چكيده لاتين :
This paper describes a preliminary investigation into the use of normal form
theory for modelling large non-linear dynamic systems. Limit cycle oscillations
are determined for simple two-degree-of-freedom double pendulum systems.
Such a system is reduced into its centre manifold before computation of normal
forms, which are obtained using a period averaging method applicable to 71071autonomous
systems and more advantageous than the classical methods. A
good agreement was observed between the predicted results from the normal
form theory and the numerical simulations of the original system.
