Smart-Waterer – Intelligent Plant Watering System

Smart-Waterer is an ESP32-based system designed to automate the watering of potted plant at home. It combines real-time soil moisture monitoring with web control, allowing both automatic and manual watering through a REST API. Currently, ESP32 works in WiFi AccessPoint mode, but we plan to enable its connection to an existing network (station mode)

---

System Architecture

The system is built in a real-time operating system (RTOS). It consists of several main elements:

• taskReadHumiditySensor: humidity reading from ADC
• taskMakeDecisionToWater: automatic watering management
• taskWaterPump: support for switching on the pump for a specified time
• watering_queue: queue of watering signals read by taskWaterPump
• humidity_queue: queue of current humidity readings
• user_config: user configuration structure

The http server is configured on the esp32. Following REST endpoints have been implemented:

• GET / – download the html+css+js page with the user interface,
• GET /api/humidity – download the current humidity,
• POST /api/water – manually start watering,
• GET /api/config – download the current configuration,
• POST /api/config – save the new configuration.

From the webpage we can change user configuration structure, which consists of the following settings:

• watering_time: Watering duration in milliseconds.
• watering_interval: Minimum time (in milliseconds) between watering cycles.
• sample_count: Number of moisture measurements to average.
• read_delay: Time in milliseconds between moisture measurements.
• dry_threshold: Moisture threshold (%) below which watering is triggered.

The user configuration structure is read at program startup and saved to NVS memory each time the user changes the configuration.

The web page returned using a GET / request is currently embedded in the code as a single string, but in the future we plan to use the SPIFFS file system to store the web page as a separate file.

---

Screenshots

Prototype

Web Dashboard view

---

Board Schematic

TO-DO

---

PCB View

TO-DO

---

Technologies Used

• ESP32-WROOM-32 – Dual-core 32-bit microcontroller used as the main controller.
• ESP-IDF – Official Espressif development framework for writing ESP32 firmware in C/C++.
• ESP-IDF FreeRTOS – Real-time operating system for managing multitasking on ESP32.
• html+css+js – Used to create a website hosted by esp32
• Altium Designer – Used for designing the device's PCB and schematics.

---

Getting Started

Requirements

• ESP32-WROOM-32 development board
• ESP-IDF environment set up

Build & Flash (Firmware)

1. cd esp32_firmware
2. idf.py build
3. idf.py -p /dev/ttyUSB0 flash monitor

---

Contact

For questions or contributions, feel free to open an issue or pull request!