A biodegradable chipless sensor for wireless subsoil health monitoring

Abstract

Precision Agriculture (PA) is an integral component of the contemporary agricultural revolution that focuses on enhancing food productivity in proportion to the increasing global population while minimizing resource waste. While the recent advancements in PA, such as the integration of IoT (Internet of Things) sensors, have significantly improved the surveillance of field conditions to achieve high yields, the presence of batteries and electronic chips makes them expensive and non-biodegradable. To address these limitations, for the first time, we have developed a fully Degradable Intelligent Radio Transmitting Sensor (DIRTS) that allows remote sensing of subsoil volumetric water using drone-assisted wireless monitoring. The device consists of a simple miniaturized resonating antenna encapsulated in a biodegradable polymer material such that the resonant frequency of the device is dependent on the dielectric properties of the soil surrounding the encapsulated structure. The simple structure of DIRTS enables scalable additive manufacturing processes using cost-effective, biodegradable materials to fabricate them in a miniaturized size, thereby facilitating their automated distribution in the soil. As a proof-of-concept, we present the use of DIRTS in lab and field conditions where the sensors demonstrate the capability to detect volumetric water content within the range of 3.7–23.5% with a minimum sensitivity of 9.07 MHz/%. Remote sensing of DIRTS can be achieved from an elevation of 40 cm using drones to provide comparable performance to lab measurements. A systematic biodegradation study reveals that DIRTS can provide stable readings within the expected duration of 1 year with less than 4% change in sensitivity before signs of degradation. DIRTS provides a new steppingstone toward advancing precision agriculture while minimizing the environmental footprint.

Wireless Battery‐Free Flexible Sensing System for Continuous Wearable Health Monitoring

“…Wireless battery-free flexible sensing systems enable contactless conversion of various human physiological parameters for medical diagnosis. [6][7][8][9] However, the integration of multiple wireless sensors into the wearable system remains three key challenges to address. First, current wireless multiparameter monitoring sensors with a rigid substrate are mostly directly multiple human physiological parameters simultaneously.…”

A new paradigm of reliable sensing with field-deployed electrochemical sensors integrating data redundancy and source credibility

“…In contrast, relatively small sample volume and rapidly varying temperature, humidity, and target concentration increase noise and decrease data reliability of the sensors used in the field 8 . Time-dependent Degradation: Water ingress, biofouling, radiation exposure, etc., change the physical and chemical properties of the sensor 9 , 10 . As a result, sensor performance degrades over time when exposed to the natural environment.…”

“…Time-dependent Degradation: Water ingress, biofouling, radiation exposure, etc., change the physical and chemical properties of the sensor 9 , 10 . As a result, sensor performance degrades over time when exposed to the natural environment.…”

Low-Cost Nonreversible Electronic-Free Wireless pH Sensor for Spoilage Detection in Packaged Meat Products

“…On the other hand, chip-less designs focus on simpler yet accurate measurements in order to eliminate the need for intricate electrical components . pH-responsive elements have been used in many designs toward passive actuation. − In some designs, the response from a pH-sensitive coating on a chip-less sensing coil is measured wirelessly as shifts in RF peak intensity by an interrogating antenna .…”