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koffiekoekje
10-31-2006, 08:02 AM
Hello,

On this moment I'm making a simulation of a bear (rag doll) witch falls from the stairs. The body is controlled by proxy objects with a gravity influence. The proxies are also connected with hinge constraints.

For example: the upper arm proxy is connected to the upper body with 2 hinges. Between this hinges there is a extra shoulder proxy. By doing this the arm can move up / down and back / forward.
I used 2 hinges instead of 1 pin constrain because a pin constrain also moves around its axel, witch I used first. When I used the pin constraint the skin twisted like a candy wrapper during the simulation. Than I came up with the idea of using the 2 hinges. In first I thought that did the job, until this also started to wrap.

Is there a solution to solve this problem?

http://i86.photobucket.com/albums/k117/koffiekoekje/candywrapper.jpg

ps. I also tried using Directional hinges, but that doesn’t work at all.

koffiekoekje
TwinsenDude
11-01-2006, 08:49 AM
Hey, I don't know if this'll work, but have you tried locking the rotation in that axis for the proxy object?

Just bring up the proxy object, and let's say it's the X axis. Select the X axis as if you were going to key it and right click>Lock selected
koffiekoekje
11-02-2006, 03:38 AM
Hey, I don't know if this'll work, but have you tried locking the rotation in that axis for the proxy object?

Just bring up the proxy object, and let's say it's the X axis. Select the X axis as if you were going to key it and right click>Lock selected

I just tried it, it gives me a different result but the skin still twists like a candy wrapper. I also tried to lock the rotation on de hinges, didn't seem to work. Anyway thanks for the tip. :)
I also tried rotation limits for the joints witch are controlled by the proxies, but it seems that the proxy movements overrule the joint limits.

Now I’m going to try different levels of damping and friction, maybe that does the trick.

I'm beginning to think the problem got something to doe with the point of mass ore something :dont know

-edit-
http://i86.photobucket.com/albums/k117/koffiekoekje/ProxHing.jpg
koffiekoekje
12-04-2006, 08:15 AM
I hoped there was an easy solution. But I worked around the problem by editing the rotation axis after baking the simulation...

That night I had a dream about keys, they were very abusive :’)
laxman
12-04-2006, 02:36 PM
it'll probably be the first of many:)