Released Caterham Academy

[Hebree]

Setup notes from 2013 for the academy, might be a little out of date but this explains what caster does for the car
Caster
Description
Caster is the angle around which the front tyres pivot when being turned. (The front wheel of a bike has lots of caster).

Adjustment
Front caster is adjusted using the lower wishbone, by using washers to push the attachment points forward or backward. Factory set is even with two washers either side of the attachment points. It can be moved forward or backward where all 4 washers are one side of the attachment points.
Rear caster is not relevant as the tyres do not turn.

Benefit
When the wheel turns, the caster adds additional camber. It is a way of getting more camber at the front of the car without breaking regulations. Most race engineers will want to set large amounts of caster.

Drawback
The trade off is heavy steering, making it harder to finesse the car and the car is less sensitive at turn-in. Driving style will determine whether these drawbacks are costing more time the the additional camber offers in grip.

 

[davehenrie]

Setup notes from 2013 for the academy, might be a little out of date but this explains what caster does for the car
Caster
Description
Caster is the angle around which the front tyres pivot when being turned. (The front wheel of a bike has lots of caster).

Adjustment
Front caster is adjusted using the lower wishbone, by using washers to push the attachment points forward or backward. Factory set is even with two washers either side of the attachment points. It can be moved forward or backward where all 4 washers are one side of the attachment points.
Rear caster is not relevant as the tyres do not turn.

Benefit
When the wheel turns, the caster adds additional camber. It is a way of getting more camber at the front of the car without breaking regulations. Most race engineers will want to set large amounts of caster.

Drawback
The trade off is heavy steering, making it harder to finesse the car and the car is less sensitive at turn-in. Driving style will determine whether these drawbacks are costing more time the the additional camber offers in grip.

If only rF2 had these...these..washer thingies!

 

[green serpent]

Can someone shed some light on something I've been mulling over lately (and apologies if we are going too far down the ffb rabbit hole).

With a DD when you are stationary on a flat surface, if you move the steering slightly left and right the steering springs back to centre. I interpret this as the tyres flexing but the contact patch more or less remaining in place. If you turn past a certain point and let go of the wheel (while stationary), the wheel will stay turned. I interpret this as the actual contact patch itself having moved to a new position.

So, assuming the above is correct, the force being felt through the wheel doesn't seem high enough if I imagine the friction of the contract patch grinding on the road surface. Even at slow speed I think it should be heavier.
Is there simply just not enough friction at the tyre level, or there is enough, and the ffb of the device itself just isn't strong enough.

Because I feel like if you sat there in the pits and adjusted the ffb to feel like a real car, that probably wouldn't scale up very well while driving especially with a weaker wheel.

I guess, are the low speed/stationary forces "correct" in rF2, or is it something that shouldn't be worried about because the correct ffb force only comes in at a certain speed?

Would there be any reason not to look at the NM in the steering column in the actual physics, then try to match that with the ffb (assuming your wheel is good enough).

I mention the stationary test because I feel like it's an easy repeatable test without too many variables. Is it possible to see how many NM the physics of the virtual car is generated, then try to match out ffb with this value?
(Apologies for the poor explanation here, it's difficult to word these things!)

 

[Lazza]

@green serpent check this line in your controller.json (or preferred custom profile)

"Steering torque zero-speed mult":0.3,
"Steering torque zero-speed mult#":"Multiplier at zero speed to reduce unwanted oscillation from strong static aligning torque",


@green serpent and just to answer generally the physics vs actual wheel force thing - with a DD, if you tell the game it can do 20Nm, and the car you're in says it maxes out at <20Nm, the game will send forces to the wheel aiming to give you the direct result of the calculations. If physics says the torque is 10Nm, the game will tell your wheel to do 50% (half of 20 = 10).

This 'how much does the car do' is set by the maker of the car (mod), so that can vary a bit (hence the ideal FFB mult to minimise clipping but maximise forces (for weaker wheels) can vary between cars. But hopefully with a powerful DD wheel most/all cars are set close enough that this scaling can occur.

Anytime the car is 'stronger' than your wheel, the game feeds your wheel the percentage of whatever the car is generating (if the car says 30Nm, and it's doing 15Nm right now, your wheel will get 50% - 10Nm output for this example).

Hope that explains more than it confuses...

 

[green serpent]

@green serpent check this line in your controller.json (or preferred custom profile)

"Steering torque zero-speed mult":0.3,

Assuming oscillations are of no concern, what should this value be set at for the most realistic force?

Thanks, I think I get it, I will read it a couple of times. But basically, if you have a very good/strong wheel, it is pretty much possible to set it up as 1:1 with the actual car physics.

 

[Lazza]

Assuming oscillations are of no concern, what should this value be set at for the most realistic force?

1.0 will use the actual forces (as much as is possible). By default it's reduced ( < 1.0) so it's not so hard to turn

 

[juanchioooo]

a stopped steering wheel never returns to the center, except those that use the Citroen system. the other way to return to the center is because you enable it in the steering wheel profile in the steering wheel application. I don't remember right now if the game allowed to configure that too, in reality it does not come back except for the Citroen system, Diravix I think it was called, but I don't know if that is how it is written

 

[Lazza]

a stopped steering wheel never returns to the center, except those that use the Citroen system. the other way to return to the center is because you enable it in the steering wheel profile in the steering wheel application. I don't remember right now if the game allowed to configure that too, in reality it does not come back except for the Citroen system, Diravix I think it was called, but I don't know if that is how it is written

I think green (? serpent? gs?) is talking about when you don't turn the wheel that far, and it comes back to where it started. When you turn the wheel far enough to actually move the tyres on the ground, it won't come all the way back anymore. Jump in your real car (with the engine off if you have power steering) and give it a go

(note: won't work so well on gravel!)

 

[juanchioooo]

I think green (? serpent? gs?) is talking about when you don't turn the wheel that far, and it comes back to where it started. When you turn the wheel far enough to actually move the tyres on the ground, it won't come all the way back anymore. Jump in your real car (with the engine off if you have power steering) and give it a go

(note: won't work so well on gravel!)

the car stopped, if you turn the direction to one side 350 °, the steering wheel will never return, neither off, nor with the engine running, at most it will release 1 ° due to the torsion of the tire, more than verified, except those with a motor recoil, which as I say used Citroen, I don't know if today there are more vehicles that use it?

 

[juanchioooo]

I worked with them for a while and at that time the Citroen CX25 or the XM had it installed from the factory.

 

[Lazza]

the car stopped, if you turn the direction to one side 350 °, the steering wheel will never return, neither off, nor with the engine running, at most it will release 1 ° due to the torsion of the tire, more than verified, except those with a motor recoil, which as I say used Citroen, I don't know if today there are more vehicles that use it?

You're really missing the point here.

You can turn the wheel a good 20-30° and it'll bounce back - I literally just went and did it in my Corolla (on concrete). Once I got past about 40° the wheel noticeably didn't return to centre (maybe 10° to one side). That's what's being talked about.

If you think a normal car (normal lock to lock range, 'normal' tyres) will retain down to a couple of degrees of what you put into the wheel, at rest, you need to spend more time playing in cars

You can't tell me I'm wrong! I just did it!

 

[juanchioooo]

You're really missing the point here.

You can turn the wheel a good 20-30° and it'll bounce back - I literally just went and did it in my Corolla (on concrete). Once I got past about 40° the wheel noticeably didn't return to centre (maybe 10° to one side). That's what's being talked about.

If you think a normal car (normal lock to lock range, 'normal' tyres) will retain down to a couple of degrees of what you put into the wheel, at rest, you need to spend more time playing in cars

You can't tell me I'm wrong! I just did it!

I think we are talking about different things, if you move a few degrees, the tire inflation plus the fall presses the rubber against the ground, and the inflation pressure, plus the fall and convergence, plus the natural shape of the tire, which is turned with metal and rubber, they make the pressure against the ground move a few degrees back... I think I misunderstood it must be the language, but very few degrees, only until the tire stops having pressure against the ground, yes does with the wheels in the air, a hydraulic jack will not return anything

pd.-and now I'm going to try the new content, which last night at the end, arrived very late

 

[mantasisg]

@dylbie I have had three cars including current one, first two I have some brief occasions to drive without powersteering. Not on racing speeds though. I don't see how one could do proper driving performance at such heavy steering forces, there is a reason that in old days they would use everything to make steering lighter - positive camber, low casters, other various leverages and inclinations, large diameter steering wheels, large steering ratios, tires also were different... I am not dismissing people wanting more steering force for sake of realism, but if anything they make them drive worse and then they also complain about car being difficult thinking that it is because something related to FFB lightness, they have no clue. And I also can't fully understand why they just don't make Caterham FFB heavier by changing maxnominalsteeringtorque, my speculation is that they are avoiding mercedes gt3 FFB fuss, because expanding scale of forces will make steering feel relatively lighter at understeering, especially with lower caster. I also don't get the steering ratio option in setup which is for limiting car wheels lock, instead for steering wheel ratio.

Cars I have been working on I had success making steering very close to what I wished or thought would be correct. We had some conversations in the past, dylbie, I shared some ideas... There isn't such thing as only steering feel it is a loop of whole cars dynamics that forms certain perception of car control of which moving steering wheel is major component. I am not new at modding, I know that it is impossible to please everyone when making something above average, at average everybody is like meh its fine, when something is very good, but has something unusual - then some loves it, and some hates it. For example Caterhams tendency to do neutral steering through turns just won't be understood by many simracers, especially the less skilled. Additionally with their ignorance first thing simracer will point at is going to be FFB, most simracers aren't too aware of vehicle dynamics, FFB is the only concept they are familiar with (and yet doesn't understand it too).

 

[mantasisg]

In my previous post i merely explained (rather poorly when i look at it now) how too high caster (usually together with too high negative camber) manifests it self.
in the video you posted he explains it briefly at 11:14. as the load on the inside tire increases, it has more traction (more support for the inertia of the car, like @green serpent said resisting the turn on the inside), this combined with the inside rear getting lighter, causes a sort of "whipping" effect of the rear weight to the outside (rear). more you have negative camber, more this effect intesifies (as the outside front dives lower). i dont know if im doing any better job at explaining this tbh..

But any case, this was obvious to me when i looked at people struggling on corner entries. as they got caught in the "whipping" effect when initiating the turn.
Obviously a lot is dependant of ones personal driving style, and to be honest, setup was not the only problem with those i saw struggling all the time..
But what is too much and what is too little?
I make a video tomorrow, i try to install the tiny pedal hud thingy, and put it next to the vehicle staus hud, so you can se my tire loads, steering and pedal inputs plus my ffb working. Then based on the car behaviour and hud(s) information, i want you to guess my caster setting
you will be surpriced, when i reveal it.

Yes I completely understand what you mean by whipping effect, it is sudden throw of rear weight towards outside. But I don't think it makes car resisting to turn, it is opposite it makes car eager to overturn, then combining to other factors rear end goes dancing, Caterham can be then nicely guided through turn at neutral steer or minor oversteer, which is nice, but I understand people with less skill just can't. Old 911 drove like that very boldly, it was controversial, today it is a legend. The way I understood the phrase "resisting to turn" was that it gives heavier steering. How could it resist to turn when it adds caster and equalizes front end loads and as you say whips weight at the rear towards outside, it does everything to combat understeer and add up to increasing oversteer tendency aka overturning. We must remember that we don't know exact amounts of weight moved by caster during steering, is it 10kg or is it 50kg differences ? It is important because issue could be less or more significant. Additionally to all that the softness of rear end is also important, softer rear end is going to react less dramatically and sustain better grip more equal wheel loads at least at turning in phase. One thing I tend to do with Caterham is that I usually decrease rear toes, it helps to have little bit more yaw angle with little less slip angle which helps to keep neutrality of a car. I drove it like that with min and max caster values, but obviously if max caster gives a bit stronger turn in, it also provides higher risk of oversteer, wait does it match that rule of thumb ? Ah, yes it does

Looking forward to your video, it is always interesting discussing vehicle dynamics with someone who knows what he is talking about. Please don't forget to isolate car loads change due to caster alone, by checking wheel loads by steering car while it is standing stationary.

 

[Lazza]

And I also can't fully understand why they just don't make Caterham FFB heavier by changing maxnominalsteeringtorque, my speculation is that they are avoiding mercedes gt3 FFB fuss, because expanding scale of forces will make steering feel relatively lighter at understeering, especially with lower caster.

I understand the scaling thing (excessive falloff), but quite a few people have DD wheels which will exceed the nominal torque range anyway (especially if lowered; and actually it's high which may not be helping perception as people will start to assume all cars should be <1.0 mult to reduce clipping, as evidenced by unthinking complaints when someone suggests to run the indycar above 1.0, so people now see the need/ability to turn it up higher as a fault) so adjusting that parameter won't have any effect for them.

From my limited testing I think the actual peak forces (steering column torque) with the 2 caterham versions aren't massively different. It's the lower forces that seem to be boosted, and I personally think it's related to the tyres - though I haven't played with the various parameters to know if that sort of change is feasible (or an actual construction change is necessary).

I also don't get the steering ratio option in setup which is for limiting car wheels lock, instead for steering wheel ratio.

Want me to check how many cars have been doing that since the new steering system was introduced 6 years ago? It's ok, I'm not serious. But that's how most cars are done with some (few) having actual varied ratio options. Stop being surprised by it.

 

[Bernat]

Additionally with their ignorance first thing simracer will point at is going to be FFB, most simracers aren't too aware of vehicle dynamics, FFB is the only concept they are familiar with (and yet doesn't understand it too).

Literally, some people just want strong FFB and don't care about anything else because they don't understand where FFB comes from. They think about FFB in terms of kerb effect, grass effect, oversteer effect, understeer effect,... with sliders to customize to their likings.

Devs could have added an option in the car customization screen to select the FFB level like some mods do.

 

[juanchioooo]

Well, tried the Caterham, for me I have never been in a real one, not even in a school or competition one, even less if there are many differences, I can say that inertia is cool and it's just a matter of getting used to it, control I think it's great, super fun, no complaints for me. congratulations studio 397
Except that when I focus the television camera, I would say that parts of the car disappear or even the headlights and fenders, sometimes even the pilot is seen as transparent, (eye from the external TV camera) that is, the retransmission of tv,... yes, as the car gets closer to where the tv camera is, all the parts are loaded...

I use a TSPC with the FBB at 100% at 450º
Smoothed to 12%
MST - 3%
in case someone wants to try my configuration
450º because my steering wheel is GT3

 

[juanchioooo]

AUTO DETAIL FPS before I had it deactivated, because when I activated parts of the car disappeared, but that option is no longer in the options or I can't find it

 

[Lazza]

AUTO DETAIL FPS before I had it deactivated, because when I activated parts of the car disappeared, but that option is no longer in the options or I can't find it

It's still there, but from a very quick look the car rims at least were invisible at a medium distance from trackside cams. So probably just the car.

*oops! Maybe it's gone! Well, that confirms the car then...

 

[Bernat]

I've tried the new version and it seems that with the higher caster I loose some detail in the FFB. It feels stronger overall because there's a higher centering force, but it seems to loose detail.

Setting caster to the minimum 3.5 and FFB mult to 150% to compensate for my weak wheel seems to offer the best results, pretty close to the first version I think.

I wish they've added the FFB strength setting in the custom car options instead.