Tim Dawson (9/10/2015)
Stopping is defined as groundspeed being below a certainly threshold (around 10 knots) for a minimum period of time (at least 10 seconds). All values from memory. It works well and I don't think there is cause to revisit the algorithm at this point, even if it's not perfect.
Ah! That explains why I frequently get "broken" logs when doing aerobatics - I'd always assumed it was because I'd shielded the GPS antenna, but extended vertical manoeuvres would fool the algorithm. Could the "groundspeed zero" test be combined with a "within a few metres of the ground" to prevent false stops?
The other option is to start logging manually. If you do that, SkyDemon won't stop the log automatically.
That's also useful to know - I didn't realise that manual-start would prevent auto-stop. Thanks Tim!