| Title | Improving a Dual-Probe Heat Pulse based soil moisture sensor using insulated nichrome wire |
| Publication Type | Conference Paper |
| Year of Publication | 2015 |
| Authors | Raman, A, Ananthasuresh, GK |
| Conference Name | Physics and Technology of Sensors (ISPTS), 2015 2nd International Symposium on |
| Date Published | March |
| Keywords | calibration, ceramic tube, ceramics, coatings, Dual-Probe Heat-Pulse, dual-probe heat-pulse technique, heat distribution, Heating, insulated nichrome wire, insulated wires, longitudinal hole, Low power, material selection method, moisture measurement, nichrome sensor, Nichrome Wire, packaging, packaging method, Parylene, parylene-coated nichrome wire, power 165 mW, power 350 mW, Probes, Resistance, soil, soil moisture sensor, temperature 1 K to 6.2 K, temperature measurement, Temperature sensors, wires |
| Abstract | The Dual-Probe Heat-Pulse technique has been widely used for in-situ moisture sensing. In the heater probe described in our earlier work the power consumption was 350 mW-the lowest in this category of sensors. In this paper, by employing a material selection method, we further improve the performance of the sensor by employing Parylene-coated nichrome wire and different packaging methods. The power consumption is reduced to 165 mW with a temperature rise between 1 K to 6.2 K degrees in 34% wet and dry red soils, respectively. A variant of the nichrome sensor was one that employed a ceramic tube with four longitudinal holes that eliminated the need for Parylene coating. The sensor was verified in agar agar solution and calibrated with 1200 kg/m2 red field soil. The compact packaging of the nichrome heater allowed us to provide a heat distribution of 3267 J/m on the probe surface which is two times more than the earlier attempts. |
| DOI | 10.1109/ISPTS.2015.7220130 |
