Matt Romanowski

You have to have steering (or steered wheel) angle to determine over and understeer. Without that, you don't know what the input was, so there is no way to compare if it's more or less than expected/required.

Raeffer Govoni

Hi Greg

I am not very savvy at this but was wondering if you could give me some direction.

My 12 year old son races karts and his ability to provide feedback is rather limited. Having the telemetry yopu have produced above would be quite good for us to have. I have managed to build the calculatedSteer maths channel

((GPS_LatAcc*9.8*0.95)/(GPS_Speed*GPS_Speed))*57.2958

However I am unsure as to what to use for the actualSTEER channel. I dont have a steering sensor (one on the way) so I am using

GPS_Gyro*0.025

Is this correct?

Raeffer Govoni

"There are other ways to visualize understeer/oversteer by looking at the difference between GPS lateral Gs and system lateral Gs. In that case, you won't need a steering angle sensor."

Any ideas if you can acheive this on a mychron5 on a kart?

boxboxbox

technically you don't, if you have a yaw sensor.

yaw rate vs angular velocity is also another way to do u/s vs o/s; and in a way is probably more accurate than using the method involving the difference of WB/R vs steered angle. this has been covered in detail in several literature.

Racingjordi

[QUOTE=Frank 993 C4S;14390288]So I have been experimenting around with looking to visualize understeer/oversteer to independently confirm my butt feel. For this type of analysis I can highly recommend Graham Templeman's book "The Competion Car Data Logging Manual" which is available on iTunes.

Graham's theoretical steering angle formula with the correct units plus the wheelbase of my 2012 Cayman is:

7.969/ ((GPS_Speed*1.467)^2/(GPS_LatAcc*32.167))*57.2958

This allows you to calculate the THEORETICAL front wheel steering angle that you would achieve at very slow speeds.

Could you explain where those numbers represent and come from?