Author Topic: EM Drive Developments - related to space flight applications - Thread 8  (Read 1560576 times)

Offline MrFrankenverse

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Offline WarpTech

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To put it simply, physics as we know it requires a force to THROW THE BALL! If you're in a funnel shaped copper cavity headed towards the moon, and you throw a tennis ball towards the moon, you and your cavity are accelerated away from the moon due to the energy required to THROW THE BALL. The tennis ball can then hit a steel plate, a mattress, or glance off the walls. It doesn't matter. When all of the energy has dissipated and the ball has come to rest, the net result is zero gain in momentum. At the most basic level, this is the fundamental issue with the Emdrive, and the issue every one here is trying to explain.

EDIT: Of course, an Emdrive is constantly stuffing more and more tennis balls into your copper cavity, and insisting that you throw them in a collimated fashion so that as one tennis ball is leaving your hand, the last one you threw is just exactly bouncing off the wall of your choice (hence all of the discussion about modes and Q). The more tennis balls you can deal with, the greater the Q. The end result is the same. You're going nowhere at a great rate, surrounded by tennis balls. Unless, of course, current physics is incomplete. And I'm sure it is  ;)

This is only the issue if you think photons act like tennis balls and ignore the fact that copper can absorb EM waves as heat, based on the fact that it cannot absorb tennis balls.
« Last Edit: 11/23/2016 01:39 am by WarpTech »

Offline OnlyMe

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I wrote a popular article on the emerging EmDrive physical theory described in the EW paper. This is a short and hopefully readable outline of the developing theoretical model proposed by the NASA scientists. I think reversing the order of the considerations in the paper can make the outline easier to follow. Criticism welcome.

NASA Scientists Sketch Tentative Theory of EmDrive Propulsion
https://hacked.com/nasa-scientists-sketch-tentative-theory-emdrive-propulsion/

One issue is NASA measured static force generation big to small with a dielectric at the small end and small to big when the dielectric was not used.

Roger Shawyer, in 2002 and in 2006 also measured static force being generated in non dielectric frustums small to big as attached.

Would like to see any of these theories explain the small to big non dielectric static force generation that has been measured by NASA and Roger.

For sure, any theory needs to be able to explain ALL the measured data.

Or the systemic and/or experimental error that lead to the data in question....

I harp on this because even though you continue to point to Shawyer's past claimed results, there is very little in the way of published design detail of either the frustums or experimental equipment and environment, he used.

It makes the claims sound a great deal more like hearsay, than the result of real experimental data... And I am not saying that there was not data, just that it does not seem to be available for critical examination.

Have you read both of Roger's recently posted engineering test reports for the Experimental & Demonstrator EmDrives as attached?

As an engineer,  there are more than enough data to replicate both the EmDrives and the fairly simple static force measurement systems. Here Roger had an advantage over EW as the force was 100s of times greater than the 100uN EW had to deal with.

I see the 2 test reports as equivalent to the earlier EW in air test report.

Phil, maybe better to ask another engineer if those documents provide enough information to reproduce Shawyer's work on its own... Both the build itself and experimental controls.

I am not an engineer, and my only real personal interest has been theoretical physics. Still it seems to me that if you believe those documents or really any of those that predate them, provide sufficient information to actually recreate Shawyer's work, without a long period of trial and error of your own.., you have to be reading/working from some special knowledge base not included in the published work.

How many DIY experimenters and two or three institutional labs have been playing with this for the last few years, and how many of those have each tried their own interpretation of what should work, with varying degrees of success or failure. A fact that in itself demonstrates just how vague, much.., if not all of what Shawyer has shared publicly has been.


Offline M.LeBel

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EW is not alone in observing there is a time for the force to build up.

Roger also observed it with both the Experimental and Demonstrator EmDrives as attached.

I believe it has to do with the operational best point of the EmDrive being slightly off and the EmDrive pulling the natural resonant freq to be a better match to that of the applied Rf.......

  ...... So YES EmDrives can SOMETIME be slow to generate their force as evident by both EW's data and by Roger's data. Here again EW confirm what Roger measured way back in 2002 and 2006.

IMO, and as previously discussed, everything we have a grasp on is made of these quantum vacuum fluctuations (qvf); B field, E field, em waves, matter etc.  So, we are already playing a lot with these qvf but not in the best of ways. 

So, one possible explanation, to the slow build up of the force (above) may indicate/suggest a proper polarization or sorting build-up and accumulation of these qvf...  forming the required causal structure, i.e. a time rate differential across some portion of the test article..

Food  for thought ...

Here's a more practical idea. My theory says that the thrust is due to asymmetrical power dissipation (losses) and dispersion. Perhaps it takes a while for the metal to heat up. Resistance increases with temperature, creating higher losses and there may be a threshold where the asymmetry is finally enough to produce a measurable effect. I have not seen any results for a fully superconducting EmDrive.

From what I know about the QV, 99.999% of the energy is in the bandwidth STARTING at 10^22 Hz and going up from there. This is why I do not see MiHsC as a viable theory, nor do I see Dr. Whites QV model as a viable option. The modes that are not allowed in the frustum are "negligible" in comparison to the vacuum energy density starting at 10^22 Hz and up, where matter is transparent and the asymmetry results in Gravity. The EmDrive is operating 13 orders of magnitude lower frequency. So to me, the QV is out of the picture.

I like practical too .. Your power dissipation differential is like a rocket motor ... make sense.
But the underlying cause is still a time rate differential. As explained previously, matter exists more and falls spontaneously toward a slower rate of time, as in gravity. This is because slower time and longer seconds means/requires larger space to keep c ratio constant. Therefore, the object loses power as it falls into larger space, making this a typical entropic/spontaneous event.

First step is to create a time rate differential so that, second step, object falls spontaneously across the differential. We never act directly on objects. We exchange and transfer time frames (pilot waves) and change power.  A blue photon bouncing off (non-elastic collision) will lose power, since the same Planck content h is now packaged into the longer time period of a redder photon. The Planck h content is the same; only power has changed by virtue of a longer time package (period) or, equivalently, a longer wavelength (space). All that we put on paper is one order over integrated in time, which is why the rate of time is nowhere to be found. Energy or mass means nothing real unless we specify its space or time container, i.e. its power. GR spirit without the map.

New physics or new philosophy? or, just nothing new?

Offline TheTraveller

So, once again, you need a force locked loop, not a phase locked loop (and NOT the frequency locked loop you are currently chasing). The difference is a fairly trivial modification to the "magic happens inside" box you have shown ad nauseum in your "schematics".

EW in the 1st 2 papers used a phase locked loop via a 2nd sense antenna. I believe they took my advise and have developed a reflected power freq tracker that dithers the freq to find lowest reflected power.

I agree as my freq tracker is not a phase locked loop, but 1st you need to tune to lowest reflected power or you will never get to a Force locked loop.

For my rotary test rig, the freq tuner will work from.

1) lowest reflected power.

2) highest force for static testing

3) highest acceleration for dynamic testing.

Updated freq tracker overview attached.
It Is Time For The EmDrive To Come Out Of The Shadows

Offline TheTraveller

Phil, maybe better to ask another engineer if those documents provide enough information to reproduce Shawyer's work on its own... Both the build itself and experimental controls.

I am not an engineer, and my only real personal interest has been theoretical physics. Still it seems to me that if you believe those documents or really any of those that predate them, provide sufficient information to actually recreate Shawyer's work, without a long period of trial and error of your own.., you have to be reading/working from some special knowledge base not included in the published work.

How many DIY experimenters and two or three institutional labs have been playing with this for the last few years, and how many of those have each tried their own interpretation of what should work, with varying degrees of success or failure. A fact that in itself demonstrates just how vague, much.., if not all of what Shawyer has shared publicly has been.

I have no special information. What I know from Roger's bread crumbs to me has been shared here. Put those breadcrumbs together with his latest 2 reports and building an EmDrive is not hard.

I do know that when Dave followed Roger's build process and moved from a copper mesh frustum with almost no force generation to a solid copper frustum that was highly polished, he measured 18.4mN of force generation.

What I do know, from what I have read, is almost no EmDrive builder follows Roger's lead, well at 1st. Then with experience as their guide, they build following Roger's lead.

Paul has shared he is building a non dielectric, spherical end plate frustum. Which is what Roger has advised he did with the Demonstrator and Flight Thruster builds and what I have done. For my build Roger has predicted, if I do the build to a very high quality, as I have done by using an external fabricator, that my Qu should be around 88k and my specific force around 500mN/kW. Late 1st qtr 2017, I will know if that is the result.

So it seems there is a build process to go through, that has so far, as far as I have seen, resulted in those builds that follow Roger's build guidelines generating force and those that do not, do not generate force.

You see I'm not a big fan of reinventing the wheel because it can be reinvented. Others opinion on that may vary.
« Last Edit: 11/23/2016 03:56 am by TheTraveller »
It Is Time For The EmDrive To Come Out Of The Shadows

Offline WarpTech

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Here's a more practical idea. My theory says that the thrust is due to asymmetrical power dissipation (losses) and dispersion. Perhaps it takes a while for the metal to heat up. Resistance increases with temperature, creating higher losses and there may be a threshold where the asymmetry is finally enough to produce a measurable effect. I have not seen any results for a fully superconducting EmDrive.

From what I know about the QV, 99.999% of the energy is in the bandwidth STARTING at 10^22 Hz and going up from there. This is why I do not see MiHsC as a viable theory, nor do I see Dr. Whites QV model as a viable option. The modes that are not allowed in the frustum are "negligible" in comparison to the vacuum energy density starting at 10^22 Hz and up, where matter is transparent and the asymmetry results in Gravity. The EmDrive is operating 13 orders of magnitude lower frequency. So to me, the QV is out of the picture.

I like practical too .. Your power dissipation differential is like a rocket motor ... make sense.
But the underlying cause is still a time rate differential. As explained previously, matter exists more and falls spontaneously toward a slower rate of time, as in gravity. This is because slower time and longer seconds means/requires larger space to keep c ratio constant. Therefore, the object loses power as it falls into larger space, making this a typical entropic/spontaneous event.

First step is to create a time rate differential so that, second step, object falls spontaneously across the differential. We never act directly on objects. We exchange and transfer time frames (pilot waves) and change power.  A blue photon bouncing off (non-elastic collision) will lose power, since the same Planck content h is now packaged into the longer time period of a redder photon. The Planck h content is the same; only power has changed by virtue of a longer time package (period) or, equivalently, a longer wavelength (space). All that we put on paper is one order over integrated in time, which is why the rate of time is nowhere to be found. Energy or mass means nothing real unless we specify its space or time container, i.e. its power. GR spirit without the map.

New physics or new philosophy? or, just nothing new?

I use the decay time as the reference, not the clock time, but yes that is the correct physics. The problem with the red shift/blue shift of photons is that; in order for the resonant frequency to remain constant, the orthogonal components of that frequency or wavelength must vary with the geometry of the frustum.

For a TE012 or 013 mode...
1. The radial wavelength is longer toward the small end and shorter toward the big end.
2. The zenith wavelength is longer toward the big end and shorter toward the small end.
3. The sum of the squares of the two frequencies at each end is the square of the resonant frequency, and supposedly constant.

So while one wave is red shifting, the other wave is blue shifting, in the same direction! It is only when I add asymmetrical power dissipation to the equation, that this symmetry is broken and there are losses that "do work" on the frustum. Dispersion with a constant resonant mode alone will not do it since there is no "work" being done on the copper. Energy must be dissipated to get out of the cavity. As long as the energy persists in the cavity, there can't be any thrust. By "out of the cavity" I mean "into the copper", and then isotropically radiated as heat.

I think the conservation of energy issue will be resolved because the metal gains heat and entropy increases. It will take more energy to push a hot frustum than a cold one.

Offline OnlyMe

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Simple feedback or energy dissipation, by themselves, do not make a copper cavity a complex system...

For me, as an engineer that builds EmDrives by applying Roger's theory equations, it is not complex at all. I understand the physics, as explained by Roger, and when applied to the real world, see it generate the predicted results.

As for Q * power scaling linear with force generation, that is just accelerator physics as is the relationship between Q and Rs and temp and freq. Of course in the real world not everything scales linear but as I see it, the vast majority of the effects do scale linear because if not there would not be accelerator cavities with Q 5x10^11.

So for sure it will not be a simple build to get a high performance room temp cavity to work well when immersed in LN2, but doing so it not something that has never been done before and thankfully Google is really good at digging out build data.

With a Cu 300K (room temp) Rs of around 8,000uOhm and a 77K Rs of around 15uOhm, there is more than ample margin to experimentally measure both the resultant Qu from doing forward power 1x Tc rise time calcs and doing force generation.

It then gets very exciting and interesting to do real time Q measurements with a non accelerating and accelerating thruster to see if the Q drops during acceleration and then to measure the energy representative of the Q drop which has exited the cavity and is doing work to accelerate the EmDrive.

That should be VERY interesting data as only a small increase in angular velocity on a rotary test rig should be sufficient to measure gained KE vs cavity energy drop from dropped Q.

More data will be added by reducing Rf amp power to become low enough to maintain constant velocity as against rotary test rig static and dynamic air resistance load and again record what happens to cavity Q as power is varied up and down around that constant velocity point.

Interesting times ahead.

And then again...,

There is a difference between Shawyer's theory and the formulas he and it seems you use to describe and predict, the design and performance of an EmDrive. It has always seemed to me that Shawyer's evolution of the EmDrive has been based on an engineering based trial and error. Thus his math based formulas also seem closer to having been derived from the engineering experience.., trial and error...

Beyond that I remind you again that any attempt to use how the efficiency of particle accelerators scales is fatally flawed in that the EmDrives being publicly discussed operate at very different frequencies and incorporate very different technologies. That being the case a there is a far greater burden on you to explain just why what is seen in the case of an accelerator, might apply in the case of a copper box filled with microwaves....

Roger's EmDrive theory was developed by a group of UK academics and aerospace experts, funded by some of the money provided by the UK gov. The whole program,  theory development, creation of the EmDrives, test rigs and review of the test data was handled by a UK MOD select panel of experts.

BTW non SC accelerator cavities are copper boxes filled with microwaves. If you think accelerator cavity theory doesn't apply to EmDrive cavities, please review this data and point out what does not apply:

https://en.m.wikipedia.org/wiki/Superconducting_radio_frequency#Physics_of_SRF_cavities

The claim that, Roger's EmDrive theory was developed by a group of UK academics and aerospace experts,..., seems hollow when the details of development remain hidden, to the extent that very knowledgeable persons with applicable backgrounds, don't see what you have come to believe is obvious. Point to a comprehensive peer reviewed theory paper, that can be reviewed and confirmed or critiqued.

On the dissimilarity between an EmDrive and particle accelerators, the only particles anyone has suggested an EmDrive accelerates are virtual... And particle accelerators are not boxes in the same sense that an EmDrive is. Most of your wiki reference was focused on super conducting particle accelerators, not the simple copper versions.... At least as public information superconductor EmDrives are yet to be a functional reality.

My criticism of your using superconducting accelerators as a proof of how the thrust of a superconducting EmDrive scales, has been that it is an assumption, that you present as a priori. The similarities may be used as a guide but not as a matter of fact, until it has been tested and proven. They are not identical systems and there are significant disimilarities.

Phil, before we get anywhere near that point, the point where we can talk about how thrust scales with design or RF power, someone needs to do what EW did when they demonstrated reproducible thrust over a series of tests. We just need that reproducible thrust to be a bit more significant, so it cannot be confused with systemic and/or measurement error.

It appears that some consensus is developing, among the main players, builders and those providing design support, that is beginning to drive design in a relatively common direction. A direction where higher thrusts seem promising. But we are not there yet, at least not in publicly documented design detail and experimental data.

One more thing... If you say something often enough or even tell yourself something long enough, it begins to take on a life of its own, independent of whether it has been proven. For science to progress and evolve, it is important to understand the line that separates what is known, as in has been proven, and what we believe...

The engineers I think have an advantage there, so long as they don't become caught up in theory, and forget they are engineers. I believe the engineers in us adapt better. What we know to be true, evolves far more easily than what we believe ....

I do tend to rant and run on....

Keep in mind I am a believer or more accurately have become a believer, but I also have a interest in maintaining a clear distinction between what is known and what remains theory or even a reasoned and logical projection.., of what we believe.

Offline TheTraveller

The claim that, Roger's EmDrive theory was developed by a group of UK academics and aerospace experts,..., seems hollow when the details of development remain hidden, to the extent that very knowledgeable persons with applicable backgrounds, don't see what you have come to believe is obvious. Point to a comprehensive peer reviewed theory paper, that can be reviewed and confirmed or critiqued.

If you read the documents and statements made by Roger, it is very clear how the theory development happened. As part of the requirements of the 1st round of funding, both experimental results and theory had to be developed and approved by the UK MOD select panel.

Please also consider, the theory development group had a working EmDrive to study, poke and prod. Maybe ask yourself what would be the theory development process if you and others, in a gov funded theory development group, had a working EmDrive to base your theory development on?

I do realise that I'm probably the only one who understand and accepts Roger's theory. I have no issue with that as I know that given time, the other theories will fall by the way side as they fail to explain and describe ALL the experimental data, such as

1) Static force being measured small to big and Dynamic force being measured big to small.

2) Static force reversal when there is or not a dielectric at the small end.

This data is real and has been measured by Roger and confirmed by EW. Well EW confirmed the non dielectric static force direction small to big on 2 frustums and on 2 very different test rigs.

So the data mounts, the hill that other theories needs to climb gets steeper and life get interesting.
« Last Edit: 11/23/2016 04:49 am by TheTraveller »
It Is Time For The EmDrive To Come Out Of The Shadows

I wrote a popular article on the emerging EmDrive physical theory described in the EW paper. This is a short and hopefully readable outline of the developing theoretical model proposed by the NASA scientists. I think reversing the order of the considerations in the paper can make the outline easier to follow. Criticism welcome.

NASA Scientists Sketch Tentative Theory of EmDrive Propulsion
https://hacked.com/nasa-scientists-sketch-tentative-theory-emdrive-propulsion/

Nice job, but Prof's Woodward and Fern just published an article in JBIS that refutes NASA's Quantum Vacuum conjecture. I would be interested in seeing Dr. White's rebuttal of that article. In the way the model is presented, I think Woodward and Fern are correct. However, there are other ways to use the QV to accomplish this that they do not mention, and that differs from Dr. White's approach. (AKA my approach to QG.)

Thanks. I am unable to find recent JBIS articles by Woodward and Fern. Can someone post a link, or just the title?

Offline TheTraveller

I think the conservation of energy issue will be resolved because the metal gains heat and entropy increases. It will take more energy to push a hot frustum than a cold one.

Roger has told me he has data supporting the cavity Q drops during acceleration and that the cavity momentum drop represents the accelerating frustum's gained momentum. Have asked him to released the data, that is if it is outside any NDA restrictions. He said he will see it that is possible.
« Last Edit: 11/23/2016 04:44 am by TheTraveller »
It Is Time For The EmDrive To Come Out Of The Shadows

Offline TheTraveller

Simple question to the Forum

If you theory guys had a working EmDrive, on a rotary test rig, at your disposal, what would be the process to develop an acceptable theory to explain what you are observing?

What data would you need from the test rig?

Please try to be specific so I can ensure that data is available.
« Last Edit: 11/23/2016 04:53 am by TheTraveller »
It Is Time For The EmDrive To Come Out Of The Shadows

Offline TomH

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Offline high road

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So, when the cubesat EM-drive is launched, can I assume it will get its own thread somewhere other than the new physics section? Or at least a link from the live event section or space science section? Because in the new physics section, there's a lot of endless debate to trudge through to find the grains of information. It would be nice to separate the discussions from updates. And naturally, there's no reason to wait for the launch to do this.

Offline flux_capacitor

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I wrote a popular article on the emerging EmDrive physical theory described in the EW paper. This is a short and hopefully readable outline of the developing theoretical model proposed by the NASA scientists. I think reversing the order of the considerations in the paper can make the outline easier to follow. Criticism welcome.

NASA Scientists Sketch Tentative Theory of EmDrive Propulsion
https://hacked.com/nasa-scientists-sketch-tentative-theory-emdrive-propulsion/

Nice job, but Prof's Woodward and Fern just published an article in JBIS that refutes NASA's Quantum Vacuum conjecture. I would be interested in seeing Dr. White's rebuttal of that article. In the way the model is presented, I think Woodward and Fern are correct. However, there are other ways to use the QV to accomplish this that they do not mention, and that differs from Dr. White's approach. (AKA my approach to QG.)

Thanks. I am unable to find recent JBIS articles by Woodward and Fern. Can someone post a link, or just the title?

I already referenced it to you in a post regarding your new article. Here it is again:

Fearn, H.; Woodward, J. F. (May 2016) "Breakthrough Propulsion I: The Quantum Vacuum", JBIS Vol. 59, N° 5.

It would be a good thing we discuss the content of this paper here :)

Offline Flyby

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......
I'm asking for more insight on the relation between momentum and reflectance, because it would have profound implications :

If i may simplify the situation a bit to explain what was perhaps a bit too poorly elaborated :

I recall the discussions about the tennis balls bouncing back and forth in a huge frustum space station.

As long you consider the reflectance of the walls to be uniform in every direction, it is only the angle of incidence that will determine the size of the momentum. And in the end, when you add up all bounces, the final sum of all forces will be zero. That much I understood...

But I see a problem if the reflectance of the walls would vary according the direction you throw the balls. It would mean that for the direction (small end > big end) the transfer of momentum/force would be smaller then what the angle of incidence would predict.

So, it puzzles me on how the relation is then, between the reflectance and the momentum transfer ?

To put it simply, physics as we know it requires a force to THROW THE BALL! If you're in a funnel shaped copper cavity headed towards the moon, and you throw a tennis ball towards the moon, you and your cavity are accelerated away from the moon due to the energy required to THROW THE BALL. The tennis ball can then hit a steel plate, a mattress, or glance off the walls. It doesn't matter. When all of the energy has dissipated and the ball has come to rest, the net result is zero gain in momentum. At the most basic level, this is the fundamental issue with the Emdrive, and the issue every one here is trying to explain.

EDIT: Of course, an Emdrive is constantly stuffing more and more tennis balls into your copper cavity, and insisting that you throw them in a collimated fashion so that as one tennis ball is leaving your hand, the last one you threw is just exactly bouncing off the wall of your choice (hence all of the discussion about modes and Q). The more tennis balls you can deal with, the greater the Q. The end result is the same. You're going nowhere at a great rate, surrounded by tennis balls. Unless, of course, current physics is incomplete. And I'm sure it is  ;)
Sigh.. I knew this would happen the moment I started writing about tennis balls...
I thought it would be more clear the tennis ball analogy is rather flawed, but apparently, it isn't... :-[

It is not about the total sum of all the action/reactions I'm writing about, but I'm trying to get the understanding about reflection right.
Reflection is the most essential feature/process of what happens inside an EMdrive.
If you take 1 complete cycle, going from big end to small en and back, the total sum of the reflectance from small to big end is < then the total sum, especially when you consider it to be a wave, instead of a particle.
The problem with particles is that we associate the too much with real life observations where hard kinetic impacts have an apparent linear relation with the angle of incidence.

I'm not trying to explain the EMdrive with this, I don't have a comprehensive theory. I only have questions.
In this case about reflection and its relation with force/momentum transfer, because it is the most essential part of what happens inside an EMdrive.
The non linearity of reflection is really counter-intuitive and understanding it "might" give a clue to why an EMdrive functions. (IF it really functions).

My idea is that - IF the EMdrive does indeed work - we need to see and rethink what misconceptions we have, because maybe we then can find clues that help solve these apparent conflicts.

The EMdrive (probably) does not violate CoM. The press likes sensation but totally reverses the logic...
 
The question should be : what did we miss in our understanding of CoM, that doesn't need "new physics", but only a more accurate understanding of what's happening...
This means retracing, step by step, what we know and investigating any of the shortcuts we took for granted for so long...

Because it is a resonance cavity, any minuscule variation can get potentially amplified (Q 100k ? or more) to a point it becomes no longer negligible...

So questions like : what brings us the non-linearity of reflection, or the extraordinary momentum/spin in evanescent waves, become important because they're not really considered in our daily understanding of the world around us.

As far as comprehensive theories goes, I do have a preference for Todd's asymmetric dissipation/attenuation based upon the wave properties of RF waves...It's way above my head how he does it, but it looks like a logical and elegant solution to the apparent CoM/CoE conflict...
« Last Edit: 11/23/2016 09:39 am by Flyby »

Offline Flyby

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"frontpage" on National Geographic :

http://news.nationalgeographic.com/2016/11/nasa-impossible-emdrive-physics-peer-review-space-science/

 8)

another great article :
http://arstechnica.com/science/2016/11/nasas-em-drive-still-a-wtf-thruster/

skeptical but with a sense of humor. Does make a few good points, though.
 f.e. about the relative low sampling rate of the EW results...
It is a something that crossed my mind too.
« Last Edit: 11/23/2016 09:25 am by Flyby »

Offline mwvp

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...
An empty closed copper cavity in the shape of a truncated cone and electromagnetically excited at a microwave frequency at kW or less power is now deemed to be a complex system?  :o
...
Simple feedback or energy dissipation, by themselves, do not make a copper cavity a complex system...

While true, when you consider the total system - the PLL with its mixer and filter; the thermal TC of the frustrum, the potential for acoustic vibration resulting from radiation pressure causing frequency spread; in Shawyer's setup, piezoelectric tuning with its feedback filter and the spring system his whole frustrum is mounted on, and the acceleration of all the above, the total system can have lots of poles & zeroes of the transfer function and all those sources of mixing. It could get ugly, even chaotic, but it doesn't have to if constructed and feedback loops filtered accordingly.

It would have been nice if EW had included a graph of frequency, or the VCO control voltage on those thrust plots.

Offline mwvp

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Simple question to the Forum

If you theory guys had a working EmDrive, on a rotary test rig, at your disposal, what would be the process to develop an acceptable theory to explain what you are observing?

What data would you need from the test rig?

Please try to be specific so I can ensure that data is available.

Not even measuring thrust, I would like to see multiple taps, say 6 taps in a 3 mode frustrum at 90 degree (quadrature) separation to measure amplitude and phase as the frustrum accelerates and decelerates to validate motor and generator modes. The amplitude of a slow-traveling standing wave in static, and accelerating conditions.

This would be relatively cheap and simple, and from it thrust (as miniscule as may be from a 10mW signal generator) could be calculated. That part of Shawyer's theory would be validated. I've thought about bouncing a can on a slinky. But why bother. It would just confirm what we know, others would discount it.

But it would be useful, in that it would validate simulations, especially the reduction of an intractable three dimensional accelerating frustrum to a single dimensional model.

Offline flux_capacitor

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Simple question to the Forum

If you theory guys had a working EmDrive, on a rotary test rig, at your disposal, what would be the process to develop an acceptable theory to explain what you are observing?

What data would you need from the test rig?

Please try to be specific so I can ensure that data is available.

You already know the critical parameters. I hope others will jump in the suggestion bandwagon. Here is mine:
I know there will be a ton of sensors. But besides those, please record a long sequence-shot video (no cut, with ambient sound) of your complete rotary experiment from above, the camera lens pointing downwards along the Z-axis of the rotary test rig, so anyone can later easily plot angular displacement and acceleration solely on the basis of the video. Better, record multiple flux at once, one video from the top and another video with a second camera on a tripod somewhere on the side of the room. Make sure overall lighting is high but without any reflection in camera lenses (digital cameras produce horrible noise under low light conditions).
« Last Edit: 11/23/2016 09:54 am by flux_capacitor »

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