I wanted to build an animatronic hand puppet. The big challenge I faced was trying to sync up the movement with the speech. I still have this in storage and one of these days I will bring it back to life. I think it still has potential even after all these years. I'm sharing my results here because I think the platform is pretty good for animating despite the challenges I had achieving my end goal.
This is an early test jig for the mechanical arm that drives the puppet. What I discovered here was that the original hobby servos I had were not powerful enough. I swapped these out for ones that had more torque.
Here is a video of a early mechanical test
To join all the servos to gether I cut this metal bracket out of a sheet of 3mil aluminium. The paddles on the top/bottom of the servos drive the upper/lower jaws of the puppet. They are cut from 5mil. acrylic. This gives them some flex (but not much). I hot-glued the paddles directly to the body of the servo motors. This approach sorta works. The glue is not that strong but it holds well enough. If the upper/lower jaw servos are over-rotated the paddles will pop-off. You could think of this as a "saftey feature".
Here it is doing a simple "laugh movement" test
The big hurdle for me with this project was trying to come up with a way to sync the movement and the audio. It seems possible but I lost some steam trying to make that work. If you know of any similar projects or have experience with this type of thing any advice is appreciated!