Vibration control and electricity generating device using a number of hula-hoops and generators

This paper deals with the vibration control device which simultaneously generates electricity by using absorbed vibration energy. This device consists of a hula-hoop and a generator. In this paper, we researched the case of using a number of devices. As the result of the experiment and the numerical calculation, the following points were made clear: (1) When two devices are used, the component of the centrifugal forces which are perpendicular to the direction of the external force are cancelled by rotating two hula-hoops in opposite directions. Moreover, the optimum quenching according to the amplitude of the external force is possible by varying the number of rotating hula-hoops. (2) The operating curve was shown by composing the resonance curves when the hula-hoops rotate and those when they do not. (3) The amount of generated electric power is proportional to the second power of the external frequency. (4) The experimental and the numerical results were in good qualitative agreement with each other.