Long-term assessment of event-based communication for irrigation control in a bell pepper farm

Abstract

This work describes the development and implementation of an event-based hysteresis controller for irrigation systems. Transmission of information from the farm is triggered attending to the instantaneous and accumulated change of moisture in the soil. The proposed methodology is assessed in a 3-month experiment in a bell pepper farm, which covers almost the entire agricultural campaign of this crop. The infrastructure, designed ad-hoc to test the methodology, consists in: edge sensing devices with capacitive soil moisture and irrigated volume sensors, edge device to actuate the electrovalve, LoRa communication, and cloud services for receiving and storing data, and for computing the control commands. The event-based policy is compared with a periodic scheme, achieving a reduction of 77% of transmissions, and increase of 11% in the battery lifespan, and achieving communication events with 4 times as much information transmitted. The hysteresis control yields a reduction of 9% of the water consumption compared to the manual irrigation of the farmer.