Fundamental Study on Walking information and Guidance Systems for The Blind and The Elderly Using Faint Electric Waves

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Much information has been obtained through our fundamental researches on the information and guidance systems which assist the blind and the elderly in walking alone on the streets using faint electric waves. The researches were broadly divided into two fields. One was the investigation of consciousness and training of the blind to walk for making a psychological map, and the other was the analysis of mutual relation characteristics between the output strength of an electric field and the sound pressure which were needed to collect information from a handy radio.1. The psychological mapThe consciousness about obstacles to walk, landmarks,ascent and descent at station public transportation mode and necessary information to walk were investigated. these were done with the cooperation of the students at a school for the blind. Very important walking information has been obtained from the study. Furthermore, an appearance of training to walk on a street from a subway station to a prefectur … More al library for generally blind men was recorded on a video camera and a process of training to walk by a trainer was also recorded on tapes. From the analysis of the data recorded from the study, walking characteristics of the blind have been clarified.The kind of information and a method of offering it which were needed to make a psycho-logical map have been clarified. In addition, a method to make a psychological map into a manual has become definite. In this study, from an opinion that surface information is more important than guidance, making the psychological map to offer the information by the use of faint electric waves which is listened within few meters radius is the principal objective.2. Mutual relation characteristics between output strength of electric field and the sound pressureMutual relation between output strength of electric field of the faint electric waves and the sound pressure of radio (under constant volume) which teceives this waves is important, because handy radio used in our study did not have AGT. As a result of our experimentations, the output of the sound pressure from the radio did not change within 5 meters radius even when the output strength(dB) of the faint electric waves from the transmitter was less than 60 dB. On the other hand,it turned out that the voice could not be listened from the radio,because the output strength of the faint electric waves rapidly decreased over 5 meters radius, and proportionally the sound strength also decreased. Less