.....at : https://au.bestreviews.guide/perpetual-motion-toys
.....including rolling-jumping ball...a kind of (see...) Stevinus "simplified"?
.....playing gravity field and ???
Al_ex
Well it looks very nice 8)
But the 1st instruction tells the secret:
Quote1.You need put battery in the back of the round platform.
Hi Truesearch !
A spring can play as a "mechanical battery" charging and discharging a variable arm pendulum .
If you take a look at : https://i.stack.imgur.com/y8N13.png (https://i.stack.imgur.com/y8N13.png)
.....we can play gravity and conservation of angular momentum with minimal spare parts ( two soft springs and a free sliding mass...as a "liniarized atom").
Al_ex