View Full Version : switching from passive to active?

03-31-2010, 04:54 PM

I'm trying to set up a simple dynamics scene. I've got a ground and 2 cubes, I've set the ground and cube1 to be Passive RB and cube2 to be Active RB. I'm dropping cube2 onto cube1 from different heights.

I remember seeing somewhere (ages ago) some way to setting cube1 to be passive until a certain force hits it and then it becomes active. Simulating that its a shelf or something solid that is attached to a wall, one which could take a small weight but not a large one.

I've googled around and can't seem to find anything on the subject. Other than just keying the active channel, but this isn't usefull in a simulation.

I've tried using springs and Nails but neither of these has a breaking threshold (plus spring bounces around all over the place).

can't anybody help me out or at least point me in the right direction?


03-31-2010, 05:14 PM
Hey Harrad,

You can try these two options:

1. Key the "ignore" attribute on the shelf object

2. use active/passive keys

Hope that helps,


03-31-2010, 05:22 PM
if its simple objects, try ncloth (set to act like rigids), and use constraints with glue strength...

like this :)

03-31-2010, 07:58 PM
Unfortunately i'm doing this in maya 2008 and so dont have nCloth... just the standard dynamics and constraints.

I remember seeing it done with expressions, where you test the speed or the collision and the first frame the object is hit it makes it active.


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03-31-2010, 07:58 PM
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