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Mars Rover: Tumbleweed Models 92

An anonymous reader writes "A North Carolina State project has prototyped a wind-blown Mars exploration rover. It draws its inspiration from the lowly tumbleweed, to cover large distances with low-power requirements. For collecting atmospheric, thermal or geological samples across great distances, the 'single-wheel' tumbleweed has some advantages over the usual four-wheeling approach to tough terrain."
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Mars Rover: Tumbleweed Models

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  • How do they steer? (Score:5, Interesting)

    by aarondyck ( 415387 ) <aaron@ufie . o rg> on Saturday May 24, 2003 @04:17AM (#6029887) Homepage Journal
    I quickly read over the article, and I failed to see any reference to direction of this thing. Now, it would seem to me that it could get blown into a place that it could not get out of. Without some sort of steering mechanism how do they ever plan to work this thing? And of course, since there are no GPS satellites around Mars they couldn't even determine the location, especially if it was picked up by the wind or something. It sounds like a good idea in theory, but it seems to me that the data would be nearly irellivent without positional data to accompany it.
    • Add a optical mouse (Score:5, Interesting)

      by zakezuke ( 229119 ) on Saturday May 24, 2003 @04:34AM (#6029922)
      Optical mouse technology might be the key in atleast determining speed. Assuming there is enough in the way of magnetics on mars, atleast some means of determining direction, in conjuction with an altermeter to determine it's relative height based on known factors. And provided you did some form of arial recon to verify it's position in reality at any given time, the location of such a device can be determined on a planet and (just about) any given time, assuming you have adquate maps to begin with.

      Steering, or some form of manual control to actually get this device into or out of a specific location seems somewhat vague to me... but one *could* do it with gyros.

      Seems like a great means of getting a land scanner about, provided you happy with where the wind takes you.
      • by lommer ( 566164 )
        Would it maybe be possible to place a limited GPS system on mars? I imagine deploying just three sattlites in geosynchronous orbit over the area where the tumbleweed probe is to land. Or, as alternative, deploy the sattelites in another orbit and settle for just collecting data periodically when the trio of sattelites are overhead. This second mechanism would have the advantage that it would still work if the tumbleweed traveled further than initially expected.
        • Re:GPS (Score:2, Interesting)

          by cellocgw ( 617879 )
          Would it maybe be possible to place a limited GPS system on mars? I imagine deploying just three sattlites in geosynchronous orbit over the area where the tumbleweed probe is to land.

          Question: how difficult is it to put satellites into geosynchronous (or Areosynchronous :-) ) orbit from outer space? Two problems come to mind: 1) we are good at shooting satellites up and nudging them into the right orbit, but I suspect there's a bit of a reverse-thrust required to get a satellite to "drop down" into or

          • I imagine it's most possible. When I was a kid, there was a system of radio positioning I used on ship, pretty much was installed for the first time. Pretty much just used two broadcast towers to peform simple triangulation. I want to say it was called Lomar, but I honestly can't remember, but nightly I would use a sextant and verify it with the device what ever it happened to be called. The device was only a few min off of what I gathered with my sextant, more then accurate enough to make establish whe
    • by Timesprout ( 579035 ) on Saturday May 24, 2003 @04:35AM (#6029929)
      I dont think steering is an issue with this sort of project. Its simply to collect data from as many wide ranging sources as possible for trend analysis at a later point as opposed to the majority of past/current efforts which can only focus on a few square metres of the planets surface. I imagine they dont really care where it goes if it broadens the sample pool.
    • by porksodas ( 515690 ) on Saturday May 24, 2003 @04:36AM (#6029933)
      A possible explanation may be that they don't want to steer. A device this simple, and with these kinds of power requirements, may be deployed on a far larger scale than a single, expensive explorer-cart. They might not be able to provide positional data, but that may well be compensated by their range and numbers. Imagine hundred of these rolling around Mars, for a year or so, continually transmitting usefull measurements... Besides : they might be able to detect their positions from down here - most likely not as accurate as GPS, but still...
      • by malia8888 ( 646496 ) on Saturday May 24, 2003 @06:01AM (#6030083)
        I don't know how they steer; however, from years of living on the plains of Oklahoma observing hundreds of tumbleweeds I know where the Mars rover will end up....

        stuck in a barbed wire fence;)

      • Imagine hundred of these rolling around Mars, for a year or so, continually transmitting usefull measurements...

        This is the whole point. We have become pretty familiar with the Earth over the centuries. We have a good idea of what to expect in any given geographical area. If I say "Brazil" you think of Amazon rain forests. "North Africa" conjures up images of sand and deserts. We don't have that kind of information about Mars.

        Sending out hundreds of cheap rovers will give us a quick and dirty overview of

      • they might be able to detect their positions from down here

        Or better: from Mars orbit. At a suitable point the main probe could eject the pods into a trajectory that would lead them to the surface, but itself continue on a course that would end up in orbit around Mars. From there pick up, position, and relay signals from the tumblers.
    • by fname ( 199759 )
      Well, this one doesn't steer; the article says it's just a protoype, to figure out how these thing will move on the surface. No need to instrument this kind of prototype.

      And they'll figure out positional data, probably not in real time. I imagine once they design (if they design) a real martian tumbleweed, it will have gyros and accelerometers to determine velocity, it will use time of day to determine it's position relative to the sun, at night it can check the stars. Every chance it gets, it will probabl
    • Yeah, like what if Mars has a great big hole, like Mel's Hole [melshole.com]?
  • by Anonymous Coward
    Mars doesn't have much of an atmosphere. It's very thin and in places, it's too cold and what would be an atmosphere is, instead, frozen. Such a thing would have to be very light and might not even work anyways. I understand the problems with a traditional four-wheeled exploration vehicle, but this does little to solve the problems. Also, it only allows for exploration where the wind takes it, not where scientists want it to go. Again, it's a nice idea, but it has a few problems that make it a bad idea.
  • Control? (Score:5, Interesting)

    by neksys ( 87486 ) <grphillips AT gmail DOT com> on Saturday May 24, 2003 @04:31AM (#6029915)
    This is an interesting idea.... but its entire basis for movement -- the wind on Mars -- seems to limit its usefulness to gathering data only on the areas of Mars where winds blow the strongest. Not that there isn't valuable information to be gathered there, but aren't windy areas somewhat of a scientific dead-end? I mean, if this thing ends up following the prevalent wind currents, wouldn't it just sort of follow a relatively smooth path worn away by centuries of wind erosion? The "juicy bits" of Mars are those that have been left more or less untouched for millenia -- those are the areas that give us the greatest insight into the history of the planet... which are precisely the areas that this thing won't be blown to -- and I suspect, where one would find just the sort of rough terrain this probe is built for. Wind has a bad habit of mixing things up -- ie. are these mineral samples native to the area, or have they been carried from the other side of the planet by this wind system?
    • I would guess that as part of a systematic approach it would work: you target some fixed or limited mobility probes at areas you are interested in and let other blow around where they will. If they are cheap you could get limited data about a wide area, rather than a lot of info about a very small location.

      Besides, there stands a chance that interesting things may be blown to the same places as the probes. Don't forget that the Earth was explored by wind power in the days of sail.

      Plus you can get data o

    • Re:Control? (Score:2, Interesting)

      by SharpFang ( 651121 )
      Add some small steering devices that will allow to deflect it by 5% from the wind route, and with average Martian hurricane at about 200km/h you can get it anywhere you desire even in relatively way weaker winds.

      Anchoring it at some interesting place is quite a different matter though.
    • This is an interesting idea.... but its entire basis for movement -- the wind on Mars -- seems to limit its usefulness to gathering data only on the areas of Mars where winds blow the strongest.

      Mars has worldwide sandstorms. Also, we don't suffer from an excess of data about "windy parts" of Mars. We've carefully analyzed about the same surface area as a couple of teepees would occupy. At this point, anywhere is fine.

      I agree that Imperial probe droids would be more precise, but I don't think the Wa

  • Ok (Score:3, Interesting)

    by Omkar ( 618823 ) on Saturday May 24, 2003 @04:34AM (#6029923) Homepage Journal
    This thing can move around easily and efficiently - fine. But how are we supposed to make it go where we want to go? On Mars, with its sandstorms, etc, control would probably be vital. OTOH, these could be deployed en masse and just keep beaming data back - durable, mobile, sensors.
    • Dont need controls (Score:3, Insightful)

      by DigiShaman ( 671371 )
      Seriously, you don't need to control it. After all, you would get much more data if this thing would last for years being blown in random locations then say....the rover having limited access next to base an only lasting for a short period of time. In the end, it amounts to data and cost effectiveness of getting it. I'm all for this concept.
      • That's how I see it. It's like, you know when you're on a level with Kakaru, and you cast either Mind Control or Parasite on all of them you can find? And then they fly around and scout out the map for you and you can just pay attention to the choke points without having to build a bunch of Observers or whatever? Seems to work pretty well.
    • Re:Ok (Score:4, Funny)

      by Timesprout ( 579035 ) on Saturday May 24, 2003 @05:38AM (#6030046)
      The plan is to fool the Martians into thinking they are beach balls so they take them home and thus provide lots of useful information.
  • by westyvw ( 653833 ) on Saturday May 24, 2003 @04:35AM (#6029927)
    By knowing the landing location, you can extrapolate where you have gone if you have am original bearing and known travel direction.

    A link about things like this:

    http://www.nasatech.com/Briefs/Nov01/NPO21235.ht ml

    Also you could remote view it if a non landing craft kept track of it

    On the other note, the winds are lacking on mars:
    Perhaps a solar wind collector?

    http://science.nasa.gov/headlines/y2001/ast31jan _1 .htm
  • Not such a bad idea (Score:5, Interesting)

    by reezle ( 239894 ) on Saturday May 24, 2003 @04:36AM (#6029934) Homepage
    If you could put 50 of these things down at once, scatter them around.... (They are terribly light-weight, right? Supposed to be blown around by the thin martian wind?) You sprinkle them on mars from orbit, and they expand to catch the wind for re-entry. They bounce a few times, then start tumbling along.

    So what if a few get stuck in a crevasse here and there? As far as location tracking, I'd assume they would each have their own radio frequency, and the orbiter would only be able to pick them up when it was over the horizon. Shouldn't be too terribly hard to get a rouch idea where the thing is. (Data sent back from the probe, compared against current mapping images ought to tell the rest of the story)

    I like this idea better than building one (or two) big clunky rovers that have a 50/50 chance of surviving Nasa's re-entry math.
    • I don't know... (Score:5, Interesting)

      by neksys ( 87486 ) <grphillips AT gmail DOT com> on Saturday May 24, 2003 @04:42AM (#6029947)
      That kind of makes me nervous. I don't really like the idea of any sort of "seed" probing like that. For one, it seems like an invasion of sorts. Two, its a recipe for spreading bacteria all over the planet -- despite NASA's stringent cleanliness, the fact of the matter is that some bacteria CAN survive space flight and reentry -- if that happens, and 20 years after we send these things to fly willy-nilly around Mars, how can we tell if these bacteria or whatever are originally from Mars or from Earth? It just seems a wee bit risky to me. *shrug*
      • For one, it seems like an invasion of sorts.

        Who knows what the Martians might get up to if they took this the wrong way...

        Remember those other Martian probes that just disappeared? Uh-huh, that was them...

      • by moncyb ( 456490 ) on Saturday May 24, 2003 @05:12AM (#6030007) Journal

        I don't really like the idea of any sort of "seed" probing like that. For one, it seems like an invasion of sorts.

        Well, if the Martians were really afraid of an Earthling invasion, they'd already have sent their nukes over here, now wouldn't they. ;-)

        Two, its a recipe for spreading bacteria all over the planet ... how can we tell if these bacteria or whatever are originally from Mars or from Earth?

        You call it contamination. I call it terraforming. ;-)

      • by Anonymous Coward
        if bacteria can survive in space then it would already be there. the earth is already "contaminating" the solar system with spores. What, you think a bacteria spore is actauly stuck in our gravity well? No. stuff is leaveing our planet all the time. Now I don't know if it would grow on mars or any where else....that has yet to be discovered.

        So please take you psuedo space enviornmentalism and shove it where the sun don't shine.
      • Re:I don't know... (Score:4, Interesting)

        by Davak ( 526912 ) on Saturday May 24, 2003 @07:22AM (#6030209) Homepage
        Sadly... we have probably already seeded Mars with bacteria.

        Links here [astrobio.net] and here. [innovationsreport.de]

        Luckily, unique bacteria trapped on Mars should have far different DNA that our earth-created bugs.

        Davak

        • Re:I don't know... (Score:3, Interesting)

          by Rick.C ( 626083 )
          Luckily, unique bacteria trapped on Mars should have far different DNA that our earth-created bugs.

          Ah, but that's if you assume that they evolved independently. One should never assume.

          One of my major questions is "If there are bacteria on Mars, are they related to those on Earth?" By contaminating Mars, we make that question impossible to answer.
      • by jc42 ( 318812 ) on Saturday May 24, 2003 @11:41AM (#6030804) Homepage Journal
        I don't really like the idea of any sort of "seed" probing like that

        Too late; it's been going on for a couple of billion years already.

        In the 1960's (and probably earlier) a number of astronomers did detailed studies of the Earth's dust tail, which is formed by the solar wind blowing off the outermost atmosphere. It's pretty thin, but it's thick enough that it interferes with some sorts of astronomy.

        They basically reported that the Earth's tail does contain particles of dust up to the size of bacterial spores. Tests had already shown that many bacterial spores can survive for long periods in space, the conclusion was obvious: The Earth has been spraying the outer solar system with bacterial spores for as long as bacteria have been making airborn spores, probably several billion years.

        So there is life on all the outer planets in the solar system, and it came from Earth. Whether any of those spores can survive elsewhere isn't known. But conditions on Mars are not all that dissimilar to conditions in the dry valleys in Antarctica, and some bacteria do survive and grow there. So it's possible that some of the bacteria from Earth are surviving and growing there, though probably not very well. OTOH, some have been there for a couple billion years, so there has been time for natural selection to do its thing.

        Some of the astronomers also pointed out back then that the Earth's dust tail doesn't stay within the solar system. It eventually reaches interstellar space. Considering that the Earth orbits the galaxy about 4 times per billion years, and bacteria have been here for around 4 billion years, the dust tail of Earth has pretty much permeated the galaxy with spores. Similar calculations would apply to any other Earth-like planet in the galaxy.

        This sort of calculation is part of the basic of the "panspermia" hypothesis that has gotten a bit of discussion in some circles. Of course, it's a bit difficult to collect real evidence on such a topic.
        But if we do find living bacteria on Mars or Titan that have chemistry similar to bacteria on Earth, it will be weak supportive evidence.

        This isn't the first time this topic has come up on /.

      • if that happens, and 20 years after we send these things to fly willy-nilly around Mars, how can we tell if these bacteria or whatever are originally from Mars or from Earth?

        By looking at their DNA?

        We can even tell if meteorites are Martian by examining the chemical constituents.
    • by ElGanzoLoco ( 642888 ) on Saturday May 24, 2003 @10:44AM (#6030649) Homepage
      ... big clunky rovers that have a 50/50 chance of surviving Nasa's re-entry math.

      You mean, like, math involving metric system and feet and inches?

  • by SegFault ( 547 ) on Saturday May 24, 2003 @04:50AM (#6029967)
    This kind of thing has been done since the 1960s at NASA's JPL. See http://www.jpl.nasa.gov/adv_tech/rovers/tmblweed.h tm

    SegFault
  • Off the wall (Score:2, Insightful)

    by Anonymous Coward
    This is smart, off-the-wall thinking.
    Exactly the kind of thing NASA needs these days.
  • by thynk ( 653762 ) <slashdot@th[ ].us ['ynk' in gap]> on Saturday May 24, 2003 @05:20AM (#6030019) Homepage Journal
    ...until it gets stuck in a fence or run over on the interstate.
  • Old Idea (Score:4, Informative)

    by Josuah ( 26407 ) on Saturday May 24, 2003 @06:40AM (#6030141) Homepage
    Kinda weird, but the article claims that "While working as a 2002 summer intern at NASA Langley, team leader David Minton initiated the idea to study a "Mars Tumbleweed" for the class project." Well, that'd be all great and everything if JPL hadn't already come up with the idea: Exploring Mars: Blowing in the Wind? [nasa.gov]. The JPL article is dated August 10, 2001.

    Someone probably should have told David Minton about Jack A. Jones' research at JPL. "Jack A. Jones...is leading JPL's research into various inflatable machines for exploring space. JPL's Inflatable Technology for Robotics Program aims to create rugged, all-terrain vehicles and other devices with low mass and low-packing volume."
  • by Anonymous Coward on Saturday May 24, 2003 @06:45AM (#6030152)
    Either these are geniune female geeks...

    or these guys have groupies!

    Picture here [dchoe.com] and here! [dchoe.com]

    Now I respect their project!

    AC
  • Once again, it seems that Mother Nature is providing us the inspiration for some design challenge.

    Consider the environment that a tumbleweed grows in: the desert - lots of open space, the ability to roam, and the need to traverse alot of ground with minimal energy. Sounds like Mars to me!

    And yes, this is all a cheap pop so you can check out my .sig.
    • I think there is a slight problem, because the Mars surface isn't really that flat like the deserts on earth. There are lots of cracks, mountains and just bottomless pits. Not that ideal a hunting ground for a probe that essentially can't be steered in any predictable way.
      So I imagine they would either have to choose the landing site very precisely (even if successful the rover probably wouldn't have much room to travel until it gets stuck somewhere) or the other approach might be to deploy not one but more
  • Is it me? (Score:5, Funny)

    by mikeophile ( 647318 ) on Saturday May 24, 2003 @07:24AM (#6030214)
    Or does it look like the guy in front on the main article picture is copping a serious feel from the hottie next to him with his right hand?

    She doesn't seem to mind.

    NASA girls rock.

    • Re:Is it me? (Score:3, Informative)

      by valisk ( 622262 )
      lol, thats just your filthy mind.

      But to pedanticaly correct you:

      North Carolina State University girls rock!

  • Mars has all those mile-deep canyons, along with about a billion other places a probe like this could wander into and never return. Wouldn't a weather balloon make more sense? I know the atmosphere is thin, but I still keep seeing designs for Martian gliders.

    Also, the story doesn't seem to indicate whether these things can steer themselves (though it would certainly be possible to do so), or how it reports the data back to NASA. I would assume that it reports back to an orbiting satellite. Having a
  • Donkey years ago, I read a book by Heinlein where one of the Martian creatures was modeled on a tumbleweed. Art inspires science again.
  • by Anonymous Coward
    A paper on this was presented last November by another student team from the Colorado School of Mines.
    Link to the paper: http://www.lpi.usra.edu/publications/reports/CB-11 52/colorado.pdf
  • So f*cking what? (Score:2, Informative)

    by Czernobog ( 588687 )
    Every University round the globe that has an even remotely competent Aeronautical/Mechanical/Electronics/CompSci/Vision department, takes part in a "Mars Rover" project, funded by xyz.
    So, what's so differne about these folks, that necessitates (correct spelling? I doubt it) front page status?

  • Tumbleweed Balloon (Score:3, Interesting)

    by Rick.C ( 626083 ) on Saturday May 24, 2003 @11:20AM (#6030737)
    This is sort of a hybrid idea - a cross between the tumbleweed and a weather balloon.

    Design the tumbleweed sphere with a helium bottle inside. Add a valve to vent the helium to the outside. If there has been no detected movement of the sphere for a day or two, inflate with helium until it attains slightly positive bouyancy. Drift off for a few hours and then open the vent, settling back to the ground. Let the wind blow it around in tumbleweed mode until it stops.

    Rinse.
    Repeat.
  • GO WOLFPACK!!! (Score:1, Offtopic)

    by sstory ( 538486 )
    --Steve (NCSU physics major)
  • I'll have you know there's nothing 'lowly' about the magnificent Tumbleweed!
  • There are a lot of comments about the pros and cons of being limited to the wind-blown parts. To me, one important thing we could learn is the wind patterns on Mars. Both weather and climate are interesting, hard problems.

    In the same vein, a solar-powered glider would also be interesting (use fuel cell for power at night). However, the Martian atmosphere is so light that this would probably require a ridiculous wingspan.
  • NASA-Langley had a section of the "science" building at the State Fair in Richmond, VA last year, and invited both civil servants and contractors (like me) to help man it. One of the displays, which I was at, was a large aquarium tank with a fan attached to one end, and little rocks and sand and junk cemented to the bottom to simulate the Martian landscape. I had six different models of potential "tumbleweed" craft, designed by schoolchildren, that you would drop into the tank and see how well it tumbled. T
  • Take it from someone who lives in t'weed country.

    They roll and roll and roll...until they hit something. Then they sit until they rot.

    And if you're dropping them where they can't possibly hit anything, then why make them ambulatory? The climate won't change until the terrain does.
    • It would be easier for a tumbleweed to stop rolling on Mars with its thin atmosphere and softer sand dunes (lower gravity, no rain, no plants) than on Tellus.

      This seems way to risky. NASA can't afford any more blunders, and if by chance the ball should happen to roll a few meters and come to a stop, it might be the final fiasco needed to kill the planetary space program.

      What NASA needs to show to get increased funding is spectacular breakthroughs. This isn't it.
      This would be just another yawn in the pre
  • ... I would be far more interested in "exploring the surface" of those three babes in the photo. THEY are engineering students!?!?!
  • For collecting atmospheric, thermal or geological samples across great distances, the 'single-wheel' tumbleweed has some advantages over the usual four-wheeling approach to tough terrain.

    Until it runs into a rock or low spot and gets stuck.
  • Good Project (Score:2, Informative)

    by bumblingbee ( 674152 )
    I just graduated from NCSU's aero department ( www.mae.ncsu.edu [ncsu.edu]) with these guys- I did the aeronautical design project, but the Tumbleweed project turned out alot better than I expected. From what I heard, the guys at NASA were much more enthusiastic and receptive to their design than previous years' projects (a mars balloon, among others).

    As far as steering, several options I remember hearing their team members discuss throughout the year were actuating the planar sails on the inside of the carbon fi

  • Evolution. I see this "Tumbleweed Earth Demonstrator" as a one-cell precursor to Theo Jansen's Strandbeests [strandbeest.com]. This critters literally walked using nothing but wind power [popsci.com].
  • The atmospheric pressure on Mars [washington.edu] is only 7-10 millibars. (Earth is about 1000 millibars.)

    Despite telescope pictures of "Martian windstorms", Pathfinder's wind sock [nasa.gov] didn't move much. Those "windstorms" are drifting clouds of very fine dust, more like air pollution than sandstorms.

    Wind-powered travel on Mars doesn't look promising.

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