How to get particles to stick to mesh and also get de-sticked by another mesh

[zef]

Hey guys,

I've been wracking my brain with this one for days now and I think I need help.

I'm trying to simulate some particles falling into a rotating mesh and having some of them stick to the face of the mesh, only to be scrapped off later on by another mesh. 
I've attached a couple of images and a video with how the animation is supposed to go and how the tyflow event looks so far.

The particles need to drop from the top, fill up the cup of the A mesh, which then starts rotating counterclockwise, the particles then drop down BUT some of them need to stick to the face of the mesh, only to be later scrapped off by the B mesh which also rotates (clockwise). 
The main issue I'm facing is making the particles stick to the face of the rotating A mesh, when the cup holding the particles ends up on the bottom side.

Would really appreciate any help to point me in the right direction. I'm also willing to pay someone of an hour of their time, if they know for sure they can make this effect happen as described.

Thank you!

[d4rk3lf]

That shouldn't be hard.

First of all, don't use Particle Physics and PhysX in the same event. They are 2 different solvers.
If your particles are in sphere like shape, particle physics should be all you need, and you can use Physx if your particles are not spherical (or uneven.. like sticks)... Physx is slower btw.

In your case I would start similarly as you, just with using particle physics and collision operator.
Then I would make some mesh on top of the A object (simple cylinder should be fine in this case), covering the parts where you want some particles to be left.
I would then use "surface test" operator referencing that cylinder (volume inside option), and then would lead it to new event where I would just have object bind (referencing object A).
So now, in essence, every particles that falls inside cylinder volume will be stuck and proceed rotating, and they will be in the second event.

Now in the second event add another Surface test (referencing object B), and this time you can use distance option, and then lead that to third event, so you send every particle that is touching the object B in the third event.

Now in the third event, you can do whatever you want with them.
You can delete them... or they can proceed colliding with object A and B if you add collision operator (and fall, if you add force operator with gravity)

Hope my explanation is clear enough.