Takeshi Tsuruga

A basic study for a robotic transfer aid system based on human motion analysis

A metal hydride (MH) actuator uses the reversible reaction between heat energy and mechanical energy of a hydrogen-absorbing alloy and moves smoothly without any noise. Moreover, the actuator is compact, light and has adequate compliance. In this paper, some experiments concerning human motion patterns were carried out in order to adopt the MH actuator to the transfer aid system. The results were evaluated from a biomedical engineering viewpoint in order to obtain the optimal parameters for transferring the disabled from a bed to a wheelchair and vice versa (transfer aid). Sagittal plane kinematics, surface electromyographic signals (EMG) obtained from lower limbs, ground reaction forces and foot pressure distribution were measured using a three-dimensional motion analyzer. From the experimental results, it was found that the motion of the transfer aid was smooth when the initial angle of the ankle was 70°. The best initial angle of the trunk was also found to be about 45° while standing from a bed. However, the initial angle of the trunk was best at 60° when a person was in the process of sitting down on a wheelchair. Furthermore, a knee pad which supports the lower limbs requires flexibility in the range of 0.1-0.2 kgf/mm.

Basic Study for New Assistive Technology Based on Brain Activity During Car Driving

Recently, it is necessary to develop a new system which assists driving car and wheelchair as aged society. The final our purpose in this research is to contribute to developing of assistive robot and related-apparatus. In terms of developing a new system, we thought that it is important to examine behaviors as well as spatial recognition. Therefore, experiments have been performed for an examination of human spatial perceptions, especially right and left recognition, during car driving by using NIRS. In previous research, it has been documented that there were significant differences at dorsolateral prefrontal cortex at left hemisphere during virtual driving task and actual driving. In this paper, we performed measuring the brain activity during car driving by using NIRS. And we performed statistical analysis of the brain activity. The purpose of this paper is discovering the brain region which was involved in decision making when human drive a car and considering between human movement and brain activity during car driving. Keywords—brain information processing during driving task; spatial cognitive task; determining direction; NIRS

Attempts to Quantitative Analyze for the Change of Human Brain Activity with Physical and Psychological Load

Recently, Japan (also world-wide countries) has become aged society, and a wide variety welfare device and system have been developed. Various companies are trying to enter the welfare device and system. Successful cases of the attempt are rare. There are several problems. For example, it is difficult to sell to the user because it does not known the effect. Thus, the direction of development is hard to determined. Because there is no evaluation method is the main cause of those. Evaluation of welfare system and device are limited only stability, intensity and partial operability. So, evaluation of usefulness is insufficient. Therefore, we will attempt to establish the standard to evaluate usefulness for objectively and quantitatively on the basis of including non-verbal cognition. In this paper, we measure load of sitting and standing movement to use Electoromyogram (EMG) and 3D Motion Capture and set a goal to establish objective evaluation method. We think that establishing objective evaluation method is necessity to develop useful welfare device. We examined possibility of assessing load and fatigue from measuring brain activity to use Near Infra-Red Spectroscopy (NIRS). The idea of universal design is widespread in welfare device and system. Measuring requires verification of all generations. But, we performed to measure younger subjects as a first step. We think that younger subjects were observed the significant difference, because they had enough physical function. Considering younger subjects as a benchmark is appropriate for creating evaluation method.

Consideration of Measuring Human Physical and Psychological Load Based on Brain Activity

In Japan and developed countries, it has become aged society, and wide variety welfare device or system have been developed. But these evaluation methods of welfare device or system are limited only stability, intensity and partial operability. Because of, it is not clear to determine the standard to evaluation for welfare device or system of usefulness. Therefore, we will attempt to establish the standard for evaluation about usefulness for objectively and quantitatively for including non-verbal cognition. We examine the relationship between human movements and brain activity, and consider the evaluation method of welfare devices and systems to measure the load and fatigue which were felt by human. In this paper, we measure the load for sitting and standing movement using NISR. We tried to make sure for the possibility of the quantitatively estimation for physical or psychological load or fatigue by measuring of brain activity using NIRS (Near Infra Red Spectroscopy). As results, when subjects perform the movement task, the statistical significant difference was shown in the specific part of the brain region.

A basic study for a robotic transfer aid system using a high power MH actuator

In this paper, some experiments concerning the human motion pattern were carried out and the results were evaluated from a viewpoint of biomedical engineering in order to obtain the optimal parameters for the transfer aid. Sagittal plane kinematics, surface electromyographic signals (EMG) obtained from lower limbs, ground reaction forces and foot pressure distribution were measured using a 3 dimensional motion analyzer. From the experimental results, it was found that the motion of the transfer aid was smoothly moved when an initial angle of the ankle was 70/spl deg/. The initial angle of the trunk was also found to be the best about at 45/spl deg/ while standing from a bed. The initial angle of trunk was the best at 60/spl deg/ while sitting down to the wheelchair. Furthermore, a knee pad which supports the lower limbs needs the flexibility in the range from 0.1 to 0.2 kgf/mm. From the above results, some parameters for the design of the transfer aid system were determined. In our transfer aid, a high power MH actuator was adopted since the actuator can smoothly move the transfer arm. The MH actuator uses the reversible reaction between heat energy and mechanical energy of a hydrogen absorbing alloy. Therefore, the MH actuator works smoothly without any noise. Moreover, the actuator is compact, light, and has an adequate compliance.