RT Journal Article
SR Electronic
T1 The use of normal forms for analysing nonlinear mechanical vibrations
JF Philosophical Transactions of the Royal Society A: Mathematical,
Physical and Engineering Sciences
JO Philos Transact A Math Phys Eng Sci
FD The Royal Society
DO 10.1098/rsta.2014.0404
VO 373
IS 2051
A1 Neild, Simon A.
A1 Champneys, Alan R.
A1 Wagg, David J.
A1 Hill, Thomas L.
A1 Cammarano, Andrea
YR 2015
UL http://rsta.royalsocietypublishing.org/content/373/2051/20140404.abstract
AB A historical introduction is given of the theory of normal forms for simplifying nonlinear dynamical systems close to resonances or bifurcation points. The specific focus is on mechanical vibration problems, described by finite degree-of-freedom second-order-in-time differential equations. A recent variant of the normal form method, that respects the specific structure of such models, is recalled. It is shown how this method can be placed within the context of the general theory of normal forms provided the damping and forcing terms are treated as unfolding parameters. The approach is contrasted to the alternative theory of nonlinear normal modes (NNMs) which is argued to be problematic in the presence of damping. The efficacy of the normal form method is illustrated on a model of the vibration of a taut cable, which is geometrically nonlinear. It is shown how the method is able to accurately predict NNM shapes and their bifurcations.