The online racing simulator
Detailed description of the Physics model
Is it available anywhere?

If not, does anyone know if a controller's force feedback is used to simulate the tyre self aligning torque (both from castor and contact patch slip angle?)

TIA.

RK.
As far as I know, the force feedback simulates the forces acting on the (virtual) steering column. It is possible to feel changes in the setup (e.g. caster), just like it would be in reality. Try some different settings and you will feel the difference!
Please dont ask for detailed physics here. you wont get it, since there are competitor products and this is a public forum.

however from what i recall, selfaligning torque from contact patch slip angle is not modeled yet in the FF. Its in dev queue as basically anything thats missing is part of it.
I'm not looking for implementation details. I suspect that's probably classified information .

Just curious of what elements are actually simulated. Self torque from slip angle is one of the most informative for a driver, so I was expecting that to be included. However, I don't seem to feel anything on my controller... but maybe I'm thick

RK
Quote from KiDCoDEa :Please dont ask for detailed physics here. you wont get it, since there are competitor products and this is a public forum.

Well seen as Scawen generally tells us what new physics features hes putting in to the game i see no reason why we cant get detailed physics. Competitors are not going to get an advantage by finding out what LFS simulates.
seeing race koala, the original poster, understood what i said and even replied apropriatly , i fail to see why you would not understand what i said. but hey, have fun.
#7 - Woz
Quote from racingkoala :I'm not looking for implementation details. I suspect that's probably classified information .

Just curious of what elements are actually simulated. Self torque from slip angle is one of the most informative for a driver, so I was expecting that to be included. However, I don't seem to feel anything on my controller... but maybe I'm thick

RK

What do you mean exactly when you say "Self torque from slip angle". The FF in LFS is driven from the forces acting on the front wheels. So if the back end steps you will feel the front wheels try to track the direction of movement, or in a FWD if you get wheelspin you feel the steering get lighter etc.

As stated all the forces are driven from the front wheels which in turn get transmitted through the steering column.

Some cars have have far less feeling through the steering than others but this is all based on steering geometry and the effect this has on how the forces are transmitted.
Quote from Woz :
As stated all the forces are driven from the front wheels which in turn get transmitted through the steering column.

Some cars have have far less feeling through the steering than others but this is all based on steering geometry and the effect this has on how the forces are transmitted.

Thats exactly what hes talking about. Castor/camber/SAI/the whole enchilada effects the torques that the tires feed to the steering column. They are called "self-aligning" sometimes because they generally work in that manner.

There are some interesting exceptions. Brake moderately on a split surface with big negative scrub and the car will pull TOWARD the slippery half of the surface
I think he is actually referring the the third force that a tyre generates after lateral and longitudinal force. Ie a tyre which has slip angle generates a torque around its contact patch in addition to linear forces in the ground plane. This is generally referred to as self-aligning torque or aligning moment. I would be pretty suprised if it isnt modelled in the tyre model, as even straightforward Pacejka models in Racer and ISI models produce it.

Obviously, this force is a component of what you feel through the steering wheel (although actually a pretty small one, as cars with zero-scrub angle and low caster will prove).

The larger component of steering column torque is generated by the fact that the linear tyre forces are applied some distant away from the steering axis itself, so this creates a torque around the steering axis. And the larger the scrub radius and caster, the bigger the distance between the contact patch (where the forces are generated) and the steering axis's intersection with the ground.

Thinking about it, I'm not sure what the effect of aligning moment on the steering column is. Obviously a linear force applied a distance away from an axis results in torque on that axis, but surely a torque applied some distance away from an axis actually results in a linear force on that axis?
Which begs the question, do aligning moments in tyres even result in torque in the steering axis?

But just to return to the original question. FF definitely account for castor, inclination and scrub radius in its generation of FF forces. In S1 these values were independently variable (urealistically) and you could clearly feel the various effects. If you arent feeling anything at the moment, then its possible you've some kind of technical problem.
As for the effect of tyre aligning moments, then I'm not sure, but I dont think they have a large effect on force feedback.
I'd be inclined to say that even if this 'self-aligning torque' is yet another
force, it's still acting on a wheel and therefore mainly controlled by caster,
inclination and scrub radius, having all those to 0 would 'cancel' that
torque giving it no axis to spin around. Then again, once the contact patch
deforms, there is an offset big enough to make that torque turn the wheel
around the steering axis.

There must be a way to have some initial caster/inclination/scrub so that
offset becomes null as the contact patch deforms. I'm not sure what the
use would be as this would mean you'd lose steering feel as the tires
approach their maximum deformation, in other words, you'd lose feeling right
before losing grip. In a way, this is a bit like winter driving where as soon as
the steering feel 'light', it means you are sliding.

What i remember from using a FF wheel in LFS is that scrub changes would
be very noticeable in the FF strenght/resisitance and that cars generally
steered into a slide like real life (it 'auto-counter-steers', although i suppose
this is mainly because of the caster effect on the front wheels). Things get
a bit mixed up after that though. For me at least

FGED GREDG RDFGDR GSFDG