A Low-Power, IP68-Compliant, BLE-Based Multi-Station Smart Irrigation Control Unit for Agricultural Applications

This study designs, develops, and evaluates the performance of a low-power, Bluetooth Low Energy (BLE) based, IP68 protection-rated, multi-station smart irrigation control unit for agricultural irrigation applications. The system is built on an STM32F103 microcontroller-based electronic control board and can manage 6 independent irrigation stations. Irrigation is automatically controlled by evaluating environmental data obtained from rain, frost, and wind sensors, and it is designed to be compatible with different types of rain sensors. Thanks to the user-definable cycle & soak algorithm, irrigation is performed in specific cycles, and a waiting period is applied after each cycle to allow the soil to absorb the water, aiming to increase water use efficiency. The control unit can be managed remotely from mobile devices compatible with common mobile operating systems via a mobile application using BLE technology, up to approximately 15 m; irrigation schedules can be created, past irrigation records can be viewed, and manual control operations can be performed remotely. The system is designed to operate with a 9V alkaline battery (550 mAh), offering approximately 6 months of continuous operation with a single battery and approximately 1 year with two batteries. The improved control unit, with its IP68 protection class housing, provides high durability against harsh environmental conditions. Its multi-station structure, low power consumption, and user-friendly features offer an integrated solution for smart irrigation applications.