[SOLVED] Difference between Stop and Go point

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solive31
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[SOLVED] Difference between Stop and Go point

Post by solive31 »

I'm creating my own track and I crated a Stop / Go trigger. However, when I checked result, there was a difference in the graph at Stop/Go point when they should be the same. See attached pictures. Can I fix that?

Thanks

Sandro
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hms
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Re: Difference between Stop and Go point

Post by hms »

I think that is down to the accuracy of the GPS in the iPhone and the way HLT calculates when you cross the Start/Stop trigger.
It is unlikey there will be a GPS fix as you cross the trigger, so iirc HLT calculates when you hit the trigger based on time of the fix before the trigger, time of the fix after the trigger and interpolates (read that as Harry does his magic!) to calculate where and when it was you crossed the trigger. WIth the Apple GPS at 1Hz, there is roughly a gap of 1 second between GPS fixes.
But I may be wrong, no doubt Harry will be along shortly to correct me!
h
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Harry
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Re: Difference between Stop and Go point

Post by Harry »

As the snapshot shows, there is something like a invisible start finishing line generated from the trigger (point). What you can see in addition is you had chosen a different line driving into that lap and leaving it into the next: you started the lap more on the track's outer, while you finished the lap on the inner side. Maybe you made another point, but from my side this looks just fine.

- Harry
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solive31
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Re: Difference between Stop and Go point

Post by solive31 »

Thanks Harry for enlighten me, I was looking one lap at time and I wasn´t comparing them. It was a raining day and took me some time to figure out the best line driving. I looked the last laps and it was better. I´m planning submit this track to certification. Tks again
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