Tumbleweed Rover for Marathon Martian Journeys 177
An anonymous reader writes "A prototype Mars rover, the Tumbleweed, has completed its 40 mile trek across the Antarctic, driven only by winds even in rough terrain over eight days. While the current rovers are designed for flat, equatorial regions, the tumbleweed design is geared to cover longer distances across what many consider the more interesting and dangerous polar regions on Mars."
Spaceballs!?! (Score:5, Funny)
(dives for cover)
Re:Spaceballs!?! (Score:2, Funny)
(dives for cover)
Maybe they could put retired general Schwartzkopf in charge of the mission.
"Thank you for pressing the Self Destruct Button."
That's no tumbleweed! (Score:5, Insightful)
MOD PARENT UP (Score:1, Funny)
Rover (Score:5, Informative)
Rather scary creatures... Much more so then the orginal 'robot car'that Patrick had envisioned...
Re:Rover (Score:2)
Re:That's no tumbleweed! (Score:2, Informative)
http://www.retroweb.com/prisoner.html
Re:That's no tumbleweed! (Score:2)
Reactive Orange-alert Vigilant EnforceR
Does this mean... (Score:2)
Re:Does this mean... (Score:1)
Re:Does this mean... (Score:2, Insightful)
Re:Does this mean... (Score:2, Informative)
Re:Does this mean... (Score:2, Interesting)
Fortunately, it should be possible to do it with relatively few satellites. Just three, in fact, for a base system, if all are geosynchronous.
And the ball should have some means of getting itself out of a bowl. Maybe a high-RPM motor inside that runs off a large capacitor to give a sudden burst of torque.
Re:Does this mean... (Score:2, Interesting)
Re:Does this mean... (Score:2, Informative)
Re:Does this mean... (Score:2)
The reason one satelite should be enough is that I'm guesing you can just take distance measurements over a period of time. Thus, the one satelite can function as three, as long as you are willing to wait for the reading and can guestimate how you've travelled in the meantime.
Powered by? (Score:2, Insightful)
Re:Does this mean... (Score:5, Interesting)
--
For news, status, updates, scientific info, images, video, and more, check out:
(AXCH) 2004 Mars Exploration Rovers - News, Status, Technical Info, History [axonchisel.net].
Re:Does this mean... (Score:3, Interesting)
That is an exaggeration. The rovers can go at least about 100 feet a day, but often stop to look around or poke rocks. Look how far Spirit [nasa.gov] has gone. It's lander is little more than a spec in this scene. I bet Opportunity will go even further per day when it moves out of the crater because there are less rocks in the way to study or stump the rover.
Re:Does this mean... (Score:5, Interesting)
What do you do for solar panels when the thing is round? Could a round panel-covered object still gather sufficient power to run the computers that will be inside, or is the wind supposed to power that as well? Off to read the article... =)
next up... (Score:5, Funny)
Re:next up... (Score:5, Funny)
Not a short-term solution (Score:5, Insightful)
Note that the wind-propelled rover used an existing overbuilt satellite constellation [surrey.ac.uk] to communicate its data back to the engineers. The implication there is that the rover couldn't use the sort of non-androsynchronous communications satellite that is currently available on Mars. So unreliable communications is one notable problem.
Also, look at the data that were being recorded... position, air temperature, pressure, humidity, and light intensity. Position is likely hard to determine without a Martian GPS system. Even so, the rest of those parameters can be deduced from current orbiters, especially "humidity". I can tell you that now -- it's somewhere close to 0%. It's a dry heat^w cold.
The nature of the object means that those are pretty much all the sensor readings you're going to get, too... add pretty pictures to the mix, of course. But this isn't something that can bore holes in rocks or take detailed spectra of interesting spots, because there's no way to anchor the ball to the ground.
If it can be done "fast and cheap", go for it. It might give some good close-up photos of places to send a more capable lander. But I'd suggest launching another Beagle (with airbags) first, if we're wanting best bang for the buck.
Re:Not a short-term solution (Score:5, Insightful)
It seems to me that you could choose to stop the bestie at any time just by letting some of the air out of the bag. So long as you've remembered to include an air compressor in the design, you could just fill it back up using the local atmosphere when you were ready to get moving again.
Re:Not a short-term solution (Score:2, Interesting)
Re:Not a short-term solution (Score:2, Insightful)
I don't think it can get burried under sand or ice, but stuck in a deep crater it definitely can.
Re:Not a short-term solution (Score:2)
I'm wondering if there are still color cameras in the rover? An older document mentioned something about putting a pair of color cameras on the ends of the rotation axis but no mention was made in later documents.
Re:Not a short-term solution (Score:3, Interesting)
Re:Not a short-term solution (Score:2)
I also imagine that the "guts" inside one of these tumbleweed balls isn't as sophisticated as a rover.
Re:Not a short-term solution (Score:2)
I'm just thinking out loud... but maybe eight inflatable/deflatable balloons (like a sphere divided by three planes). If they were all positioned strategically on the rover they could be inflated to make it roll, or deflated and reeled in.
Re:Not a short-term solution (Score:1, Insightful)
Antenna rotation and alignment would probably be a problem though. Don't know if it would be too hard to maintain a static location and control it from Earth.
Re:Not a short-term solution (Score:2)
You mean, like this [nasa.gov]?
From the link:
HAND
GTRacer ...to the Moon, Alice!
-
this is an EXPERIMENT (Score:5, Insightful)
Re:this is an EXPERIMENT (Score:2)
If the thing lands in even a small crater (like the one Opportunity is in) it will be stuck. The typical Martian winds (in a 1% atmosphere remember) won't push a beachball out of even such a small crater, much less around a rock outcrop placed in its path. So, as designed it would only be vi
Re:this is an EXPERIMENT (Score:2)
I am a bit amazed that they think they can create something that'll have a high enough surface area/mass ration to be blown around by the very thin martian atmosphere, but still have enough radios and equipment to produce usefull information.
How can you simulate low atmosphere martian conditions? Can you make a sealed wind tunnel with a 1% atmospere and do your test at scale?
Re:this is an EXPERIMENT (Score:2)
Actually I was surprised to see on one of the NASA videos that this is how they tested the balloons used in the landing system for the current rovers. They have a gigantic multi-story metal chamber that they can evacuate to near vacuum conditions (it takes hours). So I suspect they could at least do SOME realistic environment testing of this concept.
Impractical? (Score:2)
I may be wrong of course, but I mean if we're talking about Mars we've got an atmosphere of only 1% Earth pressure (and I am guessing, similar density). Seems if you are going to blow a balloon about on Mars its got to be carrying a very small instrument payload. And a payload that can send back something meaningful while its being tumbled about and has I guess comms problems with an orbiter seems a bit fanciful.
Re:Impractical? (Score:2)
A viable, and complimentary, alternative (Score:5, Insightful)
For a real Tumbleweed-type probe more specific hardware would be used. It would undoubtedly take advantage of the martian orbiters that are already in fairly polar orbits (thus the current irregular communications windows). However for now Iridium is cheap, doesn't require extra-paperwork or expensive custom hardware, and frankly they're focusing on the novel bouncy-stuff rather then the rather straightforward comms issues.
Um, no. Again, this is stuff that could trivially and cheaply be tossed onto a proof-of-concept, not specifically what would be included on a Mars-bound probe.However we DON'T know those things about Mars particularly well. Indeed after the rovers landed a bright person figured out how temperatures could be identified for the radio transmission path and it turns out the martian atmosphere is more chaotic with all kinds of thermal upwellings then had been assumed. Getting some widely dispersed numbers of local values would be useful, particularly for confirming assumptions used in interpreting remote sensing guesstimates.
Well, ionization, lighting under clouds, dust volumes, "pretty pictures" of more of the place up close, particularly from non-flat parts, etc. All very valuable. Sure areology is important but there's a lot that can be learned from the surface and ground-level environment that doesn't require drilling holes.For comparison imagine what you can learn just walking down a street with your native senses, information that can't be gained from a spy satellite, particularly one not already calibrated for your environment. Not even manipulating anything you'll learn a lot, be able to infer and correlate a lot more. Sure a Tumbleweed probe is more limited in some sorts of sensing, on the other hand it'll likely be able to go farther and longer then a Beagle-type probe.
The question is what bang you're looking for, and what kinda bucks you can afford.Beagle-type probes can do some things, Tumbleweeds look like they'll be complimentary for others. Is it more valuable to intensely study, and even interact with, a handful of flat places or get measurements of a far wider swath of the plant? At least now we know that we've got alternatives to wheeled carts for exploring.
Re: (Score:2)
Re:Not a short-term solution (Score:2)
The implication there is that the rover couldn't use the sort of non-androsynchronous communications satellite that is currently available on Mars. So unreliable communications is one notable problem.
More likely they used Iridium because it was there (DOD bought the lot for about $0.02 on the dollar) and it was easy to get going for a quick test. There aren't that many satelites that cover the Antarctica and it wasn't worth launching one just for the test when Iridium is already there going mostly unuse
I expected to see some kind of rover but... (Score:3, Funny)
Re:I expected to see some kind of rover but... (Score:3, Interesting)
Tumbleweed design? (Score:1, Interesting)
Re:Tumbleweed design? (Score:3, Interesting)
Forwards and backwards imply a destination, but it is more of a journey.
What about... (Score:2, Funny)
Sorry, had too.
Difficult task (Score:5, Interesting)
It's not so hard to make a robot that works. It's all the possible problems that make it hard. And if your robot happens to be on Mars when it breaks... you're SO screwed!
All the little things... unanticipated terrain, sensor malfunction, wheel gets stuck... the list is endless. Of course, during my project I kept to the smooth carpet and just moved the robot whenever something happened. But these guys have got their work cut out for them.
No pressure, its just a 3 million dollar robot!
Re:Difficult task (Score:2, Offtopic)
And so did Hitler... :-)
Much fewer [atheists.org] scientists are religious -- if you compare to the general population.
It's an old observation that if you cherrypick examples from a large data set, you can get good statistics for any thesis. Of course, that is the reason it is considered less than intellectually honest...
Besides, "religious" is hardly a good description of Einstein [stcloudstate.edu]. Also, Newto
The unfair moderation. (Score:2, Insightful)
Nitwit Moderators! (Score:2)
Nitwit Moderators -- this was more "Interesting" than "Offtopic"!
Re:The unfair moderation. (Score:2)
Re:The unfair moderation. (Score:2)
Until quite recently, pretty much *everybody* believed in a god. So pointing out that famous scientists did so means nothing. So did everybody else, including a number of truly terrible people. Their belief in god has nothing to do with their work in science any more than Hitler's belief in god had anything to do with his attrocities.
Einstien's "god" that he believed in was NOTHING like the god described by any major religion. It was pretty much just "Wow, the uni
Broad purpose robot (Score:4, Interesting)
What about crevasses? (Score:5, Interesting)
Re:What about crevasses? (Score:2, Insightful)
It made it across antarctica, if you'd had RTFA.
Re:What about crevasses? (Score:3, Informative)
In fact, the prototype made it across a relatively well-mapped out ice sheet. We, on the other hand, can only do our mapping of the martian surface by satellite. A relatively shallow crater or unmapped obstruction still strikes me as being a show-stopper. This may well not be the case at all, but I'd like to know why -- maybe Surveyor has a high enough resolution that this is not an issue. If not, maybe future orbiters are planeed that do.
Re:What about crevasses? (Score:2)
It did travel 70 kilometers across the Antarctic Plateau. It doesn't say where it stopped.
At last report it was halfway across the Indian Ocean on a course to Australia. :-)
Re:What about crevasses? (Score:2)
Having just finished Bancroft/Arnesen's No Horizon is so Far, I'm impressed it made it. The Antarctic ice is anything but flat for large areas.
this would be a Good Thing. (Score:2, Insightful)
As you say, if you dropped multiple cheap inflatable probes in one go, they will go off and "find" their own interesting places. Add a "deflate" feature for when it gets there/if it crosses something interesting but flat, and there you go.
Astrobiology Magazine Gets its math wrong (Score:5, Informative)
The ultra-durable ball reached speeds of 30 kilometers per hour (10 miles per hour) over the Antarctic ice cap
Do you think that someone should tell Astrobiology Magazine that 30 kph is about 18 mph? That's almost double the mph that they give the rover credit for.
Re:Astrobiology Magazine Gets its math wrong (Score:2)
Re:Astrobiology Magazine Gets its math wrong (Score:2, Informative)
Re:Astrobiology Magazine Gets its math wrong (Score:4, Funny)
Re:Astrobiology Magazine Gets its math wrong (Score:2)
Re:Astrobiology Magazine Gets its math wrong (Score:3, Funny)
Tumbleweeds (Score:2, Funny)
Re:Tumbleweeds (Score:1)
I think they are targeting the flatter polar ice caps instead of rock or dust deserts. There are probably too many places to get stuck around rocks, craters, etc. They would probably need some kind of air nozzle or rockets to get out of tight spots if they roll around rocks and crevices. But the ice caps are probably pretty flat. However, I wonder what happens if such a thing got stu
Rover (Score:1, Redundant)
Pelt the planet with these things... (Score:3, Interesting)
Then have a mothership satelite or two orbiting trying to pic up a ready to transfer signal from the units and relay the data back to earth.
Re:Pelt the planet with these things... (Score:3, Funny)
BAP
Aeriouloo: I'm telling Dad! He said not to pop any more of those. You are SO goona get grounded.
Eiixpi: Don't be a tattle tail. I don't see why we can't pop 'em anyway.
Aeriouloo: Dad says if all their rovers pop, the earth people might figure out we're here and try to collonize us.
Eiixpi: What's he afraid of? They can't be that dangerous. Look at their rovers...
UofA alternative. (Score:5, Informative)
For some reason I remember back in the late 1980s the University of Arizona students considered doing something like this. Rather than simply having the wind roll it around, they thought about using pumping fluids. (iirc). They decided against the ball design for fear that it might get stuck somewhere and couldn't get out.
Instead they came up with 'rover' that had two wheels that were inflated in pie sections. It looked like a giant axel with no car attached. It had a nonrotating middle where the instruments, etc, were supposed to be placed. IIRC, they actually tested it out in the desert.
A quick google doesn't turn up anything. IIRC, it was called the 'Mars Ball' and I read about it in Discovery magazine circa 1988, but I might be off +/- a couple years. At the time, I loved it. It was simple, yet seemed rather well thought out and flexible.
Anyone have any good pictures or articles online?
Re:UofA alternative. (Score:5, Informative)
Not exactly kosher to follow up to one's own posts, but...
Here's a PDF with the abstract [arizona.edu] for the Mars Ball. 1988 was the year in question.
Serendipity (Score:4, Interesting)
I'm in the wrong business! (Score:2)
I guess I'm in the wrong business.
fascinating piece of 'art' (Score:1, Informative)
Is it going to get to Mars in 3 weeks now too? Let's do some quick rover math...
Distance to Mars 34.65 million miles Original Rovers got there in 3 weeks according to NASA
3 weeks (21 days) 504 hours divided by distance? 69023 miles per hour
Those are some fast little 'ships' even if it took 6 months (180 days) it would have to travel at 8020.8333333333333333333333333 to get to mars. A year? Oh you get the point. It's a conspiracy I tell you [politrix.org]
Re:fascinating piece of 'art' (Score:2)
Non-wheeled rovers are not new (Score:4, Interesting)
Hold on a second... (Score:4, Redundant)
Doesn't seem like the swooshing of the diffuse Martian atmosphere would provide enough force to shove even a highly-engineered tumbleweed around...
Re:Hold on a second... (Score:1, Insightful)
Obviously these guys, who've dedicated their lives to this field of study, seem to think it'll work. I'll take their word for it.
Re:Hold on a second... (Score:2, Funny)
Mars atmosphere + wind (Score:5, Informative)
--
For news, status, updates, scientific info, images, video, and more, check out:
(AXCH) 2004 Mars Exploration Rovers - News, Status, Technical Info, History [axonchisel.net].
We have good and bad news : (Score:5, Funny)
What about Mar's thin atmosphere? (Score:5, Informative)
This means that it would require a wind about 10x as strong as here to produce the same amount of force on something like this rover.
Fortunately, the gravity on Mars is about 1/3rd of ours, so in theory you'd need only about 1/3rd as much force to move your giant beach ball, so I guess you could get the same amount of movement on Mars as you do here with only 3x as much wind.
(Some more thoughts along this line can be found here [x-plane.com], which is a page about a simulated plane flying on Mars.)
Apparantly Mars does have strong winds [bbc.co.uk], so maybe this isn't as crazy as I first thought :)
As an example, the article talks about a 20 m/s wind on Mars -- that would produce the same thrust on a stationary object as a 2 m/s wind would here on Earth -- not very much. But once the object started moving, the thrust would not drop off as fast as it does here (after all, wind won't usually push something faster than the wind is going) so if the ball was light enough, it might actually move at a decent clip. But it would have to be very light.
Re:What about Mar's thin atmosphere? (Score:2)
Re:What about Mar's thin atmosphere? (Score:2)
Yes, I'm fully aware of Newton's second law. But I'm talking about friction, not F=m * a.
As a rule of thumb, it's twice as hard to push something twice as heavy, everything else being equal. This applies to rolling friction as well. I'm not talking about acceler
Re:What about Mar's thin atmosphere? (Score:2)
As long as the wind is strong enough to overcome the friction trying to keep it still, they won't really care how fast it accelerates. They can wait a few minutes as it comes up to speed :)
Mc Donald wrapper (Score:5, Funny)
Some improvement suggestions (Score:4, Interesting)
First off, to get some of the positional data in a fashion similar to using the Earth's Iridium satellite network, NASA could drop some RF triangulation devices on Mars. This seems like a cheap, viable option to me.
I would think NASA would like to have their "tumbleweeds" stay parked when something fantastic was found. Perhaps the probe could drop anchor now and then. I'm thinking a magnetized metal disc could be dropped outside the ball and attract to an electromagnet inside the ball. When the engineers are ready to let the ball move again, they switch off the electomagnet's current. Given six disposable discs, a ball could be anchored six times and no need for a motor or drilling system.
Also, how about a kite and harness rig? If the ball/probe needs to make a long run, it could have a harness around it attached to an axle running through it. A kite, attached to the harness, would then be launched from the probe and set it off on a faster run than just having air blowing against a ball on the Martian surface. The harness and kite could be dropped if the probe needed to "be free".
BTW, I highly recommend actually reading the links referenced as I am already seeing a lot of duplicate comments here as in previous discussions. Moderators in particular should check those links, unless you like modding up dupes...
Great (Score:2)
Re:Great (Score:2)
On a planet we know practically nothing about at all yet, it comes pretty damn close.
Sort of reminds me of some crappy sci-fi i saw (Score:2)
I also vaugly remember something about a town in that show.. I just remember it looking strange because the town itself looked like something out of disneyland.
Re:Sort of reminds me of some crappy sci-fi i saw (Score:2)
It wasnt so much scifi as a surreal show, where very little made sense and nothing was explained. The village actually exists (Portmeirion [portmeirion-village.com], in Wales UK) and was built mostly by a single person over a period of 50 years. The balloon you mention is the security
This looks like a good idea. . . (Score:4, Funny)
Re:This looks like a good idea. . . (Score:2)
You think their great now... (Score:3, Funny)
Get me off of this island!
Yours Truly,
No. 6
Lots more info (Score:5, Interesting)
Some early research [nasa.gov]
Video [nasa.gov] from June 2001.
J
oh, the name... (Score:3, Funny)
Sorry in advance, folks.
Do not taunt... (Score:2)
Sail Power? (Score:3, Insightful)
Re:Who is number one? (Score:3, Funny)