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I imagined this device and I don't understand where is the error. I posted here because it's a simple mechanical device, I have trouble with the sum of torque. The potential energy must be constant. I think I forgot a torque, if you see where ?

A torus turns counterclockwise around the center C1. C1 is fixed to the ground. The center C2 is fixed to the torus and a square object can turn around C2. I put inside the square Object a lot of small balls where there isn't the torus. Each ball is attracked by a spring (not drawn). The springs attrack balls like gravity can do, but Gravity1 is higher than Gravity2. I called it gravity but it's not a gravity it's just for have a pressure with balls like water can do in a recipient. The springs are attached on the green points, and the green points are on the square Object not on the torus. I drawn all forces I see and I can have the sum of forces on the center C2 like the yellow force so the torus don't receive a torque from C2. In the contrary the square Object with balls inside receives a net torque on it. The square Object will turn counterclockwise BUT I turn the torus counterclockwise more and more in the time for have the same angular velocity for the square Object and the torus. The angular velocity of the torus "follows" the angular velocity of the square Object for keep constant the angle. I need an energy for accelerate the torus but this energy can be recover later. In the contrary, I don't give an energy for rotate the square Object but with time it turns more and more, and the potential energy seems to increase. I need to accelerate more and more the torus but I don't think the problem come from this particulary. What's wrong in this device ?

The device:

The forces:

Where the balls are inside the square object:

Several positions of the device, for show the angle:

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# Sum of torque

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