All this discussion is about reducing external resistance to the moving machine. Minimizing parasitic losses is exactly what advanced engineering aims to do to maximize efficiency.
Batteries want to maximize energy storage return and motion based energy storage systems like this aim do the same...both by reducing parasitic loss. Heat, friction, gravity, etc all contribute to the parasitic losses such that the input energy can never be fully returned.
Therefore, there is no such think as 100% perpetual. Even light (photons) exert external force which drains energy from the system by resistance.
Isaac Newton stated that “An object in motion will remain in motion unless acted upon by an external force.” That is true, but everything in the Universe is an external force acting upon any object moving and thereby slowly resisting its motion...and eventually causing it to cease moving.
There is no such thing as perpetual motion because there is no such thing as zero resistance in the known universe.
