机械手设计英文参考文献原文翻译

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多自由度机械手毕业论文中英文资料外文翻译文献

多自由度机械手毕业论文中英文资料外文翻译文献

毕业论文中英文资料外文翻译文献专业机械设计制造及其自动化课题多自由度机械手机械设计英文原文Automated Tracking and Grasping of a Moving Object with a RoboticHand-Eye SystemAbstractMost robotic grasping tasks assume a stationary or fixed object. In this paper, we explore the requirements for tracking and grasping a moving object. The focus of our work is to achieve a high level of interaction between a real-time vision system capable of tracking moving objects in 3-D and a robot arm with gripper that can be used to pick up a moving object. There is an interest in exploring the interplay of hand-eye coordination for dynamic grasping tasks such as grasping of parts on a moving conveyor system, assembly of articulated parts, or for grasping from a mobile robotic system. Coordination between an organism's sensing modalities and motor control system is a hallmark of intelligent behavior, and we are pursuing the goal of building an integrated sensing and actuation system that can operate in dynamic as opposed to static environments.The system we have built addresses three distinct problems in robotic hand-eye coordination for grasping moving objects: fast computation of 3-D motion parameters from vision, predictive control of a moving robotic arm to track a moving object, and interception and grasping. The system is able to operate at approximately human arm movement rates, and experimental results in which a moving model train is tracked is presented, stably grasped, and picked up by the system. The algorithms we have developed that relate sensing to actuation are quite general and applicable to a variety of complex robotic tasks that require visual feedback for arm and hand control.I. INTRODUCTIONThe focus of our work is to achieve a high level of interaction between real-time vision systems capable of tracking moving objects in 3-D and a robot arm equipped with a dexterous hand that can be used to intercept, grasp, and pick up a movingobject. We are interested in exploring the interplay of hand-eye coordination for dynamic grasping tasks such as grasping of parts on a moving conveyor system, assembly of articulated parts, or for grasping from a mobile robotic system. Coordination between an organism's sensing modalities and motor control system is a hallmark of intelligent behavior, and we are pursuing the goal of building an integrated sensing and actuation system that can operate in dynamic as opposed to static environments.There has been much research in robotics over the last few years that address either visual tracking of moving objects or generalized grasping problems. However, there have been few efforts that try to link the two problems. It is quite clear that complex robotic tasks such as automated assembly will need to have integrated systems that use visual feedback to plan, execute, and monitor grasping.The system we have built addresses three distinct problems in robotic hand-eye coordination for grasping moving objects: fast computation of 3-D motion parameters from vision, predictive control of a moving robotic arm to track a moving object, and interception and grasping. The system is able to operate at approximately human arm movement rates, using visual feedback to track, intercept, stably grasp, and pick up a moving object. The algorithms we have developed that relate sensing to actuation are quite general and applicable to a variety of complex robotic tasks that require visual feedback for arm and hand control.Our work also addresses a very fundamental and limiting problem that is inherent in building integrated sensing actuation systems; integration of systems with different sampling and processing rates. Most complex robotic systems are actually amalgams of different processing devices, connected by a variety of methods. For example, our system consists of three separate computation systems: a parallel image processing computer; a host computer that filters, triangulates, and predicts 3-D position from the raw vision data; and a separate arm control system computer that performs inverse kinematic transformations and joint-level servicing. Each of these systems has its own sampling rate, noise characteristics, and processing delays, which need to be integrated to achieve smooth and stable real-time performance. In our case, this involves overcoming visual processing noise and delays with a predictive filter basedupon a probabilistic analysis of the system noise characteristics. In addition, real-time arm control needs to be able to operate at fast servo rates regardless of whether new predictions of object position are available.The system consists of two fixed cameras that can image a scene containing a moving object (Fig. 1). A PUMA-560 with a parallel jaw gripper attached is used to track and pick up the object as it moves (Fig. 2). The system operates as follows:1) The imaging system performs a stereoscopic optic-flow calculation at each pixel in the image. From these optic-flow fields, a motion energy profile is obtained that forms the basis for a triangulation that can recover the 3-D position of a moving object at video rates.2) The 3-D position of the moving object computed by step 1 is initially smoothed to remove sensor noise, and a nonlinear filter is used to recover the correct trajectory parameters which can be used for forward prediction, and the updated position is sent to the trajectory-planner/arm-control system.3) The trajectory planner updates the joint-level servos of the arm via kinematic transform equations. An additional fixed-gain filter is used to provide servo-level control in case of missed or delayed communication from the vision and filtering system.4) Once tracking is stable, the system commands the arm to intercept the moving object and the hand is used to grasp the object stably and pick it up.The following sections of the paper describe each of these subsystems in detail along with experimental results.П. PREVIOUS WORKPrevious efforts in the areas of motion tracking and real-time control are too numerous to exhaustively list here. We instead list some notable efforts that have inspired us to use similar approaches. Burt et al. [9] have focused on high-speed feature detection and hierarchical scaling of images in order to meet the real-time demands of surveillance and other robotic applications. Related work has been reported by. Lee and Wohn [29] and Wiklund and Granlund [43] who uses image differencing methods to track motion. Corke, Paul, and Wohn [13] report afeature-based tracking method that uses special-purpose hardware to drive a servocontroller of an arm-mounted camera. Goldenberg et al. [16] have developed a method that uses temporal filtering with vision hardware similar to our own. Luo, Mullen, and Wessel [30] report a real-time implementation of motion tracking in 1-D based on Horn and Schunk’s method. Vergheseetul. [41] Report real-time short-range visual tracking of objects using a pipelined system similar to our own. Safadi [37] uses a tracking filter similar to our own and a pyramid-based vision system, but few results are reported with this system. Rao and Durrant-Whyte [36] have implemented a Kalman filter-based decentralized tracking system that tracks moving objects with multiple cameras. Miller [31] has integrated a camera and arm for a tracking task where the emphasis is on learning kinematic and control parameters of the system. Weiss et al. [42] also use visual feedback to develop control laws for manipulation. Brown [8] has implemented a gaze control system that links a robotic “head” containing binocular cameras with a servo controller that allows one to maintain a fixed gaze on a moving object. Clark and Ferrier [12] also have implemented a gaze control system for a mobile robot. A variation of the tracking problems is the case of moving cameras. Some of the papers addressing this interesting problem are [9], [15], [44], and [18].The majority of literature on the control problems encountered in motion tracking experiments is concerned with the problem of generating smooth, up-to-date trajectories from noisy and delayed outputs from different vision algorithms.Our previous work [4] coped with that problem in a similar way as in [38], using an cy- p - y filter, which is a form of steady-state Kalman filter. Other approaches can be found in papers by [33], [34], [28], [6]. In the work of Papanikolopoulos et al. [33], [34], visual sensors are used in the feedback loop to perform adaptive robotic visual tracking. Sophisticated control schemes are described which combine a Kalman filter’s estimation and filtering power with an optimal (LQG) controller which computes the robot’s motion. The vision system uses an optic-flow computation based on the SSD (sum of squared differences) method which, while time consuming, appears to be accurate enough for the tracking task. Efficient use of windows in the image can improve the performance of this method. The authors have presented good tracking results, as well as stated that the controller is robust enough so the use ofmore complex (time-varying LQG) methods is not justified. Experimental results with the CMU Direct Drive Arm П show that the methods are quite accurate, robust, and promising.The work of Lee and Kay [28] addresses the problem of uncertainty of cameras in the robot’s coordinate frame. The fact that cameras have to be strictly fixed in robot’s frame might be quite annoying since each time they are (most often incidentally) displaced; one has to undertake a tedious job of their recalibration. Again, the estimation of the moving object’s position and orientation is done in the Cartesian space and a simple error model is assumed. Andersen et al. [6] adopt a 3rd-order Kalman filter in order to allow a robotic system (consisting of two degrees of freedom) to play the labyrinth game. A somewhat different approach has been explored in the work of Houshangi [24] and Koivo et al. [27]. In these works, the autoregressive (AR) and auto grassier moving-average with exogenous input (ARMAX) models are investigated for visual tracking.Ш. VISION SYSTEMIn a visual tracking problem, motion in the imaging system has to be translated into 3-D scene motion. Our approach is to initially compute local optic-flow fields that measure image velocity at each pixel in the image. A variety of techniques for computing optic-flow fields have been used with varying results includingmatching-based techniques [5], [ 10], [39], gradient-based techniques [23], [32], [ 113, and patio-temporal, energy methods [20], [2]. Optic-flow was chosen as the primitive upon which to base the tracking algorithm for the following reasons.·The ability to track an object in three dimensions implies that there will be motion across the retinas (image planes) that are imaging the scene. By identifying this motion in each camera, we can begin to find the actual 3-D motion.·The principal constraint in the imaging process is high computational speed to satisfy the update process for the robotic arm parameters. Hence, we needed to be able to compute image motion quickly and robustly. The Hom-Schunck optic-flow algorithm (described below) is well suited for real-time computation on our PIPE image processing engine.·We have developed a new framework for computing optic-flow robustly using anestimation-theoretic framework [40]. While this work does not specifically use these ideas, we have future plans to try to adapt this algorithm to such a framework.Our method begins with an implementation of the Horn-Schunck method of computing optic-flow [22]. The underlying assumption of this method is theoptic-flow constraint equation, which assumes image irradiance at time t and t+σt will be the same:If we expand this constraint via a Taylor series expansion, and drop second- and higher-order terms, we obtain the form of the constraint we need to compute normal velocity:Where u and U are the velocities in image space, and Ix, Iy,and It are the spatial and temporal derivatives in the image. This constraint limits the velocity field in an image to lie on a straight line in velocity space. The actual velocity cannot be determined directly from this constraint due to the aperture problem, but one can recover the component of velocity normal to this constraint lineA second, iterative process is usually employed to propagate velocities in image neighborhoods, based upon a variety of smoothness and heuristic constraints. These added neighborhood constraints allow for recovery of the actual velocities u,v in the image. While computationally appealing, this method of determining optic-flow has some inherent problems. First, the computation is done on a pixel-by-pixel basis, creating a large computational demand. Second, the information on optic flow is only available in areas where the gradients defined above exist.We have overcome the first of these problems by using the PIPE image processor [26], [7]. The PIPE is a pipelined parallel image processing computer capable of processing 256 x 256 x 8 bit images at frame rate speeds, and it supports the operations necessary for optic-flow computation in a pixel parallel method (a typical image operation such as convolution, warping, addition subtraction of images can be done in one cycle-l/60 s).The second problem is alleviated by our not needing to know the actual velocities in the image. What we need is the ability to locate and quantify gross image motion robustly. This rules out simple differencing methodswhich are too prone to noise and will make location of image movement difficult. Hence, a set of normal velocities at strong gradients is adequate for our task, precluding the need to iteratively propagate velocities in the image.A. Computing Normal Optic-Flow in Real-TimeOur goal is to track a single moving object in real time. We are using two fixed cameras that image the scene and need to report motion in 3-D to a robotic arm control program. Each camera is calibrated with the 3-D scene, but there is no explicit need to use registered (i.e., scan-line coherence) cameras. Our method computes the normal component of optic-flow for each pixel in each camera image, finds a centurion of motion energy for each image, and then uses triangulation to intersect the back-projected centurions of image motion in each camera. Four processors are used in parallel on the PIPE. The processors are assigned as four per camera-two each for the calculation of X and Y motion energy centurions in each image. We also use a special processor board (ISMAP) to perform real-time histogram. The steps below correspond to the numbers in Fig. 3.1) The camera images the scene and the image is sent to processing stages in the PIPE.2) The image is smoothed by convolution with a Gaussian mask. The convolution operator is a built-in operation in the PIPE and it can be performed in one frame cycle. 3-4) In the next two cycles, two more images are read in, smoothed and buffered, yielding smoothed images Io and I1 and I2.The ability to buffer and pipeline images allows temporal operations on images, albeit at the cost of processing delays (lags) on output. There are now three smoothed images in the PIPE, with the oldest image lagging by 3/60 s.5) Images Io and I2, are subtracted yielding the temporal derivative It.6) In parallel with step 5, image I1is convolved with a 3 x 3 horizontal spatial gradient operator, returning the discrete form of I,. In parallel, the vertical spatial gradient is calculated yielding I, (not shown).7-8)The results from steps 5 and 6 are held in buffers and then are input to alook-up table that divides the temporal gradient at each pixel by the absolute value of the summed horizontal and vertical spatial gradients [which approximates thedenominator in (3)]. This yields the normal velocity in the image at each pixel. These velocities are then threshold and any isolated (i.e., single pixel motion energy) blobs are morphologically eroded. The above threshold velocities are then encoded as gray value 255. In our experiments, we threshold all velocities below 10 pixels per 60 ms to zero velocity.9-10) In order to get the centurion of the motion information, we need the X and Y coordinates of the motion energy. For simplicity, we show only the situation for the X coordinate. The gray-value ramp in Fig. 3 is an image that encodes the horizontal coordinate value (0-255) for each point in the image as a gray value.Thus, it is an image that is black (0) at horizontal pixel 0 and white (255) at horizontal pixel 255. If we logically and each pixel of the above threshold velocity image with the ramp image, we have an image which encodes high velocity pixels with their positional coordinates in the image, and leaves pixels with no motion at zero.11) By taking this result and histogram it, via a special stage of the PIPE which performs histograms at frame rate speeds, we can find the centurion of the moving object by finding the mean of the resulting histogram. Histogram the high-velocity position encoded images yields 256 16-bit values (a result for each intensity in the image). These 256 values can be read off the PIPE via a parallel interface in about 10 ms. This operation is performed in parallel to find the moving object’s Y censored (and in parallel for X and Y centurions for camera 2). The total associated delay time for finding the censored of a moving object becomes 15 cycles or 0.25 s.The same algorithm is run in parallel on the PIPE for the second camera. Once the motion centurions are known for each camera, they are back-projected into the scene using the camera calibration matrices and triangulated to find the actual 3-D location of the movement. Because of the pipelined nature of the PIPE, a new X or Y coordinate is produced every 1/60 s with this delay. While we are able to derive 3-D position from motion stereo at real-time rates, there are a number of sources of noise and error inherent in the vision system. These include stereo triangulation error, moving shadow s which are interpreted as object motion (we use no special lighting in the scene), and small shifts in censored alignments due to the different viewing angles of the cameras, which have a large baseline. The net effect of this is to create a 3-Dposition signal that is accurate enough for gross-level object tracking, but is not sufficient for the smooth and highly accurate tracking required for grasping the object.英文翻译自动跟踪和捕捉系统中的机械手系统摘要——许多机器人抓捕任务都被假设在了一个固定的物体上进行。

机械手外文文献和文献翻译

机械手外文文献和文献翻译

This is a application of Application Ser. No. 10/799,595, filed on Mar。

15, 2004 now U.S.with light emitted from an irradiation source based on the optical mouse system or the like to form an irradiation pattern constituted by a high—luminance region and a relatively low-luminance region corresponding to the minute shape of the spherical surface. Movement information is then obtained by using the movement of the irradiation pattern based on the relative movement between the spherical surface and the sensor。

FIG. 1 is a view which is most indicative of the main part of this embodiment。

Reference numerals 20—1, 20—2,and 20—3 denote the first,second,and third elastic member vibration elements of a multiple degree-of—freedom vibration actuator,respectively; and 1—1 and 1-2,piezoelectric ceramics which generate bending vibrations and longitudinal vibrations,respectively. Each vibration element 20 is fixed/supported on a frame (not shown) with an arm portion (see 1#x2013;2#x2032;in FIG。

机械手臂外文文献翻译、中英文翻译、外文翻译

机械手臂外文文献翻译、中英文翻译、外文翻译

外文出处:《Manufacturing Engineering and Technology—Machining》附件1:外文原文ManipulatorRobot developed in recent decades as high-tech automated production equipment. I ndustrial robot is an important branch of industrial robots. It features can be program med to perform tasks in a variety of expectations, in both structure and performance a dvantages of their own people and machines, in particular, reflects the people's intellig ence and adaptability. The accuracy of robot operations and a variety of environments the ability to complete the work in the field of national economy and there are broad p rospects for development. With the development of industrial automation, there has be en CNC machining center, it is in reducing labor intensity, while greatly improved lab or productivity. However, the upper and lower common in CNC machining processes material, usually still use manual or traditional relay-controlled semi-automatic device . The former time-consuming and labor intensive, inefficient; the latter due to design c omplexity, require more relays, wiring complexity, vulnerability to body vibration inte rference, while the existence of poor reliability, fault more maintenance problems and other issues. Programmable Logic Controller PLC-controlled robot control system for materials up and down movement is simple, circuit design is reasonable, with a stron g anti-jamming capability, ensuring the system's reliability, reduced maintenance rate, and improve work efficiency. Robot technology related to mechanics, mechanics, elec trical hydraulic technology, automatic control technology, sensor technology and com puter technology and other fields of science, is a cross-disciplinary integrated technol ogy.First, an overview of industrial manipulatorRobot is a kind of positioning control can be automated and can be re-programmed to change in multi-functional machine, which has multiple degrees of freedom can be used to carry an object in order to complete the work in different environments. Low wages in China, plastic products industry, although still a labor-intensive, mechanical hand use has become increasingly popular. Electronics and automotive industries thatEurope and the United States multinational companies very early in their factories in China, the introduction of automated production. But now the changes are those found in industrial-intensive South China, East China's coastal areas, local plastic processin g plants have also emerged in mechanical watches began to become increasingly inter ested in, because they have to face a high turnover rate of workers, as well as for the workers to pay work-related injuries fee challenges.With the rapid development of China's industrial production, especially the reform and opening up after the rapid increase in the degree of automation to achieve the wor kpiece handling, steering, transmission or operation of brazing, spray gun, wrenches a nd other tools for processing and assembly operations since, which has more and mor e attracted our attention. Robot is to imitate the manual part of the action, according to a given program, track and requirements for automatic capture, handling or operation of the automatic mechanical devices.In real life, you will find this a problem. In the machine shop, the processing of part s loading time is not annoying, and labor productivity is not high, the cost of producti on major, and sometimes man-made incidents will occur, resulting in processing were injured. Think about what could replace it with the processing time of a tour as long a s there are a few people, and can operate 24 hours saturated human right? The answer is yes, but the robot can come to replace it.Production of mechanical hand can increase the automation level of production and labor productivity; can reduce labor intensity, ensuring product quality, to achieve saf e production; particularly in the high-temperature, high pressure, low temperature, lo w pressure, dust, explosive, toxic and radioactive gases such as poor environment can replace the normal working people. Here I would like to think of designing a robot to be used in actual production.Why would a robot designed to provide a pneumatic power: pneumatic robot refers to the compressed air as power source-driven robot. With pressure-driven and other en ergy-driven comparison have the following advantages: 1. Air inexhaustible, used late r discharged into the atmosphere, does not require recycling and disposal, do not pollu te the environment. (Concept of environmental protection) 2. Air stick is small, the pipeline pressure loss is small (typically less than asphalt gas path pressure drop of one-thousandth), to facilitate long-distance transport. 3. Compressed air of the working pre ssure is low (usually 4 to 8 kg / per square centimeter), and therefore moving the mate rial components and manufacturing accuracy requirements can be lowered. 4. With th e hydraulic transmission, compared to its faster action and reaction, which is one of th e advantages pneumatic outstanding. 5. The air cleaner media, it will not degenerate, n ot easy to plug the pipeline. But there are also places where it fly in the ointment: 1. A s the compressibility of air, resulting in poor aerodynamic stability of the work, resulti ng in the implementing agencies as the precision of the velocity and not easily control led. 2. As the use of low atmospheric pressure, the output power can not be too large; i n order to increase the output power is bound to the structure of the entire pneumatic s ystem size increased.With pneumatic drive and compare with other energy sources drive has the followin g advantages:Air inexhaustible, used later discharged into the atmosphere, without recycling and disposal, do not pollute the environment. Accidental or a small amount of leakage wo uld not be a serious impact on production. Viscosity of air is small, the pipeline pressu re loss also is very small, easy long-distance transport.The lower working pressure of compressed air, pneumatic components and therefor e the material and manufacturing accuracy requirements can be lowered. In general, re ciprocating thrust in 1 to 2 tons pneumatic economy is better.Compared with the hydraulic transmission, and its faster action and reaction, which is one of the outstanding merits of pneumatic.Clean air medium, it will not degenerate, not easy to plug the pipeline. It can be saf ely used in flammable, explosive and the dust big occasions. Also easy to realize auto matic overload protection.Second, the composition, mechanical handRobot in the form of a variety of forms, some relatively simple, some more complic ated, but the basic form is the same as the composition of the , Usually by the implem enting agencies, transmission systems, control systems and auxiliary devices composed.1.Implementing agenciesManipulator executing agency by the hands, wrists, arms, pillars. Hands are crawlin g institutions, is used to clamp and release the workpiece, and similar to human finger s, to complete the staffing of similar actions. Wrist and fingers and the arm connecting the components can be up and down, left, and rotary movement. A simple mechanical hand can not wrist. Pillars used to support the arm can also be made mobile as needed .2. TransmissionThe actuator to be achieved by the transmission system. Sub-transmission system c ommonly used manipulator mechanical transmission, hydraulic transmission, pneuma tic and electric power transmission and other drive several forms.3. Control SystemManipulator control system's main role is to control the robot according to certain p rocedures, direction, position, speed of action, a simple mechanical hand is generally not set up a dedicated control system, using only trip switches, relays, control valves a nd circuits can be achieved dynamic drive system control, so that implementing agenc ies according to the requirements of action. Action will have to use complex program mable robot controller, the micro-computer control.Three, mechanical hand classification and characteristicsRobots are generally divided into three categories: the first is the general machinery does not require manual hand. It is an independent not affiliated with a particular host device. It can be programmed according to the needs of the task to complete the oper ation of the provisions. It is characterized with ordinary mechanical performance, also has general machinery, memory, intelligence ternary machinery. The second category is the need to manually do it, called the operation of aircraft. It originated in the atom, military industry, first through the operation of machines to complete a particular job, and later developed to operate using radio signals to carry out detecting machines suc h as the Moon. Used in industrial manipulator also fall into this category. The third cat egory is dedicated manipulator, the main subsidiary of the automatic machines or automatic lines, to solve the machine up and down the workpiece material and delivery. T his mechanical hand in foreign countries known as the "Mechanical Hand", which is t he host of services, from the host-driven; exception of a few outside the working proc edures are generally fixed, and therefore special.Main features:First, mechanical hand (the upper and lower material robot, assembly robot, handlin g robot, stacking robot, help robot, vacuum handling machines, vacuum suction crane, labor-saving spreader, pneumatic balancer, etc.).Second, cantilever cranes (cantilever crane, electric chain hoist crane, air balance th e hanging, etc.)Third, rail-type transport system (hanging rail, light rail, single girder cranes, doubl e-beam crane)Four, industrial machinery, application of handManipulator in the mechanization and automation of the production process develo ped a new type of device. In recent years, as electronic technology, especially comput er extensive use of robot development and production of high-tech fields has become a rapidly developed a new technology, which further promoted the development of ro bot, allowing robot to better achieved with the combination of mechanization and auto mation.Although the robot is not as flexible as staff, but it has to the continuous duplication of work and labor, I do not know fatigue, not afraid of danger, the power snatch weig ht characteristics when compared with manual large, therefore, mechanical hand has b een of great importance to many sectors, and increasingly has been applied widely, for example:(1) Machining the workpiece loading and unloading, especially in the automatic lat he, combination machine tool use is more common.(2) In the assembly operations are widely used in the electronics industry, it can be used to assemble printed circuit boards, in the machinery industry It can be used to ass emble parts and components.(3) The working conditions may be poor, monotonous, repetitive easy to sub-fatigue working environment to replace human labor.(4) May be in dangerous situations, such as military goods handling, dangerous go ods and hazardous materials removal and so on..(5) Universe and ocean development.(6), military engineering and biomedical research and testing.Help mechanical hands: also known as the balancer, balance suspended, labor-saving spreader, manual Transfer machine is a kind of weightlessness of manual load system, a novel, time-saving technology for material handling operations booster equipment, belonging to kinds of non-standard design of series products. Customer application ne eds, creating customized cases. Manual operation of a simulation of the automatic ma chinery, it can be a fixed program draws ﹑ handling objects or perform household to ols to accomplish certain specific actions. Application of robot can replace the people engaged in monotonous ﹑ repetitive or heavy manual labor, the mechanization and a utomation of production, instead of people in hazardous environments manual operati on, improving working conditions and ensure personal safety. The late 20th century, 4 0, the United States atomic energy experiments, the first use of radioactive material ha ndling robot, human robot in a safe room to manipulate various operations and experi mentation. 50 years later, manipulator and gradually extended to industrial production sector, for the temperatures, polluted areas, and loading and unloading to take place t he work piece material, but also as an auxiliary device in automatic machine tools, ma chine tools, automatic production lines and processing center applications, the comple tion of the upper and lower material, or From the library take place knife knife and so on according to fixed procedures for the replacement operation. Robot body mainly b y the hand and sports institutions. Agencies with the use of hands and operation of obj ects of different occasions, often there are clamping ﹑ support and adsorption type of care. Movement organs are generally hydraulic pneumatic ﹑﹑ electrical device dri vers. Manipulator can be achieved independently retractable ﹑ rotation and lifting m ovements, generally 2 to 3 degrees of freedom. Robots are widely used in metallurgic al industry, machinery manufacture, light industry and atomic energy sectors.Can mimic some of the staff and arm motor function, a fixd procedure for the capture, handling objects or operating tools, automatic operation device. It can replace hum an labor in order to achieve the production of heavy mechanization and automation th at can operate in hazardous environments to protect the personal safety, which is wide ly used in machinery manufacturing, metallurgy, electronics, light industry and nuclea r power sectors. Mechanical hand tools or other equipment commonly used for additio nal devices, such as the automatic machines or automatic production line handling an d transmission of the workpiece, the replacement of cutting tools in machining centers , etc. generally do not have a separate control device. Some operating devices require direct manipulation by humans; such as the atomic energy sector performs household hazardous materials used in the master-slave manipulator is also often referred to as m echanical hand.Manipulator mainly by hand and sports institutions. Task of hand is holding the wor kpiece (or tool) components, according to grasping objects by shape, size, weight, mat erial and operational requirements of a variety of structural forms, such as clamp type, type and adsorption-based care such as holding. Sports organizations, so that the com pletion of a variety of hand rotation (swing), mobile or compound movements to achie ve the required action, to change the location of objects by grasping and posture. Robot is the automated production of a kind used in the process of crawling and mo ving piece features automatic device, which is mechanized and automated production process developed a new type of device. In recent years, as electronic technology, esp ecially computer extensive use of robot development and production of high-tech fiel ds has become a rapidly developed a new technology, which further promoted the dev elopment of robot, allowing robot to better achieved with the combination of mechani zation and automation. Robot can replace humans completed the risk of duplication of boring work, to reduce human labor intensity and improve labor productivity. Manipu lator has been applied more and more widely, in the machinery industry, it can be use d for parts assembly, work piece handling, loading and unloading, particularly in the a utomation of CNC machine tools, modular machine tools more commonly used. At pr esent, the robot has developed into a FMS flexible manufacturing systems and flexibl e manufacturing cell in an important component of the FMC. The machine tool equipment and machinery in hand together constitute a flexible manufacturing system or a f lexible manufacturing cell, it was adapted to small and medium volume production, y ou can save a huge amount of the work piece conveyor device, compact, and adaptabl e. When the work piece changes, flexible production system is very easy to change wi ll help enterprises to continuously update the marketable variety, improve product qua lity, and better adapt to market competition. At present, China's industrial robot techno logy and its engineering application level and comparable to foreign countries there is a certain distance, application and industrialization of the size of the low level of robo t research and development of a direct impact on raising the level of automation in Ch ina, from the economy, technical considerations are very necessary. Therefore, the stu dy of mechanical hand design is very meaningful.附件1:外文资料翻译译文机械手机械手是近几十年发展起来的一种高科技自动化生产设备。

外文翻译--工业机械手-精品

外文翻译--工业机械手-精品

本科毕业论文(设计)相关中英文翻译资料资料题目:工业机械手设计学生姓名:所在院系:机电学院所学专业:机电技术教育完成时间:Industry manipulatorThe industry manipulator is one kind of high tech automation production equipment which the nearly several dozens years develop, the industry manipulator is an industry robot important branch, its characteristic is may complete each kind of anticipated work task through the programming, has at the same time the human and the machine respective merit in the structure and the performance, has manifested human's intelligence and the compatibility especially, in the manipulator work accuracy and each kind of environment completes the work ability, has the broad prospects for development in the national economy various domains, along with the industrial automation development, appeared the numerical control processing center, it while reduces worker's labor intensity, enhanced the labor productivity greatly, butIn numerical control processing common on yummy treats working procedure, usually still used the manual control or the tradition black-white control semiautomatic installment, the former required a lot of work time-consuming, the efficiency is low, because the latter designed complex, had many relays, the wiring to be numerous and diverse, is vibrated easily the chassis the disturbance, but had the reliability badly, the breakdown many, questions and so on service difficulty, the programmable controller PLC control on yummy treats manipulator control system movement simple, the line design reasonable, had the strong antijamming ability, had guaranteed the system movement reliability, reduced the service rate, enhanced the working efficiency.The manipulator technology involves to mechanics, mechanics, the electrical hydraulic pressure technology, the automatic control technology, the sensor technology and the computer technology and so on, is an interdisciplinary comprehensive technology.The manipulator is one kind can automate the localization control and may program the multi-purpose machines which the foreword changes, it has many degrees of freedom, available transports the object to complete in each different environment works.In wage level low China, plastic product profession although still belonged to the labor force intensity, manipulator's use already more and more popularized, these electronic and automobile industry European and American Multinational corporation was very early on is located in China's factory in them to introduce the automated production, but the present change was these distributes in industry crowded South China, East China coastal area Chinese Native place Plastic Processing factory also starts to the mechanical wristwatch to appear the more and more strong interest, because they had to face the worker rate of personnel loss to be high, as well as the halving belt came challenge.Along with our country industrial production leap development, the automaticity rapid enhancement, realization work piece loading and unloading, welding torch, spray gun, trigger tools and so on changes, the transportation or manages carries on work and so on processing, assembly automations, has brought to people's attention increasingly, simultaneously also requests the feeder construction to be more nimble, the flexibility, adapts for delivers the different goods, this enables for the feeding manipulator in the automaton, to obtain the increasingly widespread application from the generatrix in.In the production may enhance the production using the manipulator the automated level and the labor productivity, may reduce the labor intensity, the guarantee product quality, the realization safety in production, the industry manipulator can replace the human in the industrial production to make certain monotonous, frequent and the redundant long time work, perhaps dangerous, under adverse circumstance work, for example in the ramming, the pressure casting, the heat treatment, the welding, the painting, plastic working procedures and so on in product forming, machine-finishing and simple assembly, as well as in departments and so on in atomic-energy industry, completes to the human body harmful material transportingor the craft operation, as well as aspects and so on light industry, transportation shipping industry obtain the more and more widespread application.工业机械手工业机械手是近几十年发展起来的一种高科技自动化生产设备,工业机械手是工业机器人的一个重要分支,它的特点是可通过编程来完成各种预期的作业任务,在构造和性能上兼有人和机器各自的优点,尤其体现了人的智能和适应性,机械手作业的准确性和各种环境中完成作业的能力,在国民经济各领域有着广阔的发展前景,随着工业自动化的发展,出现了数控加工中心,它在减轻工人的劳动强度的同时,大大提高了劳动生产率,但数控加工中常见的上下料工序,通常仍采用人工操作或传统继电器控制的半自动化装置,前者费时费工、效率低,后者因设计复杂,需较多继电器,接线繁杂,易受车体振动干扰,而存在可靠性差、故障多、维修困难等问题,可编程序控制器PLC控制的上下料机械手控制系统动作简便、线路设计合理、具有较强的抗干扰能力,保证了系统运行的可靠性,降低了维修率,提高了工作效率。

工业机器人中英文翻译、外文文献翻译、外文翻译

工业机器人中英文翻译、外文文献翻译、外文翻译

工业机器人中英文翻译、外文文献翻译、外文翻译外文原文:RobotAfter more than 40 years of development, since its first appearance till now, the robot has already been widely applied in every industrial fields, and it has become the important standard of industry modernization.Robotics is the comprehensive technologies that combine with mechanics, electronics, informatics and automatic control theory. The level of the robotic technology has already been regarded as the standard of weighing a national modern electronic-mechanical manufacturing technology.Over the past two decades, the robot has been introduced into industry to perform many monotonous and often unsafe operations. Because robots can perform certain basic more quickly and accurately than humans, they are being increasingly used in various manufacturing industries.With the maturation and broad application of net technology, the remote control technology of robot based on net becomes more and more popular in modern society. It employs the net resources in modern society which are already three to implement the operatio of robot over distance. It also creates many of new fields, such as remote experiment, remote surgery, and remote amusement. What's more, in industry, it can have a beneficial impact upon the conversion of manufacturing means.The key words are reprogrammable and multipurpose because most single-purpose machines do not meet these two requirements. 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 manufacturing tasks. The term “multipurpose” means that the robot can perform many different functions, depending on the program and tooling currently in use.Developed from actuating mechanism, industrial robot can imitation some actions and functions of human being, which can be used to moving all kinds of material components tools and so on, executing mission by execuatable program multifunctionmanipulator. It is extensive used in industry and agriculture production, astronavigation and military engineering.During the practical application of the industrial robot, the working efficiency and quality are important index of weighing the performance of the robot. It becomes key problems which need solving badly to raise the working efficiencies and reduce errors of industrial robot in operating actually. Time-optimal trajectory planning of robot is that optimize the path of robot according to performance guideline of minimum time of robot under all kinds of physical constraints, which can make the motion time of robot hand minimum between two points or along the special path. The purpose and practical meaning of this research lie enhance the work efficiency of robot.Due to its important role in theory and application, the motion planning of industrial robot has been given enough attention by researchers in the world. Many researchers have been investigated on the path planning for various objectives such as minimum time, minimum energy, and obstacle avoidance.The basic terminology of robotic systems is introduced in the following:A robot is a reprogrammable, multifunctional manipulator designed to move parts, materials, tools, or special devices through variable programmed motions for the performance of a variety of different task. This basic definition leads to other definitions, presented in the following paragraphs that give a complete picture of a robotic system.Preprogrammed locations are paths that the robot must follow to accomplish work. At some of these locations, the robot will stop and perform some operation, such as assembly of parts, spray painting, or welding. These preprogrammed locations are stored in the robot’s memory and are recalled later for continuous operation. Furthermore, these preprogrammed locations, as well as other programming feature, an industrial robot is very much like a computer, where data can be stored and later recalled and edited.The manipulator is the arm of the robot. It allows the robot to bend, reach, and twist. This movement is provided by the manipulator’s axes, also called the degrees of freedom of the robot. A robot can have from 3 to 16 axes. The term degrees of freedom will always relate to the number of axes found on a robot.The tooling and grippers are not part of the robotic system itself: rather, they areattachments that fit on the end of the robot’s arm. These attachments connected to the end of the robot’s arm allow the robot to lift parts, spot-weld, paint, arc-well, drill, deburr, and do a variety of tasks, depending on what is required of the robot.The robotic system can also control the work cell of the operating robot. The work cell of the robot is the total environment in which the robot must perform its task. Included within this cell may be the controller, the robot manipulator, a work table, safety features, or a conveyor. All the equipment that is required in order for the robot to do its job is included in the work cell. In addition, signals from outside devices can communicate with the robot in order to tell the robot when it should assemble parts, pick up parts, or unload parts to a conveyor.The robotic system has three basic components: the manipulator, the controller, and the power source.ManipulatorThe manipulator, which dose the physical work of the robotic system, consists of two sections: the mechanical section and the attached appendage. The manipulator also has a base to which the appendages are attached.The base of the manipulator is usually fixed to the floor of the work area. Sometimes, though, the base may be movable. In this case, the base is attached to either a rail or a track, allowing the manipulator to be moved from one location to anther.As mentioned previously, the appendage extends from the base of the robot. The appendage is the arm of the robot. It can be either a straight, movable arm or a jointed arm. The jointed arm is also known as an articulated arm.The appendages of the robot manipulator give the manipulator its various axes of motion. These axes are attached to a fixed base, which, in turn, is secured to a mounting. This mounting ensures that the manipulator will remain in one location.At the end of the arm, a wrist is connected. The wrist is made up of additional axes and a wrist flange. The wrist flange allows the robot user to connect different tooling to the wrist for different jobs.The manipulator’s axes allow it to perform work within a certain area. This area is called the work cell of the robot, and its size corresponds to the size of the manipulator. As the robot’s physical size increases, the size of the work cell must also increase.The movement of the manipulator is controlled by actuators, or drive system. The actuator, or drive system, allows the various axes to move within the work cell. The drive system can use electric, hydraulic, or pneumatic power. The energy developed by the drive system is converted to mechanical power by various mechanical drive systems. The drive systems are coupled through mechanical linkages. These linkages, in turn, drive the different axes of the robot. The mechanical linkages may be composed of chains, gears, and ball screws.ControllerThe controller in the robotic system is the heart of the operation. The controller stores preprogrammed information for later recall, controls peripheral devices, and communicates with computers within the plant for constant updates in production.The controller is used to control the robot manipulator’s movements as well as to control peripheral components within the work cell. The user can program the movements of the manipulator into the controller through the use of a hand-held teach pendant. This information is stored in the memory of the controller for later recall. The controller stores all program data for the robotic system. It can store several different programs, and any of these programs can be edited.The controller is also required to communicate with peripheral equipment within the work cell. For example, the controller has an input line that identifies when a machining operation is completed. When the machine cycle is completed, the input line turns on, telling the controller to position the manipulator so that it can pick up the finished part. Then, a new part is picked up by the manipulator and placed into the machine. Next, the controller signals the machine to start operation.The controller can be made from mechanically operated drums that step through a sequence of events. This type of controller operates with a very simple robotic system. The controllers found on the majority of robotic systems are more complex devices and represent state-of-the-art electronics. This is, they are microprocessor-operated. These microprocessors are either 8-bit, 16-bit, or 32-bit processors. This power allows the controller to the very flexible in its operation.The controller can send electric signals over communication lines that allow it to talk with the various axes of the manipulator. This two-way communication between therobot manipulator and the controller maintains a constant update of the location and the operation of the system. The controller also controls any tooling placed on the end of the robot’s wrist.The controller also has the job of communicating with the different plant computers. The communication link establishes the robot as part of a computer-assisted manufacturing (CAM) system.As the basic definition stated, the robot is a reprogrammable, multifunctional manipulator. Therefore, the controller must contain some type of memory storage. The microprocessor-based systems operate in conjunction with solid-state memory devices. These memory devices may be magnetic bubbles, random-access memory, floppy disks, or magnetic tape. Each memory storage device stores program information for later recall or for editing.Power supplyThe power supply is the unit that supplies power to the controller and the manipulator. Two types of power are delivered to the robotic system. One type of power is the AC power for operation of the controller. The other type of power is used for driving the various axes of the manipulator. For example, if the robot manipulator is controlled by hydraulic or pneumatic drives, control signals are sent to these devices, causing motion of the robot.For each robotic system, power is required to operate the manipulator. This power can be developed from either a hydraulic power source, a pneumatic power source, or an electric power source. These power sources are part of the total components of the robotic work cell.Classification of RobotsIndustrial robots vary widely in size, shape, number of axes, degrees of freedom, and design configuration. Each factor influences the dimensions of the robot’s working envelope or the volume of space within which it can move and perform its designated task. A broader classification of robots can been described as blew.Fixed and Variable-Sequence Robots. The fixed-sequence robot (also called a pick-and place robot) is programmed for a specific sequence of operations. Its movements are from point to point, and the cycle is repeated continuously. Thevariable-sequence robot can be programmed for a specific sequence of operations but can be reprogrammed to perform another sequence of operation.Playback Robot. An operator leads or walks the playback robot and its end effector through the desired path. The robot memorizes and records the path and sequence of motions and can repeat them continually without any further action or guidance by the operator.Numerically Controlled Robot. The numerically controlled robot is programmed and operated much like a numerically controlled machine. The robot is servo-controlled by digital data, and its sequence of movements can be changed with relative ease.Intelligent Robot. The intellingent robot is capable of performing some of the functions and tasks carried out by human beings. It is equipped with a variety of sensors with visual and tactile capabilities.Robot ApplicationsThe robot is a very special type of production tool; as a result, the applications in which robots are used are quite broad. These applications can be grouped into three categories: material processing, material handling and assembly.In material processing, robots use to process the raw material. For example, the robot tools could include a drill and the robot would be able to perform drilling operations on raw material.Material handling consists of the loading, unloading, and transferring of workpieces in manufacturing facilities. These operations can be performed reliably and repeatedly with robots, thereby improving quality and reducing scrap losses.Assembly is another large application area for using robotics. An automatic assembly system can incorporate automatic testing, robot automation and mechanical handling for reducing labor costs, increasing output and eliminating manual handling concerns.Hydraulic SystemThere are only three basic methods of transmitting power: electrical, mechanical, and fluid power. Most applications actually use a combination of the three methods to obtain the most efficient overall system. To properly determine which principle method to use, it is important to know the salient features of each type. For example, fluidsystems can transmit power more economically over greater distances than can mechanical type. However, fluid systems are restricted to shorter distances than are electrical systems.Hydraulic power transmission systems are concerned with the generation, modulation, and control of pressure and flow, and in general such systems include:1.Pumps which convert available power from the prime mover to hydraulicpower at the actuator.2.Valves which control the direction of pump-flow, the level of powerproduced, and the amount of fluid-flow to the actuators. The power level isdetermined by controlling both the flow and pressure level.3.Actuators which convert hydraulic power to usable mechanical power outputat the point required.4.The medium, which is a liquid, provides rigid transmission and control aswell as lubrication of components, sealing in valves, and cooling of thesystem.5.Connectors which link the various system components, provide powerconductors for the fluid under pressure, and fluid flow return totank(reservoir).6.Fluid storage and conditioning equipment which ensure sufficient quality andquantity as well as cooling of the fluid..Hydraulic systems are used in industrial applications such as stamping presses, steel mills, and general manufacturing, agricultural machines, mining industry, aviation, space technology, deep-sea exploration, transportation, marine technology, and offshore gas and petroleum exploration. In short, very few people get through a day of their lives without somehow benefiting from the technology of hydraulics.The secret of hydraulic system’s success and widespread use is its versatility and manageability. Fluid power is not hindered by the geometry of the machine as is the case in mechanical systems. Also, power can be transmitted in almost limitless quantities because fluid systems are not so limited by the physical limitations of materials as are the electrical systems. For example, the performance of an electromagnet is limited by the saturation limit of steel. On the other hand, the powerlimit of fluid systems is limited only by the strength capacity of the material.Industry is going to depend more and more on automation in order to increase productivity. This includes remote and direct control of production operations, manufacturing processes, and materials handling. Fluid power is the muscle of automation because of advantages in the following four major categories.1.Ease and accuracy of control. By the use of simple levers and push buttons,the operator of a fluid power system can readily start, stop, speed up or slowdown, and position forces which provide any desired horsepower withtolerances as precise as one ten-thousandth of an inch. Fig. shows a fluidpower system which allows an aircraft pilot to raise and lower his landinggear. When the pilot moves a small control valve in one direction, oil underpressure flows to one end of the cylinder to lower the landing gear. To retractthe landing gear, the pilot moves the valve lever in the opposite direction,allowing oil to flow into the other end of the cylinder.2.Multiplication of force. A fluid power system (without using cumbersomegears, pulleys, and levers) can multiply forces simply and efficiently from afraction of an ounce to several hundred tons of output.3.Constant force or torque. Only fluid power systems are capable of providingconstant force or torque regardless of speed changes. This is accomplishedwhether the work output moves a few inches per hour, several hundred inchesper minute, a few revolutions per hour, or thousands of revolutions perminute.4.Simplicity, safety, economy. In general, fluid power systems use fewermoving parts than comparable mechanical or electrical systems. Thus, theyare simpler to maintain and operate. This, in turn, maximizes safety,compactness, and reliability. For example, a new power steering controldesigned has made all other kinds of power systems obsolete on manyoff-highway vehicles. The steering unit consists of a manually operateddirectional control valve and meter in a single body. Because the steering unitis fully fluid-linked, mechanical linkages, universal joints, bearings, reductiongears, etc. are eliminated. This provides a simple, compact system. Inapplications. This is important where limitations of control space require asmall steering wheel and it becomes necessary to reduce operator fatigue.Additional benefits of fluid power systems include instantly reversible motion, automatic protection against overloads, and infinitely variable speed control. Fluid power systems also have the highest horsepower per weight ratio of any known power source. In spite of all these highly desirable features of fluid power, it is not a panacea for all power transmission problems. Hydraulic systems also have some drawbacks. Hydraulic oils are messy, and leakage is impossible to completely eliminate. Also, most hydraulic oils can cause fires if an oil leak occurs in an area of hot equipment.Pneumatic SystemPneumatic system use pressurized gases to transmit and control power. As the name implies, pneumatic systems typically use air (rather than some other gas ) as the fluid medium because air is a safe, low-cost, and readily available fluid. It is particularly safe in environments where an electrical spark could ignite leaks from system components.In pneumatic systems, compressors are used to compress and supply the necessary quantities of air. Compressors are typically of the piston, vane or screw type. Basically a compressor increases the pressure of a gas by reducing its volume as described by the perfect gas laws. Pneumatic systems normally use a large centralized air compressor which is considered to be an infinite air source similar to an electrical system where you merely plug into an electrical outlet for electricity. In this way, pressurized air can be piped from one source to various locations throughout an entire industrial plant. The compressed air is piped to each circuit through an air filter to remove contaminants which might harm the closely fitting parts of pneumatic components such as valve and cylinders. The air then flows through a pressure regulator which reduces the pressure to the desired level for the particular circuit application. Because air is not a good lubricant (contains about 20% oxygen), pneumatics systems required a lubricator to inject a very fine mist of oil into the air discharging from the pressure regulator. This prevents wear of the closely fitting moving parts of pneumatic components.Free air from the atmosphere contains varying amounts of moisture. This moisture can be harmful in that it can wash away lubricants and thus cause excessive wear andcorrosion. Hence, in some applications, air driers are needed to remove this undesirable moisture. Since pneumatic systems exhaust directly into the atmosphere , they are capable of generating excessive noise. Therefore, mufflers are mounted on exhaust ports of air valves and actuators to reduce noise and prevent operating personnel from possible injury resulting not only from exposure to noise but also from high-speed airborne particles.There are several reasons for considering the use of pneumatic systems instead of hydraulic systems. Liquids exhibit greater inertia than do gases. Therefore, in hydraulic systems the weight of oil is a potential problem when accelerating and decelerating and decelerating actuators and when suddenly opening and closing valves. Due to Newton’s law of motion ( force equals mass multiplied by acceleration ), the force required to accelerate oil is many times greater than that required to accelerate an equal volume of air. Liquids also exhibit greater viscosity than do gases. This results in larger frictional pressure and power losses. Also, since hydraulic systems use a fluid foreign to the atmosphere , they require special reservoirs and no-leak system designs. Pneumatic systems use air which is exhausted directly back into the surrounding environment. Generally speaking, pneumatic systems are less expensive than hydraulic systems.However, because of the compressibility of air, it is impossible to obtain precise controlled actuator velocities with pneumatic systems. Also, precise positioning control is not obtainable. While pneumatic pressures are quite low due to compressor design limitations ( less than 250 psi ), hydraulic pressures can be as high as 10,000 psi. Thus, hydraulics can be high-power systems, whereas pneumatics are confined to low-power applications. Industrial applications of pneumatic systems are growing at a rapid pace. Typical examples include stamping, drilling, hoist, punching, clamping, assembling, riveting, materials handling, and logic controlling operations.工业机器人机器人自问世以来到现在,经过了40多年的发展,已被广泛应用于各个工业领域,已成为工业现代化的重要标志。

工业机械手外文文献翻译、中英文翻译

工业机械手外文文献翻译、中英文翻译

第一章概述1. 1机械手的发展历史人类在改造自然的历史进程中,随着对材料、能源和信息这三者的认识和用,不断创造各种工具(机器),满足并推动生产力的发展。

工业社会向信息社会发展,生产的自动化,应变性要求越来越高,原有机器系统就显得庞杂而不灵活,这时人们就仿造自身的集体和功能,把控制机、动力机、传动机、工作机综合集中成一体,创造了“集成化”的机器系统——机器人。

从而引起了生产系统的巨大变革,成为“人——机器人——劳动对象”,或者“人——机器人——动力机——工作机——劳动对象”。

机器人技术从诞生到现在,虽然只有短短三十几年的历史,但是它却显示了旺盛的生命力。

近年来,世界上对于发展机器人的呼声更是有增无减,发达国家竞相争先,发展中国家急起直追。

许多先进技术国家已先后把发展机器人技术列入国家计划,进行大力研究。

我国的机器人学的研究也已经起步,并把“机器人开发研究”和柔性制造技术系统和设备开发研究等与机器人技术有关的研究课题列入国家“七五”、“八五”科技发展计划以及“八六三”高科技发展计划。

工业机械手是近代自动控制领域中出现的一项新技术,并已经成为现代机械制造生产系统中的一个重要组成部分。

这种新技术发展很快,逐渐形成一门新兴的学科——机械手工程。

1. 2机械手的发展意义机械手的迅速发展是由于它的积极作用正日益为人们所认识:其一、它能部分地代替人工操作;其二、它能按照生产工艺的要求,遵循一定的程序、时间和位置来完成工件的传送和装卸;其三、它能操作必要的机具进行焊接和装配。

从而大大地改善工人的劳动条件,显著地提高劳动生产率,加快实现工业生产机械化和自动化的步伐。

因而,受到各先进工业国家的重视,投入大量的人力物力加以研究和应用。

近年来随着工业自动化的发展机械手逐渐成为一门新兴的学科,并得到了较快的发展。

机械手广泛地应用于锻压、冲压、锻造、焊接、装配、机加、喷漆、热处理等各个行业。

特别是在笨重、高温、有毒、危险、放射性、多粉尘等恶劣的劳动环境中,机械手由于其显著的优点而受到特别重视。

机械手类毕业设计外文文献翻译

机械手类毕业设计外文文献翻译

毕业设计(论文)外文资料翻译系别:专业:班级:姓名:学号:外文出处:附件: 1. 原文; 2. 译文2013年03月附件一:A Rapidly Deployable Manipulator SystemChristiaan J.J. Paredis, H. Benjamin Brown, Pradeep K. KhoslaAbstract:A rapidly deployable manipulator system combines the flexibility of reconfigurable modular hardware with modular programming tools, allowing the user to rapidly create a manipulator which is custom-tailored for a given task. This article describes two main aspects of such a system, namely, the Reconfigurable Modular Manipulator System (RMMS)hardware and the corresponding control software.1 IntroductionRobot manipulators can be easily reprogrammed to perform different tasks, yet the range of tasks that can be performed by a manipulator is limited by mechanicalstructure.Forexample, a manipulator well-suited for precise movement across the top of a table would probably no be capable of lifting heavy objects in the vertical direction. Therefore, to perform a given task,one needs to choose a manipulator with an appropriate mechanical structure.We propose the concept of a rapidly deployable manipulator system to address the above mentioned shortcomings of fixed configuration manipulators. As is illustrated in Figure 1, a rapidly deployable manipulator system consists of software and hardware that allow the user to rapidly build and program a manipulator which is customtailored for a given task.The central building block of a rapidly deployable system is a Reconfigurable Modular Manipulator System (RMMS). The RMMS utilizes a stock of interchangeable link and joint modules of various sizes and performance specifications. One such module is shown in Figure 2. By combining these general purpose modules, a wide range of special purpose manipulators can be assembled. Recently, there has been considerable interest in the idea of modular manipulators [2, 4, 5, 7, 9, 10, 14], for research applications as well as for industrial applications. However, most of these systems lack the property of reconfigurability, which is key to the concept of rapidly deployable systems. The RMMS is particularly easy toreconfigure thanks to its integrated quick-coupling connectors described in Section 3.Effective use of the RMMS requires, Task Based Design software. This software takes as input descriptions of the task and of the available manipulator modules; it generates as output a modular assembly configuration optimally suited to perform the given task. Several different approaches have been used successfully to solve simpli-fied instances of this complicated problem.A third important building block of a rapidly deployable manipulator system is a framework for the generation of control software. To reduce the complexity of softwaregeneration for real-time sensor-based control systems, a software paradigm called software assembly has been proposed in the Advanced Manipulators Laboratory at CMU.This paradigm combines the concept of reusable and reconfigurable software components, as is supported by the Chimera real-time operating system [15], with a graphical user interface and a visual programming language, implemented in OnikaA lthough the software assembly paradigm provides thesoftware infrastructure for rapidly programming manipulator systems, it does not solve the programming problem itself. Explicit programming of sensor-based manipulator systems is cumbersome due to the extensive amount of detail which must be specified for the robot to perform the task. The software synthesis problem for sensor-based robots can be simplified dramatically, by providing robust robotic skills, that is, encapsulated strategies for accomplishing common tasks in the robots task domain [11]. Such robotic skills can then be used at the task level planning stage without having to consider any of the low-level detailsAs an example of the use of a rapidly deployable system,consider a manipulator in a nuclear environment where it must inspect material and space for radioactive contamination, or assemble and repair equipment. In such an environment, widely varied kinematic (e.g., workspace) and dynamic (e.g., speed, payload) performance is required, and these requirements may not be known a priori. Instead of preparing a large set of different manipulators to accomplish these tasks—an expensive solution—one can use a rapidly deployable manipulator system. Consider the following scenario: as soon as a specific task is identified, the task based design software determinesthe task. This optimal configuration is thenassembled from the RMMS modules by a human or, in the future, possibly by anothermanipulator. The resulting manipulator is rapidly programmed by using the software assembly paradigm and our library of robotic skills. Finally,the manipulator is deployed to perform its task.Although such a scenario is still futuristic, the development of the reconfigurable modular manipulator system, described in this paper, is a major step forward towards our goal of a rapidly deployable manipulator system.Our approach could form the basis for the next generation of autonomous manipulators, in which the traditional notion of sensor-based autonomy is extended to configuration-based autonomy. Indeed, although a deployed system can have all the sensory and planning information it needs, it may still not be able to accomplish its task because the task is beyond the system’s physical capabilities. A rapidly deployable system, on the other hand, could adapt its physical capabilities based on task specifications and, with advanced sensing, control, and planning strategies, accomplish the task autonomously.2 Design of self-contained hardware modulesIn most industrial manipulators, the controller is a separate unit housing the sensor interfaces, power amplifiers, and control processors for all the joints of the manipulator.A large number of wires is necessary to connect this control unit with the sensors, actuators and brakes located in each of the joints of the manipulator. The large number of electrical connections and the non-extensible nature of such a system layout make it infeasible for modular manipulators. The solution we propose is to distribute the control hardware to each individual module of the manipulator. These modules then become self-contained units which include sensors, an actuator, a brake, a transmission, a sensor interface, a motor amplifier, and a communication interface, as is illustrated in Figure 3. As a result, only six wires are requiredfor power distribution and data communication.2.1 Mechanical designThe goal of the RMMS project is to have a wide variety of hardware modules available. So far, we have built four kinds of modules: the manipulator base, a link module, three pivot joint modules (one of which is shown in Figure 2), and one rotate joint module. The base module and the link module have no degrees-of-freedom; the joint modules have onedegree-of-freedom each. The mechanical design of the joint modules compactly fits aDC-motor, a fail-safe brake, a tachometer, a harmonic drive and a resolver.The pivot and rotate joint modules use different outside housings to provide the right-angle or in-line configuration respectively, but are identical internally. Figure 4 shows in cross-section the internal structure of a pivot joint. Each joint module includes a DC torque motor and 100:1 harmonic-drive speed reducer, and is rated at a maximum speed of 1.5rad/s and maximum torque of 270Nm. Each module has a mass of approximately 10.7kg. A single, compact, X-type bearing connects the two joint halves and provides the needed overturning rigidity. A hollow motor shaft passes through all the rotary components, and provides achannel for passage of cabling with minimal flexing.2.2 Electronic designThe custom-designed on-board electronics are also designed according to the principle of modularity. Each RMMS module contains a motherboard which provides the basic functionality and onto which daughtercards can be stacked to add module specific functionality.The motherboard consists of a Siemens 80C166 microcontroller, 64K of ROM, 64K of RAM, an SMC COM20020 universal local area network controller with an RS-485 driver, and an RS-232 driver. The function of the motherboard is to establish communication with the host interface via an RS-485 bus and to perform the lowlevel control of the module, as is explained in more detail in Section 4. The RS-232 serial bus driver allows for simple diagnostics and software prototyping.A stacking connector permits the addition of an indefinite number of daughtercards with various functions, such as sensor interfaces, motor controllers, RAM expansion etc. In our current implementation, only modules with actuators include a daughtercard. This card contains a 16 bit resolver to digital converter, a 12 bit A/D converter to interface with the tachometer, and a 12 bit D/A converter to control the motor amplifier; we have used an ofthe-shelf motor amplifier (Galil Motion Control model SSA-8/80) to drive the DC-motor. For modules with more than one degree-of-freedom, for instance a wrist module, more than one such daughtercard can be stacked onto the same motherboard.3 Integrated quick-coupling connectorsTo make a modular manipulator be reconfigurable, it is necessary that the modules can be easily connected with each other. We have developed a quick-coupling mechanism with which a secure mechanical connection between modules can be achieved by simply turning a ring handtight; no tools are required. As shown in Figure 5, keyed flanges provide precise registration of the two modules. Turning of the locking collar on the male end produces two distinct motions: first the fingers of the locking ring rotate (with the collar) about 22.5 degrees and capture the fingers on the flanges; second, the collar rotates relative to the locking ring, while a cam mechanism forces the fingers inward to securely grip the mating flanges. A ball- transfer mechanism between the collar and locking ring automatically produces this sequence of motions.At the same time the mechanical connection is made,pneumatic and electronic connections are also established. Inside the locking ring is a modular connector that has 30 male electrical pins plus a pneumatic coupler in the middle. These correspond to matching female components on the mating connector. Sets of pins are wired in parallel to carry the 72V-25A power for motors and brakes, and 48V–6A power for the electronics. Additional pins carry signals for two RS-485 serial communication busses and four video busses. A plastic guide collar plus six alignment pins prevent damage to the connector pins and assure proper alignment. The plastic block holding the female pins can rotate in the housing to accommodate the eight different possible connection orientations (8@45 degrees). The relative orientation is automatically registered by means of an infrared LED in the female connector and eight photodetectors in the male connector.4 ARMbus communication systemEach of the modules of the RMMS communicates with a VME-based host interface over a local area network called the ARMbus; each module is a node of the network. The communication is done in a serial fashion over an RS-485 bus which runs through the length of the manipulator. We use the ARCNET protocol [1] implemented on a dedicated IC (SMC COM20020). ARCNET is a deterministic token-passing network scheme which avoids network collisions and guarantees each node its time to access the network. Blocks ofinformation called packets may be sent from any node on the network to any one of the other nodes, or to all nodes simultaneously (broadcast). Each node may send one packet each time it gets the token. The maximum network throughput is 5Mb/s.The first node of the network resides on the host interface card, as is depicted in Figure 6. In addition to a VME address decoder, this card contains essentially the same hardware one can find on a module motherboard. The communication between the VME side of the card and the ARCNET side occurs through dual-port RAM.There are two kinds of data passed over the local area network. During the manipulator initialization phase, the modules connect to the network one by one, starting at the base and ending at the end-effector. On joining the network, each module sends a data-packet to the host interface containing its serial number and its relative orientation with respect to the previous module. This information allows us to automatically determine the current manipulator configuration.During the operation phase, the host interface communicates with each of the nodes at 400Hz. The data that is exchanged depends on the control mode—centralized or distributed. In centralized control mode, the torques for all the joints are computed on the VME-based real-time processing unit (RTPU), assembled into a data-packet by the microcontroller on the host interface card and broadcast over the ARMbus to all the nodes of the network. Each node extracts its torque value from the packet and replies by sending a data-packet containing the resolver and tachometer readings. In distributed control mode, on the other hand, the host computer broadcasts the desired joint values and feed-forward torques. Locally, in each module, the control loop can then be closed at a frequency much higher than 400Hz. The modules still send sensor readings back to the host interface to be used in the computation of the subsequent feed-forward torque.5 Modular and reconfigurable control softwareThe control software for the RMMS has been developed using the Chimera real-time operating system, which supports reconfigurable and reusable software components [15]. The software components used to control the RMMS are listed in Table 1. The trjjline, dls, and grav_comp components require the knowledge of certain configuration dependent parametersof the RMMS, such as the number of degrees-of-freedom, the Denavit-Hartenberg parameters etc. During the initialization phase, the RMMS interface establishes contact with each of the hardware modules to determine automatically which modules are being used and in which order and orientation they have been assembled. For each module, a data file with a parametric model is read. By combining this information for all the modules, kinematic and dynamic models of the entire manipulator are built.After the initialization, the rmms software component operates in a distributed control mode in which the microcontrollers of each of the RMMS modules perform PID control locally at 1900Hz. The communication between the modules and the host interface is at 400Hz, which can differ from the cycle frequency of the rmms software component. Since we use a triple buffer mechanism [16] for the communication through the dual-port RAM on the ARMbus host interface, no synchronization or handshaking is necessary.Because closed form inverse kinematics do not exist for all possible RMMS configurations, we use a damped least-squares kinematic controller to do the inverse kinematics computation numerically..6 Seamless integration of simulationTo assist the user in evaluating whether an RMMS con- figuration can successfully complete a given task, we have built a simulator. The simulator is based on the TeleGrip robot simulation software from Deneb Inc., and runs on an SGI Crimson which is connected with the real-time processing unit through a Bit3 VME-to-VME adaptor, as is shown in Figure 6.A graphical user interface allows the user to assemble simulated RMMS configurations very much like assembling the real hardware. Completed configurations can be tested and programmed using the TeleGrip functions for robot devices. The configurations can also be interfaced with the Chimera real-time softwarerunning on the same RTPUs used to control the actual hardware. As a result, it is possible to evaluate not only the movements of the manipulator but also the realtime CPU usage and load balancing. Figure 7 shows an RMMS simulation compared with the actual task execution.7 SummaryWe have developed a Reconfigurable Modular Manipulator System which currently consists of six hardware modules, with a total of four degrees-of-freedom. These modules can be assembled in a large number of different configurations to tailor the kinematic and dynamic properties of the manipulator to the task at hand. The control software for the RMMS automatically adapts to the assembly configuration by building kinematic and dynamic models of the manipulator; this is totally transparent to the user. To assist the user in evaluating whether a manipulator configuration is well suited for a given task, we have also built a simulator.AcknowledgmentThis research was funded in part by DOE under grant DE-F902-89ER14042, by Sandia National Laboratories under contract AL-3020, by the Department of Electrical and Computer Engineering, and by The Robotics Institute, Carnegie Mellon University.The authors would also like to thank Randy Casciola, Mark DeLouis, Eric Hoffman, and Jim Moody for their valuable contributions to the design of the RMMS system.附件二:可迅速布置的机械手系统作者:Christiaan J.J. Paredis, H. Benjamin Brown, Pradeep K. Khosla摘要:一个迅速可部署的机械手系统,可以使再组合的标准化的硬件的灵活性用标准化的编程工具结合,允许用户迅速建立为一项规定的任务来通常地控制机械手。

码垛机械手设计外文文献翻译、中英文翻译

码垛机械手设计外文文献翻译、中英文翻译

码垛机械手设计ABOUT MODERN INDUSTRIAL MANIPULATOR 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 is developed quickly and all types of the robots products are come into being. The practicality use of robot 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 0.006inches. Furthermore these robots can do that 24hours a day for years on end with no failures whatsoever. Though they are reprogrammable, in many applications 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 he 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 abundance requirement for lacunaris plastic makes it is a consequent for 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 plasticholding manipulator and synthesizing the robot research and development conditionin 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 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.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-effecter 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 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 robot, 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, air control mechanical hand and so on in the design. A programmable controller, a programming device, stepping motors, stepping motors drives, direct current motors, sensors, switch power supply, an electromagnetism valve and control desk are used in electrical connection.关于现代工业机械手文章出处:1994-2009 China Academic Joumal Electronic Publishing House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,随着经济技术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。

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翻译人:王墨墨山东科技大学文献题目:Automated Calibration of Robot Coordinatesfor 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0.16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。

在本文中,我们针对图1中所示的可重构装配系统,提出了一种自动校准方法。

在该系统中,一个机器人工作时,另一个额外机器人可以轻松插入并开始工作。

系统中安装了两台摄像机,作为快速简单设备。

该方案是为整体装配单元而开发,在协调系统中也具有更加广泛的应用。

图1:重新配置装配系统在第2节中,将介绍一种摄像机的算法问题。

第3节研究校准。

在第4、5节中,我们讨论实验结果及其应用。

第6节为总结。

2 直接线性变换我们的校准方法是基于实体坐标的3D重建技术,这些实体正是通过直接线性代数变换方法,从摄像机图像中变换而来的[10]。

尽管很多精心制作的研究方法可以作为代替,例如蔡的那种研究方法[11],但是直接线性变换法更加简单,也能充分实现我们所需要的实验结果。

假设两个摄像头观察同一个对象,我们就可以分别用,通过每台摄像机i(i=1,2)的影像平面来表示实体的位置。

直接线性变换公式如下:式中,表示参考系中对象的位置;表示未知的直接线性变换参数。

我们把等式(1)(2)改写为u=f(x), (3)式中,。

我们可以从实体的观测结果来确定直接线性变换的参数,这些实体的坐标被称为“控制点”。

一旦直接线性变换的参数被识别,摄像机中的图像将以的形式表现出所捕获的实体3D重建坐标。

3 校准方法3.1 校准综述在本节中,我们提出我们的针对装配系统重新配置的校准方法。

通过图1中所阐释的两台摄像机,我们可以对机械手进行标记检测,而通过这一检测可以使两个机械手的基本构架得以校准。

我们在工作区内测量一个有限体积,因为对于校准每一部分体积都是必不可少的。

注意,每一个机械手都在其末端器上进行了标记。

我们打算在原有的机械手“B”的旁边安装一个新的机械手“A”。

然后,我们对A与B的基本框架之间的转化进行校准。

在基本构架内,分别用和表示A、B机械手上每一组标记的校准数据。

我们可以通过每个机械手的内部传感器(编码器)来计算和。

注意,和分别包含四组标记的坐标,这些标记通过两台摄像机捕捉。

校准程序大体概述如下:1.一名人工操作员放置好两台摄像机,以便其对机械手A和B上的标记进行观测。

2.机械手A在有限空间内独立运动,摄像机对其上的标记动作进行捕捉。

成对的被抽样标记为控制点。

3.然后机械手B在有限空间内独立移动,摄像机也对其上标记的动作进行捕捉。

成对的被抽样标记为控制点。

4.机械手之间的相互位置关系从和中计算得出。

我们的方法的显著特点:●校准程序基本是自动化的。

人工操作员只需放置好两台摄像机,不管他们在哪里都可以检测这些标记。

●摄像机的位置可以未知。

因此我们可以随机放置摄像头的位置。

●可以获得两个机械手的基础构架之间的转换。

很适合由自发的主体组成的分散系统。

●校准在有限空间内进行(我们称之为“校准空间”)。

只有在校准空间周围才能获得可靠精度,在这一空间内可以实现机器人之间的操作。

3.2 问题公式化我们将用公式来表达上述程序。

两个机器人手臂之间的校准将用于计算一个仿射变换,这一变换可以将一个参考系内的坐标转换到如下的另一个坐标系内:式中,是机械手B在机械手A的坐标系中的一组标记的坐标;表示旋转;表示转换。

我们可以把等式(4)写成通过最小化下列指数,得到h,即可实现校准:由于提供了测量的位置,在等式(6)的右边包含A的首项,表示机械手A的直接线性变换的校准误差。

包含B的第二项,表示直接线性变换的误差,以及机械手B的仿射变换。

3.3 通过迭代法进行参数识别等式(6)包含了待测量的34个参数:的11个参数,的11个参数,R的9个参数,以及p的3个参数。

尽管这34个参数中有部分是多余的(因为R有3个参数),但是所有的参数对于计算等式(6)而言都是就等价的。

在如此高维度空间内做最小化相当耗时,因此我们采用线性最小二乘法来进行迭代。

该程序如下:1.最小化计算出f。

由于等式对和是线性的,所以使用最小二乘法可计算出f的最优值。

2.用定值f最小化,从而计算出h。

由于等式对于R和p中的元素是线性的,所以使用最小二乘法可计算出h的最优值。

3.用定值h最小化J,从而计算出f。

由于等式和对和是线性的,所以使用最小二乘法可计算出f的最优值。

4.如果J值收敛于一点,就停止迭代。

否则,返回到步骤2。

注意,通过以上程序,J有可能不会收敛于总体最优值,但它却提供了一个通过微量估计达到足够精度度的最佳方法。

4 校准方面的实验结果4.1 实验装置我们建立了一个实验装置,由两套六自由度机械手和两个由如图2所示的单色电荷耦合摄像机组成。

每个机械手的手臂上都安装了一个发光二极管,用来作为校准的标记。

两台机械手都有的重复精度。

每台电荷耦合摄像机具有640*416的像素分辨率。

图2 试验设备4.2 准确度方面的结果当一个新的机器人安装好后,转换的精度取决于我们的校准方法。

摄像机的布置说明详见图3。

两个机器人依次在校准空间内移动。

注意,摄像机应放置在任何可以捕获到发光二极管标记的地方。

图3:实验中的摄像机布置(a)较大的校准空间(200[mm]维度空间)(b)较小的校准空间(100[mm]维度空间)图4:校准精度两个校准空间被用于不同尺寸的维度内:一个200mm的多维数据集和一个100mm的多维数据集。

这是为了审核空间大小对于标准误差的影响。

发光二极管标记的位置被抽样作为控制点,分布在每个维度内的2*2*2到5*5*5的坐标格网点内。

校准的准确性可用以下的误差指数来评估:(7)(8)通过校准中测得的数据进行计算,得出的和是“明显的”校准误差。

这就意味着,校准误差只有在校准进程内用坐标网格点才可以评估。

然而,由于我们需要校准空间内的相等的内插点,我们用(9)(10)来求出大量点和点的值。

因此,在机器人的实际操作中,和更接近误差。

在该实验中,我们用5*5*5的坐标网格点中的位置数据进行计算,得出和。

注意,当如图4中的时,和就分别等于和。

实验结果如图4所示。

在狭小的校准空间内,校准误差更小。

增加控制点的数量增加将减小,但会让校准时间变长。

在当前的实验中,当时,大概需要两分钟来完成校准;而当时,则大概需要十分钟。

实现精度在较大的校准空间内大约为0.33mm,在较小的校准空间内大约为0.16mm。

这些值当然要比重复精度要大得多。

前者代表“绝对精度”,被公认为是大约平均5到10倍的重复精度。

我们也将这一精度与文献的精度相比较;壮等人[12]使用协调测量仪使机械手定位精度达到0.6mm;波尼兹[9]在最大应用接触力的基础上达到了0.3mm的精度。

因此,即使我们使用的是普通摄像机,我们的方法达到的精度也相对较高。

这足以实现机器人之间的操作,例如交接一个零件(图5)。

图5:校准之后的交接实验以下方法将进一步提高校准精度:●个体机器人的校准(比如,它们的运动参数的识别);●使用更多的各项同性标记;●使用更高分辨率的摄像机。

5 自动校准的插入与生产“插入与生产”一词,是表示该功能的通用名称,该功能使制造系统[7][8]的可重构性成为可能。

作者已经编写了“插入与生产”的基本程序。

现在,我们定义一种新的程序,用我们的校准方法,在装配系统内安装一个新的机器人。

一个新的机器人的插入过程应当按照如下步骤执行:1.一名人工操作员请求允许在装配单元内安装一个新的机器人。

2.如果允许,操作员将机器人放置到装配单元内。

3.机器人向所有的现有装配机器人发布自己的信息,这些信息包括其活动空间和大体位置。

这些可以由人工操作员来完成。

4.每一个现有机器人,有可能是新机器人的友邻机器人,测量它与新的机器人之间操作的大体位置。

5.该新机器人和每一个友邻候选机器人在大体的测量位置周围执行自动校准程序,该程序如前文第三节所述。

6.执行完所有的校准之后,新的机器人进行装配操作。

以上所有的程序可以通过机器人之间的协调来完成。

插件程序完成后,包括新机器人在内的所有机器人通过协调,分别进行装配。

协调进程具体细节见[8]。

6 总结本文针对装配系统的可重构性,提出了一种自动校准的方法。

两个机器人基础构架之间的转换由两台摄像机进行校准,摄像机的放置要求精度不高。

在本文中,我们阐明了以下问题:●每一个机器人的基础构建由两台摄像机以及机器人上的发光二极管标记来校准。

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