# Problem with Particle Interaction

Note: I have searched through the forums and tutorials and am still not getting the answers I need

I have been attempting to use Particle Interaction with my animation and am not having good results. My animation consists of a tunnel that has a slope at one end. I would like to get some small rocks (about 5-7) to roll down this slope and come to a rest at the bottom.

I can get close with Deflection but I can’t get the Particles to come to a stop at the bottom. How can I achieve this?

Have you tried softbodies? Do a search for either softbodies or rigid bodies. I remember someone making a really good video using softbodies to achieve rigid bodies. Sounds like an oxymoron, doesn’t it?

https://blenderartists.org/forum/viewtopic.php?t=42225&highlight=rigid+bodies

“You could get a good Rigid zBody effect by using Blender’s soft bodies. You’d have to turn off “Use Goal” and then turn on “Stiff Quads” and set E-Spring to a high value (like .999 I think is the highest you can go to) then set the floor to do softbody colisions, and it should simulate your effects the way you want the to be, though you might have to mess around with the settings…” - Here’s one idea from Ongnissim.

edit Just tried it out and it works well as far as I have tried it.

If you are not doing too many particles it mite be worth while just doing it with normal keyframes…

Otherwise remeber to use stiiff quads. Also you need to remeber that the object rigity is from edges. That is a icosphere is like a hollow ball and can dent if the E damp isn’t zero… cus there are no edges through the center

Using a stiffness of 0.999 is very slow --your better off with internal edges and vertices and a stiffness of 0.95 or even 0.9. based on my experances. But then putting edges through the center is a pain.

delt0r

should you subdivide something like a cube then for your softbody?