The purpose of this experiment was to examine effects of a monotonous tracking task on eye fixation related brain potentials (EFRP). Ten subjects were assigned a monotonous task (96min) which was divided into 12 blocks. Each block consisted of a tracking task (5min) and a subjective questionnaire (3min). Eye movements and EEGs were measured during two probe tasks inserted before and after the monotonous task. EEGs were averaged at offset of saccades in order to obtain EFRP. As a result, error responses in tracking task, scores of feelings of fatigue and tedium increased, but scores of arousal and concentration decreased during the task. The most prominent positive component with latency of about 100ms in EFRP was compared between two probe tasks before and after monotonous task. The amplitude after the monotonous task decreased than before the task. The results suggested that EFRP was a useful index of the mental work load.

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The training system using the active controller that had the force displayed function is propose in the previous paper, and it is suggested that the active controller is useful to a novice in the improvement of the acquirement speed, etc. In the present paper, the training effect using the active controller is examined by the manipulated variable and the weighting matrix on the quadratic performance index. The analysis of these experimental data indicates that the trainees are able to acquire the control variable that is force-displayed through the active controller. From this result, the other training, in which the force-displayed control variable is changed into the one that resembled the well-trained operator's manipulation from the one that resembled the novice's manipulation in the acquirement process, is performed. As the results, it was confirmed that this training method improved the training effect and the training load for the trainees, in comparison with the conventional training method having displayed only the fixed force-displayed control variable that resembled the well-trained operator's manipulation. Lastly, the training, in which the force-displayed control variable was transformed into the visual display from the force display, was examined, and it was shown that the training effect was obtained by the force display compared with the visual display.

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This paper describes biomechanical properties of dynamic muscle contraction against viscosity resistance referred to as the “isoviscous contraction”, by means of comparison with the isotonic and isokinetic muscle contraction. For the experiment a loading system composed of a directly-driven electromagnetic motor and electronic control circuit was developed to be enable to perform three patterns of dynamic contractions, and the torque and joint angle were obtained during knee extension of 8 healthy male volunteers. Compared with isotonic and isokinetic contraction, in the isoviscous contraction, it is able to perform instructed movement in the wide range of joint motion at all the levels of contractions, and is not observed any steep increase of the angular velocity and the torque as seen in others. The isoviscous contraction is considered to be a useful way for rehabilitation or training in disabled patients and aged people. However, because of its inertial force elicite from isoviscous contraction, it is suggested that it should be compensated for evaluating of dynamic force ability.

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This paper proposes maneuverability indexes for a control stick that are based on considerations of muscle characteristics. The indexes are defined on the basis of muscle forces: stiffness of the musculoskeletal system and torque for accelerating the stick. Measuring muscle forces with electromyography, we examine the effectiveness of the proposed indexes in a tracking operation experimentally. In a slow tracking control with a frequency below 0.5Hz, the index based on stiffness conforms to the subjective evaluation, but the index based on the torque is inadequate as an index of maneuverability; we therefore use the index based on stiffness as the maneuverability index. We also examine the effect of controlled object dynamics and find that the index is in good agreement with the subjective evaluation. As a result, it is shown that the index can indicate the maneuverability in the low-frequency tracking operation of the stick.

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