Author Topic: EM Drive Developments - related to space flight applications - Thread 2  (Read 1645659 times)

Offline Star-Drive

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I know Mulletron. What I want to know is exactly how Dr White theory deals with superluminal speeds, which most physicists say leads to time-travel to the past and all the paradoxes that surface from that.


According to the video I showed from Dr Davis, superluminal speeds WITHOUT time-travel to the past are possible, if the light cone is tilted from 0 to 90 degrees only...


I think this question is related to spaceflight applications exactly because time travel IS an issue at relativistic velocities (to the future) and superluminal velocities (to the past, but not according to Dr Davis)

This question is probably more related to the spaceflight applications of a warp drive than the pure theoretical issues of how EM and Warp Drives work on quantum level, since the first is a result of spaceflight application while the second (which is being discussed in this thread) is not.

Aceshigh:

To be honest, I've not heard Dr. White talk or write about the time travel aspects of his warp-field conjecture.  I think that may be because Sonny is fairly conservative on some topics in this business, especially since his NASA management is even more super conservative in regards to anything that smacks of Sci-Fi like time travel.  Yea I know, its a tribute to Sonny's salesmanship that he has convinced his NASA/EP managers to even allow his current low cost investigations into Q-Thrusters and warp-drives based on his Q-V conjecture, when their normal response is to consider even delving into LOX/CH4 chemical rocket technology as daring...

Best,  Paul M.
Star-Drive

Offline Rodal

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http://en.wikipedia.org/wiki/Novikov_self-consistency_principle



http://www.scottaaronson.com/papers/ctc.pdf

Closed Timelike Curves Make Quantum and Classical Computing Equivalent (2009)
Scott Aaronson, MIT and  John Watrous, University of Waterloo

« Last Edit: 04/20/2015 01:12 PM by Rodal »

Offline aceshigh

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well, my guess is that CTCs are impossible and any superluminal travel (including warp drives) are impossible unless they somehow avoid travelling to the past. (I really hate the notion of timetravel to the past, although science is not based on one's preferences)

In other words, I guess the universe is probably consistent in a way that the bending of space-time geometry  is impossible if it involves time travel to the past, unless you someway engineer this bending of space-time geometry in someway similar to what I understand Dr Eric Davis talked in the video above...


@LeftField: as far as I understand, having already questioned physicists I know about it, travelling to the past if you go FTL is independent of the ship not moving inside it´s own space-time (warp drive or wormholes) does not means you WILL travel back in time, but also means nothing stops you from doing so, causing all sort of causality violations.






Offline birchoff

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well, my guess is that CTCs are impossible and any superluminal travel (including warp drives) are impossible unless they somehow avoid travelling to the past. (I really hate the notion of timetravel to the past, although science is not based on one's preferences)

In other words, I guess the universe is probably consistent in a way that the bending of space-time geometry  is impossible if it involves time travel to the past, unless you someway engineer this bending of space-time geometry in someway similar to what I understand Dr Eric Davis talked in the video above...


@LeftField: as far as I understand, having already questioned physicists I know about it, travelling to the past if you go FTL is independent of the ship not moving inside it´s own space-time (warp drive or wormholes) does not means you WILL travel back in time, but also means nothing stops you from doing so, causing all sort of causality violations.

Seems a bit premature to be worried about these issues, when we don't even have a proven and accepted theory of how the devices EagleWorks are researching will work. So from my perspective I would have to say these concerns do not matter, because at this point in the research we "don't know what we don't know". Nature could have really simple solutions for all these concerns, but in the best case we have a device that seems to show that we can manipulate the vacuum into changing the length of the path light travels. We have no clue if the effect we are seeing is actually what we think it is, until further experiments are done. So the real question for me is, other than re running the test under vacuum. What other tests can we run to further enhance our understanding of what is going on.

Offline Rodal

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Seems a bit premature to be worried about these issues, when we don't even have a proven and accepted theory of how the devices EagleWorks are researching will work. So from my perspective I would have to say these concerns do not matter, because at this point in the research we "don't know what we don't know". Nature could have really simple solutions for all these concerns, but in the best case we have a device that seems to show that we can manipulate the vacuum into changing the length of the path light travels. We have no clue if the effect we are seeing is actually what we think it is, until further experiments are done. So the real question for me is, other than re running the test under vacuum. What other tests can we run to further enhance our understanding of what is going on.
Excellent conclusion, @Birchoff.  Concerning your question "other than re running the test under vacuum. What other tests can we run to further enhance our understanding of what is going on" in reference to the interferometer path length measurements, in addition to what they are doing and planning to do, they could also consider:

 running the tests in different pure gas environments ( in addition  to the existing ambient air tests, and in addition to the planned partial vacuum tests).

(This would further put to bed the issue of whether the path length change measurement could possibly be due to refraction, of particular gases.)

EDIT: conducting the tests under certain pure inert gases may be something that they can do first, more readily, faster, than doing these interferometer path length measurements in a partial vacuum.
« Last Edit: 04/20/2015 03:22 PM by Rodal »

Offline Rodal

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QUESTION 6: Has NASA Eagleworks addressed the issue with air refraction raised in this paper by Lee and Cleaver from Baylor University?:

http://arxiv.org/ftp/arxiv/papers/1407/1407.7772.pdf

In particular, has NASA Eagleworks assessed the likelihood of the path-length-change measurements being the result of transient air heating ?

See Dr. White's preliminary assessment of that issue in the attached slide.  Ultimately though we will be running the warp-field resonant cavity with a vacuum contained in its active volume to get rid of all possibilities of air heating problems.

Best, Paul M.

Thanks Paul for your excellent answers.

Concerning the likelihood of the path-length-change measurements being the result of transient air heating, were you able to monitor the transient temperature inside the cavity with embedded thermocouples (or otherwise its external temperature with an infrared thermal camera)?

If you did monitor the transient temperature, could you make that data/plots available to the public in this forum?

Thanks
« Last Edit: 04/20/2015 03:05 PM by Rodal »

Online tchernik

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I know Mulletron. What I want to know is exactly how Dr White theory deals with superluminal speeds, which most physicists say leads to time-travel to the past and all the paradoxes that surface from that.


According to the video I showed from Dr Davis, superluminal speeds WITHOUT time-travel to the past are possible, if the light cone is tilted from 0 to 90 degrees only...


I think this question is related to spaceflight applications exactly because time travel IS an issue at relativistic velocities (to the future) and superluminal velocities (to the past, but not according to Dr Davis)

This question is probably more related to the spaceflight applications of a warp drive than the pure theoretical issues of how EM and Warp Drives work on quantum level, since the first is a result of spaceflight application while the second (which is being discussed in this thread) is not.

Don't forget that the ship is not really moving at relativistic speeds: space is.  Consequently, you could take a trip to Alpha Centauri in 2 days (or less with more power... who knows?), turn your ship around and observe the Earth as it was four years ago (as light has taken four years to get there - slow coach!). You could then observe Alpha Centauri as it is "now", and how people on the Earth will see it in four years.

With this type of technology,  it would be possible to predict when locally past events are going to be observable from the point of view of the Earth (or any other point that the light from such events had not yet reached). For example, a ship 1 light-day out from the Earth in the right place could witness a supernova before the Earth does and then be able to return to the Earth almost instantly and tell astronomers about the incoming light wave so that they could prepare to observe it.

Proviso: I am not an expert in time travel and I also have doubts about Dr Who.

This is pretty much what I take from Dr. Eric Davis presentation: not all kinds of FTL travel due to space time distortions (e.g. warp drive) result in the light cones becoming inverted. A lot of them result in just allowing the light cone of a traveler to be slightly "sideways" (e.g. any tilting less than 45 degrees avoids "instantaneous" travel or time travel), allowing the traveler to reach the classically forbidden regions very fast but without paradoxes.

In that way, you will be reaching "past" far away events from the point of view of your point of origin (being there before the light of those events reaches your point of origin), but not the past at your original light cone. As you say, if warp drives exist you could travel in a few days to Alpha Centauri, see what's going on there "in the past" from Earth's point of view (which is just due to you being traveling in a tilted light cone on a trajectory that takes you outside of the classically allowed in your light cone) and be back to report whatever you saw, but always strictly after you left.

If warp drives exist in practice, I won't be surprised if these tilted light cones can't actually bend enough to allow instantaneous or backwards time travel, but they might allow very fast, but finite travel speeds, by tilting the light cone less than 45 degrees...

But I digress: please dear Eagle Works team, continue the very valuable work of proving your points with experimental measurements, for everyone to see and replicate, and then we could emote and get excited about having impulse drives and warp drives. One step at a time.

And I also excuse myself with our kind hosts: I promise this is the last post where I'll discuss unverified claims and hypothesis.

Edit:
I re-read my comment and I think I noticed a mistake: assuming the maximum tilt of the light cone should be less than 45 degrees is wrong. Because that implies that you and your ship could be potentially moving at less than c with respect to your own warp field (inside the allowed region of the tilted light cone), when all evidence suggest you would be stationary inside of it in order to be under its influence!

Under this interpretation, a relatively stationary ship with a warp field tilting its light cone 45 degrees would be travelling exactly at c...

In general, all ships inside a warp field would follow a trajectory that is identical to that of their surrounding field, so the need of having warp fields with light cones with a tilt less than 90 degrees. So aceshigh was right.
« Last Edit: 04/20/2015 09:32 PM by tchernik »

Offline Stormbringer

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On the subject of further tests: maybe get together with some quantum communications people and devise a test of CTLs or time communications effects. Really the interferometer does this (in it's own way) anyway. But perhaps a test to deliberately check it a different way might have a different S/N ratio? Naturally the easier tests that were suggested by Dr Rodal and others could come first.
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Online dustinthewind

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I thought I would post a graphic I made of a light cone.  If I am correct for normal warp the cone just flattens suggesting that the observed mote/traveler could move some maximum distance from their original location at some later time.   

I would imagine a tilted warp cone might happen where space is swirling around a rotating black hole and drags objects around it.  If that space reaches light speed or above then the space moving away looks like an event horizon while the space moving towards us is blue-shifted in spectrum.  If the space is moving away at less than c then it should be red-shifted.  In that case if one sits still in moving space then they are moving so the axis is tilted.  (I guess if our space is expanding this suggest we might have tilted light cones?) I don't know that if the central axis is tilted beyond 45 degrees that the light cone would necessarily cross the plane.  I would think light would appear to move at 2*c, 2=m, from an outside observer in one direction and not move at all the other direction m=0 (space is moving against it and it gets nowhere).  That would suggest some distortion of our light cone but that it's not crossing the plane where the slope m = infinity. 

I would think it would require infinite energy to get to warp infinity.  Hopefully I'm not too far off here. 
« Last Edit: 04/21/2015 03:01 AM by dustinthewind »

Offline Star-Drive

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QUESTION 6: Has NASA Eagleworks addressed the issue with air refraction raised in this paper by Lee and Cleaver from Baylor University?:

http://arxiv.org/ftp/arxiv/papers/1407/1407.7772.pdf

In particular, has NASA Eagleworks assessed the likelihood of the path-length-change measurements being the result of transient air heating ?

See Dr. White's preliminary assessment of that issue in the attached slide.  Ultimately though we will be running the warp-field resonant cavity with a vacuum contained in its active volume to get rid of all possibilities of air heating problems.

Best, Paul M.

Thanks Paul for your excellent answers.

Concerning the likelihood of the path-length-change measurements being the result of transient air heating, were you able to monitor the transient temperature inside the cavity with embedded thermocouples (or otherwise its external temperature with an infrared thermal camera)?

If you did monitor the transient temperature, could you make that data/plots available to the public in this forum?

Thanks

Dr. Rodal:

I'm attaching three slides that provide a bit more insight into the data sets that were taken over two weekends in the Warp-field interferometer tests.  In the last you will note the temp rise of the resonant cavity over its first 70 minutes of on/off cycling.  After determining this thermal rise time constant with our IR camera, we let the test article warm up for approximately one hour before starting our data acquisition of 27,000 to 30,000 ~1.5 second on/off cycles with each on/off cycle resulting in a CCD camera picture with a few examples shown in the attached FFTs of Imager slide.  I've also appended a slide with the FFT noise present at the 2/3 second time point.

"If you did monitor the transient temperature, could you make that data/plots available to the public in this forum?"

As noted above we did not have a fast response thermocouple in the resonant cavity to monitor fast air temp changes, but the outside IR camera data indicates that the internal air temp probably stabilized around a mean aluminum case temperature of ~88F after about 90 minutes of on/off cycling operation.  We also found that after the cylindrical aluminum cavity reached its running temp, we did not have to continue adjusting the cavity RF tuning to maintain its 30W of input power at 1.48 GHz.

BTW, the Eagleworks 6061 aluminum cylindrical cavity used in this experiment has machined 0.25" thick endplate walls and cylinder, so it has proven to be very stable once it has reached its run temp.  I.e., there is over 2.5kg of thermal mass in this cavity design that reduces fast temp shifts.

Best, Paul M.

Correction:

I said Previously in this post:

"After determining this thermal rise time constant with our IR camera, we let the test article warm up for approximately one hour before starting our data acquisition of 27,000 to 30,000 ~1.5 second on/off cycles with each on/off cycle resulting in a CCD camera picture with a few examples shown in the attached FFTs of Imager slide."

This is what I get when I try to translate another persons work.  By that I mean after talking with Dr. White this morning, I realized I made an error in my above summary of the interferometer data acquisition process.  That being the 27,000-to-30,000 on/off cycles do NOT create an x-y "puddle plot" for every on/off cycle.  Instead all 27,000+ on/off samples are averaged over four active points on the ~1280 x 960 CCD pixel array and then averaged to make the associated FFT frequency plot from 0-to-5 Hz.  Sonny is now in the process of coming up with an average and peak data analysis technique that will use ALL the CCDE pixels instead of just four per frame.  Oh yes, and develop an algorithm that doesn't take 100 years to process on his laptop.  :)

Best, Paul M.
« Last Edit: 04/22/2015 03:53 AM by Star-Drive »
Star-Drive

Offline Star-Drive

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I thought I would post a graphic I made of a light cone.  If I am correct for normal warp the cone just flattens suggesting that the observed mote/traveler could move some maximum distance from their original location at some later time.   

I would imagine a tilted warp cone might happen where space is swirling around a rotating black hole and drags objects around it.  If that space reaches light speed or above then the space moving away looks like an event horizon while the space moving towards us is blue-shifted in spectrum.  If the space is moving away at less than c then it should be red-shifted.  In that case if one sits still in moving space then they are moving so the axis is tilted.  (I guess if our space is expanding this suggest we might have tilted light cones?) I don't know that if the central axis is tilted beyond 45 degrees that the light cone would necessarily cross the plane.  I would think light would appear to move at 2*c, 2=m, from an outside observer in one direction and not move at all the other direction m=0 (space is moving against it and it gets nowhere).  That would suggest some distortion of our light cone but that it's not crossing the plane where the slope m = infinity. 

I would think it would require infinite energy to get to warp infinity.  Hopefully I'm not too far off here. 

When considering the use of EM-drives in the making of warp-drives the attached two papers might be of interest.

In the meantime, back to figuring out how to reliably drive an EM-drive...

Edit:  You might also like to read Sonny's Warp-field Mechanics 101 and 102 articles.
http://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/20130011213.pdf

Best, Paul M.
« Last Edit: 04/21/2015 12:17 PM by Star-Drive »
Star-Drive

Offline Rodal

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Is the Cannae drive effort still ongoing ? Any news on Cannae?

Cannae's website ( http://cannae.com/ ) gives today an Internal Server Error.

Cannae's twitter account ( https://twitter.com/cannaeqdrive ) last twit was dated May 12 2014, practically a year ago.

Last video uploaded by Cannae to their Vimeo page was one year ago:

https://vimeo.com/cannae/videos

The wayback machine cannot longer display previous entries like this one (quoted on the wikipedia EM Drive article):

http://web.archive.org/web/20121102082714/http://www.cannae.com/proof-of-concept/experimental-results

due to the Robots exclusion standard.

One cannot get much information from the Bloomberg page on Cannae LLC:

http://www.bloomberg.com/research/stocks/private/snapshot.asp?privcapId=134038401

or in Manta:

http://www.manta.com/c/mwfq0td/cannae-llc

Also, I thought that at one time there was a Wikipedia page for Cannae's drive: either my memory is incorrect or the Wikipedia Cannae drive page has been removed or if it exists, I can't find it.  The EM Drive and Quantum vacuum plasma thruster Wikipedia pages remain (albeit both containing strong Wikipedia warnings about their quality).

« Last Edit: 04/21/2015 07:53 PM by Rodal »

Offline Rodal

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....
BTW, we are going to add optical borosilicate telescope grade flat windows to the ends of the RF chokes when we get around to pulling a vacuum in this 1.48 GHz resonant cavity.
....
Best, Paul M.

Issues like this (and several other practical difficulties) associated with doing this experiment in a partial vacuum, lead me to suggest to do different experiments of path length measurement, in the interim, in different inert gas environments, each having different refraction properties. 

Doing the same path length measurements, but this time in different inert gas environments may serve to put to bed the issue of the interferomenter measurements being due to refraction.

http://en.wikipedia.org/wiki/Kerr_effect

http://www.sciencedirect.com/science/article/pii/S0030401814003794

attachment:

Measurement of pressure dependent nonlinear refractive index of inert gases
Á. Börzsönyi,1 Z. Heiner,1,2 A.P. Kovács,1 M. P. Kalashnikov3 and K. Osvay1,*

« Last Edit: 04/22/2015 12:52 AM by Rodal »

Online Chris Bergin

So we're over 300,000 views on this thread now. Sure, a SpaceX thread - for example - can do that sort of level and more, but for an advanced topic thread this is rare.

The item of interest is a huge amount of NASA IPs have been hitting this thread over the past number of days. I know we already have a lot of NASA on here, but my experience says there's been a memo or such that has pointed NASA folk to this thread. If any of you wish to let me know, hit me up on PM. Previous experience of that sort of thing is where they add a "and a cool item being discussed on X site is...." at the end of a ViTS or "8th Floor" style memo. Would be nice to see if it's been linked as such.

(EDIT: Found out it was a NASA pointer brief, but no specific reference other than a link about "ongoing EM Drive conversations").

And yes, we are still working an article on this. Long process as the subject matter is pretty hard to translate to the wide audience of the news site.

EDIT: *Lots* of people turning up today, mainly social media like Reddit subs, Twitter, Google, the whole works, even Star Trek fans (I kid you not!) - all at the same time. I can see the referrals on our server stats, so no need to let me know (lots of PMs about it today, but nice to hear from new folk :) ).

Offline Star-Drive

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BTW, we are going to add optical borosilicate telescope grade flat windows to the ends of the RF chokes when we get around to pulling a vacuum in this 1.48 GHz resonant cavity.
....
Best, Paul M.

Issues like this (and several other practical difficulties) associated with doing this experiment in a partial vacuum, lead me to suggest to do different experiments of path length measurement, in the interim, in different inert gas environments, each having different refraction properties. 

Doing the same path length measurements, but this time in different inert gas environments may serve to put to bed the issue of the interferomenter measurements being due to refraction.

http://en.wikipedia.org/wiki/Kerr_effect

http://www.sciencedirect.com/science/article/pii/S0030401814003794

attachment:

Measurement of pressure dependent nonlinear refractive index of inert gases
Á. Börzsönyi,1 Z. Heiner,1,2 A.P. Kovács,1 M. P. Kalashnikov3 and K. Osvay1,*


Dr. Rodal:

Thanks for the nonlinear refractive index of inert gases paper.  I'll pass it along to Dr. White and Dr. Rollins, but I'm sure they have already committed themselves to drawing at least a 1x10^-3 Torr vacuum in the 1.48 GHz cylindrical cavity for their next test series as soon as the parts for same show up.

On anther related front, today at our Eagleworks staff meeting we kicked around the idea of using a high resolution piezoelectric actuator to calibrate the magnitude of the space-time contractions that the 1.48 GHz resonant cavity might be generating.  As is we only have a qualitative measure of the magnitude of the path length contractions using the current interferometer setup.  However if we added the aforementioned piezo-actuator with a repeatable displacement resolution of at least a nanometer (nm) to one of the interferometer mirror mounts, we could turn off the resonant cavity and emulate its space-time contractions using the piezo driven mirror with the same timed on/off cycles using first, say a known +/-1.0 nm oscillation of the attached mirror, and then see what this piezo driven displacement magnitude drives in the FFT response of interferometer.  Once we know how much ac E-field in the cavity it takes to drive x.x  space-time contractions in the cavity, we can then start to populate the curve required to determine the degree of non-linearity there is in this forcing function and whether it matches Dr. White's Q-V conjecture predictions.

Best,  Paul M.
« Last Edit: 04/22/2015 12:04 PM by Star-Drive »
Star-Drive

Offline zen-in

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In the late 70's I worked for a company that made FTIR spectrometers.   They use small aperture interferometers for a laser and white light source to locate the position of the moving mirror and to trigger the A/D sampling.   A laser interferogram is a sine wave while the white light interferogram is a sinc function with a prominent peak.   The trick to achieving stable sampling is to position the sinc peak midway between two laser interferogram peaks so that any thermal drift does not result in a sample point jump.   The best long term stability I was able to achieve with a Digilab interferometer was +/- 40 nM shift in the laser peak wrt to the white light peak over a 24 Hr. period.   That interferometer was used on the KAO.   However during the test it was mounted in a covered and temperature controlled optical table.   The mirror mounts were specially designed to dampen vibrations.   With an air bearing Michelson interferometer (one mirror moving) the precision can be monitored.   The very small phase shifts ( a few nM) measured by the Eagleworks team as the magnitude of the space-time contractions are more than an order of magnitude below the best positional accuracy a well designed interferometer is capable of.    To validate this measurement I would suggest using an FTIR spectrometer in a dual sampling mode and with the laser as the source.   An additional reference would be the smaller laser interferometer used for A/D sampling.
« Last Edit: 04/22/2015 05:34 AM by zen-in »

Offline Rodal

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In the late 70's I worked for a company that made FTIR spectrometers.   They use small aperture interferometers for a laser and white light source to locate the position of the moving mirror and to trigger the A/D sampling. ...  The best long term stability I was able to achieve with a Digilab interferometer was +/- 40 nM shift in the laser peak wrt to the white light peak over a 24 Hr. period.   That interferometer was used on the KAO.   However during the test it was mounted in a covered and temperature controlled optical table.   The mirror mounts were specially designed to dampen vibrations.   With an air bearing Michelson interferometer (one mirror moving) the precision can be monitored.   The very small phase shifts ( a few nM) measured by the Eagleworks team as the magnitude of the space-time contractions are more than an order of magnitude below the best positional accuracy a well designed interferometer is capable of.   ...

There are several problems requiring measurement of changes in the optical path length with nanometer precision, for example:  A)  microelectromechanical system microdevices, from microscanners to micromotors, B) nanometer walk (piconewton force) in biological micromotors, C) the determination of the mechanical transfer function of low-mass cantilevers for data storage devices, and D) accurate determination of the transfer function for the pendular suspension used for the mirrors in gravitational wave interferometers.

State-of-the-art interferometers sensitive enough to measure displacements below 1 Hz with a RMS error of approximately 1 nanometer were reported 15 years ago.
« Last Edit: 04/22/2015 02:53 PM by Rodal »

Offline mvpel

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QUESTION 2: If so, did the observed anomalous peak in the Power Spectral Density occur at a frequency in accordance with the time taken to energize  and de-energize?

Yes, the on/off cycle time was around 1.5 seconds with some uncertainty due to Windows 7.0 time outs.  Need a real time operating system (RTOto clear that problem, a RTOS system we don't have.

We use Red Hat Enterprise MRG Realtime for our application, and the CentOS project provides a free rebuild version of the Red Hat "kernel-rt" package set which you can install. This site http://dev.centos.org/~z00dax/mrg/ has RPMs for it, but seems a little out of date - the latest RHEL kernel-rt is 3.10.58 - but the free one would probably suit your purposes. It can be a little finicky about hardware sometimes, so you'd want to take that into consideration.
“This one went unusually smoothly. When I finished it, I remarked to a friend that I felt like an engineer who had designed a machine and then sat back and realized it did everything I'd set out to do. Which made him say, quite emphatically, "No engineer has ever felt this.”
― Robert J. Bennett, Galileo Was Wrong

Offline Rodal

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QUESTION 2: If so, did the observed anomalous peak in the Power Spectral Density occur at a frequency in accordance with the time taken to energize  and de-energize?

Yes, the on/off cycle time was around 1.5 seconds with some uncertainty due to Windows 7.0 time outs.  Need a real time operating system (RTOto clear that problem, a RTOS system we don't have.

We use Red Hat Enterprise MRG Realtime for our application, and the CentOS project provides a free rebuild version of the Red Hat "kernel-rt" package set which you can install. This site http://dev.centos.org/~z00dax/mrg/ has RPMs for it, but seems a little out of date - the latest RHEL kernel-rt is 3.10.58 - but the free one would probably suit your purposes. It can be a little finicky about hardware sometimes, so you'd want to take that into consideration.

The latest real time offering from Red Hat is here:
https://access.redhat.com/products/red-hat-enterprise-linux/realtime

The Red Hat realtime kernel is designed for environments which require low latency and more predictability than a generic OS. Apparently, financial companies (banks / hedge funds) use Red Hat realtime kernels (sometimes with their own modifications) for their trading purposes (perhaps high frequency trading, but obviously they keep their purposes confidential). 

Is a device driver for the instrument also involved in the interferometer tests ?

If a device driver for the instrument is also involved one may be stuck with whatever RTOS the instrument maker recommends (unless it is some generic interface). Also, embedded RTOS are used by various telecommunication companies.

(Any credit for this information goes to D.W. and any errors in it belong exclusively on my shoulders).
« Last Edit: 04/22/2015 04:09 PM by Rodal »

QUESTION 2: If so, did the observed anomalous peak in the Power Spectral Density occur at a frequency in accordance with the time taken to energize  and de-energize?

Yes, the on/off cycle time was around 1.5 seconds with some uncertainty due to Windows 7.0 time outs.  Need a real time operating system (RTOto clear that problem, a RTOS system we don't have.

We use Red Hat Enterprise MRG Realtime for our application, and the CentOS project provides a free rebuild version of the Red Hat "kernel-rt" package set which you can install. This site http://dev.centos.org/~z00dax/mrg/ has RPMs for it, but seems a little out of date - the latest RHEL kernel-rt is 3.10.58 - but the free one would probably suit your purposes. It can be a little finicky about hardware sometimes, so you'd want to take that into consideration.

There is also a free versions of RTOS available: http://www.freertos.org/

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