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View Full Version : Cloth FX settings for a cable



marchermitte
05-19-2010, 04:03 PM
Hello! I'm trying to setup a scene with a polychain. I have 4 pulley spinning, with enough roughness and friction to pull the polychain. Everything works fine, except I'm not able to find the appropriate settings to prevent the polychain from behaving like rubber. I intend to use Its deformation to drive a rigid chain spinning around the pulley and right now It hangs and jerks like rubber, not like metal. I tried setting the stretch limit to 0.01%, increasing the viscosity, substructure, etc. Doesn't change much.

Any idea?

Thank you!

Marc

UnCommonGrafx
05-19-2010, 04:13 PM
Do it with bones.

marchermitte
05-19-2010, 04:41 PM
Not an option in my case. I tried about everything for this effect:
I have an animated limb, almost like a tentacle. It has a spinning blades chain in Its middle. The pulley are hidden and parented to the tentacle's bones. The Morph trick works but can't give me the proper motion blur (the spinning is too slow) and the tentacle looks blurier than the blades. This one should work, I've seen some tank thread animated with this technic. Only the settings in clothFX don't seem to work for me, the polychain is looking way too elastic for what I want. (Metal chain)

UnCommonGrafx
05-19-2010, 04:50 PM
Hmm,
Then see if you can do it to something simple and fxlink it to the final object. Dunno, stabbing here...
Have a simple scene to look at?

Dodgy
05-19-2010, 07:20 PM
Maybe this is something you want to look at.

http://www.youtube.com/watch?v=Joni3mn8M3s

marchermitte
05-19-2010, 10:58 PM
Hey, Mike! YES, this is exactly what I was looking for! I setup my scene just like yours except that the clothFX settings didn't work for me!
I'm trying yours on my scene right now!
I was expecting advises and you're giving away the whole scene!
BTW, thank you so much for many of your plugins I'm using on a regular basis! I'm one of your (numerous) admirators!

Dodgy
05-19-2010, 11:18 PM
One thing you can do which you might have missed is use the Polygon Size control. It allows you to have objects which are over sized shrunk down to tighten them around collision objects. If you go too low it can obviously cause problems (I went to 80% and I got twists in the cable) but it does give you a bit of leeway.

marchermitte
05-19-2010, 11:45 PM
Well, I tried your settings and 10000% spring just make my low poly proxy vanish. I lowered the settings until I get something "stable" but still get the chewing gum fx. My firsts settings where even a little more adapted to my scene.
I made the low poly band from a simple polychain that I extruded... I guess you've done the same. And whether I use the poychain or the low poly band, I still get the Chewing gum FX. Crazy! How come 0.1 or 0% stretch doesn't do what It's suppose to do, a mesh that doesn't stretch at all?

Dodgy
05-20-2010, 12:21 AM
Can you post your scene?

marchermitte
05-20-2010, 01:18 AM
If you're willing to waist a little bit of time on my project, that's more than generous!
I removed the tentacle and the blades (too heavy)
Thank you so much!

Marc

Dodgy
05-20-2010, 03:03 AM
Okay, for a start, NEVER USE YOUR RENDER OBJECTS FOR DYNAMICS! That's my number one rule...Unless of course your render objects are very low poly! :) You have 3000 polys in each of your collision wheels. That's a lot for the dynamics to calculate. I made low poly proxy objects of 146 polys each and parented them to the wheels and used those as your collision objects. Your tape needs only to have as many segments as teeth on your chain, maybe double if collisions are going through. I made it 110 (my old extrude setting for my object) and now I get about 20 frames a second calculation, not several seconds per frame. This makes it much easier to tweak. This also means you can cheat like a basket to get the results you want!

You also need a bit of give in the Stretch Limit value so it won't spaz out. Putting it very low puts a lot of strain on the calculations because they have no wiggle room. I also then upped the spring and substructure settings. Anyway, it's behaving much more nicely now!

marchermitte
05-20-2010, 03:47 AM
Your the best Mike!!!
About the collision meshes resolution, I started low but the polychain was going through them. So I thought that increasing the res would help... obviously I was wrong!
Well, I guess I have to work on my dynamics skills a little more!
I just have to tweak and try to make the chain go faster without breaking the balanced setting you came with.

Thank you! I'll donate something on your website so that you can have a few beers on me!

Marc

Dodgy
05-20-2010, 06:14 AM
Yeah, getting the mesh res right is a matter of knowing what to tweak, res or settings. If you use a sub-d object as the proxy, you can do quick tests by increasing the subdivision levels, or slice up particular bits to give better results.

Thanks for the contribution!

nightrider
04-08-2013, 09:56 AM
Hi!
I get lott off error when I try to open this
MasterHandler plugin with name Fprime
etc do you have all that plg thats be need to run this ??




Okay, for a start, NEVER USE YOUR RENDER OBJECTS FOR DYNAMICS! That's my number one rule...Unless of course your render objects are very low poly! :) You have 3000 polys in each of your collision wheels. That's a lot for the dynamics to calculate. I made low poly proxy objects of 146 polys each and parented them to the wheels and used those as your collision objects. Your tape needs only to have as many segments as teeth on your chain, maybe double if collisions are going through. I made it 110 (my old extrude setting for my object) and now I get about 20 frames a second calculation, not several seconds per frame. This makes it much easier to tweak. This also means you can cheat like a basket to get the results you want!

You also need a bit of give in the Stretch Limit value so it won't spaz out. Putting it very low puts a lot of strain on the calculations because they have no wiggle room. I also then upped the spring and substructure settings. Anyway, it's behaving much more nicely now!

erikals
04-08-2013, 12:17 PM
yo, just hit "ok" fprime is not needed...

erikals
04-20-2016, 10:02 AM
just a video preview of post #11

"SCENE web Cloth"