Embedded BLE Irrigation Controller

Innards of Enclosure Electrical Box

Project Overview

This BLE-enabled irrigation controller is based on the ESP32-C3 microcontroller platform and provides automated control of solenoid valves for residential or backyard irrigation systems. The controller supports both scheduled and manual operation via a custom Flutter mobile application. Time synchronization is achieved through SNTP over Wi-Fi, with a DS3231 RTC module providing local fallback. The system integrates real-time control, wireless communication, and a mobile UI into a compact embedded solution.

Hardware Design

The electronics include an ESP32-C3 module, relay drivers for valve control, and a real-time clock module. Snubber circuits are installed across relay contacts to mitigate flyback voltage from inductive loads. Power is provided by a 24 V transformer for solenoid valves, with an AC/DC adapter supplying the ESP32 and control circuitry. Manual override switches are included to allow direct operation of the valves without the app.

Enclosure & Mechanical Integration

The ESP32 and peripheral components are housed in a custom 3D-printed PETG enclosure designed in FreeCAD. This enclosure fits within a standard weather-proof electrical box, allowing for protection from the elements and easy deployment. Cable management ensures safe routing of power and signal lines, and the overall form factor is compact to minimize footprint in the installation area.

Software & Control

The firmware running on the ESP32-C3 handles BLE communication, valve actuation logic, and time synchronization. The Flutter mobile application enables users to configure schedules, trigger manual valve operation, and monitor system status remotely. The system architecture emphasizes modularity, with clear separation between hardware control, communication stack, and user interface.

Next Steps

Future improvements include implementing sensor feedback for soil moisture to enable automated irrigation based on real-time conditions, improving power efficiency, and adding logging for usage and diagnostics.