Be based on sheet piece the research of pilot of fixed position of pneumatic position servo of machine and application

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System of 1 foreword pneumatic has clean, free from contamination, volume enough, weight mixes origin of small, gas gently cost is low advantage, already was applied extensively at industrial automation circumstance. Rise as what produce process automation rate, gain ground in baric drive, development while, baric servo controlled a system to also get developing quickly, apply increasingly at each respects. Develop as project technology, to a process or the control action demand of a monomer is rapid and reliable, answer fast, precision tall, frequency band is broad, these requirements also are the development trend of system of baric servo control. Because pneumatic servo locates the technology appears, be taken seriously by the height of industrial group and academia, move conveyer of robot, pneumatic for gas large-scale enter open up of industrial automation domain very broad perspective. As the development of industrial automation technology, traditional pneumatic system can be in only position of two mechanical set locates reliably, and its move speed can rely on checked throttling valve only single set, condition of this kind of set often cannot satisfy the need of the automata of equipment, consequently report - enrage servo, locate the system receives wider and wider application especially. Because use phone - gas fixed position realizes stepless many a little bit to locate conveniently (have flexible fixed position) with stepless speed regulation. In addition, the athletic rate that uses air cylinder of servo fixed position is successive and adjustable the kind of bumper of end position of crock of throttle air entrainment that the gender replaces a tradition, can achieve result of first-rate speed, amortize, the behavioral time that reduces air cylinder substantially, shorten working procedure metre, improve labor productivity. In pneumatic servo domain, although return,not be very mature at present, but also obtained very good result, but it is to be based on what labour accuses machine, PC and undertake developing study for the most part, the cost that uses in industry so is higher, no-go also, the control system of the article uses sheet piece machine, volume is minor, the spot is debugged convenient, apply in industrial production, be helpful for reducing cost, and more agile. The builds this system control principle of 2 maths model pursues, if the graph is shown 1 times, executive component is the chosen air cylinder that do not have lever, controlling what component chooses is medium shut type the discharge to pneumatic loop and direction have a powerful person of control of 3 5 scale direction control, feedback component chooses magnetism to send telescopic displacement sensor undertakes to the position of lever of air cylinder piston real time detects. This system is to use a powerful person to accuse a crock to control mode, accuse a crock to undertake maths builds a model to a powerful person. A powerful person dominates the working principle picture of the crock, if pursue,2 are shown. A powerful person accuses the input of crock system to be core of a powerful person of electromagnetism a powerful person to cover displacement X at a powerful person relatively, systematic output drives laden displacement Y to do not have lever air cylinder, the total mass of athletic component of the system is M, the agglutinant damp coefficient of air cylinder is B, the coulomb attrition force of the piston is Fc, enrage source pressure Ps. Undertake to air cylinder force is analysed sufferring above all, the differential that lists as follows is equational. Type is shut in controlling a powerful person to be 0 mouth quadrilateral pilot valve, the diameter of core of a powerful person of pilot valve is D. By the piston Ymax of the oldest rate decides the Mmax of the largest mass flow that is in through controlling area of cut of pilot valve passageway. The compression when the piston is Ymax of the oldest rate airy is the biggest Q=Af Ymax of academic cubage discharge. The control that the working gas that enters air cylinder is course control a powerful person is sectional flow into air cylinder. Through a powerful person sectional gas can regard inlet pressure as to be Ps, outlet pressure is P, the linear function that the mouth area of a powerful person can regard as. The course that gas passes mouth of a powerful person is a complex process, calculate to simplify, regard gas as ideal gas, oversight heats up energy loss of exchange to wait, regard aeriform flow as a process that waits for entropy, use Sanville.

F.

Does E discharge formula have: ? ? of  of  of storehouse of honest of  of Yun of  of leech  live abroad criterion the area gradient W= of a powerful person! D, h0 is the gap amount of core of slippery a powerful person and apartment of a powerful person, capacity coefficient Cv. K is compress K=1 of index of airy heat insulation.

4. Consider additionally aerate the process is approximate isotherm namely the oversight temperature influence to aeriform density, the density: of gas of knowable air feed? Ignoranting Piao tastes condyle of exacting of persimmon of Qia of  of shelfing  of U of  of Ju of an old name for Japan to fight  ? to establish above various, undertake Laplace alternates, is the transfer function that gets a powerful person accuses a crock: ? The null coefficient that air cylinder of street? V- includes a powerful person or family of bulk; C3- also calls discharge gain; C4- pressure - capacity coefficient. The designs this system control block diagram of 3 controller, if pursue,3 are shown. To system of a control, the design of controller is crucial, it undertakes judging to all sorts of things with respect to the cerebra that is equivalent to a person, undertake modulatory controlling thereby. It is the controller that according to classical control theory or basis contemporary control designs theoretically no matter, need to undertake building a model accurately to the system, have to pneumatic system strong nonlinear quality, build a model to simplify, constant oversight the influence of the element such as hot exchange, attrition, it is very difficult still to should build a model accurately to its. And beg solve these equation to need to contrast complex algorithm and many operation. Although be worth the development of computation and computer technology as a result of number, algorithmic complexity and operation quantity already too won't big impact controls rate actually. Contain a lot of parameter that cannot decide in these model equation however, need undertakes begging solution and estimation to these parameter, seek solution these parameter often lack enough information content and news feature, what this restricts a model with respect to huge is accurate with practical. Use intelligent PID, it combines artificial intelligence and automata look, always form the expert's experience a certain number of regulation undertakes be controllinged effectively, and the change of strategy of can online correction control and control parameter with getting used to a process. The input that regards controller as positional deviation E(K) is variable, only deviation a quantity is estimated as control is controller of an one dimension only, the dynamic character; that mirrors controlled object very hard in the round regards the input of controller as variable E(K) of E(K) , Δ accordingly, it is controller of a planar, can the more comprehensive and strict trends that reflects process be accusinged is characteristic, many it is good to because this dominates the result,compare one dimension controller. Outputting variable is control PID pilot each coefficient KP, KI, KD. Does PID control algorithm to be: of increment type algorithm? Jun of Cong radon Song, ! KP of E output variable, KI, KD can be divided into different grade according to spot experience, set its corresponding language is variable, write down: ? ={NB of  of noise made in coughing or vomiting of Cong radon Song, NS, z0, PS, is the control regulation that PB} sums up according to the expert's experience as follows: ? Bao (when K) is very big, because error is very big, reason uses Bang- Bang control, control quantity is the biggest eliminate error in order to quicken, achieve stable state to be worth; when E(K) .

Δ when E(K) >0, state output is worth deviate set-point, deviation continues to increase, become when E(K) is bigger, use PI control to eliminate error in order to quicken, when E(K) is lesser, use PID control, eliminate deviation and; of quantity exceeding tone when E(K) .

E(K)<0> becomes Δ E(K) .

Δ when E(K) =0, e(K) =0, express to already achieved set-point, criterion mouth of shut off valve, ≠ of E(K) 0, Δ E(K) =0, control regulation and E(K) .

Δ E(K) >0 is identical. According to expert experience, can get is like expressing 1, watch 2, watch 3, shows control is variable the subject function assignment of KP, KI, KD and E, Δ E is expressed. According to controlling regulation its control a language to be conveyed as follows: IE=NS Then KP=NB And KI=Z0 And KD=Z0 of Δ of E=NB Then KP=NB And KI=Z0 And KD=Z0If E=NB And of Δ of F E=NB And... this control regulation basically is to be based on spot experience of the expert to undertake modulatory, through in the spot debug an experiment, can achieve very good position result. In this experiment, controller is to be based on sheet piece machine and of the design, odd a machine development is simple, cost is lower, the spot is debugged more convenient also. Odd a machine the AT89S52 that chooses ATMEL company, it is a kind of low power comsumption, high-powered and the system contains 8KB but the 8 CMOS microprocessor of memory of process designing Flash, the resolution that supports converter of; A/D of online process designing, D/A all is 12, can satisfy the precision requirement in industrial application. 4 conclusion and application use intelligent PID to control algorithm, solved a tradition to control a method to build accurate maths model hard, appear easily in controlling a process those who exceed tone, lag wait for a phenomenon. Through undertaking the experiment of the spot studies, this pneumatic position servo can achieve very good fixed position precision, and of the system the smallest repeat precision to achieve ± 0.

2mm; control system is used use sheet piece machine, accuse engine control to be compared with labour, cost decreased a lot of, and volume is minor, facilitating application at industrial spot, development is simple, facilitate debug. Pneumatic technology with its clean, environmental protection, energy-saving the applied proportion in waiting for an advantage to be produced in industry now is bigger and bigger. The application of pneumatic position servo is exceedingly wide also. If be on product line of the application of content shedding respect, automation,each are versed in on of component convey accurately to wait with robot of fixed position, pneumatic. CNC Milling CNC Machining