MEAM Seminar: “Design, Characterization, and Fabrication of Low-Cost, Passive, and Biodegradable Sensors for Precision Agriculture”

With the global population projected to reach 9.1 billion people by 2050 there is a need to develop highly efficient agricultural systems that can reliably maximize crop yield. Precision Agriculture (PA) systems enabled by the Internet of Things (IoT) offer a potential solution through improvements in labor, resource, and time efficiency to improve agricultural output. PA systems enable this by providing a detailed understanding of the state of the field (e.g., soil moisture, pH, temperature, etc.) so that these resources can be properly deployed spatially and temporally. To realize these systems, sensors that give information about the state of the field are required. However, for the technology to be scalable and practically implemented, these sensors must balance performance and cost. These requirements limit the materials and methods that can be used to develop the technology, including many that are common in modern sensor development. Additionally, the challenge of biocompatibility and biodegradability must be addressed.In this talk, a passive RF sensing system is presented for the detection of soil moisture. This sensing system is developed on a fully biodegradable cellulose nanofibril (CNF) based composite substrate that can used for the rapid fabrication of high fidelity electrical structures via screen printing. The surface, electrical, and diffusion properties of the substrate are characterized. By utilizing screen printing, capacitive structures are fabricated that can detect moisture content over a wide range of humidity and soil moisture conditions.