TY - JOUR AU - Stépán, Gábor AU - Hajdu, Dávid AU - Alex, Iglesias AU - Takács, Dénes AU - Dombóvári, Zoltán TI - Ultimate capability of variable pitch milling cutters JF - CIRP ANNALS-MANUFACTURING TECHNOLOGY J2 - CIRP ANN-MANUF TECHN VL - 67 PY - 2018 IS - 1 SP - 373 EP - 376 PG - 4 SN - 0007-8506 DO - 10.1016/j.cirp.2018.03.005 UR - https://m2.mtmt.hu/api/publication/3393017 ID - 3393017 N1 - Funding Agency and Grant Number: European Research Council (FP/ERC Advanced Grant) [340889]; EU H2020 MMTech (H2020-MG/MMTech Grant) [633776]; Hungarian EMMI [UNKP-17-4-III] Funding text: European Research Council (FP/2007-2013/ERC Advanced Grant Agreement n. 340889), EU H2020 MMTech (H2020-MG-2014/MMTech Grant Agreement n. 633776) and Hungarian EMMI UNKP-17-4-III. Department of Applied Mechanics, Budapest University of Technology and Economics, Budapest, Hungary IK4-Ideko, Dynamics & Control, Basque Country, Elgoibar, Spain MTA-BME Research Group on Dynamics of Machines and Vehicles, Budapest, Hungary Cited By :6 Export Date: 26 November 2019 CODEN: CIRAA Correspondence Address: Dombovari, Z.; Department of Applied Mechanics, Budapest University of Technology and EconomicsHungary; email: dombovari@mm.bme.hu Export Date: 28 November 2019 CODEN: CIRAA AB - Variable pitch milling cutters intend to increase performance, but off-the-shelf cutters do not ensure this generally. Depending on the milling process they are selected for, they can perform better or even worse than uniform pitch cutters do. Improved performance can be guaranteed by considering the reflected dynamic behaviour of the machine/tool/workpiece system. This work presents the achievable upper and lower capability bounds by introducing so-called stabilizability diagrams of a hypothetical variable pitch milling cutter that is tuned continuously along the stability boundaries. Robustly tuned milling cutters are designed for selected spindle speed ranges, which are experimentally tested both under laboratory and industrial conditions. LA - English DB - MTMT ER - TY - JOUR AU - Habib, Giuseppe AU - Kerschen, G AU - Stépán, Gábor TI - Chatter mitigation using the nonlinear tuned vibration absorber JF - INTERNATIONAL JOURNAL OF NON-LINEAR MECHANICS J2 - INT J NONLINEAR MECH VL - 91 PY - 2017 SP - 103 EP - 112 PG - 10 SN - 0020-7462 DO - 10.1016/j.ijnonlinmec.2017.02.014 UR - https://m2.mtmt.hu/api/publication/3219989 ID - 3219989 AB - A passive vibration absorber, termed the nonlinear tuned vibration absorber (NLTVA), is designed for the suppression of chatter vibrations. Unlike most passive vibration absorbers proposed in the literature for suppressing machine tool vibrations, the NLTVA comprises both a linear and a nonlinear restoring force. Its linear characteristics are tuned in order to optimize the stability properties of the machining operation, while its nonlinear properties are chosen in order to control the bifurcation behavior of the system and guarantee robustness of stable operation. In this study, the NLTVA is applied to turning machining. © 2017 Elsevier Ltd LA - English DB - MTMT ER - TY - JOUR AU - Molnár, Tamás Gábor AU - Insperger, Tamás AU - Stépán, Gábor TI - Analytical estimations of limit cycle amplitude for delay-differential equations JF - ELECTRONIC JOURNAL OF QUALITATIVE THEORY OF DIFFERENTIAL EQUATIONS J2 - ELECTRON J QUAL THEOR DIFFER EQUAT PY - 2016 IS - 77 SP - 1 EP - 10 PG - 10 SN - 1417-3875 DO - 10.14232/ejqtde.2016.1.77 UR - https://m2.mtmt.hu/api/publication/3119851 ID - 3119851 N1 - Funding Agency and Grant Number: Ministry of Human Capacities in the frame of the New National Excellence Program; Hungarian National Science Foundation [OTKA-K105433]; European Research Council under the European Union's Seventh Framework Programme / ERCEuropean Research Council (ERC) [340889] Funding text: This work has been partly financially supported by the Ministry of Human Capacities in the frame of the New National Excellence Program. The support is highly appreciated. This work was supported by the Hungarian National Science Foundation under grant OTKA-K105433. The research leading to these results has received funding from the European Research Council under the European Union's Seventh Framework Programme (FP/2007-2013) / ERC Advanced Grant Agreement n. 340889. Export Date: 29 November 2019 LA - English DB - MTMT ER - TY - JOUR AU - Dombóvári, Zoltán AU - Stépán, Gábor TI - On the bistable zone of milling processes JF - PHILOSOPHICAL TRANSACTIONS OF THE ROYAL SOCIETY A - MATHEMATICAL PHYSICAL & ENGINEERING SCIENCES J2 - PHILOS TRANS - R SOC A VL - 373 PY - 2015 IS - 2051 PG - 17 SN - 1364-503X DO - 10.1098/rsta.2014.0409 UR - https://m2.mtmt.hu/api/publication/2946918 ID - 2946918 N1 - Megjegyzés-25257315 Hiányzó Jelleg: 'JOUR\n\nArticle' Admin megjegyzés-25257315 tblcategory: (Category) ('JOUR\n\nArticle') #Jelleg Funding Agency and Grant Number: European Research Council under European Union/ERCEuropean Research Council (ERC) [340889]; EU FP7 HIPPOCAMP project [608800/FP7-2013-NMP-ICT-FOF]; Janos Bolyai Research Scholarship of the Hungarian Academy of SciencesHungarian Academy of Sciences [BO/00589/13/6]; Hungarian Scientific Research Foundation OTKAOrszagos Tudomanyos Kutatasi Alapprogramok (OTKA) [K108779] Funding text: The research leading to these results has received funding partially from the European Research Council under the European Union's Seventh Framework Programme (FP/2007-2013)/ERC Advanced grant agreement no. 340889, EU FP7 HIPPOCAMP project (608800/FP7-2013-NMP-ICT-FOF), Janos Bolyai Research Scholarship of the Hungarian Academy of Sciences (BO/00589/13/6) and the Hungarian Scientific Research Foundation OTKA grant no. K108779. Export Date: 28 November 2019 LA - English DB - MTMT ER - TY - JOUR AU - Dombóvári, Zoltán AU - Barton, David AU - Wilson, Eddie AU - Stépán, Gábor TI - On the Global Dynamics of Chatter in the Orthogonal Cutting Model JF - INTERNATIONAL JOURNAL OF NON-LINEAR MECHANICS J2 - INT J NONLINEAR MECH VL - 46 PY - 2011 IS - 1 SP - 330 EP - 338 PG - 9 SN - 0020-7462 DO - 10.1016/j.ijnonlinmec.2010.09.016 UR - https://m2.mtmt.hu/api/publication/1454448 ID - 1454448 N1 - Funding Agency and Grant Number: Hungarian Scientific Research Foundation OTKAOrszagos Tudomanyos Kutatasi Alapprogramok (OTKA) [K68910]; HAS-BUTE Research Group on Dynamics of Machines and Vehicles Hungarian-Spanish Intergovernmental S&T Cooperation Programme [OMFB-01265/2007]; OPENAER project; Great Western Research fellowship; EPSRCEngineering & Physical Sciences Research Council (EPSRC) [EP/E055567/1] Funding text: Z D and G S were supported by the Hungarian Scientific Research Foundation OTKA Grant no K68910 HAS-BUTE Research Group on Dynamics of Machines and Vehicles Hungarian-Spanish Intergovernmental S&T Cooperation Programme Grant no OMFB-01265/2007 and the OPENAER project (CENIT program of CDTI) D A W B was supported by a Great Western Research fellowship R E W was supported by EPSRC Grant EP/E055567/1 Export Date: 28 November 2019 CODEN: IJNMA Export Date: 29 November 2019 CODEN: IJNMA AB - The large-amplitude motions of a one degree-of-freedom model of orthogonal cutting are analysed. The model takes the form of a delay differential equation which is non-smooth at the instant at which the tool loses contact with the workpiece, and which is coupled to an algebraic equation that stores the profile of the cut surface whilst the tool is not in contact. This system is approximated by a smooth delay differential equation without algebraic effects which is analysed with numerical continuation software. The grazing bifurcation that defines the onset of chattering motion is thus analysed as are secondary (period-doubling, etc.) bifurcations of chattering orbits, and convergence of the bifurcation diagrams is established in the vanishing limit of the smoothing parameters. The bifurcation diagrams of the smoothed system are then compared with initial value simulations of the full non-smooth delay differential algebraic equation. These simulations mostly validate the smoothing technique and show in detail how chaotic chattering dynamics emerge from the non-smooth bifurcations of periodic orbits. © 2010 Elsevier Ltd. All rights reserved. LA - English DB - MTMT ER - TY - BOOK AU - Insperger, Tamás AU - Stépán, Gábor TI - Semi-Discretization for Time-Delay Systems. Stability and Engineering Applications TS - Stability and Engineering Applications T3 - Applied Mathematical Sciences, ISSN 0066-5452 ; 178. ET - 0 PB - Springer-Verlag London Ltd CY - New York, New York PY - 2011 SP - 174 SN - 9781461403340 DO - 10.1007/978-1-4614-0335-7 UR - https://m2.mtmt.hu/api/publication/1629264 ID - 1629264 AB - The book presents the recently introduced and already widely cited semi-discretization method for the stability analysis of delayed dynamical systems with parametric excitation. Delay-differential equations often come up in different fields of engineering, such as feedback control systems, machine tool vibrations, and balancing/stabilization with reflex delay. The behavior of such systems is often counter-intuitive and closed form analytical formulas can rarely be given even for the linear stability conditions. The same holds for parametrically excited systems. If parametric excitation is coupled with the delay effect, then the governing equation is a delay-differential equation with time-periodic coefficients, and the stability properties are even more intriguing. The semi-discretization method is a simple but efficient method that is based on the discretization with respect to the delayed term and the periodic coefficients only. This discretization results in a system of ordinary differential equations that can be solved using standard techniques, which are part of basic engineering curriculums. The method can effectively be used to construct stability charts in the space of system parameters. These charts provide a useful tool for engineers, since they present an overview on the effects of system parameters on the local dynamics of the system. The book presents the application of the method to different engineering problems, such as dynamics of turning and milling processes with constant and with varying spindle speeds, stick balancing with reflex delay, force control processes in the presence of feedback delay, and stabilization using time-periodic control gains. The book is designed for graduate and PhD students as well as researchers working in the field of delayed dynamical systems with application to mechanical, electrical and chemical engineering, control theory, biomechanics, population dynamics, neuro-physiology, and climate research. LA - English DB - MTMT ER - TY - JOUR AU - Stépán, Gábor AU - Dombóvári, Zoltán AU - Muñoa, J TI - Identification of cutting force characteristics based on chatter experiments JF - CIRP ANNALS-MANUFACTURING TECHNOLOGY J2 - CIRP ANN-MANUF TECHN VL - 60 PY - 2011 IS - 1 SP - 113 EP - 116 PG - 4 SN - 0007-8506 DO - 10.1016/j.cirp.2011.03.100 UR - https://m2.mtmt.hu/api/publication/1702990 ID - 1702990 AB - Cutting force coefficients exhibit strong nonlinearity as a function of chip loads, cutting speeds and material imperfections. This paper presents the connection between the sensitivity of the dynamics of regenerative cutting and the cutting force characteristic nonlinearity. The nonlinear milling process is mathematically modelled. The transitions of dynamic cutting process between the stable and unstable zones are considered and experimentally illustrated by applying wavelet transformations on the measurement data. © 2011 CIRP. LA - English DB - MTMT ER - TY - JOUR AU - Dombóvári, Zoltán AU - Wilson, RE AU - Stépán, Gábor TI - Estimates of the bistable region in metal cutting JF - PROCEEDINGS OF THE ROYAL SOCIETY A: MATHEMATICAL PHYSICAL AND ENGINEERING SCIENCES J2 - PROC A MATH PHYS ENG SCI VL - 464 PY - 2008 SP - 3255 EP - 3271 PG - 17 SN - 1364-5021 DO - 10.1098/rspa.2008.0156 UR - https://m2.mtmt.hu/api/publication/1139887 ID - 1139887 N1 - Admin megjegyzés-24789510 #JournalID1# Name: Proceedings of the Royal Society A: Mathematical, Physical and Engineering Science ISSN: 1364-5021 #JournalID2# AB - The classical model of regenerative vibration is investigated \nwith new kinds of nonlinear cutting force characteristics. The \nstandard nonlinear characteristics are subjected to a critical \nreview from the nonlinear dynamics viewpoint based on the \nexperimental results available in the literature. The proposed \nnonlinear model includes finite derivatives at zero chip \nthickness and has an essential inflexion point. In the case of \nthe one degree-of-freedom model of orthogonal cutting, the \nexistence of unstable self-excited vibrations is proven along \nthe stability limits, which is strongly related to the force \ncharacteristic at its inflexion point. An analytical estimate is \ngiven for a certain area below the stability limit where stable \nstationary cutting and a chaotic attractor coexist. It is shown \nhow this domain of bistability depends on the theoretical chip \nthickness. The comparison of these results with the experimental \nobservations and also with the subcritical Hopf bifurcation \nresults obtained for standard nonlinear cutting force \ncharacteristics provides relevant information on the nature of \nthe cutting force nonlinearity. LA - English DB - MTMT ER - TY - JOUR AU - Szalai, R AU - Stépán, Gábor AU - Hogan, SJ TI - Global dynamics of low immersion high-speed milling JF - CHAOS J2 - CHAOS VL - 14 PY - 2004 IS - 4 SP - 1069 EP - 1077 PG - 9 SN - 1054-1500 DO - 10.1063/1.1807395 UR - https://m2.mtmt.hu/api/publication/106039 ID - 106039 LA - English DB - MTMT ER - TY - JOUR AU - Kalmár-Nagy, Tamás AU - Stépán, Gábor AU - Moon, FC TI - Subcritical Hopf bifurcation in the delay equation model for machine tool vibrations JF - NONLINEAR DYNAMICS J2 - NONLINEAR DYNAM VL - 26 PY - 2001 IS - 2 SP - 121 EP - 142 PG - 22 SN - 0924-090X DO - 10.1023/A:1012990608060 UR - https://m2.mtmt.hu/api/publication/106051 ID - 106051 N1 - Export Date: 29 November 2019 CODEN: NODYE AB - We show the existence of a subcritical Hopf bifurcation in the delay-differential equation model of the so-called regenerative machine tool vibration. The calculation is based on the reduction of the infinite-dimensional problem to a two-dimensional center manifold. Due to the special algebraic structure of the delayed terms in the nonlinear part of the equation, the computation results in simple analytical formulas. Numerical simulations gave excellent agreement with the results. LA - English DB - MTMT ER - TY - BOOK AU - Stépán, Gábor TI - Retarded Dynamical Systems. Stability and Characteristic Functions TS - Stability and Characteristic Functions T3 - Pitman Research Notes in Mathematics Series ; 210. ET - 0 PB - Longman Scientific and Technical CY - Harlow PY - 1989 SP - 151 SN - 0470213353 UR - https://m2.mtmt.hu/api/publication/1002286 ID - 1002286 N1 - co-published: Wiley, New York LA - English DB - MTMT ER -