I cant wait to see its dusk and afternoon version
That's right... but bear in mind that purely scientific modelling and then simulation has to be exact nearly to the empirical precision of survey (as I know simulations done that way have to use ie. the same data input as modelled car and give just the same results as those obtained from that car). But it doesnt have to cope with grid of 20+ cars running on every (average) PC logged in. Therefore, yes, for racing sim it is important to get the scientific results and crucial to simplify complex modelling.
edit: plu another colorful diagram - I still wonder how to interpret this
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btw. joke for physics geeks:
A man jumps on the bus and asks (bad luck a physician):
- I s this direction to railway station?
- yes it is.
- and how many bust stops?
- 3
- thank you.
After two bus stops he asks:
- so this would be the railway station bus stop?
- no, now you have 5 bus stops
- HOW COME?! YOU SAID IT WAS DIRECTION TO THE RAILWAY STATION!
- yes it is, but the heading opposite
First, I just wonder how come you compare and almost make equal feeding a pet that has to eat flesh (ppl do not - if you think it is wrong, you dont have to do it... but nevertheless everybody needs some nutrition) with pushing someone in front of the car... quite creepy. And sometmies it is hard to tell if it is because both things are so worthless or the opposite
ok, I just copied and pasted formula given by Racer for Fy
and combined it (F combined)
and I must say it looks quite similar to my previous one (Pacejka combined)
FYI - in the second one I separately diminished Fx as vector by Fy and zeroed when negative, and respectively done with Fy, then combined both as vector components.
In the "Pacejka combined?" I just used in vector sum (Fx-Fy)^2+(Fy-Fx)^2
and combined it (F combined)
and I must say it looks quite similar to my previous one (Pacejka combined)
FYI - in the second one I separately diminished Fx as vector by Fy and zeroed when negative, and respectively done with Fy, then combined both as vector components.
In the "Pacejka combined?" I just used in vector sum (Fx-Fy)^2+(Fy-Fx)^2
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Direction (and heading
) come from x and y components I would imagine that this is the best referrence apart the feeeling - to get some raw data from scietific surveys (they are open in univerities' libraries - I just checked here, in Poland, several papers on tires) for both slip angle and slip ratio changing.
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these look stunning! awesome!
Overcast also looks really great but I won't use it - I prefer bigger contrast when racing.
@superclear sky: you live under such sky and you know colors better but I would say that photos you showed are postcards... racedays not always have to be on clear days (but they are not happening on overcasts
)@blackwood: I think clouds could have bit more perspective
I dont get it - what is interesting in watching ie. cat eating?
This is the easier method, as proposed here (racer.nl):
I modified this method using not only the Fx maximum but also Fy maximum.
Second method is "magic Pacejka formula" which considers so many coefficients that you cant have reliable data without relevant empirical data. But, all the work to determine the equations to represent those data is made, now it is only getting coefficients right
thats why I wrote "awkward" - I know I should see grip ellipse but...
I assumed that if the F vector is vector sum of Fx and Fy then knowing Fx (for Fy0, slip angle = 0) and Fy (for Fy0, slip ratio = 0) I should obtain grip circle plane (saddle type of plane with maximum on part of ellipse from Fxmax to Fymax and steeping down to zero) by diminishing vector component by the other component, right? But I didnt.
I deliberately didnt use coefficient equations from Pacejka model - first, I just needed 2 characteristics, second - I didnt want to deal with problem of proper calculation there
As I see in that model measurements were made for Fx (for fy=0) and Fy (for fx=0). I couldnt get empirical data for both slip ratio and slip angle changing. Honestly, I posted for some hint what I pressumed wrong.
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and you provided more cons than pros. Thank you
Do you mean... new cars?
if there would be maximum dimensions of the chassis (so in case of missing car default can be used)...
maximum power (or better engine capacity with some proportion on weight and power)...
minimum mass...
on live tracks...
nice lol... but... seriously... creating completely new track in mod mode is such an effort that I don't think there would be much for validation - 1 a year? 2?
So IMO from those LOLs - there are some issues when not lol'ed.
1st one - great idea
2nd - not really
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But I think there is nothing wrong with data table when they are not changing dynamically on some coefficients - simply because it goes like that: you take empirical data, then create equations that represent those data (usually with reference to coefficients known from theory of given area) and then when you need them in some calculations you first calculate those coefficients, then use them in next equations. So... if it is more efficient to get raw data (or "raw data") from table and then use them in calculations... then why not?
I mentioned about diagrams with longitunal and lateral components in function of slip ratio and slip angle.
This is how I think they would look like - I zeroed negative values from vector difference, combined is vectro sum of these two... and they look awkward. Honestly I wonder if this really look like that? (this just EXAMPLE to visualize the planes - no real data)
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so probably soon... nobody cares but some fanbois
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Well, I dont know how LFS engine actually works - does it calculate equations on table of coefficients or does it make a table of "raw data" for given setup and then uses them in calculations (which I dont know to what extent applicable as coefficients are also dynamically changing (pressure, load and so on))?
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oh nows, this diagram shows in one half of the quarter Fx in function of SlipRatio and SlipAngle and in other half Fy in function of SA and SR. Frankly speaking there should be 2 such diagrams connected in result giving one plane with F combined, but in terms of simulations those 2 would be needed more. Those could be obtained... empirically?
I'll provide them later today
scientific surveys are quite open to whole engieneering community and all of the data are secretly kept by manufacturers. But I was referring not to the knowledge of the developers but to the commercial pressure..
[quote]
[quote]An attempt to model tires that fails in the simplest of situations, a stopped car on an inclined or banked section of track. It's a "backwards" approach that tries to model everything based on slip ratio and slip angles, and working it's way back to forces, as opposed to the other way around. It's OK if you're happy with an 80% to 85% solution, but a 90+% solution requires a different or a hybrid approach.[/QUOTE]
Well, I think it is only because natural approach to gathering data - slip angles and ratios are set, forces measured in result. As they are empirical data (or diagrams derived from empirical data not theoretical assumptions) you can always switch them as you alike.
As I reckon, x and y force components are measured separately. What is probably the unknown is the area when they are combined - both combined force and separate components (I attach a sketch to show that area - the plane shows force combined, a vector Fx+Fy, on the top-right wall you can see the force y vs. slip angle, the top-left wall is force x vs. slip ratio + these are not real data, just the sketch to imagine relations between vector components ).
Additionally tires characteristics are surveyed for different behaviour under different change dynamics (small slip angle/ratio changes vs. sharp changes) and there probably hysteresis is involved (characteristic when loosing grip is different than when regaining)
All in all, this would be long time till simulators purposed for online races would be precise in all that.
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Tyre Physics progress spinoff thread for physics geeks
I would explain it that smaller developmemnt team meant better physics quality with lower need of commercial simplystics for racers.
I would repeat myself here but I see why Scirocco was the trigger - I dont think many of ppl here had BF1, FBM, RAC or MRT available to compare data provided in settings with output data. Now with real and quite popular Scirocco they cant be told that the results differ in case of the same settings.
I still hope Scawen would be ambitious enough to redo the physics engine to obtain data comparable to the real ones.
Segmented tire model has some issues - adding any new ralations between them (ie. to model heat propagation) multiplies exponentially number of calculations... but this can be modelled using virtual layer (like "average tire temp" that intereferes with every segment). Another thing is as I remember problem with different tire characteristics going out of grip and regaining grip which combined with change in longitunal/latitudal slip components gets quite complex and really obtained.
http://www.racer.nl/reference/pacejka.htm
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meh, I prefer GoogleEarth to plan road trips flying over at 800m height
To make a reasonable discussion, first there should be people knowing the topic, and there are some who I will read with curiosity. Second, they should know anything but speculations on the current physics problems - else they just speculate
So what's left to discuss is when the new patch will be published.
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well, I derived my opinion from much more distinct suspension moves in nKP (try LFS on rumble strips or checkerbrick(?) - nearly no suspension moves while you can feel it big on wheel /rumble effect/ ). Therefore when I saw those nose-diving with normal settings I supposed that less suspension moves, bigger absorbing on tires is the way to set LFS cars for proper feel.
I got that my knowledge from my dad, retired university scientist specialized in suspensions and hydraulic transmissions, so I roughly know what surveys were and are taken. And simulated
I'm just an amateur
(thats why it took me 2 years to design and make that green one and I am still just about to run the engine 
)
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just curious, how come? Aren't mods free?
First thing I found out feeding LFS with service manual suspension settings, was that it nose-dived as hell and suspension travel looked much too big as with current model most of shock absorbing is taken by tires.
Therefore my idea of LFS' simulation is that relations between output and input data are not in fact correct but they are tweaked way around - to get roughly proper output data (for .raw files and forces). VWS made me quite sure that Scawen cannot leave it as it is because VWS is real and widely known car so it would be widely commented when real settings and simulated results would differ alot - which I gladly welcome due to better quality of the sim as I know from my sources, in fact, tires are the part that is not completely modelled theoretically - in case of rain pattern cuts they are surveyed empirically, not designed from theory. But all the rest is very precisely modelled and surveyed.
You should be making second level mods
tires types, suspension parts, engine types used then in mods Well, I think a sim should have really good tested physics environment of the cars, presets for modding with restricted settings range (tires, suspension parts, engines, transmission parts... and certain calculations - ie. ccm vs. engine mass -> weight balance because of course everybody would make the car with biggest engine, smallest weight or tyre grip vs. durability and so on, so some realtions should also be included).
They could be distributed with game updates. The mods could be downloaded like skins - they shouldnt be much bigger than settings files. If someone disables CMX download (which is couple times bigger I think) he would see just game default body of the type.
Therefore cars could be fabricated at two levels - presets for parts and cars themselves - trying to get best results in class.
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I got FE snow mod... I think there is FE desert mod... I think Kyoto could be quite good for desert mod
FGED GREDG RDFGDR GSFDG