Author Topic: EM Drive Developments Thread 1  (Read 764861 times)

Online aceshigh

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Re: EM Drive Developments
« Reply #720 on: 09/17/2014 10:57 PM »
The only explanation I demand at this time is, "Eppur si muove".  Everything after that will just be detail. I just need to see it move a bit more clearly.

Once an unambiguous thrust signal is available, we can test it pointing in all directions, including up and down, at all times of day, at different altitudes, stationary and accelerating, on the ground and in orbit... We'll learn if it can be used as an over unity device or not, whether it's effected by the proximity of other masses, a lot of things.

Observational data is everything. Theory follows that. That's my view.

the problem I guess is that obviously, it's somewhat of a catch 21 isn´t it? Nobody will deposit the amount of funds needed to develop in a short amount of time the test devices, IF the theory is controversial and the thrust too small and doubted as noise signal.

and the theory (or theories) will not cease to be controversial while the thrust is too small to be perfectly detectable to the point of easily excluding any other source (when it's easily detectable at plain sight, it will be a question of finding an explanation to it, just as we know 90% of the mass of the universe is lacking, but can´t really explain it)

so, the only way to do it is to progress very slowly, with little funds available.


Offline Rodal

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Re: EM Drive Developments
« Reply #721 on: 09/17/2014 11:03 PM »
I took dimensions of the Tapered (Frustum) Cavity thruster off the photo as suggested, using the 1.5 inch square beam end as reference. I got this in inches:
9.9 Major diameter, 6.6 Minor diameter, 9 Length.
It's probably a little bigger than that. I don't know how to deal with parallax.

Thank you, aero.  That's also helpful to me for my guesstimation purposes trying to figure out what effect is being measured. 

Offline John-H

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Re: EM Drive Developments
« Reply #722 on: 09/17/2014 11:12 PM »
Well, it seems that IF we get the same thrust with the same energy input at some high velocity, then conservation of energy will be  violated. However, all we have seen so far is that we get thrust when the apparatus is at rest, and since there are very few observations, and no agreement on the theory, the thrust and power could easily vary in a way that satisfies established physics. There could be a new and useful effect there that doesn't break the laws of nature.

Or there could  be errors in the experiment.

Offline raketa

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Re: EM Drive Developments
« Reply #723 on: 09/17/2014 11:50 PM »
I am electrical engineer and I understand how electric engine works. But if I start to think how in the reality these magnetic field interact and what make engine spin, I have admit I couldn't give you exact explanation. If we accept investigate just obvious facts, we will never build this type civilization. Your comment is similar to opposite comment just accepted that is working. We will see when follow experiment will be finish.

Quote
From my perspective I feel these types of comments keep getting raised because the authors want something to force the collective community to either take notice or prove them right. Shouldn't the onus now be on the critics. Shouldn't the critics be required to attempt a reproduction and publish their results, even if it is in Conference Proceedings.

Maybe in a perfect world, but not this one. See GoatGuy's proofs that it cannot work. That's a proof easy to do, all you need do is ignore one source of energy while claiming that your argument is complete. It doesn't help that there is no agreement on what that ignored energy source is and only those who have positive experimental results "know" that it does exist.

Offline cuddihy

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Re: EM Drive Developments
« Reply #724 on: 09/18/2014 02:28 AM »
The only explanation I demand at this time is, "Eppur si muove".  Everything after that will just be detail. I just need to see it move a bit more clearly.

Once an unambiguous thrust signal is available, we can test it pointing in all directions, including up and down, at all times of day, at different altitudes, stationary and accelerating, on the ground and in orbit... We'll learn if it can be used as an over unity device or not, whether it's effected by the proximity of other masses, a lot of things.

Observational data is everything. Theory follows that. That's my view.

Yes, ultimately. But in the meantime, it's important to deal with a theory of how it works to properly understand what a valid result is.

For instance, the first rigorous Woodward/ Mahood tests got thrust results -- but that did not scale as the "naive" theory said they should. Disproving Woodward's original hypothesis about the easiest way you could see a transisent mass fluctuation. (An assumption that micro-acceleration of atoms within a dieletric would be sufficient to cause a mass fluctuation--current theory says bulk acceleration of a substantial mass is required.)

Without the theory, Eppur si muove.

This initial failure has also raised the bar for Woodward in many sceptics' minds.

Offline aero

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Re: EM Drive Developments
« Reply #725 on: 09/18/2014 04:06 AM »
I took dimensions of the Tapered (Frustum) Cavity thruster off the photo as suggested, using the 1.5 inch square beam end as reference. I got this in inches:
9.9 Major diameter, 6.6 Minor diameter, 9 Length.
It's probably a little bigger than that. I don't know how to deal with parallax.

Shouldn't the cavity be the same diameter as the wave length of the resonate cavity? In any case, I calculate the wave lengths of the 3 frequencies used as
0.155123905 m = 6.107240338 inch
0.154795507 m = 6.094311291 inch
0.159430152 m = 6.276777642 inch

I guess I don't quite understand resonance.




Retired, working interesting problems

Offline raketa

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Re: EM Drive Developments
« Reply #726 on: 09/18/2014 04:22 AM »
Device does not look too complicated, modify microwave. Most of the hassle is with creating environment that will not effect measured thrust.
I understand issue to bring it on the board of ISS, what about build simple version and place it in trunk of Dragon and tested after departure from ISS, keep Dragon for couple days on the orbit.
I think it could be achieve in year and we will have answer without doubt.

Online ThinkerX

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Re: EM Drive Developments
« Reply #727 on: 09/18/2014 05:31 AM »
At this point, I'm starting to wonder if some of the more hands-on inclined people here won't start building their own versions of these things in their garages.  From the photo's, the mechanisms themselves appear fairly simple, something a competent machinist could craft over a couple weekends. 

Offline raketa

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Re: EM Drive Developments
« Reply #728 on: 09/18/2014 08:31 AM »
I am just worry there is some know-how that is not publish about this device. And then you have hurdle to bring it to orbit. Maybe crowd funding could help build and launch it as cubesat. I will definitely help finance, to give chance dream to become solar system civilization.
At this point, I'm starting to wonder if some of the more hands-on inclined people here won't start building their own versions of these things in their garages.  From the photo's, the mechanisms themselves appear fairly simple, something a competent machinist could craft over a couple weekends.

Offline cuddihy

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Re: EM Drive Developments
« Reply #729 on: 09/18/2014 10:29 AM »
Again, the forces current devices exhibit is far less than small satellites see from solar pressure, drag, etc. So any effect would be hard to pull out, especially when you factor in the mass required to power it. Add in the complication that those forces are constant and these devices have only been tested for seconds at a time, it's a recipe for wasted money.

Offline Rodal

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Re: EM Drive Developments
« Reply #730 on: 09/18/2014 11:45 AM »
I took dimensions of the Tapered (Frustum) Cavity thruster off the photo as suggested, using the 1.5 inch square beam end as reference. I got this in inches:
9.9 Major diameter, 6.6 Minor diameter, 9 Length.
It's probably a little bigger than that. I don't know how to deal with parallax.

Shouldn't the cavity be the same diameter as the wave length of the resonate cavity? In any case, I calculate the wave lengths of the 3 frequencies used as
0.155123905 m = 6.107240338 inch
0.154795507 m = 6.094311291 inch
0.159430152 m = 6.276777642 inch

I guess I don't quite understand resonance.

Given the fact that you had to guesstimate the device's dimensions, the comparison between the wavelengths they used and the guesstimated diameters is not bad.  For the minor diameter: 

(6.6" Minor diameter)/(6.277 inch wavelength) = 1.051 ---> only 5% difference.

What do you think of the dielectric resonator influence ?

<<Tapered Cavity RF Evaluation, General.......The COMSOL analysis iteration process was used prior to assembly to determine the optimal thickness and diameter of the dielectric RF resonator disc located at the small end of the thruster. The geometry of the RF resonator disc is a function of the resonator material’s relative permittivity, dissipation factor, and target resonance mode.>> p.12

<<F. Tapered Cavity RF Evaluation, General Findings and Lessons Learned
Overall, the biggest lesson learned was that RF tuning and optimization constraints are very challenging. We discovered early in the COMSOL® analysis process that just because you can achieve a great RF solution does not mean that it will be an ideal Q-thruster implementation.
There appears to be a clear dependency between thrust magnitude and the presence of some sort of dielectric RF resonator in the thrust chamber. The geometry, location, and material properties of this resonator must be evaluated using numerous COMSOL® iterations to arrive at a viable thruster solution. We performed some very early evaluations without the dielectric resonator (TE012 mode at 2168 MHz, with power levels up to ~30 watts) and measured no significant net thrust.>> p.18
« Last Edit: 09/18/2014 12:31 PM by Rodal »

Offline Rodal

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Re: EM Drive Developments
« Reply #731 on: 09/18/2014 12:51 PM »
I have seen people in blogs (not in this thread) bringing up the dynamic Casimir effect as perhaps being responsible for the EM drive thrust.  One problem with the dynamic Casimir effect is that the moving mirrors responsible for the effect need to move at relativistic speeds.   If the moving mirrors move at a speed that doesn't approach the speed of light, the virtual particle pairs will easily adapt to the mirror’s movement and continue to come in and out of existence without any dynamic Casimir effectThe speed of the mirror needs to match the speed of the photons to experience the dynamic Casimir effect, and since the photons move at relativistic speeds, this means that the mirror needs to move at relativistic speeds.  If the mirrors move at speeds approaching the speed of light, then yes, the virtual photons then become "real" (in the sense that they will interact with the mirrors) and the mirror begins to produce light.  The problem is that it’s impossible to get an ordinary mirror made of solid matter moving at anything approaching relativistic speeds.  The walls of the Shawyer, Cannae and Dr. White Frustum microwave devices are certainly not moving at relativistic speeds.

Wilson et. al.  (arxiv.org/abs/1105.4714) used, instead of a conventional mirror made of solid matter, a transmission line connected to a superconducting quantum interference device (SQUID). The SQUID changes the effective electrical length of the line and this is equivalent to the movement of an electromagnetic mirror.  When modulating the SQUID at GHz rates, the "mirror" moves back and forth. The transmission line is only 100 micrometres long and the mirror moves over a distance of about a nanometre. It achieves speeds approaching 5 per cent of light speed. Then Wilson cooled the medium (to 50mK), so that the photons would travel slower and match the "mirror" speed.  This worked: it was the first experimental confirmation of the dynamic Casimir effect, they spotted microwave photons emerging from the moving mirror, as predicted some time ago to occur.

But I don't see how this can relate to what Shawyer, Cannae and Dr. White did with the Frustum device:  Wilson had to use a superconducting quantum interference device (which Shawyer, Cannae and Dr.White did not), modulated at GHz rates, and the transmission line was only 100 micrometres long, and everything had to be cooled down.   The walls of the EM drives are not moving at relativistic speeds, and they are several inches apart instead of a nanometer apart.  There are no "mirrors" moving at relativistic speeds,  about a nanometre apart.  And the EM drives experiments are not conducted in a medium at very low temperatures (50mK) to slow down the photons to match the "mirror's" speed.
« Last Edit: 09/18/2014 01:38 PM by Rodal »

Offline JohnFornaro

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Re: EM Drive Developments
« Reply #732 on: 09/18/2014 01:39 PM »
...
6) Fantastic theories contrary to experience are suggested.

 "Conventional experience" has not  shown  A) translational momentum transfer imparted from .. virtual particles from the quantum vacuum, B) transient changes in mass resulting from EM, [M-E, Mach Effect, I think, is what you meant] and C) translational momentum imparted from EM explained in terms of .. Minkowski 3D+time stress tensor

Not sure if this particular check, so to speak, is a valid one. Given the breadth of human experience I would be willing to wager that if one was to limit research to only things humanity has experienced then it would not be practical for humanity to colonize the galaxy much less the entire universe. If memory serves there is nothing in the breadth of human experience up to the discovery of superconductivity that would have suggested that it was possible.

We should have a sidebar discussion about the transient changes in mass suggested by Mr. Woodward's interpretation of Mach and Sciama's theories.  Maybe in it's own thread, IDK.

Anyhow, I think Birchoff's error is merely a grammatical one. Langmuir's item #6 regards more the insistence of proposing that a "fantastic theory" is true, and does not suggest, as you did, to "limit" human research.  Propose all the goofy theories you want, but do not insist that they are true on the basis of verbal assertion alone.

Bit of a quibble in that the "breadth of human experience" is pretty darn broad, beginning, I think, with the invention of the wheel.  Here, the innovation was the mental picture of harnessing a naturally observed rolling action to do "unnatural" things, such as rolling a load of manure from point A to point B.  Maybe, even this wasn't an innovation, since the dung beetle had been doing this for years before humans appeared on the scene.  By "unnatural things", I mean to suggest that the Ares I rocket is/was an "unnatural thing", because it was a construct of human imagination in its original conception.

In the case of M-E, either the phenomenon exists, or it does not.  It is unlikely that the phenomenon did not exist in the distant past, and was recently called into existance by the interpretation of Mach and Sciama's literature.  Point being, if humanity should use M-E for the "unnatural thing" of going to Luna, (fer cryin' out loud, quit all this stargate talk) it would "just" be an addition to the human experience.

I think you have to take all of Langmuir's items into consideration, and that you shouldn't separate one of them out.  YMMV, natch.
« Last Edit: 09/18/2014 01:42 PM by JohnFornaro »
Sometimes I just flat out don't get it.

Offline JohnFornaro

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Re: EM Drive Developments
« Reply #733 on: 09/18/2014 01:39 PM »
All we have is a small set of thought to be positive results.

Fixed that for ya, and it doesn't detract from your argument in the least.
Sometimes I just flat out don't get it.

Offline JohnFornaro

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Re: EM Drive Developments
« Reply #734 on: 09/18/2014 01:40 PM »
In the current context, Rodal and others are saying effectively, “there is a distant moving mass, that of the Universe, expanding in all directions (isotropically?); insofar as retaining the Holy Grail of Physics is concerned (either conservation of momentum, or conservation of energy, take your pick), Mach's Principle and Woodward's derivations postulate that the Universe's expanding mass is creating an Inertial Field, which is also in continuous expansion, and if this is true, then perhaps the impulse-energy and Q-thruster devices are conserving energy if the inertial field and Universe mass is brought into play”

If the universe is expanding, then its mass must be increasing, and its energy must also be increasing.  If that is true, and a way can be figured out how to tap this increasing energy, then the effect would be to slow down the expansion of the universe.  But if there is an "inertial wind", then lo!  I am right in believing in the ether.

For example, I just got out of my chair and jumped up and down several times on the local planetary body, changing the universe ever so slightly, but changing it nevertheless.

Spare me the lesson about barycenters.  What I did is send out a rhythm of gravity waves which changes the inertial field of the same universe.

Point being, if this energy source could be tapped, it wouldn't change the universe all that much, at least at first.

Question being, can this be explained to a reasonably intelligent person?  Who might be an investor?  Right now, all of the explanations sound like those reporters who pestered Barry Goldwater.

« Last Edit: 09/18/2014 01:43 PM by JohnFornaro »
Sometimes I just flat out don't get it.

Offline JohnFornaro

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Re: EM Drive Developments
« Reply #735 on: 09/18/2014 01:40 PM »
Are you serious? R U Sirius?

Fixed that for ya.
Sometimes I just flat out don't get it.

Offline JohnFornaro

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Re: EM Drive Developments
« Reply #736 on: 09/18/2014 01:40 PM »
..."Eppur si muove".  ...

Observational data is everything. Theory follows that. That's my view.

Hey!  One post.  One like!  Keep that rate up and you gonna be president!


Il problema č: nessuno pensa si muove.

Sometimes I just flat out don't get it.

Offline JohnFornaro

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Re: EM Drive Developments
« Reply #737 on: 09/18/2014 01:41 PM »
it's somewhat of a catch 21

22.  My work here is never done.
Sometimes I just flat out don't get it.

Offline Rodal

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Re: EM Drive Developments
« Reply #738 on: 09/18/2014 01:55 PM »
...
6) Fantastic theories contrary to experience are suggested.

 "Conventional experience" has not  shown  A) translational momentum transfer imparted from .. virtual particles from the quantum vacuum, B) transient changes in mass resulting from EM, [M-E, Mach Effect, I think, is what you meant]

Well, I meant that conventional experience has not shown that ElectroMagnetic (EM) fields produce transient changes in mass (as posited by Woodward's interpretation of the Mach Effect), but however we word this you fully understood what I meant, and I agree with what you state in your latest post.  Woodward could answer that his effects are not meant to be conventionally experienced, but that's precisely what Langmuir was pointing out as one of the characteristics with which Langmuir identifies what he defines as Pathologic Science. So, if Woodward would answer that  his effects were never meant to be conventionally experienced, it would still meet that particular Langmuir characteristic with a "Yes".  By the way, Langmuir did not mean that something that meets his definitions of Pathological Science is necessarily bunk, or wrong, Langmuir just says "watch out," that if one is interested in the phenomena, further, more precise experiments need to be conducted by independent peers, before accepting the results.

« Last Edit: 09/18/2014 02:02 PM by Rodal »

Offline GoatGuy

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Re: EM Drive Developments
« Reply #739 on: 09/18/2014 01:59 PM »
In the current context, Rodal and others are saying effectively, “there is a distant moving mass, that of the Universe, expanding in all directions (isotropically?); insofar as retaining the Holy Grail of Physics is concerned (either conservation of momentum, or conservation of energy, take your pick), Mach's Principle and Woodward's derivations postulate that the Universe's expanding mass is creating an Inertial Field, which is also in continuous expansion, and if this is true, then perhaps the impulse-energy and Q-thruster devices are conserving energy if the inertial field and Universe mass is brought into play”

If the universe is expanding, then its mass must be increasing, and its energy must also be increasing.  If that is true, and a way can be figured out how to tap this increasing energy, then the effect would be to slow down the expansion of the universe.  But if there is an "inertial wind", then lo!  I am right in believing in the ether.

For example, I just got out of my chair and jumped up and down several times on the local planetary body, changing the universe ever so slightly, but changing it nevertheless.

Spare me the lesson about barycenters.  What I did is send out a rhythm of gravity waves which changes the inertial field of the same universe.

Point being, if this energy source could be tapped, it wouldn't change the universe all that much, at least at first.

Question being, can this be explained to a reasonably intelligent person?  Who might be an investor?  Right now, all of the explanations sound like those reporters who pestered Barry Goldwater.

OK. no barycenter arguments.  It has been supposed there are gravity waves even in the one-man-jumping case, just too small to measure. 

Personally, I'd love for the thing to actually work somewhere above the 10s of millinewtons per watt level: at 10 mN/W, at the kilowatt level, this baby would make a hęll of a space thruster.  Not much for power generation down here.  That takes closer to newtons per watt, not millinewtons.   But the thought remains the same: if it works, well let's just rewrite physics in a simple enough way so that it can be taught to high-school physics newbies.

After all, the totality of Einstein's Special Relativity (a 50+ page paper) can be boiled down to about 10 equations, of which one is particularly memorable.  E = mc˛

GoatGuy

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