UDC 621 CODEN: MINSC5 ISSN 1857 5293 MECHANICAL ENGINEERING SCIENTIFIC JOURNAL MA[INSKO IN@ENERSTVO NAU^NO SPISANIE Volume 25 Number 2 Skopje, 2006
Mech. Eng. Sci. J. Vol. No. pp. Skopje 25 2 43 86 2006 Ma{. in`. nau~. spis. God. Broj str. Skopje MA[INSKO IN@ENERSTVO NAU^NO SPISANIE MECHANICAL ENGINEERING SCIENTIFIC JOURNAL Izdava Ma{inski fakultet, Univerzitet Sv. Kiril i Metodij, Skopje, R. Makedonija Published by Faculty of Mechanical Engineering, "SS. Cyril and Methodius" University, Skopje, R. Macedonia Izleguva dva pati godi{no Published twice yearly UREDUVA^KI ODBOR EDITORIAL BOARD Odgovoren urednik Editor in Chief Prof. d-r. Ivan Mickovski Prof. Ivan Mickovski, Ph.D. Zamenik odgovoren urednik Co-editor in Chief Von. prof. d-r Valentina Ge~evska Asoc. Prof. Valentina Gečevska, Ph.D. Urednici Editors Doc. d-r Nikola Tuneski, sekretar Ass. Prof. Nikola Tuneski, Ph.D., secretary Prof. d-r Dobre Run~ev Prof. Dobre Runčev, Ph.D. Prof. D-r Slave Armenski Prof. Slave Armenski, Ph.D. Prof. d-r Janko Jan~evski Prof. Janko Jančevski, Ph.D. Von. prof. d-r Jasmina ^alovska Asoc. Prof. Jasmina Čalovska, Ph.D. Asis. d-r Zoran Markov Ass. Zoran Markov, Ph.D. Tehni~ki urednik Blagoja Bogatinoski Lektura Rozita Petrinska (angliski) Georgi Georgievski (makedonski) Korektor Alena Georgievska Technical editor managing Blagoja Bogatinoski Lectors Rozita Petrinska (English) Georgi Georgievski (Macedonian) Proof-reader Alena Georgievska UDK: NUB Kliment Ohridski Skopje (Oqa Stojanova) Tira`: 300 Copies: 300 Cena: 520 denari Price: 520 denars UDC: "Sv. Kliment Ohridski" Library Skopje (Olja Stojanova) Adresa Address Ma{inski fakultet Faculty of Mechanical Engineering (Ma{insko in`enerstvo nau~no spisanie) (Mechanical Engineering Scientific Journal) Odgovoren urednik Editor in Chief po{t. fah 464 P.O.Box 464 MK-1001 Skopje, Republika Makedonija MK-1001 Skopje, Republic of Macedonia Mech. Eng. Sci. J. is indexed/abstracted in INIS (International Nuclear Information System) www.mf.ukim.edu.mk
MA[INSKO IN@ENERSTVO NAU^NO SPISANIE MA[INSKI FAKULTET, SKOPJE, REPUBLIKA MAKEDONIJA MECHANICAL ENGINEERING SCIENTIFIC JOURNAL FACULTY OF MECHANICAL ENGINEERING, SKOPJE, REPUBLIC OF MACEDONIA Mech. Eng. Sci. J. Vol. No. pp. Skopje 25 2 43 86 2006 Ma{. in`. nau~. spis. God. Broj str. Skopje S O D R @ I N A 372 Vladimir Andonovi}, Aleksandar Andonovi} Analiza na funkcionalnata struktura na branici na sovremeni patni~ki avtomobili... 43 49 373 Janko Jan~evski Presmetki na slo`eni profili vo tehni~kata mehanika so koristewe na programata "TMI"... 51 57 374 Dragan [utevski, Radmil Polenakovi} Otpornosta sprema organizaciskite promeni vo odnos na stilot na menaxmentot spored Adi`es... 59 63 375 \or i Axiev, Aleksandar Sedmak Vlijanie na heterogenosta na zavarena vrska so zgolemeni mehani~ki osobini na odnesuvaweto pri zategnuvawe na epruveti so puknatina vo ZVT. 65 78 376 Hristijan Mickoski, Dame Korunoski, Marjan Gavriloski Optimalna podvi`nost na manipulator, simulirana so MATLAB/Simulink i Virtual Reality toolbox... 79 83 Upatstvo za avtorite... 85 86
MECHANICAL ENGINEERING SCIENTIFIC JOURNAL FACULTY OF MECHANICAL EGINEERING, SKOPJE, REPUBLIC OF MACEDONIA MA[INSKO IN@ENERSTVO NAU^NO SPISANIE MA[INSKI FAKULTET, SKOPJE, REPUBLIKA MAKEDONIJA Mech. Eng. Sci. J. Vol. No. pp. Skopje 25 2 43 86 2006 Ma{. in`. nau~. spis. God. Broj str. Skopje C O N T E N T S 372 Vladimir Andonović, Aleksandar Andonović Function structure analysis of the current passanger vehicle bumpers... 43 49 373 Janko Jančevski Calculation of complex profiles in technical mechanics using "TMI" program... 51 57 374 Dragan Šutevski, Radmil Polenaković Resistance to organizational change versus management styles according to Adizes... 59 63 375 Gjorgji Adžiev, Aleksandar Sedmak The effect of overmatching on a behavior of tensile specimens with a crack in heat-affected-zone... 65 78 376 Hristijan Mickoski, Dame Korunoski, Marjan Gavriloski Optimum manipulator mobility, simulated by using MATLAB/Simulink and Virtual Reality toolbox... 79 83 Instructions for authors... 85 86 Mech. Eng. Sci. J. 25 (2), 43 86 (2006)
Mechanical Engineering Scientific Journal, Vol. 25, No. 2, pp. 43 49 (2006) CODEN: MINSC5 372 ISSN 1857 5293 Received: December 11, 2006 UDK:629.3.067.2 Accepted: January 20, 2007 Original scientific paper FUNCTION STRUCTURE ANALYSIS OF THE CURRENT PASSANGER VEHICLE BUMPERS Vladimir Andonović 1, Aleksandar Andonović 2 1 Faculty of Mechanical Engineering, "SS. Cyril and Methodius" University, 2 District Heating, Londonska St., MK-1001 Skopje, Republic of Macedonia andon@mf.ukim.edu.mk A b s t r a c t: The basic purpose of the vehicle bumper is absorption of impact energy in the collision with another vehicle at smaller velocities. On the other side, numerous statistical data show that over 80% head-on collisions with serious or fatal injuries occur with impact speed range 40 60 km/h, which is considerably more than velocities issued by existing standards [3]. There is no doubt, that just now, the conditions for further high-quality development and improvement of the current and future passenger vehicle bumpers are ripened (independently of the drive system). In the paper a modern designing approach for creating technical product with top performances is presented, by which the current passenger vehicle bumper is analyzed as a system. The existence of the problem is noticed, and on the basis of those data the new task of the bumper is defined. The requirements list is assembled, with the help of abstraction the General Technical Function (GTF) of the new bumper is defined and finally (by division of GTF to partial and elementary functions) the functional structure of the bumper is elaborated. Key words: requirements list (RL); abstraction; General Technical Function (GTF); functional structure ANALIZA NA FUNKCIONALNATA STRUKTURA NA BRANICI NA SOVREMENI PATNI^KI AVTOMOBILI Vladimir Andonovi}, Aleksandar Andonovi} Ma{inski fakultet, Univerzitet Sv. Kiril i Metodij, p. fah 464, MK-1001 Skopje, Republika Makedonija Toplifikacija, ul. Londonska, MK-1001 Skopje, Republika Makedonija andon@mf.ukim.edu.mk Klu~ni zborovi: branik; apstrahirawe; tehni~ka funkcija; funkcionalna struktura Osnovnata namena na branikot e apsorpcija na udarnata energija pri sudir so drugo vozilo pri pomali brzini. Od druga strana, statisti~kite podatoci poka`uvaat deka pove}e od 80% ~elni sudiri so seriozni ili fatalni posledici se slu~uvaat pri brzini od 40 do 60 km/h, {to e zna~itelno pove}e od brzinite na koi postojnite standardi se povikuvaat. Nema somnevawe deka sozreale uslovi za ponatamo{- no kvalitetno usovr{uvawe i podobruvawe na branicite na sovremenite i idnite patni~ki avtomobili (nezavisno od vidot na pogonot). Vo trudot e prika- `an moderen konstruktiven priod kon sozdavawe tehni~ki proizvod so vrvni performansi, pri {to branikot na patni~ko motorno vozilo se analizira kako sistem. Uo~eno e postoewe na problemot i vrz osnova na toa e definirana nova zada~a za branikot. Sostavena e lista na pobaruvawa, so apstrahirawe e definirana op{ta tehni~ka funkcija na noviot branik (OTF), a so nejzinoto razlo`uvawe na parcijalni i elementarni funkcii e razrabotena funkcionalna struktura na branikot.
Mechanical Engineering Scientific Journal, Vol. 25, No. 2, pp. 51 57 (2006) CODEN: MINSC5 373 ISSN 1857 5293 Received: December 25, 2006 UDK: 539.4 : 004.42 Accepted: January 5, 2006 Original scientific paper CALCULATION OF COMPLEX PROFILES IN TECHNICAL MECHANICS USING "TMI" PROGRAM Janko Jančevski Faculty of Mechanical Engineering, "SS. Cyril and Methodius" University, jankojan@mf.ukim.edu.mk A b s t r a c t: This article presents specific method of calculations in technical mechanics, especially in mechanical engineering. Worldwide in technical faculties and schools curriculum of technical mechanics exist. This is the basis for other further disciplines in the knowledge of any mechanical engineer. The statics, kinematics, dynamics and the strength theory, vibrations are parts of the technical mechanics. Some parameters like a position of center of gravity, areas, axial and polar moments of inertia, resistance moments of inertia are the most frequently used parameters in mechanics. There are many exact equations for their calculations. Sometimes, for complex profiles special methods of calculation and determination exist. This paper shows the abilities of computer program "TMI.EXE" based on the "SCREEN CONTACT" methodology [1], for parameter calculation of complex profiles in the machines. Key words: center of gravity; moment of inertia; profile; mechanics; machines PRESMETKI NA SLO@ENI PROFILI VO TEHNI^KATA MEHANIKA SO KORISTEWE NA PROGRAMATA "TMI" Janko Jan~evski Ma{inski fakultet, Univerzitet Sv. Kiril i Metodij, p. fah. 464, MK-1001 Skopje, Republika Makedonija jankojan@mf.ukim.edu.mk Klu~ni zborovi: te`i{te; moment na inercija; presek; mehanika; ma{ina Ovoj trud prezentira eden specifi~en metod za presmetki vo tehni~kata mehanika, osobeno vo oblasta na ma{instvoto. Na site tehni~ki fakulteti i u~ili{ta vo svetot postoi disciplina tehni~ka mehanika. Taa e osnova za site drugi naredni predmeti potrebni na eden ma{inski in`ener. Statikata, kinematikata, dinamikata, jakosta na materijalite, kako i teorijata na oscilaciite, vsu{nost se delovi na tehni~kata mehanika. Nekoi parametri i veli~ini kako {to se te- `i{tata, povr{inite na napre~nite preseci, aksijalnite i polarnite momenti na inercija, otpornite momenti, se mnogu ~esto koristeni vo mehanikata. Postojat to~ni ravenki za nivno presmetuvawe. Sepak, ponekoga{ za slo`eni profili (preseci) postojat specijalni metodi za nivno utvrduvawe i presmetka. Ovoj trud gi prika`uva mo`nostite na kompjuterskata programa TMI.exe koja e zasnovana na metodot ekranski kontakti [1], spored koj se presmetuvaat veli~ini na slo`eni profili kaj ma{inite. Ma{. in`. nau~. spis., 25 (2), 51 57 (2006)
Mechanical Engineering Scientific Journal, Vol. 25, No. 2, pp. 59 63 (2006) CODEN: MINSC5 374 ISSN 1857 5293 Received: February 5, 2006 UDK: 65.011.8 Accepted: March 19, 2006 Original scientific paper RESISTANCE TO ORGANIZATIONAL CHANGE VERSUS MANAGEMENT STYLES ACCORDING TO ADIZES Dragan Šutevski 1, Radmil Polenakovik 2 1 Macedonian Custom, Ilindenska 19, Kumanovo, Republic of Macedonia 2 Faculty of Mechanical Engineering, "SS. Cyril and Methodius" University, dragan.sutevski1@mt.net.mk / radepole@mf.ukim.edu.mk A b s t r a c t: Success of organizational change process is in direct connection with the resistance that appears to that process and the issues related to successfully overcoming that resistance. For successfully overcoming resistance to organizational change the managers or the initiators of those changes must predict the reaction of the people in the organizational system to the proposed changes. Therefore, in this paper the authors represent the results of analysis of the reaction of managers to the organizational change against management styles according to Adizes. The research is obtained with a questionnaire in 50 enterprises in the Republic of Macedonia. Key words: organizational change; resistance to change; reaction to change; management styles OTPORNOSTA SPREMA ORGANIZACISKITE PROMENI VO ODNOS NA STILOT NA MENAXMENTOT SPORED ADI@ES Dragan [utevski 1, Radmil Polenakovi} 2 1 Carina na Republika Makedonija, Ilindenska 19, Kumanovo, Republika Makedonija 2 Ma{inski fakultet, Univerzitet Sv. Kiril i Metodij, p. fah. 464, MK-1001 Skopje, Republika Makedonija dragan.sutevski@mt.net.mk / radepole@mf.ukim.edu.mk Klu~ni zborovi: organizaciski promeni; otpornost sprema promeni; reakcija na promeni; stilovi na menaxmentot Uspe{nosta na procesot na organizaciskite promeni e vo direktna vrska so otpornosta sprema promenite i e povrzana so uspe{no spravuvawe so taa otpornost. Za uspe{no spravuvawe so otpornosta sprema organizaciskite promeni menaxerite ili inicijatorite na tie promeni moraat da ja predvidat reakcijata na lu eto vo organizaciskiot sistem. Zatoa vo ovoj trud avtorite gi pretstavuvaat rezultatite od analiza na reakciite na menaxerite na organizaciskite promeni vo odnos na stilot na menaxmentot spored Adi`es. Istra`uvaweto e sprovedeno so pra{alnik vo 50 pretprijatija vo Republika Makedonija.
The effect of overmatching on a behavior of tensile specimens with a crack in heat-affected-zone 1 Mechanical Engineering Scientific Journal, Vol. 25, No. 2, pp. 65 78 (2006) CODEN: MINSC5 375 ISSN 1857 5293 Received: February 7, 2006 UDK:621.791.05 : 539.219.2] : 519.6 Accepted: March 13, 2006 Original scientific paper THE EFFECT OF OVERMATCHING ON A BEHAVIOR OF TENSILE SPECIMENS WITH A CRACK IN HEAT-AFFECTED-ZONE Gjorgji Adžiev 1, Aleksandar Sedmak 2 1 Faculty of Mechanical Engineering, "SS. Cyril and Methodius" University, 2 Faculty of Mechanical Engineering, Kraljice Marije 16, 11000 Belgrade, Serbia asedmak@mas.bg.ac.yu / gadziev@mf.ukim.edu.mk A b s t r a c t: An experimental and numerical investigation of the behavior of the overmatched welded joint with a crack in the heat-affected-zone (HAZ) is performed. Two cases are considered: crack tip located into the fine-grain HAZ (FG HAZ) and into the coarse-grain HAZ (CG HAZ). In both cases, after the initial growth phase of the crack in FG HAZ or CG HAZ, the overmatching acted as a barrier to further propagation of a crack, directed its propagation towardsweaker and more ductile base metal instead of structures with lower toughness. A detailed three-dimensional finite element analysis was performed in order to explain such a behavior. Key words: overmatched welded joint; fine-grain heataffected-zone; coarse-grain heat-affected-zone; crack propagation; finite element method VLIJANIE NA HETEROGENOSTA NA ZAVARENA VRSKA SO ZGOLEMENI MEHANI^KI OSOBINI NA ODNESUVAWETO PRI ZATEGNUVAWE NA EPRUVETI SO PUKNATINA VO ZVT \or i Axiev 1, Aleksandar Sedmak 2 1 Ma{inski fakultet, Univerzitet Sv. Kiril i Metodij, p. fah 464, MK-1001 Skopje, Republika Makedonija 2 Ma{inski fakultet, Kraqice Marije 16, 11000 Beograd, Srbija asedmak@mas.bg.ac.yu / gadziev@mf.ukim.edu.mk Klu~ni zborovi: zavarena vrska so zgolemeni mehani~ki osobini; finozrnesta ZVT; grubozrnesta ZVT; propagacija na puknatina; metod na kone~ni elementi Sprovedeno e eksperimentalno i numeri~ko istra`uvawe na zavarena vrska so zgolemeni mehani~ki osobini (overmatching) so puknatina vo ZVT. Razgledani se dva slu~aja: puknatina locirana vo finozrnesta ZVT i vo grubozrnesta ZVT. I vo dvata slu~aja na zgolemeni mehani~ki osobini na metalot, zavarot vo odnos na osnovniot metal se odnesuval kako bariera za ponatamo{na propagacija na puknatinata vo strukturi so namalena `ilavost, a naso~uvaj}i ja kon poslabiot i poduktilen osnoven metal. Detalnata numeri~ka 3-D analiza so kone~ni elementi be{e sprovedena zaradi objasnuvawe na vakvoto odnesuvawe. Ma{. in`. nau~. spis., 25 (2), 65 78 (2006)
Mechanical Engineering Scientfic Journal, Vol. 25, No. 2, pp. 79 83 (2006) CODEN: MINSC5 376 ISSN 1857 5293 Received: November 1, 2006 UDK: 007.52 : 004.94 Accepted: January 11, 2007 Professional paper OPTIMUM MANIPULATOR MOBILITY, SIMULATED BY USING MATLAB/SIMULINK AND VIRTUAL REALITY TOOLBOX Hristijan Mickoski, Dame Korunoski, Marjan Gavriloski Faculty of Mechanical Engineering, "SS. Cyril and Methodius" University, hristijanm@mf.edu.mk / dame@mf. edu.mk / marjan@mf.edu.mk A b s t r a c t: In this paper the original developed method for measurement of needed precision regarding realization of assembly between cylindrical elements using of industrial robot with help of MATLAB/Simulink program language is presented. Original MATLAB/Simulink schemes for measurement of kinematics and dynamic parameters of modular pneumatic robot is presented. Algorithm for optimization of specified link movement is developed. Increasing of air pressure in pneumatic cylinders (in our experiment we do such a phase by increasing of force into kinematical pairs), which means increasing of acceleration. Kinematical schemes of PMIR by using MATLAB module Virtual Reality toolbox with a simulation possibility of robot movement, and also changing kinematical and dynamical parameters are developed. Key words: manipulator; optimization; error; simulation OPTIMALNA PODVI@NOST NA MANIPULATOR, SIMULIRANA SO MATLAB/SIMULINK I VIRTUAL REALITY TOOLBOX Hristijan Mickoski, Dame Korunoski, Marjan Gavriloski Ma{inski fakultet, Univerzitet Sv. Kiril i Metodij, p. fah 464, 1000 Skopje, Republika Makedonija hristijanm@mf.edu.mk / dame@mf. edu.mk / marjan@mf.edu.mk Klu~ni zborovi: manipulator; optimizacija; gre{ka; simulacija Glavna cel na ovoj trud e definirawe na sugestii za modernizacija na modularni manipulatori. Za teoretskite istra`uvawa i presmetki e koristen inverzniot kinemati~ki algoritam, implementiran vo programskiot paket MATLAB/Simulink. Poseben akcent e daden na optimizacionata procedura kako matemati~ka interpretacija na produktivnosta. Optimirana e traektorijata koja ja realizira fa}a~ot. Vrz baza na teoretskite i prakti~nite rezultati e doka`ano zgolemuvawe na produktivnosta nad 20 pati.