A quick post showing the arms for the tumbling acrobat model in place. There are two stops to limit rotation. The legs will fit in the place indicated, possible with a paper hinge rather than an axle. I have reduced the weights in the tube to three penny coins total weight 12g. I'm still worried that they pick up quite a bit of speed as they roll down the tube. A friend of the web site who has a plastic version of this automata says that his model has ball bearings with baffles to slow down the roll. Not sure if I can do baffles for coins but I'll give it a try.
I put together this coin tube complete with baffles which slows the coin down nicely. Might need to experiment with different angles and heights of the bump but even as is, it stops the coin crashing too hard into the end of the tube.