Simultaneous vibration suppression and energy harvesting with a non-traditional vibration absorber

Abstract

The dynamic vibration absorber, or tuned mass damper, has been one of the most commonly used passive vibration control devices over the past hundred years. With an optimally designed vibration absorber, significant vibration suppression can be achieved to maintain structure health and integrity. On the other hand, researchers are seeking effective energy harvesting techniques to harvest energy from ambient vibration for purposes such as powering sensor networks and microsystems. This has brought light to the investigation of simultaneous vibration suppression and energy harvesting. This research is thus motivated to develop an apparatus with a non-traditional vibration absorber in order to achieve vibration control and energy harvesting simultaneously. For a traditional vibration absorber installed to a single-degree-of-freedom primary system, the absorber damper is connected between the primary mass and the absorber mass. The tuning strategies of such a traditional absorber have been thoroughly studied and energy harvesting techniques have also been applied to the combined system. This research studies a non-traditional vibration absorber whose absorber damper is connected directly between the absorber mass and the base. An apparatus is developed in which an electromagnetic damper used as both the absorber damper and energy harvester is placed between the absorber mass and the base. The principle of the electromagnetic damping is discussed, and the optimum parameters of the non-traditional vibration absorber are studied with respect to different performance indexes under various types of excitation. Analytical derivation, numerical simulation and experiment results are presented in the investigation of each of the tuning strategies. The study has indicated that despite the inevitable trade-off between vibration suppression and energy harvesting, the proposed apparatus is capable of achieving the dual goal with a satisfying performance.