Smelter and Coolio both drew my attention to this paper model of a push up character on a Japanese karakuri website.
Unfortunately it is impossible to tell from the picture just how it is driven. One thing is for certain though, the drive is through the feet, not the arms just as in my proposed model.
This plastic, wind up model which I found on the Hawkin's website has powered arms.
Master automata maker Paul Spooner produced this delightful model some years ago, again driven via the feet.
This time a circular cam with a slot round its circumference pulls on a string as it is turned, in turn this pulls the feet and lifts the body.
…and hydraulics power and both beyond the scope of paper projects. So far.
Cam power, however, is not as per this model that I produced for a company some years ago which appears to be no longer in print.
So we come back to the design I'm working on now. It is fascinating to see how your approach to a similar problem changes over the years.