CHAOS IN A MECHANISM WITH TIME DELAYS UNDER PARAMETRIC AND EXTERNAL EXCITATION

Large motions of a one-degree-of-freedom mechanism are analyzed. The mechanism has two stable equilibrium states and an unstable one. It is subjected to a harmonic parametric excitation and an external excitation with one or two harmonic components. A dashpot and a non-linear spring are attached to the mechanism. In some cases the dashpot or spring force has a time delay in its action. The large-time response of the model is determined by numerical integration. It is found that the response may be periodic, chaotic, or unbounded. When it is periodic, its period is compared to that of the excitation.