概要

Name: Takehiko Asai
Affiliation: Faculty of Engineering, Information and Systems
Specialty: Division of Engineering Mechanics and Energy
Field of Research: Structural Control
Position: Assistant Professor
Degree:

Ph.D. in Civil Engineering

Degree earning University : University of Illinois at Urbana-Champaign (May 2014)
Starting Date: January 1, 2016
Mentor: Professor Yuki Sakai
Laboratory:

http://www.kz.tsukuba.ac.jp/~asai/index_e.html

Development of self-powered structural control systems

 Japan has suffered severe damage from recurring earthquakes in the past. We have to use these experiences as a lesson, and we need to improve structural control technologies in buildings and bridges to protect human lives, properties, and stuff from expected earthquakes such as Tokai, Nankai, and Tonankai with high probability in the near future.
 One of the structural control methods for civil structures subject to earthquake loadings is active control, in which the control forces are injected into the structure through actuators. These actuators are activated by employing external power sources, however the external power grid is generally deemed unreliable during seismic events.
 To address this issue, one of my research interests lies in developing self-powered structural control systems. Generally, in civil structures, the input energy is converted to heat energy and the vibration reduction can be accomplished. While, a self-powered vibration control system is comprised of vibratory energy harvesting technologies which convert vibratory mechanical energy to electrical energy by electromechanical transducers. Then the harvested energy can be reinjected to the structure as control forces, which leads to further vibration reduction.
 Also, the possibilities of the energy harvesting technology in high-rise buildings and bridges subject to strong winds and buoys subject to tidal waves are explored. And I would like to mature this technology enough to play a key role in realizing so-called smart cities and sustainable cities.
 My work focuses on the development of mechanism and feedback control theory to optimize the energy harvesting and vibration reduction performances and on the validation through numerical simulations and experiments.