PDA

View Full Version : tutorial for dangling cords on a robot?


Gremlin
04-18-2003, 02:14 AM
I'm curious about how I would go about animating dangling cords on a robot.
What I was thinking was making the cord, controlling it using bones and SplineIK and then making clusters out of the end CV's... constraining those CV's to something on the robot.... which was as far as I got. Im still stuck on how I would go about getting the part of the cord in the middle to dangle...

anywho, does anyone have a tutorial on this or a method that they know looks good?
Thanx a bunch! :D
Cheers,
:beer:

dmcgrath
04-18-2003, 05:41 AM
check
http://www.digital-tutors.com/digital_tutors/index.htm

and

http://www.lostpencil.com/

for free stuff. You basically have the right idea, but you could add some particle dynamics to the clusters and really have the thing so it is a hands off operation.

Gremlin
04-18-2003, 07:38 AM
lol, im slow... you need to post some direct links man, I cant find anything on those sites (except an intriguing wheel expression tutorial... I tried that once and I failed miserably, its free except for shipping I might have to get it just because) :D
Cheers,
:beer:

nevermind, I found the secondary motion tutorial on the site... Looks interesting, it would definitely work for an antenna on a car, I just hope that if I were to cluster/constrain the end particles for the softbody.... that the middle particles would act like a cord and not a springy rubber thing :hmm:

dmcgrath
04-18-2003, 09:03 AM
I might have time to try something out at school tomorrow, I'll let you know if I can get something working. But I think you can apply the same strategy to a cord. You could even use your geometry on the robots body as a collision object, so the cords can hit his body and not pass through it.

dmcgrath
04-19-2003, 06:04 AM
Okay, I'm messing around with the tut. that exactly explains what you want to do. It seems to work well, so I recommend trying it out.

http://www.visualart.ro/tutorials/cablu/cablu.htm

I just got the resource from this forum newbie. The guy really did a great thing for us.

http://www.cgtalk.com/showthread.php?s=&threadid=56197

Gremlin
04-19-2003, 08:04 AM
awesome, thanx dmcgrath and thank you borisb2!!
I'm runnin' through the tutorial right now! :D
cant wait to play with it
Cheers,
:beer:

Gremlin
04-20-2003, 05:37 AM
heres what I came up with after following the tutorial and changing some of the settings to my likings...

:::http://www.hellrender.com/cable_wire.avi (215kb)
but, here are 2 playblasts of the cable... heres the cable itself:

:::http://www.hellrender.com/cable_effectors.avi (167kb)
and heres the cable's effector rig (my personal name for it)

Cheers,
:beer:

dmcgrath
04-20-2003, 08:27 AM
Looks pretty good. How about trying to attach it to something and swing it around a little? See if it does what you want, and drop us some more avi's.

:thumbsup:

Gremlin
04-22-2003, 08:17 AM
it does what I want... i guess, but... 2 problems:
- one) getting the cable to NOT pass through other objects AND itself (thats important)
- two) getting the cable to be really stiff in some areas (like, towards the ends, for reasons I cant explain (i'd have to show you)

I think I might have a tedious method for making the cable not pass through itself, but It would only be practical it the cable was a main part of animation (like the hose of the main characters flame thrower) otherwise, it'd be the death of me if I had to do it for more than like 5 cables!! :surprised
Cheers,
:beer:

Hugh
04-22-2003, 09:01 AM
As far as getting it to be stiff at the ends, how about having two CVs at either end, both controlled by locators, and the rest done with dynamics - this would keep the tangent at the very end constant (I'm assuming your pipe is coming out of some opening...)

dmcgrath
04-22-2003, 07:36 PM
Yeah, that was a porblem I thought of too. If you are using joints, try to limit their rotations. I'm not sure if this will work but you could try. Or use dynamics with collision on them. Then it will sense it hitting something and try and force it away.

Hugh
04-22-2003, 07:55 PM
If you were to go the dynamics route (which, I think, would give the best results), you'd need to have a few more CVs and dynamic cubes on there. You might be able to fake it by somehow stretching the boxes so that they touch each other, but then you'd have to somehow stop them from spinning.

The best way would be to have more cubes (I almost think spheres would be better here) so that they are almost touching, or at least don't have the space where a sphere on another cable can get through....

If I had more time, I'd try and get a multi-cable system up and running now, but I'm afraid I am just too busy right now...

Gremlin
04-23-2003, 04:03 AM
Yah, my method for getting the cable to not collide with itself (the one that I said was tedius) was the effector rig with massive amounts of cubes/spheres controlling the CV's and since those objects are rigid bodies, they wouldnt collide, thus the cable wouldnt pass through itself, and as far as having the ends stiff...

THATS BRILLIANT, it'll work perfectly... I cant wait to test it on something... :)
Cheers,
:beer:

CGTalk Moderation
01-14-2006, 11:00 PM
This thread has been automatically closed as it remained inactive for 12 months. If you wish to continue the discussion, please create a new thread in the appropriate forum.