Ok I'll try playing with it a bit. BTW is it correct to use the 'Remaining travel' figure when tuning the rake angle?

Tried it some time ago on a FZR set with both axles at ~3 Hz (75;120), the level ride stuff says:

Front given rear: 2.42 Hz
Rear given front: 3.93 Hz

That's a split of 20 and 30% respectively. If I choose 'Stiffen' the rear spring end up at 205 N/mm with fronts still at 75.

So what am I missing here?

BTW can anybody explain how the level ride stuff works?

Quote from Michalxo :

it was only a joke nothing else

Mine was sort of one too

That's understood, I was thinking something analytical (ala VHPA) or .raf files analysis, maybe looking at slip ratio or torque at the wheels? I'm not on windows now and can't remember exactly what data is available.

Just popping in to report this small error:


Disregard if it's already been reported

There's a small boxy thingy you can use to turn pedals into a USB device.

http://www.leobodnar.com/products/DFPG25conn/

It says "DFP or G25 or generic 3-axes pedals"

BTW there's going to be a movie about Phil Hill with Tobey Maguire in the lead -with that face?! :banghead:

Quote from Michalxo :

<spam> Finally I know where the problem is. It's all that world's crisis fault! :banghead: </spam>

That only proves you didn't read this thread very well otherwise you should already know that:

Quote :

Then we look at the subprime crisis for example, losing 5 billions for a bank may seem HUGE when looking at the face value, but <blabla> [it] isn't *that* bad

That's why most governments have poured taxpayers' money into the pockets of private banks, because it was not that bad!

So the LSD is 100% locked as long as the torque difference is less than the preload?

And how do you calculate the 'critical' preload value that turns the diff into a locked one? in LFS?

Quote from Bob Smith :

You avoid the wrath of the anti-locked diff brigade.

Our torches and pitchforks can't be misled so easily

Quote from ADX.14 :

I just wanted to show the complete picture of LFS progress objectively.

Nice, thanks for taking the time to do that and sharing your work with us.

What's the difference between a locked diff and a LSD with preload set to a sky-high value?

Quote from Not Sure :

This is exactly why we need to have different servers for different controllers.

I don't think the LFS community is so big we can afford to split people on different servers based on the controller they're using.

Quote from Bob Smith :

Any manufacturer who knows what they're doing must know what this curve is going to look like before the build the spring in the first place

That's understood.

I was suggesting it's not impossible, even for an individual with some money to burn, to find out the hard data.

Googling a bit around I was able to find interesting stuff regarding the GTI which is why I was mentioning it. The same holds true for many popular models, and I think big repair shops also have huge DBs with technical data about an almost endless list of models.

Quote from Bob Smith :

I'd imagine it varies quite a bit between cars. I do know that for the RaceAbout, real spring stiffnesses were supplied but that for the Scirocco, they were not.

Spring stiffnesses are just a tiny bit of the puzzle, I would have expected the average 'manufacturer' to provide enough information to Scavier to model the car with a certain degree of accuracy - certainly not because they are happy to share it, but because I put faith in Scavier not accepting too many compromises about this.

The discussion about setting up rF reminded me of that post of Shotglass saying Linux is a hobby because to get it to work correctly takes entirely too much time.

I'd say setting up FFB in rF is a hobby itself I have enough already to learn about driving and setups without having to cope with dozens FFB settings, and the increased complications of having to tell whether is the set, my driving or the FFB settings that need addressing.

Up to a point I was in a mood to try rF out, but that part really killed my interest off - Maybe if one has extensive knowledge of the car and track he's going to drive... maybe...

Quote from ToxicKlay :

This should be a T.V. advertisment for LFS.

"Look! Mommy! the RAC is so low the steered wheels are touching the fenders. It must be that awesome sim I heard about, where your car can take off like a plane on 1ft high curbs and when you land you have neither damaged rims nor bent suspensions arms! I wonder why they didn't throw in one of those extremely realistic skyrocketings off the red-white barriers! want one ASAP!"

Slo mo should be for showing off the good things in LFS not exposing its flaws - JIMO and back to my corner

Quote from ColeusRattus :

You still mix up developement speed with the frequency of released patches.

Sound analysis, its only shortcoming is we commoners can only observe two things:

1) the frequency of released patches
2) amount of information released about ongoing development

With 1) being a little on the slow side, and in absence of 2) people start going astray and come up with theories which to you may seem as logical as the invasion of earth by reptilians, still they have the same justifications as your patience.

The only difference is you have faith and they've not. That's why expectations should be managed.

Quote from zeugnimod :

Or to ignore the idiots.

Which unfortunately is very hard, I constantly fail at doing so myself.

The problem with idiots (discarding the idea you were implying I am one too), is everybody need to be able to recognize them as to neutralize their statements.

I'm sure you noticed the logical loop in the previous statement, as if everybody would be able to recognize them, they would be able to do so as well and instantly stop being idiots.

Hence the popular saying 'never argue with an idiot because others may not be able to notice the difference'

For me the inevitable conclusion is even if idiots and idiots only are <cough> moaning, the effort associated with recognizing one means the bad word of mouth idiots create has the very same value as the one that would be created by a group of select and very knowledgeable people pointing out issues with LFS and its management.

To a degree - it doesn't matter if someone is an idiot or not, as long as the thing he/she's saying has some truth in it

Quote from Bob Smith :

Good luck finding such a curve though.

I read there are instruments to find out the spring stiffness, for a curve you'd need something quite sophisticated I suppose.

I wonder how the guys at iRacing handle this they have stated sth along the lines of testing the cars in their labs IIRC.

Quote from Bob Smith :

I also agree that, with good diagrams or access to a real car with a tape measure, a very reasonable estimate of the motion ratio could be obtained.

So VAG just gave em a CAD drawing of the body? They weren't interested at all in the handling then.

Was it the same with the other RL cars in LFS?

Quote from zeugnimod :

People will get bored of anything in a few weeks/months and start moaning again.

Hence the only equilibrium solution is to stop developing LFS so people will go moan elsewhere. Great!

So the statement is falsified.

Last edited by NightShift, Sat 25 Apr 2009, 15:26.

I think I understand where you coming from - i.e. you say what matters the most is the amount of the error. If this is small enough you won't notice it because of flaws in LFS or limitations of the controllers masking it, right?

I still have some questions if you don't mind - I find all of this very interesting.

Quote from Bob Smith :

For choosing a value, you can pick a value in the range of spring deflection that is most often used given the driving conditions you expect the vehicle to be put through.

So you would use an iterative process, using what you think is a good guess or the softest value and then progressively increasing it through testing on various LFS track configs?

Quote from Bob Smith :

Finding out the real spring rates is only so useful if you know the motion ratios that go with them.

But even if you don't have the ratios you could still extract the springs curve and use it adimensionally, am I wrong?

And motion ratios could be estimated through a geometric study of the suspensions?

That would be easier if they had CAD drawings of the suspensions and not just the body - but there's a lot of stuff available online and offline the thing being basically a refactored GTI.

Assuming the devs can't come to a good estimation - if the motion ratios are 'made up' then it makes no difference whether they choose to go model progressive or stick to constant stiffness, the springs would still be 'made up' as well

@OP - I can do without a true dev blog, but it would be nice if they resumed posting some updates like they used to do (http://www.lfs.net and browse news archive)

Also some things Scawen says on the forum could be slightly edited and posted as news, so that one doesn't need to sift through his posts to find out.

Quote from Machine-V8 :

The major difference is DFGT's 900 vs F430's only 270 degrees of rotation but since I haven't owned a wheel before, I can't see how this could be such a big disadvantage.

It is a matter of taste, some people like/find convenient to set 900° wheels to a small lock, mainly before it makes easy to countersteer quickly. Of course changing the lock affects the feeling you get through FFB.

If both could be had for around the same price, I'd buy the GT no question. If instead, the Thrustmaster is significantly cheaper, it becomes a matter of personal priorities. I'd still save to get the GT.

Quote from maggot :

so, it sounds like all (or most) of the small downsides can be fixed if so inclined... I'd love it if you came back to this and refined it. It's a very promising endeavor!

+1

Given the limited setup options, hardcoding the curve looked like a viable solution to me. Certainly far from being the cleanest, most elegant one - but it would still make the VWS closer to the real thing without the need for more changes.

Quote from Bob Smith :

how do you decide what shape of curve to hard-code?

So if you go with a constant stiffness spring, how do you choose its value?

BTW if the VAG guy didn't hand out spring information (shame on them), I'd take a look at the Golf GTI springs, the car has been out for some time, shares a lot of components with the Scirocco, and thus is reasonably similar. If you get ahold of a couple springs, it shouldn't be too hard to extract a realistic looking curve.