Sum of torque

[EOW]

labo frame reference: when you are in the laboratory and you look at the device turn, http://en.wikipedia.org/wiki/Laboratory_frame_of_reference

support frame reference: when you are in the support and you look at the disk

maybe I can use a massless roller chain like that it's easy to straigth the chain.

[EOW]

If I use a massless roller chain with friction, I can roll up the chain around the red disk, friction will slow down the red disk (in the support frame reference) = accelerate the red disk in the lab frame reference. The red disk has a mass.

Cycle:

1/ The red disk don't turn in the lab frame reference, launch the support at w. The roller chain is all around the support. The energy needed is the energy for turn the support at w
2/ Roll up the chain around the red disk, at final the roller chain is all around the red disk, not on the support
3/ Slow down all the support. The energy recover is the energy from the support and the energy from the red disk.
Repeat

[dieter]

I think I am beginning to understand slooowly  .  In the next weeks I won't have much time to hang around in forums  . This was interesting. Maybe you should build one of these devices?
What I usually do is:
1 have the idea
2 draw it in 2D
3 simulate it in 3D in the Computer (here I often discover flaws in my thinking!)
I'm using Blitz3D, but any flexible 3D engine will do. Making use of an attached physics engine may be useful, maybe not always.
4 make a crude model, eg. of wood.


Kind Regards

[EOW]

Thanks for the software, I will simulate. It's difficult to start with Blitz3d ?

Regards

[EOW]

I think it's better with a straigth roller chain to roll up on the red disk (the chain turns at w). Like (in theory) the roller chain has no mass there is only the friction that need a force. Like there is only one disk maybe it gives a force to the support, imagine the forces is like the first image, the support receives a counterclockwise torque but in this case I can place the red disk like in the second image. So, I think there is no force on the support. But there is friction and the red disk is accelerating.