I am particularly interested in status of tire model and also what tires are supposed to be on rtrainer or will be on sb2000 or wherever I can get a street tire. Please don't make this into another thread, just point me to the current thread as the one I found was closed in August. Just want to understand what we have now and stay up with developments...
Technically the latest is this one: http://isiforums.net/f/showthread.php/8660 Not really sure which is most up-to-date, sorry...
OK, then . A few questions. Sorry if redundant. Is rtrainer tire performing as expected regarding grip levels? Is tire model done? If not, are there aspects that are done, like grip, or is everything still on the table at the moment? In response to questions I have about lack of expected wheelspin on a model, I was told that rtrainer tire which I am using is not performing correctly as a street tire (too much grip) so just would like to know if this is true as if that is the case then it may make sense for me to put physics testing on hold. Many thanks in advance...
Tyre model is in no way finished that's all I know. I also heard parts of the tyre model sill weren't even active yet, let alone being finalized, something to do with the carcass and sidewalls or something, not sure. It's definitely not finished that's for sure.
It is not really street tire, it is tire that is grooved race tire, nearly impossible to cook and somewhat more grip than performance street tires. I would consider it as DOT legal track tire. Can't again remember what was exact brand of tire, but I think that Skip Barber website has same or similar tire name in their car specs which would help to research what tire it really is, even perhaps not exactly same tire it is same class tire. It has under 6mm tread, while most street tires have more, there were not many I could find to have so little tread, mostly track tires that can be used on street were such. So too much grip is perhaps not so much too much. However one interesting aspect about rTrainer tires is that TGM geometry sections are showing tire that is vastly different size than what rTrainer tires are and that is then scaled down by size multiplier. First value is width of tire, so ,ax is 0.195 meters, that is for HALF tire, multiply that by 2 to get total width of tire and you have 390mm wide tires. Then multiplier in realtime section of TGM file shrinks that to somewhat more believable value. So that alone tells me that tires are certainly not quite finished in rTrainer. Code: Geometry=(0.175,-0.182,0.006) Geometry=(0.18611111111111112,-0.202,0.006) Geometry=(0.1927777777777778,-0.222,0.006) Geometry=(0.195,-0.242,0.006) Geometry=(0.1927777777777778,-0.262,0.006) Geometry=(0.18611111111111112,-0.282,0.006) Geometry=(0.175,-0.302,0.007) Geometry=(0.16,-0.316,0.009) Geometry=(0.14,-0.322,0.011) Geometry=(0.12,-0.324,0.011) Geometry=(0.1,-0.324,0.011) Geometry=(0.08,-0.324,0.011) Geometry=(0.06,-0.324,0.011) Geometry=(0.04,-0.324,0.011) Geometry=(0.02,-0.324,0.011) Geometry=(0,-0.324,0.011) Last I know is that contact patch load distribution is still WIP and that is just one aspect that has or does not has (sounds odd, other words maybe?) possibility of affecting grip greatly. You could of course take tires from 60's F3, but I have found out that they do have also quite bit of grip. So, making tires yourself is next natural step http://isiforums.net/f/showthread.php/2796-The-tgm-and-ttool Again more in Wiki http://isiforums.net/f/showwiki.php?title=rF2+_+car+physics+_+useful+links+for+information Don't worry too much about geometry first, you don't probably need even to do tire tool calculations either. Focus solely to [Realtime] section in TGM first. Two BaseCoefficient at the top, they are base level of grip of tire. These define largely characteristics of tire, groove effects affects how much tire wear effects to grip GrooveEffects= This affects how temp affects grip StaticCurve= These effect how sliding affects grip SlidingAdhesionCurve= SlidingMicroDeformationCurve= SlidingMacroDeformationCurve= Format is something along lines of (condition, effect, condition, effect...) and so on, 1.0 effect is no change and there less is less grip, more is more grip. Of course there are scientific formulas and methods setting these, but haven't found much about that yet, so make backup from your tgm file and change them a bit, nothing too large, 0.1 is already 10% change. Materials of tire and geometry is then another story, but at first one can stick with materials that tire already has, even tire size can be changed with size multipliers, but at some point that is worth to change to proper size and do tire tool calculation, however most of the handling you can change from realtime section and no need to use tire tool for that.
Thanks, jtbo. @All So what I am taking away from this is that tire model is WIP so it may be best to postpone my physics testing. I am also taking away that rtrainer tire may not be good approximation of tire for vehicle I am modeling (see below). Lastly, since my head also exploded from jtbo's explanation , I believe I will most likely wait for a more similar tire to become available instead of modeling my own. @Tim My understanding is that there has been concern about effort around tires and with jtbo's help I am beginning to understand why. Is ISI planning to offer a variety of plug and play tires or otherwise support the community's need for pain-free tires or tire specialists ability to develop tires? I believe this is the tire on vehicle I am modeling... Dunlop SP Sport 2050 P225/40R18 Y-speed rated high-performance summer tire View attachment 4689
I remember Tim replying somewhere that there indeed would be plan to make many different tires available, but this can also be fairies inside my head drinking and singing instead of correct memory trace, so don't trust it too much. Hmm, I must refine my explanation of tires then, it is not really too difficult, well after you get hang of it, but what is difficult is to find ways to get accurate results out from tires, but I would recommend forgetting that goal first and starting with what every parameter affects to handling and grip, then as more information comes available, one has perhaps small hope of doing tires properly and when one knows what bit does what at that time, he certainly will find tires easy to make, compared to one that has only done things correct way and don't have that feel to adjusting tires. But those sport tires might be relatively easy to factor out from rTrainer tires, try to get 0.7g with 2000kg vehicle and there lies a challenges, so easily tires start to be like on ice when you lower the grip, but as you probably are fine with 1G or even bit more, there should be less change and easier to cope with that change then.
I believe I also read where Tim mentioned tires to be available to modders. Seems it was a discussion about "Dirt" tracks--not sure though--about the specific discussion.
I was told (very recently) a dirt tire would be included in the 'example tires' we give to modders, and that this would happen before we have done anything with dirt ourselves.
Hi Tim, Could you ask the DEVs on the current state of the tire model(other than being WIP)? Greets, Roland
