Want to read Slashdot from your mobile device? Point it at m.slashdot.org and keep reading!


Forgot your password?
Space NASA

Sophisticated Balloons Could Help Steer Spacecraft 96

coondoggie writes "Getting spacecraft traveling at hypersonic speeds to slow down and land or achieve a particular orbit on a dime is no easy feat. But researchers are developing a tool that will let engineers model and ultimately build advanced flight control systems that meld balloon and parachute technologies known as a ballute (BALLoon-parachUTE). Basically a ballute is a large, inflatable device that takes advantage of atmospheric drag to decelerate and capture a spacecraft into orbit around a planet, according to NASA who is funding Global Aerospace to build such a tool."
This discussion has been archived. No new comments can be posted.

Sophisticated Balloons Could Help Steer Spacecraft

Comments Filter:
  • This would be a very efficient way to put a satellite into a nice, 100 mile high orbit. DOH! 100 kilometers! WHATEVER!
  • by K. S. Kyosuke ( 729550 ) on Thursday April 16, 2009 @11:37AM (#27598445)
    I just hope that the life of NASA folks is not becoming obsessively balloonic.
  • by Anonymous Coward on Thursday April 16, 2009 @11:39AM (#27598475)
    The word (warning, link not for PETA or squeemish) balut [wikipedia.org] is pronounced baloot too.
  • Old tech? (Score:5, Interesting)

    by jamstar7 ( 694492 ) on Thursday April 16, 2009 @11:41AM (#27598495)
    OK, this idea's been around for awhile. Its major useage in Hollywood was in the movie 2010 [imdb.com] when the Russian spacecraft used one for aerobraking in Jupiter's atmosphere. Cute effect, but like Dr Floyd said, "Nice in theory, but the guys who did the numbers aren't here."
    • Also of note, the ballute was ahead of the spacecraft, instead of behind it. It should have been behind the spacecraft, the way it unfolded in front indicated a non rigid structure that should have been pushed back towards the spacecraft by the pressure of the atmosphere.

      • Re:Old tech? (Score:4, Insightful)

        by HTH NE1 ( 675604 ) on Thursday April 16, 2009 @01:04PM (#27599531)

        the way it unfolded in front indicated a non rigid structure that should have been pushed back towards the spacecraft by the pressure of the atmosphere.

        You neglect the internal pressure of the ballute which would be made greater than that of the outer layer of the atmosphere of Jupiter at that altitude, giving it rigidity.

        Someone should try putting a balloon held in a forward position by a solid structure (so it doesn't flutter backwards) against the wind in a wind tunnel to test this, post the video to YouTube, and provide a link here.

      • I was under the impression it was filled with ablative foam that kept it from collapsing.
    • Re:Old tech? (Score:5, Informative)

      by interiot ( 50685 ) on Thursday April 16, 2009 @12:21PM (#27598999) Homepage
      Yup, it was invented in 1958 [parachutehistory.com], and was used on the Gemini back-up ejection seat, and is used on the Mk-82 unguided gravity bomb.
    • Heck, they use it in zeta gundam to drop mobile suits on Earth in the Jaburo assault...and if Japanese animation has taught me anything, this is gonna work!

        It'll work only for named heroes and important villains, all the other astronauts are fucked.
      • Re:Old tech? (Score:4, Informative)

        by EdZ ( 755139 ) on Thursday April 16, 2009 @01:01PM (#27599489)
        Ballute assisted re-entry has been a staple of the Gundam franchise for quite a while, along with wave-rider [wikipedia.org] airfoils and O'Neill cylinder [wikipedia.org] colonies. Some of the science behind it is rather good, though somewhat offset by the idea that giant robots make everything work better.
        • The quality of science in Gundam has been a staple of the franchise for quite a while too :P. Some people balk at the idea of giant robots, but try and extrapolate the evolution of military armour for a moment. Right now we have slow tanks on treads. Good for rough terrain, bad if it gets too rough. Replace the tracks with four or six legs, and then it becomes a game of maneuverability, not firepower. People will start making anti-tank tanks to take out the new legged ones. Another cool thing about mo

          • by EdZ ( 755139 )
            Much as I love my giant robots, powered armours, landmates, VTs, and so on, it's really not that practical for a front-line war machine. Sure, increased mobility sounds good, but it's not that great a leap over tracks. Warfare at the moment is a game of range and sensors, with the actual weapons almost guaranteeing a kill (with the exception of OLD RPGs vs new MBTs). A modern tank can hit a helicopter with it's main gun, assuming said helicopter hasn't blown the tank to bits from a few miles away over a hil
        • by QuantumG ( 50515 ) *

          I'm a big ran of O'Neill, but I gotta wonder what exactly he was smoking when he suggested that we were capable of building them with 1970s technology. Island Three was to be two counter rotating cylinders, each 3km in radius and 30km long, as well as a 15km radius ring of spheres for farming. That's a hell of a lot of steel. Each cylinder is 566 sq km .. of undeclared thickness.

    • Look at the cover of Popular Science, October 1983. Note: I used to work with Dr. Dana Andrews, at Boeing, in the early 80's. We were working on such things back then. Dana was the consultant for the movie 2010. We had fun going to see the movie as a group, and making critiques:

      "Hey, that's a subsonic wake, that's wrong"

      Aerobraking is a subset of hypersonic aerodynamics. Inflatable things like Ballutes are zero lift pure drag devices. You can also control direction if you use a lifting body shape. if

  • MAGIC BALLOONS (Score:1, Interesting)

    by DJCacophony ( 832334 )
    Atmospheric drag? It sure is going to be cool when they come out with a big balloon, covered in multi-inch thick ceramic tiles for heat dispersion.
    • Re: (Score:3, Informative)

      by LandKurt ( 901298 )
      The smaller and denser an object is the worse the heat load is on re-entry. Using a ballute to increase the surface area means there is less need for high tech fragile ceramic tiles. Another way to look at it is that the greater area means there is more force to slow down the spacecraft before it gets into denser levels of the atmosphere.
    • Re: (Score:2, Funny)

      by Anonymous Coward

      Atmospheric drag? It sure is going to be cool when they come out with a big balloon, covered in multi-inch thick ceramic tiles for heat dispersion.

      You seem to know an awful lot about this. Are you some sort of Atmospheric drag queen?

    • Re:MAGIC BALLOONS (Score:4, Informative)

      by Nyeerrmm ( 940927 ) on Thursday April 16, 2009 @01:04PM (#27599521)

      This is being used for aerobraking and aerocapture, not entry/re-entry. The idea is that it flys through the upper reaches of the atmosphere to slow it down and send it into some kind of closed orbit about the target body. Not nearly as much of a heating issue, particularly if you're talking about Mars which has a much less dense atmosphere.

      No real reason to use it for re-entry since a Viking-style Mach-2 chute, or one of the new-fangled Mach-3 chutes will do the job already.

  • I seem to remember 2010 Space Odyssey using what they called in the movie a ballute to slow down on arrival at Jupiter.

    • by LWATCDR ( 28044 )

      The military as well. They use them to slow bombs dropped at low altitude.
      Now one at hypersonic speeds will be challenging.

      • by rlseaman ( 1420667 ) on Thursday April 16, 2009 @11:58AM (#27598723)

        "Now one at hypersonic speeds will be challenging."

        Depends strongly on the density of the atmosphere and the drogue's size. A ballute might even be designed to grow or shrink as the spacecraft slows and the atmosphere becomes more dense. The necessary scaling might be vastly different between Mars with a thin atmosphere and Venus with a very dense atmosphere. The temperature would also be an issue since the planets vary from cryogenic to hot enough to melt lead.

  • by Thanshin ( 1188877 ) on Thursday April 16, 2009 @11:43AM (#27598519)

    advanced flight control systems that meld balloon and parachute technologies known as a ballute (BALLoon-parachUTE).

    I'd have called it Paraloon.

    Or possibly Ballachute.

    "Ballachute! I choose you!"

    Yep. It works.

    • I find it somewhat disappointing that whoever wrote the summary felt the need to clarify where ballute came from after having said "meld balloon and parachute" only 4 words beforehand..

      • The first reply on the first comment was someone that didn't realize that "meld" is a word. So apparently it was necessary. Yes, this is sad.
  • by koterica ( 981373 ) on Thursday April 16, 2009 @11:45AM (#27598549) Journal
    North Korea is developing long range "Communications Darts". These are not in any way intended for use as weapons.
  • Your NASA Tau Chi name is...Ballute.
  • My Filipino heritage is screaming in agony of trying to eat something not fit to be eaten.
  • I thought that was that NASTY Filipino snack food consisting of a cooked, fertile duck egg with a pinch of salt...

  • by 192939495969798999 ( 58312 ) <info&devinmoore,com> on Thursday April 16, 2009 @12:04PM (#27598817) Homepage Journal

    My other car is a ballute.

    Oh yeah? well my new cadillac is a ballute de ville.

    yo momma's so fat, when she jumps out of an airplane, she has to use a ballute.

    I would write more, but my computer's about to crash, so I have to reballute.

  • by khallow ( 566160 ) on Thursday April 16, 2009 @12:27PM (#27599083)
    The key problem with atmospheric braking is heat dissipation. Craft in orbit have considerable energy (since they have orbital velocities of around 7.5 km/s or more) while craft returning from the Moon or Mars have far greater velocities (the Apollo capsules returning from the Moon had velocity of roughly 11 km/s, which is double the kinetic energy per kilogram of a low Earth orbit satellite). Entering orbit around a gas giant (like Neptune) will require even velocity dissipation. If you and everything on your spacecraft were indestructable, you could just dive straight in. In practice, since spacecraft aren't indestructible and payloads (eg, living humans) are somewhat fragile, you need to decelerate at a much more gradual pace. As it turns out, the sooner you can start deceleration, the better. The key way to decelerate early is to increase the cross-section area of the vehicle relative to its mass. This also has the advantage of distributing the heat load from atmospheric braking across a wider area and reduces the overall temperature of the vehicle. This reduces the complexity of the structures used to protect the vehicle from atmospheric heating (called "thermal protection systems" or TPS).

    Capsules like Soyuz or Apollo have the highest mass per cross-section area and hence have high heating loads and decelerations. The Shuttle has pretty high heating loads as well. If it had been made considerably "fluffier", it wouldn't need the special tiles for its TPS.

    Ballutes are cheap ways to greatly increase the cross-sectional area of the vehicle. For a fictional example of a ballute, the film 2010 portrays the Soviet spaceship, Leonov using one as it aerobrakes to slow down enough to orbit around Jupiter. Technically, in this case, it is aerocapture. This is aerobraking with only one pass through atmosphere. The usual process involves many passes through atmosphere, shedding some velocity on each pass.

    The innovation in this article is the ability to control a ballute which has some lift. There are two possible uses that I can think of, off the top of my head. First, it can be used to steer the vehicle so that more of its path is in the less dense high atmosphere. In other words, we can steer to some degree the trajectory so that we get better deceleration and heating loads. Second, aerocapture is very hard. The key problem is that any changes in the atmosphere will change the trajectory, possibly enough to make the attempt unsurvivable. Even if the vehicle isn't in danger, small differences in the atmosphere or the vehicle's reentry trajectory mean the vehicle may end up on a different trajectory. If it is landing, it may end up far away from the desired landing spot. Ability to steer reduces the uncertainty of aerocapture and provides some valuable margin of error for a spacecraft.
    • reduces the complexity of the structures used to protect the vehicle from atmospheric heating (called "thermal protection systems" or TPS)

      I'd like to see a report on this Thermal Protection System you speak of.

      Please make sure it includes the mandatory first page.

  • by SensitiveMale ( 155605 ) on Thursday April 16, 2009 @12:31PM (#27599151)

    steer my eyes straight to their racks.

  • In other news, Al Gore is starting a pre-emptive campaign against "Air Ballution". Pundits are already sharpening their witty one-liners.
  • This article is a real let-down (pun intended). When I saw the title in my RSS feed, I was expecting to read about some novel idea to use balloons to steer a craft in the vacuum of space. Using things like balloons and parachutes to slow things down in the atmosphere is not a novel idea.
  • filipinos laugh at the unintended linguistic joke

    balut [nbc.com]

    althoug, using the word for something that is half-duck half-egg, is a pretty good metaphor for this polymorphous device

  • Isn't this only useful if you want to orbit a planet with an atmosphere that won't destroy the ballute?
    And question #2, if you're in the planet's atmosphere you're no longer in orbit - right?

    There are tons of space nerds on /. so please feel free to jump in and clarify - I'd really like to understand.
  • Our favorite part of ballute aerobraking is when the beautiful Russian heroine comes into your state room & starts making love to you.

  • After a long conference and much discussion, it was decided not to use the other alternative, unsophisticated balloons.
  • Am I the only one who saw the title in an RSS feed and read it this way?

    Sophisticated Baboons Could Help Steer Spacecraft

  • The Russians did do this or will do this in 2010. It's called aero-braking. Just don't attempt any landings on Io.

  • "... spacecraft traveling at hypersonic speeds..."

    I'll bite, what is the speed of sound in the regions in which he ballutes will be used? Doesn't it depend on both pressure and temperature? Are the SiFi movies right and there is sound in space after all?

  • that Ballute is also the asian word for an egg with a dead fetus inside it (yes, to eat).

Q: How many IBM CPU's does it take to execute a job? A: Four; three to hold it down, and one to rip its head off.