The investigation of natural-rubber for improving self-powered heat detector based on thermoelectric generators

Abstract

Fire hazard has destroyed humanity creations. Fire detectors have been developed by using different techniques. Thermoelectric generator (TEG) is a part of energy harvesting which is able to convert heat into electricity because of temperature difference between hot and cold side of thermoelectric device (TE). Different materials are used for thermoelectric generators which depend on the characteristics of the heat source, heat sink and the design of the thermoelectric generator. Many thermoelectric generator materials are currently undergoing research. This paper presented an investigation of seeking an alternative way of detecting fire hazard by developing architecture prototype of a fire detection technique using natural rubber. The thermoelectric prototype used self-powered device which improved the temperature difference gap and stabilized the cold side of TE alongside natural rubber as the cooling material. The technique is relatively simple system realization based on three viable components, i.e. a heat sensor, a low-power RF-transmitter and a RF-receiver. The heat sensor is designed and fabricated by thermoelectric and heat sink with natural rubber (NR) coating. The NR coating is heat absorption reduction. Therefore, the temperature difference is wildly resulting in the higher TE output voltage. The voltage is also supplied to the low-power RF transmitter module. In case of fire hazard, the temperature increases from 26 to 100 °C , the prototype can operate successfully. This technique will solve potentially the power supply issue in fluctuated situations. The rubber coating from rubber trees in Thailand would be a value chain added for bio-economy, supporting a sustainable development goal of the country

The development a fully-balanced current-tunable first-order low-pass filter with Caprio technique

“…Equation (8) shows that the corner frequency can be adjusted by bias, the current I f value, as it is named «current-tunable low pass filter».…”

“…The filter circuit can be further divided into four functional types, Low pass filter: LPF, High pass filter: HPF, Band pass filter: BPF, Notch filter or Eliminate filter: BEF and Low-pass filters are important and have a wide range of applications. For example, in mobile communication systems analog signal processing and in biomedical systems [2][3][4][5][6][7][8]. The low-pass filter to detect biological signals generally uses a voltage in the range of 1V-100 mV and a cut-off frequency below 100 Hz [9][10][11][12][13].…”