of the workers significantly and raised work efficiency. The robot arm is an important component of industrial robots, and it can be called industrial robots on many occasions. Industrial robot is set machinery, electronics, control, computers, sensors, artificial intelligence and other advanced technologies in the integration of multidisciplinary important modern manufacturing equipment. Widely using industrial robots, not only can improve product quality and production, but also is of great significance for physical security protection, improvement of the environment for labor, reducing labor intensity, improvement of labor productivity, raw material consumption savings and lowering production costs. There are such mechanical components as ball footbridge, slides, an air control mechanical hand and so on in the design. A programmable controller, a programming device, stepping motors, stepping motors drives, direct current motors, sensor, switch power supply, an electromagnetism valve and control desk are used in electrical connection. The programmable controller output two lines pulses to stepping motors drives to drive the two stepping motors drives on beam and vertical axis; direct current motors drive the rotation of the base and the hand; sensors send signals of location to the mainframe, and the mainframe sends directive to control the extension and contraction, up and down, moves location; the mainframe send signals to control the opening and closing of the hand to carry objects. Related parameters can be changed according to request of the changes of the objects and movement flow at any time change the relevant parameters in the design, so it has great flexibility and operability.中文翻译机械手机器人是典型的机电一体化装置，它综合运用了机械与精密机械、微电子与计算机、自动控制与驱动、传感器与信息处理以及人工智能等多学科的最新研究成果，随着经济的发展和各行各业对自动化程度要求的提高，机器人技术得到了迅速发展，出现了各种各样的机器人产品。现代工业机器人是人类真正的奇迹工程。一个像人那么大的机器人可以轻松地抬起超过一百磅并可以在误差+-0.006英寸误差范围内重复的移动。更重要的是这些机器人可以每天24小时永不停止地工作。在许多应用中（特别是在自动工业中）他们是通过编程控制的，但是他们一旦编程一次，他们可以重复地做同一工作许多年。机器人产品的实用化，既解决了许多单靠人力难以解决的实际问题，又促进了工业自动化的进程。 目前，由于机器人的研制和开发涉及多方面的技术，系统结构复杂，开发和研制的成本普遍较高，在某种程度上限制了该项技术的广泛应用，因此，研制经济型、实用化、高可靠性机器人系统具有广泛的社会现实意义和经济价值。 由于我国经济建设和城市化的快速发展，城市污水排放量增长很快，污水处理己经摆在了人们的议事日程上来。随着科学技术的发展和人类知识水平的提高，人们越来越认识到污水处理的重要性和迫切性，科学家和研究人员发现塑料制品在水中是用于污水处理的很有效的污泥菌群的附着体。塑料制品的大量需求，使得塑料制品生产的自动化和高效率要求成为经济发展的必然。 本文结合塑料一次挤出成型机和塑料抓取机械手的研制过程中出现的问题，综述近儿年机器人技术研究和发展的状况，在充分发挥机、电、软、硬件各自特点和优势互补的基础上，对物料抓取机械手整体机械结构、传动系统、驱动装置和控制系统进行了分析和设计，提出了一套经济型设计方案。采用直角坐标和关节坐标相结合的框架式机械结构形式，这种方式能够提高系统的稳定性和操作灵活性。传动装置的作用是将驱动元件的动力传递给机器人机械手相应的执行机构，以实现各种必要的运动，传动方式上采用结构紧凑、传动比大的蜗轮蜗杆传动和将旋转运动转换为直线运动的螺旋传动。机械手驱动系统的设计往往受到作业环境条件的限制，同时也要考虑价格因素的影响以及能够达到的技术水平。由于步进电机能够直接接收数字量，响应速度快而且工作可靠并无累积误差，常用作数字控制系统驱动机构的动力元件，因此，在驱动装置中采用由步进电机构成的开环控制方式，这种方式既能满足控制精度的要求，又能达到经济性、实用化目的，在此基础上，对步进电机的功率计一算及选型问题经行了分析。 在完成机械结构和驱动系统设计的基础上，对物料抓取机械手运动学和动力学进行了分析。运动学分析是路径规划和轨迹控制的基础，对操作臂进行了运动学正、逆问题的分析可以完成操作空间位置和速度向驱动空间的映射，采用齐次坐标变换法得到了操作臂末端位置和姿态随关节夹角之间的变换关系，采用几何法分析了操作臂的逆向运动学方程求解问题，对控制系统设计提供了理论依据。机器人动力学是研究物体的运动和作用力之间的关系的科学，研究的目的是为了满足是实时性控制的需要，本文采用牛顿-欧拉方法对物料抓取机械手动力学进行了分析，计算出了关节力和关节力矩，为步进电机的选型和动力学分析与结构优化提供理论依据。 控制部分是整个物料抓取机械手系统设计关键和核心，它在结构和功能上的划分和实现直接关系到机器人系统的可靠性、实用性，也影响和制约机械手系统的研制成本和开发周期。在控制主机的选用上，采用结构紧凑、扩展功能强和可靠性高的PC工业控制计算机作为主机，配以PCL-839卡主要承担系统功能初始化、数据运算与处理、步进电机驱动以及故障诊断等功能;同时对PCL-839卡的结构特点、功能原理和其高定位功能等给与了分析。硬件是整个控制系统以及极限位置功能赖以存在的物质基础，软件则是计算机控制系统的神经中枢，软件设计的目的是以最优的方式将各部分功能有机的结合起来，使系统具有较高的运行效率和较强的可靠性。在物料抓取机械手软件的设计上，采用的是模块化结构，分为系统初始化模块、数据处理模块和故障状态检测与处理等几部分。主控计算机和各控制单元之间全部由PCL-839卡联系，并且由该卡实现抗干扰等问题，减少外部信号对系统的影响。 步进电机的启停频率远远小于其最高运行频率，为了提高工作效率，需要步进电机高速运行并快速启停时，必须考虑它的升，降速控制问题。电机的升降速控制可以归结为以某种合理的力一式控制发送到步进电机驱动器的脉冲频率，这可由硬件实现，也可由软件方法来实现。本文提出了一种算法简单、易于实现、理论意义明确的步进电机变速控制策略:定时器常量修改变速控制方案。该方法能使步进电机加速度与其力矩频率曲线较好地拟合，从而提高变速效率。而且它的计算量比线性加速度变速和基于指数规律加速度的变速控制小得多。通过实验证明了该方法的有效性。 最后，对论文主要研究内容和取得的技术成果进行了总结，提出了存在的问题和不足，同时对机器人技术的发展和应用进行了展望。 研究机械手控制的目的是保持以计算机为基础的机械手的动态响应，以便与一些预先设定的系统性能和理想目标保持一致。一般情况下，机械手的动态性能直接依赖于控制算法的效率和机械手的动态模型。控制问题包括获得自然的机械手系统的动态模型，然后指定相应的控制规则或步骤以达到想要的系统响应和性能。目前的工业机械臂控制将每一个机械臂的联合看做一个简单的联合伺服。伺服方法不能充分地模仿不同的动力学机械手，因为它忽略了机械手整体的运动和配置。这些控制系统的参数的变化有时是足够重要，以至于使常规的反馈控制方法失效。其结果是减少了伺服响应的速度和阻尼，限制了精度和最终效应的速度，使系统仅适用于有限精度的工作。机械手以这种方式控制速度降低而没有不必要的震动。任何在这一领域和其它领域的机械臂性能增益要求更有效率的动态模型、精密的控制方法、专门的计算机架构和并行处理技术。 在工业生产和其他领域内，由于工作的需要，人们经常受到高温、腐蚀及有毒气体等因素的危害，增加了工人的劳动强度，甚至于危及生命。自从机械手问世以来，相应的各种难题迎刃而解。机械手可在空间抓、放、搬运物体，动作灵活多样，适用于可变换生产品种的中、小批量自动化生产，广泛应用于柔性自动线。机械手一般由耐高温，抗腐蚀的材料制成，以适应现场恶劣的环境，大大降低了工人的劳动强度，提高了工作效率。机械手是工业机器人的重要组成部分，在很多情况下它就可以称为工业机器人。工业机器人是集机械、电子、控制、计算机、传感器、人工智能等多学科先进技术于一体的现代制造业重要的自动化装备。广泛采用工业机器人，不仅可以提高产品的质量与产量，而且对保障人身安全，改善劳动环境，减轻劳动强度，提高劳动生产率，节约原材料消耗以及降低生产成本，有着十分重要的意义。 本设计所用机械部件有滚珠丝杠、滑轨、气控机械抓手等。电气方面有可编程控制器（PLC）、编程器、步进电机、步进电机驱动器、直流电机、光电传感器、开关电源、电磁阀、旋转码盘、操作台等部件。可编程控制器发出两路脉冲到步进电机驱动器，分别驱动横轴、竖轴的步进电机运转；直流电机拖动底座和手爪的旋转；接近开关、微动开关、旋转码盘将位置信号反馈给主机，由主机发出指令来实现对手臂的伸缩、上下、转动位置的控制；主机发信号到气动电磁阀，以控制手爪的张合来抓放物体。本设计可根据工件的变化及运动流程的要求随时更改相关参数，具有很大的灵活性和可操作性。
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