Author Topic: EM Drive Developments - related to space flight applications - Thread 7  (Read 1707118 times)

Offline Vesc

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Or the effect is a mirage of poor error analysis. But the people arguing that have largely left this thread.
I would say that

1) most discussions here involve NO statistical error analysis, rather than "poor error analysis".  Comparisons are often made without any statistical error analysis. "Good error analysis" is not feasible (from the data I have seen so far) because the EM Drive experimental sample population is too small to even properly define what is the actual statistical distribution.  Notice the absence of histograms in experimental reports.

This is an excellent point. In case this hasn't sunk in, I would strongly encourage those DIY'ers that are actively conducting experiments [you know who you are  ;)] to conduct MULTIPLE test runs using exact same set ups and record ALL results, even if they appear to disagree with each other. You might at first blush think of this as a waste of time but it's all good, believe me.  And its much much easier to do it when the experiment is up and running than to go back and attempt it later as an afterthought. Because even that can introduce additional variables in the experiment.

Another caution, the temptation is to reject the data from experiment that doesn't either, 1) depending upon your own bias 1.1) yields a positive result and must be wrong and thrown away 1.2) yields a negative result ergo must be wrong and thrown away  and 2) appears to be an outlier. At this point in the research there is no such thing as an outlier (see previous posts from Dr. Rodal on non-linearity).

I am but a humble engineer who has only done statistical data sampling in a limited number of cases needed for performance analysis and have on rare occasion had to deal with 3 sigma mathematics etc. And these are only two recommendations for those doing experiments. I encourage other folks who've dealt much more closely with the mathematics and best practices for scientific experimentation to please chime in here as well, unless this issue has been addressed in a previous thread. Sorry if that's the case but there are 7 threads each of >100 posts and I haven't time now to go through them all.
« Last Edit: 04/28/2016 08:45 pm by Vesc »

Offline rfmwguy

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EMDrive talk on "new age" science show starts about 29 minutes in. NSF and Chris Bergin get a plug @ about 33 minutes in.


I'm very involved with TMRO and have been a guest 6 times.  I was at Hershey Park on Saturday.  I'm quite embarrassed for them, this show was not up to their usual standard - they didn't even pronounce 'magnetron' correctly.

It's not really 'new age' science, it's mostly space and space news (where they do have expertise).

I am, in fact, here on the forum because they asked me to do a short video on the EMDrive last August.  It's taken me until about now to be able to understand most of the physics discussed here :)  I'm going to respond to their show, probably with a short video which I hope will get played next week...
Thanks Emory...new age as in younger, more hip science shows I guess is what I was thinking  8)

Great! Feel free to download any of my youtube clips if you need some filler. Here they are:

https://www.youtube.com/channel/UCm54FS3u2aDeutnMsV0cITg/videos

Royalty free as well ::) Give us a peek at the vid if you get the chance. - Dave
« Last Edit: 04/28/2016 12:35 am by rfmwguy »

Offline Notsosureofit

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UPDATE:  Looking for a reliable data point for illustration

The first (and only ?) good number I've come across is from: https://forum.nasaspaceflight.com/index.php?topic=39214.10;wap2 (@RODAL and @XRAY)

"Based on this measurement data I've got a look to my calculated frequency for this case and find:

Mode  calculated(GHz) Comsol(GHz)  measured NASA(GHz) 
TE012   2.1653438127    2.1794       2.167138 
"
and
"I think that NASA built the truncated cone cavity to within measurement tolerances of +/-0.01” , giving internal dimensions as follows

bigDiameter = (11.00")  +/-0.01” ---> total % error = 0.18% = 1/550
smallDiameter = (6.25")  +/-0.01”--->total % error = 0.32% = 1/313
axialLength = (9")  +/-0.01” --->         total % error = 0.22% = 1/450

Therefore (taking the median total % error = 0.22% = 1/450) the dimensional tolerance of NASA's frustum is such that it is only for a Q<450 that one can hope to be within the resonant bandwidth, given the uncertainty due to dimensions ( 1/450)."

[Excuse my lousy editing]

To show what I'm trying to get at, the "0 entropy change from a cylindrical cavity" frequency should be 2.10575 GHz, 2.7% lower than the measured frequency and outside of the  0.22% error band.

The implication (or what I was hoping to illustrate w/ further data) is that this frustum cavity electromagnetic resonance shows a lower than expected entropy than the usual General Relativistic "constant volume" criteria.

Sorry if this isn't clearer but my time is severely limited at the moment.

 

Offline VAXHeadroom

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EMDrive talk on "new age" science show starts about 29 minutes in. NSF and Chris Bergin get a plug @ about 33 minutes in.


I'm very involved with TMRO and have been a guest 6 times.  I was at Hershey Park on Saturday.  I'm quite embarrassed for them, this show was not up to their usual standard - they didn't even pronounce 'magnetron' correctly.

It's not really 'new age' science, it's mostly space and space news (where they do have expertise).

I am, in fact, here on the forum because they asked me to do a short video on the EMDrive last August.  It's taken me until about now to be able to understand most of the physics discussed here :)  I'm going to respond to their show, probably with a short video which I hope will get played next week...
Thanks Emory...new age as in younger, more hip science shows I guess is what I was thinking  8)

Great! Feel free to download any of my youtube clips if you need some filler. Here they are:

https://www.youtube.com/channel/UCm54FS3u2aDeutnMsV0cITg/videos

Royalty free as well ::) Give us a peek at the vid if you get the chance. - Dave

I was actually going to suggest they have you on as a guest for a follow-up show :D
Emory Stagmer
  Executive Producer, Public Speaker UnTied Music - www.untiedmusic.com

Offline rfmwguy

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EMDrive talk on "new age" science show starts about 29 minutes in. NSF and Chris Bergin get a plug @ about 33 minutes in.


I'm very involved with TMRO and have been a guest 6 times.  I was at Hershey Park on Saturday.  I'm quite embarrassed for them, this show was not up to their usual standard - they didn't even pronounce 'magnetron' correctly.

It's not really 'new age' science, it's mostly space and space news (where they do have expertise).

I am, in fact, here on the forum because they asked me to do a short video on the EMDrive last August.  It's taken me until about now to be able to understand most of the physics discussed here :)  I'm going to respond to their show, probably with a short video which I hope will get played next week...
Thanks Emory...new age as in younger, more hip science shows I guess is what I was thinking  8)

Great! Feel free to download any of my youtube clips if you need some filler. Here they are:

https://www.youtube.com/channel/UCm54FS3u2aDeutnMsV0cITg/videos

Royalty free as well ::) Give us a peek at the vid if you get the chance. - Dave

I was actually going to suggest they have you on as a guest for a follow-up show :D
No problem, been interviewed on the radio 3 times with EMDrive...have Skype will travel.

Offline Rodal

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UPDATE:  Looking for a reliable data point for illustration

The first (and only ?) good number I've come across is from: https://forum.nasaspaceflight.com/index.php?topic=39214.10;wap2 (@RODAL and @XRAY)

"Based on this measurement data I've got a look to my calculated frequency for this case and find:

Mode  calculated(GHz) Comsol(GHz)  measured NASA(GHz) 
TE012   2.1653438127    2.1794       2.167138 
"
and
"I think that NASA built the truncated cone cavity to within measurement tolerances of +/-0.01” , giving internal dimensions as follows

bigDiameter = (11.00")  +/-0.01” ---> total % error = 0.18% = 1/550
smallDiameter = (6.25")  +/-0.01”--->total % error = 0.32% = 1/313
axialLength = (9")  +/-0.01” --->         total % error = 0.22% = 1/450

Therefore (taking the median total % error = 0.22% = 1/450) the dimensional tolerance of NASA's frustum is such that it is only for a Q<450 that one can hope to be within the resonant bandwidth, given the uncertainty due to dimensions ( 1/450)."

[Excuse my lousy editing]

To show what I'm trying to get at, the "0 entropy change from a cylindrical cavity" frequency should be 2.10575 GHz, 2.7% lower than the measured frequency and outside of the  0.22% error band.

The implication (or what I was hoping to illustrate w/ further data) is that this frustum cavity electromagnetic resonance shows a lower than expected entropy than the usual General Relativistic "constant volume" criteria.

Sorry if this isn't clearer but my time is severely limited at the moment.

 

QUESTIONS:

1) what is the support for the statement that  "0 entropy change from a cylindrical cavity frequency should be 2.10575 GHz, 2.7% lower than the measured frequency".  What equation(s) is(are) used to calculate this 2.10575 GHz frequency, which differs by 2.7% from the measured and calculated natural frequencies ?

2) Is the 2.7% difference between the 2.10575 GHz frequency and the measured and calculated natural frequencies for the truncated cone due to the fact that the 2.10575 GHz frequency is calculated for a cylindrical cavity while the actual cavity is instead a truncated cone?

PS:  For reference, here are links to posts with data supporting the calculated natural frequencies and the experimental measurements, showing the very high quality of NASA's measurements, that fully support the fact that the experiment by NASA without a polymer insert was indeed in resonance at  2.16 GHz, although the measured anomalous force was insignificant, even at 10 times higher power input than the tests with the polymer insert:

http://forum.nasaspaceflight.com/index.php?topic=39214.msg1469866#msg1469866

http://forum.nasaspaceflight.com/index.php?topic=39214.msg1470390#msg1470390

http://forum.nasaspaceflight.com/index.php?topic=39214.msg1470613#msg1470613

http://forum.nasaspaceflight.com/index.php?topic=39214.msg1473238#msg1473238

http://forum.nasaspaceflight.com/index.php?topic=39214.msg1473323#msg1473323

http://forum.nasaspaceflight.com/index.php?topic=39214.msg1473726#msg1473726

http://forum.nasaspaceflight.com/index.php?topic=39214.msg1473849#msg1473849

(and several other posts between them)
« Last Edit: 04/28/2016 03:13 pm by Rodal »

Offline rfmwguy

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Emidio Laureti has been patiently posting in the "other" forum, his experimental results and explanations for his PNN Q-Thruster.  Unfortunately his discussions are  met by name-calling and vituperations, without calculations, without using mathematical analysis (which are the hallmark of Physicists and Engineers, instead of using words and "laws").

I wonder whether Emidio Laureti could post here instead, where he may be met with strong objective criticism, but it would be moderated so that the criticism is scientific, focusing on experiments and calculations, instead of vituperations and name calling.  It is encouraging that Emidio's reaction to vituperation has been to use a gentle sense of humor and he has not been defensive at all, so it may be worthwhile to have a discussion with him that is free of invectives, and concentrates instead on his PNN experiments from a scientific viewpoint instead.

These are the 2015 claims for the PNN F242 performance:

•   Force: 600uN (with a tolerance of +- 100uN)
•   Input power 150W
•   Force/InputPower = 4 mN/kW (comparable to NASA TM212 2014 report, and to Iulian Berca's results)
Still, much lower than Cannae Superconducting, and Yang's non-superconducting EM Drive claimed 1,000 mN/kW

Here: https://neolegesmotus.wordpress.com/2016/04/24/f242-is-now-at-2-56-grams-of-thrust/

2.56 grams of thrust (25 milliiNewtons) are claimed at 180 W, in 2016, which gives:

•   Force/InputPower = 139 mN/kW
which is comparable to Shawyer's Demonstrator and Flight Thruster, but still below Yang's claims.


Also, he claims that PNN F242 is 10 times lighter than the EmDrive.  Not clear what are his assumptions in this regard.

Don't know why the contraption features a red cross pattιe. The form appears very early in medieval art, for example in a metalwork treasure binding given to Monza Cathedral by Queen Theodelinda (d. 628),  queen of the Lombards in Italy, and is often associated with the Crusades, sometimes used by the Teutonic Knights, and the Knigths Templar.


Hi Doc, this is enough of a unique device that it probably warrants its own thread, like the other one. That way, if it works out fine, if not, fine. Feel free to start it or I can when I get more time. We can then link to it here.

Offline Rodal

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...
Hi Doc, this is enough of a unique device that it probably warrants its own thread, like the other one. That way, if it works out fine, if not, fine. Feel free to start it or I can when I get more time. We can then link to it here.
Do you have information as to the details of PNN F242 to indicate that this is a unique device?

Not sure about that.  I was told by somebody in the Aerospace Industry (that wants to remain anonymous) that this PNN F242 may also be a resonant cavity thruster, as it was described -not by the inventor- in that closed conference as the "Italian EM Drive", and they gave other information, that I don't recall. 

Also notice its performance is similar to experimentally reported performance for other EM Drives (in terms of force, input Power, and in terms of force/InputPower), the inventor chose to join "the other EM Drive forum", and the inventor wears a metal shield, as if as to protect himself from escaping (microwave ?) radiation.

If it is a resonant cavity thruster, and it is "the Italian EM Drive" it seems logical that it should be discussed in this thread, just like the Cannae device is being discussed in this thread (actually the Cannae device shape may be more different from Shawyer's truncated cone, than this device). 

Of course, unless the inventor discloses whether this device is a resonant (closed or partially open) cavity thruster, or an electromagnetic Q thruster, and further details, there is not enough material to justify any further discussion either here or on its own thread (and yes, NSF members are always free to start other threads). 

IMHO discussion is moot unless the inventor joins NSF and is willing to share technical details.
« Last Edit: 04/28/2016 02:01 pm by Rodal »

Offline Monomorphic

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IMHO discussion is moot unless the inventor joins NSF and is willing to share technical details.

They mention using a dialectric!  ;D


Offline Rodal

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IMHO discussion is moot unless the inventor joins NSF and is willing to share technical details.

They mention using a dialectric!  ;D
Do you have a source for that information?
Is that information for PNN F242 or for an earlier Q-Thruster?
Is it a resonant (partially open or closed) cavity thruster operating at MHz or GHz frequencies?

Thanks
« Last Edit: 04/28/2016 02:02 pm by Rodal »

Offline Monomorphic

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Do you have a source for that information?
Is it a resonant (partially open or closed) cavity thruster operating at MHz or GHz frequencies?

Thanks

There is more technical information scattered around on hard-to-follow web pages that must be translated to english. Here is the one I was referring to. http://www.asps.it/

"Experimental adaptation of theoretical principle thrust shown in fig.D2. The white matter between the discs is a dielectric."

 
« Last Edit: 04/28/2016 02:05 pm by Monomorphic »

Offline Monomorphic

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Is that information for PNN F242 or for an earlier Q-Thruster?
Is it a resonant (partially open or closed) cavity thruster operating at MHz or GHz frequencies?
Thanks

This is info for the PNN F242. Here is another page: http://www.calmagorod.org/pnn-la-sua-genesi/

Offline Rodal

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Is that information for PNN F242 or for an earlier Q-Thruster?
Is it a resonant (partially open or closed) cavity thruster operating at MHz or GHz frequencies?
Thanks

This is info for the PNN F242. Here is another page: http://www.calmagorod.org/pnn-la-sua-genesi/
Thank you, I had not seen that information.  From what I can gather from the Italian text this looks more like a Q-thruster after Prof. Woodward's Mach Effect capacitor/dielectric designs, rather than a resonant microwave cavity, since it involves capacitors and dielectrics: involving 3 armature discs which define a top capacitor and a bottom capacitor. The two capacitors are fed with a variable potential.  Therefore it may be explained through Woodward's theory and perhaps White's QV as well.

According to this information, this is where I would place PNN F242 in the set of Q-thrusters:

See: http://forum.nasaspaceflight.com/index.php?topic=39772.msg1525268#msg1525268
« Last Edit: 04/28/2016 03:18 pm by Rodal »

Offline MrFrankenverse

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Offline Flyby

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This is info for the PNN F242. Here is another page: http://www.calmagorod.org/pnn-la-sua-genesi/
That calmagorod-experiment has been posted inhere about 12-18 months ago on this forum.

Offline Rodal

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This is info for the PNN F242. Here is another page: http://www.calmagorod.org/pnn-la-sua-genesi/
That calmagorod-experiment has been posted inhere about 12-18 months ago on this forum.
Was it posted by the inventor (Emidio Laureti) ? Any further info you can recall ?
« Last Edit: 04/28/2016 03:01 pm by Rodal »

Offline flux_capacitor

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There is more technical information scattered around on hard-to-follow web pages that must be translated to english. Here is the one I was referring to. http://www.asps.it/

"Experimental adaptation of theoretical principle thrust shown in fig.D2. The white matter between the discs is a dielectric."

Yes, as Rodal pointed out this is not a resonant cavity. The discs are conductive plates and the sandwiched dielectrics are there mainly to prevent electrical breakdown between plates, and hopefully to generate some sort of reactionless thrust force in an unknown combination with the pulsed HV electric and/or magnetic fields.

It reminds me a lot more of Serrano's Field Propulsion Thruster rather than Woodward's METs (edit: former MLTs).

Since Serrano's experiments used high voltage and were conducted without Faraday cage at ambient air pressure, they still remain inconclusive. Corona discharges and ion wind become the largest effect with these devices (including the old Biefeld-Brown asymmetric capacitors and more recently the ionocraft/lifter experiments).
« Last Edit: 04/28/2016 03:26 pm by flux_capacitor »

Offline Rodal

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There is more technical information scattered around on hard-to-follow web pages that must be translated to english. Here is the one I was referring to. http://www.asps.it/

"Experimental adaptation of theoretical principle thrust shown in fig.D2. The white matter between the discs is a dielectric."

Yes, as Rodal pointed out this is not a resonant cavity. The discs are conductive plates and the sandwiched dielectrics are there mainly to prevent electrical breakdown between plates, and hopefully to generate some sort of reactionless thrust force in an unknown combination with the pulsed HV electric and/or magnetic fields.

It reminds me a lot more of Serrano's Field Propulsion Thruster rather than Woodward's METs.

Since Serrano's experiments used high voltage and were conducted without Faraday cage at ambient air pressure, they still remain inconclusive. Corona discharges and ion wind become the largest effect with these devices (including the old Biefeld-Brown asymmetric capacitors and more recently the ionocraft/lifter experiments).

Excellent point, so we now move PNN F242 to the set intersecting the Serrano Field Effect thruster.
This also agrees with the statement that PNN F242 is said to be lighter than the EM Drive, which would agree with it being more akin to the Serrano thruster than to a Mach Lorentz Woodward thruster.
« Last Edit: 04/28/2016 03:21 pm by Rodal »

Offline OttO

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How Current Loops and Solenoids Curve Space-time
http://arxiv.org/pdf/1504.00333v3.pdf

What does it give mixed with some theories of the EM thruster? That is the question  :P

Offline Rodal

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How Current Loops and Solenoids Curve Space-time
http://arxiv.org/pdf/1504.00333v3.pdf

What does it give mixed with some theories of the EM thruster? That is the question  :P
Unfortunately it is shown in the paper that this is an extremely weak effect:  a superconducting coils field of 20 T would produce an effect that would take over 200 days to accumulate enough phase shift to be equivalent to the very weak signal received on Earth of a distant gravitational wave  :(
« Last Edit: 04/28/2016 03:32 pm by Rodal »

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