International Journal of Applied Electromagnetics and Mechanics - Volume 52, issue 3-4

Authors: Wu, Chengsong | Xu, Minglong | Wu, Tonghui | Ma, Guoliang

Article Type: Research Article

Abstract: Panel reflection antenna in large diameter is a typical cantilever structure and has the quality of low-stiffness, weak-damping and flexible-significantly. Large amplitude and enduring vibration will occur when satellite adjusts posture due to frequency coupling, which will greatly affect pointing accuracy of the antenna. In this paper, four Macro Fiber Composite (MFC) patches are applied as sensors and actuators to control the coupling vibration of the antenna. PD and fuzzy control algorithms are utilized to build the closed-loop feedback control system. Active vibration control of the first two vibration modes in both free attenuation vibration situation and steady excitation vibration …situation are implemented. The experiment results suggest that using MFC sensors and actuators in active vibration control of the antenna is effective. Show more

Keywords: Active vibration control, panel reflection antenna, MFC sensors and actuators

DOI: 10.3233/JAE-162157

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 52, no. 3-4, pp. 1267-1275, 2016

Authors: Zhang, Shuai | Zhang, Yahong | Zhang, Xinong | Zheng, Yisheng

Article Type: Research Article

Abstract: This paper deals with the vibration control of a doubly curved shell by Macro-Fiber Composite (MFC) piezoelectric actuator. The driving force and bending moment formulas of MFC actuator are derived based on the constitutive relations of the piezoelectric material and bending deformation theory. The vibration of the doubly curved shell under fuzzy PID control is simulated. Results show that using fuzzy PID controller can effectively suppress the vibration of the system. Compared with classical PID controller, the fuzzy PID controller shows better performance, faster response and stronger robustness.

Keywords: Doubly curved shell, MFC actuator, vibration control, fuzzy PID control

DOI: 10.3233/JAE-162176

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 52, no. 3-4, pp. 1277-1286, 2016

Authors: Su, Daniel | Li, Xiang | Luo, Yun

Article Type: Research Article

Abstract: Prosthesis is an important means of compensatory morphological and functional way to help extremity disabled patients in rehabilitation and reintegration. As the human-machine interface (HMI) in between the prosthesis and the stump, compatibility of the prosthetic socket liner interface greatly influence whether the amputee abandoned artificial limbs or not. Base on complaint bistable mechanism and 3D printing technology, this paper presents a bionic elastomer design of prosthetic socket liner. Compatible flexible continuum structure has interface design to achieving anisotropy mechanical force properties.

Keywords: Prosthetic socket, silicone liner, human-machine interface (HMI), anisotropy, 3D printing, bionic, elastomer, passive structure, complaint bistable mechanism

DOI: 10.3233/JAE-162074

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 52, no. 3-4, pp. 1287-1293, 2016

Authors: Liang, Qinghua | Mo, Jinqiu | Dai, Xin | Long, Yongjun | Cao, Jiayong | Wang, Shigang

Article Type: Research Article

Abstract: This paper presents a two-dimensional (2D) analytical model for predicting the magnetic field in field modulated permanent-magnet (PM) eddy-current couplings with a slotted conductor rotor. Based on the subdomain method, the original radial-flux model with a cylindrical geometry is simplified and analyzed in Cartesian coordinates to solve the moving conductor eddy current problem, avoiding the complicated computation with Bessel function in cylindrical or polar coordinates. In the process of modeling, the effects of the field modulation on the eddy currents, the influence of eddy current reaction field on the air gap field, and the interactions between the adjacent conducting bars …are considered. The moving PM field is treated as a source of a time-harmonic field and the diffusion equations in the bars are simplified and converted to complex temporal Hemholtz functions. The comparison of analytical and nonlinear finite element analysis results shows the effectiveness of the proposed analytical model. Show more

Keywords: Eddy current coupling, field modulation, radial flux

DOI: 10.3233/JAE-162135

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 52, no. 3-4, pp. 1295-1303, 2016

Authors: Nowacki, J.P. | Drabik, A. | Alshits, V.I.

Article Type: Research Article

Abstract: Electroelastic 2D fields excited by a straight general line source in an anisotropic periodically layered piezoelectric medium are expressed in an implicit analytical form of well-convergent Fourier integral. The analysis is given in terms of the 8 × 8 propagator matrix constructed for a graded or stratified medium formed by a periodic succession of layers. The general line source represents a combination of the straight 4D dislocation with the force and charge distributed along the same line.

Keywords: Piezoelectricity, anisotropy, 1D inhomogeneity, periodic multilayers, general line source

DOI: 10.3233/JAE-162079

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 52, no. 3-4, pp. 1305-1311, 2016

Authors: Zheng, Yisheng | Zhang, Xinong | Ma, Chicheng | Zhang, Zhifeng | Zhang, Shuai

Article Type: Research Article

Abstract: To design an ultra-low frequency (ULF) isolator, a magnetic spring composed of a pair of ring magnets is employed in parallel with the conventional pendulum. The magnetic spring can produce magnetic torque to cancel the gravitational torque of the pendulum and hence reduce the resonance frequency. The magnetic torque is calculated based on the Amperian current model. After establishing the analytical dynamic model of the ULF isolator, the transfer function is achieved and the isolation performance is evaluated from two aspects analytically: the resonance frequency and the center of percussion effect.

Keywords: Vibration isolation, ultra-low frequency, pendulum, magnetic spring

DOI: 10.3233/JAE-162161

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 52, no. 3-4, pp. 1313-1320, 2016

Authors: Dong, Guangxu | Zhang, Xinong | Luo, Yajun | Zhang, Yahong

Article Type: Research Article

Abstract: To improve the performance of vibration isolator in the low frequency region, a magnetic spring-beam vibration isolator with the high-static-low-dynamic stiffness (HSLDS) characteristic is developed in this paper. The proposed isolator is designed by combining a negative stiffness magnetic spring (NSMS) in parallel with an Euler-Bernoulli beam. The NSMS comprising four magnet pairs is utilized to reduce the resonant frequency of the isolator. An analytical expression of the negative stiffness (NS) of the NSMS is derived according to the Amperian current model, and the approximation to NS is deduced. Based on the harmonic balance method (HBM), the dynamic response of …the isolator is obtained and the impacts of external force and damping ratio on the force transmissibility are investigated numerically. The simulated results demonstrate that the NSMS can effectively reduce the resonant frequency of the isolator and broaden the bandwidth for vibration isolation. Also the damping property of the isolator with NSMS is improved. Show more

Keywords: Vibration isolation, negative stiffness magnetic spring, Euler-Bernoulli beam

DOI: 10.3233/JAE-162084

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 52, no. 3-4, pp. 1321-1329, 2016

Authors: Yang, Guicai | Pei, Cuixiang | Xiao, Pan | Chen, Zhenmao | Wang, Wanjin | Luo, Guangnan

Article Type: Research Article

Abstract: In this paper, an electromagnetic acoustic transducer (EMAT) method using rotating bias magnetic field was proposed for NDT of delamination defect in a thin multilayer tube of W-Cu monoblock in ITER divertor. To investigate its feasibility, a numerical simulation code was developed for EMAT signal simulation of tube configuration and uniform bias magnetic field. The EMAT signals of a typical EMAT transducer under bias magnetic field applied outside the tube were simulated for deboning defect of different size in the W-Cu interface of the mono-block. The reasonable sound speed and simple dependence of the signal amplitude on defect size demonstrated …that the developed code is efficient and the proposed rotating bias field EMAT is feasible for inspecting delamination defect in thin multilayer tubes. In addition, an experiment was carried out to investigate the influence of the rotating speed on the EMAT signals. It is found that a normal rotation speed does not give significant influence on the EMAT signals, which further support the validity of the rotating bias field EMAT. Show more

Keywords: EMAT, rotation bias magnetic field, monoblock, delamination, thin multilayer tube, Tokamak

DOI: 10.3233/JAE-162120

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 52, no. 3-4, pp. 1331-1339, 2016

Authors: Yamamoto, Tatsuya | Bu, Yinggang | Mizuno, Tsutomu

Article Type: Research Article

Abstract: Magnetic flux in the environment can be converted to electric power using a coil. However, to date, the power recovered has been miniscule because of increases in the AC resistance of the coil. This paper reports an investigation of the role of the core in the impedance of the coil, and the output power of the energy harvesting circuit of the leakage magnetic flux recovery coil. The use of a magnetoplated wire with a ferrite core in an energy harvesting circuit resulted in an increase in power of 29.3% to give 6.53 mW at 150 kHz in a uniform magnetic …flux density of 27 mT. Show more

Keywords: Energy harvesting, magnetoplated wire, ferrite core

DOI: 10.3233/JAE-162117

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 52, no. 3-4, pp. 1341-1349, 2016

Authors: Mao, Boyong | Xie, Shilin | Zhou, Jinxiong | Zhang, Xinong

Article Type: Research Article

Abstract: Dielectric electro-active polymer (DEAP) is a new kind of smart materials and has many advantages such as large deformation, fast response and so on. These features make dielectric elastomeric is a suitable material for actuators. In the article, a new type of DEAP vibration isolator is proposed, which utilizes the fiber stiffening DEAP membranes. The dynamic model of the DEAP isolator is developed by employing a nonequilibrium thermodynamic model. A set of harmonic vibration tests are conducted to identify the model parameters of DEAP isolator. The results show that the area of hysteresis loop increases with the increase of displacement …amplitude, and the dynamic stiffness of DEAP isolator increases with the increase of excitation frequency. An additional stiffness component is introduced thereafter in the model in order to correct the stiffness coefficients based on the measured data. Based on the identified isolator model, a simulated study on semi-active vibration isolation is also carried out. The simulated results show that the effective frequency range of vibration isolation can be expanded in some extent under DC input voltage. It indicates the feasibility of semi-active vibration isolation with the present DEAP isolator. Show more

Keywords: Dielectric elastomeric, DEAP isolator, fiber stiffening DEAP membrane, semi-active vibration isolation

DOI: 10.3233/JAE-162169

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 52, no. 3-4, pp. 1351-1358, 2016