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Mars Rover: Tumbleweed Models
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."
By knowing the landing location, you can extrapolate where you have gone if you have am original bearing and known travel direction.
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A link about things like this:
http://www.nasatech.com/Briefs/Nov01/NPO21235.h
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/ast31ja
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
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?. 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."
But to pedanticaly correct you:
North Carolina State University girls rock!
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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?
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I don't really like the idea of any sort of "seed" probing like that
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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
Those who do study history are doomed to stand helplessly by while everyone else repeats it.
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. The fan speed was low, MUCH less than some of the crazee whirlwinds on Mars, and pretty accurately approximated the volume of air moving given the much greater air density on Earth.
The only model that consistently tumbled over half the length of the tank was a small Styrofoam ball, with wooden sticks poked into it with little plastic discs attached to the ends of them. It had the most outside surface area of any of the models.
They also had a full-scale model of the Sojourner robot. That was cool. It looked expensive.
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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 fiber ribs, some sort of anchor for times when prevailing winds were in unfavorable directions, and changing the mass distribution and inertial characteristics. However, I think the point is that they wanted a simple, lightweight, easily reproducible design; the whole idea of a tumbleweed is based on utilizing what you don't have to bring along (interestingly enough, it was first thought of when a test rovers wheel blew away and escaped the crew out in the desert, I believe).
I remember their presentations mentioning research they did on the atmosphere and typical wind climate, average surface qualities (rock size, etc), and how it would affect their design. The biggest concern I heard judges from industry at the southeast AIAA student conference (http://www.AIAAstudentconference.org) echo was over oddly shaped debris gathering inside the design and weighing it down.
The pictures you see on their website are from the senior design picnic less than a month ago. The actual design is even larger. The wind was calm, but it would only take about a 10 knot gust to start rolling. And yes, the girls in the pictures are real engineering students, and I know them all- don't worry, they're a lot smarter than to let you guys explore any surfaces. But I'll let them know you brought it up. Also, Dustin isn't copping a feel. I think his family was a few yards outside that picture, but it does look sort of funny.
If anyones curious, look up our design project too (http://www.mae.ncsu.edu/courses/Mae478-479/team3/ webpage/frameset.htm)
on a hopefully soon-to-be autonomous 200 knot jet aircraft (pretty decent for
~12 lb. thrust). The section pages are still empty, but there are lots of pictures
and a couple videos.