Whereabouts Clock Simplified

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 Whereabouts Clock (v6)


When I published the last update to the Whereabouts Clock I knew that I would make another version that simplified the architecture.  Apple iOS supports the idea of location regions (home, work, etc.) and can notify an App when the user enters and exits a region.  This "presence" feature is utilized in Life360, OwnTracks, and others.

Instead of looking up a user's location from a static database, we can leverage the built-in feature to tell the Arduino clock how to move and when.  There's no more polling a web page for updates or maintaining a database of locations.

So how does the whole system work now?

  1. Devices with OwnTracks send location data (either standard location messages or transition events into/out of a known region) to the MQTT broker (Mosquitto).   These messages contain the region information setup on the device (more on that in a minute)
  2. The Mosquitto MQTT broker broadcasts these messages to its subscribers (other OwnTracks devices and the Arduino clock)
  3. The Arduino clock is also a MQTT subscriber and parses the messages from OwnTracks looking for region locations that match the name IDs on the clock.  Get a message that says a user arrived at "home"?  Instantly move the clock hand to "home".



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