I would like to create an ESPHome based Smoke Alarm… crazy or not?
The idea is that it would be a multisensor using:
based on an existing smoke sensor?
a MQ135 as Smoke Sensor?
the MAX30105 optical smoke sensor (problem is that the algorithm is closed source and not available at this moment. See (https://hackaday.io/project/18518-iteration-8/log/55721-a-first-attempt-at-figuring-out-the-max30105-air-particle-sensor)
CO Sensor: a MQ7 sensor which reads CO levels
Temperature and air quality: using the BME680 we can read the temperature, humidity and indoor air quality
Presence sensor: using the BLE beacon advertising, we know in which room we are. Hopefully, some day we could have BLE tracking as our phones can act as a BLE Beacon with a fixed UUID but random MAC address
Motion sensor: using the AM312 PIR sensor, we know if there is movement
Illuminance sensor: using a photoresistor we know how bright it is in the room
All this would be powered by means of an ESP32-POE. Since I renovated my house, I made sure an ethernet cable exited in the middle of each room’s ceiling, so these multisensors will be powered.
I already did a test with the MQ-135 sensor and some smoke and you can definitely see the value going out of the roof. I feel less confident about the MQ-7 sensor as it has ‘special’ cycle:
- Heat heater with 5V for 60 seconds
- Heat at 1.4V for 90 seconds
- Read the sensor near the end of the 90 seconds
I’m also a bit unsure on how to wire all these things together as both the MQ-135 and the MQ-7 sensor will pull (I think) too much current. The end goal is to 3D print/lasercut a custom case for this sensor.
Is there anybody interested in building this together? I already have the easy part working