Matt Romanowski

Anyone else working these into their analysis? I just tweaked my math channels to get what I wanted. There is a small error in them, but it's not something I can change easily right now.

Now I need to do some spreadsheet tweaking to make it easily usable across multiple data sets. I can't wait to get to some testing with and see how much of a difference this will make!

ProCoach

LuigiVampa

For those that did poorly in math can you explain what sensors you are using and how you obtain these calculations? I've been reading up on data acquisition but only so much is penetrating into my head.

stujelly

Is this all from the G load sensor and then using the g load rating of the tires??

Matt Romanowski

The grip factors are a way to filter out specific areas of the GSum plot to numbers on how much grip the car has under braking, accelerating, corning, from aero, and overall. It's a great tool to see how much tires fall off over a stint, quantify how a change affects handling, etc.

It's one of the things in Jorge Segers' book and covered in the seminar I put together a few weeks ago. His book is at

mark kibort

can you further explain the "grip factors".

this is per lap data , average to detect degradation?

why is braking grip factor less than traction gripfactor, and why does aero grip go to near zero on lap 16?

Just trying to wrap my head around what data you have put together and how to use it.

Matt Romanowski

The grip factor data is lap average. It takes the portion of the lateral and longitudinal G forces (through GSum) attributed to cornering, braking, traction (acceleration), aero, and overall total and quantifies it in those areas. It's not powerful on its own, but becomes very powerful when it is used to compare different setups, tires, drivers, etc.

My car has no aero, so the numbers for that will be off some. I didn't spend much time making sure it was giving good data there as I know we have no downforce being produced (we actually get some lift). The chart below shows a comparison between two different sets of tires. You can see the new tires produced higher numbers, showing they produced more overall grip.

If you don't have data, this sort of analysis isn't going to help you. The interesting part is this does not take anything more than an AiM Solo (or preferably a Solo DL) to gather the data!

mark kibort

no actually it sounds interesting. same track, car, but different driver (along with some video) you could really find some general information to help go faster, or help the other go faster.

So, it's a total summation of the forces of a lap in each direction? so each lap you are cornering longer /with more force, than braking , acceleration and (I don't quite understand downforce and grip terms ).

are you looking at each lap and seeing the trade offs..... so if you were loosing grip, you might see more acceleration and less braking and cornering forces toward the end of the session? and the mix of change can point to some reasons too?

LuigiVampa

This thread is convincing me that I will be hiring a data analyst as soon as I collect more data. Math was never my strong suit. Except for geometry and statistics. The only part of this data analysis I sort of understand is rooted in statistics.

Matt - I wish I could have gone to your course but I fear 98% of it would have flown right over my head! I need the dumbed down version.

333pg333

Interesting stuff Matt. The corner G's look a little low though. What car and rubber?

Caddell

Patrick, I believe the values in that graph are averages, not peaks. That will of course give lower values than we might be used to looking at. I love the idea of using averages (maybe weighted?) for this type of analysis.

Matt Romanowski

I think you would would really like the book. It's worth a lot more than the $100 they get for it. Plus, even with an AiM Solo you could do a lot of analysis on your driving and I bet you would learn a lot. The $400 buy in on a Solo is worth every penny. Let me know if you want one.

It's the average total G force for each specific area from a lap. Driving differences will change it (think one driver not driving as hard/fast as another). Think of it as grip available to brake, corner, accelerate, from aero (wing adjustments) and all of those together. It's most useful for defining the performance envelope of the car. Then, through measured changes, you can see how the performance envelope changes. Add wing - the aero component should increase. Tires heat cycling out - the traction, cornering, braking, and total should decrease. New tires - they should all increase. Is that a better explanation?


Don't worry about missing the seminar. It was a very high level seminar and was not for everyone. One of the interesting things that comes out of seminar like that, the more data you get and the deeper you dig, the more it comes back to basics. All the basics we talk about here (line, entry speed, apexes, exit speed, etc) are critical when you look at the differences in drivers and how to go the fastest.

Things like this Grip Analysis and some other things we learned are great, but if you can't drive repeatable laps, then none of it will help. You need good data to get good results (GIGO).

When you're ready, lets work together and I'm sure we can get you up and running with some great analysis. You would be surprised at how much you can learn from just G forces and speeds.

Matt Romanowski

Roger is correct. These are average values. You could do similar with the Max values very easily and many people do.

The car is a 914 on Nitto 225/45 R15 tires. The graph below is the min, avg, and max Lat G (GPS and slightly smoothed accelerometer) from the same session.

mark kibort

Yes, makes a lot of sense.

Keep us posted on a day where things change . interested to see the data. it would take the guess work out of those sessions where the time is slower and you don't know why!

333pg333

Ahh yes. Thanks Roger/Matt for pointing that out. Sometimes miss the details when reading these posts at work.

Having said that, then with the next graph showing Lat G Max over lap times there seems to be some much bigger peaks after about Lap 12. Nevertheless, for a car on that rubber you're seeing some impressive peak numbers. I realise that peak isn't the be all and end all and can sometimes be from skewed information, they're still high with that under consideration. Have you run the car on grippier rubber than the Nittos?

Assuming you're using the shock pots for the Aero reads but how do you correlate this to a G factor scale?