title: S-shape spring sensor: Sensing specific low-frequency vibration by energy harvesting.
abstract: We have developed a Si-based microelectromechanical systems sensor with high sensitivity for specific low-frequency vibration-sensing and energy-harvesting applications. The low-frequency vibration sensor contains a disk proof mass attached to two or three lead zirconate titanate (PZT) S-shape spring flexures. To obtain a faster and less expensive prototype, the design and optimization of the sensor structure are studied via finite-element method analysis. To validate the sensor structure to detect low-frequency vibration, the effects of geometrical dimensions, including the width and diameter of the S-shape spring of the proof mass, were analyzed and measured. The functional features, including the mechanical property and electrical performance of the vibration sensor, were evaluated. The results demonstrated that a very low resonant frequency of <11 Hz and a reasonably high voltage output of 7.5 mV at acceleration of >0.2g can be typically achieved. Given a low-frequency vibration sensor with ideal performance and mass fabrication, many advanced civilian and industrial applications can be possibly realized.
authors: Research Center for Ubiquitous MEMS and Micro Engineering (UMEMSME), National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba, Ibaraki 305-8564, Japan.
authors: Lan
authors: L
authors: Zhang
authors: Research Center for Ubiquitous MEMS and Micro Engineering (UMEMSME), National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba, Ibaraki 305-8564, Japan.
authors: Jian
authors: J
authors: Lu
authors: Research Center for Ubiquitous MEMS and Micro Engineering (UMEMSME), National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba, Ibaraki 305-8564, Japan.
authors: Ryohei
authors: R
authors: Takei
authors: Research Center for Ubiquitous MEMS and Micro Engineering (UMEMSME), National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba, Ibaraki 305-8564, Japan.
authors: Natsumi
authors: N
authors: Makimoto
authors: Research Center for Ubiquitous MEMS and Micro Engineering (UMEMSME), National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba, Ibaraki 305-8564, Japan.
authors: Toshihiro
authors: T
authors: Itoh
authors: Research Center for Ubiquitous MEMS and Micro Engineering (UMEMSME), National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba, Ibaraki 305-8564, Japan.
authors: Takeshi
authors: T
authors: Kobayashi