Since odor sensing system is required in many fields, we have developed the system using QCM (Quartz Crystal Microbalance) array and neural-network pattern recognition. Moreover, the system for measuring many samples by an automatic sampling stage has been developed. In the present study, the characterization of the sensing films deposited on QCMs was performed. Responses of 37 kinds of films exposed to 14 sorts of organic vapors were studied to classify sensing films and investigate sensor response models. As a result of the research, it was found that the similarities among films were obtained using principal component analysis, and the frequency shifts could be estimated using multiple regression analysis.

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In a previous paper we reported on a new type of electrostatically-driven gas valve enabling high conductance, and showed that is applicable in rarefied gas conditions in semiconductor manufacturing equipment. In this paper, we determine that this gas valve can operate properly at high pressure several times higher than atmospheric pressure. For proper operation of the valve, the electrostatic force must be greater than the gas pressure. We experimentally examine the ultimate pressure difference of the valve operation, which depends on the applied voltage and the port size. The valve works in higher pressure differences when the port aperture size is smaller or the applied voltage is larger. A gas valve having a port aperture size of 45×45μm successfully operates in an air pressure of 0.8MPa at the applied voltage of 80V.

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A miniature torque sensor based on magnetostrictive effect, has been developed to be mounted inside an automobile engine (TOYOTA 4A-FE; 1.6-liter 4-cylinder). The sensor was installed in a last main bearing of the engine crankshaft so as to directly detect the torque generated by engine. This sensor was composed of two magnetic head-type elements, which were placed opposite to each other through the crankshaft in order to eliminate the influence of the off-center motion of the shaft on the sensor output. Furthermore, a commercial crankshaft made of cast nodular iron (JIS standard: FCD70) was adopted, taking account of high sensor sensitivity and mechanical stiffness.
It was confirmed by tests on an engine-dynamometer arrangement that this sensor could clearly detect instantaneous torque waveform with four peaks during two crankshaft rotations, corresponding to four cylinder combustions, and peculiar torque fluctuation due to engine lean burn. In addition, it was found that true torque produced by engine could be detected in in-vehicle experiment. This sensor is useful for various automobile applications.

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This paper describes a new compensation method for the temperature offset drift on the semiconductor piezoresistive sensors such as pressure sensor and accelerometer.
The offset drift compensation was conventionally carried out with the method in which a parallel resistor is inserted into a part of the piezoresistive gages. This method, however, has a disadvantage in that the second-order errors dependent both on the second-order coefficient of piezoresistors and that of the original offset drift remain.
We used a new temperature compensation circuit including a temperature sensitive voltage supply and a compensation resistor, with which both the first-order and the second-order temperature offset drift could be completely canceled, achieving about 1/30 reduction of the offset temperature error, compared with the conventional method.

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