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#4000
by
RERT
on 21 Jul, 2016 19:48
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My bad, sloppy language. I never expected an 'official' response from NASA. My impression, correct or otherwise, is that lots of NASA people and other aerospace types who know infinitely more than I do about spaceflight might reading and be able to comment, in a personal capacity.
If anyone knows the specs of the best current tech thruster which might fit in a 6U cube sat, I would be interested to know.
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#4001
by
zen-in
on 21 Jul, 2016 20:33
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My bad, sloppy language. I never expected an 'official' response from NASA. My impression, correct or otherwise, is that lots of NASA people and other aerospace types who know infinitely more than I do about spaceflight might reading and be able to comment, in a personal capacity.
If anyone knows the specs of the best current tech thruster which might fit in a 6U cube sat, I would be interested to know.
Besides the big springs that eject each cubesat, there have been several proposed thrusters. Last year I attended a talk on a compact plasma thruster called the cubesat ambipolar thruster. No space trials had been done. There may be several parallel projects in different countries. Another type of small thruster, which has gotten funding from NASA is the microblister thruster (I may have the name wrong). It has many small (one-time) electric discharge sites on a small flat panel. Each time an electric discharge occurs debris is ejected, creating thrust. Of course the discharge is distributed over a half spherical volume so would be diffuse. Another thruster proposal is Mason Peck's (a U. Rochester aero prof and former NASA CTO) Lorentz thruster. Miller (an MIT aero prof and current NASA CTO) has proposed satellite station-keeping (inter-satellite thrust, ie:multiple satallites pushing and pulling each other) using superconducting coils. Solar sails have also been deployed on larger specially designed satellites. They may find use on cubesats. Many, if not all cubesat propulsion ideas fall in the category of wanting your cake and eating it to.
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#4002
by
Tellmeagain
on 21 Jul, 2016 21:07
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My bad, sloppy language. I never expected an 'official' response from NASA. My impression, correct or otherwise, is that lots of NASA people and other aerospace types who know infinitely more than I do about spaceflight might reading and be able to comment, in a personal capacity.
If anyone knows the specs of the best current tech thruster which might fit in a 6U cube sat, I would be interested to know.
Besides the big springs that eject each cubesat, there have been several proposed thrusters. Last year I attended a talk on a compact plasma thruster called the cubesat ambipolar thruster. No space trials had been done. There may be several parallel projects in different countries. Another type of small thruster, which has gotten funding from NASA is the microblister thruster (I may have the name wrong). It has many small (one-time) electric discharge sites on a small flat panel. Each time an electric discharge occurs debris is ejected, creating thrust. Of course the discharge is distributed over a half spherical volume so would be diffuse. Another thruster proposal is Mason Peck's (a U. Rochester aero prof and former NASA CTO) Lorentz thruster. Miller (an MIT aero prof and current NASA CTO) has proposed satellite station-keeping (inter-satellite thrust, ie:multiple satallites pushing and pulling each other) using superconducting coils. Solar sails have also been deployed on larger specially designed satellites. They may find use on cubesats. Many, if not all cubesat propulsion ideas fall in the category of wanting your cake and eating it to.
Don't forget the easiest kind of thruster, a can of compressed gas.
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#4003
by
SeeShells
on 21 Jul, 2016 22:43
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https://www.academia.edu/11093756/Confinement_of_Light_Standing_Wave_Transformations_in_a_Phase-Locked_ResonatorStanding electromagnetic waves in a phase-locked resonator have been shown to explain the origin of mass and inertia while standing wave interactions between coupled resonators provide an explanation for the origin of gravity. In this paper, the focus is on the internal dynamics of an isolated resonator. Properties of light when confined within a phase-locked cavity are reviewed and graphical representations of Lorentz contracted standing waves of phase-locked cavity resonators in motion are portrayed. Radiation and propagation characteristics of EM waves are briefly reviewed and illustrated. Motion of a phase-locked resonator with phase conjugate mirrors is described. Potential for induced motion of a phase-locked, phase conjugate resonator by energy input of pump beams of simulated Doppler shifted frequencies is discussed.
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#4004
by
mwvp
on 22 Jul, 2016 02:56
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#4005
by
SeeShells
on 22 Jul, 2016 03:01
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#4006
by
mwvp
on 22 Jul, 2016 04:21
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https://www.academia.edu/11093756/Confinement_of_Light_Standing_Wave_Transformations_in_a_Phase-Locked_Resonator
...
Sounds like an interesting paper
...
Here you go warning .pdf
Thank-you very much.
I'll have to give it some time and attention. At a glance, it discusses Doppler shifts causing unbalanced radiation pressure, (alas, anisotropic dispersion and dissipation) and speaks to what I believe is going on, and is discussed in the paper on Optomechanics I've refered to.
A problem with a physical model of a particle as a soliton/oscillon is, a particle can pass through one slit of a double slit and manifest the spooky sum-of-all-paths quantum delocalization and wave collapse.
The answer to that is, the particle is a
dark soliton/oscillon, in a hot vacuum-plasma that also speaks to Hiesenburg uncertainty.
A while ago, Rodal asked if there was any example of non-Newtonian reaction-originated motion. I almost replied, "well, yes... every freek'in Fermion particle in the universe"
. I of course didn't since I didn't feel up to explaining my reasoning, but this paper speaks to the EM basis for motion and inertia.
I was thinking too, wouldn't a radio signal from a receding horn antenna be Doppler-shifted lower in frequency, thus providing radiation-reaction impulse to the horn, increasing the efficiency of the "photon-rocket" by an analogous principle to the rocket engine nozzle, albeit matching impedance rather than pressure? If you imagine a photon as a localized particle rather than a delocalized wave, it won't make sense.
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#4007
by
SeeShells
on 22 Jul, 2016 04:58
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https://www.academia.edu/11093756/Confinement_of_Light_Standing_Wave_Transformations_in_a_Phase-Locked_Resonator
...
Sounds like an interesting paper
...
Here you go warning .pdf
Thank-you very much.
I'll have to give it some time and attention. At a glance, it discusses Doppler shifts causing unbalanced radiation pressure, (alas, anisotropic dispersion and dissipation) and speaks to what I believe is going on, and is discussed in the paper on Optomechanics I've refered to.
A problem with a physical model of a particle as a soliton/oscillon is, a particle can pass through one slit of a double slit and manifest the spooky sum-of-all-paths quantum delocalization and wave collapse.
The answer to that is, the particle is a dark soliton/oscillon, in a hot vacuum-plasma that also speaks to Hiesenburg uncertainty.
A while ago, Rodal asked if there was any example of non-Newtonian reaction-originated motion. I almost replied, "well, yes... every freek'in Fermion particle in the universe" . I of course didn't since I didn't feel up to explaining my reasoning, but this paper speaks to the EM basis for motion and inertia.
I was thinking too, wouldn't a radio signal from a receding horn antenna be Doppler-shifted lower in frequency, thus providing radiation-reaction impulse to the horn, increasing the efficiency of the "photon-rocket" by an analogous principle to the rocket engine nozzle, albeit matching impedance rather than pressure? If you imagine a photon as a localized particle rather than a delocalized wave, it won't make sense.
I was thinking too, wouldn't a radio signal from a receding horn antenna be Doppler-shifted lower in frequency, thus providing radiation-reaction impulse to the horn, increasing the efficiency of the "photon-rocket" by an analogous principle to the rocket engine nozzle, albeit matching impedance rather than pressure? If you imagine a photon as a localized particle rather than a delocalized wave, it won't make sense.
Although to the horn the radio signal is operating normally, it has no idea it's receding nor does any of the actions it may impart to the horn.
every freek'in Fermion particle in the universe"
I had to chuckle at this and I might be over my pay grade even trying to dig through papers in just how the Weyl fermion (just discovered in 2015) could be a major game player. You're way past me my dear and my hat's off to you.
Shell
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#4008
by
Augmentor
on 22 Jul, 2016 09:03
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With all the experiments going on, I'm wondering if radiation forces are being included and identified. Possible Radiation forces to take into consideration at both micro and macro scales are:
Radiation pressure - E and/or B waves on the surface
Surface plasmon resonance - Surface effect
Radiation resistance - for any antenna
Radiation reaction - Sum of Abraham-Lorentz force and Poynting–Robertson force
See Fearn 2012
https://arxiv.org/pdf/1212.4469.pdfOther possible radiation reactions are being researched.
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#4009
by
RERT
on 22 Jul, 2016 09:44
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Thanks to the kind soul who suggested I might get somewhere by googling Cubesat propulsion...
At cubesat-propulsion.com the best ~1U propulsion unit seems to do around 1800 Ns total impulse.
My calculated drag force over 6 months is 469-3597 Ns. Given the will to use 2U or more for propulsion, as guessed the mission is not impossible off-the-shelf. They would have to fly lower or longer to out-perform substantially: a year at 180km up maybe?
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#4010
by
VAXHeadroom
on 22 Jul, 2016 11:22
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Thanks to the kind soul who suggested I might get somewhere by googling Cubesat propulsion...
At cubesat-propulsion.com the best ~1U propulsion unit seems to do around 1800 Ns total impulse.
My calculated drag force over 6 months is 469-3597 Ns. Given the will to use 2U or more for propulsion, as guessed the mission is not impossible off-the-shelf. They would have to fly lower or longer to out-perform substantially: a year at 180km up maybe?
180Km is a very VERY low orbital altitude. The ISS orbits about 400Km. Honestly, I don't even know how you'd get INTO such a low orbit - most ride-share deployers will deploy cubesats in whatever final orbit they are deploying the primary satellite and they would have to do that after the final engine cutoff. 300+ Km would be typical...
Busek probably has the most mature cubesat thrusters I've seen.
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#4011
by
Rodal
on 22 Jul, 2016 13:21
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Thanks to the kind soul who suggested I might get somewhere by googling Cubesat propulsion...
At cubesat-propulsion.com the best ~1U propulsion unit seems to do around 1800 Ns total impulse.
My calculated drag force over 6 months is 469-3597 Ns. Given the will to use 2U or more for propulsion, as guessed the mission is not impossible off-the-shelf. They would have to fly lower or longer to out-perform substantially: a year at 180km up maybe?
180Km is a very VERY low orbital altitude. The ISS orbits about 400Km. Honestly, I don't even know how you'd get INTO such a low orbit - most ride-share deployers will deploy cubesats in whatever final orbit they are deploying the primary satellite and they would have to do that after the final engine cutoff. 300+ Km would be typical...
Busek probably has the most mature cubesat thrusters I've seen.
===>I agree that the propulsion thrust that can be generated by the Cannae drive (according to NASA's 2014 data) is insufficient to clearly be above the drag forces at this altitude, which are difficult to precisely quantify and therefore testing the EM Drive at this altitude is not ideal<===
However, to clarify:
The announcement (
http://cannae.com/cannae-is-developing-a-cubesat-thruster/) from Cannae states:
Theseus Space Inc. will use Cannae thruster technology to maintain (for a minimum of 6 months) the orbit of a 6U cubesat flying below a 150 mile orbital altitude.
150 miles is
241 km , not 180 km . A mile is approximately 1.6 km.
It is unfortunate that Cannae is using miles as a unit instead of km, as this naturally leads to confusion, as SI units are used predominantly nowadays.
241 km is above the minimum Low Earth Orbit: defined as an orbit around Earth with an altitude between 160 kilometers (99 mi) (orbital period of about 88 minutes), and 2,000 kilometers (1,200 mi) (about 127 minutes).
As an example Antares A-One, launched from Wallops Island in 2013, deployed 4 CubeSats from the CMS into an orbit "approximately 150 by 160 miles" (240 km x 260 km) with an inclination of 51.6 degrees.
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#4012
by
MaxIsp
on 22 Jul, 2016 13:22
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Thanks to the kind soul who suggested I might get somewhere by googling Cubesat propulsion...
At cubesat-propulsion.com the best ~1U propulsion unit seems to do around 1800 Ns total impulse.
My calculated drag force over 6 months is 469-3597 Ns. Given the will to use 2U or more for propulsion, as guessed the mission is not impossible off-the-shelf. They would have to fly lower or longer to out-perform substantially: a year at 180km up maybe?
180Km is a very VERY low orbital altitude. The ISS orbits about 400Km. Honestly, I don't even know how you'd get INTO such a low orbit - most ride-share deployers will deploy cubesats in whatever final orbit they are deploying the primary satellite and they would have to do that after the final engine cutoff. 300+ Km would be typical...
Busek probably has the most mature cubesat thrusters I've seen.
JAXA is planning launch of Super Low Altitude Test Satellite (SLATS) as a piggyback on GCOM-C launch to altitude above 600km then lowering its altitude to 200km. Its mission is to study the atmosphere at this level and requires significantly more altitude maintenance propellant.
http://global.jaxa.jp/projects/sat/slats/An issue with this altitude level is that the atmospheric drag changes substantially over a year and due to changes to space weather, radiation, and solar wind. For testing a EM drive powered spacecraft you would want to be at as high an altitude as possible because the changes to orbital elements due to propulsive maneuvers would be provide more useful measurements than trying to figure out the effects of atmospheric drag with all its variabilities.
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#4013
by
RERT
on 22 Jul, 2016 15:51
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Hi - I was aware the orbit was 150 miles (240km) and calculated the drag at that altitude.
I suggested 180km as a 'lower for longer' mission, which would more quickly single out their satellite as likely propellant-less. I said that on the basis that drag would be a multiple (six times by my estimates) of drag at 240km. I'm aware that a 240km orbit in itself is very low, with an apparent un-powered life of only a few days.
On reflection there is no reason to suppose that they can generate the larger thrust required to stabilize a 180km orbit, so beating current thruster total impulse (soon) isn't everything.
However one must assume that, if their web post is accurate, they are confident of a long-time average thrust which is greater than the drag at 240km, probably with some decent margin for error. Unlikely to be less than 100 μN.
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#4014
by
JonathanD
on 22 Jul, 2016 16:34
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If it were to be launched at a higher altitude orbit, say 500km, how long would it take to get down to 240km with the implied thrust sufficient for station keeping at that altitude?
Also I wonder why they picked the seemingly-arbitrary 6 months? If it works as they say it does wouldn't they be able to hold that orbit perpetually?
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#4015
by
tchernik
on 22 Jul, 2016 17:20
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If it were to be launched at a higher altitude orbit, say 500km, how long would it take to get down to 240km with the implied thrust sufficient for station keeping at that altitude?
Also I wonder why they picked the seemingly-arbitrary 6 months? If it works as they say it does wouldn't they be able to hold that orbit perpetually?
If they can manage to overcome atmospheric drag, I'd keep pushing the satellite upwards as long as it has electrical juice. And why not? even send it to an ever higher orbit into interplanetary space. That would make a lot of heads turn.
But probably they don't expect to overcome atmospheric drag forever. Just enough for making a verifiable statement about their tech.
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#4016
by
WarpTech
on 22 Jul, 2016 17:30
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....
I don't miss the embarrassing mistakes though! I'm being very careful to be concise and check my work thoroughly. Anyone willing to referee my paper and give me some feedback before I finalize, send me a PM and I'll forward the draft to you. It's not ready yet, but almost...
Thanks!
Todd
Thanks to those who commented on the typos. I posted the paper to Research Gate for anyone interested. I have more material to add to this before I try to publish it, but it will have to wait until I have time to do the research and compile the rest of the data. This will have to do for now. I think it provides an interesting perspective and a new set of tools for engineers to think about regarding gravity.
https://www.researchgate.net/publication/305501551_AN_ENGINEERING_MODEL_OF_QUANTUM_GRAVITYI welcome any comments you may have.
Enjoy!
Todd
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#4017
by
FattyLumpkin
on 22 Jul, 2016 18:35
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RERT, please help me with this one...TBMK the government has to approve what Theseus Space Inc. (TSI) wants to launch to LEO Yes? , and that they have to know all of the particulars in the cubesat (contents) Yes? If this is the case is the government obligated to disclose what's in the package?--as I understand the govt. looks at space in the same way they do the air waves (they belong to the people). Not to mention there are security concerns: kinetic energy weapons, bombs etc. Cannae strikes me as being just a little too slick, and I have my doubts.
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#4018
by
rfmwguy
on 22 Jul, 2016 19:34
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http://tinyurl.com/j3cqsbgSalt Palace Convention Center, Salt Lake City, Utah 25 - 27 July 2016
NFF-05. Future Flight Propulsion Systems I
Chair(s): Bryan Palaszewski (NASA Glenn Research Center)
Co-Chair(s): Brice Cassenti (University of Connecticut)
7:00 PM - 7:30 PM
AIAA-2016-4917. WWAT: Warp Drives, Wormholes, Antigravity and Time Travel
Brice N. Cassenti
http://www.enthea.org/docs/Warp-Drives-Engineering.pdf"CONCLUSIONS
A warp drive would, not only, allow travel faster than the speed of light but warping spacetime could also reduce or cancel gravity, provide artificial gravity, and allow for propulsion without the use of a propellant. The first steps must include an examination of the physics in detail, and any extensions of physics that can unite electromagnetism with matter and gravity. If a source cannot pick up, or dump, momentum to the universe, or the vacuum, then it may not be possible to construct warp drives, and if electromagnetism cannot be readily used to warp space then the construction of a warp drive will require enormous energy densities over significant volumes. Hence, if the physics works out, the best path to a warp drive includes using the vacuum as source of momentum and applying electromagnetic fields to warp the spacetime."
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#4019
by
Star One
on 22 Jul, 2016 20:52
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I had to chuckle at this and I might be over my pay grade even trying to dig through papers in just how the Weyl fermion (just discovered in 2015) could be a major game player. You're way past me my dear and my hat's off to you.