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#4080
by
SeeShells
on 31 Jul, 2016 17:08
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Beam calibration complete. 100mg test. Total displacement for 100mg was 0.857 Volts. Which is 0.00857 Volts/mg.
Maximum total displacement of powered test was 0.186 Volts. 0.186/0.00857 = 21.7mg
21.7mg = 0.0002128 N = 0.2128 mN = 212.8 μN
Are you planning to rotate the drive 90
o so it's main axis is in line with your beam?
Whatever you do, nice work and good data.
Shell
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#4081
by
sghill
on 31 Jul, 2016 18:11
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Did anyone see Space's Deepest Secrets "The Plot Against Gravity" tonight? Kind of a nice history of recent research in this area, EM Drive included, plus hints at some new ideas.
I watched the whole episode this morning. There were some very nice tidbits about 30 minutes into it:
They interview Shawyer and show one of his drives on an air bearing sliding around (but disconnected). Shawyer spends some nice air time clarifying his concept (nothing new, but it was nice to hear his speak).
They interview Tajmar and show a video of Tajmar testing a small replica of Shawyer's first EMDrive in a vacuum chamber. He spends a lot of on air time talking about his results.
They don't talk about Eagleworks, but they do an interview out at Glenn with the advanced propulsion director there. He talks a bunch about a new ion drive they are developing.
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#4082
by
RERT
on 31 Jul, 2016 19:05
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Shells - as stated above, it's easy to imagine an asymmetric body being subject to a couple in a vertical airflow due to non-uniform profile and therefore air resistance. I think it's reasonably intuitive (but not obvious to calculate) that twisting the frustrum/wedge about an axis parallel to the torsion arm will affect the arm, unless the frustrum is freely pivoted about its centre of gravity.
Monomorphic - analysing this stuff is hard, but one thing I'm sure of is that to assess whether a force is being applied by the EMDrive, we need to know how the system moves in the absence of force - the kernel solution, if you like. To that end, it would be great to see a long lead in (from cold) in your tests, so that we can have a crack at characterising the unforced motion. Whatever unforced oscillation you see, a few wavelengths worth would be great to have, of the longest wavelength visible.
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#4083
by
meberbs
on 31 Jul, 2016 22:35
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Beam calibration complete. 100mg test. Total displacement for 100mg was 0.857 Volts. Which is 0.00857 Volts/mg.
Maximum total displacement of powered test was 0.186 Volts. 0.186/0.00857 = 21.7mg
21.7mg = 0.0002128 N = 0.2128 mN = 212.8 μN
Congratulations, that is great sensitivity in your setup. What was the power level for your powered test?
The behavior after power off suggests that there is an error source on the order of your measured displacement. I will have to wait until you have had a chance to do some more tests before that can be analyzed. An extended plot after the test ends to see the level off at the original center position would be helpful.
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#4084
by
masterharper1082
on 01 Aug, 2016 04:12
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Beam calibration complete. 100mg test. Total displacement for 100mg was 0.857 Volts. Which is 0.00857 Volts/mg.
Maximum total displacement of powered test was 0.186 Volts. 0.186/0.00857 = 21.7mg
21.7mg = 0.0002128 N = 0.2128 mN = 212.8 μN
Congratulations, that is great sensitivity in your setup. What was the power level for your powered test?
The behavior after power off suggests that there is an error source on the order of your measured displacement. I will have to wait until you have had a chance to do some more tests before that can be analyzed. An extended plot after the test ends to see the level off at the original center position would be helpful.
I expect you will see that when the DUT cools back closer to room temperature. It would be one more piece of evidence showing that the thermally induced force is opposite in polarity to the anomalous force.
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#4085
by
meberbs
on 01 Aug, 2016 05:12
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Beam calibration complete. 100mg test. Total displacement for 100mg was 0.857 Volts. Which is 0.00857 Volts/mg.
Maximum total displacement of powered test was 0.186 Volts. 0.186/0.00857 = 21.7mg
21.7mg = 0.0002128 N = 0.2128 mN = 212.8 μN
Congratulations, that is great sensitivity in your setup. What was the power level for your powered test?
The behavior after power off suggests that there is an error source on the order of your measured displacement. I will have to wait until you have had a chance to do some more tests before that can be analyzed. An extended plot after the test ends to see the level off at the original center position would be helpful.
I expect you will see that when the DUT cools back closer to room temperature. It would be one more piece of evidence showing that the thermally induced force is opposite in polarity to the anomalous force.
This is the type of statement I explicitly avoided and said we need more data first. There is obviously at least one complicating factor. Without enough information to determine what it is, there could be 2 competing factors that vary with time or RF freq (what gets hot varies with whether it is in resonance), or one complicated factor that can change direction. The most useful path forward is to figure out what is happening and mitigate it. Analysis to "take out the bias" cannot be done without a very detailed understanding of what is happening.
Monomorphic's anomalous displacement is in the opposite direction of other experiments. It could even be that the swing back at RF off is actually the real anomalous force lingering and the part during power on was due to some other factor (such as Lorentz) that went away with power off. (not that I think this is the case) One of the best things the EMDrive had going for it was consistent direction. Most (not all) of the theories I have seen would not allow the direction to switch based on mode shape. Remember that there have been many, very accurate experiments supporting the standard physics that says the EMdrive should not work. That is why devices like this are at best considered a very long shot, and the device working as claimed is the least likely explanation for observed results unless other factors are controlled extremely well.
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#4086
by
masterharper1082
on 01 Aug, 2016 11:09
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Beam calibration complete. 100mg test. Total displacement for 100mg was 0.857 Volts. Which is 0.00857 Volts/mg.
Maximum total displacement of powered test was 0.186 Volts. 0.186/0.00857 = 21.7mg
21.7mg = 0.0002128 N = 0.2128 mN = 212.8 μN
Congratulations, that is great sensitivity in your setup. What was the power level for your powered test?
The behavior after power off suggests that there is an error source on the order of your measured displacement. I will have to wait until you have had a chance to do some more tests before that can be analyzed. An extended plot after the test ends to see the level off at the original center position would be helpful.
I expect you will see that when the DUT cools back closer to room temperature. It would be one more piece of evidence showing that the thermally induced force is opposite in polarity to the anomalous force.
This is the type of statement I explicitly avoided and said we need more data first. There is obviously at least one complicating factor. Without enough information to determine what it is, there could be 2 competing factors that vary with time or RF freq (what gets hot varies with whether it is in resonance), or one complicated factor that can change direction. The most useful path forward is to figure out what is happening and mitigate it. Analysis to "take out the bias" cannot be done without a very detailed understanding of what is happening.
Monomorphic's anomalous displacement is in the opposite direction of other experiments. It could even be that the swing back at RF off is actually the real anomalous force lingering and the part during power on was due to some other factor (such as Lorentz) that went away with power off. (not that I think this is the case) One of the best things the EMDrive had going for it was consistent direction. Most (not all) of the theories I have seen would not allow the direction to switch based on mode shape. Remember that there have been many, very accurate experiments supporting the standard physics that says the EMdrive should not work. That is why devices like this are at best considered a very long shot, and the device working as claimed is the least likely explanation for observed results unless other factors are controlled extremely well.
Everything you say here is good. Notice that I still called it anomalous force. Even if we understood the nature of the convection-induced thermal force perfectly, or eliminated it by a vacuum chamber (the best or final solution if not constrained by cost), all we would do is reduce our error bars - there is no guarantee of actual thrust. We could still be missing another error source.
Things to keep in mind:
- Changing the amount of power heating the DUT affects the rate of change of temperature of the DUT, not the temperature directly, via the thermal capacitance of the copper.
- The temperature of the DUT is stabilized by the feedback loop of convection and radiation induced heat transfer.
- Thermal processes typically act on time constants one or more orders of magnitude slower than electrical processes like Lorentz forces.
- It is reasonable (but not guaranteed as you allude to) that any real thrust force, if it exists, scales up and down with the amount of power applied to the resonating field, not applied to heating up the copper. One could reasonably expect that a real thrust force would act with a time constant more like an electrical system, rather than that of a thermal system.
Returning to the same state of the DUT (temperature and absence of applied power), should return to the same torsional balance force - over time, after accounting for dynamic effects from the torsional stiffness and moment of inertia. Any errors seen there are due to the limitations of the measurement apparatus and its external environment.
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#4087
by
rfmwguy
on 01 Aug, 2016 13:54
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Regardless of the direction of displacement, this is the second validation (including mine) of an opposite force when compared to thermal. The persistence and RTC will be good to validate the "upward" displacement (on the chart) is thermal. However, we are left with 2 main choices for this opposite-thermal displacement: Lorentz and Thrust. Jetting is unlikely as are most other error forces which would be responsible for such a dramatic and synchronized reaction to RL peak...except for one discussed below.
During peak "lock" Thermal heating will move from the mag to the cavity, and anode current should go down (remember plate dip tuning from the old days). So, Lorentz has a bit of a hill to climb since current should be minimum at "lock".
Now, we have another, probably less likely cause to investigate...(non-current induced) Magnetic. I say less likely because I measured no proximity spike in the Gauss field during power-on conditions. At one time I was wondering if the mag rings themselves were generating a field that turned the assembly into a "super compass". While not convinced this is happening, it is probably advisable to put this to bed with a simple 180 rotation of the test stand or cavity assembly to determine if the force remains and/or reverses.
Great job Jamie. Your design, build and test are first class DIY and an inspiration to others who have the skillset to tackle something so elusive. While the books may tell us this shouldn't be happening, the results are showing something different. If the displacement is truly something mundane, I'm sure DIY efforts will lead to the cause. Think the answer will be revealed in the hardware, not the books.
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#4088
by
tchernik
on 01 Aug, 2016 16:26
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Congratulations to Jamie and Dave for their latest results.
Things are going with a slower pace now, waiting for results for keeping the discussion alive, but they seem also way more interesting in retrospect, because the experiments are clearly improving and the number of artifacts is being reduced.
Those self-contained battery powered tests will be really telling.
Either confirmation or refutation of the claims would be astounding results. Because such results would have come from citizen scientists, something that unfortunately we see less and less often these days.
I'm allowing myself to remain optimistic, though, because some kind of thrust effect lingers.
A battery powered confirmation will keep this very much alive and going on, even if nobody expect these devices to lift themselves and go through the roof in self propelled mode anymore, the fact the phenomenon could be real and above a photon rocket is a potential revolution of implications we can't really fathom, and a potential new age in space exploration.
It only needs to be validated and find its way into space. Something some people seems to be already planning to do. At least the Aaschen guys and Cannae people seem like they want it.
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#4089
by
Mezzenile
on 01 Aug, 2016 20:46
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One more positive test result for the Shawyer device and the theory of Mc Culloch !!! Thank you very very much.
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#4090
by
meberbs
on 01 Aug, 2016 22:35
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One more positive test result for the Shawyer device and the theory of Mc Culloch !!! Thank you very very much.
There is no unbiased way to make this claim. As I stated above, there is obviously at least one complicating factor at the same strength as any potential signal. There is simply no way to make a claim of a positive (or negative) result based on the current data. Making such a claim is simply biased and unscientific
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#4091
by
Monomorphic
on 01 Aug, 2016 23:12
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I got tired of having to turn off the AC and move very slowly during experiments, so I built a structure around the torsional pendulum to shield it from unwanted air currents in the room. All construction is wood, hardboard, 3/4 inch foam, and brass screws. There will be two large clear-acrylic doors that open in the center front so it is still easy to access the emdrive and torsional pendulum. Hope to work on those tomorrow.
I used perforated hardboard at the top to allow warmer air to escape during tests. If need be, I will also have the ability to completely seal the chamber by placing 3/4 foam sheets over the holes, or removing the perforated hardboard and leave the top open.
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#4092
by
Torbjorn Larsson, OM
on 01 Aug, 2016 23:38
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One more positive test result for the Shawyer device and the theory of Mc Culloch !!! Thank you very very much.
There is no unbiased way to make this claim. As I stated above, there is obviously at least one complicating factor at the same strength as any potential signal. There is simply no way to make a claim of a positive (or negative) result based on the current data. Making such a claim is simply biased and unscientific
Besides which a scientific test would have to be peer reviewed published and repeated in order to be accepted. (C.f. LIGO with its two detectors.)
I went back to the first thread and I see a company, which must have been of age, was described as producing no results already 2011. If there is still no signal in the noise, it isn't even a technological test since it takes a few months to a year to establish a technology as viable or a dud from a demonstrator. [I wish I had a good reference but I'm not aware of any research on this. So it will stand as anecdotal for the time being.]
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#4093
by
WarpTech
on 02 Aug, 2016 00:24
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I got tired of having to turn off the AC and move very slowly during experiments, so I built a structure around the torsional pendulum to shield it from unwanted air currents in the room. All construction is wood, hardboard, 3/4 inch foam, and brass screws. There will be two large clear-acrylic doors that open in the center front so it is still easy to access the emdrive and torsional pendulum. Hope to work on those tomorrow.
I used perforated hardboard at the top to allow warmer air to escape during tests. If need be, I will also have the ability to completely seal the chamber by placing 3/4 foam sheets over the holes, or removing the perforated hardboard and leave the top open.
Cover the whole thing in plexiglass and get a small vacuum pump, and you're all set to eliminate air completely.
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#4094
by
TheTraveller
on 02 Aug, 2016 02:04
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I got tired of having to turn off the AC and move very slowly during experiments, so I built a structure around the torsional pendulum to shield it from unwanted air currents in the room. All construction is wood, hardboard, 3/4 inch foam, and brass screws. There will be two large clear-acrylic doors that open in the center front so it is still easy to access the emdrive and torsional pendulum. Hope to work on those tomorrow.
I used perforated hardboard at the top to allow warmer air to escape during tests. If need be, I will also have the ability to completely seal the chamber by placing 3/4 foam sheets over the holes, or removing the perforated hardboard and leave the top open.
Congratulations on your efforts to control the external enviroment. A very necessary step.
Now you need to get control of the freq, via single freq excitation, that auto tracks lowest VSWR. Using a maggie with uncontrolled splatter, unknown forward power and the maggie reflected and conversion losses radiating into the frustum side wall and into the adjacent air space is a uncontrolled mix of uncontrolled effects.
Even with no VSWR tracker, you can still manually adjust the frequency while tuning for lowest reflected power, feeding the frustum via coax, while the Rf amp and power supply are outside the controlled test chamber.
Doing this will eliminate so much crap and give you control of frustum excitation freq & mode, using a single adjustable freq AND while observing both forward & reflected. Using the 250W Rf amp chips should give you more than enough power to achieve around 100mN.
As others are building, your frustum needs to be able to continually accelerate, so back to your air bearing track or a battery powered rotary test rig.
It should be your next step, along with a proper TE013 frustum with spherical end plates.
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#4095
by
tleach
on 02 Aug, 2016 04:38
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First powered test with the TE203 wedge. I'm getting the same "reverse thrust" as seen with the TE311 frustum. 
Nothing has changed on the build except for the resonator itself. I even moved the entire test stand two feet further away from the masonry wall as it likely contains ferromagnetic rebar. I double-checked to make sure that less voltage in the graph is "reverse" (big end leading). I've performed two powered test now with very similar results.
Have you tried reversing the polarity?
https://www.youtube.com/embed/QDaCMhKPGys
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#4096
by
Tellmeagain
on 02 Aug, 2016 04:56
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A good experiment needs to control for confounding factors. I suggest monomorphic to include the following control experiment as marked on the picture.
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#4097
by
meberbs
on 02 Aug, 2016 05:03
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...
As others are building, your frustum needs to be able to continually accelerate, so back to your air bearing track or a battery powered rotary test rig.
Seriously? You are going to tell someone who has a setup that should be able to measure down to probably 50 microNewtons or less (if other complications can be controlled for) that they should abandon it?
A self contained battery powered setup is one of the most useful tests, but so is a torsional pendulum. Even better would be a battery powered device on a torsional pendulum. An air track can be good, but it won't have the same extreme sensitivity, and there are more complicating factors to deal with.
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#4098
by
TheTraveller
on 02 Aug, 2016 05:45
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...
As others are building, your frustum needs to be able to continually accelerate, so back to your air bearing track or a battery powered rotary test rig.
Seriously? You are going to tell someone who has a setup that should be able to measure down to probably 50 microNewtons or less (if other complications can be controlled for) that they should abandon it?
A self contained battery powered setup is one of the most useful tests, but so is a torsional pendulum. Even better would be a battery powered device on a torsional pendulum. An air track can be good, but it won't have the same extreme sensitivity, and there are more complicating factors to deal with.
In this setup, when the frustum stops moving, it might stop producing force. Depends on now much test rig & EmDrive vibration is occuring. The only way to properly measure EmDrive thrust is to allow continuous acceleration via the use of an air bearing suspension accelerative track, as Roger showed in the 2016 Horizon video or a rotary test rig as shown in the 2006 video or a similar test rig.
Please read and try to understand Roger's advise:
http://www.emdrive.com/EmDriveForceMeasurement.pdfThere are many ways to get this wrong & end up chasing shadows.
Blasting away with a wandering maggie splatter, forward & reflected power changing by the microsecond, mode excited changing as freq changes, location of frustum eddy currents and thus localised frustum heating versus maggie heating from conversion inefficiency plus reflected power heating turn the system into a literal dog's breakfast of so many competing effects as to make meaningful measurement almost impossible.
That Jamie has been able to show a thrust bandwidth, that aligns with VNA bandwidth is the biggest take away of his efforts to date. While I and one other have done this before, it is good to see Jamie likewise map his frustum's thrust bandwidth. Had he been able to use single freq excitation, he would have found the thrust bandwidth is actually narrower than the RL bandwidth.
Hard reality is these high Q frustums need to be excited by a single freq that tracks lowest VSWR. While playing with maggies is easy & low cost, there is no future down that pathway unless splatter can be controlled to say +-5kHz and even then Q needs to be limited and so specific thrust will be much less than very high Q single freq excitation.
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#4099
by
Tcarey
on 02 Aug, 2016 06:06
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I got tired of having to turn off the AC and move very slowly during experiments, so I built a structure around the torsional pendulum to shield it from unwanted air currents in the room. All construction is wood, hardboard, 3/4 inch foam, and brass screws. There will be two large clear-acrylic doors that open in the center front so it is still easy to access the emdrive and torsional pendulum. Hope to work on those tomorrow.
I used perforated hardboard at the top to allow warmer air to escape during tests. If need be, I will also have the ability to completely seal the chamber by placing 3/4 foam sheets over the holes, or removing the perforated hardboard and leave the top open.
Good modifications to your experimental setup. The air currents created by the maggie and frustum heat source should be mostly vertical in nature even in the case where you put the foam covers over the perf boards. I'm going to guess that you will set up a vertical circular air motion inside enclosure.
To visualize the air currents I suggest you get several "punks" or incense sticks and place them inside the enclosure to show what the air currents are. A punk, to those who don't play with fireworks, are the slow burning sparkler shaped sticks that are used to ignite small fireworks. They are basically incense sticks without the aroma and are very cheap. They burn slowly and give off a nice smoke column that is useful in detecting air leaks and air motion.
Your recent ADC improvements are real confidence builders in your data acquisition. Nicely done.
