Abstract
This paper introduces a newly designed pendulum system that enables the more accurate boservation of dynamic behaviour arising from both horizontal and vertical(i.e. two dimension) excitation. First, experiments were carried out to examine the frequency responses of the devised pendulum system. Interestingly, experimental results for the three excitation angles of 22, 32 and 48 degree show 'new' jump phenomena. For the further understanding of these phenomena, experimental investigationhas been made to identify the equation of motion of the pendulum system from experimental data. This attempt has revealed that the viscous, coulomb and aerodynamic damping factors are involved in the equation of motion. By applying the Ritz averaging method to the equation, it becomes apparent that the jumping phenomena of the pendulum system in this work is more theoretically understood.