A multi-sensor fire detection system combining smoke, temperature, and CO sensing with a GSM-based SMS alert pipeline and an automatic trigger output for suppression systems.
Single-sensor smoke detectors are prone to false alarms from cooking or steam, and give no useful information once they trigger. This project fuses three sensor types — smoke, temperature, and carbon monoxide — so an alert only fires when the combined signature genuinely looks like fire, not toast.
An Arduino-based controller polls all three sensors continuously, applying a simple weighted-confidence model before escalating. On confirmed detection it drives a local siren, sends an SMS to a pre-configured number via a GSM module, and can optionally close a relay to trigger an external suppression system.
Because false positives erode trust in any alarm system, extensive tuning went into the confidence thresholds — the goal was a system reliable enough to actually stay switched on, rather than getting disconnected after the third false alarm.
Smoke, temperature, and CO readings combine into a single confidence score before alarming.
Confirmed detections trigger an SMS to the property owner within seconds, no Wi-Fi needed.
Optional relay output can activate a sprinkler or gas suppression system automatically.
Weighted thresholds reduce nuisance trips from cooking smoke or steam.
Runs on mains with a battery failover, so it still works through a power cut.
Onboard EEPROM logs the last 20 alarm events with sensor readings and timestamps.
Press the test button to simulate a confirmed fire detection event and watch the alert pipeline animate end-to-end.
I take on consultancy and freelance electronics projects — from prototype to production.
Get in Touch →