著者

新川 拓也 河内 了輔

出版者

公益社団法人 日本生体医工学会

雑誌

生体医工学 (ISSN:1347443X)

巻号頁・発行日

vol.44, no.1, pp.94-100, 2006 (Released:2008-02-27)

参考文献数

12

被引用文献数

2

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The aim of this research is to develop a human-computer interface system for quadriplegic patients. In this study, we developed a two-channel human-computer interface system for inputting characters of the Japanese language using mandibular and tongue movement. The interface consists of a polymer mouthpiece and a slide potentiometer. Operation involves the user looking at character patterns displayed on a PC screen and selecting elements by making a 'biting' movement with the upper and lower incisors. The final selection of a character element is made by pushing a switch with the tip of the tongue. The display is a two-dimensional matrix composed of 50 syllables of the Japanese alphabet, as well some symbols used in writing. The operator first selects the line of the character element, and then the column corresponding to the element of choice. The illumination of a pilot lamp provides the user with a visual means of confirming the exact position of the character element selected. The time taken for the whole operation was recorded. Two subjects carried out the experiments over a period of three days. It was possible to input Japanese syllables in about 4 s.

著者

新川 拓也 河内 了輔 萩野 知香 西 恵理 高田 慶応 湊 小太郎

出版者

一般社団法人 日本生体医工学会

雑誌

生体医工学 (ISSN:1347443X)

巻号頁・発行日

vol.49, no.3, pp.501-507, 2011

被引用文献数

1

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The aim of this study was to clarify the mechanical action of the infant tongue during sucking. Therefore we developed an artificial nipple that contained multiple small built-in force sensors which was capable of measuring tongue-artificial nipple contact pressure in real-time. A force sensor was a cantilever structure composed of a thin stainless steel beam and all-purpose foil strain gauges attached to the surface of the beam. The signals obtained from the force sensor were amplified, and were transferred to a PC via a USB port. Using this system, measurements were taken in three infants. The output waveform was observed in all subjects, and the rate of sucking was about two times per second. In addition, the pressure waveform indicated peristalsis-like movement of tongue in infants with established oral feeding. This system can quantitatively measure individual differences in tongue movement.

著者

河内 了輔 新川 拓也 河原崎 景太 藤川 智彦 武井 安津子 湊 小太郎

出版者

公益社団法人 日本生体医工学会

雑誌

生体医工学 (ISSN:1347443X)

巻号頁・発行日

vol.50, no.6, pp.564-570, 2012-12-10 (Released:2013-07-31)

参考文献数

12

被引用文献数

1

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In this study, we developed a point-contact force sensor, and this sensor was used to develop a measurement system that was shaped in the form of a feeding bottle. Unlike in a cantilever force sensor, in the proposed force sensor, the point of force measurement does not move. Thus, the force sensor can measure a force at a specified point. The force sensor consists of a pressure transducer and a steel ball with a diameter of 3 mm. Any force applied to the artificial nipple is transmitted to the pressure transducer, which is in point contact with the steel ball. The force sensor is linear up to a load of 3.92 N, has a hysteresis of 1%, and has a response time of 4 ms. The force is measured at distances of 8 mm (channel 1) and 14 mm (channel 2) from the tip of the nipple. In the measurement system, the sensor signals are converted (A/D) at a sampling rate of 100 Hz and a quantization resolution of 10 bits. After the A/D conversion, the force signals are transferred to a data indicator and a data logger for real-time display on an LCD and for storage ona micro SD card, respectively. Using this system, we performed measurements on four infants. A signal peak was observed from channel 2 and then from channel 1. This result could be attributable to the peristaltic movements of the infant's tongue. The same result was observed for all subjects. These results indicate that the proposed system can be used to measure any force that is applied to an artificial nipple. Moreover, the mother of a subject also performed measurements using the system. This confirmed that the system was easy to operate and that measurements could be performed in a normal feeding posture.