This paper deals with electronic sounds as one of the most common human-machine interface experimentally. The electronic sound is used as one of the very common means of human machine interface. Few investigations of how human feels to such the simple sounds noisy or comfortable, exist. The electronic sound must be designed by considering how or in what situation it is used. Our goal is developing a system evaluating electronic sounds to support designing electronic sound based on feeling evaluation.
6 words for evaluating electronic sounds are selected. To decrease the number of evaluation, the design of experiments is applied. Feeling evaluation experiments are carried out and the human auditory physiological feeling data about each 32 electronic sound are obtained. The experimental data obtained by evaluation tests were stored into artificial neural network. The network can automatically evaluate simple electronic sounds based on human feelings.

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To clarify the temporal limitation of the driver's steering behavior to avoid an obstacle ahead, avoidance maneuvers and results of avoidance operation were examined under the condition where the obstacle appearing timing was directly controlled on a driving simulator. All 25 subject drivers successfully avoided the obstacle when the time margin was longer than 3.0 seconds, though no drivers were able to avoid collision when the time margin was 1.2 seconds or shorter. When the driver was expecting an obstacle, it was confirmed that the steering latency decreased and the steering velocity increased as the time margin becomes shorter. The driver's minimum latency was estimated around 0.3 seconds and the maximum steering velocity around 500 degrees/second. However, the performance to avoid an obstacle deteriorated and the ratio of successful avoidance decreased when the driver was not anticipating appearance of an obstacle.

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This study investigated the influence of whole body vibration applied with low level of acceleration on humans during sleep onset. The characteristic vibration of electric trains was utilized along with 1/f fluctuation pattern. Sixteen healthy participants were exposed to three patterns of motion for 10 minutes using a reclining chair with the vibration capability. Pattern 1 consisted of continuous vertical vibration superimposed with intermittent horizontal vibration. Pattern 2 consisted of continuous horizontal vibration superimposed with intermittent vertical vibration. Pattern 3 which served as a reference for comparison was no vibration. Results obtained with patterns 1 and 2 can be summarized as follows: The sleep latency was shortened and the sleep amount defined as summation of the product of sleep stage and appearance time was increased. % change from baseline in R-R interval and the ECG CV_R-R increased. Results suggest that whole body vibration with low level of acceleration induced the function of the parasympathetic nervous system leading to sleep.

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We made four basic skirt patterns and discussed their relationship between physical-type characteristics of the lower half of the body of young adult women and patterns and measurement items. The subjects consisted of 346 young adult women ranging in age from 20 to 21. The four basic skirts were found to be well-fitting for 307 of the young women. To improve fitting for basic skirts, it was necessary to measure the waist and hip girth, front and back, side length waist to hips, remainder of front and back waist height items, front waist girth items. Based on body size and figure, clothing that is not only comfortable but well-fitting could be made.

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Human personal distance against a mobile robot was studied experimentally by subjective report and heart rate measurement. Subjects were 17 men and women, aged 53-83 years. The robot moved toward standing or sitting subjects at constant velocities from 0.2 to 1.0m/s from a distance 10m apart. Personal distance was reported by subjects at the moment when they first felt uncomfortable. The distance at that time between subjects' tiptoe and the robot, was referred to personal distance. There were no sex difference in personal distance. Personal distance was extended in proportion of the speed of moving robot. Personal distance of old subjects were longer than young. Results show, we could considered that human personal distance against mobile robot was 3.3m from human, in case of at the fastest speed, 1.0m/s.

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This paper described the process involved in constructing a stress scale, designed to focus on phasic task demands. The scale was coined “Phasic Stress Scale” (PSS). PSS was aimed to be used by manufactures in assessing the stress level of users of various products in various environments. PSS was uniquely constructed based on the structure of the stress-related change of feelings, as feelings are the core of all stress responses. Two surveys were conducted to investigate the structure of how feelings change and to thereby select relevant words to these feelings. Its reliability and validity were also discussed. PSS consisted of four dimensional scales which represent feelings of 1) comfort, 2) anger, 3) languor/boredom, and 4) anxiety/uneasiness. The relevant words used to evaluate the respective scales were 1) relieved, pleasant, comfort, refreshed, 2) provoked, anger, offended, irritated, 3) tired, ineffective, gloomy, and 4) timid, confused, worried, depressed. Finally, the practical usage of PSS was discussed.

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As a supplement to the previous report (Kurakata et al., The Japanese Journal of Ergonomics, Vol. 34, No. 4, 1998), the audio signals used in electric home appliances were investigated to identify suitable signals for the hearing ability of older adults. First, the audio signals in appliances made by eight manufacturers in Japan were recorded. Then their frequencies and sound pressure levels were analyzed. Next, based on the hearing levels of young adults and the elderly, thresholds of hearing were estimated as a function of frequency to show frequency-intensity regions audible for different age groups. The results of the measurements confirmed the conclusion of the previous report that many of the audio signals could not be heard by the elderly and lower-frequency tones should be used as signals. These results might well serve as basic data to design audio signals suitable for both young adults and senior citizens.

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