In this paper, we propose a new algorithm of an automotive direction finding method by using the fluxgate magnetometer. Conventionally known an automotive direction finding methods make use of two pickup sensors, x and y, are arranged to make their reference lines perpendicular to each other. All sensor data are converted into DC voltage V_x and V_y respectively which are proportional to each component of the geomagnetic field which is parallel to each reference line. The direction of the geomagnetic field with respect to the reference line of the sensor x is θ=tan^-1 (V_y/V_x). However, because of the disparity of the mutual sensitivity of these two sensors, there is a limit in the improvement of the sensitivity of the automotive direction finding system.
In this new algorithm, an automotive direction angle θ can be determined with at least one sensor for measuring the horizontal component of the geomagnetic field with good accuracy. In some conditions, it is demonstrated that the equation which is derived from the new algorithm is equal to the conventional automotive direction finding equation.

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There is a demand to know occlusal wear. To meet this demand, we have developed a sensor system and successfully detected the tooth occlusal force and relative position between upper and lower tooth. The force sensor was fabricated by using silicon micromachining. The position sensor consists of a micro-inductor and three individual coils, and magnetic coupling effect between them was utilized to determine the relative positions of the facing upper and lower teeth. These sensors were built in the artificial teeth.

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A fabrication process of tungsten probes for surface profile measurements has been improved. The probe contour is designed to have an optimum shape for the use of tapping stylus. An improved DC electropolishing is applied for the elimination of surface impurities and smaller stylus radius with exponential contour, which uses an electrical flushing and a surface tension control of the electrolyte. The process is experimentally confirmed to have advantages for the fabrication of the stabilized stylus contour, typically with a stylus radius of 30nm. They have smoother contours compared with those fabricated by AC electropolishing.

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This paper presents a novel environment perception approach based on multi-layer sensing technique using one multifunctional sensor to measure temperature, humidity and brightness. It focuses on the processing of the multi-functional information in a multi-layer framework, which is more attractive in terms of both system simplicity and performance, and is proved to be effective to solve the problem of more than three quantities being reconstructed. A CdS and Fe₃O₄ material based multi-function sensor has been developed and the multi-layer data fusion idea has also been proposed for the use.

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The electro optic (EO) sampling method is a technology to allow the measurement of high-speed electric signals with "non-contact" and "low disturbance." To achieve excellent reproducibility measurement, control of the vertical EO probe position needs to have sub-micron accuracy. Therefore to realize this, we had to design a probe with a characteristic frequency of several kilohertz and a mechanism that can prevent the probe position from being affected from external vibration. We have developed an EO probe that employs a micro-balance mechanism and has been manufactured using quartz micro machining technology. This probe realized a high characteristic frequency and applies an extremely small contact load to the measured ICs.

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For the design of thermal sensor, heat transfer in a micro-bridge heater should be revealed. The power input is measured as a function of temperature rise both in air and in vacuum to separate the heat transfer through air. The ratio of the transfer through air to the other transfer is investigated as a function of the heating area. The result indicates that the transfer through air is proportional to the area, and the transfer though air on the beams is separated.

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This paper describes a newly developed, normally closed microvalve composed of a molded polydimethylsiloxane (PDMS) microchannel (width 140μm × height 25μm) and a spin-coated PDMS membrane (350μm square), which is deflected by external negative air pressure. By adopting replica molding technique and deep reactive ion etching (DRIE), the fabrication process has been largely simplified in comparison with previously reported microvalves. Load-deflection data of the membrane and flow characteristics of the microvalve are presented. The microvalve works in an on-off style with hysteresis. No leakage has been observed in the closed state.

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