THE MULTI PARAMETRIC STAND FOR MECHANICAL TESTING LINEAR ACTUATOR MECHANISMS

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1 The 3 d Intenatinal Cnfeence n DIAGNOSIS AND PREDICTION IN MECHANICAL ENGINEERING SYSTEMS DIPRE 12 THE MULTI PARAMETRIC STAND FOR MECHANICAL Vasile NASUI, Radu COTETIU, Niclae UNGUREANU Technical Univesity f Cluj Napca, Nth Univesity Cente f Baia Mae, ROMANIA vasile.nasui@ubm. ABSTRACT This pape has a pupse the achievement f a new appach f expeimental eseach using a new expeimental stand f mechanical testing f the linea actuat mechanisms and pducts with linea mtin. In hadwae cnfiguatin, thee ae the fllwing cmpnents whse main chaacteistics ae: linea actuat, taduces, and data acquisitin bad; accunt unit, actuat inteface and bad f cntl lgistics. The stuctue f stand cntains vaius mdules that allw pducts testing with diffeent inputs and utputs gemetical psitins. It is develped a cmplex mniting system that allw mechanical testing and autmate calibatin f linea actuats, acquisitin data and signals and pcessing f these. Senss system can be cnfigued taken in accunt types f actuats and testing pgammes adpting adequate psitin, speeds, and tques, fces and vibatins senss Keywds: paametic stand, mdula stuctues, mechanical testing, linea actuat 1. INTRODUCTION Owing t cntinuus develping equipments based n new slutins, the elect-mechanic acting achieves me and me pecisin. In view f cnstuctive and functinal ptimizatin f the actuats and f the extensin f thei applicatin dmains new methds and techniques ae being tied in pesent eseaches. The applied eseaches in the field f the actuats have aimed at ceating an assembly cnfiguatin called stand in de t study the dynamic behaviu using a numeical data acquiing mdule and a mdule f ptimizatin paametes [3]. The mdula mechanical actuats epesent a new cncept in mechanical tansmissins f vaius types and destinatins that efficiently eplace classical systems mechanically, hydaulically and pneumatically activated [9, 10]. The linea actuat is cmpsed f a mt tuning a scew in which the nut n scew is nt allwed t tate. One type is the electmechanical actuat, which cnvets the tque f an electic tay mt int linea mechanical thust (fig. 1). The actuat has a cmplex stuctue, the mechanical pat being cmpsed f cetain elements which ensue a high kinematic and dynamic pecisin, and the cmmanding pat being epesented by a cmpute-led system, based n apppiate sftwae. These pvide the ptimal slutin f the cnstuctin f quantitative and qualitative mechanical tansmissins due t a wide ange f usage, high efficiency, cinematic, dynamic capacities and high pecisin. The elect mechanic linea actuats, which ae mechatnic pducts and they ae pat f the intelligent flexible systems f manufactue and they have t fulfil special equiements which impse new cncepts f design [3]. The esults btained by detemining these paametes ae t be cmpaed t the indicats nminated by the manufactues and by technical dcumentatin. Taking int accunt that at the pesent stage thee has been an impvement and extensin in the industial bts, it is equied a new efficient system f checking the kinematic and dynamic paametes [1]. 1

2 Fig. 1: The veall scheme f linea actuat system Checking thei pefmances is abslutely equied in view f achieving guaanteed applicatins accding t technical chaacteistics impsed by pecise cnditins f psitining and epeatability. These measuements ae als necessay in the case f sme tanslatin mdule f linea industial which ae fequency applied in diffeent industies instead f classical actuats [3]. Fig. 2. The tial stand f linea actuat maximum speed f sampling, data tansfe); accunt unit (memy, micpcess, and vide sceen), actuat inteface. The system ensues the equied pefmances with the help f eactin cils f speed and f psitin. The eactin cil f speed cmmands the acting sev engines and unde the tuatin aspect cmpises besides the engine and the amplifie, cmpaat and tahgeneat. The psitining cil is made up f cmpaats, the amplifie, and the mving tanslats. In de t cntl the pcess, a specialized mdule with data acquisitin system takes ve fm the pcess f acceleatin paametes and efines it by taking int accunt the shifts fm a basis value and the dynamic f this shift [4]. These efined values ae analyzed in the mdule f fuzzy lgistics when the final decisins f ptimizatin ae taken int accunt. The values stcked in the memy, apppiately efined, cnstitute the inputs f fuzzy analysis system stage that equies the implementatin f intecnnecting pgams, data tansfe and the fuzzy ne. The tial stand f industial linea actuat is pesented in the figue 2 and figue 3. The pape cntinues the auth s peccupatin egading the eseach f the electmechanic actuat mechanisms and efes the esults btained by applying a multiple paametes measuing stand n these types f actuats [10]. The eseach and the data egading this type f mechatnic pducts elatively new, based n analysis and stuctual and kinematic synthesis led t seveal applicatins and diffeent denminatins. We ae ging t fcus n this stating fm the classic al measuing stuctue t the geneal methd f slving the measuing pblem f the kinematic and dynamic paametes in the case f the stuctual cnfiguatin f the type f linea actuat mechanism type [3] THE CONFIGURATION OF THE MEASURING EQUIPMENT In de t impve and t study the pssibilities f egulating and cntl f the actuat mvement a new eseach diectin has been tied using cmplex systems f data acquiing. Thus a cnfiguatin has been used whse patten is pesented in Figue 3. As it esults fm the patten in hadwae cnfiguatin, thee ae the fllwing cmpnents whse main chaacteistics ae: linea actuat, taduce, data acquisitin bad (numbe f channels, Fig. 3. The tial stand f industial linea actuat The ealizatin f a fuzzy cntlle is pusued with the intductin f the systems in the cntl cicuits f the actuats mvement, checking its functining in eal time. This supei level f high cmplexity will ensue the pssibility f the adjustment and the extensin f the esults in many the fields f applicatin in de t slve sme ptimizatin pblems. The tial multi paametic stand f measuing linea elect-mechanic actuat is figue 3 is cmpsed f: 1. hydaulic bake installatin; 2. pessue tansduce; 3. fce tansduce; 4. displacement tansduce; 5. ptical ule; 6. linea actuat; 7. speed tansduce; 8. data acquisitin bad; 9. pwe measuing kit; 10. cmpute; 11. display device. 12. suppt.

3 All these can be best achieved nly by using the methds f mden design by using the technique f numeical cmputatins such as that f the vitual pttype. Setting up the best f slutin by vitual mdelling ffes the idea f the veall technical cnceptin f the actuat pduct, its pssible cmpsitin by the apppiate stuctual slutins, such as the functins f its elements. The technical system f the linea actuat pefected thugh this methd has a few basic chaacteistics expessed by paticula indicats such as: adjustable acting, high pecisin, and efficiency ptent capacity, a ank f high speeds, numeical cntl etc. The mdelling f the cmplex functining is vey difficult eaching system f equatin estictins and bjective functins which tgethe with the lage amunt f infmatin make them difficult t use. 3. THE CONTROL OF THE POSITIONING OF THE TRAINED LOADING AND THE MODELING The cntl f the psitining f the tained lading and the mdelling f these psitining systems equie an equatin systems f nn-linea equatin which imply sme paametes difficult t identify, such as the fequencies f pecisin f the cmpsing equipments, the fictin fces etc. Thee is a vey high numbe f cnstant impvement and new systems mvement evlutins cntinue t appea. The pduced vaiants f fm [6] pvide smth cntlled mvements in the systems with clsed pen lp when the develped fce can be egulated by pwe cntl. The favued mechanism in mst f the cnstuctins is the ne with ball scew because it delives a quick answe and limited acting angles. The actuats ae ideal f limited mvement angles, psitin equipment and autmatic applicatins. Thee ae vaius types f mts that ae used in linea actuats, but DC mts ae mst cmmn. Linea electic actuats als vay in the way hw the mt is integated in t the actuat bdy. We knw that using the mathematic statistics is a key fact in the develpment f the apppiate methd f analysis and decisin upn a situatin given by the expeiment. The necessity f statistic pcedues esults fm the fact that the inductive infeence being nly pbable it is necessay a methd t establish in what way the vaiety bseved can be quantified and masteed. The basic idea f the statistic mdelling is that f plnging the cnclusins dawn fm the investigated mateial upn the geneal cllectively whee it came fm. In the technical field f sme cmplex pducts which imply estictins t sme attempts and samples f paametes f sme technical cmpnents (esistance samples, analysis, destuctive checking etc) thee is a elatively small amunt f data f measuement within the each f the expeimenting eseache. In this case f eseaching the investigated phenmenn in view f the legitimacy f the statistics the pblem is tansfeed fm the theetical plan f the deductin f new lws and cnnectin n the lgical way by cunting that with the help f geneal hypthesis. We apply an infeence f a special type, the chaacteistic f the limited infmatin that they had in ste. In spite f all these, we peate with expeimental date as pecise measues althugh we initially admit that the mdel cntains es by impsed simplificatins, the esult f its applicatin epesents an appximatin f the eal mdel. That s why in mdelling the cmplex systems we admit the pinciple f incmpatibility accding t which the me cmpatible the systems, the smalle the pssibility f desciptin with the help f a stict system; the pssibility deceases t a level whee the pecisin and elevance have n place. The mathematic mdel f statistic wking f the expeimented date cntains sme cnstants a, b, c, is f the fllwing fm, elatin (1): y i f a, b, c,... x i (1) The maximum diving mment necessay t vecme inetia pduced when we have acceleatins is calculated basing n a elatin in mechanics at the mechanical system in figue 1, [5]. F0. l F. l M a J M M K M B i (2) M 2 2 whee: J M is the system inetia mment, [dan mms 2 ]; - the mt angula acceleatin, [ad/s 2 ]; J M. 2 - acceleatin mment necessay t vecme inetia; M M - intenal fictin mment in the mt, [dan m]; F 0 - initial ecmpessins fce, [dan]; F - The final axial fce, [dan]; M B - fictin mment in beaings, [dan m]; i - eductin ati. 3

4 The pefmances ae appeciated thugh the diffeence in time and space between the pgammed psitin and the eal ne. The theetic eseach unde the aspect f the phenmenlgical enegetic aspect eveals the necessity f cnsideing in a system and f infmatics, especting thus an inf mechanic system. It is admitted the pinciple f incmpatibility accding t which the bigge the cmplexity, the smalle the pssibility t the level whee the pecisin and the elevance each the. 4. PROGRAMMABLE MOTION CONTROL SYSTEMS An actuat's functin is t pvide thust and psitining in machines used f pductin testing. The mtin cntl system s pupse is t cntl any ne, cmbinatin, f the fllwing paametes: psitin, velcity, acceleatin, tque. Many mtin cntl systems ae integated int a lage system. Vaius cmpute based devices, such as pgammable cntlles, industial cmputes stand, main fame cmputes seve t link and cdinate the mtin cntl functin with the functins. Thus, a me integated mtin cntl system wuld appea as shwn belw: the assembly f the pcess f develping new pducts, cveing the cnceptin aspects, manufactue and the link between them. The essential cmpnent f many autmatic cntl systems is actuat. The applicatin f a specific cmmand causes a cespnding signal at the input thugh actin input tansduce. The esult is an unbunded incease in cntlled vaiable and lss f cntl by the cmmand suce. The geneal fm f the blck diagam f a feedback cntl system is shwn in the figue 5. In de t develp and ptimizatin patten accding t vey stict engineeing equiement it is necessay the intductin f a numbe f pefmance citein and the fmulatin f sme apppiate bjective functins. The vect t be ptimized, that will satisfy the cnstains: cntact stess; basic static and dynamic axial lad (dan), -static axial igidity dan/ m; - safety fact f ute speed; -the enegetic efficiency (0,80 0,99); -life duatin ( hus); -the psitin pecisin ( p max /l), epetability 0,1/100mm [9]. This esults a chaacteistic f functining specific t each measue f tanslatin unit accding 4 t the dimensin and the step f the mving scew with which it is equipped. These estaints efe the achievement t the pssibility f achieving technical pefmances efeing t the paametes f functinal gemetical pecisin. These ae essential in the case f using psitining systems fm bts, machine-tls cmpute cntlled, specific t tansity cnditins with fequent speeding and baking, stating and stpping at a. fixed pint. They have t be eliable and wk stably in evey situatin. The actuat cntlle shuld be eliable itself and independent fm the equipment failues. The electmechanical unit is cntlled thughut a pwe utput blck. The cntlle nly sets pwe cntl (P C ) and diectin (d) lines t a equied state and the pwe utput P U ealizes pweing f mt. A cntl blck diagam f the system is shwn belw figue 4 The cntlle gets infmatin abut the lad f the unit thughut lad (F) line. The mtin cntl system s pupse is t cntl any ne, cmbinatin, f the fllwing paametes: psitin (p), velcity (v), acceleatin (a), tque (T). C m p u t e Fig. 4: Established actuat blck scheme 5. THE THEORETICAL DYNAMIC MODEL OF THE ACTUATOR This system can be used t advanced mechanisms, elevate and manipulate devices, tatin devices etc. The linea actuat is cmpsed p d v C n t l l e P C d F T P w e b l c k P U Mechanism actuat

5 f a mt tuning a scew in which the nut n scew is nt allwed t tate. This allws linea mtin f the nut f the length f the scew. A psitin at sme pint alng the scew is cmmanded by the use and the mt tuns the scew until the nut eaches that psitin. The mt tates the dive scew by a synchnus timing belt dive, wm gea dive, a cupling diect inline dive, cnnected fm the mt shaft t the scew. Thust is tansmitted fm the dive nut, t the tanslating tube. An actuat's functin is t pvide thust and psitining in machines used f pductin testing. One type is the electmechanical actuat, which cnvets the tque f an electic tay mt int linea mechanical thust. F the mment f taining the scew, we need the aveage fce with we lad the system, the pace f the scew and the efficiency which the scew n lls ffes. The mden actins eplace eve me fequently the egulating mechanic tansmissin because these pefmances dn't fit anyme the demands impsed by the use by inceasing the pwe pe unit f vlume f the active mateials. Tday, the electical egulating actins ae imptant pats f the machine tls with quick evlutin, fm the actins f cntinuus electic pwe t thse with altenative pwe ae eunited as fa as the high speed f egulatin and pecisin f egulating, the cuple ae cncened as well as the gd dynamic the quality facts. We can memize diffeent steps f numbe f tatins in bth ways and als thee can be assued the passing n ve the fequencies f esnance memized by the cnvete. The pesent day develpment in the sftwae field allws the cmmn develpment f sme slutins with multi-functinal univesal machines f the sev-cnveting type f the psitining and mvement actins. The using f the digital technique allws such a bi-diectinal tansfe f data withut supplementay elements (just in time) thugh a paametic seial inteface at a cental leading system, which can integate the eal values f the paametes at any hieachic level. This study makes it pssible t slve sme aspects specific t the dynamic f actuats, useful f the eseach and the geneal design f these tansmissins, as well as f thei explitatin unde vey safe cnditins. The equiements f the mechanic cnstuctin f the actuat ae me ften dynamic, which give bith t the acceleatin f the mvement and f the fce f inetia which can cause vibatins in the end. If the system is put ut f its state f stability due t an impulse and if this impulse is eliminated, then the system executes fee scillatins, duing which, thee is a cntinuus exchange f kinetics and enegy f disttin. In the case f cntinuus actin f the distubing fce, the system executes fced scillatins. Accding t these dynamic lading cefficients we can appeciate petty well the enduance f the actuat and the degee f thei lading. On the basis f the dynamic cefficient we can fllw: the exact limitatin f the wk pupse, accding t the maximum dynamic lading which appeas within the flexible links in the mechanisms, the values f the maximum acceleatins and f the minimum functining time in the peid f the stat-up, f baking and the fequencies f scillatin f the suppts. The scheme f the egulating actin in the altenative electic pwe is pesented in the figue 5 accding t which the system wks. The system f measuing linea elect mechanic actuats is cmpsed f: actuat; cntlle, display and cmpute. The blcks which can be used, ae fund in the libay within the pgammed ae we can define ceate the blcks we can tun t the use f extenal functins used in the Mat Lab pgam. Psitin Cntlle Cmpute PC AC Fig. 5. The scheme f the egulating actin in the electic pwe Afte ceating the mdel, this is ciculated, and the simulatin can be visualized using a display whee we can ead the numeical values f the analyzed signal the signal can be analyzed by using the gaphics with the aid f ne f the blkes f type SCOPE, this making pssible the analysis f the esults. F the mment f taining the scew, we need the aveage fce with we lad the system, the pace f the scew and the efficiency which the scew n lls ffes. F the calculus f the necessay mment 5

6 t vecme the fictin in the lling beaing we take int accunt the aveage fce which is suppted by the system the axial fce which can be vetaken by the lling beaing t its cnstuctin we ecmmend ae lling beaing which vetake the adial and axial fces and the intei diamete f the cap the fictin fce between, the blt nut wile be as cnstants. F the calculus f the acceleatin mment, the algithm f calculus diffe, having me values and at diffeent mments f the cicuit while calculating the angula acceleatin, the educed insetin mment f the engine shaft, the inet in mment f the scew, the angula speed, the linea speed, the pace f the scew, the inet in mment f the engine and the necessay tuatin. The static cnvete f fequency achieves the electic dive engine feeding, f the asynchnus type f geneal use, with a vaiable fequency vltage, maintaining a cetain vltage - fequency chaacteistic. Thus the vaiatin f the engine tatins numbe is achieved and implicitly, that f the utput tatins numbe f the educe, is a vey lage field The ati between the maximum and minimum numbe f tatins, at utput, is the biggest. The vaiatin f the utput numbe f tatins is achieved at a cnstant cuple, up t the nminal numbe f tatins, and the numbe f tatin abve the nminal ne, at cnstant pwe (by cuple decease). It can be utilized at any planetay educe dive whee a cntinuus utput numbe f tatins cntl is cnvete equied. The cect definitin f the ecnmic functining egime f an electmechanical linea actuat must take int accunt, n the nne hand, the clues that chaacteizes the ecnmic egime. Shwn belw thee ae tw diagams depicting the basic elements f the tw mst cmmn electic mtin cntl systems: stepping mt- based and sev mt- based. Each has advantages ve the the, sme f which ae highlighted in the diagam. Thee ae the taining electic pwe and the efficiency f all the stuctual cmpnents. In the tansity dynamic egime, n de t maintain a cnstant f the efficiency at the nminal pwe f the pwe dissipatins suppses the knwledge f a weight gaphic as exact as pssible. The appeciatin f the functining ecnmic egime shuld be dne sepaately f each type f actin engine as well as f evey nminal paamete which changes, that is f each atificial chaacteistic. 6 Saving the electic enegy can be dne by imptant measues in the whle chain f the actuat system stating fm the filling pint, passing t the cntl ne the egulating ne and ging n with the acting engine and the cinematic tansmissin. 6. SUMMARY AND CONCLUSIONS The esult f the eseach we can value immediately any system f linea mvement because it has as a basis the newest techniques f mdelling in the field. These have as an bjective the develping f new system f elect-mechanic linea actuat type as well as pefecting the existent nes in a vey sht time and in highly enegetic and ecnmical cnditins. The applicative and expeimental eseaches viewed the pactical checking and the making up f the theetical pattens used in the utput and als cnvegences t the ways f appaching the pblems t eality. The cnceptin and its manufactue assisted n the cmpute has as applicatin field the assembly f the pcess f develping new pducts, cveing the cnceptin aspects, manufactue and the link between them. The wk integates itself int the pesent day eseaches in the field f the develpment f the mden mechanic tansmissins making cntibutins in thei ptimal design. In the futue the eseaches can cntinue f the develpment f new applicatins n the types f mechanical tansmissin using this methd and diffeent mdula cntl labaty. The develpment pespectives aim ptimum slutins equipped with mechanisms f tansmissin and tansfmatin f the mvement with high efficiency and fiability. Getting t knw the behaviu f the system is achieved as suppsed t knw the eal behaviu f the system which makes the eseach and the mdelling activity t be a cyclical ne. The eseach is f geat imptance as the pesent calculatin algithms egading the main dynamic paametes, pwe and mechanical efficiency. ACKNOWLEDGEMENTS The expeimental eseaches f the linea elect mechanic actuat ae the utcme f the eseaches dne by the Labaty f The Basis f Expeimental

7 Reseach f the Technical Univesity f Cluj Napca, Nth Univesity Cente f Baia Mae. Faculty f Engineeing. The auths make the best f the eseaches dne within the gant egading the develpment f the actuats within the flexible systems f wking. REFERENCES 1. Adian, O. s.a., 1999, Dinamica btil industiali, Editua BREN, Bucuesti, 2. Bangiu, Th., Advanced Rbt Mtin Cntl. Editua AGIR. Editua Academies Rmani, 3. Chiiacescu, S. T. Dinamica masinil-unelte plegnme. Bucuesti: Editua Tehnica Gillinch, G. R., 2003, Dinamica masinil. Mdelaea sistemel tehnice, Editua AGIR,. 5. Maties, V. et al., 2000, Actuati in mecatnica, Editua Mediamia, Cluj- Napca, 6. Mha, C., Ctet, E., Patascu, G., 2001, Simulaea sistemel de pductie. Editua Academiei Rmane, 7. Mntgmey, D.C., 1996, Design f Analysis f Expeiments, 4 th Editin, Jhn Wiley & Sns, New Yk, 8. Ispas, C., Pedencea, N., Ghinea, A., Cnstantin, G. 1998, Machine Tls, Editua Tehnică. Buchaest. 9. Năsui, V., 2006., Actuati liniai electmecanici. Editua RISOPRINT Cluj Napca. 10. Năsui, V. 1996, Optimizaea andamentului mecanic. Editua Univesităţii de Nd din Baia-Mae. 11. Olau, A. Dinamica btil industiali, Bucuesti: Editua BREN, Ppa, A., 2002, Cntlul digital al sistemel mecatnice. Editua Oizntui Univesitae Timisaa,. 13. Patt, J., Tes, A., Dilwth, P., Patt, G., 1996, In: Pceedings f the1996 Intenatinal Cnfeence n Inteligent Rbts and Systems- IROS Usu, I Tecuceanu F., Usu T., Fm bust cntl t antiwindup cmpensatin f electhydaulic sev actuats, Aicaft Engineeing and Ae-space Technlgy, MCB Univesity Pess, 70, n. 4, pp , *** Linact - Use s manual Linea Actuats, Electmechanical Systemes Labaty, The Univesity f Alabama 16. *** Data Acquisitin Devices type ADUC 112, Analg Device. 17.*** Wld Rbtics, Fist Quate 2006 Rbt Sales Impacted by Dwntun in Autmtive Maket, 05/03/ *** THOMSON 2000 Advanced Linea Mtin Systems. Thmsn Industies Inc.Washingtn 7