Dynamic interactions between parametric pendulum and electrodynamical shaker

In this paper we investigate the dynamic interactions between a parametric pendulum and an electro-dynamical shaker aiming to explain a weak correlation between the theoretical predictions obtained for a parametric pendulum model and the experimental results for pendulum rig driven by the shaker. In particular, the quasi-periodic rotations were found experimentally to be co-existing with the period one rotations, where no such motion can be predicted for parametric pendulum with an ideal parametric excitation. First the experimental setup including the pendulum, the shaker and data acquisition system is described. Then the electro-dynamical shaker is modelled as two and a half degrees-of-freedom system. Next the parameters of the system have been identified by static and dynamic tests. Finally, comparisons between theoretical and experimental results were made for the pendulum–shaker system and a good agreement was obtained for a wide range of the system parameters.