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#200 by Flyby on 07 Jun, 2017 21:17
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No, not just someone... someone with high credibility, backed by good reputation and prior work. Otherwise you'd have to accept that people can easily soar up in the air based on what you see at a David Copperfield show. If NASA builds such a device and it does what you described above (as confirmed by other experts and space agencies), that would be "extraordinary evidence".
Dr.White filming their test stand in operation....
Granted, the short film was posted without approval/authorization (hence why it is so hard to find) but it is clear that "something" makes their setup move.(8.3 revolutions per hour, iirc)
What remains to do is to identify WHAT makes it move...
It might be vibrations, it might Lorentz forces, it might be thermal (less likely as they tried hard to eliminate that part in vacuum), or... it might be that there is indeed an EM effect that we have difficult to understand how it's working....
It is not something that hides in statistical data and can be endlessly debated on it validity. It turns, no question about that...
It now needs replication and it needs validation by elimination of all "other possible causes".
And that's exactly what Michelle, Jamie and Paul March are working on...
If only TT would provide more evidence and feedback then his name would be on top of the list too.
We all need patience, because solid testing needs a lot of preparation...hence time...specially when the budgets are limited... -
#201 by otlski on 07 Jun, 2017 23:57
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No, not just someone... someone with high credibility, backed by good reputation and prior work. Otherwise you'd have to accept that people can easily soar up in the air based on what you see at a David Copperfield show. If NASA builds such a device and it does what you described above (as confirmed by other experts and space agencies), that would be "extraordinary evidence".
Dr.White filming their test stand in operation....
Granted, the short film was posted without approval/authorization (hence why it is so hard to find) but it is clear that "something" makes their setup move.(8.3 revolutions per hour, iirc)
What remains to do is to identify WHAT makes it move...
It might be vibrations, it might Lorentz forces, it might be thermal (less likely as they tried hard to eliminate that part in vacuum), or... it might be that there is indeed an EM effect that we have difficult to understand how it's working....
It is not something that hides in statistical data and can be endlessly debated on it validity. It turns, no question about that...
It now needs replication and it needs validation by elimination of all "other possible causes".
And that's exactly what Michelle, Jamie and Paul March are working on...
If only TT would provide more evidence and feedback then his name would be on top of the list too.
We all need patience, because solid testing needs a lot of preparation...hence time...specially when the budgets are limited...
Perhaps it is EM drive effect as we all hope, or it could be any number of air bearing artifacts. I do remember mention of major issues with EW's bearing. I have designed, built, and tested many air bearings and can envision self-motoring and preferred position as suspect causes. Some time ago I looked over the data from EW associated with this test and there was no obvious smoking gun (artifact-wise). However, there are questions unanswered preventing me from concluding all was valid.
Shawyer's test on the other hand was fraught with issues. Mainly, he did not rotate more than 360 degrees and the attaching cables undermined the test.
Suffice to say I could put a pile of marshmallows on different types of air bearings and make them rotate via different techniques. My only point being that it is easy to accidentally create subtle rotation. -
#202 by SeeShells on 08 Jun, 2017 02:52
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No, not just someone... someone with high credibility, backed by good reputation and prior work. Otherwise you'd have to accept that people can easily soar up in the air based on what you see at a David Copperfield show. If NASA builds such a device and it does what you described above (as confirmed by other experts and space agencies), that would be "extraordinary evidence".
Dr.White filming their test stand in operation....
Granted, the short film was posted without approval/authorization (hence why it is so hard to find) but it is clear that "something" makes their setup move.(8.3 revolutions per hour, iirc)
What remains to do is to identify WHAT makes it move...
It might be vibrations, it might Lorentz forces, it might be thermal (less likely as they tried hard to eliminate that part in vacuum), or... it might be that there is indeed an EM effect that we have difficult to understand how it's working....
It is not something that hides in statistical data and can be endlessly debated on it validity. It turns, no question about that...
It now needs replication and it needs validation by elimination of all "other possible causes".
And that's exactly what Michelle, Jamie and Paul March are working on...
If only TT would provide more evidence and feedback then his name would be on top of the list too.
We all need patience, because solid testing needs a lot of preparation...hence time...specially when the budgets are limited...
Perhaps it is EM drive effect as we all hope, or it could be any number of air bearing artifacts. I do remember mention of major issues with EW's bearing. I have designed, built, and tested many air bearings and can envision self-motoring and preferred position as suspect causes. Some time ago I looked over the data from EW associated with this test and there was no obvious smoking gun (artifact-wise). However, there are questions unanswered preventing me from concluding all was valid.
Shawyer's test on the other hand was fraught with issues. Mainly, he did not rotate more than 360 degrees and the attaching cables undermined the test.
Suffice to say I could put a pile of marshmallows on different types of air bearings and make them rotate via different techniques. My only point being that it is easy to accidentally create subtle rotation.
The thing that this pointed out to me was it is exceedingly tough to make a test and account for all the errors that can and do occur. This doesn't by any means this test was a failure one way or the other. I've been known to say several times, there is no bad data.
Shell
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#203 by PotomacNeuron on 08 Jun, 2017 03:28
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No, not just someone... someone with high credibility, backed by good reputation and prior work. Otherwise you'd have to accept that people can easily soar up in the air based on what you see at a David Copperfield show. If NASA builds such a device and it does what you described above (as confirmed by other experts and space agencies), that would be "extraordinary evidence".
Dr.White filming their test stand in operation....
Granted, the short film was posted without approval/authorization (hence why it is so hard to find) but it is clear that "something" makes their setup move.(8.3 revolutions per hour, iirc)
What remains to do is to identify WHAT makes it move...
It might be vibrations, it might Lorentz forces, it might be thermal (less likely as they tried hard to eliminate that part in vacuum), or... it might be that there is indeed an EM effect that we have difficult to understand how it's working....
It is not something that hides in statistical data and can be endlessly debated on it validity. It turns, no question about that...
It now needs replication and it needs validation by elimination of all "other possible causes".
And that's exactly what Michelle, Jamie and Paul March are working on...
If only TT would provide more evidence and feedback then his name would be on top of the list too.
We all need patience, because solid testing needs a lot of preparation...hence time...specially when the budgets are limited...
Perhaps it is EM drive effect as we all hope, or it could be any number of air bearing artifacts. I do remember mention of major issues with EW's bearing. I have designed, built, and tested many air bearings and can envision self-motoring and preferred position as suspect causes. Some time ago I looked over the data from EW associated with this test and there was no obvious smoking gun (artifact-wise). However, there are questions unanswered preventing me from concluding all was valid.
Shawyer's test on the other hand was fraught with issues. Mainly, he did not rotate more than 360 degrees and the attaching cables undermined the test.
Suffice to say I could put a pile of marshmallows on different types of air bearings and make them rotate via different techniques. My only point being that it is easy to accidentally create subtle rotation.
The thing that this pointed out to me was it is exceedingly tough to make a test and account for all the errors that can and do occur. This doesn't by any means this test was a failure one way or the other. I've been known to say several times, there is no bad data.
Shell
They made a mistake to use air bearing in the first place. Monomorphic will be able to tell you why he dropped air bearing and adopted hanging wire (torsion balance). Thetraveller said he would show us rotating EmDrive on torsion balance in September. For EmDrive of tests, where expected force is extremely small, air bearing is bad, I would say unless they had documented everything (including air bearing details, air bearing calibrations details, etc), data from such tests are bad data. -
#204 by dustinthewind on 08 Jun, 2017 04:17
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I thought I had suggested this before but in light, I am bringing it up again. The image I will attach as a method of testing the EM Drive.
"EMDrive mu-shield resonance.png"
It works by using the resonance of a pendulum to maximize the displacement for small impulses. Low damping is desirable to maximize displacement at small impulse. A one direction impulse has the effect of offsetting the swing a bit but it won't do much. This is for small displacements of a pendulum but that is all that will be needed.
The mu-metal shielding is supposed to isolate the EM drive from outside Electric/magnetic interference and keep the EM drive from attracting it self to the mu-metal container. One box can swing the other is stationary.
Sensitive equipment detects any osculation of the pendulum.
The equation I used to predict the maximum displacement of the pendulum is also attached below as, "EMDrive mu-shield resonance function.png" The symbol meanings are discussed in the green highlighted text.
The blue line is a pendulum released at an offset where the force is out of phase so the force slows it down. After some time the pendulum reverses direction and the applied force is now storing energy in the pendulum. The green line is the applied force (small force). The red osculation is the maximum amplitude the pendulum will reach. Notice the force is only in one direction, or is positive.
The maximum amplitude is given approximately in the green text as Edited:A_max = A/(2*c*w) where c is the damping constant, if I remember correct (w) is the resonant frequency, A should be a force and A/(2*c*w) = displacement = A_max or amplitude. Large forces and low damping constants and frequencies desirable, it appears, to maximize displacement.
The damping constant (c) can be found by c=A_force/(A_max*w), applying some known force to the pendulum at its resonant frequency and observing the maximum displacement, plug in values. If I am correct it can be simplified toc=1/(2*w)sorry this would be incorrect
The solution is for a sinusoidal applied force, in the form of the green line plot I believe is A/2*sin(sqrt(k/m)*t)+A/2 which came from the solution for: ode2(m*diff(y(t),t,2)+c*diff(y(t),t,1)+k*y(t)=A/2*sin(sqrt(k/m)*t)+A/2, y(t), t);.
The entire apparatus itself could be damped so as to prevent impulses from outside. Maybe sitting on rubber stoppers or something of the like.
It's been a while since I looked back at this.
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#205 by SeeShells on 08 Jun, 2017 04:29
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I'm very familiar about the issues with air bearings. We extensively used air bearings in our equipment we designed for the semiconductor industry.No, not just someone... someone with high credibility, backed by good reputation and prior work. Otherwise you'd have to accept that people can easily soar up in the air based on what you see at a David Copperfield show. If NASA builds such a device and it does what you described above (as confirmed by other experts and space agencies), that would be "extraordinary evidence".
Dr.White filming their test stand in operation....
Granted, the short film was posted without approval/authorization (hence why it is so hard to find) but it is clear that "something" makes their setup move.(8.3 revolutions per hour, iirc)
What remains to do is to identify WHAT makes it move...
It might be vibrations, it might Lorentz forces, it might be thermal (less likely as they tried hard to eliminate that part in vacuum), or... it might be that there is indeed an EM effect that we have difficult to understand how it's working....
It is not something that hides in statistical data and can be endlessly debated on it validity. It turns, no question about that...
It now needs replication and it needs validation by elimination of all "other possible causes".
And that's exactly what Michelle, Jamie and Paul March are working on...
If only TT would provide more evidence and feedback then his name would be on top of the list too.
We all need patience, because solid testing needs a lot of preparation...hence time...specially when the budgets are limited...
Perhaps it is EM drive effect as we all hope, or it could be any number of air bearing artifacts. I do remember mention of major issues with EW's bearing. I have designed, built, and tested many air bearings and can envision self-motoring and preferred position as suspect causes. Some time ago I looked over the data from EW associated with this test and there was no obvious smoking gun (artifact-wise). However, there are questions unanswered preventing me from concluding all was valid.
Shawyer's test on the other hand was fraught with issues. Mainly, he did not rotate more than 360 degrees and the attaching cables undermined the test.
Suffice to say I could put a pile of marshmallows on different types of air bearings and make them rotate via different techniques. My only point being that it is easy to accidentally create subtle rotation.
The thing that this pointed out to me was it is exceedingly tough to make a test and account for all the errors that can and do occur. This doesn't by any means this test was a failure one way or the other. I've been known to say several times, there is no bad data.
Shell
They made a mistake to use air bearing in the first place. Monomorphic will be able to tell you why he dropped air bearing and adopted hanging wire (torsion balance). Thetraveller said he would show us rotating EmDrive on torsion balance in September. For EmDrive of tests, where expected force is extremely small, air bearing is bad, I would say unless they had documented everything (including air bearing details, air bearing calibrations details, etc), data from such tests are bad data.
All of the DYIers went with the Torsion Wire Pendulum with the guidance of Dr. Rodal and others here.
The data wasn't bad if you consider all of the data including the test bed and fixtures. The data allowed questions to be raised on the validly of the airbearing setup which I agree with. Personally I would have never went with a spherical airbearing.
Shell -
#206 by R.W. Keyes on 08 Jun, 2017 08:00
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I have an advanced 3D printer: Stratasys Fortus 360mc, upgraded to 400mc specs, build volume 40.6 x 35.5 x 40.6 cm (14" x 16" x 14") and can use a wide variety of plastics. I will be shortly moving much of my work from PLA and ABS and into the Nylon and the very high-performance Ultem. I would very much enjoy talking about applications of 3D printing to EMdrive. The noise level in this forum is pretty high and it is going to take me a little while but I will have something of substance to post within the next day or two.
...
I'm about to have access to a 3D printer that has a 12" (40cm) square build area and can print higher temp materials like PETG and Nylon. Also for copper plating I've used a company in Baltimore, MD called Repliform (http://www.repliforminc.com/) who did an amazing job for us on a spherical object.
These are all very good points. Thank you. The way I see it, this can go several ways. The most obvious route is to 3D print the parts and simply cover them with EMI shielding copper conductive adhesive tape. Alternatively, one could 3D print, sand, and then copper plate. Yet another option is to 3D print and then use a process like the Virtual Foundry (http://www.thevirtualfoundry.com/) to make solid copper parts. The last option, and the best route in my opinion, is to 3D print wax copies of the end plates and then use the lost wax process to create parts which are then machined to exact specifications.
Usually what you do with these kinds of requirements is 3D print a 'near net shape' (adding extra material) and then machine it down - 'file to fit'
As this is circular, you should be able to put it on a lathe and get a really good finish. Polishing most plastics can be done with a heat gun 
Oh, and check out this video which was uploaded this morning on 3D printing! (lightly related) -
#207 by WarpTech on 09 Jun, 2017 02:49
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I don't think it is so much they censor confirming data as there is none. I specifically asked you to point me to the experiments and you did not.Regarding your example of quantum mechanics, there is a growing body of evidence that Hydrogen exists in lower or fractional states according to multiple new experiments. QM doesn't admit such fractional states. Accordingly, if you ask any physicist they will tell you such states cannot exist because they are not admitted in QM and we know QM is 'true'. They say millions of experiments have been conducted consistent with QM for over a century. It's completely proven. So what do the proponents need to do to show that hydrogen does exist in lower 'fractional' states? How much data does it take? Does it matter who does the confirming experiment? In practice, what would you consider the necessary 'extraordinary' evidence? Thanks.
I cannot answer your question because I don't know what you mean by a fractional state of hydrogen. A quick google search turned up nothing. If you point me to these experiments, I could give a better answer, but for now it could be anything from experiments showing a new state that is consistent with the rest of quantum, but had either been overlooked in the theory due to complicated preconditions necessary for it to exist, or simply not formed experimentally until now. On the other hand it could be talking about electron orbitals that don't fit Schrodinger's equation, and they will need a lot of careful data showing there is not some contaminant in their experiment, and explaining why no one has ever noticed the extra line in the emission spectrum of hydrogen.
Fractional states are those with principle quantum numbers as fractions such as 1/2, 1/3, 1/4, and so on where the electron is closer and more tightly bound. These states are stable and non radiative and below the accepted ground state and thus release huge amounts of energy as they form. The scientist is Randell Mills at Brilliant Light Power. Mills calls these 'hydrino' or small hydrogen states. A word of caution, the Wikipedia editors consider it junk science and they actively censor any confirming data concentrating mainly on snarky public comments from well known scientists opposed to the idea. Mills holds the worlds record for pissing off the most Nobel laureates. But at least they've heard of him.
"incompatible with key equations of Quantum Mechanics" is not a snarky comment, it is a problem that would have to be addressed. So far you have pointed me to one collection of claims that contradict a whole lot of known physics, and 0 supporting evidence. These claims would need either a huge amount of data or a few very significant experiments (scientific definition of significance). He has had tons of funding and plenty of time, and if any of his claims worked, he should have created irrefutable demonstrations by now.
I do not think the quantum number, n=1/2, 1/3, etc. is realistic, but I wouldn't say "0 supporting evidence" for a reduced ground state energy. If an observer measures the spectrum of a hydrogen atom in the local, at-rest, inertial reference frame, and compares it to a hydrogen atom that is inside a gravity well. It appears that the hydrogen atom's spectrum is red-shifted by the gravity well. When the atom transitions to the ground state, the atom in the gravity well will have a lower energy than the atom that is not in the gravity well.
So if he wants to observe this affect, he would need to create (or simulate) a gravity well in the Lab. One way to simulate it would be to give the atoms very high velocity and SR effects will lower the ground state energy. It's all a matter of clock rates (frequency is energy).
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#208 by Rodal on 09 Jun, 2017 03:33
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Back from NIAC's orientation Meeting at NASA's headquarters . There are many exciting NIAC projects this year: https://www.nasa.gov/press-release/nasa-invests-in-22-visionary-exploration-concepts
Here is a picture at the National Air and Space Museum, Smithsonian Institution, standing next to one of the Saturn V F-1 gas-generator cycle rocket engine nozzles, where I am next to Prof. Heidi Fearn (California State University, Fullerton) and Marshall Eubanks (MIT educated physicist, ex Jet Propulsion Laboratory, and astronomer at the U.S. Naval Observatory.)
During the Evening Social I was lucky to be seated between and listen to and learn from Dr. John G. Cramer, and Dr. Michael I. Yarymovych.
Dr. John G. Cramer, Professsor of Physics at the University of Washington, who also works with the STAR (Solenoidal Tracker At RHIC) detector at the new Relativistic Heavy Ion Collider (RHIC) at Brookhaven National Laboratory, and the particle accelerator at CERN in Geneva, Switzerland. Among his many publications is the book "The Quantum Handshake: Entanglement, Nonlocality and Transactions" Springer; 1st ed. 2016 edition. His published novels consist of Twistor (1989) and Einstein's Bridge (1997); both within the hard science fiction genre.
Dr. Michael I. Yarymovych, was Boeing V.P. for international technology of the Information, Space and Defense Systems Group. V.P. for Rockwell International, in advanced development, missile defense, engineering of the Space Shuttle, Global Positioning System. Assistant Administrator of the U. S. Energy Research and Development Administration, Chief Scientist of the U.S. Air Force, Director of NATO AGARD in Paris, France, Deputy Assistant Secretary of the USAF for R&D and Technical Director of the USAF Manned Orbital Laboratory. Previously at NASA Headquarters Manned Space Flight Program involved with the Apollo lunar landing effort and initial definition studies of the Space Station and the Space Shuttle. Ex Chairman of AGARD and its successor the NATO Research and Technology Organization. 2002 recipient of the NATO RTO's highest award, the von Karman Medal.
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#209 by bad_astra on 09 Jun, 2017 14:38
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I see Heidi Fearn has a Mach Effect test proposal on the list.
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#210 by OnlyMe on 09 Jun, 2017 15:57
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.....
.... If an observer measures the spectrum of a hydrogen atom in the local, at-rest, inertial reference frame, and compares it to a hydrogen atom that is inside a gravity well. It appears that the hydrogen atom's spectrum is red-shifted by the gravity well. When the atom transitions to the ground state, the atom in the gravity well will have a lower energy than the atom that is not in the gravity well.
....
I seems what you are suggesting is that the red-shift is due to the affect of a gravity well on an atom's ground state, rather than the affect of the gravity well on the propagation of the associated red-shifted photons, as they travel out of the gravity well.
It is entirely possible that the ground state of an atom is affected by its location within a gravity well, that would be my assertion (for different reasons beyond this discussion).., but I am unconvinced, that. on its own, this explains any observed red-shift in its emission spectrum. -
#211 by Bob012345 on 09 Jun, 2017 18:07
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I don't think it is so much they censor confirming data as there is none. I specifically asked you to point me to the experiments and you did not.Regarding your example of quantum mechanics, there is a growing body of evidence that Hydrogen exists in lower or fractional states according to multiple new experiments. QM doesn't admit such fractional states. Accordingly, if you ask any physicist they will tell you such states cannot exist because they are not admitted in QM and we know QM is 'true'. They say millions of experiments have been conducted consistent with QM for over a century. It's completely proven. So what do the proponents need to do to show that hydrogen does exist in lower 'fractional' states? How much data does it take? Does it matter who does the confirming experiment? In practice, what would you consider the necessary 'extraordinary' evidence? Thanks.
I cannot answer your question because I don't know what you mean by a fractional state of hydrogen. A quick google search turned up nothing. If you point me to these experiments, I could give a better answer, but for now it could be anything from experiments showing a new state that is consistent with the rest of quantum, but had either been overlooked in the theory due to complicated preconditions necessary for it to exist, or simply not formed experimentally until now. On the other hand it could be talking about electron orbitals that don't fit Schrodinger's equation, and they will need a lot of careful data showing there is not some contaminant in their experiment, and explaining why no one has ever noticed the extra line in the emission spectrum of hydrogen.
Fractional states are those with principle quantum numbers as fractions such as 1/2, 1/3, 1/4, and so on where the electron is closer and more tightly bound. These states are stable and non radiative and below the accepted ground state and thus release huge amounts of energy as they form. The scientist is Randell Mills at Brilliant Light Power. Mills calls these 'hydrino' or small hydrogen states. A word of caution, the Wikipedia editors consider it junk science and they actively censor any confirming data concentrating mainly on snarky public comments from well known scientists opposed to the idea. Mills holds the worlds record for pissing off the most Nobel laureates. But at least they've heard of him.
"incompatible with key equations of Quantum Mechanics" is not a snarky comment, it is a problem that would have to be addressed. So far you have pointed me to one collection of claims that contradict a whole lot of known physics, and 0 supporting evidence. These claims would need either a huge amount of data or a few very significant experiments (scientific definition of significance). He has had tons of funding and plenty of time, and if any of his claims worked, he should have created irrefutable demonstrations by now.
I do not think the quantum number, n=1/2, 1/3, etc. is realistic, but I wouldn't say "0 supporting evidence" for a reduced ground state energy. If an observer measures the spectrum of a hydrogen atom in the local, at-rest, inertial reference frame, and compares it to a hydrogen atom that is inside a gravity well. It appears that the hydrogen atom's spectrum is red-shifted by the gravity well. When the atom transitions to the ground state, the atom in the gravity well will have a lower energy than the atom that is not in the gravity well.
So if he wants to observe this affect, he would need to create (or simulate) a gravity well in the Lab. One way to simulate it would be to give the atoms very high velocity and SR effects will lower the ground state energy. It's all a matter of clock rates (frequency is energy).
It has nothing to do with gravity. It's an interaction of a hydrogen atom with an appropriate catalyst. I attached a photo of the extreme UV spectra that shows the formation of the hydrino state. The double peak is a clear signature of the two stage process of hydrino formation. Here is a test run from last year, it's not a small effect as these tests kept vaporizing the tungstun electrodes so they went to liquid silver electrodes in the latest design.
Needless to say, such a reaction hold great promise as a power source for any EMDrive or MEGA based vehicle for liftoff and local solar system operations when solar power isn't enough.
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#212 by otlski on 09 Jun, 2017 22:27
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They made a mistake to use air bearing in the first place. Monomorphic will be able to tell you why he dropped air bearing and adopted hanging wire (torsion balance). Thetraveller said he would show us rotating EmDrive on torsion balance in September. For EmDrive of tests, where expected force is extremely small, air bearing is bad, I would say unless they had documented everything (including air bearing details, air bearing calibrations details, etc), data from such tests are bad data.
No offense meant toward Jamie but there is a huge difference between a proper air bearing as opposed to a DIY effort. A proper air bearing is highly linear, very stiff (in the air gap), very low perturbation torque, and designed so that its meager but highly efficient air flow does not impinge on the rotor (much). As for EW, I'd like to know the manufacturer of said air bearing and why/how it was so troublesome. For me as an instrument designer and being experienced with these bearings, they would be my starting point. Fully characterizing one would take about a day and if it is a good bearing from a reputable supplier, would be behave consistently over the long term. I have not run the numbers but I am guessing an air bearing would have two orders of magnitude better sensitivity than is needed for the supposed thrust turned torque levels an EM drive is said to generate. The air bearing would be my starting point for the freely rotating apparatus as what EW attempted, and for a constrained direct force measuring device. Where air bearings fall down is in the vacuum environment we all would like to see as the next step (after positive results in air are strongly indicated). Even at that, some of our competitors have vacuum scavenged bearings that likely would help the situation. -
#213 by Monomorphic on 09 Jun, 2017 23:55
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At the time, I thought it was worth noting that EW's Cavendish Balance Rotational experiment continued to rotate after RF was turned off. My understanding is the air bearing used has a known problem of residual swirl torque. Perhaps some kind of magnetic bearing would be best.
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#214 by RERT on 10 Jun, 2017 13:26
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Surely that's as expected, angular momentum being what it is. The graph seems compelling to me, if it shows what I think it does: no rotation prior to RF on (no air bearing effect) , angular acceleration during RF on, and coasting at a fixed rate of rotation after RF off.
Is there a detail I'm missing which causes scepticism? -
#215 by otlski on 10 Jun, 2017 13:31
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At the time, I thought it was worth noting that EW's Cavendish Balance Rotational experiment continued to rotate after RF was turned off. My understanding is the air bearing used has a known problem of residual swirl torque. Perhaps some kind of magnetic bearing would be best.
Yes, pretty close to my thoughts. Strictly speaking, it is not the fact that it continued to rotate at nearly the same rate. You would expect this to happen to a large degree because the overall friction is so low and there is an appreciable MOI about the rotation axis. Given the unknown timing resolution and the relatively short period after turn off, I would expect to see something close to the graph you reposted above. However, and this is important, there should be a negative acceleration not a positive acceleration after turn off. Granted because of the underlined from above, the negative acceleration may go undetected but we absolutely should not see a positive acceleration.
How much negative acceleration should there be? Well both the air bearing itself and the experimental payload exhibit a torque decay comprised of three terms.
Coulomb friction - fixed amount related to "break-away" shearing air molecules apart from each other
Viscous friction - fluid in motion, rises linearly with rotation rate
Turbulence friction - rise as the square of the rotation rate
Considering a well behaved air bearing, in most cases the payload's contribution to torque decay will dominate. Specifically, for EW's experiment the viscous friction would be the major contributor. This is another way of saying nothing much is available to slow the experiment's rotation rate after turn off except for air drag. Given a long enough coast duration we should see this. It should not accelerate as EW's appears to do.
Separate thought. Just to clarify for the readers. What EW calls swirl I am calling motoring. Same phenomena different nomenclature.
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#216 by otlski on 10 Jun, 2017 13:34
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Surely that's as expected, angular momentum being what it is. The graph seems compelling to me, if it shows what I think it does: no rotation prior to RF on (no air bearing effect) , angular acceleration during RF on, and coasting at a fixed rate of rotation after RF off.
Is there a detail I'm missing which causes scepticism?
Agreed. The turn on point and the beginning of rotation is very interesting. What happens at turn off is questionable, -
#217 by aero on 10 Jun, 2017 16:18
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Surely that's as expected, angular momentum being what it is. The graph seems compelling to me, if it shows what I think it does: no rotation prior to RF on (no air bearing effect) , angular acceleration during RF on, and coasting at a fixed rate of rotation after RF off.
Is there a detail I'm missing which causes scepticism?
Agreed. The turn on point and the beginning of rotation is very interesting. What happens at turn off is questionable,
Well, something happened, that is clear. Looks to me like nothing at all for 15 minutes after RF turn-on. Why? Then it looks like the RF started something that continued after RF turn-off, especially visible the first minutes after turn-off but continuing for hours. 'Course I could be reading the graph wrong. Do we know the MOI of the set-up?
Do I recall correctly that we have seen the characteristic of Force tailing off much more slowly than expected in other experiments? I suppose if the device really is related to the Mach effect then maybe time is required to experience the reaction of the more distant universe... -
#218 by RotoSequence on 10 Jun, 2017 16:27
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Surely that's as expected, angular momentum being what it is. The graph seems compelling to me, if it shows what I think it does: no rotation prior to RF on (no air bearing effect) , angular acceleration during RF on, and coasting at a fixed rate of rotation after RF off.
Is there a detail I'm missing which causes scepticism?
Agreed. The turn on point and the beginning of rotation is very interesting. What happens at turn off is questionable,
Every EM Drive experiment has had anomalies once the RF power is removed, without a sharp cutoff. It's the reason why I'm intrigued by the degraded space-time hypothesis. -
#219 by X_RaY on 10 Jun, 2017 19:11
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At the time, I thought it was worth noting that EW's Cavendish Balance Rotational experiment continued to rotate after RF was turned off. My understanding is the air bearing used has a known problem of residual swirl torque. Perhaps some kind of magnetic bearing would be best.
Sounds like a possible error source regarding the further slight accelleration after RF-power was turned off. I think some kind of thermal effect could play into also.
A magnatic bearing sounds good but it would interact with static and slow variable external fields, therefore I am not sure that this would the best way.
As this is circular, you should be able to put it on a lathe and get a really good finish. Polishing most plastics can be done with a heat gun 