Summary: The article is opposite above all solder the robot made brief introduction in the applied circumstance in industry, next more comprehensive introduced arc welding machine implement all sorts of welding line of the person dog method, the key discussed visual method to dog to study the current situation mediumly in welding line. Keyword: Arc welding machine implement person welding line dogs the progress of preface of research current situation as level of science and technology, people is right solder the demand of quality is higher and higher also. And when soldering artificially, because get limit of heart of technical level, fatigue degree, responsibility, physiology mix objectively of subjective element should affect, maintain the stability that welder makes and consistency more for long hard. And, because solder abominable working requirement, the person that is willing to be engaged in soldering by hand is decreasing, skilled skilled worker has the tendency of shortage more. On the other hand, the development of numerical control and electronic technology, computer technology, robot technology to solder the automation of the process offerred advantageous condition, already permeated those who solder each domains. In recent years, solder automation degree is in ceaseless addition, when 2000, the mechanization automation that Chinese solder deliver a child produces is led, by frit apply metal computation is about 30% , and of the developed country solder automation rate has achieved 65% above [1] . Solder automation production already was inevitable trend. Solder the robot is to solder the revolutionary progress of automation, it was broken through solder the traditional pattern of rigid automation, developed a kind flexible the producer type of automation [2] . Current, the arc welding machine that is used at industrial production implement the person basically is to show teach emersion robot, in process of robot arc solder, they can repeat in the high accuracy inside its work space had shown taught movement. But this also brings certain limitation, that is ability of meet an emergency very poor, to the assembly of workpiece precision asks more severe, repeatability is close friends. If solder,the condition is stabilized basically, criterion the robot can assure to solder quality. But soldering actually in the process, because the robot is versed in risk produces to avoid when making, operation personnel forbids or should not be the work area that enters a robot, make handlers cannot close quarters monitors in real time solder the process makes necessary adjustment control, should solder actually so when conditional happening changes, solder for example the workpiece in the process heats in the treatment, on size error in rigging a process and positional deviation and workpiece be out of shape the change that waits for an element can make place of contact position deviate shows taught way, such meetings are caused solder quality drops to fail even. So accurate welding line dogs is to assure to solder the key of quality, it is implementation solders the important research direction of process automation. 1 arc welding machine implement the person is soldering to use the current situation mediumly since 60 time robot since entering industrial field, development is relatively rapid. Predict from 1999-2003 year, robot of industry of world actual equipment counts quantity general by 743 1999, 000 increase to 892, 000, be in among them " the robot is regnal " Japan has 370, 000, world other area is general the actual equipment amount of industrial robot will by 340, 000 increase to 508, 000. Be in the United States, actual equipment is current the amount of industrial robot will be achieved 2003 155, 000, europe is achieved 262, 000 [3] , among them above of half the number is solder robot. Soldering is one of domains with industrial robot the most fundamental application, soldering to industrial robot as abroad the research application of the respect, our country also began to solder the research application of the robot. On the amount, according to the statistic to 2001, the whole nation is mutual solder robot 1040 (do not include harbor, bay, stage) , among them arc welding machine implement robot of over spot welding. The car is made and company of car component production solders mediumly the robot is occupied solder entirely the 76 ％ of the robot, it is our country solders the user with the mainest robot. The spot welding robot of the automobile factory is much, arc welding machine implement the person is little; And car component the factory is contrary [4] . Solder the level is in the technology of the robot to progress ceaselessly, current, solder the robot introduces drive of communication servo electric machinery entirely almost, because this kind of electric machinery does not have brush, fault rate is very low. The uses 32 generally computer in controller, it is OK to divide control robot is noumenal 5 - outside 6 axes, still can make peripheral equipment and robot coordinate linkage. Solder in the China 2004 on the conference, of Japanese An Chuan company new-style solder in technology of robot controller NX100, a controller can control 4 robots at the same time in all 36 axes (every robot has reality 6 axes, 3 exterior axes) , and use soft PLC be opposite all round device undertakes controlling. Show taught a box to also use the Windows CE operating system with powerful function. Form a complete set solders the system also has a lot of new progress, 1993 dust dark on exhibition, the company below Japanese pine rotate arc welding technology uses robot of Yu Hu solder. Because use,rotate when arc welding, welding wire can rotate with the frequency of 50HZ above, when undertaking with this kind of technology welding line dogs so, its dog precision compares what the robot often uses to swing solder (swing frequency is less than 10HZ) should many tall. This company still is at was being sold above all 1993 in control ark inside the robot that hides welder, technology of support number news report realizes the union of welder and robot. Realized the confluence of welder and robot 2004, control directly by robot controller already solder undee. Use frequency to be the inversion power source of 100KHZ, bulk is cabinet, control precision is tall. Welder and the advantage with shirt-sleeve robot basically have the movement of welder and welding torch to be able to realize synchronous accurate control, of facilitating implementation careful solder conditional control, make solder systematic miniaturization. Additional, this robot mixes machine sending silk an organic whole of robot arm make it, the movement that sends filar function to cooperate welding torch quite undertakes gyral moving making, send silk in order to assure smooth from beginning to end. 2 welding line dog the sensor arc solder that uses in the process can be divided with sensor for type of direct electric arc, contact and blame contact 3 kinds big. Can divide by working principle wait for mechanical, Electromechanical, electromagnetism, capacitance, efflux, supersonic, infra-red, photoelectricity, laser, vision, electric arc, spectrum and fiber-optic type. Divide by utility useful dog at welding line, solder the condition is controlled (frit deep, frit appears wide, frit, figuration area, solder fast, cooling rate and dry stretchy) etc distributings like temperature, behavior of plasma particle density, bath. Solder according to Japan the investigation that the technology learns to did 1994 shows, in developed country of etc of Japan, Europe, use at soldering the sensor of the process has 80% is to use those who dog at welding line [5] . Contact sensor uses guide bar in welding torch ahead commonly or a sidewall of guide pulley and welding line or workpiece is contacted, pass guide bar or the guide pulley change welding line position becomes aware through photoelectricity, slip rheostat, force wait for means changeover to be telegraphic date, dog in order to supply control system welding line. Its characteristic is disturbed to do not suffer electric arc, the job is reliable, cost is low, ever aborning has gotten applied extensively, but dog precision is not tall, be in at present by other pass feeling method to replace. In addition, some industrial machine philtrum use a contact to pass what feeling means has welding line starting point to search now, for example the robot that Japanese An Chuan company produces has this kind of function a little. Sensor of electric arc type is used solder electrode and can be caused by the distance change between solder workpiece electric arc electric current (to GMAW method) electric arc voltage (to GTAW method) change phenomenon of this one physics will detect the groove center of contact. Electric arc passes feeling means to basically have swing electric arc is passed feeling, rotate electric arc passes feeling and double silk electric arc feeling. Because rotate the whirl of electric arc sensor frequency can amount to above of a few Hz, greatly prep above swings of electric arc sensor swing frequency (10Hz is the following) , rose to detect so sensitivity, improved the precision that welding line dogs, and can rise solder speed, make solder line flowing etc. Rotate the structure that electric arc sensor uses prejudicial gear normally comes true, and the reduces sensor volume with the can effective orgnaization that uses hollow axis electric machinery [6] , if pursue,1 is shown. Graph 1 rotate electric arc sensor [sensor of 6] electric arc has the following advantage: 1) sensor does not occupy extra space basically, the accessibility of welding torch is good 2) do not get electric arc light, magnetic field, splatter, the interference of soot, the work is steady, life is long 3) the distance between nonexistent sensor and electric arc, and signal processing is simpler also, real time sex is good 4) do not need additional device and additional device cost low, the price of electric arc sensor is consequently low so electric arc sensor won wide application, it is the most sensor with robot arc useful solder at present, had called major arc welding machine implement standard configuration of the person. The defect of electric arc sensor is the butt joint of pair of thin panel and lap joint, dog very hard. The blame contact sensor that is used at welding line to dog is very much, basically electromagnetism sensor, ultrasonic sensor, temperature field sensor and visual sensor wait. Among them with visual sensor the most conspicuous, the information content that obtains as a result of visual sensor is big, combine computer vision and the latest technology positive result that image handles, enhanced arc welding machine greatly implement of the person exterior get used to ability. The photoelectricity changeover parts of an apparatus that visual sensor uses is the simplest is unit and sensitive parts of an apparatus, wait like photoelectricity diode; The sensitive and unit line that is one dimension next blast, be like a line blast) of parts of an apparatus of CCD(charge coupling; Application is most is the 2 dimension sensitization with the most complex structure unit face blast, be like a face blast CCD, it is the groovy and sensitive parts of an apparatus of 2 dimension image, it is representing the newest level that at present sensor develops, application is increasingly consequently wide. Soldering robot in all sorts of vision sensor, CCD sensor because its function reliable, bulk small, price clarity of low, image is intuitionistic and got take seriously generally. Especially since 80 time, CCD and the welding line that union of high-powered personal computer photograph produces dog system, the research that makes welding line dogs is crossed went up a new chance to extricateoneself from an awkward position. In arc solder process, because be put in arc, electric arc hot, splatter, and a variety of intense interference such as aerosol. It is the issue that vision of avery kind of sends feeling method to need to solve. According to soldering the working way of system of robot vision solder differs, but will use at soldering robot vision welding line dogs cent is visual sensor of the system: Scanning type mixes structural smooth style, laser to film directly electric arc type. Among them the method that structural smooth style and laser scanning type belong to active vision. Use because be centered at a bit,stimulate beam of light, interference rejection function is betterer. Document [the adoption that mentions in 7] the visual system that diode of CCD camera, laser and scanning lens combine composition suitably, if pursue 2 show, it is pattern of more typical laser scanning application. Similar still have document [the welding line that mentions in 8] dogs method, if pursue 3 show. Graph 3 visions pass feeling system to comprise [7] pursues 4 visions sensor is comprised usually, the visual system of laser scanning type, it is the active vision method that is based on triangulation principle mostly, its job principle is roughly identical. It is the laser point light source that laser canal gives out above all project through optical scanning lens the surface of the workpiece that be measured, the laser after be being reflexed by workpiece surface is photographed to resemble head institute receiving by CCD, scan among them the scanning frequency of lens is in commonly 5-20Hz is adjustable. Through measuring the included angle that reflexes beam of light and axis of CCD key light, the data such as the distance of the included angle that combines foregone transmission beam of light and scanning lens aspect and CCD and scanning lens face, can be in in order to get each bundles of laser the distance of workpiece surface incident point and CCD lens face, can gain the end panel profile of welding line thereby, handle algorithm through proper image, achieve pair of goals that welding line has the vision dogs. The robot that laser and place of CCD photograph union make now solders sensor has had a product to be in in the market sale, but prevailing prices is higher. Passive vision method is to use CCD camera to be mixed through filter decrease mating plate to observe bath directly the area around or welding line. In this kind of method, itself of major electric arc monitors the position namely, detect object (line of welding line center) with object be accusinged (solder fire) in same position, nonexistent detect object and the position of object be accusinged are poor, namely the problem with wrong time, the lead that because heat is out of shape,did not wait for element place to cause so detects error, easier implementation is relatively accurate dog control, and can get a large number of information of contact and bath, this is right solder from adaptive control very advantageous. Because the vision of passive vision and person is more similar, it is the so most hopeful solve welding line of close together butt joint and thin plate to build those who receive welding line to dog problem. And structure of passive vision sensor is simple the price is low, consequently it is a kind of welding line that deserves research very much dogs method. Exist really in this kind of method image is easy get the problem of the serious interference of electric arc, but this is OK through improving filter light method, image handles algorithm and tone conformity to be taken just solve like the method such as hour. The comparison of active vision and passive vision sees next tables. Watch laser welding line dogs the actor defect of sensor and passive vision sensor compares welding line of 4 domestic and international visions to dog when so-called welding line dogs even if soldering, development existing state of affairs detects in real time the error that gives welding line, adjust solder method and solder parameter, assure to solder the dependability of quality. The machining error as a result of workpiece (the preparative circumstance of the size diversity between workpiece, groove) , the precision that hold clip and the heat when soldering are out of shape the existence that waits for an element, teach in order to show - the arc welding machine that emersion means works implement when the person is soldering, often mix because of welding line show teach orbit to have deviation and bring about solder quality drops. So welding line dogs is to assure arc welding machine implement the person solders a of quality important facet. In the sensor that uses in place of robot arc solder, electric arc sensor and visual sensor have prominent place, among them electric arc sensor is used at most, and visual sensor is considered as most the future gets welding line to dog sensor [2] . 4. Welding line of 1 active vision dogs at present active vision welding line dogs the content of research basically has lower part side: 1) the rash club sex that raises laser to dog, if get used to all sorts of soldering contact, wait with contact size variation. 2) the image processing technique of the fast stability in dogging 3) the design problem of sensor, for example the angle of laser and sensor 4) welding line dogs to control a problem mediumly, basically be NN and Fuzzy and both union method. Document [dog to acquire welding line in 8] tall rash club sex and applicability, use two different picture to handle algorithm, before beginning to soldering respectively, detect solder interface model and soldering detect in the process contact feature. Document [all sorts of soldering introduced in detail in 2] the identifying of contact method. And document [9] is used wring receive object model (ArticulateObject Model) will raise the dependability that dog, the feature is searched to nod in using the outline data that this kind of method obtains from sensor (welding line is nodded) , in the feature point point solders. Document [the point of view that 10] treats from image, the picture that studied fast stability handles algorithm. 4.
Welding line of 2 passive visions dogs what passive vision sensor obtains information content big, approach the outstanding good point such as the person's vision, got the wide attention of researcher. Suffer the inspiration of a large number of success application of machine vision technology, people attempt conveys passive visual sense the induction to use a method in, wait like GTAW, GMAW and PAW. Taking the positional side that resemble basically is passivity observes bath reachs his the area around, the feature that uses work additionally observes other area and obtain welding line information. The camera in most research is the position in inclined upper part is taken resemble, and OK when the butt welding of large canal take from the flank of bath picture, can obtain more substantial information so [11] , can realize welding line to dog to be controlled with bath at the same time. When to bath robot the extraction of around area resembles, take choose electric arc brightness commonly like hour small and the hour with stable image. Pulse GTAW solders in, take secure the some hour during every pulse radical is worth normally like hour, through power source synchronism pulse is controlled take like hour. When GMAW solders, take it is short circuit hour normally like hour. In using the research that passive vision sensor has welding line dogs at present, use a camera commonly, the welding line that dogs is planar. Because obtain high information very hard according to a picture,this is. Although there is the method that restores exterior figure according to image of a gray scale in computer vision technology, but because bath image itself is very complex and there is time to ask in controlling a process, dog very hard in welding line so in implementation. Although use two camera to use height of computation of stereo vision technology, the feature nods it is more difficult also to match. Use passive vision to dog so further research still needs on the problem of welding line height. 5 conclusion solder the robot serves as solder a of automation main carrier is sure to receive more wide application in our country, and welding line dogs is arc welding machine implement a of person application important research way. Pass in all sorts of visions in sending feeling means feeling is have an outlook very much send feeling means, among them passive vision is passed because feeling has more advantage, will become heat of a research. CNC Milling
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