1204 KB39 KB199920252015Jeremić, OliveraKapor, Nenad J.Milinović, MomčiloPetrovic, Daliborštevilka:3letnik:61str. 167-175, SI 33ISSN:0039-2480COBISSID:13936155URN:URN:NBN:SI:doc-3WHJ8SDBenZveza strojnih inženirjev in tehnikov Slovenije et al.Strojniški vestnikciklično obratovanjedeterministično modeliranjeoperacijespecialni strojiverjetnostDeterministic mathematical modelling of platform performance degradation in cyclic operation regimes|This paper considers the modelling of extreme-capability working platforms that are operated in periodic cycles, each cycle having a pre- defined number of operations that affect the working surfaces. A novel hypothesis is introduced about the platform-degrading effects that cause an equivalent decrease in the successful operations after repeated cycles. Deterministic modelling, based on the basic equations of Lanchester and Dinner, is generalized here to include coupling between parameters. The newly developed mathematical model of performance degradation is in good agreement with both experimental measurements and numerical simulations. It is assumed that the new variables and their correlations link the Gaussian distribution and the observed performances of the testing platforms. Relative probability dispersions of affected surfaces are derived, as a new indirect referencing figure of merit, to describe simulations and compare them to experimental test data. The model proves a hypothesis that the degrading effects are a function of the platform capacity, frequency of operations and the number of available cycles. Degradation effects are taken into account through an equivalent decrease of effective operation capacities, reflected on the properties of the affected operating surfaces. The obtained estimations of degradation could be used in the planning of platform capacity as well as in the selection of real affected surfaces in various machining systems and for a wide range of different materialsNa področju strojev za obdelavo površin trenutno ne obstaja poenoten teoretični model za povezovanje spremenljive zmogljivosti strojev v cikličnih delovnih procesih, ki se izkazujejo v vplivu na kontinuirno obdelane površine. Modeliranje v operacijskih raziskavah ponuja določene modele medsebojnih odvisnosti med dvema matematično neodvisnima objektoma. V teh modelih pa ni obravnavan samo en objekt oz. stroj za obdelavo površin kot delovna platforma, ki delovne operacije izvaja ciklično in zaradi vpliva ponavljajočih se ciklov samodegradira. V zasnovanem modelu je bilo privzeta hipoteza, da platforma samodegradira, hitrost degradacije pa je spremenljiva in sorazmerna z realno hitrostjo izvajanja operacij, zmanjšana za tekoče število preostalih neizvedenih operacij z razpoložljivo kapaciteto. Ti vplivi se merijo z določanjem statistične variabilnosti parametrov obdelovane površineTEXTznanstveno časopisjejournalsSlovenian National E-content AggregatorNational and University Library of SloveniaUniverza v Ljubljani, Fakulteta za strojništvo