Research Of Information Fiber-based Flexible Sensor Theory And Applications

Flexible sensors are necessary to information sensing of intelligent clothes system. This research will investigate sensing mechanism, input-output relationship and parameters ranges of information fiber-based flexible sensors, which is benefit to ECG, respiration, temperature and pressure measurements for the intelligent clothes system.Theory and technology of mathematical model of fiber formation, information fiber and flexible sensor design have been summarized.Time-domain mathematical model of fiber formation has been fabricated based on physical laws. The relationship of time-domain mathematical model and frequency-domain mathematical model has been induced.Flexible woven resistive strain sensors made of electrical conductive elastic fibers have been designed. The electrical equivalent circuit model of both parallel strain sensor (PSS) and series strain sensor (SSS) have been fabricated, where the weft of PSS are in parallel connection and that of SSS are in series connection. The strain-resistance relation and input-output properties of both PSS and SSS are deduced based on the electrical equivalent circuit model and physical laws. Parameters domains (sets of effective value) of size, fiber radius and resistivity have been investigated. Results indicate that the parameters domains of both PSS and SSS are of three-dimensional space limited by one surface and five planes. PSS is desired to be made of electrical conductive elastic fibers with a moderate or low resistivity and be applied to strain measurement for any scale objects theoretically, while SSS is desired to be made of electrical conductive elastic fibers with a low resistivity and be applied to strain measurement for small-scale objects only. Flexible woven resistive temperature sensors made of electrical conductive fibers have been designed. The electrical equivalent circuit model of both parallel temperature sensor (PTS) and series temperature sensor (STS) have been fabricated, where the weft of PTS are in parallel connection and that of STS are in series connection. The temperature -resistance relation and input-output properties of both PTS and STS are deduced based on the electrical equivalent circuit model and physical laws. Parameters domains (sets of effective value) of size, fiber radius and resistivity have been investigated. Results indicate that the parameters domains of both PTS and STS are of three-dimensional space limited by one surface and five planes. PTS is desired to be made of electrical conductive fibers with a moderate or low resistivity and be applied to temperature measurement for any scale objects theoretically, while STS is desired to be made of electrical conductive fibers with a low resistivity and be applied to temperature measurement for small-scale objects only.Flexible woven resistive pressure sensors made of electrical conductive fibers have been designed. The electrical equivalent circuit model of both parallel pressure sensor (PPS) and series pressure sensor (SPS) have been fabricated, where the weft of PPS are in parallel connection and that of SPS are in series connection. The pressure-resistance relation and input-output properties of both PPS and SPS are deduced based on the electrical equivalent circuit model and physical laws. The outputs of both PPS and SPS with random pressure distribution have been simulated. The range of pressure has been investigated; and parameters domains (sets of effective value) of size, fiber radius and resistivity have also been investigated. Results indicate that the effects of random pressure distribution can be neglected, and PPS has a better accuracy than SPS. Both PPS and SPS are desired to work in a relative 'small range'of pressure, and a range of relative'small pressure'. The parameters domains of both PPS and SPS are of two-dimensional plane limited by one curve and three lines. The weft of PPS is desired to be made of electrical conductive fibers with a moderate resistivity, while that of SPS is desired to be made of electrical conductive fibers with a low resistivity only. Flexible woven resistive penetration sensor made of electrical conductive fibers and its signal conversion circuit has been designed. The input-output model of the penetration sensor has been fabricated. The input-output properties of the penetration sensor have been investigated. The general rules of input status determination based on output status in typical applications have also been investigated.Flexible woven electrodes made of electrical conductive fibers have been designed. The distributive electrical equivalent circuit model of the woven electrodes and theirs mathematical model of ECG measurement have been fabricated, respectively. Effects of factors on ECG intensity have been simulated, and the parameters domains (sets of effective value) of size, fiber radius and resistivity have been investigated. Results indicate that it is more help to ECG measurement that the resistance of the woven electrodes is of moderate and that the contact resistance is of low, or both the resistance of the woven electrodes and the contact resistance are of low. There exists a best position where ECG intensity gets its maximum, while both the position and the maximum vary with the size of the woven electrodes. The design domain of the woven electrodes is of three-dimensional space limited by one surface and five planes. The woven electrodes are desired to be made of electrical conductive fibers with a moderate or low resistivity.Configuration of intelligent clothes system has been discussed. The model of intelligent clothes system incorporated in flexible sensors has been fabricated. Technical solutions of flexible woven electrode, flexible resistive strain sensor, flexible resistive pressure sensor, flexible resistive temperature sensor and flexible resistive penetration sensor have been designed from application point of view. Furthermore, technical solution of health monitoring clothes with flexible woven electrode, flexible resistive strain sensor and flexible resistive temperature sensor, and technical solution of electric heating clothes with flexible resistive temperature sensor, and technical solution of sleep positions monitoring clothes with flexible resistive pressure sensor, and technical solution of health monitoring military uniform with flexible resistive penetration sensor have also been designed, respectively.Finally, the conclusions are summarized and the next work of the research is prospected from great scope and depth point of view.