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'Random' Front End Crash Possible Fix?!

Started by Myst1cPrun3, June 17, 2020, 08:30:28 AM

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Myst1cPrun3

June 17, 2020, 08:30:28 AM Last Edit: June 17, 2020, 08:35:45 AM by Myst1cPrun3
After some testing, I believe I have come up with a theory and a possible solution to the seemingly random front end crashes, as well as the issues with camber changes mid corner.

(Thinking MG hairpin at Victoria)

I did touch on this in a previous topic before it was moved, as it got way off the original conversation point. (As much my fault as any that was so I apologize)

Now:

Until I started fiddling with tyres, I thought the front end crashes on camber changes was because of the suspension, and a lacking part in the simulation or mod..

However, in the tyre files, max lean can be set using the DX1 and DY1 values.

Now this differs per front and rear tyre so you can have a tyre have a larger max lean angle than the other.

The bike will only lean to the angle of whichever tyre has the smallest max angle.

So for instance if you let the front have a higher max lean angle than the rear, it is the rear that'll determine the total bike lean.

This becomes important in camber changes.
It's no secret the front tyre is narrower than the rear, so in terms of lean angle, it has a slightly different steering rate it seems. (Not sure on Reasons or physics behind this just how it seems)

If you are on the max lean angle of a tyre, and then the camber changes, the bike does not get stood up, the lean angle changes to beyond the maximum set value in the tyre file, and a crash occurs with seemingly no warning. Typically these crashes are front end crashes as that's the narrower tyre and it's also what it's the camber change first.

As a result I found giving the front tyre 0.1 extra lean on the  DX1 and DY1 values when compared to the rear tyre helped a lot.

This extra angle doesn't affect the bikes handling on the flat, as the rear tyre will be the limiting factor, but when the camber changes, it means the front doesn't simply 'fall off the edge' like is known to happen in GP Bikes.

This isn't to say you can't crash, you can, it just adds a bit of control of the bike over camber changes.

Here is an example of the M2v2 at the MG hairpin, where I was being quite aggressive on approach, and could make the apex confidently, despite the known issues.


It is a marked improvement, but I am going to do more tuning when the 'big tyre update' drops for the v2

Myst1cPrun3

TLDR:

 allowing the front tyre of the bike to lean more

(Changing the DX1 and DY1 values in the tyre file)

Makes the bike more consistent and predictable through turns with camber/elevation changes mid corner

doubledragoncc

Is Piboso also allowing for roll rate of the tire ie the speed at which it can acheive its max angle as the rear is slower than the front and in the custom bike industry a killer to the handeling or rather lack of it on custom bikes. I know its not a race bike but the principle applies so I was wondering if roll rate is used? thinner the tyre faster the rate and if the rear cant roll as fast as the front it causes the front end to dip to one side very harshly.

DD
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Vini

You are not pushing the front at all in that clip because the rear is sliding so much.

In any case, for the M2 the issue is probably also in the VR tuning and suspension.
Even without any camber changes, just rolling through a corner at max. lean without throttle makes the front wash out sometimes. If there is even the slightest bumps it's over as well.
In addition, if you try to stand the bike up aggressively, the VR just locks the steering at max. lean and makes the bike crash.

...Victoria is the worst track for testing BTW.

Myst1cPrun3

Quote from: doubledragoncc on June 17, 2020, 08:54:13 AMIs Piboso also allowing for roll rate of the tire ie the speed at which it can acheive its max angle as the rear is slower than the front and in the custom bike industry a killer to the handeling or rather lack of it on custom bikes. I know its not a race bike but the principle applies so I was wondering if roll rate is used? thinner the tyre faster the rate and if the rear cant roll as fast as the front it causes the front end to dip to one side very harshly.

DD

Each tyre has its own individual value that can be set, and as a result it can drastically change the steering behaviour of the bike from my testing.

Due to the bikes Maximum lean angle being based of whichever value gives the least angle, and the fact it's an integer value and not a maximum angle, I'd imagine there are some calculations regarding this, however I do not know enough about it to make a definite statement.

Quote from: Vini on June 17, 2020, 12:04:50 PMYou are not pushing the front at all in that clip because the rear is sliding so much.

In any case, for the M2 the issue is probably also in the VR tuning and suspension.
Even without any camber changes, just rolling through a corner at max. lean without throttle makes the front wash out sometimes. If there is even the slightest bumps it's over as well.
In addition, if you try to stand the bike up aggressively, the VR just locks the steering at max. lean and makes the bike crash.

...Victoria is the worst track for testing BTW.

You're missing the entire point of this thread...

The front tyre seems to wash out unrealistically on camber changes due to the set max lean angle in the tyre (using the values instated above) then it washes out. (Bumps included)

Pushing the front is irrelevant as it happens as long as the stick is on max travel, as is the track. Victoria just has a known spot where this occurs which is shown in the video.

As for the vid, that's the V2 M2 which has all new vr settings and suspension, and although isn't perfect, it's much more ridable. But also not relevant here as I'm not talking about corner entry or exit.

It's camber/surface/elevation changes mid corner...

This topic is now locked as I feel it's going to go astray again.

Fell free to edit the above values to understand what I mean.