210404 弦で拘束された弓状はりのカオス振動利用による動吸振器の実験(OS14 非線形振動,オーガナイズド・セッション)

抄録

A new type of vibration-absorber is proposed using the characteristics of chaotic response generated by a bowed-type beam constrained with stretched strings. The bowed-typed beam is clamped at the center and deformed to a curved configuration by stretched strings which connect both ends of the beam. An elastic structure, which is the target of vibration-suppression, consists of moving block and spring plates. The bowed-type beam is mounted on the elastic structure to decrease the vibration-amplitude on the structure. In the experiment, the structure is excited by an electromagnetic shaker through a ring-spring. Non-periodic responses are generated on the vibration-absorber in a finite region of excitation frequency, then the vibration-amplitude of the structure is suppressed sufficiency. To confirm the mechanism of the vibration-absorber, Non-periodic responses are examined by the Fourier spectrum, the maximum Lyapunov exponent and the Principal Component Analysis. It is found that the vibration-amplitude on the structure with the vibration-absorber is decreased by chaotic response of the absorber.