https://www.youtube.com/results?search_query=ryan+norberg
In this video, and basically any video of a RPG driver they are using what appears to be a wheel speed sensor mounted to the front spindle. I see wheel speed sensors online but they don’t quite look like that…could just be the bracket they are using to mount it.
Anyhow, is this a wheel speed sensor and more importantly what is the wheel speed info telling the team?
Thanks,
Yeah looks like a regular speed sensor to me. They responsd more accurately and linearly (is that a word) than GPS speed, giving greater detail.
Enjoyed the video from NCMP, it’s pretty rare that I sit down and watch an onboard for entertainment.
Nice share 
In this case it looks like they have Mychron 4 with ebox extension, with the speed sensor on the front wheel. You could get all the same data from GPS but the big difference is GPS is calculated from trajectory. So speed is pretty good, but yaw, g force etc are all calculated from the trajectory. Whereas with the ebox, they are measured, so you have a more accurate picture of how the kart is doing things, rather then just what its doing.
They measure on the front wheel so you don’t get data effected by brake lock ups or wheel spin.
I would imagine the information garnered from the speed sensor would require a lot of intense analyzation. Pretty sophisticated stuff.
Speed, acceleration, deceleration, in the turns and down the straight’s, could all be analyzed. Make any change you want and know, right away, if, and, or where, you made any improvements, or the opposite.
Speed sensor is good, but a good accurate g-sensor gives you much more information about how the karts handling. The speed sensor mostly gives you the result, whereas the g-sensor can give you the why. If you know what you are looking for you can see understeer, oversteer, snap oversteer (caused by understeer), the inside rear hopping amongst other things.
What info does it give you as compared to g-sum?
The GSum channel mathematically combines the lat-g and lon-g (measured by your G-sensor) channels so that you can see if you are reaching and maintaining the maximum level of grip effectively (the vector sum). From a G-map (or friction circle) you can tell from the angle of the lines what the kart is doing for example. From the Gsum chart you can see something happened (you lost grip), but not necessarily what happened to make you lose grip.
Thanks! 
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