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#40 by Paul451 on 14 May, 2015 04:43
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Once you've definitively proven the effect real, you don't need a puny few million dollar prize to stimulate development, you'll have the entire aerospace industry pushing it (even if its limited to millinewtons it would revolutionise space travel.)
What I can't see is how you could define a test, in a way that would satisfy the lawyers, at any level of thrust that hasn't already unequivocally proven the effect is real. Either you open yourself to ambiguous results (and lawsuits), fraud (and lawsuits), or the demonstration will need to be 100pts on a scale where 10pts is enough to have already convinced people with real money. The prize becomes pointless, either being soft and therefore ambiguous, or only being claimable when it no longer matters. It seems to be a Catch-22 situation.
To use an analogy: It's like proposing the Orteig Prize (Atlantic crossing) as the level of demonstration necessary to "prove" the claims of the Wright Bros. By the time anyone is able to claim the prize, the basic claim "powered flight is real" is long, long proven beyond a shadow of a doubt; and probably already in commercial use. So what is the point of the prize?
Or another analogy: It's like the original X-Prize (flight to 100km) was offered before chemical-rockets were proven to exist. By the time someone could meet the terms of the prize, the idea of rockets will have been long since proven to everyone's satisfaction. The prize doesn't actually add anything. -
#41 by Star One on 14 May, 2015 06:40
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I think it's a big mistake by the X-Prize foundation to become involved in this proposed prize.
First of all, it's choosing a technology instead of leaving it open to any technology. It's specifically saying it's for an "EM Drive". That would be like having the original X-Prize specify a liquid-engine rocket, which would have excluded SpaceShipOne.
Prizes like the X-Prize work best when they specify only the end result that has to be achieved and leave the means to do so as open as possible.
Secondly, it's associating the X-Prize brand with a highly controversial specific technology. Part of the whole point of the X-Prize is to bring respectability to New Space. By associating its brand with a specific technology that the vast majority of professional scientists consider to be a crackpot idea, they are diminishing the X-Prize brand. It gives ammunition to those in the aerospace establishment to belittle anything associated with the X-Prize, and that hurts all the companies trying to raise money for lunar rovers, space launch, and anything else the X-Prize offers a prize for.
I don't think this bringing respectability to New Space you mention is anything to do with the intentions of the X-Prize. It's about straight up innovation not bestowing respectability on things, least of so called new space. And don't even get me started on terms like new space, which is just another meaningless buzzword. There's just the space industry no need to artificially separate things into old & new. -
#42 by sghill on 14 May, 2015 14:43
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I love the Examiner article. How flattering that the little NSF forum carries enough cachet that it is generating mainstream press in real time from our posts.
Regarding the utility of the prize itself in response to Paul451. Your analogies are inaccurate, even though I see where you are coming from.
First, the potential for prize money reduces development risk, which in turn makes it easier to attract money to fund one, and perhaps many, development teams. The risk that another team still wins is there, but the absolute risk that nothing will come of making the effort is lowered. For example, 45% of angel investor money goes to companies that are not selling, but are near to market. Yet only 5% goes to true startups. The point here is that a near market company has already "invented" it's product offering, but it's not selling yet. It's risk of failing in the market place is still there, but the initial development risk is lower, so it's an attractive investment opportunity. Similarly, an X-prize lowers development risk by creating a set opportunity for reward, but it doesn't affect market risk. I.e. Virgin Galactic is still a very risky market proposition, even though the technology they are using was initially developed to capture x-prize money.
Second, and relatedly, a development prototype that meets the judging criteria for winning is not necessarily a good design for the marketplace, and my first point applies. However, the entire point of the prize is to spur development of the technology that otherwise would not have occurred. -
#43 by Lumina on 14 May, 2015 15:34
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I also believe that a cubesat is the best way to go for an X-prize. Prove constant mass and constant thrust of at least x.xxx N over minimum t length of time (starting from LEO). Thrust benchmark would have to be an order of magnitude above known effects such as the best-case photon rocket. Time and trajectory goals should be selected to indirectly and conclusively rule out all other known propellantless thrusting techniques.
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#44 by jordan.greenhall on 14 May, 2015 15:37
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Nice. Any reason why you think .1N is the right number? Why not 1N or higher? My sense is that there is some thrust > X where reasonable alternative explanations drop away and we are left with a "this is clearly something new" result. Why do you think that .1N is X?
Why vacuum? Obviously it will be important for space operations that one be able to operate this thing in a vacuum - but for the purposes of proving that we have a "something new result," what does a vacuum add? If thrust is > X, don't all of the things that a vacuum would help eliminate already drop away?
Portable is a nice interesting objective. The deep intent here is to allow 3rd parties to ask for a test of the rig in their own environment?
What I'm seeing so far in this thread (other than a funny need of people to contribute to the thread that they think that an X-prize is a bad idea!) is:
* Thrust > X
* Extremely repeatable
* For some long time and number of repetitions
* Highly transparent and available to be "prodded" by 3rd partiesBeing able to generate at least 10g / 0.1N of thrust EVERY time it is powered on, do that for 1,000 cycles, do it in a vacuum, generate thrust that you can feel with your hand in air, in a portable rig that can be easily transported to any test lab on the planet, tests and data captures streamed live over the net with open comments and discussion as the tests are happening, will be enough to cause an avalanche of further research.
That is my replication goal. -
#45 by jordan.greenhall on 14 May, 2015 15:41
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Chris, you seem to have assumed your objections.
a) It can be branded anything. If you think that calling it an "EM Drive" X-prize is troubling, please suggest what you think might be better.
b) The specific ask of this thread is for assistance on specifying the end result to be achieved. The necessity of not binding to an implementation is well understood. Do you have any specific suggestions here?
c) Keeping in mind the above also don't worry too much about the X-prize and their association with risky endeavours. That is their raison d'etre. They know that this has a small chance of success and are delighted by the prospect. They are all about high risk / high reward innovation.I think it's a big mistake by the X-Prize foundation to become involved in this proposed prize.
First of all, it's choosing a technology instead of leaving it open to any technology. It's specifically saying it's for an "EM Drive". That would be like having the original X-Prize specify a liquid-engine rocket, which would have excluded SpaceShipOne.
Prizes like the X-Prize work best when they specify only the end result that has to be achieved and leave the means to do so as open as possible.
Secondly, it's associating the X-Prize brand with a highly controversial specific technology. Part of the whole point of the X-Prize is to bring respectability to New Space. By associating its brand with a specific technology that the vast majority of professional scientists consider to be a crackpot idea, they are diminishing the X-Prize brand. It gives ammunition to those in the aerospace establishment to belittle anything associated with the X-Prize, and that hurts all the companies trying to raise money for lunar rovers, space launch, and anything else the X-Prize offers a prize for. -
#46 by jordan.greenhall on 14 May, 2015 15:48
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Paul, I don't follow. Specifically, I don't see where lawyers come into the discussion.
In any event, let me walk through the current logic and lets see if we can connect:
1) The effect has clearly not yet been proven real. Specifically, the current level of "proof" is inadequate to have kicked off a "race" within the industry (at least so far as we know). The vast majority of relevant outside observers (e.g., physicists) continue to dismiss it as not real.
2) There is some threshold where the effect will have moved past some tipping point of "proof" that is adequate to significantly increase research activity.
3) This threshold clearly is beyond the current level of demonstration; and is *hopefully* within the range of possibility that could be motivated by a $1M - $3M X-prize.
4) If this threshold has been passed we are in a very different environment and should expect substantial activity around the effect.
Earlier in this thread, I've outlined what appears to be the emerging consensus as to what that threshold looks like.
To use your analogy, we are currently *before* kitty hawk and the point of the X-prize is precisely kitty hawk.Once you've definitively proven the effect real, you don't need a puny few million dollar prize to stimulate development, you'll have the entire aerospace industry pushing it (even if its limited to millinewtons it would revolutionise space travel.)
What I can't see is how you could define a test, in a way that would satisfy the lawyers, at any level of thrust that hasn't already unequivocally proven the effect is real. Either you open yourself to ambiguous results (and lawsuits), fraud (and lawsuits), or the demonstration will need to be 100pts on a scale where 10pts is enough to have already convinced people with real money. The prize becomes pointless, either being soft and therefore ambiguous, or only being claimable when it no longer matters. It seems to be a Catch-22 situation.
To use an analogy: It's like proposing the Orteig Prize (Atlantic crossing) as the level of demonstration necessary to "prove" the claims of the Wright Bros. By the time anyone is able to claim the prize, the basic claim "powered flight is real" is long, long proven beyond a shadow of a doubt; and probably already in commercial use. So what is the point of the prize?
Or another analogy: It's like the original X-Prize (flight to 100km) was offered before chemical-rockets were proven to exist. By the time someone could meet the terms of the prize, the idea of rockets will have been long since proven to everyone's satisfaction. The prize doesn't actually add anything. -
#47 by bad_astra on 14 May, 2015 16:06
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Has anyone looked into the problem of having cubesats splatting s-band noise too and fro on parts of the spectrum that are already allocated?
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#48 by bad_astra on 15 May, 2015 14:56
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Yes, as these will be focused essentially out of a horn antenna.
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#49 by bad_astra on 15 May, 2015 16:06
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thank you
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#50 by Impaler on 15 May, 2015 19:06
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I also believe that a cubesat is the best way to go for an X-prize. Prove constant mass and constant thrust of at least x.xxx N over minimum t length of time (starting from LEO). Thrust benchmark would have to be an order of magnitude above known effects such as the best-case photon rocket. Time and trajectory goals should be selected to indirectly and conclusively rule out all other known propellantless thrusting techniques.
This is silly, the prize granting body will simply inspect the vehicle before it is launched to verify it is a legitimate design. Submitting something to inspection is a normal part of wining a prize because their are always rules which need to be followed to be eligible. Do you think the first X-Prize was won without anyone getting to look inside Space Ship One?
No specific thrust level or period of times is a guarantee that the vehicle is propellent-less and having a high thrust requirement needless raises the bar for the performance of the system when we just want to get a irrefutable demonstration of ANY performance at all.
I would simply go with a target Delta-V, such as reaching Earth escape velocity, it is easily verified via telemetry and independently confirmed by radar. It establishes the drive as a viable means to raise satellites to GSO which is a immensely practical and immediate commercial usage. -
#51 by Rodal on 15 May, 2015 19:19
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The just announced successful Photonic Laser Thruster experiment by NASA which accelerated a 450 gram (~1 lb., ~4.4 Newtons) spacecraft simulator:
http://www.spaceref.com/news/viewpr.html?pid=45847
is an example of competing propellant-less means of space propulsion that should be taken into account in formulating this X-Prize as a propellant-less prize in general. Would the Photonic Laser Thruster, for example, be able to compete for the X-Prize ? (if so, the Photonic Laser Thruster is already ahead of the EM Drive in highest achieved thrust).
It seems (*) that the X-Prize needs to state not just a propellant-less means of space propulsion, but in addition that the propulsion has to be effected entirely by internal power and fields, without the need of any external forces or power from external fields (thus eliminating solar sails, electrodynamic tethers, propulsion using external magnetic fields, Photonic Laser Thrusters, etc.)
_________
(*) Assuming that the purpose is to reward the achievement of a milestone involving space propulsion without internal supply of propellant and without the action of external force fields or power, something that appears impossible perhaps with the exception of a photonic rocket (which does emit photons, and is entirely classical: as it does not break the law of conservation of momentum, and whose thrust/InputPower is several orders of magnitude less that what is claimed by EM Drive experimenters )
The concept of the EM Drive (if the EM Drive is ever possible) is self-contained while the Photonic Thruster is limited to the distance to the Resource Vehicle at the present time,Quote from: http://www.spaceref.com/news/viewpr.html?pid=45847I can see future development that includes optical cavities that span many kilometers achieved with precise mirror alignment to enable maneuvering spacecraft many kilometers apart, and propellant-free propulsion of satellites in formations.
Although Bae has written about the concept being used for Interstellar Travel:
http://ykbcorp.com/downloads/Bae_photon_propulsion_STAIF2_Paper_Circulation.pdf
using an "Interstellar Photonic Railway" -
#52 by A_M_Swallow on 15 May, 2015 20:01
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{snip}
It seems (*) that the X-Prize needs to state not just a propellant-less means of space propulsion, but in addition that the propulsion has to be effected entirely by internal power and fields, without the need of any external forces or power from external fields (thus eliminating solar sails, electromagnetic tethers, Photonic Laser Thrusters, etc.)
A practical thruster will take its power from solar arrays because batteries will not carry sufficient power to last the trip. -
#53 by Rodal on 15 May, 2015 20:04
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...
The feasibility of the EM Drive is a big IF, but for argument's sake, the EM Drive researchers have proposed internal nuclear power to supply the power, as it appears that the power from solar arrays will not supply enough power to enable human-crewed missions :
A practical thruster will take its power from solar arrays because batteries will not carry sufficient power to last the trip.
http://www.nasaspaceflight.com/2015/04/evaluating-nasas-futuristic-em-drive/ -
#54 by jordan.greenhall on 16 May, 2015 00:52
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The just announced successful Photonic Laser Thruster experiment by NASA which accelerated a 450 gram (~1 lb., ~4.4 Newtons) spacecraft simulator:
http://www.spaceref.com/news/viewpr.html?pid=45847
is an example of competing propellant-less means of space propulsion that should be taken into account in formulating this X-Prize as a propellant-less prize in general. Would the Photonic Laser Thruster, for example, be able to compete for the X-Prize ? (if so, the Photonic Laser Thruster is already ahead of the EM Drive in highest achieved thrust).
This is an *excellent* point.
As Dr. Rodal points out, there are other effective ways to generate various forms of thrust for specific applications.
What prevents those being of interest to an X-Prize is that they all are part of reasonably well understood physics and have been the subject of engineering consideration for a long time. They live well along the technology improvement s-curve and, consequently, are "relatively" unlikely to deliver a breakthrough in capability.
By contrast, if the EM Drive is real at all, this represents a major anomaly and novelty. Precisely because it is highly novel, it represents at least a *potential* breakthrough. To put it bluntly, we don't really have any idea what the upside could be. It could be quite significant (i.e., satellite applications are the low end of the potential). And this is what makes it interesting for an X-Prize.
Accordingly, the challenge design should rule out approaches that deliver "propellant free" thrust via well understood physics. -
#55 by Rodal on 16 May, 2015 01:30
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The just announced successful Photonic Laser Thruster experiment by NASA which accelerated a 450 gram (~1 lb., ~4.4 Newtons) spacecraft simulator:
http://www.spaceref.com/news/viewpr.html?pid=45847
is an example of competing propellant-less means of space propulsion that should be taken into account in formulating this X-Prize as a propellant-less prize in general. Would the Photonic Laser Thruster, for example, be able to compete for the X-Prize ? (if so, the Photonic Laser Thruster is already ahead of the EM Drive in highest achieved thrust).
This is an *excellent* point.
As Dr. Rodal points out, there are other effective ways to generate various forms of thrust for specific applications.
What prevents those being of interest to an X-Prize is that they all are part of reasonably well understood physics and have been the subject of engineering consideration for a long time. They live well along the technology improvement s-curve and, consequently, are "relatively" unlikely to deliver a breakthrough in capability.
By contrast, if the EM Drive is real at all, this represents a major anomaly and novelty. Precisely because it is highly novel, it represents at least a *potential* breakthrough. To put it bluntly, we don't really have any idea what the upside could be. It could be quite significant (i.e., satellite applications are the low end of the potential). And this is what makes it interesting for an X-Prize.
Accordingly, the challenge design should rule out approaches that deliver "propellant free" thrust via well understood physics.
I propose to use this wording
<<A space propulsion engine that can accelerate a spacecraft/satellite (*), in a controlled manner, purely by internal (to the spacecraft/satellite) generated power, without ejecting any particles from the spacecraft/satellite to achieve such acceleration, and without using any external forces or fields to achieve said controlled acceleration. (Thus, any space propulsion devices that eject propellant, and/or use any external forces or external fields (e.g. solar sails, electrodynamic tethers, propulsion using external magnetic fields, Photonic Laser Thrusters, etc.) are eliminated from consideration) >>
____________________
(*) the control, magnitude, (linear and rotational) direction, and duration of the acceleration as well as the total mass, orientation and location of the spacecraft to be specified
NOTES:
1) I am aware that to achieve significant controlled acceleration of a spacecraft/satellite, per the wording specified above, appears to be impossible (**), certainly according to classical physics, as it runs explicitly against the (universally confirmed) law of conservation of momentum, but this is just what the EM Drive researchers in the US, UK and China claim. As such it differs from previous X-Prizes, that just involved an engineering feat. Achieving the above would imply not just an engineering breakthrough but a break with the laws of classical physics.
2) The above wording does not include the words EM Drive or any particular concept or engineering device. The above-specified objectives can be satisfied by several presently proposed and tested, different, means of propulsion, such as:
a) the EM Drive: a closed resonant microwave cavity (experiments by NASA's Dr. White and Cannae's G. Fetta in the US, R.Shawyer in the UK and Prof. Yang in China)
b) the Woodward-Mach-Effect MET or MLT devices (Prof. Woodward and Prof. Fearn, California State University, Fullerton ) http://en.wikipedia.org/wiki/James_F._Woodward
http://en.wikipedia.org/wiki/Woodward_effect
3) The word acceleration was chosen on purpose instead of force. A specified change in velocity (over a specified length of time) is also suitable wording. Force is not suitable wording because force is an intuitive concept that is never directly measured, it involves additional quantities: what one directly measures in experiments are displacements (a force obtained by multiplying the displacement by a stiffness) or accelerations (a force obtained by multiplying the acceleration by a mass), or a piezoelectric effect, etc. Acceleration is an explicit, fundamental concept which involves primary dimensions of spatial geometry and time and that can be formally defined.
4) If the above wording is modified to allow ejecting particles, or to allow external fields to accelerate the spacecraft, it would be practically impossible to set a goal for the X-Prize in the spirit proposed by Jordan Greenhall, as for example, there are already a number of propellant-less devices that can accelerate a spacecraft/satellite by means of external fields.
(**) photonic rockets (e.g. using a military searchlight as a means of propulsion) are also excluded because they emit photons to achieve their propulsion. They are also practically excluded as their thrust/InputPower, even for a perfectly collimated beam, is several orders of magnitude less that what is claimed to have been presently measured by all EM Drive experimenters. -
#56 by A_M_Swallow on 16 May, 2015 02:35
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If the EM Drive emits tachyons then it does not meet this definition.
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#57 by Rodal on 16 May, 2015 02:37
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If the EM Drive emits tachyons then it does not meet this definition.
1) If the EM Drive emits any kind of particles it is not meeting the claims of any of the researchers in the US, UK and China. All the EM Drive researchers are claiming that there are no particles being emitted.
2) If the EM Drive would emit tachyons (a hypothetical, fictional, particle that has never been found in nature) then the EM Drive could be used for communication with the past, which would involve a time paradox.
(Tachyons are fictional particles that can travel faster than the speed of light. Sending signals faster than light, leads to to violations of causality. For example, somebody from the future could send Shawyer, using tachyons, a message with the design for an EM Drive for Shawyer to get the X-Prize
)
See: http://en.wikipedia.org/wiki/Tachyonic_antitelephone
Suppose A and B enter into the following agreement: A will send a message at three o'clock if and only if he does not receive one at one o'clock. B sends a message to reach A at one o'clock immediately on receiving one from A at three o'clock. Then the exchange of messages will take place if and only if it does not take place. This is a genuine paradox, a causal contradiction.
3) If for some reason, people still would like to widen the definition, "particles" can be substituted by "propellant" but I like "particles" because it puts all the researchers in the US, UK and China under a more stringent condition and because the size of particle that would qualify as "propellant" would have to be further specified (which would be kind of arbitrary). -
#58 by A_M_Swallow on 16 May, 2015 02:45
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If the EM Drive emits tachyons then it does not meet this definition.
If the EM Drive would emit tachyons (a hypothetical, fictional, particle that has never been found in nature) then the EM Drive could be used for communication with the past, which would involve a time paradox.
(Tachyons are fictional particles that can travel faster than the speed of light. Sending signals faster than light, leads to to violations of causality. For example, somebody from the future could send Shawyer, using tachyons, a message with the design for an EM Drive for Shawyer to get the X-Prize )
See: http://en.wikipedia.org/wiki/Tachyonic_antitelephone
We will deal with that problem when we see it. -
#59 by ChrisWilson68 on 16 May, 2015 03:58
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Why vacuum? Obviously it will be important for space operations that one be able to operate this thing in a vacuum - but for the purposes of proving that we have a "something new result," what does a vacuum add? If thrust is > X, don't all of the things that a vacuum would help eliminate already drop away?
Without a vacuum it becomes much harder to rule out other effects, even for higher X.c) Keeping in mind the above also don't worry too much about the X-prize and their association with risky endeavours. That is their raison d'etre. They know that this has a small chance of success and are delighted by the prospect. They are all about high risk / high reward innovation.
Yes, the X-Prize is meant to be associated with risky endeavours, but that doesn't mean all levels of risk are equivalent. The X-Prize loses its power if they start announcing X-Prizes for discovering unicorns, the Tooth Fairy, and Santa. I know in your world view unicorns aren't equivalent to the EM Drive actually working, but you have to understand that to the majority of well-educated people in technical fields the EM Drive working is pretty much equivalent to finding a living unicorn.
So by trying help the EM Drive you lessen the X-Prize's effectiveness for all those other X-Prizes for things like flying to the moon that are not inconsistent with known physics.
)