How To Setup gSum In AiM Race Studio

Issue: You want to see a combined lateral and longitudinal acceleration trace to assess the drivers use of the grip.

Looks like:

AiM Race Studio gSum Channel
AiM Race Studio gSum Channel

Need to know:

  • gSum shows the drivers use of the available grip.
  • Read more about the “friction circle” theory its based on here.
  • Looking for smooth hills with steep sides.
  • AiM created the channel for you but it needs you to add it.
  • Uses AiM Math channel functions – the “set” you will need to save if you want to use again.

Method: Setup gSum In AiM Race Studio

  • Select Modify -> Math channels
AiM Race Studio gSum Setup
  • Select General (Top left)
AiM Race Studio gSum Select General
  • Click AiM_G_Sum and then Add >
AiM Race Studio gSum Click Add
  • Select your session data (Click top left)
AiM Race Studio gSum Click back to your session data
  • Click <<< Paste
AiM Race Studio gSum click paste
  • You now have the channel added to your data set. The next thing is to confirm it is working, configure and test it.
  • Click Test channel
AiM Race Studio click test channel
  • It is likely you’ll get an error:
AiM Race Studio channel error

What this means is that the software can’t find the highlighted part of the equation. In this case the software is looking for a channel called AccLat but it can’t find it.

AccLat is a channel for lateral acceleration. You need to replace this with the name for lateral acceleration in your data set. There are several options for this sometimes. If you are not sure choose GPS_LatAcc :

AiM Race Studio replace lateral acceleration channel
  • With AccLat highlighted, double click GPS_LatAcc
  • This will replace the text in the equation like this:
AiM Race Studio replace Long Acc too
  • It is likely that the longitudinal acceleration will also cause you an error. Replace in the same way as the LatAcc.
  • You should have something like the channel description below.
  • Press Test channel again and look for confirmation it is “correctly interpreted.”
AiM Race Studio Confirm Math Channel is working
  • The standard channel has minus scale. As this gSum channel is never minus, you can replace that so that it plots nicer in the Measures Graph.
  • Replace the -3 with 0 :
AiM Race Studio Maths channel replace with zero
  • Your channel should be created. Click ok.
  • To visualise this channel in the Measures Graph click on AiM_G_sum
AiM Race Studio visualis gSum


This is Today I Learned Motorsports is part of a growing collection. Snippets of things I am learning day to day and sharing with you so I don’t forget! Share if you like it. Click here for them all. Sign-up below to never miss the new ones?

Weekly motorsport insights that you can read in 5 minutes, for free. 

Forget vagueness. Get clarity on how to make you, and your car, faster on track.