Sjack Abeling Gravity Wheel VIRTUAL replications and models

[LarryC]

Centrifugal force is unlikely to be the source of the free energy.

A mathematician will tell you there is no such thing as centrifugal force: what you perceive as centrifugal force is the force needed to provide a acceleration/deceleration to alter the momentum of the object to change it's direction of motion.

Or to put it a simpler way, the centrifugal force is energy you put in somewhere else and is stored as momentum, until it is returned. (Like a spring, except without fatigue and losses to heat.)

The good news is, just like the guides and slots, as long as you can determine the actual path of the weights, you can ignore the  actual causes of the object following that path, and so calculate still calculate the torques supplied/required  - a force moving due to "centrifugal force" (or lack of centripetal acceleration as a mathematician would say)

Then can you explain why most trap throwing equipment uses a accumulated CF force sling method. The trap is set in the middle when the arm is at rest, then thrown out when the arm is at center forward.

You could block the end, then put the trap on the end and stop it at a point to let it fly off at a tangent, but it doesn't go as far.

Better example is a test centrifuge, except put the chair at midpoint on a rail that lets it slide out to the edge. Bring it up to an rpm that a subject could handle if the chair was at the outer position. Release the chair and after the impact scrape the subject off the chair. Any volunteers?

It is the accumulated acceleration caused by CF from middle to edge that makes the impact much higher then just the CF force at the edge.

Regards, Larry   

[stgpcm]

Springs suck. They operate by deforming under stress. That deformation wastes some of the energy put in as heat When compressing the spring you increase the reaction forces in the components driving that compression, increasing friction.

[stgpcm]

Then can you explain why most trap throwing equipment uses a accumulated CF force sling method. The trap is set in the middle when the arm is at rest, then thrown out when the arm is at center forward.

1. slingshot - moving the pivot point gives you some lovely mechanical advantage.
2. spin, that design puts a lovely spin on the clay, letting it frisbee.
3. by putting a block  at the end you're either shortening the arm, (by the radius of the disc), or adding extra mass at the arm away from the pivot, soaking more energy to accelerate it
4. by putting a trap in to stop the arm, you're prematurely stopped it's operation - there was energy left in that spring.

Better example is a test centrifuge, except put the chair at midpoint on a rail that lets it slide out to the edge. Bring it up to an rpm that a subject could handle if the chair was at the outer position. Release the chair and after the impact scrape the subject off the chair. Any volunteers?

you certainly would go splat - all the acceleration you could take in a quater turn has just been delivered to you an instant. That hasn't change the total amount of acceleration, just how quickly it was delivered

It is the accumulated acceleration caused by CF from middle to edge that makes the impact much higher then just the CF force at the edge.

Most of us call accumulated acceleration "momentum", and yes, by allowing the chair to slide, some of the force is turned into angular momentum, but the rest into linear. at the moment you hit the rim all of the linear momentum is delivered as an impulse.

A half pound weight can sit on top of a tomato all day. If you lift it 5 meters above the tomato, then release, it accumulates acceleration (or would you prefer me to say it accumulates gravity?) which it then imparts to the tomato after about a second.

Regards, Larry
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[stgpcm]

In a end of arm scenario, the centripetal acceleration is provided by the end stop, which applies the force perpendicular to the circular motion, so it is all dispersed as strain - in effect the only time 100% of the torque is being applied to accelerate the disk is at the moment it is released.  So for a 90 degree swing you gain about 1/root(2) of the work you put in when you cocked the arm.

In the thrower, no centripetal force is applied, so you gain all  the work you put in when you cocked the arm. Further, as you pointed out, the disk leaves  thrower releases at around 135 degrees, so for the same cocking torque you can put an extra 50% of work into the spring. Now, in reality, the  speed of the disk from the thrower is going to be less than the theoretical 3/root(2) times the tangential arm, but with a well designed system it should get close.

[LarryC]

In a end of arm scenario, the centripetal acceleration is provided by the end stop, which applies the force perpendicular to the circular motion, so it is all dispersed as strain - in effect the only time 100% of the torque is being applied to accelerate the disk is at the moment it is released.  So for a 90 degree swing you gain about 1/root(2) of the work you put in when you cocked the arm.

In the thrower, no centripetal force is applied, so you gain all  the work you put in when you cocked the arm. Further, as you pointed out, the disk leaves  thrower releases at around 135 degrees, so for the same cocking torque you can put an extra 50% of work into the spring. Now, in reality, the  speed of the disk from the thrower is going to be less than the theoretical 3/root(2) times the tangential arm, but with a well designed system it should get close.

Actually, the equipment in both of my cases would swing 135 degrees. For the tangent thrower it could still have a extended edge to cause a rotation. It still would not throw further than the accumulated acceleration CF sling version. 

BTW, your root(2) notation is unusual, did you mean sqrt of 2 or an array named root where you wish to divide by the value of the second member in the array?

Regards, Larry