Basic development of inverted pendulum type power generator based on autoparametric resonance for low frequency

In this report, as the environmental power generation and wave power generation device, inverted pendulum type power generator based on autoparametric resonance is devised. Theoretical study and experimental verification of proposed device were performed. The autoparametric resonance is an unstable vibration generated by nonlinear coupling between the main system and the subsystem in which the vibration directions of two degrees of freedom or more are orthogonal [1]. The purpose of this research is to develop a system which converts vibration external force of low frequency band to high efficiency for rotation of pendulum using this autoparametric excitation. A model of a two degree of freedom system composed of an inverted pendulum supported by a spring system, and a mass-spring system was devised. Approximate analysis and shooting method were used to calculate the amplitude of the main resonance and the amplitude of the pendulum in each system. We examined the influence of parameters theoretically. Experiments using model device were also conducted to verify the validity of the theoretical results.