The constrained posture used for work with a visual display terminal (VDT), such as data entry, can produce static muscular fatigue. We conducted an experiment using a prototype VDT chair designed with an arm-rest adjustable to heights from 22-28cm. The experiment—conducted to assess the work load based on varying heights of the armrest and distance from the keyboard—was performed on five male subjects. The keyboard was placed at 0cm or 8cm from the frontal edge of the desk. The subjects were required to type characters displayed in random sequences on CRT with both hands.
Results revealed that EMG activities and error rate decreased with the arm-rests height adjusted according to the subjects'. But some experimental conditions, using the arm-rests increased the EMG activities compared with the without arm-rest condition. The result suggests that VDT chair with adjustable arm-rests is effective in reducing the muscular fatigue.

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This research is to examine the differences between simulated flight, in which no physical factors of accerelation and atmospheric pressure but mental factors are predominant, and actual flight combined with mental and physical factors, from an index of pilot's heart rate. Furthermore, statistical measure was examined to presume pilot's heart rates of actual flight from the ones obtained in the simulated flight.
The flight phase when a pilot gets tense best is recognized as takeoff and landing in which peak tension occurs at airborn and at before-touchdown respectively. Therefore, a statistical heart rate measure to identify peculiar psychophysical responses in the specified flight phase such as takeoff and landing was analyzed for comparing the simulated flight with the actual flight. Maximum average heart rate was a good measure to show the peculiar psychophysical response in the specified flight phase under the simulated flight condition. The maximum average heart rate of “takeoff” was the highest among all flight tasks, and the next was landing, and the third was MTT, minimum timed turn flight, which has a larger accerelation loading. The influence of predominant mental type of flight tasks on increment of heart rate was stronger than flight tasks which has a larger accerelation loading. The mean heart rate or the maximum average heart rate under the simulated flight conditions were lower than the mean heart rates in the actual flights. “Maximum average heart rate +1.0σ” was in good condition as a predictive measure of mean heart rate in actual flight condition.

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The passage which wheelchair user are easy to use is examined. Subjects are 7 spinal cord injuries and 6 are quadriplegia. Subjects run 5m passages which established in a laboratory with own wheelchair. The situation of this time is recorded with video camera fixed 8m high. The time for passing the straight passage, the bent passage, passage with cross paths and turning of wheelchair are measured. Width and length of wheelchair are set up as in a standard. As in the results, the straight passage width of more than the wheelchair width +300mm are easy to use for the wheelchair user. In the bent passage, width more than the wheelchair width +400mm are easy to use. At cross paths with wheelchair, passage width of over 350mm add two wheelchairs width is easy to use. In a 90° turn of wheelchair, it is the square size that is easy to turn, if 1 side length of a square is over 300mm add a wheelchair length. In 180° turn, it is more than 400mm add a wheelchair length.

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This study examines the effects of visual and tactile feedback on fine positioning tasks. Two experiments were performed in which a caliper's slider is positioned using a thumb. In Experiment 1, the comparison between analog and digital displays of the slider's position was made to investigate the influence of the visual feedback. The movement time in the task using the analog display is smaller than that of digital. In Experiment 2, positioning resolution is varied from 1.0 to 0.01mm to get the influence of the tactile feedback. In case of high resolution, the movement time becomes large and the variance among subjects also becomes large. According to the analysis with slider's time-movement curves, which are divided into course and fine positioning phases, the visual feedback is effective at the fine positioning phase and the tactile feedback is effective both for an early stage of the course positioning and for the fine positioning. Especially, the ability for smooth coordination between the tactile feedback and the thumb movement at the fine positioning phase is found to be essential, and to be evaluated by the movement-time's dissociation from the Fitts' Law.

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A data analysis using Tucker model is proposed to analyze the individual differences of Kansei applying to the evaluation of styling of steering wheels by Semantic Differential (SD) method. The individual differences mean the differences of image space and factor scores of objects, however, in this paper the difference of image space is emphasized. The proposed procedure consists of two parts as follows: Firstly the individual differences are identified from the data of image adjective pairs excluding adjective pairs which are directly related with preference. Secondary, the relationships between preference and the image space are analyzed. The fundamental theory from the analysis of the individual differences is the differences of the inter-factor correlation which can be derived from using Tucker model. The proposed procedure are applied to the evaluation of the styling of steering wheels. As the results of the application, three different image spaces can be identified, and the relationships between preference and these image spaces can be analyzed.

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