help! particles do not repel.. new to Houdini here

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I have about 100 particles moving around in a random motion. I need to make them avoid colliding with each other.. is it possible? (better be) ;-)
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Use the Interact pop.
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i am .. but some of them still keep colliding. is there a particular attribute I need to setup/use ?
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Hmmmm that would be a cool feature, where you could assign particles to be negative or positive. Hence positive particles would always repel each other but would be attracted to a negative particle. :wink:
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This might be overkill but I like to use actual point-RBD's in a dynamics simulation. This ensures that they will hit and deflect from one-another.

If they are flying around randomly you can treat them a lot like particles and use noise feilds in various forces like gravity / uniform / and wind.

Another thing is that if you want to put them in a container make sure the volume based collision is turned off. This turns it into a thin-wall collision and works much better for that kind of stuff as long as the substeps are turned up.
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havana
Hmmmm that would be a cool feature, where you could assign particles to be negative or positive. Hence positive particles would always repel each other but would be attracted to a negative particle. :wink:
Oh, I thought that particles get assigned something like this already. Sort of like a force that either positive or negative..
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sf_dude
Oh, I thought that particles get assigned something like this already. Sort of like a force that either positive or negative..

Yes, one can set the “charge” using the property POP.
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andrewlowell
This might be overkill but I like to use actual point-RBD's in a dynamics simulation. This ensures that they will hit and deflect from one-another.

If they are flying around randomly you can treat them a lot like particles and use noise feilds in various forces like gravity / uniform / and wind.

Another thing is that if you want to put them in a container make sure the volume based collision is turned off. This turns it into a thin-wall collision and works much better for that kind of stuff as long as the substeps are turned up.
Ok, so if I understand correctly, I would use Copy node to populate the “particles” and then apply force to them instead of using POP Network ?
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in a dop network you could use the point or fracture RBD
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Check out Digital Tutors Intro to Houdini 9. There's a good tutorial on particles. :idea:
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