Algodoo

Yes, it truly is a very interesting concept. I searched on the Web too but wasn't able to find any reference to it at all. I wonder if anyone uses this in real life, and if not, then why not. I've seen inclined roller conveyors used for loading and unloading trucks but the rollers were configured laterally rather than longitudinally like this one in your scene. And, of course, there must be a lot of them when they are oriented laterally along the length of the conveyor. Also, they were not powered.

BTW - I'm experimenting with a pair of rollers that have a 3D look to them that you may be interested in using to enhance this scene. If it looks and works like I hope it will, then they could be used to give a more true-to-life image of how such rollers would actually look, rather than that stationary bar with the moving texture that you used in the scene. We shall see!

I apologize for my being so verbose. That's just how I am.

Sounds like a very interesting concept

Thanks guys. I think the physics of the roller ramp is similar to car drifting. I looked up "physics of car drifting", but don't see any statements mentioning the fact that the process is somewhat self regulating in that sideways friction preventing a spin out increases with sideways speed. In the roller ramp, for a fixed roller speed, the ramp apparent friction is proportional to the box speed.

I really don't see how this would work in real life. As I understand it, you would be getting rid of static friction, but dynamic friction should be pretty much the same, so the block would be subject to an acceleration depending on the angle of the ramp (like any regular ramp with friction). At least on paper, I think those are the only forces at play, other than the canceled out roller forces etc.
Now if the rollers were slightly more separate on one of the ends, that would definitely create a force, but still not self-regulating as you describe?

Friction force is µ*N in the direction of relative motion, not in all directions. I'm thinking that the apparent coefficient of friction perpendicular to the direction of motion is zero, until you start moving in that direction, in which case the direction of motion changes.

Hmm, now I see what you mean. by applying a lateral relative motion with the rollers, you "deflect" the friction vector and thus reduce the component parallel to the movement. but if the box moves faster, the vector will rotate as the relative velocity of the box will be higher in the movement direction, and the "braking force" increases. Is that right?

Yes, that's what I think happens. Nice concise explanation. Now all we need is someone with a 3D printer to verify the physics.

Not sure if you can use this but I think it would be really cool if you can make a box slide down it toward the viewer!.

3D Rollers

I guess I qualify. I was considering doing it, using a couple of smooth 8mm rods as the rollers. or maybe piping of some sort. i'll see what i can come up with