International Journal of Applied Electromagnetics and Mechanics - Volume 45, issue 1-4

Authors: Kosaka, Daigo | Kojima, Fumio | Tanaka, Rika

Article Type: Research Article

Abstract: This paper discusses material aging diagnosis what uses a non-destructiveness evaluation system. The diagnosis is based on magnetic characteristics of material. It is well known that the magnetism of strong magnetic materials is extremely sensitive with respect to the change of microstructure and to residual-stress variation. For example, coercive force and minor-loop coefficients have shown a linear relationship with rolling reduction. We have proposed a method what is an impedance measurement of a …sensor. The method needs a magnetizer with one coil and an impedance meter. The method is simpler than a method what use coercive force. We have compared the method with a method what is a measurement of coercive force. Relationship between strain of carbon steels and experimental results of using coercive force or impedance measurements has measured. Carbon steel sample specimens with some strain loading in the experiment have been used. The experimental results have shown that the method can detect strain of steel just like a method of using a coercive force measurement. Show more

Keywords: Residual strain, ferromagnetic materials, magnetic properties, iron loss, impedance, eddy current testing

DOI: 10.3233/JAE-141925

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 45, no. 1-4, pp. 917-922, 2014

Authors: Nakamoto, Hiroyuki | Kojima, Fumio | Tabata, Hiroki | Kosaka, Daigo

Article Type: Research Article

Abstract: Non-destructive inspection is an important technique in the maintenance of plants and factories. It is necessary to appropriately evaluate the reliability of non-destructive inspection techniques. This study focuses on a reliability evaluation method for nondestructive inspections. The reliability method uses the probability of detection (POD) as a metric. A POD function is determined based on the thicknesses, signal responses, and a decision threshold for all pipe-wall measurements, and can be reasonably modeled by the cumulative …log normal distribution function. In this study, the POD is applied to reliability evaluations of an electromagnetic acoustic transducer (EMAT), which is a non-destructive inspection device. Using the results of experimental measurements, we confirm that the POD can evaluate the reliabilities of EMATs that have different specifications. Show more

Keywords: Reliability evaluation, electromagnetic acoustic transducer, probability of detection, pipe-wall thickness measurement

DOI: 10.3233/JAE-141926

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 45, no. 1-4, pp. 923-929, 2014

Authors: Kobayashi, Futoshi | Hasegawa, Ko | Nakamoto, Hiroyuki | Kojima, Fumio

Article Type: Research Article

Abstract: The multi-fingered robot hand has much attention in various fields. Many robot hands have been proposed so far and we have developed a hand/arm robot with universal robot hand II. The human type robot like the hand/arm robot can be operated by imitating the human motion. Various types of the human motion capture have been developed. However, it is difficult to capture the twist motion by the conventional motion capture. This paper deals with a motion …capture system with inertial measurement units (IMUs). The IMUs are used in order to estimate the joint angles of the operator's hand and arm. Show more

Keywords: Motion capture, inertial measurement unit, teleoperation

DOI: 10.3233/JAE-141927

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 45, no. 1-4, pp. 931-937, 2014

Authors: Wakabayashi, Daisuke | Enokizono, Masato

Article Type: Research Article

Abstract: In order to reduce acoustic noises and vibrations of electrical machines caused by magnetostriction, it is necessary to make clear the distribution of magnetostriction on magnetic core. The distribution of magnetostriction has been visualized by measured two-dimensional magnetostriction of electrical steel sheet and vector magnetic characteristics analysis technique. The distributions of vector magnetic characteristics and magnetostriction and the relationship between the magnetic flux density vector and two-dimensional magnetostriction have been made clear …in the method. Show more

Keywords: Two-dimensional magnetostriction, vector magnetic characteristic, electrical steel sheet, electrical machine, visualization

DOI: 10.3233/JAE-141928

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 45, no. 1-4, pp. 939-947, 2014

Authors: Han, Pil-Wan | Kim, Dong-Jun | Chun, Yon-Do | Choi, Jae-Hak | Seo, Un-Jae | Koo, Dae-Hyun

Article Type: Research Article

Abstract: High speed induction motors have the different design parameters and loss distribution compared with line start induction motor because of various load conditions and inverter-fed supply voltage. Especially harmonic losses and mechanical losses must be considered severely. In order to check the variation of the design parameters in inverter-fed induction motor, these values are compared with those of line start induction motor (sinusoidal supply voltage) at same rated output power. The experimental results are verified through …testing prototype of two types of 30 kW induction motor for loss analysis. The amount of harmonic loss is confirmed by calculating the loss differences between operating 4.5 kW induction motor from sinusoidal and inverter-fed supply voltage. Show more

Keywords: Induction motor, high speed, harmonic loss, mechanical loss, inverter-fed

DOI: 10.3233/JAE-141929

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 45, no. 1-4, pp. 949-955, 2014

Authors: Haq, Mahmoodul | Karpenko, Oleksii | Khomenko, Anton | Udpa, Lalita | Udpa, Satish

Article Type: Research Article

Abstract: Dissimilar material bonding has recently gained a lot of attention in automotive, marine and defense applications. Nevertheless, a major hurdle limiting the full acceptance of such structural components is the lack of non-destructive evaluation (NDE) technique to evaluate their strength, which depends on the integrity of the bonding layer. In this work, guided wave (GW) inspection with surface-mounted piezoelectric sensors (PZT) was employed along with time reversal for Structural Health Monitoring (SHM) of dissimilar …material lap-joints. Baseline-free probability imaging was used to identify the location of artificial disbond. The results of GW inspection were further validated with ultrasonic C-scan. Overall, the technique shows great potential in detection of defects in bonded joints. Show more

Keywords: Dissimilar material joints, SHM, guided waves, time reversal, diagnostic imaging

DOI: 10.3233/JAE-141930

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 45, no. 1-4, pp. 957-964, 2014

Authors: Xue, Xiaomin | Wu, Xiaohong | Chen, Luqi | Sun, Qing

Article Type: Research Article

Abstract: Hysteresis is an important nonlinear effect exhibited by the Macro Fiber Composite (MFC) that is testified from experimental study. In order to interpret the characteristic accurately, various models were proposed previously, in which the Bouc-Wen model has gained more interest because of its capability to match a wide class of hysteretic systems. However the model consists of a set of differential equations where multi parameters present need to be estimated simultaneously. In view of this, the …present study sets out to propose a more efficient Genetic Algorithm (GA) and a simplified Bouc-Wen model on the one hand, and on the other, the GA is applied to the model to enhance the accuracy and efficiency of the parameter estimation. Finally a large number of experimental data are used to testify the proposed approach more efficient and accurate than the other conventional methods. Also suggested are the implications of the present study on other hysteretic models or other complex mathematical models. Show more

Keywords: Macro fiber composite, actuator, Bouc-Wen model, sensitivity analysis, genetic algorithm

DOI: 10.3233/JAE-141931

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 45, no. 1-4, pp. 965-971, 2014

Authors: Chen, Luqi | Zhang, Ping | Wu, Xiaohong | Sun, Qing

Article Type: Research Article

Abstract: This paper presents a modified Preisach model to describe the nonlinear hysteresis property of Macro Fiber Composite (MFC). In order to apply the proposed model, two necessary and sufficient inherent properties which exist in most piezoelectric materials should be met, which are referred to as the wiped-out and the congruency. By using the hysteresis properties and the identified database, the numerical expressions of the proposed modified Preisach model are presented for different inputs in detail. Then …several waveforms of input excitation schemes are experimentally realized in order to demonstrate the effectiveness of the modified Preisach model. The good agreement between the measured and predicted results show that the modified Preisach model is an effective mean for predicting the hysteresis of the MFC actuator system. Show more

Keywords: Macro fiber composite (MFC), dynamics characteristics, electro-mechanical behavior, hysteresis property, modified Preisach model

DOI: 10.3233/JAE-141932

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 45, no. 1-4, pp. 973-979, 2014

Article Type: Other

Abstract: Author Index Volume 45 (2014)

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 45, no. 1-4, pp. 981-995, 2014