Journal of Sensor Science and Technology (센서학회지)

The Korean Sensors Society (한국센서학회)
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Refractive index-based soil moisture sensor

굴절률 기반 토양 수분 센서

  • Sim, Eun-Seon (Department of Creative Convergence, Hanbat National Unversity) ;
  • Hwa, Su-Bin (Department of Creative Convergence, Hanbat National Unversity) ;
  • Jang, Ik-Hoon (FarmAI Lab, Jinong) ;
  • Na, Jun-Hee (Department of Electrical, Electronics & Communication Engineering Edu., Chungnam National University) ;
  • Kim, Min-Hoi (Department of Creative Convergence, Hanbat National Unversity)
  • 심은선 (한밭대학교 창의융합학과) ;
  • 화수빈 (한밭대학교 창의융합학과) ;
  • 장익훈 ((주)지농 FarmAI 연구소) ;
  • 나준희 (충남대학교 전기전자통신공학교육과) ;
  • 김민회 (한밭대학교 창의융합학과)
  • Received : 2021.10.01
  • Accepted : 2021.11.15
  • Published : 2021.11.30
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Abstract

We developed a highly accurate, yet inexpensive, refractive index (RI)-based soil moisture sensor. To detect the RI, a light guide was set with a light-emitting diode and photodiode. When the air fills the space between the soil particles, most of the incident light is reflected at the interface between the waveguide and the air because of the large RI difference. As the moisture of the soil increases, the macroscopic soil RI increases. This allows incident light to pass through the interface. The intensity of the light reaching the photodiode was simulated according to the change in the soil RI. Using the simulation results, we designed and manufactured a curved glass waveguide. We evaluated the performance of the RI-based soil sensor by comparing it with a commercially available, high-cost and high-performance time-domain reflectometer (TDR). Our sensor was 96% accurate, surpassing the costly TDR sensor.

Keywords

Acknowledgement

이 논문은 2021년도 정부(산업통상자원부)의 재원으로 한국산업기술진흥원의 지원(P0012744, 2021년 산업혁신인재성장지원사업)과 한국연구재단의 지원(No.2018R1A6A1A03026005)을 받아 수행된 연구임.

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