EM Drive Developments - related to space flight applications - Thread 7

[X_RaY]

Yes it's great news in scientifically sense and of course outstanding to publish this result and clear up / relativate  the older one.

It may help to exclude some theories as potential false.

[CW]

Yes it's great news in scientifically sense and of course outstanding to publish this result and clear up / relativate  the older one.

It may help to exclude some theories as potential false.

.. I always wondered from the beginning, as to why not everyone was designing their experiments to be self-contained. This is, I think, structurally the same problem as with over-unity claims. Close the loop, and if more energy comes out than is used, you got yourself a Nobel Prize. Didn't happen, though .

Great result and publication. So! future builds better be fully self-contained, is the message.

[Rodal]

Yes it's great news in scientifically sense and of course outstanding to publish this result and clear up / relativate  the older one.

It may help to exclude some theories as potential false.

.. I always wondered from the beginning, as to why not everyone was designing their experiments to be self-contained. This is, I think, structurally the same problem as with over-unity claims. Close the loop, and if more energy comes out than is used, you got yourself a Nobel Prize. Didn't happen, though .

Great result and publication. So! future builds better be fully self-contained, is the message.

The Hackaday Aachen Germany team is to be congratulated for designing their experiment to be self-contained from the beginning: it is battery powered.

Shawyer, not so much: decades of promoting the EM Drive: without a single test that is battery-powered self-contained, not a single test in a torsional pendulum and not a single test in a vacuum chamber.

Fetta's Cannae drive is also interesting as their latest test seem to be in a torsional pendulum, and it provides a bell jar for vacuum testing.  Does it have battery power ?  It says Li-ion vacuum battery power sources.

This is Cannae’s torsion pendulum thrust measurement equipment. It is designed to measure non-superconducting thruster forces from 2 uN up to 3000 uN. We have some unique features built into our equipment including liquid metal contacts which can be disengaged during test runs, laser micrometer and irradiance meter displacement sensors, Li-ion vacuum battery power sources, and high voltage operational capability. The whole test apparatus is located in a 36 inch diameter vacuum chamber base (visible in the picture). The bell-jar top of the chamber is not pictured here. We will be running additional vacuum chamber testing this week, and will place a picture of the assembled chamber in a future post.

In this picture is the Cannae thruster which was tested at NASA JSC in 2013 and reported on by NASA JSC at the 2014 AIAA Joint Propulsion Conference. Cannae has additional thruster designs that we are demonstrating in this test equipment.

[SeeShells]

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 

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

This latest paper by Prof. Yang nullifying her previous results present a great opportunity for you to announce in your appearance in this upcoming program at TMRO!

As these news have not yet been publicized in the media

These are the biggest news on EM Drive in several years !

How can you write such a definitive statement relating it to fact with the Chinese null test when you didn't give as much credence to the positive thrust events?

I believe we need to temper our enthusiasm in both tests where they showed thrusts and when they did not. It's quite hard to verify that this was indeed her results and we need to be as skeptical of the positive tests as we were treat the negative the same way. Truly more independent data is needed.





I'm going to say that this isn't a definitive test because of unknowns until more verifiable data is forthcoming.

I thought that I justified this in my prior posts. But here it goes again:

1) Second time, after Brito, Marini and Galian that a researcher nullifies their previous claims.  Done by using torsional pendulum and self-powered battery-operated.  It shows that scientists can and will publish experiments nullifying their previous results because scientists are interested in finding what is the truth. Having Prof. Yang publish a paper that nullifies her life work is undeniably, objectively, powerful.

2) All tests performed in teeter-totters and scales, and moreover having a power cord for energy supply have to be disregarded, in light of these results.   For more than 50 years it has been known in Aerospace R&D that the instrument of choice for micro-thrust experiments is the torsional pendulum.  For centuries it has been known that the sensitive instrument to measure G is the torsional pendulum. 

3) Since the 19th century it has been known that radiation pressure experiments are contaminated by thermal convection.

4) One doesn't get to run a power cord from the Earth to a spacecraft in space.  Tests that supply power from a stationary source by a cord to a moving EM Drive (instead of using self-integrated batteries) are questionable.   Conservation laws mean that the power source and its cables must be taken into account, and one does not get to hide it and ignore it from consideration under a curtain. The cables not only because of their electromagnetic effects but also because of their thermal expansion, as discussed by TellMeAgain above.

It is true that running power wires to a magnetron where Lorentz actions have to be taken into effect an can create false measurements but also realize that I didn't run power cables to the frustum magnetron. My magnetron was shielded (thermally and EM isolated) and away from the fustrum. I used highly flexible coaxial cable to an antenna.

Please note, in a coaxial cable the electromagnetic field carrying the signal exists only in the space between the inner and outer conductors.
http://ecee.colorado.edu/~ecen3400/Textbook/Chapter%2012%20-%20Magnetic%20Field%20in%20a%20Vacuum.pdf
Please reference: Chapter 12 page 196 of coaxial Lorentz forces that equate out to effectively zero and there is no magnetic field outside of the cable.

The only thing that becomes a issue would be the thermal expansion of the coaxial cable providing a potential bending moment to a beam if using a teeter/todder beam and that component can be addressed with the layout of the coax.

There are issues with a balance beam measurement I'll not argue with that.

To that I started a week ago in laying out the test bed to operate as a balance beam and the entire test bed and frustum as a single unit rotated 90 degrees to become a torsional pendulum. It will be interesting to measure both and compare data.

[CW]

(..)

The Hackaday Aachen Germany team is to be congratulated for designing their experiment to be self-contained from the beginning: it is battery powered.

(..)

One word: Germans.

SCNR

[X_RaY]

..snip
It will be interesting to measure both and compare data.

Great idea. I looking forward to see the results of this comparison. 

[rfmwguy]

Generally speaking, I think it is incorrect to make too many speculative statements or suggestions on the test stand. The paper seemed to conclude thermal expansion of the waveguide. Nothing more. Nothing less. Advocacy of self-containment is premature regarding power wires. 2 different things here...thermal expansion and lorentz force. Higher mass of self contained power unit created the less sensitive 3 wire torsion test. As mr li said, this is not ideal. Whether or not diy is in the same league as a funded university is irrelevant. Until more western universities gain interest or lose their fear, we have one paper which falsifies its own prior test. mr li's paper will guide us on lorentz mitigation...yang's on thermal expansion. These are the types of bonifide inputs that are required moving forward.

[Rodal]

Generally speaking, I think it is incorrect to make too many speculative statements or suggestions on the test stand. The paper seemed to conclude thermal expansion of the waveguide. Nothing more. Nothing less. Advocacy of self-containment is premature regarding power wires. 2 different things here...thermal expansion and lorentz force. Higher mass of self contained power unit created the less sensitive 3 wire torsion test. As mr li said, this is not ideal. Whether or not diy is in the same league as a funded university is irrelevant. Until more western universities gain interest or lose their fear, we have one paper which falsifies it own prior test. mr li's paper will guide us on lorentz mitigation...yang's on thermal expansion. These are the types of bonifide inputs that are required moving forward.

The audience can be the judge of what statements are speculative.

Prof. Yang's latest paper is not "one paper which falsifies it own prior test".  Instead it is a paper about at least new 20 tests with a much better designed testing instrument, that nullifies her entire previous series of tests that were performed with an inferior testing instrument. It most importantly nullifies her prior tests by incorporating battery power and hence eliminating the power cord.  The need of which I have been writing about for several posts, prior to Yang's report.

My statements are not suggestions for what you may or may not do, as I am only interested in addressing the subject of this thread: EM Drive Developments - related to space flight applications (*)

I am not addressing or suggesting anything for your tests because I am not clear as to how your tests relate to EM Drive Developments - related to space flight applications, as in spaceflight applications there is no power cord running from the Earth to a spacecraft, as in your tests. In contrast, tests like Hackaday's Aachen team's and the new Cannae testing device address spaceflight applications by being battery-powered.

And the experience of institutional research for 50 years in micro-thruster for spaceflight is that the proper instrument to use for testing micro-thrusters is a torsional pendulum instead of a teeter-totter.   Tests by NASA, Tajmar, and the new test by Yang address spaceflight applications by using the instrument of choice in Aerospace testing of micro-thrusters: the torsional pendulum.

Also I am not suggesting anything about your tests, as I am not clear as to how your tests relate to EM Drive Developments  - related to space flight applications, as in space there is a vacuum (or a partial vacuum in LEO) and your tests are performed at ambient condiitons.  In contrast, tests by NASA and Tajmar address spaceflight applications by performing their tests in a partial vacuum.
__________________
(*) Remember, this is a space flight site

EM Drive Developments - related to space flight applications - Thread 2
« on: 12/12/2014 11:40 AM »
Like
Thread 1:
http://forum.nasaspaceflight.com/index.php?topic=29276.0

Problems with Thread 1 explained (note the things to avoid in the new thread):
http://forum.nasaspaceflight.com/index.php?topic=29276.msg1301657#msg1301657

Thus Thread 2, with more focus on space flight applications to ensure this can have a healthy home here. Remember, this is a space flight site.

[ThinkerX]

So, if I am following this correctly, then...

Yang's results nullify any thrust from her devices greater than 3Mn - roughly on a par with other experiments.

The thrust *might* even be less than that, given the margin of uncertainty.  That margin might also allow for *slightly* larger results. 

Is that a fair assessment?  Seeking clarity here. 

But assuming 3Mn worth of thrust, give or take, is being produced somehow, then...

1 - does the EM Drive still stand in serious violation of CoE and CoM if the self contained version can produce 3Mn worth of thrust in a vacuum? 

2 - Would 3Mn worth of thrust be useful for spacecraft?

[rfmwguy]

So, if I am following this correctly, then...

Yang's results nullify any thrust from her devices greater than 3Mn - roughly on a par with other experiments.

The thrust *might* even be less than that, given the margin of uncertainty.  That margin might also allow for *slightly* larger results. 

Is that a fair assessment?  Seeking clarity here. 

But assuming 3Mn worth of thrust, give or take, is being produced somehow, then...

1 - does the EM Drive still stand in serious violation of CoE and CoM if the self contained version can produce 3Mn worth of thrust in a vacuum? 

2 - Would 3Mn worth of thrust be useful for spacecraft?

You have it basically. They moved from balance to torsion whose low end was 3mN. Don't think anything was measured, meaning it was nothing or below measurement threshold. 3 mN would be useful for spaceflight if it was this...all we know from her paper is it was below threshold of test stand and at around 275 watts of power. This was reported to be identical device tested originally. Coe and com are still unresolved. Dresden univ is offering phd project on emdrive, they will be moving forward as well.

[rfmwguy]

Generally speaking, I think it is incorrect to make too many speculative statements or suggestions on the test stand. The paper seemed to conclude thermal expansion of the waveguide. Nothing more. Nothing less. Advocacy of self-containment is premature regarding power wires. 2 different things here...thermal expansion and lorentz force. Higher mass of self contained power unit created the less sensitive 3 wire torsion test. As mr li said, this is not ideal. Whether or not diy is in the same league as a funded university is irrelevant. Until more western universities gain interest or lose their fear, we have one paper which falsifies it own prior test. mr li's paper will guide us on lorentz mitigation...yang's on thermal expansion. These are the types of bonifide inputs that are required moving forward.

The audience can be the judge of what statements are speculative.

Prof. Yang's latest paper is not "one paper which falsifies it own prior test".  Instead it is a paper about at least new 20 tests with a much better designed testing instrument, that nullifies her entire previous series of tests that were performed with an inferior testing instrument.

My statements are not suggestions for what you may or may not do, as I am only interested in addressing the subject of this thread: EM Drive Developments - related to space flight applications (*)

I am not addressing or suggesting anything for your tests because I am not clear as to how your tests relate to EM Drive Developments - related to space flight applications, as in spaceflight applications there is no power cord running from the Earth to a spacecraft, as in your tests. In contrast, tests like Hackaday's Aachen team's and the new Cannae testing device address spaceflight applications by being battery-powered.

And the experience of institutional research for 50 years in micro-thruster for spaceflight is that the proper instrument to use for testing micro-thrusters is a torsional pendulum instead of a teeter-totter.   Tests by NASA, Tajmar, and the new test by Yang address spaceflight applications by using the instrument of choice in Aerospace testing of micro-thrusters: the torsional pendulum.

Also I am not suggesting anything about your tests, as I am not clear as to how your tests relate to EM Drive Developments  - related to space flight applications, as in space there is a vacuum (or a partial vacuum in LEO) and your tests are performed at ambient condiitons.  In contrast, tests by NASA and Tajmar address spaceflight applications by performing their tests in a partial vacuum.
__________________
(*) Remember, this is a space flight site

EM Drive Developments - related to space flight applications - Thread 2
« on: 12/12/2014 11:40 AM »
Like
Thread 1:
http://forum.nasaspaceflight.com/index.php?topic=29276.0

Problems with Thread 1 explained (note the things to avoid in the new thread):
http://forum.nasaspaceflight.com/index.php?topic=29276.msg1301657#msg1301657

Thus Thread 2, with more focus on space flight applications to ensure this can have a healthy home here. Remember, this is a space flight site.

I think chris bergin is fully aware that ground-based design and testing is required prior to spaceflight, which is every diyers goal to my knowledge. A lot of testing is with done with umbilicals. Since institutional testing is  nonexistant in the usa, less than ideal testing continues, or minor league testing as you infer...this commentary seems further off-topic than most here.

[Tellmeagain]

So, if I am following this correctly, then...

Yang's results nullify any thrust from her devices greater than 3Mn - roughly on a par with other experiments.

The thrust *might* even be less than that, given the margin of uncertainty.  That margin might also allow for *slightly* larger results. 

Is that a fair assessment?  Seeking clarity here. 

But assuming 3Mn worth of thrust, give or take, is being produced somehow, then...

1 - does the EM Drive still stand in serious violation of CoE and CoM if the self contained version can produce 3Mn worth of thrust in a vacuum? 

2 - Would 3Mn worth of thrust be useful for spacecraft?

You have it basically. They moved from balance to torsion whose low end was 3mN. Don't think anything was measured, meaning it was nothing or below measurement threshold. 3 mN would be useful for spaceflight if it was this...all we know from her paper is it was below threshold of test stand and at around 275 watts of power. This was reported to be identical device tested originally. Coe and com are still unresolved. Dresden univ is offering phd project on emdrive, they will be moving forward as well.

I think I am responsible to clarify that I did not read from the paper that "This was reported to be identical device tested originally". It is only that in the new paper, they tested two settings, that power was on board and that power was supplied from outside. The device was identical in these two settings. It was not mentioned whether the device was the same as 2008 (and I think not; because in 2008 paper they used magnetron and in 2016 paper they used solid state...)

 

 

[Rodal]

...
I think chris bergin is fully aware that ground-based design and testing is required prior to spaceflight, which is every diyers goal to my knowledge. A lot of testing is with done with umbilicals. Since institutional testing is  nonexistant in the usa, less than ideal testing continues, or minor league testing as you infer...this commentary seems further off-topic than most here.

Your statement that

Since institutional testing is  nonexistant in the usa, less than ideal testing continues

regarding the EM Drive is incorrect.  As Star-Drive remarked in a recent statement, NASA Eagleworks (NASA is an institution in the USA) experiments with Q-thrusters like the EM Drive are still taking place.

[Rodal]

So, if I am following this correctly, then...

Yang's results nullify any thrust from her devices greater than 3Mn - roughly on a par with other experiments.

The thrust *might* even be less than that, given the margin of uncertainty.  That margin might also allow for *slightly* larger results. 

Is that a fair assessment?  Seeking clarity here. 

But assuming 3Mn worth of thrust, give or take, is being produced somehow, then...

1 - does the EM Drive still stand in serious violation of CoE and CoM if the self contained version can produce 3Mn worth of thrust in a vacuum? 

2 - Would 3Mn worth of thrust be useful for spacecraft?

I discussed the statistics above, but to put this is in simpler terms:

1) Yang's latest tests nullify her prior test claims.  She achieves this by using a torsional pendulum using wires instead of her previous faulty instrument, and most importantly by using batteries instead of a power cord going to a stationary power supply.

2)

the EM Drive still stand in serious violation of CoE and CoM if the self contained version can produce 3Mn worth of thrust in a vacuum? 

  It depends on the power it takes to get the 3 mN thrust.  If the force/PowerInput is larger than the one of a perfectly collimated photon rocket, it violates Conservation of Energy.
If it self-accelerates when powered by batteries in a torsional Cavendish pendulum, without expelling mass or energy, and without being acted by external fields, then it is in violation of Conservation of Momentum, regardless of the Power Input, as much as the self-acceleration cannot be explained by those stated conditions.

For example: there is heat transferred from the EM Drive.  Such heat exchange will generate a self-acceleration. Violation of CoM is only for self-acceleration that cannot be explained by such classical effects.  Ditto for Lorentz forces covered by TellMeAgain. Ditto for thermal expansion forces covered in my initial post at NSF and by Prof. Frobnicat. Ditto for thermal expansion from the cables.

[ThinkerX]

Ok, would 3Mn worth of 'thrust' be in the ballpark range for the 'Not-so-sure-of-it' hypothesis?

[Rodal]

So, if I am following this correctly, then...

Yang's results nullify any thrust from her devices greater than 3Mn - roughly on a par with other experiments.

The thrust *might* even be less than that, given the margin of uncertainty.  That margin might also allow for *slightly* larger results. 

Is that a fair assessment?  Seeking clarity here. 

But assuming 3Mn worth of thrust, give or take, is being produced somehow, then...

1 - does the EM Drive still stand in serious violation of CoE and CoM if the self contained version can produce 3Mn worth of thrust in a vacuum? 

2 - Would 3Mn worth of thrust be useful for spacecraft?

You have it basically. They moved from balance to torsion whose low end was 3mN. Don't think anything was measured, meaning it was nothing or below measurement threshold. 3 mN would be useful for spaceflight if it was this...all we know from her paper is it was below threshold of test stand and at around 275 watts of power. This was reported to be identical device tested originally. Coe and com are still unresolved. Dresden univ is offering phd project on emdrive, they will be moving forward as well.

I think I am responsible to clarify that I did not read from the paper that "This was reported to be identical device tested originally". It is only that in the new paper, they tested two settings, that power was on board and that power was supplied from outside. The device was identical in these two settings. It was not mentioned whether the device was the same as 2008 (and I think not; because in 2008 paper they used magnetron and in 2016 paper they used solid state...)

Need help from TellMeAgain with translation from Chinese:

It seems that when the power source was kept separate from the microwave thruster, she measured anomalous force in the range of 8mN to 10.69mN and the uncertainty was between 9.2% and 3.3%.

However, when the power source was incorporated with the EM Drive the anomalous force measured was

uncertainty at 14% --> ± 3 mN
uncertainty at 80% --> ± 0.7mN

It looks like integrating the power source eliminating the power cord, to a stationary supply is of paramount importance.

Also the response seems very nonlinear: one cannot assume constant force/PowerInput

Is that a correct interpretation? Thanks

[otlski]

Since it is unlikely that a DIY'er would have access to a vacuum chamber, there might be another way forward.  An air tight tent could be erected around the experiment and testing would commence in air and repeatability established through say ten identical runs.  Next, change only the atmosphere inside the tent via bottled gas; try CO2, helium, argon, etc.  If the experiment were repeatable enough and the results did not change depending on the gas used, then you would have good justification for pleading for the use of a vacuum chamber.

If the results changed depending on gas then the results would be plotted and analysed to look for correlation with the varying properties of each gas (density, viscosity, etc.).  Doing so would point you to the path of your experimental error.

Proper safety would need to be observed.  Small bottles in large rooms are preferred.  O2 sensors employed.  Is the gas lighter then air or heavier?  If anyone thought this is perhaps a good next step after initial positive indications, we should discuss safety in more detail.  I have some experience on the safety side of this.  This is not quite an original idea; we have used air and helium atmospheres to measure the MOI of objects and extrapolated the results to a close match with vacuum.

[Tellmeagain]

Need help from TellMeAgain with translation from Chinese:

It seems that when the power source was kept separate from the microwave thruster, she measured anomalous force in the range of 8mN to 10.69mN and the uncertainty was between 9.2% and 3.3%.

Correct.

However, when the power source was incorporated with the EM Drive the anomalous force measured was

uncertainty at 14% --> ± 3 mN
uncertainty at 80% --> ± 0.7mN

the 3mN 14% thing is the property of the measure system. the 0.7mN 80% thing is about the measured self-contained device.

It looks like integrating the power source eliminating the power cord, to a stationary supply is of paramount importance.

Correct.

Also the response seems very nonlinear: one cannot assume constant force/PowerInput

I do not find this in their paper.

Is that a correct interpretation? Thanks

You are welcome.

[Rodal]

Need help from TellMeAgain with translation from Chinese:

It seems that when the power source was kept separate from the microwave thruster, she measured anomalous force in the range of 8mN to 10.69mN and the uncertainty was between 9.2% and 3.3%.

Correct.

However, when the power source was incorporated with the EM Drive the anomalous force measured was

uncertainty at 14% --> ± 3 mN
uncertainty at 80% --> ± 0.7mN

the 3mN 14% thing is the property of the measure system. the 0.7mN 80% thing is about the measured self-contained device.

...

Thank you very kindly for your answers and translation 

If I may impose on you once again, did they conduct 20 tests with batteries? how many tests were performed just with batteries (0.7mN 80%)?

(I am trying to make sense of her statistics concerning what she defines as "uncertainty", by performing my own estimates of uncertainty)

[Tellmeagain]

Thank you very kindly for your answers and translation 

If I may impose on you once again, did they conduct 20 tests with batteries? how many tests were performed just with batteries (0.7mN 80%)?

(I am trying to make sense of her statistics concerning what she defines as "uncertainty", by performing my own estimates of uncertainty)

Dr. Rodal, Yes, the with battery test was carried out with 20 repeats. You can find that out from Figure 18(a). Figure 18(b) is the same data after mapped with the fitted curve in Figure 14.