This is the prototype of an electronic nose with a room fragrance diffuser:
It's supposed to be placed in my toilet. Using the BME680 (a sensor for temperature, humidity, air pressure, and gas – whatever "gas" means – it outputs a value in "ohms" that increases when you fart towards the sensor 🤓), I want to use the gas sensor to detect when, well, when the toilet is being used, and then briefly activate the fogger and fan.
The fogger is currently diffusing an apple crumble scented air freshener.😍
The LEDs are purely decorative and blink red when the fragrance fluid is empty.
I've also added two wires to the diffuser, which I use to measure the electrical resistance of the wick that goes into the diffuser and sits in the fragrance oil reservoir. This way, I know when the oil needs refilling.
As always, the whole system is fully integrated into my home automation (MQTT/s).
That's the WAF-friendly version.
Somehow, that was still too boring for me.
I've had this thing hanging in my toilet/shower for quite some time now; it's just an 8x8 RGB LED status indicator. The green bar, for example, represents the charge level of my solar battery (not today, the picture is older!):
With foresight, I installed a sound card with a speaker right away 😎 You can see it on the left side of the box; there are holes there – the speaker is behind them 🙂
And the thing under the box is a radar presence sensor, which reliably detects whether someone is in the room or not.
If the electronic nose detects "bowel movement in progress," I could theoretically play a sound through this box first (e.g., "Sniff. Sniff, sniff.... - Wow, dude, respect....!" - I can stream any MP3s to it eventually 😉) and then – depending on how high the gas sensor reading is – either spray fragrance immediately or only after the person has left the toilet 😃
Cool, right? 😎