This is my doorbell:

Ring me

Free, amuses the children, but unless you’re standing next to the door there’s not a chance of hearing it struck. Not terrifically functional, not pretty…it’s time to fix that. I could buy one, of course, but my boys were just presented with a littleBits® set by doting grandparents and I don’t have a project underway at the moment, so I’m going to build one instead. I’m going to build an Internet of Things doorbell. And then I’m going to use it to track authorized and, I’m betting, unauthorized ringing.

A traditional doorbell connects a human-operated button with a noise generator for notification purposes. Our IoT doorbell will connect that button with the Internet, and from there we’ll have all sorts of options for notification. It’s about as simple as an IoT implementation gets:

1. Place a sensor at the “edge” of the network
2. Arrange for it to transmit data to a cloud-enabled gateway
3. Forward data from that gateway to a designated point for processing
4. Make hay with the resulting data stream

Time passes…and there, it’s done (well, prototyped — still need to make a case to hold it all together):

An Internet of Things doorbell

Here it is in more detail:

1. The sensor is a button. It collects discontinuous event data: I have been pressed. It doesn’t tell us anything when it’s not being pressed. All it does is say “event happened!” (It also makes that LED light up so the person pressing gets feedback indicating that the sensor registered their input.)
2. Using the cloudBit part attached to that button we’re able to transmit those events to my home wifi network and from there to the littleBits cloud.
3. The cloud is where the functional logic resides. Using the IFTTT platform, I’ve created an alert: if you hear of an event, email me and, since it doesn’t cost any extra money and hardly any extra logic, message me via Twitter, too.
4. Each event will leave a trail of data behind it: on littleBits’ servers, on the IFTTT platform, on my smartphone, and, let’s not forget, on every intermediary computer between my kids’ fingers and my phone.

With a regular doorbell our story would end here: we’ve made it, we’ve installed it, long may it run. But with an IoT doorbell we get something else: a data stream that tells us how that doorbell is used. And from that we’re going to learn a whole lot more, about doorbells, and about the Internet of Things.

In a future installment we’ll look at how well this doorbell worked. Want to build your own in the meanwhile? Instructions are here.