View Full Version : cloth tunnel.

 =LuxX=04 April 2006, 12:57 PMHi guys, Im new with cloth and i've got a little question. ( at first srry for my bad English ) Im making a tunnel with cloth it is the tunnel where Aleksei Leonov came treu when he started his first space walk. here can see what i mean and what te problem is. ( te tunnel is flateble) http://student-kmt.hku.nl/~tjeerd0/explain.jpg i have made 2 drag points ... one on the top and one half way. the locaters are on the bottem of the tunnel where the vertex have to go to. when im only using 1 drag ( the one on top ) evrything is going oke. but i need the cloth to stay to getter. like in the picture when it is closed. ( im animating it from open to close and later i reverse the animation) when i make another drag in the middle avrthing is going wel till frame 33-34.. ( you also can see this in the JPG) 33 is going .. oke but at 34 damn it totaly flips like hell... does anyone know a solution. ( if u know what i mean)
FloydBishop
04 April 2006, 03:02 PM
You might be better off going with softbody dynamics and setting up goals for the closed position.

04 April 2006, 03:18 PM
Seconded. Softbodies are a better way to go for this.

=LuxX=
04 April 2006, 01:17 PM
pfjeeew... thnx

thats totaly new for me.. hmm but i got a good key that helps me ;) F1

il go and try....

tpalamar
04 April 2006, 05:44 PM
The best way to do this with cloth is to add rings of locators or geometry into the cloth at various points. The thing with cloth is that you must build it just like the real thing. It is that physically accurate. If you look at your tunnel you will notice that there are metal rings inside of it. You can see them when it is folded. If there weren't the material would just go slack. If you put some kind of additional node structure in the cloth, could just be Nurbs curves spread uniformly out through the tunnel, then constraint rows of cloth points to the rings. From there animate your rings or Nurbs curves coming together like an accordian. This is just the beginning but it should get you on the right track. Stick with Cloth.

Todd Palamar
www.speffects.com (http://www.speffects.com)

=LuxX=
04 April 2006, 07:24 AM
The best way to do this with cloth is to add rings of locators or geometry into the cloth at various points.

Todd Palamar
www.speffects.com (http://www.speffects.com/)

Hi thnx..

I 've made some differents and it going better already ... but stil ive got a little problem what looks like I had first. it's maby hard to explain but ill try.
I have made som drag handles to fold the tunnel the right way. but here it comes, still ( now ) when my time line reaches 87 -88-89-90 it is ****ing up it self. the shuttle ( the orange triangle) starts to rotate en mij mesh is all fliping with it. is there a way to hold the shuttle ... he still has to follow the path but may not rotate.

ow I just noticed that the transformconstrain of the shuttle is also going crasy as hell when i reach frame 87. all of them are going their own way.. ( it is posible to slect more vertexes points to grab isnt is?)
can someone help me ???

=LuxX=
04 April 2006, 10:04 AM
Seconded. Softbodies are a better way to go for this.

oke im also trying soft bodys but ... what do i need for that.. it is totaly new.. what kind of fields do i need to use? and can u give me small hints why it is better to start frome the closed position?

thnx

tpalamar
04 April 2006, 11:51 AM
Okay, here it is. Get rid of the drag control. You do not need it. Drag controls are used to help place the cloth prior to animation, not during. Check out the two images I attached. First create several NURBS curves and spread them out evenly. Next create two panels, one in front of the curves and one in back. Seam the panels(garments) together. I used a resolution of 400 but you might want to go higher. Select a row of vertices around a NURBS curve and constraint to transform. Repeat for all curves. Animate each curve compressing or expanding. Run the sim.

Let me know how it works out.

=LuxX=
04 April 2006, 01:24 PM
JHaaahoeeeeee!
YOU ARE THE MEN!.

it works.. ( a small version) now im goin to try it in the final shape... ill shall put a link here when its done..

Thnx A lot!!

04 April 2006, 02:36 PM
Right on, tpalamar. That solution occurred to me a couple days ago, I think while I was driving home, and I forgot to post it. Glad it worked.

tpalamar
04 April 2006, 02:40 PM
Awesome! Glad to hear its working. I look forward to seeing the finished piece.

I know what you mean Bonedaddy, I do some of my best thinking driving as well.

=LuxX=
04 April 2006, 09:19 AM
okeej .. still working on the thunnel. my bose toled me there are no rings in side.. :S so it has to ... (hmm m how do u say that.. ) foled naturaly... ( i hope you understand) it is like a big sheet that u pick up it zig zag's open... hard to explain when you dont know the correct words.
but any way that is not the problem that is all working fine. But when i start the simulation the tunnel becomes smaller. I've tryed with a colission in the middle but that wont work.
does some 1 know a solution that the tunnel stays the same size?

thnx allot..

fritz8th
04 April 2006, 04:01 PM
Hey LUxX how is the cloth getting smaller? Because with mayas cloth when you run your sim it will usually shrink just to relax. Also your panel size will control how big the cloth size is if you want your cloth to be bigger try making your panel size bigger ill have cases were my panel size will be much larger than the actual cloth object. Hopes this helps if not post back.

Dan

=LuxX=
04 April 2006, 10:07 AM
Hey LUxX how is the cloth getting smaller? Because with mayas cloth when you run your sim it will usually shrink just to relax. Also your panel size will control how big the cloth size is if you want your cloth to be bigger try making your panel size bigger ill have cases were my panel size will be much larger than the actual cloth object. Hopes this helps if not post back.

Dan

Hi Dan,

Thnx for your help,
OKe you know it is a tunnel. It is getting smaller not in the Length but the wide. If i set the relaxed lengte to 1-2 it wont simulate .. dont ask me why but it wont. so i set it to 4. the other tihing u said about the panal size. Where can i find that? I've tryed the Cloth panel resolution factor but that isnt the right one is it?. Also i tryed the locator attributes local scale .. but that is it neither is it ... damn cloth is much harder dan i thought.

tpalamar
04 April 2006, 10:59 AM
Increasing the panel size will only add more material to the cloth. This can eventually result in the cloth sagging. Cloth has to relax. The larger you make the internal rings the wider the tunnel will be. You might want to make them a little larger than they should be. Cloth will still shrink aroung them. It will always adopt to the shape or forces it collides against, whether it be a solid object, constraint, or air. I think what you might be looking for based on the photos you posted is the cloth to be tighter. You can accomplish this by moving the locators or rings out further after you run your local simulation.

One thing you might try after your first local sim is to increase the stretch resistance on your material properites. This will make it stiffer but also reduce its ability to shrink. Try values above 100.

Also the relax frame length simply turns off dynamic forces for however many frames you set it to. It won't have any bearing on the problem you are having.

Hey Dan, good to see you!!! How's cloth going for you?

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