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Near Infra-Red Spectroscopy (NIRS) is possible to measure brain activity signals with low invasive and low physical restraint, so it is also expected as a useful clinical tool in the fields of medicine and education. However, measurement and detection of weak signal of brain activities such as human intention and recall of memory, is very difficult because noise signals such as heartbeat, respiration, and body movement disturb the brain activity signal and data. In this study, we attempt to reduce the effect of the artifacts ingredient by the body movement from the data of NIRS using the Auto-Regressive (AR) model. From the experimental results, we confirmed that the peaks of FFT analysis of brain activity measurement data and ECG data were almost identical. Particularly, characteristic peaks around 0.5Hz and 1.3Hz were detected. The peak around 0.5Hz was effected based on position change of the head inclining. The peak around 1.3Hz was effected based on the periodical R wave in the ECG data. Also, AR model was estimated from AR coefficients by the above results. So, we could separate the component of artifacts based on heartbeats and separate the component of artifacts based on positioning change of the head inclining, from the brain activity signals. It means that using AR model from the brain activity measurement data by NIRS, we could reduce the effects of artifacts based on heartbeats and reduce the effects artifacts based on position change of the head inclining. In the future, we will reduce other artifacts based on other factors. Moreover, using this proposed methodology, we try to improve brain region identification and statistical accuracy which could not be clarified by conventional experimental methods.

Recently, Japan (also world-wide countries) has become aged society, and a wide variety welfare device and system have been developed. But evaluation of welfare system and device are limited only stability, intensity and partial operability. Thus, evaluation of usefulness is insufficient. Evaluation of usefulness is necessity to consider about interaction of human and welfare device. In this paper, we measure load of sitting and standing movement to use EMG (Electromyogram) 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 NIRS (Near Infra-Red Spectroscopy). We think that measuring load and fatigue is very important for developing user-friendly welfare device. Idea of universal design is widespread in welfare device and system. Measuring require verification of all generations. However, 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.

Visually impaired persons recognize their surrounding with a white cane or a guide dog while walking. This skill called "Orientation and Mobility" is difficult to learn. The training of the "Orientation and Mobility Skills" is performed at the school for visually impaired person. However, the evaluation of this skill is limited to subjective evaluation by teacher. We have proposed that quantitative evaluation of the "Orientation and Mobility Skills" is required. In this paper, we tried to execute the quantitative evaluation of the "Orientation and Mobility Skills" using brain activity measurements. In this experiment, brain activity was measured when subjects are walking in the corridor alone or with guide helper. Experimental subjects were sighted person who was blocked visual information during walking. The blood flow of prefrontal cortex was increased as the movement distance of the subject increased when subjects walk alone. From this result, it can be considered that the feeling of fear and the attention relayed to "Orientation and Mobility Skills" could be measured quantitatively by measuring human brain activities.

Recently, in developed countries, especially in Japan, the population of elderly people are increasing. Physical function of elderly people deteriorates due to age, it causes stumble accident. A stumble accident of an elderly people leads to a bone fracture. In elderly people, it is very dangerous to become bedridden by bone fractures and injuries. Thus, it is important for elderly people to prevent stumble accident. The "Base of support" (BoS) has been reported to be related to stumble accident. We have been executing experimental consideration regarding stumble accident and BoS. In this study, we executed measurement and analysis of walking movement for human and analyzed based on the dynamic change for BoS. This experiment, we measured and analyzed walking movement using optical and inertial sensor type motion analysis device. In addition, we measured the step length using the camera. The Subjects walked straight for approximately 10 m indoors. Moreover, they executed heel strike according to the timing when the metronome sounds. Also, we changed the rhythm of the metronome every 10 bpm from 90 bpm to 140 bpm. As for experimental results, the dynamic change of BoS increased as walking rhythm changes faster. This is considered to be increasing movement of gravity center of human body. In this study, we executed measurement and analysis of walking movement for human and analyzed the dynamic change for BoS. However, it is considered necessary to reconsider the contents of the experiment. In the future, we aim to establish an index of the dynamic stability evaluation of human walking movement.