This study deals with the effect of attention awakened by an auditory stimulus on human learning characteristics in a manual control system, as a basic study for constructing a training system which utilizes human cognitive characteristics. Based on knowledge that the focal attention increases both the sensitivity of perception and the processing speed, the training, which awakens a trainee to attention for the occurrence of some specific reference signal, is tried. The reference signal was made by repeating the identical random signal five times. The auditory stimulus was presented to the trainee immediately before the third signal occurred. Such training was repeatedly imposed on the trainee. It was confirmed that the auditory stimulus was effective for the improvement on the control performance not only for the signal in which the auditory stimulus was presented but also for other signals. However, the improvement speed of the performance differed on each signal. It was concluded that these differences might be caused by the type of attention (passive and active attention) and that the existence of these types of attention contributed to the effective control improvement.

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The purpose of this study is to investigate the safety and comfort of a speed-variable moving lane newly developed. The velocity influenced to user's feeling and performance. From the result of experiment, an appropriate speeds is considered to be about 2.1 kilometers per hour at an entrance of the lane and about 3.8 kilometers per hour in the middle part with higher speed. Also, for some users whose posture control was unstable due to wheelchair, baby carriage and highheeled shoes, the appropriate speed appeared to be less. The ways to avoid contacts and collisions among users at an exit were evaluated in several experiments. Several suggestions are described to feel comfortable when using a speed-variable moving lane.

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This paper describes path planning with respect to the thumb and index finger when the human extends the arm to the target object and grasps it. As the hand approaches the object, the span between the tips of the thumb and index finger is widened to be just larger than the width of the object. Even though the initial position of the hand is located at the right or left side of the frontal one, the motion of widening the span isn't performed excessively, but the velocity peak of widening appears slower than the case of the frontal grasping motion. The path planning of the two tips correlates closely with that of the wrist, and depends on the width of the object. When the object width is small, the shortest route is selected. In the case of the large width object, two tips trace a circular arc and approach from the front side of the object. The motion of reducing the span is performed just when the wrist velocity converges, regardless of the initial position. Moreover, the path model is suggested, and it is confirmed that the comparison between the model parameters of the two tips and wrist can judge the resemblance of the path.

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A compact relaxation chair for personal use is proposed based on the concept of rigid support, which allows removal of cushion volume and simplification of the overall structure. The most comfortable supporting line was determined for sixty-three subjects (Average: 29.3 years old, 169.4cm, and 62.8kg) using an experimental chair. The surface of the experimental chair is divided laterally into 16 narrow rigid plates. The supporting height and cushion spring of each plate are freely adjustable. The back and seat angles of the experimental chair were fixed as 30 and 15 degrees, respectively. Pillow position and angle of ottoman were individually adjusted. The range of comfortable seat lines, as determined by the adjustment of the supporting height, was small; therefore, the average line was accepted as the common comfortable seat line. Determined backrest lines were classified into the following four types: flat upper-back/convex lower-back, concave upper-back/flat lower-back, flat upper-back/flat lower-back, and concave upper-back/convex lower-back. Sensory evaluation performed by sitting against each of the four backrest types revealed the concave upper-back (maximum depth: 6mm)/convex lower-back (maximum height: 8mm) to be the most comfortable supporting line, regardless of individual physique.

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The word of comfort is popularly used but there is still no clear definition about it from engineering side and it has not yet become the concept, which can be available for the product design. The main purpose of this study, therefore, is to develop a method, which can be, evaluated the comfort of product structurally and applied it to product design through the investigation of the characteristics of comfort. Firstly, the characteristics of comfort (the comfort shaping factors; called as CSFs) which can influence on comfort of working based on the viewpoint of ergonomics in the past studies. Then, the relation of CSFs and the interface characteristics of various products was analyzed through the questionnaire surveys and categorized their features. Secondarily, method of evaluating about the variations of comfortability that was accompanied with the change of each specification interface; (1) The selection of the product and the CSFs in it's use. (2) The calculation of the influence coefficient for exertion forward each CSFs (3) The setting of the interface specification. (4) The decision of the relating conditions of the interface for CSFs (5) The comfort evaluation value of formula drawn from the interface specification. The comfort-structure evaluation formula developed was applicable for the practical use, i. e., get on or off of vehicles. As the result, the high correlation could be found between the comfort evaluation value and the subjective evaluation scale value, and its effectiveness and validity were approved.

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