I’ve got a basic functioning conveyor belt working. I suppose it’s more a series of chutes with a mechanical arm that pushes objects along, but it works for my purposes. 

I created a ‘tread’ object that will animate and push objects along the belt, then created two invisible objects, one at the start point of the stretch of conveyor, and one at the end. I use these points to animate the tread:

At the end of each stretch of track there is an invisible object that looks for a collision with any object pushed along the conveyor belt. When a collision occurs, the object being pushed along the conveyor is moved to another point in the scene, to simulate it going thru a tunnel. This just makes it easier to get the object around a corner, and I could use this to spawn a different object, simulating a transformation. Code on invisible object:

I’m excited I got this working, as it opens up all kinds of factory and Rube Goldberg-ish possibilites.

Sketches: