TY - JOUR AU - Lelkes, János AU - Kalmár-Nagy, Tamás TI - A Nonlinear Delay-Differential Equation with Harmonic Excitation JF - IFAC PAPERSONLINE J2 - IFACOL VL - 51 PY - 2018 IS - 14 SP - 224 EP - 229 PG - 6 SN - 2405-8971 DO - 10.1016/j.ifacol.2018.07.227 UR - https://m2.mtmt.hu/api/publication/3422139 ID - 3422139 N1 - Cited By :1 Export Date: 9 July 2024 AB - A machining tool can be subject to different kinds of excitations. The forcing may have external sources (such as rotating imbalance or misalignment of the workpiece) or it can arise from the cutting process itself (e.g. chip formation). We investigate the classical tool vibration model which is a delay-differential equation with a quadratic and cubic nonlinearity and periodic forcing. The method of multiple scales gave an excellent approximation of the solution. The resonance curves found here are similar to those for the Duffing-equation, having a hardening characteristic. We found subcritical Hopf and saddle-node bifurcations. (C) 2018, IFAC (International Federation of Automatic Control) Hosting by Elsevier Ltd. All rights reserved. LA - English DB - MTMT ER - TY - CHAP AU - Lelkes, János AU - Kalmár-Nagy, Tamás ED - Serban, Radu TI - Harmonically Excited Delay Equation for Machine Tool Vibrations T2 - ASME 2018 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference PB - American Society of Mechanical Engineers (ASME) CY - New York, New York SN - 9780791851838 ET - 0 PY - 2018 PG - 7 DO - 10.1115/DETC2018-86145 UR - https://m2.mtmt.hu/api/publication/30309643 ID - 30309643 N1 - Cited By :1 Export Date: 9 July 2024 AB - A machining tool can be subject to different kinds of excitations. The forcing may have external sources (such as rotating imbalance or misalignment of the workpiece) or it can arise from the cutting process itself (e.g. chip formation). We investigate the classical tool vibration model which is a delay-differential equation with a quadratic and cubic nonlinearity and periodic forcing. The method of multiple scales was used to derive the slow flow equations. The resonance curves of the system are similar to those for the Duffing-equation, having a hardening characteristic. Stability analysis for the fixed points of the slow-flow equations was performed. Local and global bifurcations were studied and illustrated with phase portraits and direct numerical integration of the original equation. Subcritical Hopf saddle-node and heteroclinic bifurcations were found. LA - English DB - MTMT ER - TY - JOUR AU - Molnár, Tamás Gábor AU - Dombóvári, Zoltán AU - Insperger, Tamás AU - Stépán, Gábor TI - On the analysis of the double Hopf bifurcation in machining processes via center manifold reduction JF - PROCEEDINGS OF THE ROYAL SOCIETY A: MATHEMATICAL PHYSICAL AND ENGINEERING SCIENCES J2 - PROC A MATH PHYS ENG SCI VL - 473 PY - 2017 IS - 2207 PG - 20 SN - 1364-5021 DO - 10.1098/rspa.2017.0502 UR - https://m2.mtmt.hu/api/publication/3273043 ID - 3273043 N1 - Megjegyzés-27107587 Admin megjegyzés-27207957 #JournalID1# Name: PROCEEDINGS OF THE ROYAL SOCIETY A-MATHEMATICAL PHYSICAL AND ENGINEERING SCIENCES ISSN: 1364-5021 #JournalID2# Export Date: 29 November 2019 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 N1 - Cited By :204 Export Date: 9 July 2024 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 - Liu, Liping AU - Kalmár-Nagy, Tamás TI - High-dimensional harmonic balance analysis for second-order delay-differential equations JF - JOURNAL OF VIBRATION AND CONTROL J2 - J VIB CONTROL VL - 16 PY - 2010 IS - 7-8 SP - 1189 EP - 1208 PG - 20 SN - 1077-5463 DO - 10.1177/1077546309341134 UR - https://m2.mtmt.hu/api/publication/2827251 ID - 2827251 N1 - Cited By :52 Export Date: 9 July 2024 CODEN: JVCOF Correspondence Address: Liu, L.; Department of Mathematics, , Greensboro, NC 27411, United States; email: liping.liu@ncat.edu LA - English DB - MTMT ER - TY - BOOK ED - Balachandran, Balakumar ED - Kalmár-Nagy, Tamás ED - Gilsinn, David TI - Delay Differential Equations: Recent Advances and New Directions ET - 1 PB - Springer Science+Business Media CY - New York, New York PY - 2009 SP - 350 SN - 9781441946690 DO - 10.1007/978-0-387-85595-0 UR - https://m2.mtmt.hu/api/publication/30178324 ID - 30178324 N1 - Table of contents: http://www.gbv.de/dms/bowker/toc/9780387855943.pdf Additional information: http://www.loc.gov/catdir/enhancements/fy1315/2008935618-d.html http://www.loc.gov/catdir/enhancements/fy1315/2008935618-t.html http://zbmath.org/?q=an:1162.34003 AB - Delay Differential Equations: Recent Advances and New Directions cohesively presents contributions from leading experts on the theory and applications of functional and delay differential equations (DDEs). Students and researchers will benefit from a unique focus on theory, symbolic, and numerical methods, which illustrate how the concepts described can be applied to practical systems ranging from automotive engines to remote control over the Internet. Comprehensive coverage of recent advances, analytical contributions, computational techniques, and illustrative examples of the application of current results drawn from biology, physics, mechanics, and control theory. Students, engineers and researchers from various scientific fields will find Delay Differential Equations: Recent Advances and New Directions a valuable reference. LA - English DB - MTMT ER - TY - JOUR AU - Csernák, Gábor AU - Pálmay, Zoltán TI - Exploration of the chaotic phenomena induced by fast plastic deformation of metals JF - INTERNATIONAL JOURNAL OF ADVANCED MANUFACTURING TECHNOLOGY J2 - INT J ADV MANUFACT TECHNOL VL - 40 PY - 2009 IS - 3-4 SP - 270 EP - 276 PG - 7 SN - 0268-3768 DO - 10.1007/s00170-007-1348-6 UR - https://m2.mtmt.hu/api/publication/1114361 ID - 1114361 LA - English DB - MTMT ER - TY - JOUR AU - Pálmay, Zoltán AU - Csernák, Gábor TI - Chip formation as an oscillator during the turning process JF - JOURNAL OF SOUND AND VIBRATION J2 - J SOUND VIB VL - 326 PY - 2009 IS - 3-5 SP - 809 EP - 820 PG - 12 SN - 0022-460X DO - 10.1016/j.jsv.2009.05.028 UR - https://m2.mtmt.hu/api/publication/2669924 ID - 2669924 N1 - Funding Agency and Grant Number: Hungarian National Science Foundation [OTKA F049242]; Janos Bolyai Research ScholarshipHungarian Academy of Sciences; Hungarian Academy of SciencesHungarian Academy of Sciences Funding text: This research project was supported by the Hungarian National Science Foundation under Grant no. OTKA F049242, and by the Janos Bolyai Research Scholarship of the Hungarian Academy of Sciences. The authors thank Dr. JAnos KodScsy (Kecskemet College, Faculty of Technology (GAMF) for his help with the experimental examination of the nonlinear dynamics of the cutting process. Export Date: 29 November 2019 CODEN: JSVIA 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 - CHAP AU - Stépán, Gábor ED - Moon, FC TI - Delay-differential equation models for machine tool chatter T2 - Dynamics and Chaos in Manufacturing Processes PB - John Wiley & Sons CY - New York, New York SN - 0471152935 PY - 1998 SP - 165 EP - 192 PG - 28 UR - https://m2.mtmt.hu/api/publication/1002656 ID - 1002656 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 -