The Blog of Ian Mercer.

Home Automation States

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One of the challenges of building a great home automation system that does the right thing all the time without you needing to tell it what to do is the problem of figuring out what state the house is in.

Some of the many possible states include:

  • Not occupied
  • Not occupied and the residents are out for the evening
  • Not occupied and the residents have gone on vacation
  • Occupied
  • Occupied but everyone is asleep
  • Occupied and there are dinner guests
  • Occupied and there is a party going on
  • Occupied and there are guests staying over

States might affect how long the heating stays on for, whether the driveway lights are left on or whether they go off once everyone is home.

In order to recognize the correct state a home automation system needs many different sensor inputs. My own home has over 200 sensors including door sensors, motion sensors, driveway sensors, under-floor strain-gauges and IR beams. It also uses WIFI-sniffing to detected the coming and going of mobile phones and other mobile devices that connect to WIFI.

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