MoTeC Global Forum

Hi All,

I seem to have a weird problem with the track map in i2. If I look at a specific lap, there is a gap before the start/finish line so the track map appears out of sync with the data.

But looking at my GPS stats, everything looks pretty good (# Sats, HDOP), the weird thing is, the start of lap and end of lap GPS Long/Lat coordinates are the same. So it seems isolated to only the track map displaying the wrong position..? It is very clear when you also look at speed being 150km/h through T11/12.

This is specific to Sandown, I haven't run anywhere else yet.

Can anyone explain this?




Cheers!

The track map doesn't use GPS Coordinates to show the vehicle position, it uses the beacon point and a calculated "corrected distance".

There are two things to check:

1. The track map has been generated correctly.
In i2, go to Tools>Track Editor>Generate Track. Select an appropriate lap (ie not an in/out lap) and click OK.

2. Corrected Distance is calculated correctly
Add the "Corr Dist" channel to a T/D graph and make sure it continually increments any time there is vehicle speed (it doesn't reset on laps). If it doesn't do that, go to Tools>Corrected Speed and Distance. Make sure that your speed channel (Wheel Speeds/Vehicle Speed/GPS Speed etc) is in the list and ticked on. One thing to remember, this is a 'priority list', so i2 will use Wheel Speed Front L/R if they are available before anything else. If they aren't logged it will use a channel from the list and if none of those are available it will then use GPS.

If you happened to have a faulty or incorrectly calibrated wheel speed sensor logged, i2 will still use it over GPS Speed as it has higher priority (it doesn't know it is faulty) and your distance calculation and therefore your position on the track map will be incorrect. You can just turn off the channels you don't want used for the calculation.

Ahhhh that makes sense. Just needed to generate the track and that fixed it.

Checked the corrected distance to be sure, and that looks all good.

Thanks!