Cloth (canvas) simulation problem

[thechapmanbrothers]

To anyone who can help

I am in the final stages of building a model of the battleship Bismarck (not another one I hear everyone groan) + other heavy units from ww2 and I used a flag tutorial http://www.dezfx.com/HTML_pages/TutorialPages/animatedFlag_1.html.

The flags I created following the tutorial work perfectly. I then deceided to try and cheat and use the same principles in the tutorial to create the canvas covers that wrap around the guns at the gun/turret connection (see pic).

When I play back the animation everything moves as it should, the material sags with gravity and folds up nicely when the gun is elevated, it is when I move the material a certain distance (doesn't matter if it is along any axis) that the material folds and crumples horribly, it looks like it is being blasted by a hurricane.

Has anyone got any ideas on what I can do to fix this problem as it is the only thing holding me from animating. Thanks for any who replies.

[zarroun]

one thing you could do is get your timing first and then animate the turrets without moving the ship. bake the simulation and then move the ship around. This requires careful planning, but will work in the end. Problem is you can't easily make adjustments.

Maya can be tricky with simulations. One day they work, the next day you get useless results. You might have parenting problems or something in that direction. I'd have to see the file itself pr see a playblast of what's going on. I'll be glad to help you out more.

[thechapmanbrothers]

Thanks for the reply zarroun, sorry about the extreme delay in getting back to you but I had to put this project on the backburner.

I will create a quick and dirty render and post it shortly to show what is happening.

Thanks again.

[thechapmanbrothers]

Here is the 'quick and dirty' video of the sim. It shows how the bag starts to deform and explode. I have discovered that if I move the turret very slowly it does not explode but keeps its correct shape but the speed is to slow for what I want.

Thanks in advance for any adive.

[zarroun]

wow, it's been a while :p. It's hard to see what's going on in the playblast, but i think you may have dampening issues.

the exploding is probably because the numbers are too high. It's been too long for me to point out the exact value you have to change. As I mentioned before, if you want to give me a sample file, I'd be happy to look at it.

Maybe what you can do is create a softbody with a goal. then you can paint on how much the cloth moves. And rather than parenting, you should probably use a pin constraint. The outer edges of the cloth would be pinned to the turret, the round opening would be pinned to the barrels.

Let me know if you want to IM me so we can talk more directly.

Syflex (http://www.syflex.biz/) could be another solution, but it's pretty pricey. Check it out, it's a nifty add-on for maya.

[thechapmanbrothers]

I am a bit unsure of your instructions using the pin constraint, I haven't ever used paint but that should be fairly straighforward. Pardon my ignorance but how do you attach the two surfaces together by pinning them and then having the 'canvas' object deform around the turret and barrels.

I looked at a bunch of tutorials but something isn't clicking. If I could trouble you a little more by explaining how you would go about it, a sort of step by step approach only if that is feasible.

Thanks again. PS: I don't have IM, sorry but I will try and get around to installing it.

[thechapmanbrothers]

Sorry, I should have added that I have fiddled and fiddled with all the springs settings. Dampening, tesselation and resilience with the geoconnector with still no luck.

[zarroun]

Sure thing, mate. I will try to create a sample scene for you and tell you what I did. What version of maya are you running?

[zarroun]

is this kinda what you're looking for?
http://www.zarroun.com/temp/turretTest.zip

i made the turret shake to show you that the cloth jiggles when you fire a shot. If you model wrinkles into the cover, they will bend and stretch nicely with the barrel. the step-by-step might be a bit lengthy, so i'll create it for you when you tell me that that's the effect you want.

[thechapmanbrothers]

Thanks mate, thats exactly what I was looking for. It deforms properly yet the edges are still attached to the barrels and turret. One small question is when you move the entire turret say forward like it is connected to a ship in motion, does it still retain its shape yet deform properly when the turret and barrel are moved.

Cheers and thanks again for your help.

[zarroun]

yes, it sure will. you can parent the turret to the ship and the canvas will go with it.

I'll start typing up the step by step then

[thechapmanbrothers]

By the way, I have posted a pic in the shipyard, it is still a bit rough (needs work on lighting and some other things) but gives an idea of where I am up to.

Once again - thanks for your help!

[Archetype]

i see some one is doing a bismarck ;)
will you post a wip @ the forum ?

[zarroun]

all right, i posted the tutorial for you here:
http://www.zarroun.com/tutorials/barrelcover/barrelCover01.html (http://www.zarroun.com/tutorials/barrelcover/page01.html)
shoot me an email if you have any questions. have fun!

[thechapmanbrothers]

:D :D :D :D :D :D :D :D :D :D :D :D :D :D :D :D :D :D :D :D :D :D :D :D :D

Thankyou Zarroun,

I followed your tutorial and it worked perfectly. I did some quick tests applied to my Bismarck model and it does everything I want it to, I changed some of the values to suit what I wanted. Namely the bind skin values but other than that it worked great.

I am going to create a quick render over the next few days and will post it to show my results. I am so pleased as I can now start animating and rendering my scenes.

I would like to say again thankyou very much for taking the time to create the tutorial, it is extremely appreciated and I hope to be able to return the favour some day.

[zarroun]

Hehe, no problem, mate :D. I like solving problems like this and i'm glad i could help you out. Looking forward to seeing your animation! let me know when you got it up.

P.S.: the location of the tutorial has changed, to make future tutorials a bit easier on me, to this:
http://www.zarroun.com/tutorials/barrelcover/page01.html