Recover energy from gravity

[rc4]

There is no water. Take last Algodoo scene. No friction from air. No gravity.

The ball can be not compressible in fact. The system move alone (no axis) and sum of energy increase, without never stop. Even there is friction at 0.5, the friction must lost energy but in fact with friction the system win energy. Friction change the sum of forces. I take frequency at 12000 Hz, results don't change from 4800 to 12000 Hz. At start I added only an angular velocity.

I think friction act on center of gravity of small ball (2), and act on piece (1), there are not same center of gravity and radius are not the same. So the torque is not the same.

If you change mass of one part of the system this change the efficiency.

Without linear velocity, the system lost energy.

[rc4]

I tested with bigger dimensions. The difference of energy is bigger. I choose parameters for have small forces in the same range than previous test.

[rc4]

I think I understood how energy is won.

Image 1/ Average power measure by Algodoo is 10.2 W
Image 2/ Average angular velocity is 0.7044 rd/s
Image 3/ Average force is 0.0647 N (only a dy for compute only axis Y, relative to system at start)
Image 4/ A torque exist on Object2, the power from torque is 11.2 W
Image 5/ In the contrary Object1 moves only 0.686 m, so the power is 0.686 * 0.0647 = 0.04 W

Image6/ The system, scale

Like I measure average of force from -15° to 15°, I need to correct value of 11.2 W, this is (1+cos(85))/2*11.2 = 11 W it's very close to 10.2 W.

[rc4]

I study this new case. More stable and I think it's the different trajectories that give energy. Object2 (red and orange colors) turn, but not Object1 that is more in translation trajectory like image showing.

Object 2 receive a torque, the radius come into equation, it's 0.026 m. In the contrary, Object1 move only in translation for a big part, and the radius of rotation is at 0.0001 m. Forces from torque are sum of T and N. For compute, take Power = Torque * angular velocity = 22 N * 0.026 * 18.4 = 10.5 W, it's near Algodoo find (Algodoo don't compute friction).

For the sum of forces on each center of gravity I need to compute the direction and for Object 1 it's logical the force works.

On Object1, forces from Object2 pass by its center of gravity and like it is less than 1/10 of the trajectory of Object2, the works it's lower (1/10).

[FatBird]

Wow, this is so CLEAR & Easy to make, I'm sure everybody here will make one RIGHT AWAY.  LOL


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