[sixtyj]

For roller coasters there is a software for simulation. It is imho similar situation compared with balls in your Marble Fountain

https://www.nolimitscoaster.com/

First, I thought about Ansys or CATIA software but I couldn’t find any module specialized for simulation of balls.

But I think that people from those companies could help as well and participate in simulation as an interesting usecase. (These software are expensive for personal projects.)

[djmips]

Well except for this is SIM only whereas the OP (WillMor) is making them for real with a 3D printer!

[sixtyj]

My point was that these software could help to find weak parts in trajectory - so instead of trying to figure it out by looking where balls are too quick to fall from the ride - you can simulate it. I saw real tramway simulation done in Ansys.

[stavros]

I think the physics are different, a ball is basically a car without a differential, so it's going to behave differently on the tracks. I'd imagine the ball is harder to simulate because of that.

[bazzargh]

One of the results for hilbert curve marble tracks, mentioned elsewhere in the thread, was a video showing how to make one in blender, which has a physics engine so it can simulate it pretty well.

https://www.youtube.com/watch?v=8YeXyUNCnhM

I'd imagine that the 3d-printable models could be imported into blender, so it's 'just' adding balls and motion to the lift.

[sixtyj]

You can simulate everything in these professional (and expensive) software.

https://ansyshelp.ansys.com/public/account/secured?returnurl...

But for hobby purposes I would suggest to contact some university, they have such software, and they could find simulation of balls motion at marble fountain interesting for research (and educational) purposes.