Author Topic: EM Drive Developments Thread 1  (Read 765629 times)

Offline JohnFornaro

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Re: EM Drive Developments
« Reply #2700 on: 10/27/2014 11:54 PM »
...  I'm simply saying that although there is a fantastical amount of great value here especially as regards Dr. Rodel's analysis to this point, this data is from a conference paper, written to gain funding.  It is not a statistically valid sample.....  And these other labs haven't put out data that we can look at.  So how then can we compare them?

I have said what I have said about Sonny's method on several occasions and the point here is to note, that this is a conference paper, with no statistically valid data, and so any comparison is doomed to mislead at best, ...  There's nothing wrong with Dr. Rodel's method so far as I can see, save that he's straining to do a real analysis of something less than real data.

You make valid points about error-bars and the paucity of data points.

However you persist in your claim that it is not 'real' data and thus fabricated.
Please stop this nonsense. Question everything by all means.

Sticking with, as I tend to do, with the best of what people write and not the worst, I think it is important to restate that the data is not being considered as fabricated by the competent analysts here.

There are not enough data points, based on what is believed by consensus to be a lousy experimental protocol, which is supported by poorly written and inconsistent theory.

I believe that Jose is teasing out what he can of substance from the data, but it is my personal opinion that he will fail to discover anything of merit, because there's simply not enough to go on, unless there is a greater sharing of information from the collectors of the data.  And that does not seem to be forthcoming.

Funding motives for research are well understood by the community.
« Last Edit: 10/27/2014 11:59 PM by JohnFornaro »
Sometimes I just flat out don't get it.

Offline JohnFornaro

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Re: EM Drive Developments
« Reply #2701 on: 10/27/2014 11:58 PM »
Please, please, keep this place honest, open, and constructive by all means.

Good job, Frob.
Sometimes I just flat out don't get it.

Offline IslandPlaya

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Re: EM Drive Developments
« Reply #2702 on: 10/28/2014 12:04 AM »
Say we had an optimised on the ground setup that produced x Newtons of thrust.
How would we translate that experiment to the ISS? Obviously it would be carried out in vacuum, but how would we measure thrust (if any?)
Let it free float and calculate acceleration? How would the experiment be constrained etc... Power supply (batteries) on the experiment or tethered for power/data?
« Last Edit: 10/28/2014 12:05 AM by IslandPlaya »

Offline Star One

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EM Drive Developments
« Reply #2703 on: 10/28/2014 12:06 AM »
Wouldn't it be better to wait until you get more experimental information from those actually working in this area, it seems like there isn't enough data out there in the public domain at the moment to form a coherent answer to your questions?

From what I can remember aren't EagleWorks supposed to be doing more work on this by now and if so it maybe the case that there will be no more data published until say next year.
« Last Edit: 10/28/2014 12:08 AM by Star One »

Offline RotoSequence

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Re: EM Drive Developments
« Reply #2704 on: 10/28/2014 12:07 AM »
Wouldn't it be better to wait until you get more experimental information from those actually working in this area, it seems like there isn't enough data out there in the public domain at the moment to form a coherent answer to your questions?

I'm with you on that. New data can't come soon enough.

Do we know when other institutions are expecting to perform their tests?
« Last Edit: 10/28/2014 12:09 AM by RotoSequence »

Offline Star One

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EM Drive Developments
« Reply #2705 on: 10/28/2014 12:10 AM »
Wouldn't it be better to wait until you get more experimental information from those actually working in this area, it seems like there isn't enough data out there in the public domain at the moment to form a coherent answer to your questions?

I'm with you on that. New data can't come soon enough.

Not to be rude but it looks like at the moment a lot of you are banging your heads on a brick wall because there isn't enough data out there to move towards either verifying or disproving these devices.

As to your other question I am sure they made some mention of testing outside of EagleWorks, can anyone verify this?
« Last Edit: 10/28/2014 12:11 AM by Star One »

Offline frobnicat

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Re: EM Drive Developments
« Reply #2706 on: 10/28/2014 12:12 AM »
The more accurate model will fit the data points more accurately.
This is the trouble, as this above is not true.  Given at least one of the half dozen contenders to explain the lab findings at Eagleworks is correct (which we don't know), there is no reason to suppose that explanation would form the basis of a calculation that is closer to the lab data than those made by other models.  When you don't know what is wrong with a model, or with the setup, or a host of other things, you cannot make these kinds of judgements.  The thing to do is certainly to withhold judgement.  There is no doubt that this above is a fallacy--an example of flawed logic--and Dr. White has deliberately exploited this sort of thing in the past in order to get funding.  I kid you not, you should never play this game.  It is wrong start to finish and has nothing to do with science.  This is rhetoric.
So you are stating that Dr White is a complete fraud and a liar?

No - no. I believe the correct choice is to discard the top 6 models and start with a clean sheet. But since we don't have 6 models, we can't throw them out.

@Dr. Rodal - Do you have current regression analysis for all the models so we will know which to discard.

@ Frobnicat - Do you have some models we can discard, or are you still awaiting new dimensions?

Discard ? I can throw in "theoretically agnostic" reasonably fitting models a dime a dozen. I think Ron makes a point about the sparse amount of "free floating" data so far, and hence the limits of fitting the data. If dr White shows "theoretically predicted values" in his presentations but has no (or refuse to communicate) equations he uses then clearly this is not science at its best. On the other hand Mc Culloch has stated an hypothesis (I don't get it) and derived and published an equation. Even if the hypothesis is false, the equation he gives scores well amongst a lot of others. Phenomenological models are not mere rhetoric. If it is predictive remains to be seen with later experiments... but at least it's published. If Mc Culloch needs to changes equation at each new experiment while standing on hypothesis but adding fudge factors, then and only then it becomes pathological science.

Sorry, just wanted to answer : yes I'm waiting for dimensions and relevant parameters to settle to do further phenomenological regressions. I don't know if it will prove decisive, but it might.

Online Rodal

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Re: EM Drive Developments
« Reply #2707 on: 10/28/2014 12:30 AM »
...
Sorry, I re-checked the code because that statement about the 7 sec didn't make sense to me and I found an error on my definition of the exponential function (I had the variable "time" instead of "t" which mean different things in my code.  I'll be back with the correct result

Offline frobnicat

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Re: EM Drive Developments
« Reply #2708 on: 10/28/2014 12:31 AM »

OK I run in my inverted torsional pendulum model in Mathematica (with coupled nonlinear equations) the decaying exponential rises of the form 

Fb(t)=80 microNewtons*(1-exp(-t/tau))

and I can firmly state that any tau < 7 sec produces a pendulum response that is negligibly different from tau =0 (an impulse response).  Any tau < 7 sec produces a response that is practically the same as an impulsive response.

That was my impression. Would you share the insides of your input/output black box ? I don't have mathematica (and wouldn't know how to use it efficiently), any chance this model of coupled nonlinear equations would be relatively easy to convert to imperative programming function (iterative form) ?

I'm thinking of a regression scheme (hill climbing or simulated annealing, or genetic algorithm if needed) to reconstruct the signal of interest Fb(t) from the observed Obs(t). This is brute force (again). Maybe inverting a transfer function would be more elegant. But I like numerical bulldozers !


Online Rodal

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Re: EM Drive Developments
« Reply #2709 on: 10/28/2014 12:36 AM »
...
Sorry, I re-checked the code because that statement about the 7 sec didn't make sense to me and I found an error on my definition of the exponential function (I had the variable "time" instead of "t" which mean different things in my code.  I'll be back with the correct result

Yes, any tau>0.2 sec is clearly discernable.

For tau ~ 1 sec the difference is unacceptable

I'll post some pictures tomorrow after I double check everything.   I need to do some work for which I get real $$$ first  :)
« Last Edit: 10/28/2014 12:38 AM by Rodal »

Offline frobnicat

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Re: EM Drive Developments
« Reply #2710 on: 10/28/2014 12:49 AM »
...
Sorry, I re-checked the code because that statement about the 7 sec didn't make sense to me and I found an error on my definition of the exponential function (I had the variable "time" instead of "t" which mean different things in my code.  I'll be back with the correct result

Yes, any tau>0.2 sec is clearly discernable.

For tau ~ 1 sec the difference is unacceptable

I'll post some pictures tomorrow after I double check everything.   I need to do some work for which I get real $$$ first  :)

All right. I'm a bit surprised then. Maybe not 7s but 2s seemed like possible to me (with eyeballs used to look at basic second order ringing oscillators).

Online Rodal

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Re: EM Drive Developments
« Reply #2711 on: 10/28/2014 12:59 AM »
...
Sorry, I re-checked the code because that statement about the 7 sec didn't make sense to me and I found an error on my definition of the exponential function (I had the variable "time" instead of "t" which mean different things in my code.  I'll be back with the correct result

Yes, any tau>0.2 sec is clearly discernable.

For tau ~ 1 sec the difference is unacceptable

I'll post some pictures tomorrow after I double check everything.   I need to do some work for which I get real $$$ first  :)

All right. I'm a bit surprised then. Maybe not 7s but 2s seemed like possible to me (with eyeballs used to look at basic second order ringing oscillators).

Well you were right about the way to attack this.   The actual response curves don't look to be the result of a rectangular pulse but rather a slower continuing rise. 

The dynamic magnification factor is much larger (and it matches a rectangular pulse) for the null force tests.

The experimental force measurements have much smaller dynamic magnification factor which is what gets affected with a longer tau.

Offline JohnFornaro

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Re: EM Drive Developments
« Reply #2712 on: 10/28/2014 01:05 AM »
John, could you please re-draw when you have a chance and the disposition 

Jose:

What with the trolls spreading their puritannical dung over your and my hysterical repartee, I have lost a great deal of interest in doing something that is no longer fun and does not pay the bills.

Still, I threw two images of the copper thing side by side and scaled them together.  Conclude what you will.

The absolute dimensions are not being revealed.  Eyeballing three point perspective lines in an attempt to scale the thing more accurately adds a lot of uncertainty to the dimensions.  Uncertainty which the experimentors could care less about removing, along with their paltry data reporting, and less than stellar protocols.

If there is something to be gained from my accurate portrayal of the proportions of the thing, then analyze frequencies and proportions.

I don't believe you're gonna find anything.

You have been a great addition to my modern lifestyle!
Sometimes I just flat out don't get it.

Offline ThinkerX

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Re: EM Drive Developments
« Reply #2713 on: 10/28/2014 01:25 AM »
I am starting to wonder if the info needed the most (predictive equations, measurements, frequencies) isn't hidden away by Non Disclosure Agreements.  Might account for the lack of later papers (after 2007) by Doctor White, and why getting other info is like pulling teeth.

There just doesn't seem to be all that much to most of these devices.  A competent machinist could probably build one in a weekend from scratch for not much more than beer money.  Oddly shaped and constructed microwave ovens basically. 

Offline zen-in

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Re: EM Drive Developments
« Reply #2714 on: 10/28/2014 01:43 AM »
This device is fictional.   No one would build a dewar this way.

Couple of random links for dewars:

Buy it now at:

http://www.cryofab.com/products/cmsh_series

http://nmrwiki.org/wiki/index.php?title=Ice_in_my_dewar!_%28Liquid_helium_transport_dewar%29

http://www.kadel.com/liquid-helium-dewars/

The oracle:

http://en.wikipedia.org/wiki/Cryogenic_storage_dewar

Gravity Probe B:

http://einstein.stanford.edu/highlights/hl_100104.html

All of those references except the last one refer to cryogen storage dewars.   A liquid Helium dewar used to test something at 4.2 K is a lot more complicated.   They are almost always customized so that the dewar can be dismantled; allowing the item to be tested to be mounted on the cold foot (a high thermal resistance material that is in contact with the liquid Helium.   It would be impossible to do that with the dewar shown below.   The inner vessel labeled as the liquid Helium vessel only has a small tube for an opening.   The device to be tested is too big to fit down that tube.  So how was it assembled?   It presents an impossible "ship in a bottle" problem.

Online Rodal

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Re: EM Drive Developments
« Reply #2715 on: 10/28/2014 02:37 AM »
John, could you please re-draw when you have a chance and the disposition 

Jose:

What with the trolls spreading their puritannical dung over your and my hysterical repartee, I have lost a great deal of interest in doing something that is no longer fun and does not pay the bills.....
Hey John could you take a look at this drawing please:  http://web.archive.org/web/20121104025749/http://www.cannae.com/proof-of-concept/design


"Figures 1 and 2 depict two halves of the QDrive cavity. The dimensions are in cms."

Figure 2 is practically solid except for the slots, which we know from NASA to be spurious (from NASA's null test).

So what I need to know is the height of the internal cavity in Fig. 1

In Fig. 1 detail A it reads "R .1000" which to me means 0.1 cm or 1 mm.  This would say that the height is 0.1 cm = 1 mm

However, if done to scale, corresponding with the dimensions shown in Fig.2  the period may be in the wrong place and the Radius on Detail A may be 1 cm and hence the height be 1 cm.

Particularly when compared to the radius labeled R.152 that in Detail A appears much smaller than the radius labeled R.1000

What do you think ?

« Last Edit: 10/28/2014 02:40 AM by Rodal »

Offline zen-in

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Re: EM Drive Developments
« Reply #2716 on: 10/28/2014 03:04 AM »
John, could you please re-draw when you have a chance and the disposition 

Jose:

What with the trolls spreading their puritannical dung over your and my hysterical repartee, I have lost a great deal of interest in doing something that is no longer fun and does not pay the bills.....
Hey John could you take a look at this drawing please:  http://web.archive.org/web/20121104025749/http://www.cannae.com/proof-of-concept/design


"Figures 1 and 2 depict two halves of the QDrive cavity. The dimensions are in cms."

Figure 2 is practically solid except for the slots, which we know from NASA to be spurious (from NASA's null test).

So what I need to know is the height of the internal cavity in Fig. 1

In Fig. 1 detail A it reads "R .1000" which to me means 0.1 cm or 1 mm.  This would say that the height is 0.1 cm = 1 mm

However, if done to scale, corresponding with the dimensions shown in Fig.2  the period may be in the wrong place and the Radius on Detail A may be 1 cm and hence the height be 1 cm.

Particularly when compared to the radius labeled R.152 that in Detail A appears much smaller than the radius labeled R.1000

What do you think ?



I am not an expert in mechanical drawing.  I think the radius marked R.1000 is meant to be a radius of 1.000 inch or whatever unit they are using.   So R.152 is a radius of .152".

Offline aero

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Re: EM Drive Developments
« Reply #2717 on: 10/28/2014 03:07 AM »
Regarding the radius of curvature .1 cm or whatever. Isn't that outside the cavity? Or is the drawing printed up side down? Not likely without deliberate deceit.

As to the base drawing attached here, what is that detailed? Is it a 3 cm by 1 cm deep torus around the outer rim of the base? If the device is designed to bounce microwaves around the corner then what would the effective depth be? Before answering, please evaluate whether or not microwaves could behave in that fashion.

If so, then Cannae's idea would be for all the end reflections to occur in the same axial direction.
« Last Edit: 10/28/2014 03:10 AM by aero »
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Offline RotoSequence

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Re: EM Drive Developments
« Reply #2718 on: 10/28/2014 05:06 AM »
Regarding the radius of curvature .1 cm or whatever. Isn't that outside the cavity? Or is the drawing printed up side down? Not likely without deliberate deceit.

As to the base drawing attached here, what is that detailed? Is it a 3 cm by 1 cm deep torus around the outer rim of the base? If the device is designed to bounce microwaves around the corner then what would the effective depth be? Before answering, please evaluate whether or not microwaves could behave in that fashion.

If so, then Cannae's idea would be for all the end reflections to occur in the same axial direction.

It looks like a standard engineering drawing, so all units should be inches, with precision to thousandths of an inch.

Offline frobnicat

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Re: EM Drive Developments
« Reply #2719 on: 10/28/2014 08:35 AM »
I am starting to wonder if the info needed the most (predictive equations, measurements, frequencies) isn't hidden away by Non Disclosure Agreements.  Might account for the lack of later papers (after 2007) by Doctor White, and why getting other info is like pulling teeth.

There just doesn't seem to be all that much to most of these devices.  A competent machinist could probably build one in a weekend from scratch for not much more than beer money.  Oddly shaped and constructed microwave ovens basically.

Building a microwave copper cavity easy yes, setting up a decent measuring apparatus ecosystem for forces and electronic signals is a bit more demanding. Maybe not beyond reach of serious DIY lab though, but at significant pocket money. Household microwave oven magnetrons are unstable, wide band, not reliably "dimmable". Building that on the cheap would yield no result or inconclusive results.

I don't know if NDAs are the hurdle with poor publication. Could it be that all interested parties (theoreticians, experimenters, backers) are more interested in patents and commercialisation prospects than a Nobel ? Would they deliberately keep the things fuzzy as to keep their work under the radar of big labs, preserving the "fringe science factor" as a cover to further refine their design in secret ? Why publish anything at all then ? Just one single reproducible working device detailed design, even with lousy thrust/power ratio, would see millions if not billions $ rushing on such effect. Wonder how many labs quietly tried a shot "on the cheap" at that, saw nothing, kept silence on that null result and returned to their serious activities...

@John and those believing nothing conclusive can come out of the data because of its sketchy nature, I'm sure we all understand that it might very well be the case that indeed nothing conclusive can come at this stage with data acquired (and released) so far. But how we could know that for sure if not trying ? And even if nothing conclusive can be inferred, we can still further the subject about what is outright impossible and what is still on the table. Also surveys of many (ok, not that many in present situation) unreliable sources can turn up aspects unseen by each individual publication. This is not automatic, there is no assurance that all this time and energy won't be a waste, this is the rule of the game of being impatient (and I see lot of impatient people here) that is somehow also the rule that applies when undertaking anything at the edge and high risk/high payoff. Though in this case I wonder who would pay us... so we are only left with the high risk  :)

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