Electrical interference with pickup coil in induction magnetometer

2011 Fifth International Conference on Sensing Technology took place 28 November - 1 December 2011 in Palmerston North, New ZealandIn this paper, we consider electrical interference with pickup coil in an induction magnetometer. By using a dummy load in place the pickup coil, we confirm that there is no significant electrical interference with a differential-input type current-to-voltage converter. In order to reveal electrical interference with the pickup coil, we investigate the output voltage of the magnetometer as grounding condition parameters. From the number of experimental considerations, we formulate a suitable condition to solve the electrical interference problemArticleSensing Technology (ICST), 2011 Fifth International Conference on : 90-93 (2011)conference pape

Residual magnetization measurements of a motor to be used in satellites

Thursday 3 December 2009, Gwangju, Korea, Republic of ICMIT 2009: Mechatronics and Information TechnologyA simple magnetic shielding system for residual magnetization measurements of a motor to be used in satellites is studied. The system consists of same-sized square coils, namely three sets of Simple Cubic-3 coil system. Because the system can generate a uniform magnetic field, we investigate the uniformity of the site. With a first-order gradient coil, the geomagnetic field can be reduced to less than 100 nT in a relatively large area. Inside of the system, the residual magnetization measurements of a step motor are demonstrated. An approach to reduce the magnetic field leakage from the step motor is also presented.ArticleA. Matsuoka, K. Matsumura, A. Kubota, K. Tashiro and H. Wakiwaka, "Residual magnetization measurements of a motor to be used in satellites", Proc. SPIE 7500, 750012 (2009).journal articl

Energy Harvesting of Magnetic Power-Line Noise

The purpose of this study is to demonstrate the energy harvesting of power-line magnetic noise. To the best of the authors' knowledge, no research has yet been carried out to confirm this possibility. In this paper, we present a simple circuit design model, and confirm its validity by experimental results. For small self-sufficient devices in a wireless sensor network, the target energy level is 1 mW. We prepare an energy harvesting module with an air-core coil and resonant capacitor. From experimental and simulated results, we investigate the desired conditions for harvesting 1 mW from a uniform magnetic field of 60 Hz. Through experimental results with iron cores, the benefits and drawbacks of the use of a magnetic core are also discussed. With our best harvested module, we successfully demonstrated the energy harvesting of 6.32 mW from a magnetic field of 21.2 μT at 60 Hz. If the usable magnetic flux density increases tenfold, the harvesting energy increased 100-fold. If the magnetic flux density is at an acceptable level in a public space of 200 μT at 60 Hz, the harvesting power density becomes 130 μW/cm3. This value is comparable to the value of an energy harvesting module of a light source during a cloudy day.ArticleIEEE TRANSACTIONS ON MAGNETICS. 47(10):4441-4444 (2011)journal articl

Application of ECT Technique for Inspection of Bare PCB

The detection of imperfections (such as disconnections, chipping cracks, nonuniformity in thickness and short-circuit, etc.) on the traces of bare printed circuit board (PCB) using a new high-sensitive eddy-current testing (ECT) probe has been reported in this paper. The ECT technique is composed of planar meander type exciting coil and a new multiple solenoid sensing coil. The image processing method is used to analyze the results. This paper has discussed the structure of the new probe, the characteristics of the measurement technique to inspect high-density PCB with narrow conductor-width. And the possibility of detecting micro-metal ball has been explored.A new application of eddy current testing techniques for investigating trace defects on printed circuit boards is proposed, A test probe consisting of a meander type exciting coil is used to induce eddy currents. The following three experiments are conducted: measuring the induced signal when a circuit trace is cut; measuring the induced signal for a number of traces placed in parallel and with a cut in the centre trace; measuring the induced signal for two back to back right angle traces. The experimental results reveal that it is possible to clearly detect defects and that the signal response obtained is strongly associated with a particular defect pattern. The signals obtained from a high density patterned board have a complicated signal signature and are therefore difficult to interpret. This complexity can be avoided by comparing the signal signature of a known good board with a defective board. The difference signal gives a clear indication of a trace defect

Application of Eddy-current testing technique for high-density double-layer printed circuit board inspection

金沢大学環日本海域環境研究センター生体機能計測研究部

Performance Analysis of 6 Slot 8 Pole Permanent Magnet Linear Motor

Currently, palm oil is the mostconsumedvegetable oilin the world. Therefore, an increment in its productivity is essential to ensure its sustainability in the market. One option is through the mechanization of the tools used to harvest it. In this paper, the design of the actuator for mechanized oil palm harvesting tools was discussed. A 3 phase permanent magnet linear motor with a 6 slot 8 pole structure topology known as 3PhSTLOA was used as the actuator structure. The structure of 3PhSTLOA has been optimized. The aim of the optimization is to allow the 3PhSTLOA to produce at least 200 N of average thrust at a total weight of under 2.0 kg. As a result of optimizing the 3PhSTLOA produced about 202 N of average thrust at 1.8 kg of its total weight. The performance of 3PhSTLOA is then compared with the previous type of actuator in mechanized harvesting tools

Application of Eddy-Current Testing Technique for High-Density Double-Layer Printed circuit Board Inspection

High-density double-layer printed circuit board (PCB) inspection based on the eddy-current testing (ECT) technique is proposed in this paper. The ECT probe, which consisted of a planar meander exciting coil and spin-valve giant magnetoresistance (SV-GMR) sensor array, is used for this propose. Defects on both the top- and bottom-layer of the high-density double-layer PCB are examined by the ECT technique with scanning over either the top or bottom layer. The characteristics of the proposed ECT probe for high-density double-layer PCB inspection are studied. The inspection results of the high-density double-layer PCB model verify that applying the ECT technique enables identification of the defects of both the top and bottom layer with one-side scanning