"Wobbling gear" reduction?

[asid61]

Has anybody every heard of this type of gear transmission:
https://www.youtube.com/watch?v=Nhy4hXdYCfw
It uses a wobbling ring with pins on it and what appears to be cycloidal teeth on the gears. Does anybody have any efficiency calculations or even guesses? It seems like a neat way to get a large reduction in a thin space.

[Ty Tremblay]

What would this have over a harmonic drive?

[asid61]

Originally Posted by Ty Tremblay

What would this have over a harmonic drive?

Harmonic drives, to my understanding, rely on mechanical warping to function properly, and seem very tricky to design. This relies on completely different mechanisms to work and seems far easier to design and manufacture. I would not be confident making a harmonic drive, but I could see myself making this on a 2-axis CNC, manual mill, and lathe.

[cbale2000]

Originally Posted by Ty Tremblay

What would this have over a harmonic drive?

Well, it looks like it would be a lot easier to make for one. Might be more durable too.

[BBray_T1296]

There was a thread on here about Cycloidal Gearboxes. this is virtually the same thing, but with different geometry.

[Ty Tremblay]

Originally Posted by asid61

Harmonic drives, to my understanding, rely on mechanical warping to function properly, and seem very tricky to design. This relies on completely different mechanisms to work and seems far easier to design and manufacture. I would not be confident making a harmonic drive, but I could see myself making this on a 2-axis CNC, manual mill, and lathe.

You do need a deformable gear in a harmonic drive, but they can be 3D printed.

(That channel actually has a lot of interesting gear trains, like this one.)

I would seriously balk at attempting to calculate the tooth profile of those non-wobbling gears.

[asid61]

Originally Posted by Ty Tremblay

You do need a deformable gear in a harmonic drive, but they can be 3D printed.

(That channel actually has a lot of interesting gear trains, like this one.)

I would seriously balk at attempting to calculate the tooth profile of those non-wobbling gears.

For FRC use I balk at using 3D printing both due to the efficiency loss as well as low strength. I've seen that channel and I definitely has interesting stuff on it.
Calculating the tooth profile should just be plugging in an equation, and I can always just ask the owner of the channel for them.
I was thinking of cycloidal gearboxes, but this has the advantage of not being eccentric, and thus you only need one wobble plate to counterbalance itself.