Various kind of driving units are frequently used in office machines, which sometimes require the reduction in size and capability of accurate positioning. A self-running linear actuator using piezoelectric resonators have been proposed. To design the desirable actuator size for this purpose, dimensional contributions of the elements are studied by solving resonant frequency and displacement amplitude by the finite element modeling, in which the effect of the loading is ignored. The relationship between the size and resonant frequency or amplitude displacement together with the prototype's experiments are derived. It is proved that much smaller actuators could be developed the driving units in office machines.

抄録全体を表示

Magnetic configuration of a current sensor using an inductive magnetic detector is described. The inductive magnetic detectors have been developed as a detector for a weak magnetic field, whereas it needs something new ideas to detect a strong magnetic field like a field caused by a large current. In this paper, to realize a current sensor for a large current, suitable structures of a magnetic core for a detector and a magnetic yoke surrounding a current wire are investigated. A magnetic field simulator is utilized to confirm the strength of magnetic fields under analysis. As a result current amplitude ±500A is successfully detected within linearity errors of ±0.2%.

抄録全体を表示

Barium Strontium Titanate (Ba_1-xSr_xTiO₃) ferroelectric thin films have been prepared by Metal Organic Decomposition (MOD) on Pt/Ti/SiO₂/Si and on micromachined Pt/Ti/NSG/Si₃N₄/SiO₂/Si wafer with an aim to fabricate dielectric bolometer type infrared sensor. The XRD pattern and D-V hysteresis curve of the film have been measured in order to investigate the effects of the final annealing temperature and annealing time on the property of the film. The results show that the films annealed at 700 or 800°C all have good perovskite structure, while the film annealed at 800°C has better ferroelectric loops. Films annealed at 800°C with different annealing time from 5 to 60 minutes show a similar perovskite structure, among which films annealed at 30 and 60 minutes condition have the better ferroelectric loops. Temperature Coefficient of Dielectric constant (TCD) of the MOD made BST thin film on micromachined substrate is about 1%/K. The uniformity of the BST film on micromachined Si wafer also has been confirmed to be well enough for operation of sensor array.

抄録全体を表示

Human can localize a sound source even when it is on the median plane. The sense of elevation like this is called as monaural sound source localization. The cues are said to be generated by the reflection on the pinna as the elevation-dependent dips (zeros) of the spectral distribution. In human auditory system, they are detected by cochlea. In this paper, by using Fishbone sensor for direct frequency decomposition of the incident sound, we realize this principle as a novel sensor system which consists of 1) a logarithmic spiral reflector mimicking the human pinna, and 2) a Fishbone sensor mimicking human cochlea. We describe a theory for an optimal shape of a reflector (pinna). We show a design and fabrication of the overall system and experimental results using it.

抄録全体を表示

This paper describes a novel simple process suitable for fabrication of grating coupler on the optical waveguide using silicon mold. The mold was fabricated using electron beam lithography and fast atom beam etching. Submicron grating patterns were transferred from silicon mold to polymer waveguide layer. In the transfer, grating coupler and waveguide was fabricated simultaneously by the mold at room temperature in the air. In the proposed method, the good replication in submicron region is realized by the casting method without pressing. Maximum coupling efficiency 25% was obtained. This technique can also be used to fabricate other nanometer-scale structures.

抄録全体を表示

This paper presents the structure and fabrication process of a thermoelectric infrared sensor that provides high responsivity and a low cost potential. The processes for obtaining a precisely patterned Au-black infrared absorbing layer and reducing the internal stress of the Si₃N₄ layer deposited by LP-CVD achieve both high responsivity and an excellent time constant. A prototype sensor, having external dimensions of 160μm×160μm and six pairs of thermopiles, achieved responsivity of 2100V/W and a time constant of 25msec at a pressure of 7.33Pa. This Performance is suitable for automotive applications.

抄録全体を表示

Environmental sensor which can detect and identify environmental pollution in real time is needed. It could be made by using Multiple internal reflection FTIR(MIR-FTIR) because of its short measurement time and high sensitivity. We chose GaAs which transmits large band lights which many molecule vibration exist in. It is possible to identify the gas which exists in the atmosphere around the crystal by FTIR spectrums. It is also possible to measure concentration of the gas in the atmosphere by measuring peak intensity of it. The result of reproducibility experiment will be reported finally.

抄録全体を表示

MEMS (Micro-ElectroMechanical Systems) are key technologies for manufacturing in many industrial regions. Today's rapid growth and commercialization of MEMS requires equally rapid product development. Virtual manufacturing, which is usually referred to as computer aided engineering (CAE), enables this rapid product development especially in MEMS world, because computer simulations can address the effect of miniaturization. In this paper, the process of virtual manufacturing on the computer is described step by step through a micro-mirror device, and the numerical result by a CAE tool is compared to the experimental ones obtained from real manufacturing.

抄録全体を表示

Recognition rate of human behaviors in a residence is improved using an association rule, which is widely used in the field of the data mining. In the present study, plural odor-sensor characteristics are adopted to introduce the features of the behaviors. The rules in the database with positive instances, which are the real data, can be derived in this method. On the other hand, the negative instances are also focused to introduce various kinds of behavior-features. These instances express error data in the recognition process. First, we propose a method by which the positive and negative rules can be derived from the both kinds of instances. And we supose that the recognition results can be obtained by the rules. Secondarily, we perform evaluation experiments and compare the recognition rates of the LBG clustering with those of the proposed method. As for the results, we achieved the following results. (1) The recognition rate can be improved by the proposed method except the case of lack of the negative instances and the case of category in which the same activities are included as the positive and negative instances. (2) By analyzing the activity history, which the resident recorded his behaviors, we confirmed that the positive and the negative rules could correct the recognition results. The proposed method is useful to recognize the human behaviors in the residence.

抄録全体を表示