I'm adding moveable eyes to one of my puppets and I've come up with the following design concept for the mechanism.  I haven't found many movable eye tutorials so I don't know if this is how it's typically done or not, but it seems logical.  The few tutorials I have looked at have either only moved left/right, are electronic, or don't appear to be self-centering.  It seems to me that if they aren't self-centering they would be very difficult to manually center and would drift upward due to the weight of the rods.  I thought I'd post the concept here and see what others thought of it before I commit to building it.  Is this a fairly normal way of going about making moving eyes or have I over-complicated it or perhaps overlooked anything important?



Also on the same subject, does anyone know what kind of mechanism Wembley's eyes in Fraggle Rock use?

I think you are on the right track. Your plate may need to be larger and have holes in it the size of the eye socket. You may have more luck with the springs attaching to the #4 rods or closer to the end where  your finger loop is on #3. Thus the reason for the plate being larger so you can attach differently.

I am pretty sure that by the time Fraggle Rock was made Henson was using servos for eye movement.

Looking good to me. From what I have seen in tutorials and from experiments I have done, the eyeballs rotate on pins for sideways movement, and that assembly in turn goes on a gimble setup for up and down movement, and rods or wires attach at the back of the eyeball to move in all directions, whether with rods, wires or servos. BUT, I have never seen the spring setup you propose. I think it is a great idea. 10 points for the thought you have put into it and drawing it up. Let us know how you get on with it. I personally am not  coordinated enough to use  the mechanisms I have tried, but I do indeed like the idea and would like to give it some  more effort in the future. Keep us posted.

This looks like an interesting build... look forward to seeing it in action!

Daniel