Ground Friction and Resistance Index

All about making tracks for MX Simulator
haggqvist
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Re: Ground Friction and Resistance Index

Post by haggqvist »

Damn, I just uploaded new layouts of Sorketorp and updated versions of the old ones....
I'll try it out and see what happens.
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jlv
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Re: Ground Friction and Resistance Index

Post by jlv »

Shadow wrote:Jlv, my thinking was along the lines of "could the settings be made to simulate the front wheel digging into the dirt and resisting acceleration like it happens in real life". I'm guessing this could be made also with the separate rear and front wheel rolling resistances adjusted so that the front wheel has more rolling resistance than the rear and both have less uncompressed resistance than compressed. Could be something worth looking into I think.
Dug in would be more compressed though. That's why it doesn't make any sense. You have it set for more drag when the wheel is just lightly skimming the ground.
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Sweendoggy
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Re: Ground Friction and Resistance Index

Post by Sweendoggy »

I think the rear wheel gets more "rolling resistance" than the front in real life, depending on what you are counting towards that resistance...i.e. front tire is usually really free and really light on the ground relative to the rear...

Also, do you guys honestly think that if you rode in real life as fast/aggressive as you do in this game, that your front tire wouldn't slip out? Same thing goes for going too slow, you would just fall over in the turns. I personally think the front tire washing out is pretty true to real life...If you know the threshold, your tire won't slip out. In real life you can't ride a flat corner on ANY dirt (traction) above a specific speed/acceleration without your front tire washing out....

prove the above wrong and I'll join back in this conversation lol
yzmxer608
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Re: Ground Friction and Resistance Index

Post by yzmxer608 »

It's a lot harder to use the bike with barely any gas though, even half throttle on a trigger hardly has much power.
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Shadow
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Re: Ground Friction and Resistance Index

Post by Shadow »

jlv wrote:
Shadow wrote:Jlv, my thinking was along the lines of "could the settings be made to simulate the front wheel digging into the dirt and resisting acceleration like it happens in real life". I'm guessing this could be made also with the separate rear and front wheel rolling resistances adjusted so that the front wheel has more rolling resistance than the rear and both have less uncompressed resistance than compressed. Could be something worth looking into I think.
Dug in would be more compressed though. That's why it doesn't make any sense. You have it set for more drag when the wheel is just lightly skimming the ground.
I was also assuming that the front wheel won't really become compressed under acceleration in the game unless one hits a bump or lands a jump. Honestly, I don't really know why that change improved the bike's handling so much.
Sweendoggy wrote:I think the rear wheel gets more "rolling resistance" than the front in real life, depending on what you are counting towards that resistance...i.e. front tire is usually really free and really light on the ground relative to the rear...
Myeah, perhaps in constant motion but when the bike is accelerating, the rear wheel is spinning faster and pushing the front wheel forward because it takes a bit of time before the front wheel starts to roll with the same speed. Or at least that's been my understanding, somebody correct me if I'm wrong.
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Sweendoggy
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Re: Ground Friction and Resistance Index

Post by Sweendoggy »

^^ makes sense, I was thinking about it a bit wrong...(along the lines of the rear tire having to overcome much more inertia to accelerate than the front) but it makes sense that if you just say the rear wheel is already accelerating and the front tire is the "limiting" factor as there is no acceleration applied to it directly, but only from the rear tire pushing it, thus, the rear tire is pushing forward so to speak and the front tire is working against that, as in the rear tire has to push it along (simply stated)...I think that is more of an issue to have in the physics of the actual game, than it is to have in a traction file tho. I'm sure there is a differential equation to describe the relationship you are talking about, sort of like "drag" and I'm sure JLV already has something like that in the physics engine.

I still say the front tire washing out isn't as bad as many think.
chris465
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Re: Ground Friction and Resistance Index

Post by chris465 »

Sween the front tire still washes out with what he has done but it seems to feel more realistic to me anyway. Now when it's planted in the corner it stays there more like real life. Just my opinion.
Sweendoggy
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Re: Ground Friction and Resistance Index

Post by Sweendoggy »

I was just talkin Physics, as I love to learn what I can, and I am sure shadow knows more about physics than me. I still haven't played that track tho :(
Prologue
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Re: Ground Friction and Resistance Index

Post by Prologue »

There are always opportunities for interesting things to happen when you are at the edge of losing traction. For instance, in real life the tire could be vibrating side to side as it grips, breaks free again, catches again, etc. producing, on average, a higher grip than was experienced just before the slipping started. Things like this can make non-intuitive results happen when compared to the simple model. All that I am really saying is that maybe a simple on-off between sliding and catching isn't the best way to capture what is happening in real life. Shadow's ass-backwards way of tweaking stuff may be just a lucky setting that somehow captures what is happening.

The discrepency between the front wheel gripping better at the edge of traction and the rear following a more conventional on-off type sliding could be justified by the higher stiffness of the rear wheel, producing a higher resonant frequency and taking it out of the regime where this funny effect happens. Basically I am saying that it is plausible, but I have no idea if this is what happens in real life.
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Garasaki
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Re: Ground Friction and Resistance Index

Post by Garasaki »

I'd say there is no question that a front wheel has a stiffer sidewall then a rear wheel.

Of course tire pressure is a personal thing, but I always liked my front about as low a pressure as my rims would take it, but I usually liked the rear pretty pumped up. This would increase the difference in stiffness between the front and rear tires.
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Prologue
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Re: Ground Friction and Resistance Index

Post by Prologue »

Either way works though, I really have no idea which one is stiffer.
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karlwb
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Re: Ground Friction and Resistance Index

Post by karlwb »

Shadow wrote: "could the settings be made to simulate the front wheel digging into the dirt and resisting acceleration like it happens in real life".
yeh,thats what rolling resistance does when its set right

Shadow wrote:
separate rear and front wheel rolling resistances adjusted so that the front wheel has more rolling resistance than the rear and both have less uncompressed resistance than compressed. .
what you're suggesting is a BS way to compensate for the trend of crap "fast" traction settings (overall rolling resistance too low) and make them a little more ridable, you exchange good handling for increased power delivery........

in effect the tile info system is being hijacked to bump engine output!

all who think the bikes are underpowered should lobby to get the engine power output raised to a more realistic level,thats a better solution IMO than to screw up the terrain modelling or bike physics!

:evil: rant over HAPPY NEW YEAR :lol:
Shadow
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Re: Ground Friction and Resistance Index

Post by Shadow »

um.. no

How I set the traction for those tracks improved the front wheel's control over rough terrain. Which definitely was/is a problem.
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dearnhardtfan7
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Re: Ground Friction and Resistance Index

Post by dearnhardtfan7 »

karlwb wrote: all who think the bikes are underpowered should lobby to get the engine power output raised to a more realistic level,thats a better solution IMO than to screw up the terrain modelling or bike physics!


JLV has shown that the bikes are actually overpowered by 5 hp
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jlv
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Re: Ground Friction and Resistance Index

Post by jlv »

That's only true if Transworld's dyno is the one that's off. They seem to have permanently stopped publishing dyno charts with their tests now, so I probably will be switching to the lower numbers from motorcycle-usa at some point.
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