Physics thread

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Johnnypenso
I know what weight transfer is obviously, but what is the "weight transfer effect" in AC and how is it different in Project Cars? Is there a slider for it in PCars?
Click to expand...

There will be called "Seat of Pants" or "SoP" for short, might get called something that is more easy to understand in the future though. Actually there are more than one as you can see here (kindly stolen from Timppaq's post):

ps. Keep in mind that the below is heavily WIP at the moment and subject to change to make the sliders more understandable with text on the right eventually explaining and guiding you for each slider.

2mi3kli.jpg




As far as what weight transfer in AC is? Ehm, obvious I reckon.
The thing is that with a car with soft suspension the car will obviously oscillate its weight when exiting a corner. Especially if you add in a high center of gravity. Which could lead to a loss of control in certain cases as your steering wheel gets pushed into a direction you don't want the front tyres to point to... while having full grip. Resulting in the effect steering you off of the track or maybe even taking you for a 180 or 360 spin.

In Project CARS it can simply be switched off. Just set the "SoP Scale" slider to 0.0. So if it is not desired by the player it can be turned off, or vica versa.
 
LogiForce
There will be called "Seat of Pants" or "SoP" for short, might get called something that is more easy to understand in the future though. Actually there are more than one as you can see here (kindly stolen from Timppaq's post):

ps. Keep in mind that the below is heavily WIP at the moment and subject to change to make the sliders more understandable with text on the right eventually explaining and guiding you for each slider.

As far as what weight transfer in AC is? Ehm, obvious I reckon.
The thing is that with a car with soft suspension the car will obviously oscillate its weight when exiting a corner. Especially if you add in a high center of gravity. Which could lead to a loss of control in certain cases as your steering wheel gets pushed into a direction you don't want the front tyres to point to... while having full grip. Resulting in the effect steering you off of the track or maybe even taking you for a 180 or 360 spin.

In Project CARS it can simply be switched off. Just set the "SoP Scale" slider to 0.0. So if it is not desired by the player it can be turned off, or vica versa.
Click to expand...
I think you misunderstood my question or I've misunderstood your answer:embarrassed:. I know what weight transfer is in the real world, how it works etc. I know how it's supposed to work in the game. What I don't understand is, what is the "weight transfer effect" in AC? We're talking about canned effects right and it sounds like, but I could be wrong, you are saying there is some kind of canned effect programmed into the steering that is related to weight transfer in Assetto Corsa, that has no slider, but there is a slider for it in PCars. What is this canned effect and what happens when it's turned on or off?
Keep in mind I'm just getting into PC/Sim racing:boggled:
 
Johnnypenso
I think you misunderstood my question or I've misunderstood your answer:embarrassed:. I know what weight transfer is in the real world, how it works etc. I know how it's supposed to work in the game. What I don't understand is, what is the "weight transfer effect" in AC? We're talking about canned effects right and it sounds like, but I could be wrong, you are saying there is some kind of canned effect programmed into the steering that is related to weight transfer in Assetto Corsa, that has no slider, but there is a slider for it in PCars. What is this canned effect and what happens when it's turned on or off?
Keep in mind I'm just getting into PC/Sim racing:boggled:
Click to expand...

It is not just for 'AC'. Heck GT5 and GT6 prior to the 1.2 update was fully weight transfer based FFB.

Weight Transfer Effect is the effect of giving a counter steering effect based on how the weight of the car shifts.
So if you go through a left hand corner you will steer your steering wheel to the left, obviously. The weight will shift to the right side of the car, which will than produce a counter force on the wheel. Meaning the FFB motor will want to rotate your steeringwheel to the right, while you steer towards the left.

So it is a counter rotating effect.

Which is fine to 'add weight' to a low torque FFB wheel, but when you have a high torque wheel and go through some quick corner sequences (first chicane at Imola after start/finish for example) you will quickly loose sense of where grip is. As a result might lose control over the wheel due to the quick shift in weight, and thus the quick change of direction of the steering wheel.

So what happens is when you turn off all the canned effects, and let us asume that the above effect was the only one on. Than the steering wheel will feel and react, if the forces come directly from the car geometry/tyre model/etc..., just like in the real car (assuming the laws of Physics are correct). It will only, most likely, be weaker/slower/rougher than the real thing depending on your FFB wheel strength.
 
LogiForce
There will be called "Seat of Pants" or "SoP" for short, might get called something that is more easy to understand in the future though. Actually there are more than one as you can see here (kindly stolen from Timppaq's post):

ps. Keep in mind that the below is heavily WIP at the moment and subject to change to make the sliders more understandable with text on the right eventually explaining and guiding you for each slider.

2mi3kli.jpg




As far as what weight transfer in AC is? Ehm, obvious I reckon.
The thing is that with a car with soft suspension the car will obviously oscillate its weight when exiting a corner. Especially if you add in a high center of gravity. Which could lead to a loss of control in certain cases as your steering wheel gets pushed into a direction you don't want the front tyres to point to... while having full grip. Resulting in the effect steering you off of the track or maybe even taking you for a 180 or 360 spin.

In Project CARS it can simply be switched off. Just set the "SoP Scale" slider to 0.0. So if it is not desired by the player it can be turned off, or vica versa.
Click to expand...

I don't mean to disrupt the discussion here, but just wanted to add quickly: Forza should get the oscillation right. GT does it somewhat better, but suspension feedback REALLY makes the difference between just a sim and a deep/engaging one. PCARS will probably excel in this area, as have several other PC sims.

Would be interesting to see console sims/games attack suspension physics the way PC sim do.

O-kayy then, rant over. :D
 
Speedster911
I don't mean to disrupt the discussion here, but just wanted to add quickly: Forza should get the oscillation right. GT does it somewhat better, but suspension feedback REALLY makes the difference between just a sim and a deep/engaging one. PCARS will probably excel in this area, as have several other PC sims.

Would be interesting to see console sims/games attack suspension physics the way PC sim do.

O-kayy then, rant over. :D
Click to expand...

Oscillation should NOT happen at all!
There is no oscillation in my car's steering wheel either, so why should this happen? A steering wheel always relates to where the front tyres are pointing in relation to the car.
This is why in real life you can just let the car rotate around the front wheels when initiating a drift and grab the wheel once you have reached the desired angle of attack.
As you grab the wheel you than transition from having the back end pivot around the front wheels to a state where you force the rear to follow the front wheels even though it wants to oversteer and spin around the front wheels. The inertia and locking the front wheels (by grabbing the wheel and holding it in position) will keep the car in a sort understeering state as the car wants to flow to the outside of the corner.
Than at exit you roll the steering wheel back to center, and if the car's rear oscillates at exit it doesn't mean the steering wheel oscillates (in a FFB way) but will just gentle rock back and forth a bit at most.

So what I wanted to say is that no matter how fast a steering wheel moves, and thus the front wheels, it is always a smooth action and not an oscillating affair.

Just look at how smooth the wheel moves here in Chris Harris his drift lesson.

 
LogiForce
Oscillation should NOT happen at all!
There is no oscillation in my car's steering wheel either, so why should this happen? A steering wheel always relates to where the front tyres are pointing in relation to the car.
This is why in real life you can just let the car rotate around the front wheels when initiating a drift and grab the wheel once you have reached the desired angle of attack.
As you grab the wheel you than transition from having the back end pivot around the front wheels to a state where you force the rear to follow the front wheels even though it wants to oversteer and spin around the front wheels. The inertia and locking the front wheels (by grabbing the wheel and holding it in position) will keep the car in a sort understeering state as the car wants to flow to the outside of the corner.
Than at exit you roll the steering wheel back to center, and if the car's rear oscillates at exit it doesn't mean the steering wheel oscillates (in a FFB way) but will just gentle rock back and forth a bit at most.

So what I wanted to say is that no matter how fast a steering wheel moves, and thus the front wheels, it is always a smooth action and not an oscillating affair.

Just look at how smooth the wheel moves here in Chris Harris his drift lesson.

Click to expand...


AH! I thought you were referring to the suspension/shock absorber oscillation of cars depicted in the game!

:D
 
GranTurismo guy
Loads of talk on ffb, but none on actual physics :(
Click to expand...
Tons of good info on physics in the first few pages of this thread in case you missed it, especially from @LogiForce:

Here
Here
Here
Here
Here
Here
...and many more after that. It was those series of posts that really piqued my interest in the game.
 
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Random question: how well do you guys think the fantasy cars in GT like the Red Bull X1s and the VGT cars would translate into the Project CARS physics engine?
 
GranTurismo guy
I've heard a lot of people say AC is more realistic than PCARS, but only once vice versa
Click to expand...

If you want here I am to say the vice versa ;)

i don't really think any of us can judge wich title is better because we did never drive most of the cars, but i have to say that the tyre model of pCars is much more "lively" than AC one, that on some cars (mostly gt3 and formula cars) to me feels almost like "dampened" meaning that i can easily tell what the car's doing but to find the limit you have to mostly guess (or remember) when the grip will suddently be gone and the car will start sliding. In pCars i think they've nailed much better the on-limit feel with the grip going on/off reacting to your imput, and during on-throttle oversteer you can even feel the rear tyres bounching while they try to grip. I think AC is just more refined about having correct corner g-forces for each car, well tuned FFB and mostly finalized tyre model, but still feels somehow "old-gen", pCars feels already better to me, but regardless of the opinion i think i can say that it's tyre model is much more advanced (for example no low-speed related problems that AC still has, no lookup tables but everything is dinamic, drifts feel is a lot more organic since flash surface temperature introduction), so it's just about finding the right parameters for the model, and i think some cars are already there
 
SMS and Kunos followed a different development methodology. Kunos released a little at a time, fine-tuning as they went, SMS had released much more content then started working on fine-turning. In my opinion, the AC content (less of it) is more consistent but the good in pCARS is very good. They have a somewhat different feel, a different way of simulating but some will come down to preference and the equipment used. Somethings may feel more realistic in AC, others in pCARS. Take clutch use or very slow rolling inertia, more realistic in pCARS. In AC you stop on a hill and the car won't roll in neutral or clutch disengaged. In AC the simulation of weight shift seems very well done. But I'm not an expert.
AC is at 1.0, pCARS is 3 months away and every build has massive changes - most in the forward direction, some a step back.
 
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I thought I'd ask this question here, rather than start a new thread for a quick question (If I don't mumble-on)

I haven't been paying attention to every last bit of info for P.CARS (trying to avoid what happened with GT6-hype), but I'm curious if P.CARS will be simulating things like the McLaren P1's Hybrid system ?. AC apparently simulates the LaFerrari's Hybrid system, as EmptyBox mentions below, between the 6:00-6:15 time range.


​

The new technology in these "hyper cars" is part of what I find so alluring about them, and I'd like to see that aspect of them simulated. While I'm here, are 'full' turbo-systems simulated as well ?, like AC does with the Lotus 98T ?.

These aren't make-or-break factors for me (I'll be upgrading from GT6, so its all 'WIN'), I'm just curious how deep the simulation goes, I know about the individual tire & suspension models, but nothing about the other 'systems' or 'aspects'.
 
hotak
They just released a 400 pages pdf with all ben collins and nic Hamilton feedback since SETA tire model introduction and the devs answers
http://www.virtualr.net/project-cars-driver-feedback-compilation-released
Plenty of info For everyone interested
Click to expand...

Tons of good reading in there, thanks for posting! Nice to see Ben Collins give a shout to an online friend of mine (Ryan Caines). But his comments on the behavior of the old formula cars are priceless. He actually called the 98T (as of Jan '13) forgiving. As for his real experience, "...having thrashed Fittipaldi's Lotus '72 around the Ascari circuit it dashed any conceptions i had about the older generation F1 cars being hard or horrible to drive."
 
I'm only a few pages in on most of this discussion but what I read most is the tire black magic. I think this is almost an impossible approach unless you get a tire manufacture on board. That plus each tire is made so different from one another. They only real way to get it prefect would be in an F1 like environment, where there are 6 tires, all manufactured to exactly the same specs. On top of that every team tries to get so much data just on the tires they would be the only way to get a solid "physics" model from the tires.
Just my .02
 
DrJustice
^ The P1's hybrid system is simulated. I don't know what you mean by "'full' turbo-systems simulated", but turbos are simulated - run with a too high wastegate pressure and blow your engine. KERS and DRS are simulated. The IC engine simulation includes volumetric throttle.
Click to expand...

By 'full' I meant all the aspects of having a turbo system installed on a engine, such as waste-gate behavior. Your response answered all my questions, Thank-you ! 👍

Now to just save-up and wait-out the release. :scared:
 
wingman1659
I'm only a few pages in on most of this discussion but what I read most is the tire black magic. I think this is almost an impossible approach unless you get a tire manufacture on board. That plus each tire is made so different from one another. They only real way to get it prefect would be in an F1 like environment, where there are 6 tires, all manufactured to exactly the same specs. On top of that every team tries to get so much data just on the tires they would be the only way to get a solid "physics" model from the tires.
Just my .02
Click to expand...

I'm struggling to understand what you mean when you say F1 environment but also 6 tires at the same specs. Later in that PDF, you see the devs present a set of tires at a time for testing that have the same grip levels (or some times slightly different) to highlight which areas need improvement and which areas don't. Is that what you're referring to at that part?
 
Kurei
I thought I'd ask this question here, rather than start a new thread for a quick question (If I don't mumble-on)

I haven't been paying attention to every last bit of info for P.CARS (trying to avoid what happened with GT6-hype), but I'm curious if P.CARS will be simulating things like the McLaren P1's Hybrid system ?. AC apparently simulates the LaFerrari's Hybrid system, as EmptyBox mentions below, between the 6:00-6:15 time range.


​

The new technology in these "hyper cars" is part of what I find so alluring about them, and I'd like to see that aspect of them simulated. While I'm here, are 'full' turbo-systems simulated as well ?, like AC does with the Lotus 98T ?.

These aren't make-or-break factors for me (I'll be upgrading from GT6, so its all 'WIN'), I'm just curious how deep the simulation goes, I know about the individual tire & suspension models, but nothing about the other 'systems' or 'aspects'.
Click to expand...

Empty box is amazing. /random comment
 
From the official twitter account:

"Did you know? Project CARS' volumetric throttle system checks ambient track temp & air pressure to determine how much torque is available?"

"Did You Know? Project CARS' physics are calculated 600 times per second! And we check your finger movement over 250 times per second!"

Are all these super sim features for consoles too or PC only? Because this game at times sounds too good to be true especially for console gamers.
 
I think current gen consoles should be able to cope with this. PCs are not some outerworld super-alien tech. The bridge isn't as wide as some folks make it out to be.

I'm fairly sure PC and PS4 versions won't have major differences, performance and quality wise.
 

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