近年、パソコン作業や監視業務などVDT(Visual Display Terminal)作業が増加している．VDT作業は座位での作業を長時間強いられるため，腰部への負担を増加させ，腰痛発生の原因となる．本研究は，アクチュエータを持ち能動的に座面を傾動させることのできる椅子によって姿勢の固着を防止し，腰痛発生の予防を目指している．被験者実験を行い，被験者の筋疲労と精神的疲労を評価する．

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二足歩行ロボットの新たな歩行動作の開発をしている．人間の援助を目的に作られた二足歩行ロボットだが，従来の歩行能力で階段などの段差に完全に対応できるものはほとんどない．そこで，腰に原点をおき微小角度だけ上半身を傾け，そのときの重心位置を計算し，目標とする重心位置と最も近い体の傾きを順次選択する重心移動を行う．階段や凹凸のある路面で姿勢を逐次修正し対応することで，歩行動作を創成することが目的である．

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In the search for a stable and reliable thin sheet induction, there is an interest to control the optimal frequency by design of stator and slider. This paper investigates properties that affect the optimal frequency in driving surface-drive film actuators. Four different six-phase electrostatic actuators were designed, with 7.2 mm, 4.8 mm and 3.6 mm pitch respectively, to generate different wavelengths of traveling waves while keeping the same 0.04 mm electrode height. With a 1kVp-p applied excitation voltage, force and velocity performance of the slider was measured with a frequency range from 2 Hz to 1000 Hz. The experiments were conducted with regular plain paper copy paper as sliders, with a surface resistance between 1012 - 1013 Ω. The experimental results showed that the actuator with 3.6 mm wavelength has the highest optimal frequency between the three actuators and gave a better performance in both thrust force and velocity. The results also shows that the slider with 1012 Ω has its optimal frequency in higher frequency band. The information obtained from this study will prove useful as a basis for future design of this induction type electrostatic actuator.

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This paper presents the design, fabrication, and experimental performance verification of a bidirectional rotary actuator using shape memory alloy (SMA) wires. To achieve more multifunctional and wider applicability in comparison with previously reported various types of SMA rotary actuator, a rotational driving mechanism based on wobble motor driving principle is devised and applied to the proposed rotary actuator. The rotational driving mechanism consists of a rotationally fixed rotor gear, a wobbling annular gear eccentrically engaged with the rotor gear, and three equal crankshafts. The wobbling motion of the annular gear is generated by sequentially activated three SMA wires, and this motion is guided as curvilinear translation due to triple parallel-crank-mechanism formed by the three crankshafts. Each SMA wire connected in series with a bias spring is electrically heated up, and it is cooled down by natural convection. In this research, a functional prototype is fabricated for experimental performance verification. For high gear efficiency, quiet and smooth operating, a cycloidal gear set is utilized for the actuator. With diverse activation sequencing methods, performance characterizations are conducted. The proposed SMA rotary actuator, based on its structural modularity and operational simplicity, is expected to be applied to diverse scientific and industrial fields.

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Today, there is an increased need for quality control in the manufacturing sectors. Particularly, the automated detection of the product surface defect is essential to fulfill the requirement of quality assurance. In this research, the algorithm of surface defect detection by use of wavelet transform has been developed. This method is established by one-dimensional wavelet filter. However, the image processing of 2D image for defect detection should be applied by two-dimensional filter. Therefore, in this report, a new wavelet transform is developed with 2D filter and the method is called for areal wavelet transform. This areal wavelet transform is investigated and is confirmed the efficacy.

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This work proposes a methodology to monitor the wear of tribological coatings by introducing a sensing layer between the coatings and substrate. The sensing mechanism is based on luminescence from the sensing layer when the coatings are worn out. In this work, the wear sensing layer consisting of as-purchased luminescence ZnS:Cu powder with particle size of 10-20 micrometers and epoxy resin (EP/ZnS:Cu) is initially fabricated. The as-prepared EP/ZnS:Cu coatings are subsequently coated with amorphous carbon (a-C) films by two deposition methods, i.e. sublimation of fullerene (C60) in electron beam excited plasma (EBEP) and pulsed vacuum arc deposition (VAD) methods. As-prepared EP/ZnS:Cu coatings show a green luminescence spectrum at the peak centre of 525 nm under irradiating with a UV light at 365 nm. After being coated with a-C films and irradiated with a UV light, the luminescence is undetected through a-C films. The performance of the coatings is investigated by a ball-on-disk friction test. It is found that after the a-C film is removed or worn out, the luminescence from the sensing layer is redetected. These results suggest the feasibility of wear monitoring of a-C film through the luminescent layer.

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