If the 2-stage oscillator is supposed to be OU...

[Cloxxki]

I made a simple sketch for myself to explain what the simple pendulum usually does. It swing back and forth, but never higher up than it was initially released from.

If the 2nd stage, the mounting point of the simple pendulum being allowed to come down under the tension in the rod/wire, indeed bears an OU potential...how hard can it be to use the potential to get the weight to swing back up to a higher extreme position?

- Let the 2nd stage drive a fan that start blowing a nice back draft just as the weight starts its ascend. 
- The mounting point could be attached from a strong spring, which only extends at a high tension. It extends a bit and then gives back most all the OU energy, pull the weight up higher, right?
- The mounting point could shift a bit sideways at the right moment, from energy stored in a spring. Sideway movement on a pendulums mounting point can be enough to make it loop all the way around, right?

In all cases I can think up, I'm pretty sure the energy taken out of the simple pendulum (most logically in the form of height), will be the same or less than what can be put back. We need it all back to reach our starting height. And if we somehow manage a height gain of the weight, but we can't let it swing back to the exact starting situation, plus a raised mounting point or shortened rod/wire, we still have nothing.

In stead of looking for ways to loop the 2-stage oscillator, should we not also explore ways to simply get gain in the primary pendulum itself? 1mm of sustainable gain with a 1000mm pendulum rod/wire length, that would impress me quite a bit.

Thanks for reading and thinking along,

J

[tagor]

If the 2nd stage, the mounting point of the simple pendulum being allowed to come down under the tension in the rod/wire, indeed bears an OU potential...how hard can it be to use the potential to get the weight to swing back up to a higher extreme position?

it is very easy to test !!

[Cloxxki]

Well, that the pendulum doesn't violently swing out of control, that has been well established. It maintains height at best, in a hypotheticaly frictionless environment. Some deflection is (or substituted) due to the rotation of the earth. Very maybe this effect could be harvested if at all additional, but really its minute.
Those who proclaim the 2-stage oscillator is OU, should have a pretty easy time creating a pendulum that gains height with each swing. How can work be done by a pendulum, if it can't even sustain itself?