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[Jona]

Hi lakes

I agree that Stepper motors are a good option, though to show OU, you would like to get rid of all external power sources.

[hydrocontrol]

Hi All,
  In my 'primitive' and 'not exact' replication I have noticed a few things.

1. The effect appears to be real. There is a very apparent syncing effect that 'as it happens' appears to keep the rotor at a steady speed for at least a couple of seconds. I still have to 'learn' how to do video but mine would still pale in comparison to this one already posted. This effect can best be seen in
CLaNZeR  video CLaNZeRSLatch4.wmv at http://www.overunity.org.uk/

2. Is going to be extremely hard with this setup to find the 'right' combination of magnet strength, location, friction, bearings, mass of rotor, mass of stator, etc. I have only two lengths of rotor magnets to play with .5 and .75 inches. I think Al's are somewhere in between. I would hazard to guess that even Al would have a hard time making a working second one.

3. Is not going to be 'slap it together' and it will work system. :'(  I am not saying that what Al did was a fluke and not reproducible. I am saying that it is going to be a 'real bear' to get one working so it may take weeks-months of playing to get another one running. Of course someone may have one running tomorrow  Doubt that it will be me  :'(

[lumen]

@Charlie_v

I should have shown the stator tachometer. It is not a simple coil detecting the magnetic field, it is rotary device like a small generator that generates a voltage from rotational speed.
The specs are 7v per 1000 RPM.
The wave you see is actually the stator speeding up and slowing down as it pases each amgnet on the rotor.

[xumed]

@Charlie_v

I should have shown the stator tachometer. It is not a simple coil detecting the magnetic field, it is rotary device like a small generator that generates a voltage from rotational speed.
The specs are 7v per 1000 RPM.
The wave you see is actually the stator speeding up and slowing down as it pases each amgnet on the rotor.

This slowing and speeding up is because of the slow/fast parts of the cycle on the stators as clearly shown by ZeroFossilFuel on youtube http://www.youtube.com/watch?v=EHy_OeS8qVE

Most people dislike his replica but He is very knowledgable and his replica is only intended to explain some of the effects seen.

Good job Lumen on your observations and methodology

[Charlie_V]

Oh ok, can you give me the model number and manufacturer of the tach, I'd like to look those up, they sound pretty neat. 

Thanks,
Charlie

[RunningBare]

This slowing and speeding up is because of the slow/fast parts of the cycle on the stators as clearly shown by ZeroFossilFuel on youtube http://www.youtube.com/watch?v=EHy_OeS8qVE

Most people dislike his replica but He is very knowledgable and his replica is only intended to explain some of the effects seen.

Good job Lumen on your observations and methodology

Cube magnets and diametrically magnetized cylinder magnets have considerably different field characteristics.

[sveinutne]

@Charlie_v

I should have shown the stator tachometer. It is not a simple coil detecting the magnetic field, it is rotary device like a small generator that generates a voltage from rotational speed.
The specs are 7v per 1000 RPM.
The wave you see is actually the stator speeding up and slowing down as it pases each amgnet on the rotor.

@lumen

I have tried to find the relative movements between the rotor magnets and the stator magnets, and a lot of people have been speculating and making sim models about this, but with your equipment and setup you might be the first to really describe the position of the magnets.
Great work.
Svein
 

[ken_nyus]

Is there a problem in reconciling Lumen's measurements of the movement of the stator (accelerating-decelerating) with Al's measurment of the pulsing field of the stator measured with a Rogowski coil and shown here as a pretty straightline sawtooth pattern:

http://www.ospmm.com/whipmag/3Ax8_s2.jpg

(from www.ospmm.com/whipmag)

I don't know enough to make a good judgement here, but maybe someone who does can comment on the two compared?

[Craigy]

The operation of this motor is reliant on the the stator being able to vary its speed. The acceleration, and deceleration must be of a controlled nature so that the overall stator interaction is aysmetrical and we get a gain. If the stator and rotor were locked or geared together you would not get a gain. If you could gear it together but with a 30 degree null zone on the gearing this would allow the decelerations and accelerations so vital to get through the rotor field with a gain. In Al?s motor it appears he had the balance just right, and the inertia was in just the right amounts.

Therefore if the stator is too light, the stator will go too fast in the acelerations and slam into the wall of repulsion, if the stator is too heavy it won?t react fast enough and  it will slam into the wall of attraction. The trick is getting a dribble of one or the other.

In this femm graphical representation of the interacting fields we need to stay in the blue zones to escape with energy
this was done by Greg L. .

[hydrocontrol]

Craigy wrote :

The operation of this motor is reliant on the the stator being able to vary its speed. The acceleration, and deceleration must be of a controlled nature so that the overall stator interaction is aysmetrical and we get a gain. If the stator and rotor were locked or geared together you would not get a gain. If you could gear it together but with a 30 degree null zone on the gearing this would allow the decelerations and accelerations so vital to get through the rotor field with a gain. In Al?s motor it appears he had the balance just right, and the inertia was in just the right amounts.

Therefore if the stator is too light, the stator will go too fast in the acelerations and slam into the wall of repulsion, if the stator is too heavy it won?t react fast enough and  it will slam into the wall of attraction. The trick is getting a dribble of one or the other.

This pretty much backs up what I have found in playing with my setup and what I wrote above.

Hydrocontrol wrote:

2. Is going to be extremely hard with this setup to find the 'right' combination of magnet strength, location, friction, bearings, mass of rotor, mass of stator, etc. I have only two lengths of rotor magnets to play with .5 and .75 inches. I think Al's are somewhere in between. I would hazard to guess that even Al would have a hard time making a working second one.

[CLaNZeR]

The operation of this motor is reliant on the the stator being able to vary its speed. The acceleration, and deceleration must be of a controlled nature so that the overall stator interaction is aysmetrical and we get a gain. If the stator and rotor were locked or geared together you would not get a gain. If you could gear it together but with a 30 degree null zone on the gearing this would allow the decelerations and accelerations so vital to get through the rotor field with a gain. In Al?s motor it appears he had the balance just right, and the inertia was in just the right amounts.

Therefore if the stator is too light, the stator will go too fast in the acelerations and slam into the wall of repulsion, if the stator is too heavy it won?t react fast enough and  it will slam into the wall of attraction. The trick is getting a dribble of one or the other.

Well I have the Rotor and sizes now as close as I can get, but the weight now is different. Might have to shave some of the Rotor off.
Anyone remember the exact weight of AL's Rotor again?

(http://www.overunity.org.uk/ocpm/compare1.jpg)

(http://www.overunity.org.uk/ocpm/final2.jpg)

Cheers

Sean.

[ken_nyus]

From my notes, Al's rotor was 258 grams.

[geodan]

Sweet! you guys rock!!


@ All - not to re state the obvious, but t would appear to me,  that through a long process of experimentation and tinkering with what he had on hand Al hit upon just the right recipe.  From a replicators point of view I'm wondering if the information and drawings that we have include enough specific detail about the original rig assembly and components, (bearings, materials, magnets) and their physical / electrical properties for replication or if they represent an approximation of how it cold be replicated... I'm wondering if some of the finer details might not have been lost in translation... I'm thinking that everyone is sooting at a pretty small bullseye.. any thoughts on that?

A ruler in the Al's frame would have helped tremendously... does anyone recognize the DVD?

[Smit80]

That would be Behind Enemy Lines ...

Found here:

http://www.hotmoviesale.com/dvds/6659/1/Behind-Enemy-Lines.jpg

[blue_energy]

There is this by 'Just Maybe' on the Whipmag Development discussion:

If anyone is interested in evaluating the Kinetic energy of the WhipMag Rotor at various speeds you can use this formula based on a weight of 0.258 kg and a radius of 0.073m.

0.000344*(rpm/9.55)^2

It is not exact as it assumes even density of the rotor (its not, due to the magnets) and the numbers are rounded somewhat

(worked out from the following)

Ke= 0.5*I*w^2

I= Moment of Inertia = 0.5*.258*.073*.073= .000687441
(Slight difference from Pcstru, so please check it)

w=Angular velocity in radians= rpm/60*2pi

so Ke for 400 rpm= .5*.000687441*(400/60*2pi)^2 = 0.603091 Joules

Simplified and rounded =0.000344*(400/9.55)^2= 0.603492 Joules

...so 258 grams seems somewhat confirmed.