Hiroyuki Wakiwaka

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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(More)
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(More)
Linear motor has gain popularity as linear motion drive in office and factory automation which provides an alternative method to conventional rotary motor. Chip mounting is one of linear motor applications especially for linear DC motor (LDM). Displacement sensor which is normally used for positioning on the system, made the system expensive. This paper(More)
Hisashi YAJIMA, Hiroyuki WAKIWAKA, Shin-ichi SENHO Faculty of Engineering, Shinshu Univ., 500 Wakasato, Nagano 380, JAPAN Keiichi MINEGISHI, Nobuhiro FUJIWARA, Kazuya TAMURA SMC Corporation, 42-2 Kimunodai, Yawara-mura, Tsukuba-gun 300-24, JAPAN Introduction A linear motor has big advantages of moving in the direct straight line. A linear DC motor (LDM),(More)
Stable operating conditions for a high-sensitivity induction gradiometer are studied experimentally. In order to reduce electrical interferences in our developed induction gradiometer, we construct a Faraday cage. It consists of copper mesh and wood, and is 2.0 mtimes1.8 mtimes1.8 m in size. Experimental results show that the inside of the cage can provide(More)
This paper proposes an eddy-current testing (ECT) probe composed of a spin-valve giant magnetoresistance (SV-GMR) sensor and a meander coil for the inspection of bare printed circuit board. The SV-GMR sensor serves as a magnetic sensor for the ECT probe to sense the variation of the magnetic field distribution occurred on the printed circuit board. The(More)
Linear motor has been applied in various fields such as factory and office automation. A linear motor differs from a rotational motor, in which it has a simpler structure. Linear Synchronous Motor is one of the types of linear motor and its application is very wide which is from the small application (i.e. industrials automation) to large application (i.e.(More)
This paper discusses the effect of inductive coil shape on the sensing performance of a linear displacement sensor. The linear displacement sensor consists of a thin type inductive coil with a thin pattern guide, thus being suitable for tiny space applications. The position can be detected by measuring the inductance of the inductive coil. At each position(More)
Among palm oil millers, the ripeness of oil palm Fresh Fruit Bunch (FFB) is determined through visual inspection. To increase the productivity of the millers, many researchers have proposed with a new detection method to replace the conventional one. The sensitivity of such a sensor plays a crucial role in determining the effectiveness of the method. In our(More)
This paper presents the design of liquid detection sensor with low-frequency electromagnetic field. The purpose of this sensor is to detect a change in the conductivity or permittivity of the liquid. If the evaluation frequency is less than 100 kHz, skin effects would be negligible. This paper proposes sensor that consists of two cylindrical sensors, a(More)