Embedded soft PLC fictitious machine applies in electric test

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When product of part of a few electrons checks, in the past manufacturer of a lot of production uses afterwards report to contact control system. This system is comprised by discrete element, because circuit is simple, component control precision is not tall, sum difference of class of interference rejection ability, run insufficient stability so, misoperation is frequent, make the test of the product and analysis not accurate. As the high accuracy requirement of modern technology, to get used to market demand, use can make up Cheng controller system of electric to former afterwards report control undertakes transforming, but because module of hardware of each PLC manufacturer is mixed,software structure great majority is appropriative, each other is incompatible, the interactive mode between each module, communication equipment makes the system also each are not identical, this makes control system relatively independent, each other close. As technical progress and the aggravate that the market competes, the control system of this kind of special architecture more and more revealed its inherent flaw. Because be based on the software PLC of PC platform need not special process designing implement, can make full use of the soft hardware resource of the PC, use echelon graph or language process designing directly, have the advantage such as good man-machine interface, because this replaced hardware PLC gradually, become the heat of research. 1, the behavioral frequency that principle of electric test system introduces this life to check a system to be able to use timer to control electronic part product, benefit controls behavioral number with clock, fundamental is shown 1 times like the graph. Graph use OMRON CQM1H-CPU11 PLC of PLC of fundamental of 1 electric test adds patulous module, its I/O check the number can amount to 26, can satisfy multichannel test, the undesirable state that the timer time difference that uses the timer that controls behavioral Relay and laden feedback Relay has judging product or load, undertake stopping machine protection to the system, product or load are used to be in after the experiment is finished the character of machinery and electric field undertakes evaluating to its product. Among them, shutting off Relay of protection, movement and laden feedback Relay is with PLC interior high accuracy timer has pilot, its principle is to use low voltage to control tall voltage, realize tall low-pressure depart, protect Yu the security that tests a system, here those who shut off protection to use is Fuji Electric Co.

Ltd. JapanSC-13AA contactor, compression can amount to 600V, only contact is rated electric current is 32A, behavioral Relay and laden feedback Relay (also can use photoelectricity coupling or voltaic transformer) the MY series relay that is used OMRON. Measure discovery actually with DL750 Scoper these two kinds of precision are not very tall, the error often has 8-10ms. Actual in to the product the evaluation needs a lot of data, need tests a lot of products, need much more independent return so, wiring walks along line difficulty, and can produce parasitism circuit, so, from the compatibility of PLC product and test cost consideration, use current and advanced embedded soft PLC technology, can shorten greatly experimental cycle reduces cost. 2, the PLC of tradition of soft PLC technology passes development of ten years, the technology is already special and mature, with high rate, tall stability, high-powered in industry control domain got applied extensively, meanwhile, as the development of contemporary computer technology and electronic technology, show its weakness gradually in engineering field: Traditional PLC manufacturer hold the market, its product door incompatible, lack the standard that agrees clearly, hard compose builds open hardware architecture; The difference of process designing method of each manufacturer product is very big, technology only sexual is stronger, the staff member grooms time is long, the sexual price that causes PLC is very slower than growing. 20 centuries 90 time metaphase, of the international standard IEC61131 of the swift and violent development of the computer and microelectronics technology and PLC make, produced soft PLC technology, " of technology of all " soft PLC, prop up platform as hardware with PC namely, use software to realize the basic function of standard hardware PLC, enclose the control function of PLC inside software namely, move in the environment of PC, it is control system of the foundation with PC, provided the same function of PLC at the same time, had all sorts of advantages of PC however. Soft PLC technology is mixed by development system commonly moving system is comprised twice partly. Development system moves on PC platform, and moving system moves in embedded on hardware platform, generally speaking, embedded some should move to plant on hardware platform embedded operating system, for instance Clinux of μ C/OS-II, μ . The characteristic of modern development system is compositive commonly change development environment, the interface is friendly, use easily. Soft PLC is embedded the system is to be based on IEC61131 international standard, want to support a few kinds of among them languages necessarily so, the system moves in embedded on hardware platform, responsible explanation is carried out by development the system is compiled, the target file of the generation after the link, moving system manages 3 much to comprise by moving kernel, communication interface and system commonly, its design and implementation precision are very tall, its executive efficiency will affect a system to control medium response rate in the spot directly. 3, embedded the structural composition that the fictitious moving system of platform runs a system is shown 2 times like the graph. Systematic government implement main task is to handle different job, harmonious program to carry out reach read from I/O image write variable. I/O interface can correspond with system of this locality I/O and long-range I/O system. Communication interface makes run a system to be able to have communication with development system or other equipment. Kernel interpreter is the core part of moving system, responsible explanation implements the target code that compiles finished PLC application program by development system. Graph the structural composition of 2 moving systems runs a system to be able to be in a variety of support move on platform, it leaves through distinguishing data division and code, the trends that implements a program is updated and of code efficient dynamic download. (1) the directive that in the implementation on μ Clinux platform soft PLC fictitious machine implements measure to pursue echelon translates Cheng Hong collection and build a grand warehouse; The echelon plan program that writes the user compiles the PLM document of intermediate code form; PLM file change is assembler; Become the assembler of result with assembler collection, the explanation executive interior dictates (PLM file) changeover is a program, collection is carried out into machine code, implementation PLC dictates the machine piles up executive plan, rose greatly to implement rate, at the same time big political integrity made an appointment with memory space; the machine of PLC instruction correspondence the code transplants embedded carry out in the operating system. (2) the two big module of moving system run a system to basically comprise by two big module: 1) the changeover that echelon graph piles up a program to the machine; 2) executive machine piles up a file. The function of every module is as follows: 1) the changeover that echelon graph piles up a program to the machine. The echelon plan program that writes the user above all compiles the PLM document of intermediate code form, it is PLM file change assembler next, use the assembler with assembler collection successful transition finally, generation machine code makes executable PLE file thereby. 2) executive machine piles up a file. Embed PLE file in configuring good executive environment, be carried out, accuse the face edition indicator light of machine to monitor the validity of the program through labour. (3) fictitious aircraft is total the design is mixed according to the principle of fictitious machine executive mechanism, to the machine code of fictitious machine executive plan undertook overall design, if pursue,3 are shown. PLC file is echelon plan program save a file, produce PLM document through undertaking to PLC file lexical analyzer, parse and semantic analysis are compiled, call grand collection library next, hand-in-hand travel a series of changeover generates a machine to pile up, produce PLE document; Found a machine to run an environment to implement machine code finally, the grand collection that correspondence of statement of every echelon plan is in grand collection library paragraph. Graph 3 fictitious run overall design block diagram (4) alternate development debugs algorithm to study blame is embedded use this this machine development, machine to debug normally, the development means that this accident goes; And embedded development needs across to develop, great majority uses host machine across is debugged between machine of development, host and target aircraft, the means development that end accident goes. Alternate development debugs algorithm: Program code is written on host machine platform; Solidify monitor comes on target aircraft; Join host machine and target aircraft; Compile link application process, generate executable code; Will executable code downloads target aircraft; Use across is debugged implement undertake debugging; If the program is debugged unusual without discovery, turn to 11) ; The mistake happens when debugging a program, use across to debug implement fixed position mistake; Amend wrong code; Repeat 4) - 10) ; Get on solidify of target engine order in target aircraft. 4, embedded the control system after soft PLC is transformed with checking relay TV5 experiment is exemple. Its ask as follows: Check 5 relay every time, the behavioral frequency of every relay is 5s leaves, 5s closes. According to the requirement, the result with best experiment is every relay uses 6 TV load, namely every TV load is 5s leaves, 55s canal. Input dot has: Switch, check goes out, restoration M, stop time set to measure N second, l of behavioral frequency set, often leave / contact changeover. Among them, m= tests a product several, n, L number is decided by real need. Its algorithm is as follows: Set a total cycle time, make accumulate an error the smallest; Behavioral time and behavioral frequency are designed inside total cycle time, and behavioral frequency; The design is lock of relevant linkage, each other, urgent jockey to wait for a function with restoration; Executive movement and feedback undertake comparative according to product relative standard, decide result and set suspend a program. Use modular programming process designing, each module all is called by the main program, and do not give misoperation for the program, consider voltaic harmonic and the requirement that pound pair of tall power source even. Used algorithm to optimize a design, 5 relay every other 2s a movement, 5 just 10s. Among them program of frequency of a movement is as follows: To it corresponding action is as follows: This program check gives judgement program to be as follows: Electric current of voltage of bear of graph 4 TV is undee by the graph 4 knowable: When starting, maximum of irruptive electric current is 55A about, irruptive time is 54ms about, often be 8A surely. Graph voltage of 5 electric machinery and voltaic weaveform by the graph 5 knowable: Voltaic lag voltage is about 0.

9ms, its power element is 0.

96. Experimental result and test requirement agree basically. If be not used,optimize algorithmic programming, very tall to power source requirement, so this control system can apply implementation, virtually reduced cost. 5, the advantage after improving and safeguard apparently, through there is the following advantage after above improves: The versatility after use PLC rises greatly, improved onefold before PLC, shortened of the staff member groom periodic; With embedded soft PLC replaces traditional hard PLC, peripheral line simplifies; Modular can implement all sorts of complex control systems, increase conveniently and change control function; PLC can undertake breakdown detects automatically and call the police show, enhance moving security, and facilitating overhaul; Facilitating group control, improve moving efficiency; Need not alter when modification control plan peripheral line. Test and safeguard the item that requires an attention: Reduce expense to improve systematic efficiency, use I/O less as far as possible; Should have urgent jockey and link of proper and interlocking pushbutton; Input and output cannot use same cable; Diode of surge of paralell connection of load of dc inductance sex, in order to prolong the service life of contact; Laden and shunt-wound capacitance absorbs communication sensibility implement in order to reduce noise. To assure to control the dependability that the system works, do good ground connection, dustproof, seek oily, radiation-proof job. This system can use epilogue at the test of the product such as relay, motor, inductance, charger. The following blemish still exists after improving: One of, if load opens circuit, its itself can not detect and protect; If laden short circuit, the product has produced electricity inside short time, can cause a product to destroy safety of minatory even person. Secondly, data is collected not complete, cannot real time monitoring. Use galvanometer to be able to make up for the inadequacy of the a bitth; Use data to collect card to be able to realize real time data to collect. CNC Milling CNC Machining