TY - JOUR
T1 - A vibration energy harvesting device with bidirectional resonance frequency tunability
AU - Challa, Vinod R.
AU - Prasad, M. G.
AU - Shi, Yong
AU - Fisher, Frank T.
PY - 2008/2/1
Y1 - 2008/2/1
N2 - Vibration energy harvesting is an attractive technique for potential powering of wireless sensors and low power devices. While the technique can be employed to harvest energy from vibrations and vibrating structures, a general requirement independent of the energy transfer mechanism is that the vibration energy harvesting device operate in resonance at the excitation frequency. Most energy harvesting devices developed to date are single resonance frequency based, and while recent efforts have been made to broaden the frequency range of energy harvesting devices, what is lacking is a robust tunable energy harvesting technique. In this paper, the design and testing of a resonance frequency tunable energy harvesting device using a magnetic force technique is presented. This technique enabled resonance tuning to 20% of the untuned resonant frequency. In particular, this magnetic-based approach enables either an increase or decrease in the tuned resonant frequency. A piezoelectric cantilever beam with a natural frequency of 26Hz is used as the energy harvesting cantilever, which is successfully tuned over a frequency range of 22-32Hz to enable a continuous power output 240-280νW over the entire frequency range tested. A theoretical model using variable damping is presented, whose results agree closely with the experimental results. The magnetic force applied for resonance frequency tuning and its effect on damping and load resistance have been experimentally determined.
AB - Vibration energy harvesting is an attractive technique for potential powering of wireless sensors and low power devices. While the technique can be employed to harvest energy from vibrations and vibrating structures, a general requirement independent of the energy transfer mechanism is that the vibration energy harvesting device operate in resonance at the excitation frequency. Most energy harvesting devices developed to date are single resonance frequency based, and while recent efforts have been made to broaden the frequency range of energy harvesting devices, what is lacking is a robust tunable energy harvesting technique. In this paper, the design and testing of a resonance frequency tunable energy harvesting device using a magnetic force technique is presented. This technique enabled resonance tuning to 20% of the untuned resonant frequency. In particular, this magnetic-based approach enables either an increase or decrease in the tuned resonant frequency. A piezoelectric cantilever beam with a natural frequency of 26Hz is used as the energy harvesting cantilever, which is successfully tuned over a frequency range of 22-32Hz to enable a continuous power output 240-280νW over the entire frequency range tested. A theoretical model using variable damping is presented, whose results agree closely with the experimental results. The magnetic force applied for resonance frequency tuning and its effect on damping and load resistance have been experimentally determined.
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U2 - 10.1088/0964-1726/17/01/015035
DO - 10.1088/0964-1726/17/01/015035
M3 - Article
AN - SCOPUS:41849138249
SN - 0964-1726
VL - 17
JO - Smart Materials and Structures
JF - Smart Materials and Structures
IS - 1
M1 - 015035
ER -