Need help with very simple fracture/explosion/RBD solver

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Hello!

I'm a longtime blender user finally trying houdini. I have never felt more stupid. I have a simple conveyor belt animation with 6 blocks that I would like to fracture/explode as they reach the middle point of these two posts. In blender, I would simply add a force above the two posts and animate its power to explode the blocks as they pass the threshhold. In houdini... I am totally lost, even after spending all day watching RBD tutorials. I am using a simple RBD setup, but cannot for the life of me find a way to add a simple force. I did try double clicking into the solver to the forces level and tried all the POP forces... none of them gave me the result I was looking for. I also looked into going into the dopnet but can't edit that with my indie license. Many of the youtube tutorials I watched made a rigid body sim from scratch... should I just start over and avoid RBD? I'm totally lost and undereducated.

I would really appreciate any help! Thank you!!

img]https://imgur.com/a/aFOvBfQ [imgur.com]

Attachments:
houdini2.mp4 (2.7 MB)

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Here's an example. When the columns move between the 2 posts, it deletes the outer constraints to let the pieces fly in all directions with an initial force applied to the pieces.
To do that it first needs to find the pieces attached to the constraints' anchor points as the constraints themselves don't actually move during the sim.
It uses 2 wrangles in a sop solver which allows you to access both the constraint geometry and the rbd pieces geo, one to delete the constraints - it needs access to the rbd pieces as mentioned above - and the other simply adds a random force attrib to the rbd pieces.

Attachments:
ControlledForce.hip (1.1 MB)

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