## GPS Distance Behavior

General Q&A specific to RaceCapture/Pro. For app related questions post in the RaceCapture App forum. also see the <a href="http://www.autosportlabs.net/RaceCapture">RaceCapture Information Page</a>

Moderators: JeffC, rdoherty, stieg, brentp

bigbcraig
Posts: 3
Joined: Sat Jun 27, 2015 10:30 pm
Location: Waterloo, IA, USA

### GPS Distance Behavior

Moving this from the Software forum, meant to post here in the first place.

Could someone describe the functionality / behavior of the Distance calculation?

Right now I'm running an RCP Mk2, firmware 2.8.3, for autocross. I'm triggering logging onto an SD card manually with the button on the device. No start/stop recognition, no lua scripting at all on the device.

I have several good data logs of driving around and 3 of autocross runs from this weekend; on all of them the Distance measurement is simply blank, all zeros.

With a quick search, I've heard some other mentions of the distance calculation and how it references / interacts with start/stop points on a track.

Is there a way to get the distance to log in my application, just starting from when I start logging? For analysis plotting variables by distance is more elegant to me than time.

Thanks.

JMcDonough
Posts: 70
Joined: Tue Mar 10, 2015 3:31 pm
Location: Detroit, MI
You're not alone in having no distance in your logs. Brent and Co. are working on this for the next firmware release (2.8.4, iirc).

In the mean time, my work around has been to create my own distance channel in excel prior to importing the csv file into Dlog99 for conversion to .stf

I'm just using simple time based integration for mine. d(i+1) = d(i) + v(i+1)*dt with unit conversion correction factors as needed.

I create a channel (column) with distance in miles and one in km. You can configure GEMS to use either. One cool feature of GEMS is that if you trim the .stf file to just the time or distance period you want, it will reset the initial distance of the new trimmed file to zero. I've been manually starting the RCP, so it's nice to be able to start it back in grid and still have trimmed files that align correctly distance wise.
Josh