Do you remember the electromagnetic or EM drive from the 20-teens (which was first conceptualized in 2001)? While most engines that seem to defy common laws of physics tend to fall away when measured carefully, the EM drive actually delivered thrust when thoroughly tested. Among the groups studying it, the Chinese Academy of Sciences built a model and verified that at an input power of 2.5kW, their EmDrive thruster provided 720mN of thrust. (720 milliNewtons isn't much thrust, about 2.5 ounces in the imperial system, but perhaps it could be further optimized).
Later tests showed that the engine wasn't doing any new kind of physics and
the idea faded away. The big selling idea was that it didn't use exhaust in an
action/reaction system like conventional engines.
The goal of the engine is, of course, to get rid of the requirement for fuel to expel. All rockets require that action/reaction momentum transfer to work, and eject something, whether hot gasses in the case of virtually every rocket you see, or atomic-sized particles in ion engines. Even the fusion engines that seem to be the grail a large sector is pushing toward need to bring massive amounts of hydrogen (deuterium or tritium) to fuse and eject.
The topic has come up again with the emergence of a new company called Exodus Technologies co-founded by Charles Buhler, who helped establish the Electrostatics and Surface Physics Laboratory at the Kennedy Space Center. The company claims to have found a way to manipulate electrostatic fields to produce an asymmetry - more force in a required direction. Not milliNewtons, like the EM drive, but more electrostatic repulsion than the weight of the engine. That is, more than the force of gravity. It can lift itself.
Image from a talk in which Dr. Buhler presented his findings at a recent Alternative Propulsion Energy Conference (APEC).
We could be talking about hours to the moon instead of days, or days to Mars
instead of months. That would totally revolutionize space travel. From the
Exodus Technologies website:
Like chemical rockets, Exodus propulsion devices create momentum for a spacecraft's motion. However, Exodus' platform uses the interaction of electrostatic fields to harness the momentum found in electricity rather than in a chemical reaction.
The process of generating the Exodus Effect(TM) is repeatable, predictable, published and well-understood. After being released from a 2-year national security hold, the first patent describing the Exodus Effect(TM) has finally been issued by the USPTO. Both acceleration and thrust (Newtons) are quantifiable and supported by 3rd-party validations. These facts are what separate Exodus from the pack.
The key breakthrough appears to be creating asymmetrical fields by using an asymmetrical array of capacitors and high voltage.
Of the couple of videos I watched on the subject this seemed best to me:
Similarly, of the couple of articles I used in preparing this piece, I think this one from the Debrief was the best.
The way I look at this, in light of the EM drive, is that this is the first
step, but as Richard Feynman once said, in science, “the first principle
is that you must not fool yourself, and you are the easiest person to fool.”
There needs to be lots of review of this. I don't know how, but the most likely case is they missed something and it's wrong. Is it possible there's an aspect to
electromagnetics that nobody has thought of or perhaps just never noticed
before? Absolutely. This is where the saying that science is self-correcting
comes from. Get more people looking at what they did, more groups building and
testing things and either verify it or show where it's wrong.
Also from the Debrief article, the summary to APEC.
The engines must interact with something to create thrust. Anti-gravitic drive? Wave function of some form of electro-magnetic radiation?
ReplyDeleteHas to interact with something.
There is no something-for-nothing in the real world.
Does this only work in a high gravity field? In an atmosphere? In a high gravity field in an atmosphere?
Be interesting if this resulted in the discovery/proof of some new particle called gravitons or something.
Pushing on something: electric fields are everywhere.
DeleteRemember from way back, Cavendish's work on discovering gravity as the equation we all know now, he did his work suspending steel balls and measuring the attraction perpendicular to the dominant gravity? The high school joke was how Cavendish's balls changed the world.
As I see the experiment, they're basically doing that; testing their apparatus in torsion. They can produce asymmetrical E fields and they say that has the effect of moving the center of mass. Can't say I understand it.
If you go to their webpage, you have to click on "Gallery" along the top of the page to see it, but they have two videos of them testing it perpendicular to gravity - hanging on a wire and rotating.
The thruster (effector) can lift itself, but what about the mass of the HV power supply required to generate the required fields?
ReplyDeleteIf it works do we still need chemical rockets to get up to orbit where these E-thrusters can take over?
I'm guessing nobody knows, yet. This is still very early in the development.
DeleteThat said, I'm guessing strong enough electric fields to overcome gravity and launch payloads to space, would arc over like lightning, and it would have to be for deep space.
One solution to the problem of powering the fields might be using lasers or microwaves to beam power to the vehicle from ground station(s).
DeleteBoth Dean Ing in his novel The Big Lifters and Jerry Pournelle in his High Justice series used beamed power, albeit in different ways.
Ground stations would work for the ascent to orbit, but I suspect that for deep space operations, either orbital power stations or small(10' cubes at most) reactors would be needed.
Fish don't swim and birds don't fly by expelling something.
ReplyDeleteLacking water, air, or phlogiston, electromagnetics may be the way to crack the code of finding something to push against in the vacuum.
Step One: Proof of Concept.
Step Two: Speed Limit?
You've seen that wheel where a "6" turns over to become a "9" on the other side? That's how it works. I'll believe it when the company comes to the press conference in a flying car. Double points if it's powered by fusing flat beer to banana peels.
ReplyDeleteI thought that previous 'microwaves in a cavity' engine turned out to be a motor interacting with Earth's magnetic field?
Hope is the most dangerous of all pernicious influences on science. It clouds, distorts, and deflects observation, and thus pollutes the gathering of objective data. Remember Fleischmann and Pons?
ReplyDeleteWhile I, too, hope there's a way around the need for mass ejection to propel a space vehicle, I'm not betting the rent money on it -- and among my hopes is that the researchers straining to verify this leave their hopes at home.
"Massless" propulsion has been around at least the Yagi-Uda antenna. RF is photons, and the photons have momentum. A Yagi (among many other antennas) "squirts" more photons in one direction than others, so there is a net momentum in that direction. The antenna thus gains the same momentum in the opposite direction. Thus, energy into thrust with no "matter" being ejected. But it won't get off the ground....
ReplyDeleteThat's pretty much how the EM drive worked, that started out the article, except it was at microwaves with a sort-of horn antenna. Generated some thrust, but 2-1/2 ounces thrust for 2-1/2 kW input.
DeleteEasy way to prove this. Just slap one of these EM drives to a small satellite and send it up on one of the SpaceX transporter missions. Then we'll see how it flys.
ReplyDeleteThe service calls for minor tweaks under that plan is cost-prohibitive.
DeleteThe bigger issue is physics. Amount of output for a given mass is always the problem.
So far, we haven't miniaturized nuclear power plants to the same degree we've done with computer chips over the same period of time.
And until we can do that, there'll never be any proof of concept.
That's a failure of engineering, however, not necessarily a failure of theory.
Kind of like dropping a complete DC-3 minus the engines would have been in 40 B.C., even if you'd given them an accompanying aeronautical manual. They still couldn't fly, no matter how many slaves manned the drive wheels.
Bear well in mind that in living memory, i.e. before 1951, a nuclear power plant was pure science fantasy hopeium too.
Well-put, Aesop.
DeleteSomething to bear in mind with this engine is that even as good as a demonstration as it is, it's still only around 50 grams of thrust.
It's a really good breakthrough, if it actually is working as they say and why they say, but there's a lot to do before it's ready to fly. IMO, of course.
50 grams of thrust for as long as you have power will add up, and if you have enough thrusters a telescope would be able to point as long as the solar panels held out.
DeleteMaybe its really stupid simple, buts its the technology thats hard, I'm saying what if you figure out a method for accelerating electrons, down a super conductor, lots of them, return them on a loop, but when they make the turn to go back to the accelerator, they slow a bit, and in this way you get two pulses of thrust that are not counteracting each-other, simple on principle but requires some new tech and materials, oh and you need a power source which cranks out serious amperage, or very high voltage, such as a dry fission reactor, maybe one of those thorium ones, or ideally fusion.
ReplyDeleteThere are 2 problems with physics today. Probably more than 2.
ReplyDeleteThe first is the publish-or-perish insanity. There has been a push in the last few years to get the garbage out of the "peer-reviewed publications." Lancet has been retracting articles, and dozens of magazines in various disciplines have been closed. This isn't just a physics problem. It's a science in general problem.
Aside from the garbage, the need to publish some result regularly means that the research goals are small, and expected. Plans for the Large Hadron Collider were being drawn up in the '80s when I was in college. No plans for the next generation are being drawn up because science isn't really ready to swing for the fences again.
On that same topic, the gravitational wave results achieved a few years back were decades in the making. The first LIGO-style detectors were built in the '60s or '70s. They were small scale, almost prototypes.
The lack of swinging for the fences means that the advances are not coming. Everyone from Einstein on, threw off the old conventions and started new. Today, no one dares throw off those conventions for fear they won't be published.
OK here's a 3rd problem. Politics.
DeletePeople think that science, especially physics is all about pure knowledge. They forget the politics.
Consider electromagnetic waves. In the 1800s the belief among scientists was that there had to be something for the waves to exist in. Sound waves were in air, electromagnetic waves HAD to be in something, what they called the aether.
The last experiment run to try to detect the aether was run in the 1950s, because even though so much had been done by that point it was still necessary to "prove its non-existence." Though how you can prove a negative is still a puzzle to me.
The current sacred cow, dark matter/dark energy, was invented out of whole cloth to "fix" a problem with gravity introduced by Hubble's results. Instead of saying "we don't understand how gravity works," we invented a term to keep all of our old equations happy, and introduce something for which there was no evidence at the time. The "evidence" uncovered since is a bit questionable. https://youtu.be/n33aurhg788
That's not the only problem, but it is a political sacred cow. The problems are starting to be tough to ignore, doesn't mean people won't ignore them