The device uses 3 different ambient sensors and data-smoothing procedures to accurately detect human presence and avoid false-positives:
- HCSR501 passive infrared sensor
- BH1750 ambient light sensor
- HCSR04 ultrasonic distance sensor
On the first run the device sets itself as a Wi-Fi access point, providing an user-friendly web interface to program the device:
- connection to existing wireless network
- MQTT protocol setup
No further setups are needed, settings are saved persistently on the device
The device has a single button to control it:
- short press
<1s no feedback- toggle the lights
- long press
>5s blinking led feedback- toggle sensors automation
- very long press
>10s stationary led feedback- factory reset
Further iterations will implement a rotary encoder for manual brightness control
As a MQTT client the device is fully IoT capable and easily implementable in common home-automation systems and services. Given the MQTT broker settings and the device main_topic (E.g. room of operation), the device will automatically set its own topics as follows:
main_topic/device_id/lights/statusmain_topic/device_id/sensors/status
The device subscribes to lights and sensors topics to accept commands (such as brightness control, etc.) and publishes its own status updates in the status sub-topics
External dependencies / many thanks to:
- BH1750 by claws
- HCSR04 by martinsos
- WiFiManager by tzapu
- arduino-mqtt by 256dpi