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Giving CubeSats Electric Propulsion
eldavojohn writes "Thirteen picosatellites were launched back in June of 2006 with the price coming down dramatically in the years since. But the Rubik's cube sized devices have no mobility, meaning once they're put in orbit, they stay in that orbit. The big problem is that traditional chemical propulsion systems are too large for ten-centimeter sided cubes weighing a kilogram. A new electric propulsion system designed by Paulo Lozano of MIT might change that. "
"The article explains how it works: 'Lozano's design relies on electrospraying, a physics process that uses electricity to extract positive and negative ions from a liquid salt that is created in a laboratory and serves as the system's propellant. The liquid contains no solvent, such as water, and can be charged electrically with no heat involved. Whereas other electric propulsion systems charge the ions in a chamber on the satellite, the ionic liquid in Lozano's design has already been charged on the ground, which is why his system doesn't need a chamber. Electricity is then converted from the main power source of the CubeSat, typically batteries or a solar panel, and applied to a tiny structure roughly the size of a postage stamp. This thin panel is made of about 1,000 porous metal structures that resemble needles and have several grams of the ionic liquid on them. By applying voltage to the needles, an electric field is created that extracts the ions from the liquid, accelerates them at very high speeds and forces them to fly away. This process creates an ionic force strong enough to produce thrust.'"
CubeSats are the "cheap access to space" needed for research and technology risk reduction that's been needed since the dawn of the space age.. and it didn't require some magical new propulsion method or even new economies of scale in launchers, just good standards and a very big customer, the Airforce academy.
For those of you who find the article a little light on details, here's the scientific paper:
http://sgc.engin.umich.edu/erps/IEPC_2007/PAPERS/IEPC-2007-145.pdf
This preliminary work is now being flight tested.. and, if all goes well, it'll soon be commercially available. When's soon? 3 to 5 years. That's what CubeSats give you, a reduction in lab-to-market from 10 years or longer to 6.
How we know is more important than what we know.
What, we've exhausted the marketability of the buzzword nano and have stepped it up to pico? Somehow I doubt that regular satellites mass 10^12 kilograms.
The engines on the the DNEPR-1 launched on 26 July 2006 shut down 86 seconds into the flight. It crashed approximately 25 km downrange. So, quite a bit of "bang" for your buck.
No folly is more costly than the folly of intolerant idealism. - Winston Churchill
just out of curiosity these satelites dont operate in deepspace.
Why not make use of earth's magnetic field to manouvre a bit around, maybe in combination with a small solar sail.
The point it that it wouldnt cost any propelant. (it might be less easy, but it will be able to move).
more might be done with a set of gyroscopes, they can move in areas in places where the gravitational field is curved. :) you can always improve jut by using your mind....
Around earth it is curved, some other scientist ( not crank.dot ) have allready shown how to do that.
I'm sorry i cannt find back a link of it but it has been explored this subject and it seams valid for earth's near space.
And earth's near space is the most likely place where these devices will operate.
What about having Packing Ratio Sats that are designed to stuff as many sats as possible into the payload faring of a rocket? Are cubes the best for cylindrical rockets?
Lozano's design relies on electrospraying, a physics process...
No way! I thought it would be a magic fairy magic process! (So magic, they used the word twice!) With glitter and unicorns!
</sarcasm>
Any sufficiently advanced intelligence is indistinguishable from stupidity.
Sounds like a variant of an ion drive, which have been around since the 50's.
Engage the Ion Thrusters, No. 1.
While MIT is without a doubt a fantastic school, I can't help but be annoyed by the summary's phrasing here. Electrospray has been around a long time. Electrospray propulsion research as well. I myself have worked on similar devices. What he has done is make a nice compact package which offers a unique solution to a unique problem, but using more or less already existing technology. Not giving proper credit where it's due only serves to discourage everyone else slaving away in the field. Somebody tell me otherwise.
Each edge of a Rubik's cube is 5.7 cm long. The cubesats are 5.5 times as large.
You know what's funny about this, is we're going to end up with a situation where increases in the propulsion systems end up sending newer satellites past ones launched earlier before they complete their missions. We'll end up with a cloud of ever decreasing technological junk arriving at distant civilizations....
Ace
I remember in physics class theorizing a propulsion system for a space ship. I figured that the only way to get thrust would be to accelerate hydrogen to as fast as you can then zip it out the thrusters. You'd have low mass, but high velocity propulsion. It sounds like this guy figured out a way to do this in a compact form. If this seriously works, I'm excited because it will allow satellites all over the solar system for relatively cheap. Put a high imaging camera on your satellite and snap pictures from around the solar system! It is nice that even though NASA has a shoestring budget that space exploration can still make advances.
God spoke to me.
I am actually working with several of these in my time at Uni. They really are tiny and only occupy a very small percentage of space (still more than 99% of LEO is unoccupied). Plus one of my personal objectives for the mission we are carrying out for the Air Force is to have them de-orbit themselves once the mission is complete. All of a spacecraft of that size would burn up upon re-entry, except if there was any titanium involved, which would survive to the surface (special regulation exists to prevent accidents with stuff like that) But getting back to the propulsion, this sounds like an interesting idea, it sadly wouldn't fit in our mission, but I'm sure it would be a nice solution for other cubesats (provided its cheap) all those parts get expensive quick.
Sorry, had to say it. That CubeSats? BORG CUBES!
Buanzo Consulting - 15 Years of GNU/Linux experience, for you.
"It's ion power Captain."
Only the dead have seen the end of War. - Plato
I stopped reading after the 3rd or 4th time they explained what something as simple as an ion was. Hello MIT, you guys are eggheads, not the Discovery Channel.
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