Chaotic vibrations in a regenerative cutting process

We have analyzed vibrations generated in an orthogonal cutting process. Using a simple one degree of freedom model of the regenerative cutting we have observed the complex behaviour of the system. In presence of a shaped cutting surface, the nonlinear interaction between the tool and a worpiece leads to chatter vibrations of periodic, quasi-periodic or chaotic type depending on system parameters. To describe the profile of the surface machined by the first pass we used a harmonic function. We analysed the impact phenomenon between the tool and a workpiece after their contact loss.Comment: 7 pages, 3 figure

Resonances of the SD oscillator due to the discontinuous phase

Resonance phenomena of a harmonically excited system with mul-tiple potential well play an important role in nonlinear dynamics research.In this paper, we investigate the resonant behaviours of a discontinuous dynamical system with double well potential derived from the SD oscillator to gain better understanding of the transition of resonance mechanism. Firstly,the time dependent Hamiltonian is obtained for a Duffing type discontinuous system modelling snap-through buckling. This system comprises two subsystems connected at x = 0, for which the system is discontinuous. We constructa series of generating functions and canonical transformations to obtain the canonical form of the system to investigate the complex resonant behavioursof the system. Furthermore, we introduce a composed winding number to explore complex resonant phenomena. The formulation for resonant phenomena given in this paper generalizes the formulation of n Omega0 = m Omega used in the regular perturbation theory, where n and m are relative prime integers, Omega 0 and Omega are the natural frequency and external frequencies respectively. Understanding the resonant behaviour of the SD oscillator at the discontinuousphase enables us to further reveal the vibrational energy transfer mechanism between smooth and discontinuous nonlinear dynamical system

Bifurcation and dynamic response analysis of rotating blade excited by upstream vortices

Acknowledgements The authors acknowledge the projects supported by the National Basic Research Program of China (973 Project)(No. 2015CB057405) and the National Natural Science Foundation of China (No. 11372082) and the State Scholarship Fund of CSC. DW thanks for the hospitality of the University of Aberdeen.Peer reviewedPostprin

Experimental Investigation of the Vibro-impact Capsule System

Dr. Yang Liu would like to acknowledge the financial support for the Small Research Grant (31841) by the Carnegie Trust for the Universities of Scotland. This work is also partially supported by the National Natural Science Foundation of China (Grant Nos. 11672257 and 11402224), the Natural Science Foundation of Jiangsu Province of China (Grant No. BK20161314).Peer reviewedPublisher PD

Basins of attraction of the bistable region of time-delayed cutting dynamics

This research is supported by National Natural Science Foundation of China under Grant No. 11502048 and 11572224, and Fundamental Research Funds for the Central Universities under Grant No.ZYGX2015KYQD033.Peer reviewedPublisher PD

Experimental studies of the resultant contact forces in drillbit-rock interaction

Peer reviewedPostprin

Path-following analysis of the dynamical response of a piecewise-linear capsule system

Acknowledgements The first author has been supported by a Georg Forster Research Fellowship granted by the Alexander von Humboldt Foundation, GermanyPeer reviewedPreprin

Global dynamics of a harmonically excited oscillator with a play : Numerical studies

This work was supported by the National Secretariat of Science, Technology and Innovation of Ecuador (SENESCYT); the Escuela Superior Politécnica del Litoral of Ecuador (ESPOL); the National Natural Science Foundation of China (11272268, 11572263) and Scholarship of China. A.S.E. Chong and Y. Yue acknowledge the hospitality of the Centre of Applied Dynamics Research at the University of Aberdeen.Peer reviewedPostprin

Regenerative chatter in self-interrupted plunge grinding

This research is supported by National Natural Science Foundation of China under Grant Nos.11572224 and 11502048, and Fundamental Research Funds for the Central Universities under Grant No. ZYGX2015KYQD033. We would like to thank Dr. Pankaj Wahi for an initial discussion during YY’s stay in Aberdeen.Peer reviewedPublisher PD