Project CARS 2 General Discussion Thread - Out Now on PS4/XB1/PC

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IanBell
We are going to release a marketing video explaining the details of the new tyre system soon.

But here's a head's up on stuff that isn't secret.

In short it's generations beyond what anyone has shipped thus far. It's also the first fully dynamic node based tyre model in a commercial game. Nothing is baked. It simulates things like surface rubber being removed from the tyre based on the temperature, both external (surface) and internal (fed via the thickness of the rubber, the abrasive properties of the surface, the heat generated from that, the heat dissipated from the brake discs based on their proximity to the tyre, the amount of heat generated from a softer tyre pressure and compound compared to a harder tyre pressure) and that's just tyre wear...

Much of the below we've already published but it got little coverage so:

For the tyre carcass we measure and simulate how the elastic behaviour of the compound changes with speed, temperature, and pressure. How rolling resistance changes with speed, temperature and pressure. We measure sidewall buckling at low pressure and how that varies among Bias Ply, Radial, or Hybrid constructions. We include Gyroscopic Effects and Dynamic responses such as vibration, telescoping, and twisting live and all at 600 times per second as per the tread simulation.

For the tread simulation itself we utilise our finite difference simulation of the contact patch, with the tire tread “flowing” through the contact patch. The whole tread itself is discretized into elements much like the carcass, but the contact patch itself is a finite difference grid bringing:
Flash Heating, which is the change of temperature in the outermost rubber layer through the contact patch.
A Componentized grip model. Each component is affected differently by road surface conditions, wetness, and temperature;
Deformation – the rubber deforms in and around asperities, resisting sliding motion;
Adhesion – the rubber bonds to surface rubber and materials in a realistic manner;
Tack – the sticky tacky grip you can feel on your shoes when walking a rubbered in track, related to adhesion;
Tearing – the ripping of rubber from the tire;
Cut – grip from the geometry, edges, grooves, and siping of the tread, with particular effect in dirt and gravel;
Tread channel depth and water handling;
Discretized and temperature sensitive wear; Curing and; Temperature sensitive elastic properties.

The carcass and tread simulations are coupled such that there is no roughness or “stepping”, while still preserving the detail of both simulations. The contact patch size, shape, and pressure distribution is determined by the carcass simulation and is used by the tread simulation. The forces on the tire from the road surface are simulated in the tread simulation and transferred as external forces to the carcass simulation.

And then we have the heat transfer simulation which handles heat flow between brakes, wheel well, rim, carcass, and tread layers. How the heat transfers amongst tread elements, from tread elements to the road surface, and from the tread elements to the air are handled directly by the tread simulation (including advection and evaporation). The pressure of the tire is maintained by the carcass simulation via the ideal gas law.


But we're 'simcade' :)


Edit, nearly forgot. We've also written a new drivetrain, throttle and differential simulation model for pCARS2.
Click to expand...

Really interesting post i love the nerdy stuff.
Crazy amount of detail & more than i imagined was possible especially in a console, i would imagine it needing a supercomputer with all the dynamic track & weather as well. I was recently watching a you-tube video with temperature sensitive cameras aimed at car tyres driving around a track & was surprised how quickly temperatures changed on the surface.
I'm interested to know what was improved in the drive-train? didn't stand out as being an issue in the fist game & i would of thought a bit more simple to simulate than something like a tyre?
 
nrosko
Really interesting post i love the nerdy stuff.
Crazy amount of detail & more than i imagined was possible especially in a console, i would imagine it needing a supercomputer with all the dynamic track & weather as well. I was recently watching a you-tube video with temperature sensitive cameras aimed at car tyres driving around a track & was surprised how quickly temperatures changed on the surface.
I'm interested to know what was improved in the drive-train? didn't stand out as being an issue in the fist game & i would of thought a bit more simple to simulate than something like a tyre?
Click to expand...

From what I remember from the WMD days, this is at least a revamp of the all-wheel-drive systems.
 
TexasTyme214
From what I remember from the WMD days, this is at least a revamp of the all-wheel-drive systems.
Click to expand...

Ian already stated that there were significant changes in how the Differentials work, so it has smoothed out the transitions from power off to power on, etc. That seemed to be the main area of focus in regards to the drivetrain from what I recall reading.

EDIT: The end result being that it is much easier to maintain a drift/power slide, catch a slidign car, etc. Not that it has made it "easy", just easier to manage as the car is less likely to have the harsh transitions that the current physics model has.
 
F1Racer68
Ian already stated that there were significant changes in how the Differentials work, so it has smoothed out the transitions from power off to power on, etc. That seemed to be the main area of focus in regards to the drivetrain from what I recall reading.

EDIT: The end result being that it is much easier to maintain a drift/power slide, catch a slidign car, etc. Not that it has made it "easy", just easier to manage as the car is less likely to have the harsh transitions that the current physics model has.
Click to expand...

Right thanks that makes sense.
 
F1Racer68
Ian already stated that there were significant changes in how the Differentials work, so it has smoothed out the transitions from power off to power on, etc. That seemed to be the main area of focus in regards to the drivetrain from what I recall reading.
Click to expand...

Oh, I didn't know he stated this too. Currently, cars with AWD (see Audi and Rt-12) where power moves from front to back to regain traction use the hybrid stuff within the game to make it happen. Apparently it's a good approximation but this differential and drivetrain overhaul would make it better.
 
nrosko
Really interesting post i love the nerdy stuff.
Crazy amount of detail
Click to expand...
Wow, this changes everything for me and a lot of sim fans....It's not nice to even tease this and it not be so. I'm grabbing a first class ticket to board this hype train.

IanBell
We are going to release a marketing video explaining the details of the new tyre system soon.

But here's a head's up on stuff that isn't secret.

In short it's generations beyond what anyone has shipped thus far. It's also the first fully dynamic node based tyre model in a commercial game. Nothing is baked. It simulates things like surface rubber being removed from the tyre based on the temperature, both external (surface) and internal (fed via the thickness of the rubber, the abrasive properties of the surface, the heat generated from that, the heat dissipated from the brake discs based on their proximity to the tyre, the amount of heat generated from a softer tyre pressure and compound compared to a harder tyre pressure) and that's just tyre wear...

Much of the below we've already published but it got little coverage so:

For the tyre carcass we measure and simulate how the elastic behaviour of the compound changes with speed, temperature, and pressure. How rolling resistance changes with speed, temperature and pressure. We measure sidewall buckling at low pressure and how that varies among Bias Ply, Radial, or Hybrid constructions. We include Gyroscopic Effects and Dynamic responses such as vibration, telescoping, and twisting live and all at 600 times per second as per the tread simulation.

For the tread simulation itself we utilise our finite difference simulation of the contact patch, with the tire tread “flowing” through the contact patch. The whole tread itself is discretized into elements much like the carcass, but the contact patch itself is a finite difference grid bringing:
Flash Heating, which is the change of temperature in the outermost rubber layer through the contact patch.
A Componentized grip model. Each component is affected differently by road surface conditions, wetness, and temperature;
Deformation – the rubber deforms in and around asperities, resisting sliding motion;
Adhesion – the rubber bonds to surface rubber and materials in a realistic manner;
Tack – the sticky tacky grip you can feel on your shoes when walking a rubbered in track, related to adhesion;
Tearing – the ripping of rubber from the tire;
Cut – grip from the geometry, edges, grooves, and siping of the tread, with particular effect in dirt and gravel;
Tread channel depth and water handling;
Discretized and temperature sensitive wear; Curing and; Temperature sensitive elastic properties.

The carcass and tread simulations are coupled such that there is no roughness or “stepping”, while still preserving the detail of both simulations. The contact patch size, shape, and pressure distribution is determined by the carcass simulation and is used by the tread simulation. The forces on the tire from the road surface are simulated in the tread simulation and transferred as external forces to the carcass simulation.

And then we have the heat transfer simulation which handles heat flow between brakes, wheel well, rim, carcass, and tread layers. How the heat transfers amongst tread elements, from tread elements to the road surface, and from the tread elements to the air are handled directly by the tread simulation (including advection and evaporation). The pressure of the tire is maintained by the carcass simulation via the ideal gas law.


But we're 'simcade' :)


Edit, nearly forgot. We've also written a new drivetrain, throttle and differential simulation model for pCARS2.

My question at this point would be " Is this an already existing physics engine? Say from ISI?" In particular, is this a tweaked Pcars 1 using the ISI motor from rF1 or is this something else?
 
Proff Chaos
My question at this point would be " Is this an already existing physics engine? Say from ISI?" In particular, is this a tweaked Pcars 1 using the ISI motor from rF1 or is this something else?
Click to expand...

If the first wasn't based off the ISI model, why would there be a reason for PC2 to do so?
 
jake2013guy
If the first wasn't based off the ISI model, why would there be a reason for PC2 to do so?
Click to expand...
Oh, ok. So its been mentioned already that it is a tweaked version of the existing engine..Sorry, I didn't know.

I was just getting exited hoping SMS maybe was going to use the newer engine from rF2 or maybe something else all together...
EDit *excited
 
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IanBell
It's a completely new tyre model. There's not a line of any other engine's code in there :)
Click to expand...
Thx Mr. Bell, I've heard from a beta tester that he's really liking the feel of it, and hopefully it can stay this way! I'm a PC user so hopefully we can benefit from the stronger hardware. Look forward to this! Thanks for being a developer in this genre. (been playing since the GT Playstation1 days)
 
F1Racer68
Click to expand...

@ 3:24 Ben talks about a lot of work having been done on that 'gray zone', when you go over the limit and the car starts to lose grip and break away, but you should still be able to control it without ending up in an immediate spin.

That's something that's nicely implemented already for PCARS2, and it's one of the first things you notice when playing the game. In fast sweeper you can intentionally make the back end come out and play with the steering and throttle to slide all the way through the corner if you want, and it all feels very natural indeed. Does wonders for the fun factor being able to explore and use (abuse) said gray zone, which was something that is indeed lacking from most other sims, where you'll be facing the wrong way before you had a chance to respond.

I haven't booted up AC in a week now so that's saying something :).
 
F1Racer68
Check my post in the confirmed car list thread. Pretty certain that is the XJR9 and not the XJR12.

The downward curve of the exhaust pipe gives it away. The XJR12 had straight pipes.
Click to expand...
The pictures were pretty poor which is why I thought it was 1 tailpipe on the XJR-9.
 
Konan
...and again SMS succeeded in spiking up the conversation...:cheers:
Click to expand...
Yes they did. Because this image.
RM-Amelia-Island-Preview-1988-Jaguar-XJR-9-14.jpg


2000th thread post.
 
Will we be able to set power restrictions for a race by adjusting the engine spacers? Like say I want the power levels for a race to be between 700-800hp...
 
Dsavage27
Will we be able to set power restrictions for a race by adjusting the engine spacers? Like say I want the power levels for a race to be between 700-800hp...
Click to expand...

I think this was meant to be passive in PCars 1. Engine life decreased significantly as you turn up the power. You'd have to enter the pits to get the car repaired. Now, SMS would have to increase the amount of time it took to fix the engine to ensure people aren't timing the engine life to the fuel stint length, nullifying the draw back. I think PCARS 2 will go the same route since Group C seemed to allow as much power as you wanted as long as you didn't use too much fuel or damaged the engine.
 
I wonder what the new circuits will be? In PCARS 1 there's 37 locations with 105 track layouts, 93 if you exclude the reverse kart layouts and the stages (Azure Coast Stage 1 etc). 39 locations if you count the classic tracks as separate locations.

We know Fuji is one, I wonder what the other possible 20 will be? I expect a few more tracks from the UK, so perhaps Knockhill?
 
bremics
I wonder what the new circuits will be? In PCARS 1 there's 37 locations with 105 track layouts, 93 if you exclude the reverse kart layouts and the stages (Azure Coast Stage 1 etc). 39 locations if you count the classic tracks as separate locations.

We know Fuji is one, I wonder what the other possible 20 will be? I expect a few more tracks from the UK, so perhaps Knockhill?
Click to expand...

Don't forget the various RallyCross tracks. Some may be real locations, some may be fictional.
 
bremics
Forgot about those lol.

Super hyped for this, need to use rFactor to get this many tracks and most of them are PS1 quality.
Click to expand...
Long beach, daytona speedway are also new tracks can't forget those. I'm hoping they also add sebring, Canadian tire motorsports park, belle isle, and barber motorsport park
 

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