Gate Guardian

Automating the Sommer Twist 350 Swing Gate with ESP32 and MQTT

This repository contains the design and code for Gate Guardian, an ESP32 swing gate controller designed to operate and monitor a Sommer Twist 350 swing gate. The system integrates remote control via MQTT over Ethernet, real-time status monitoring, and visual feedback. The design emphasizes reliability, safety, and ease of installation.

Changelog

v1.1

• Changed pins for status LEDs as these were input only:
  • Red LED: GPIO 17 (from GPIO 39)
  • Green LED: GPIO 5 (from GPIO 36)
  • Photo eye: GPIO 36 (from GPIO 5)

v1.0

• Initial release

MQTT Configuration

MQTT Topics

gateguardian/state = CLOSED
gateguardian/sensor/lock = 0
gateguardian/sensor/lights = 0
gateguardian/sensor/photo_eye = 0
gateguardian/sensor/external_relay = 0
gateguardian/client_id = esp32_gate_FFAA00
gateguardian/uptime = 1510
gateguardian/in_motion = 0

MQTT Commands

gateguardian/command = OPEN
gateguardian/command = CLOSE
gateguardian/command = STOP

Home Assistant Configuration

The Home Assistant configuration can be found here.

Schematics and PCB

Used LibrePCB to design the schematics and PCB.

Gerber files for the PCB can be found here.

Input/Output

Pin	Direction	Function	Note
GPIO 12	Output	Gate Close Relay	Pulse to close the gate
GPIO 14	Output	Gate Stop Relay	Pulse to stop the gate
GPIO 15	Output	Gate Open Relay	Pulse to open the gate
GPIO 17	Output	Red LED	Blinking during closing, solid during opening
GPIO 5	Output	Green LED	Blinking during opening, solid during closing
GPIO 33	Input	Gate Lights	Blinking warning light when opening or cloing
GPIO 32	Input	Gate Lock	Enabled when gate is closed
GPIO 35	Input	External Relay	Triggered when gate is closed
GPIO 36	Input	Photo eye	When someone/omething goes through the gate
GPIO 4	Input	Sensor 1	Optional sensor (dht22 temperature sensor)
GPIO 2	Input	Sensor 2	Optional sensor (not used)

Code

The firmware is built on the Arduino framework using PlatformIO and implements a robust gate control system with the following key features:

• MQTT Integration: Remote control and status monitoring via MQTT over Ethernet (W5500)
• Visual Feedback: Dual LED system (red/green) indicating gate state with blinking patterns during movement
• Position Sensing: Real-time gate position detection using magnetic sensors
• Safety Features: Relay pulse timing, state machine logic, and operation timeouts
• Diagnostics: Serial output at 115200 baud for debugging and monitoring

Platform IO Setup

pyenv local 3.13
python -m venv .venv
source .venv/bin/activate
pip install -r requirements.txt

Build

pio run

Test

pio test -v -e native

Run a single test:

TEST_FILTER=test_open_cycle pio test -v -e native

Upload (Serial)

pio run --target upload -v

OTA (Over-the-Air) Update

The firmware includes ElegantOTA for wireless firmware updates over the network.

1. Open a browser and navigate to http://<device-ip>/update
2. Authenticate with the configured OTA_USERNAME and OTA_PASSWORD
3. Select the firmware binary (.pio/build/esp32/firmware.bin) and upload

OTA credentials are set as compile-time build flags in private_config.ini:

'-D OTA_USERNAME=youruser'
'-D OTA_PASSWORD=yourpassword'

Web Interface

The device runs an HTTP server on port 80 with the following endpoints:

Endpoint	Description
/	Device identification
/gate/open	Command gate to open
/gate/close	Command gate to close
/gate/stop	Command gate to stop
/update	ElegantOTA firmware update page

MQTT Sequence Recording

To capture live gate behaviour as a test sequence, enable recording in private_config.ini:

-D MQTT_SEQUENCE_RECORD

Then subscribe to the recording topic:

mosquitto_sub -h <broker> -p <port> -u <username> -P <password> -t gateguardian/sequence

Each received line is a CSV row ready to paste into a new test/sequences/*.csv file. Prepend the header:

timestamp_ms,sensorLock,sensorLights,sensorPhotoEye,sensorExternalRelay,expectedState