The space sheet for a solar array structure is large in dimension, and flexible to induce complex distortion. It is difficult to measure the distortion. A large-scale flexible test prototype system is built for sheet ...The space sheet for a solar array structure is large in dimension, and flexible to induce complex distortion. It is difficult to measure the distortion. A large-scale flexible test prototype system is built for sheet structure vibration monitoring based on the vibration information of the solar array in space. The system provides an intelligent test method for flexible space structure with embedded sensors and non-visualization reinstruction. Multiple fiber Bragg grating （FBG） sensors are packaged and embedded into the structure with spatial division multiplexing （SDM） and wavelength division multiplexing （WDM）. The sensor interrogator distinguishes wavelength shifts that can be turned into curvature of the curve. The structure shape is reconstructed based on the curvature information and the arc-length, and then displayed. The experiment shows that the system has a high FBG sensitivity. The reconstruction algorithm is fast with high precision. The system has great potential for use in health monitoring of the space sheet structure.展开更多
This article studies the dielectric and piezoelectric behavior of unpoled and poled barium titanate(BaTiO_(3))polycrystals with oxygen vacancies.A phase field model is employed for BaTiO_(3) polycrystals,coupled with ...This article studies the dielectric and piezoelectric behavior of unpoled and poled barium titanate(BaTiO_(3))polycrystals with oxygen vacancies.A phase field model is employed for BaTiO_(3) polycrystals,coupled with the time-dependent Ginzburg–Landau theory and the oxygen vacancies diffusion,to demonstrate the interaction between oxygen vacancies and domain evolutions.To generate grain structures,the phase field model for grain growth is also used.The hysteresis loop and butterfly curve are predicted at room and high temperatures.The permittivity,and longitudinal and transverse piezoelectric constants of the BaTiO_(3) polycrystals are then examined for various grain sizes and oxygen vacancy densities.展开更多
This paper presents the nonlinear electromagneto-mechanical behavior of magnetostrictive/piezoelectric laminates under three-point bending both numerically and experimentally.The laminates are fabricated using thin Te...This paper presents the nonlinear electromagneto-mechanical behavior of magnetostrictive/piezoelectric laminates under three-point bending both numerically and experimentally.The laminates are fabricated using thin Terfenol-D and PZT layers.The three-point bending test was conducted on the Terfenol-D/PZT laminates,and the displacement,induced magnetic field and induced voltage due to mechanical loads were measured.Three-dimensional finite element analysis was also carried out,and the electromagneto-mechanical fields in the laminates were predicted by introducing a second-order magnetoelastic constant for Terfenol-D.Comparison was then made between simulation and experiment.展开更多
基金Project supported by the National Natural Science Foundation China (Grant No.90405013)
文摘The space sheet for a solar array structure is large in dimension, and flexible to induce complex distortion. It is difficult to measure the distortion. A large-scale flexible test prototype system is built for sheet structure vibration monitoring based on the vibration information of the solar array in space. The system provides an intelligent test method for flexible space structure with embedded sensors and non-visualization reinstruction. Multiple fiber Bragg grating （FBG） sensors are packaged and embedded into the structure with spatial division multiplexing （SDM） and wavelength division multiplexing （WDM）. The sensor interrogator distinguishes wavelength shifts that can be turned into curvature of the curve. The structure shape is reconstructed based on the curvature information and the arc-length, and then displayed. The experiment shows that the system has a high FBG sensitivity. The reconstruction algorithm is fast with high precision. The system has great potential for use in health monitoring of the space sheet structure.
基金This work was supported by JSPS KAKENHI Grant Number 16H04227.
文摘This article studies the dielectric and piezoelectric behavior of unpoled and poled barium titanate(BaTiO_(3))polycrystals with oxygen vacancies.A phase field model is employed for BaTiO_(3) polycrystals,coupled with the time-dependent Ginzburg–Landau theory and the oxygen vacancies diffusion,to demonstrate the interaction between oxygen vacancies and domain evolutions.To generate grain structures,the phase field model for grain growth is also used.The hysteresis loop and butterfly curve are predicted at room and high temperatures.The permittivity,and longitudinal and transverse piezoelectric constants of the BaTiO_(3) polycrystals are then examined for various grain sizes and oxygen vacancy densities.
基金supported by Grant-in-Aid for JSPS Fellows(22·3402).
文摘This paper presents the nonlinear electromagneto-mechanical behavior of magnetostrictive/piezoelectric laminates under three-point bending both numerically and experimentally.The laminates are fabricated using thin Terfenol-D and PZT layers.The three-point bending test was conducted on the Terfenol-D/PZT laminates,and the displacement,induced magnetic field and induced voltage due to mechanical loads were measured.Three-dimensional finite element analysis was also carried out,and the electromagneto-mechanical fields in the laminates were predicted by introducing a second-order magnetoelastic constant for Terfenol-D.Comparison was then made between simulation and experiment.
