Did anyone already try updating their mod to latest tire CPM?

A

avenger82

Registered
I'm referring to the simplification/issue in QSA tire model(contact patch model) described here:
https://www.studio-397.com/2017/12/6512/

It seems that mostly affects cars at combination of both high speed and load. It seems major change in contact patch model. Apparently is not as easy as setting CalcPointAccel=1.0 and re-compiling tires using tTool.
 
I did do some tests with high load (6000N), max tyre speed (220km/h) and 0.02m lateral distortion, CalcPointAccel was set to 1. Ttool didn't crash but I haven't compiled the tyre yet.
 
I have to upgrade the group-c tires (again because I have already made CPM tires months ago). I would have to try 8000N and 400 km/h
 
@dbaldi Please don't tease.:D If the test car can go 400kmh or faster, you would inspire video nonsense beyond your wildest dreams.:cool: For those who do not know, the Group C mod being typed about is nothing less than awesome. That was my emoji quota for the year.

On topic I am hoping they do not update the roadster if it changes anything at all about it's driving.
 
Well, none of the current group-c cars can reach 400 km/h but they can reach 385 and would be good to have a margin. However, those same tires can be used in another cars ;)
 
Group C would surely benefit from the new CPM. As stated in the blog:
"This also marks the first major change to the QSA model itself in the 5 years since its rF2’s inception"
The cars seem to have decent physics already, so I think it's best to be careful not to break something else by using point based acceleration. So I think it would be best for the modders, to contact someone from S397 who has knowledge about implementing newest CPM.
 
I would like to see examples. I mean a tire from a car that I can drive today and compare. It's time to get a hand on current examples, and not from two years ago. This is the most frustrating area about rf2. It's almost a waste of precious time to try to make a car or mod by one or two persons, you need a team to really develop a car and test it at any possible enviroment.
 
On Flat 6 last change log states:
"...updated physics with in particular the introduction of CPM tires"

and also in description:
" Integration of CPM tires (Slick & Rain, around 90°C usage temperature for Slicks) adapted from S397 reference tires"

This suggest they started using CPM tires(adapted from S397) , this doesn't necessarily mean they utilize the latest point based acceleration QSA model.
 
Some modders where able to get help from S-397 i.e. Enduracers Flat6 mod have this in changelog:
"...Integration of CPM tires (Slick & Rain, around 90°C usage temperature for Slicks) adapted from S397 reference tires."
Also simtek and Lasse Ougaard where able to collaborate with S-397.

But yeah I'm sure modders could use a detailed documentation with examples.
 
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Probably it will take less time for S-397 to release yet another CPM update, than providing documentation for modders applied to current iteration of CPM:)

Also, maybe it's stupid question, but wouldn't it be possible to just use tires from one of the latest S397 cars (provided they are close enough between cars and S397 can share them)? In other words, for instance a GT3 mod that uses old tires model could easily use tires from GT3 Pack DLC (these cars utilize the latest CPM tires with QSA fix). S397 could just provide reference tires for a few car classes (i.e. GT, formula, road cars) that could be shared. I know that's more or less the case for AC mods.
 
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S397 has posted that surprising to them, Similar cars do not react to the same tire equally. I think the new tire will require more testing for each vehicle than just a simple cut and paste. But I like the idea of a tire store. Where modders could get a GT3 tire or F1 tire that is competent without having to spend months sorting them out.
 
> S397 has posted that surprising to them

I'm not sure what post are you referring to(?).

> Similar cars do not react to the same tire equally

OK but, IRL it's often the case where tires are taken from different model(i.e. using Corvette C7 tires in C5) . The cars may behave/react differently, but that should be accurately reflected in a sim - physics engine output should be pretty much the same as IRL.
This reminded me of the following thread:
http://www.racedepartment.com/threads/the-physics-discussion-thread.127125/page-8
Essentially a guy was making C5 mod for AC(he also owned C5 IRL and had access to accurate real data for many Corvette flavours) , but was claiming that, he had to fudge input data (i.e. unrealistic camber) i.e.
"The car did not behave the way a C5 would with C7 wheel/tires until I massaged the car with out of normal range camber settings."

He also constantly argued and felt offended and in the end the mod was never released(from what I checked). It's a shame because it looked like it had potential to be one of the best third-party mods.
 
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davehenrie said:
S397 has posted that surprising to them, Similar cars do not react to the same tire equally. I think the new tire will require more testing for each vehicle than just a simple cut and paste. But I like the idea of a tire store. Where modders could get a GT3 tire or F1 tire that is competent without having to spend months sorting them out.
Click to expand...
that's a really good idea dave..
@Marcel Offermans

could this be a thing regarding tyres.
 
avenger82 said:
>
This reminded me of the following thread:
http://www.racedepartment.com/threads/the-physics-discussion-thread.127125/page-8
Essentially a guy was making C5 mod for AC(he also owned C5 IRL and had access to accurate real data for many Corvette flavours) , but was claiming that, he had to fudge input data (i.e. unrealistic camber) i.e.
"The car did not behave the way a C5 would with C7 wheel/tires until I massaged the car with out of normal range camber settings."

He also constantly argued and felt offended and in the end the mod was never released(from what I checked). It's a shame because it looked like it had potential to be one of the best third-party mods.
Click to expand...

If a sim could accurately calculate EVERYTHING about a car that governs it's behavior and performance, then most likely the guy would not have had to fudge his settings. But there is no sim, anywhere, that contains enough data to match real-world with sim-world. We can get close, but 'almost' always there is some fudge in everything. The trick is to limit how much and where.
 
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