A faulty wire, a discarded burning cigarette, or a left-on curling iron can trigger sparks of fire to engulf everything nearby until all that’s left is brittle mounds of smoldering ash. Which is why smoke detectors are so important. They are life saving devices that can wake people up sleeping inside, well before the silent, but deadly carbon monoxide starts to kick in. But what happens if no one is home, and the alarm begins to blare? The place burns down into the ground without the owners knowing.
So when [Martin] purchased a battery-powered smoke detector and rigged it up to notify him exactly when the piezo siren is activated, the evolution of the automatic fire alarm continued into the realm of wireless internet-connected things.
His home automation system (a Raspberry Pi running Node-Red) links to a Funky ATTiny84-based sensor and transmits the data wirelessly, redirecting the information to his phone. SMS messages can be sent, as well as emails and pushbullet notifications. Once the piezo siren starts to sing, the system alerts him that smoke has been detected and that he should check on it as soon as possible.
The electronics fit perfectly inside the case waiting for any smoky disturbance in the room to light up. And what makes this project even better, besides the life saving capabilities and the instant push notifications, is that it was hooked up for the cheap. No need to buy a brand-new, expensive Nest protect, when all it takes it a sensor or two and a Raspberry Pi to hack the fire alarm that already sits in the house.
This video coming up after the break shows how simple it is to make.
For more projects similar to this, check out this leaking water detector developed from an old smoke alarm, and this beefed-up fire detector with built in video, temperature, and internet connectivity. You might also like this very tiny gamma radiation detector that uses a very small photodiode and a miniature solar cell as well.