Obradović, Ratko

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orcid::0000-0002-7167-7938
  • Obradović, Ratko (2)
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Author's Bibliography

Geometrical and mechanical characteristics of deformed balance spring obtained by simulation study

Popkonstantinović, Branislav; Obradović, Ratko; Obradović, Marija; Jeli, Zorana; Stojicević, Miša

(SAGE Publications Ltd, 2016)

TY  - JOUR
AU  - Popkonstantinović, Branislav
AU  - Obradović, Ratko
AU  - Obradović, Marija
AU  - Jeli, Zorana
AU  - Stojicević, Miša
PY  - 2016
UR  - https://grafar.grf.bg.ac.rs/handle/123456789/801
AB  - This paper analyzes the geometrical and mechanical characteristics of balance springs, which have the most important influence on the oscillation rate of the balance wheel and, consequently, the most decisive effects on the timekeeper's accuracy. These characteristics are obtained by a set of SolidWorks simulations of static structural studies based on the finite element model, which are performed and accomplished in a specific and original way. Our study demonstrates that the position of the balance spring center of mass and its momentum of inertia are not constant but depend on the angular displacement of the spring collet end. It also shows that the torque spring rate (the spring stiffness) varies as a function of angular displacement during the balanced spring twist. All results are presented numerically and graphically by a set of diagrams and can contribute to the better understanding of the balance spring geometrical and mechanical features and, therefore, be applied for improving a timepiece's accuracy. Moreover, the method of simulation study disclosed and explained in this paper provides general suggestions and guidance for similar studies. The accuracy of the presented results, as well as the validity of the complete simulation-based method, is proven by the experimentally determined relationship between balance spring restoring torque, stiffness, and spring angular displacement.
PB  - SAGE Publications Ltd
T2  - Simulation-Transactions of the Society for Modeling and Simulation International
T1  - Geometrical and mechanical characteristics of deformed balance spring obtained by simulation study
EP  - 997
IS  - 11
SP  - 981
VL  - 92
DO  - 10.1177/0037549716673453
ER  - 
@article{
author = "Popkonstantinović, Branislav and Obradović, Ratko and Obradović, Marija and Jeli, Zorana and Stojicević, Miša",
year = "2016",
abstract = "This paper analyzes the geometrical and mechanical characteristics of balance springs, which have the most important influence on the oscillation rate of the balance wheel and, consequently, the most decisive effects on the timekeeper's accuracy. These characteristics are obtained by a set of SolidWorks simulations of static structural studies based on the finite element model, which are performed and accomplished in a specific and original way. Our study demonstrates that the position of the balance spring center of mass and its momentum of inertia are not constant but depend on the angular displacement of the spring collet end. It also shows that the torque spring rate (the spring stiffness) varies as a function of angular displacement during the balanced spring twist. All results are presented numerically and graphically by a set of diagrams and can contribute to the better understanding of the balance spring geometrical and mechanical features and, therefore, be applied for improving a timepiece's accuracy. Moreover, the method of simulation study disclosed and explained in this paper provides general suggestions and guidance for similar studies. The accuracy of the presented results, as well as the validity of the complete simulation-based method, is proven by the experimentally determined relationship between balance spring restoring torque, stiffness, and spring angular displacement.",
publisher = "SAGE Publications Ltd",
journal = "Simulation-Transactions of the Society for Modeling and Simulation International",
title = "Geometrical and mechanical characteristics of deformed balance spring obtained by simulation study",
pages = "997-981",
number = "11",
volume = "92",
doi = "10.1177/0037549716673453"
}
Popkonstantinović, B., Obradović, R., Obradović, M., Jeli, Z.,& Stojicević, M.. (2016). Geometrical and mechanical characteristics of deformed balance spring obtained by simulation study. in Simulation-Transactions of the Society for Modeling and Simulation International
SAGE Publications Ltd., 92(11), 981-997.
https://doi.org/10.1177/0037549716673453
Popkonstantinović B, Obradović R, Obradović M, Jeli Z, Stojicević M. Geometrical and mechanical characteristics of deformed balance spring obtained by simulation study. in Simulation-Transactions of the Society for Modeling and Simulation International. 2016;92(11):981-997.
doi:10.1177/0037549716673453 .
Popkonstantinović, Branislav, Obradović, Ratko, Obradović, Marija, Jeli, Zorana, Stojicević, Miša, "Geometrical and mechanical characteristics of deformed balance spring obtained by simulation study" in Simulation-Transactions of the Society for Modeling and Simulation International, 92, no. 11 (2016):981-997,
https://doi.org/10.1177/0037549716673453 . .
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Investigation of Concave Cupolae Based Polyhedral Structures and Their Potential Application in Architecture

Obradović, Marija; Mišić, Slobodan; Popkonstantinović, Branislav; Petrović, Maja; Malešević, Branko; Obradović, Ratko

(Sarajevo: Society for development of teaching and business processes in New net environment in B&H (DRUNPP), 2013)

TY  - JOUR
AU  - Obradović, Marija
AU  - Mišić, Slobodan
AU  - Popkonstantinović, Branislav
AU  - Petrović, Maja
AU  - Malešević, Branko
AU  - Obradović, Ratko
PY  - 2013
UR  - https://grafar.grf.bg.ac.rs/handle/123456789/1928
AB  - Concave cupolae of second sort, combined with the other regular faced polyhedra with at least one matching side, provide many possibilities for the formation of various composite polyhedra. The
paper presents research on regular-faced polyhedral structures obtained by joining the bases of square concave cupolae of second sort, with the appropriate sides of Archimedean solid - truncated 
cube, and its application in architecture, based on geometric, structural, and functional analysis.
PB  - Sarajevo: Society for development of teaching and business processes in New net environment in B&H (DRUNPP)
T2  - Technics Technologies Education Management
T1  - Investigation of Concave Cupolae Based Polyhedral Structures and Their Potential Application in Architecture
EP  - 1214
IS  - 3
SP  - 1198
VL  - 8
UR  - https://hdl.handle.net/21.15107/rcub_grafar_1928
ER  - 
@article{
author = "Obradović, Marija and Mišić, Slobodan and Popkonstantinović, Branislav and Petrović, Maja and Malešević, Branko and Obradović, Ratko",
year = "2013",
abstract = "Concave cupolae of second sort, combined with the other regular faced polyhedra with at least one matching side, provide many possibilities for the formation of various composite polyhedra. The
paper presents research on regular-faced polyhedral structures obtained by joining the bases of square concave cupolae of second sort, with the appropriate sides of Archimedean solid - truncated 
cube, and its application in architecture, based on geometric, structural, and functional analysis.",
publisher = "Sarajevo: Society for development of teaching and business processes in New net environment in B&H (DRUNPP)",
journal = "Technics Technologies Education Management",
title = "Investigation of Concave Cupolae Based Polyhedral Structures and Their Potential Application in Architecture",
pages = "1214-1198",
number = "3",
volume = "8",
url = "https://hdl.handle.net/21.15107/rcub_grafar_1928"
}
Obradović, M., Mišić, S., Popkonstantinović, B., Petrović, M., Malešević, B.,& Obradović, R.. (2013). Investigation of Concave Cupolae Based Polyhedral Structures and Their Potential Application in Architecture. in Technics Technologies Education Management
Sarajevo: Society for development of teaching and business processes in New net environment in B&H (DRUNPP)., 8(3), 1198-1214.
https://hdl.handle.net/21.15107/rcub_grafar_1928
Obradović M, Mišić S, Popkonstantinović B, Petrović M, Malešević B, Obradović R. Investigation of Concave Cupolae Based Polyhedral Structures and Their Potential Application in Architecture. in Technics Technologies Education Management. 2013;8(3):1198-1214.
https://hdl.handle.net/21.15107/rcub_grafar_1928 .
Obradović, Marija, Mišić, Slobodan, Popkonstantinović, Branislav, Petrović, Maja, Malešević, Branko, Obradović, Ratko, "Investigation of Concave Cupolae Based Polyhedral Structures and Their Potential Application in Architecture" in Technics Technologies Education Management, 8, no. 3 (2013):1198-1214,
https://hdl.handle.net/21.15107/rcub_grafar_1928 .