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Tumbleweed Rover for Marathon Martian Journeys
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."
More like anti-escape orb from The Prisoner.
Along the way, the beach-ball-shaped device, roughly two meters (six feet) in diameter, used the global Iridium satellite network to send information about its position, the surrounding air temperature, pressure, humidity and light intensity to a JPL ground station.
Note that the wind-propelled rover used an existing overbuilt satellite constellation 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.
Stressed? Me? Of course not. Stress is what a rubber band feels before it breaks, silly.
The article says that they wanted to test the durability of the design in a cold environment. That's proven to be a success. Don't start talking about the limitations of the device based on one experiment. The point was to test how well the wind transport design will work, and track its position using a simple, cheap, and pre-existing satelite network. This test is but one test in an ongoing process.
AccountKiller
Thats the point of dropping it on the polar caps, where it should be just a huge flat sheet of ice.
It made it across antarctica, if you'd had RTFA.
I don't need no instructions to know how to rock!!!!
The gravity is only a third of earths as well, so there'd be only a third of the friction to stop it rolling around.
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.
I don't need no instructions to know how to rock!!!!
I think it just goes as fast as the wind blows. You can't control the speed (or direction for that matter).
c++;
What does that matter? One of the chief properties of such a device is that it IS at the whim of the wind. Its record of where it went would be a record of how strong the wind was and in what direction it was blowing at any given time!
On the other hand, wind could end up pinning the thing to a large boulder or cliff face (then how would it get away?), and given that Mars has some really nifty DEEP canyons with sheer walls...
*SPLAT*
"The generation of random numbers is too important to be left to chance."
I wonder how it gets power. Presumably from dynamometers tapping into the rotation of the ball? Then you're using wind power for both movement and communications/sensing, I wonder if there will be enough given the 0.01 atm pressure on Mars.
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.
I don't read ACs: If a post isn't worth so much as a nom de plume to its author then I wont bother either.
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.
Perhaps you could use this technique to transport small rovers which can move about in the local area when it has reached it's destination.
Tricky to make sure it works alright/can communicate while jammed in a crack or at the bottom of a crevasse, but i'm sure this would be something they could work around ;)
I hate it when people put things they know are controversial in signatures. For some reason moderators think the post with the sig is on topic, but anyone responding to the sig is off-topic. That's really unfair. It means if you want to get away with propaganda - all you have to do is put it in your sig instead of in your post's body and it's considered taboo for anyone to question you on it.
Don't label something "offtopic" unless you know the topic well enough to tell what's on topic.
Why not make a rover that is sail powered, but with a movable sail that could be lowered in order to stop. The same priciple as a sailboat, but with wheels. The rover would be able to travel long distances with minimal power usage.