Building a home sensing network

Soon I move into a house that my wife and I have been renovating for ~ one year. Obviously as part of designing the house I've been building in a number of technology aspects, and now I want to design a series of sensors to deploy in the house to support home automation.

I'm going to write a series of articles about each of the parts I'm building. But I'm starting off with my requirements and a high level design in this one.


The house is not big, and it will have LAN cabling across most of the rooms, but I don't want to use this for sensor data. My requirements are:

  1. Can be powered by a standard USB power supply
  2. Connects via WiFi
  3. Can sense light levels, temperature, humidity and motion
  4. Can send IR signals to control devices with IR remotes
  5. Sends and receives data using MQTT
  6. Data processing happens on my local network and components can be deployed in containers running on an ARM machines
  7. Data changes can trigger actions
  8. New sensors can be added easily and can be remotely configured

High-level design

There are many aspects to building this both for the devices (electronics, code and enclosure) and the software side. I'll write an article for each bit. I'm starting with the remote sensors.

Here's the high-level design block diagram:

home sensors block diagram

My first article in the series will be about building the 5v to 3.3v power converter (and why I need to do that).

-- Richard, Jun 2020