Quote from: TheTraveller on 07/07/2015 12:29 pmQuote from: Rodal on 07/07/2015 12:24 pmQuote from: TheTraveller on 07/07/2015 12:18 pmRoger Shawyer's IAC 2014 paper has been peer reviewed and accepted for publication in Acta Astronautica, the IAF journal.So , is the "2015 peer reviewed paper" that was going to "end all doubt" the same IAC 2014 paper he presented at the 2014 conference? Or is there something new in the Acta Astronautica version that was not present in the 2014 presentation?What is in the document has been peer reviewed.If you have any doubts about the validity of the comments in the paper, take it up with Acta Astronautica and their peer reviewers.Have attached a few comments from the paper. Comments that are now peer reviewed.What prompted your aggressive Non-Sequitur "If you have any doubts about the validity of the comments in the paper, take it up with Acta Astronautica and their peer reviewers." ? there was nothing in my question about doubts about validity of anything. I just asked about whether there was something new in the peer-reviewed paper as you had previously written that the 2015 peer-reviewed paper was going "to remove all doubt"This is a statement ("to remove all doubt") you made, not that Shawyer made or anything to do with Acta Astronautica. I simply don't understand how can a paper already presented in 2014 is going to "remove all doubt" when re-published in 2015, so I was asking whether there was something new in the re-publication that was going to remove all doubts in 2015 that were still lingering from the 2014 presentation. If it was going to remove all doubt it should have removed it in 2014 when originally presented, not when re-published in 2015, practically a year later.
Quote from: Rodal on 07/07/2015 12:24 pmQuote from: TheTraveller on 07/07/2015 12:18 pmRoger Shawyer's IAC 2014 paper has been peer reviewed and accepted for publication in Acta Astronautica, the IAF journal.So , is the "2015 peer reviewed paper" that was going to "end all doubt" the same IAC 2014 paper he presented at the 2014 conference? Or is there something new in the Acta Astronautica version that was not present in the 2014 presentation?What is in the document has been peer reviewed.If you have any doubts about the validity of the comments in the paper, take it up with Acta Astronautica and their peer reviewers.Have attached a few comments from the paper. Comments that are now peer reviewed.
Quote from: TheTraveller on 07/07/2015 12:18 pmRoger Shawyer's IAC 2014 paper has been peer reviewed and accepted for publication in Acta Astronautica, the IAF journal.So , is the "2015 peer reviewed paper" that was going to "end all doubt" the same IAC 2014 paper he presented at the 2014 conference? Or is there something new in the Acta Astronautica version that was not present in the 2014 presentation?
Roger Shawyer's IAC 2014 paper has been peer reviewed and accepted for publication in Acta Astronautica, the IAF journal.
Quote from: rfmwguy on 07/07/2015 03:35 amSo, trying to grasp all theories here lead me to plasmons then to landau damping: https://en.m.wikipedia.org/wiki/Landau_damping and langmuir waves: https://en.m.wikipedia.org/wiki/Plasma_oscillation. https://en.m.wikipedia.org/wiki/File:Phys_interp_landau_damp.svg"It is possible to imagine Langmuir waves as waves in the sea, and the particles as surfers trying to catch the wave, all moving in the same direction. If the surfer is moving on the water surface at a velocity slightly less than the waves he will eventually be caught and pushed along the wave (gaining energy), while a surfer moving slightly faster than a wave will be pushing on the wave as he moves uphill (losing energy to the wave)."Gaining energy can be viewed as gaining vector velocity I believe. What struck me is previous assertions about an emdrive needing an inertial "nudge" from a "motionless" reference frame. Math wizards and maybe naysayers might want to look at the formulas to see if there is any correlation that can be made...we're talking particle and wave interactions yielding acceleration...not exactly my major in college Well here is a primer from recommended reading from Doc Rodal himself, the man is trying his darndest to burn my gray matter up. Even if you read the very well written text and ignore the pigeon scratchings it can help a lot. I've read it once and will be refreshing by reading again.Shell
So, trying to grasp all theories here lead me to plasmons then to landau damping: https://en.m.wikipedia.org/wiki/Landau_damping and langmuir waves: https://en.m.wikipedia.org/wiki/Plasma_oscillation. https://en.m.wikipedia.org/wiki/File:Phys_interp_landau_damp.svg"It is possible to imagine Langmuir waves as waves in the sea, and the particles as surfers trying to catch the wave, all moving in the same direction. If the surfer is moving on the water surface at a velocity slightly less than the waves he will eventually be caught and pushed along the wave (gaining energy), while a surfer moving slightly faster than a wave will be pushing on the wave as he moves uphill (losing energy to the wave)."Gaining energy can be viewed as gaining vector velocity I believe. What struck me is previous assertions about an emdrive needing an inertial "nudge" from a "motionless" reference frame. Math wizards and maybe naysayers might want to look at the formulas to see if there is any correlation that can be made...we're talking particle and wave interactions yielding acceleration...not exactly my major in college
...@shellSmall world, SLAC used to be a customer of mine back in the day for passives. This is particle and wave interaction at its finest...Megavolt...whoa. At first glance, it seems like an ion engine on steroids. Perhaps not applicable to our testing, but does show the energy possible using EM and particle interactions. Still stuck in theory about this. An rf source produces the wave action, where do the particles come from if indeed we are seeing force presented because of the interaction?I do have some concern about poynting vectors yielding motion. While PV is directional pressure (potential outside a physical conductor), seems to me that the pressure is useless unless its applied against something. Some could argue the force is applied against the irradiator itself...I'm just too lame to visualize the concept at the moment...and I must visualize before putting pen to paper. A total net pointing vector of a system seems to yield a balance or zero force due to CoE.Unless...we don't grasp all of the properties of a free space medium, which I think is a given.
It can not hurt to have different opinions, certainly not at this stage, where we, external observers, are still looking for confirmation that there is indeed a force developing inside the EMdrive.At best there is "some indication", but far from conclusive. I can imagine R.Shawyer having a different point of view, because he's been spending many years on the topic.One of the key elements to assess which of the theories fits best, will be the experimental setups that investigate the possible contribution of the side walls. If they contribute nothing, then Shawyer is more likely to have the right direction, if they contribute something (or everything) then Shawyer will have to reconsider part of his theory, i think.Although the paper contains some new elements, I would rather have preferred some hardcore data on the 2nd generation engine, instead of linear projections of what might/could be possible based upon mathematical models that have yet to be confirmed by experiments.I, fe, have a hard time believing that the Q will scale so linear as has been assumed, but I would gladly be proven wrong by an experiment that shows it can be done....Starting to get worried about the NASA highpower test. If only P.Marchal was allowed to drop a few lines on the progress made there...
Quote from: rfmwguy on 07/07/2015 01:57 pm...@shellSmall world, SLAC used to be a customer of mine back in the day for passives. This is particle and wave interaction at its finest...Megavolt...whoa. At first glance, it seems like an ion engine on steroids. Perhaps not applicable to our testing, but does show the energy possible using EM and particle interactions. Still stuck in theory about this. An rf source produces the wave action, where do the particles come from if indeed we are seeing force presented because of the interaction?I do have some concern about poynting vectors yielding motion. While PV is directional pressure (potential outside a physical conductor), seems to me that the pressure is useless unless its applied against something. Some could argue the force is applied against the irradiator itself...I'm just too lame to visualize the concept at the moment...and I must visualize before putting pen to paper. A total net pointing vector of a system seems to yield a balance or zero force due to CoE.Unless...we don't grasp all of the properties of a free space medium, which I think is a given.You can choose to look at a half-filled cup as being half empty or half full.You can choose to state that a Poynting vector is useless unless it is applied against something, it will be dissipated as heat. This I already stated repeatedly (that the Poynting vector can get dissipated into heat).But you might also choose to view this as the fact that having something to push or pull against will be of no use unless pushing or pulling is being done. And what we have shown again, is that:* There is a net, non-zero Poynting vector over an integer number of periods. This negates what Greg Egan showed, where he concluded that the Poynting vector is zero for an EM Drive. * The Poynting vector is increasing with time. This is required in more general situations (for radiation pressure all that is required is a non-zero average). This is very significant. It remains to be explored whether it is just a transient.It is like you saying: I see a ship and you have shown somebody is rowing, but I don't know whether there is some medium to row against.Somebody else may see this as follows: oh this is significant, as even if the ship was on water, if there was no rowing, it would not be able to move.You might say, well I am not satisfied because you still have not shown what makes the ship move. To which I answer: Rome wasn't built in a day. Certainly Rome wasn't built without laying the foundation and people working on it saying "Rome cannot be built" and remaining in the forest.
Quote from: Rodal on 07/07/2015 03:09 amQuote from: WarpTech on 07/07/2015 02:55 am...In the first paragraph of section 4 of this paper, they decompose the wave vector into time-like and space-like, orthogonal components. This is a more precise derivation of exactly what I am doing. The space-like component must shift mass to match the boundary conditions as the time-like component travels down the waveguide. It seems you "believe" waveguides are linear and cannot deviate from this expectation. In the case of a tapered waveguide, it mimics gravity which is non-linear. So, I still do not see what is "wrong" with my equation. Although, now I do see a better way to derive it and reference it. Thank you!ToddTodd,Thank you for pointing this out, as I had not read this paper. You are right:http://arxiv.org/abs/0708.3519Photons inside a waveguide as massive particlesZhi-Yong Wang1, Cai-Dong XiongSection 4 RELATIVISTIC QUANTUM-MECHANICAL EQUATION OF GUIDED PHOTONSQuote Eqs. (20) and (21) are expressed in the arbitrary coordinate system (associated with a frame wherefrom the waveguide is viewed along an arbitrary 3D spatial direction), they can be simplified in the coordinate system (associated with a frame wherefrom the waveguide is viewed along the x123{,,}aaa123{,,}eee3-axis, and then one has L3(,0,0,)xtxμ=and 12(0,,,0)mkkμη=). This similar to what Dr. Notsosureofit was discussing from a long time ago, and I had a hard time grasping I also tried to point out many a post ago in (I think) the last EM drive thread, that a standing wave might be interpretable as an 'exotic' type of dynamically created massive particle. This whole tapered frustum actually looks to me as if this geometry squeezed one side of this dynamically created exotic particle equivalent. Assuming this point of view, this squeezed dynamic particle should then react and try to escape the squeezing towards the wider end of the frustum, hence being sort of accelerated, while the equivalent but opposite impulse is being imparted towards the smaller frustum end. If this were the case, the type of squeezing reaction might even depend on the type of exotic particle equivalent that is being dynamically generated in terms of frequency, energy density and field distribution/modes. Just the same as static types of particles have different properties that particle physics knows.
Quote from: WarpTech on 07/07/2015 02:55 am...In the first paragraph of section 4 of this paper, they decompose the wave vector into time-like and space-like, orthogonal components. This is a more precise derivation of exactly what I am doing. The space-like component must shift mass to match the boundary conditions as the time-like component travels down the waveguide. It seems you "believe" waveguides are linear and cannot deviate from this expectation. In the case of a tapered waveguide, it mimics gravity which is non-linear. So, I still do not see what is "wrong" with my equation. Although, now I do see a better way to derive it and reference it. Thank you!ToddTodd,Thank you for pointing this out, as I had not read this paper. You are right:http://arxiv.org/abs/0708.3519Photons inside a waveguide as massive particlesZhi-Yong Wang1, Cai-Dong XiongSection 4 RELATIVISTIC QUANTUM-MECHANICAL EQUATION OF GUIDED PHOTONSQuote Eqs. (20) and (21) are expressed in the arbitrary coordinate system (associated with a frame wherefrom the waveguide is viewed along an arbitrary 3D spatial direction), they can be simplified in the coordinate system (associated with a frame wherefrom the waveguide is viewed along the x123{,,}aaa123{,,}eee3-axis, and then one has L3(,0,0,)xtxμ=and 12(0,,,0)mkkμη=). This similar to what Dr. Notsosureofit was discussing from a long time ago, and I had a hard time grasping
...In the first paragraph of section 4 of this paper, they decompose the wave vector into time-like and space-like, orthogonal components. This is a more precise derivation of exactly what I am doing. The space-like component must shift mass to match the boundary conditions as the time-like component travels down the waveguide. It seems you "believe" waveguides are linear and cannot deviate from this expectation. In the case of a tapered waveguide, it mimics gravity which is non-linear. So, I still do not see what is "wrong" with my equation. Although, now I do see a better way to derive it and reference it. Thank you!Todd
Eqs. (20) and (21) are expressed in the arbitrary coordinate system (associated with a frame wherefrom the waveguide is viewed along an arbitrary 3D spatial direction), they can be simplified in the coordinate system (associated with a frame wherefrom the waveguide is viewed along the x123{,,}aaa123{,,}eee3-axis, and then one has L3(,0,0,)xtxμ=and 12(0,,,0)mkkμη=).
Quote from: rfmwguy on 07/07/2015 01:57 pm...@shellSmall world, SLAC used to be a customer of mine back in the day for passives. This is particle and wave interaction at its finest...Megavolt...whoa. At first glance, it seems like an ion engine on steroids. Perhaps not applicable to our testing, but does show the energy possible using EM and particle interactions. Still stuck in theory about this. An rf source produces the wave action, where do the particles come from if indeed we are seeing force presented because of the interaction?I do have some concern about poynting vectors yielding motion. While PV is directional pressure (potential outside a physical conductor), seems to me that the pressure is useless unless its applied against something. Some could argue the force is applied against the irradiator itself...I'm just too lame to visualize the concept at the moment...and I must visualize before putting pen to paper. A total net pointing vector of a system seems to yield a balance or zero force due to CoE.Unless...we don't grasp all of the properties of a free space medium, which I think is a given.You can choose to look at a half-filled cup as being half empty or half full.You can choose to state that a Poynting vector is useless unless it is applied against something, it will be dissipated as heat. This I already stated repeatedly (that the Poynting vector can get dissipated into heat).But you might also choose to view this as the fact that having something to push or pull against will be of no use unless pushing or pulling is being done. And what we have shown again, is that:* There is a net, non-zero Poynting vector over an integer number of periods. This negates what Greg Egan showed, where he concluded that the Poynting vector is zero for an EM Drive. * The Poynting vector is increasing with time. This is required in more general situations (for radiation pressure all that is required is a non-zero average). This is very significant. It remains to be explored whether it is just a transient.An imperfect analogy (a toy to think about, as all analogies are imperfect): It is like you saying: I see a ship and you have shown somebody is rowing, but I don't know whether there is some medium to row against.Somebody else may see this as follows: oh this is significant, as even if the ship was on water, if there was no rowing, it would not be able to move.You might say, well I am not satisfied because you still have not shown what makes the ship move. To which I answer: Rome wasn't built in a day. Certainly Rome wasn't built without laying the foundation and people, building it. Saying "Rome cannot be built" and remaining in the forest will not build Rome.People might say: oh, I am unsatisfied that a few people working part-time (away from their daily jobs, doing this while others watch TV) have not solved "the problem" in a few months. To which I say, it took over 360 years for Fermat's last theorem to be proven. I don't believe in prophesies stating that "people are not going to be able to show what is going on". Eventually we will know.
Once my EMDrive is working on the rotary test rig and the test data is published, full detailed plans, bill of material and suppliers lists will be made available at no cost.The build will include machined spherical end plates, highly polished, ding & scratch free internal surfaces and optional silver with gold flash coating on all internal surfaces. Unloaded cavity Q, for the coated cavity, is expected to be well over 100,000. Df is around 0.95. This will be a very efficient cavity which will include internal antenna and impedance matching system.I'm buying a lathe to machine the spherical end plates and end plate flanges, plus to make a mandrel for the 2mm thick frustum and to accurately roll/form it around the mandrel. The frustum butt join & end flanges will be silver soldered to ensure excellent electrical conductivity and strength.Design will be air tight due to an O ring between the end flanges and the end plates. The frustum side wall will have a small air valve that will allow air to be pumped out and then back filled with dry N2 at various internal pressures. This will also allow internal frustum pressure to be monitored and recorded before, during and after test runs to avoid counter claims that the Force generated was due to hot air leaks.While the build will not be that technically challenging, I MAY consider providing tested EMDrives at my material costs, to enable anyone who wishes to test an EMDrive to be able to do so without needing to build the device themselves.Same for the rotary test rig and data collection system.Please don't get me wrong, this offer will cost me considerable time and make $0 profit as I expect it will take at least 2 weeks to build, align, polish, overcoat and test each EMDrive. Device will look like the Boeing Flight Thruster and operate at 2.45GHz from a narrow band Rf generator. No magnetrons required.Once my test data is published, interested parties can contact me to discuss.
Quote from: Rodal on 07/07/2015 02:11 pmQuote from: rfmwguy on 07/07/2015 01:57 pm...@shellSmall world, SLAC used to be a customer of mine back in the day for passives. This is particle and wave interaction at its finest...Megavolt...whoa. At first glance, it seems like an ion engine on steroids. Perhaps not applicable to our testing, but does show the energy possible using EM and particle interactions. Still stuck in theory about this. An rf source produces the wave action, where do the particles come from if indeed we are seeing force presented because of the interaction?Unless...we don't grasp all of the properties of a free space medium, which I think is a given.Well said doc...u can tell I'm a natural skeptic, which is only healthy to a certain point. I do think there is rowing going on, just cannot visualize against what. That is what keeps me interested. Speaking of which, time to finish the exoskeleton.
Quote from: rfmwguy on 07/07/2015 01:57 pm...@shellSmall world, SLAC used to be a customer of mine back in the day for passives. This is particle and wave interaction at its finest...Megavolt...whoa. At first glance, it seems like an ion engine on steroids. Perhaps not applicable to our testing, but does show the energy possible using EM and particle interactions. Still stuck in theory about this. An rf source produces the wave action, where do the particles come from if indeed we are seeing force presented because of the interaction?Unless...we don't grasp all of the properties of a free space medium, which I think is a given.
...@shellSmall world, SLAC used to be a customer of mine back in the day for passives. This is particle and wave interaction at its finest...Megavolt...whoa. At first glance, it seems like an ion engine on steroids. Perhaps not applicable to our testing, but does show the energy possible using EM and particle interactions. Still stuck in theory about this. An rf source produces the wave action, where do the particles come from if indeed we are seeing force presented because of the interaction?Unless...we don't grasp all of the properties of a free space medium, which I think is a given.
Quote from: TheTraveller on 07/07/2015 05:31 amOnce my EMDrive is working on the rotary test rig and the test data is published, full detailed plans, bill of material and suppliers lists will be made available at no cost.The build will include machined spherical end plates, highly polished, ding & scratch free internal surfaces and optional silver with gold flash coating on all internal surfaces. Unloaded cavity Q, for the coated cavity, is expected to be well over 100,000. Df is around 0.95. This will be a very efficient cavity which will include internal antenna and impedance matching system.I'm buying a lathe to machine the spherical end plates and end plate flanges, plus to make a mandrel for the 2mm thick frustum and to accurately roll/form it around the mandrel. The frustum butt join & end flanges will be silver soldered to ensure excellent electrical conductivity and strength.Design will be air tight due to an O ring between the end flanges and the end plates. The frustum side wall will have a small air valve that will allow air to be pumped out and then back filled with dry N2 at various internal pressures. This will also allow internal frustum pressure to be monitored and recorded before, during and after test runs to avoid counter claims that the Force generated was due to hot air leaks.While the build will not be that technically challenging, I MAY consider providing tested EMDrives at my material costs, to enable anyone who wishes to test an EMDrive to be able to do so without needing to build the device themselves.Same for the rotary test rig and data collection system.Please don't get me wrong, this offer will cost me considerable time and make $0 profit as I expect it will take at least 2 weeks to build, align, polish, overcoat and test each EMDrive. Device will look like the Boeing Flight Thruster and operate at 2.45GHz from a narrow band Rf generator. No magnetrons required.Once my test data is published, interested parties can contact me to discuss.Traveller (hope you are feeling much better!) -Several comments if you please - first, please be most careful with the metal working lathe - they can bite bad - it is the only machine in my shop which has successfully taken a chunk out of my fingers not once but twice. - as the saying goes - shame on me. second, I am glad to hear you are using a narrow band RF source. I understand both the financial and potential technical reasons for using the ubiquitous 2.45 Ghz magnetrons, but I have a feeling that there may be some sharp frequency dependencies/interactions/"bumps in the road" around the design point which they may be masking or at least making harder to identify and quantify. I also have a feeling that the wideband nature of the signal might possible obscure the characteristics of the drive in going from an "idling" type mode to a "thrusting" type mode, or perhaps shed more light on the existance and character of such modes. Perhaps not but it would be nice to observe that cleanly.third, I would like to encourage data collection by experimenters "off design" i.e. at frequencies seperated from the design point of the frustum, as well as modulated by various schemes. I am NOT necessarily suggesting moving outside the "microwave" regions, but characterization of the DUT (device under test) in "off design" situation often helps in understanding how it operates at design point. For instance, given a f0 design point of 2.45 Ghz. it would be most interesting to test the behavior over several orders of magnitude - say from 200 Mhz through 25 Ghz. What do I expect to see? 'Expect' is likely too strong a word but it would be interesting to see if the device exhibits any sort of tendency to pull to its design point and lock up. Or perhaps it is only metastable at the design point and requires active control to maintain efficent operation. Or are there stable "off design" points where the device will operate - perhaps less efficently. Without logical planned range testing it is difficult to know. I have seen antennas and other RF systems exhibit some very weird behavior over the years and often careful, extensive testing was required to fully understand what was happening from a theoretical stance - and in particular if the EMDRIVE is to move to a practical space drive system. I would also suggest such off design point simulations would be most interesting. I recognized that a) we may not be ready for such testing just yet as there is much to be done to show that an actual artifact that can produce thrust exists, and b) there may be easier ways to do some of it (fixed RF source and mutiple or scaleable frustums (ala Seeshell's design). But thinking about what sorts of future explorations can be done may influence the design of test units/DIY drives. Just some semi-random thoughts after the long weekend. Herman
...thrust generated in one direction and a reaction force in theopposite direction. The acceleration measured onthe SPR Demonstrator engine was in the reactionforce direction, which was opposite to the thrustinitially measured on the static composite balancetest rig. Subsequent tests at SPR showed that boththrust and reaction force could be measured on thecomposite balance rig, by selection of differentspring constants.
...To compensate for the decrease infrequency due to the Doppler shift underacceleration, the axial length of the cavityincreased by piezoelectric elements, mountedbetween the side wall and the small end plate. Thevoltage controlling the length of the piezoelectricelement is determined by a processor, fed by theoutput of an accelerometer.
* There is a net, non-zero Poynting vector over an integer number of periods. This negates what Greg Egan showed, where he concluded that the Poynting vector is zero for an EM Drive.
* The Poynting vector is increasing with time. This is required in more general situations (for radiation pressure all that is required is a non-zero average). This is very significant. It remains to be explored whether it is just a transient.
Trying to grasp the conjecture about vibration or ratcheting of the EM Drive and how best to ask Tajmar about it, and what should experimenters like RFMWGUY and Shell and DrBagelBytes do about it.As I understand TheTraveller, he has decided the (only ?) satisfactory way to measure the elusive "EMDrive thrust" is to conduct an experiment on a rotating device mounted on a bearing. 1) As I understand it, that means that he finds it unsatisfactory to measure the elusive "EMDrive thrust" not just using mechanical scales but also the teeter-totter and laser pointer that RFMWGUY and SeeShells and DrBagelBytes are planning to use. Is that correct?2) If that is so, what is the best thing that RFMWGUY or SeeShells or DrBagelBytes (or Tajmar or NASA) can do to "motivate" the EM Drive with their set-up? Is it just to tap it? Or vibrating it, if so how, with what, at what frequency, amplitude and by how much?3) How are testers going to strike a balance between eliminating background forces (the motion of the teeter totter that RFMWGUY and Dr.BagelBytes have shown due to air convection) and "motivating" the EM Drive?
Some interesting stuff from:"IAC-14-C4,8.5 SECOND GENERATION EMDRIVE PROPULSION APPLIED TO SSTO LAUNCHER AND INTERSTELLAR PROBE"(Thank's Traveller)Quote...thrust generated in one direction and a reaction force in theopposite direction. The acceleration measured onthe SPR Demonstrator engine was in the reactionforce direction, which was opposite to the thrustinitially measured on the static composite balancetest rig. Subsequent tests at SPR showed that boththrust and reaction force could be measured on thecomposite balance rig, by selection of differentspring constants.Wow, measure two opposite thrusts depending on the spring-constant of your scale?!?!Sounds like "negative inertial resistance" to me.Different forces at each end (due to Vg), different consequent resonances with the setup mass, therefore different doppler-shifts excite different resonance amplitudes that determine which average thrust or reaction force gets measured.And:Quote...To compensate for the decrease infrequency due to the Doppler shift underacceleration, the axial length of the cavityincreased by piezoelectric elements, mountedbetween the side wall and the small end plate. Thevoltage controlling the length of the piezoelectricelement is determined by a processor, fed by theoutput of an accelerometer.One of Shawyer's cones had a white-gasket like material, on the large end, I thought might be PZT.Something Shawyer didn't address in the above paper is where the power goes that falls outside the cavity bandwidth. One would assume it is dissipated as heat. If an energized cavity tuning is changed, work is inserted or extracted by physically re-tuning it, the energy changing frequency accordingly.
3) How are testers going to strike a balance between eliminating background forces (the motion of the teeter totter that RFMWGUY and Dr.BagelBytes have shown due to air convection) and "motivating" the EM Drive?
Quote from: Rodal on 07/07/2015 03:33 pmTrying to grasp the conjecture about vibration or ratcheting of the EM Drive and how best to ask Tajmar about it, and what should experimenters like RFMWGUY and Shell and DrBagelBytes do about it.As I understand TheTraveller, he has decided the (only ?) satisfactory way to measure the elusive "EMDrive thrust" is to conduct an experiment on a rotating device mounted on a bearing. 1) As I understand it, that means that he finds it unsatisfactory to measure the elusive "EMDrive thrust" not just using mechanical scales but also the teeter-totter and laser pointer that RFMWGUY and SeeShells and DrBagelBytes are planning to use. Is that correct?2) If that is so, what is the best thing that RFMWGUY or SeeShells or DrBagelBytes (or Tajmar or NASA) can do to "motivate" the EM Drive with their set-up? Is it just to tap it? Or vibrating it, if so how, with what, at what frequency, amplitude and by how much?3) How are testers going to strike a balance between eliminating background forces (the motion of the teeter totter that RFMWGUY and Dr.BagelBytes have shown due to air convection) and "motivating" the EM Drive?If the EMDrive is not free to accelerate, the limited compression distance for movement a scale may offer, offers little ability to show what it can really do when it is free to accelerate without constraint.Scales will still show some Force generation but it may not be the best showing.Unless the experimenter has gone to extreme lengths to eliminate vibration, vibration will be there. Additionally the big end will experience significant sound vibratory Force shoving it gently toward to small end, which will experience less sound vibratory Forces due to reduced surface area.I believe the lack of sound vibratory forces action on the big end is why Eagleworks experienced reduce Force generation in a vacuum.
As the Chinese built, there needs to be a rejected microwave energy dump (with heat radiators), the device to the right of the microwave distribution system.
Trust you enjoyed the following comments?Especially the one showing if you build and excite the cavity properly, the spherical waves impart no Forces on the side walls as they are at right angles to the side walls. Nice effect.