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New Software Stops Mars Rover Confusion
MattSparkes writes "The Mars rover Spirit used to get quite confused when it came upon a rock. Because it could only plan routes of a metre or two it couldn't understand how to navigate around large objects, and frequently used to rock back and forth for hours trying to figure it out. NASA have written new software called D* for the rover Opportunity, which should allow it to autonomously plan routes up to 50 metres long. The new software still won't be able to avoid sand-traps, though."
actually controls the rail gun which will be used to 'eliminate' obstacles
Do not try to read the dupe, thats impossible. Instead, only try to realize the truth
What truth?
There is no dupe
..and I can't avoid sand-traps either!
I'm guessing the name is meant to suggest similarities to A*, but you think they'd mention that in the article.
Ben Hocking
Need a professional organizer?
They fixed the navigation issue, but I bet the rover still hates Mars.
You know, NASA sometimes has a hard time figuring out the difference between Meters and Miles. Now, you are asking them to figure out the difference between Metres and Meters.
Every time it would figure out a way around the rock, Marvin would move the rock.
Ha!
This story is a perfect illustration how stupid the current generation of state-of-the-art AI is (or lack of).
Anyone who ever said `there aren't any opportunities in IT', try to solve this problem!
"If anything can go wrong, it will." - Murphy
The Warcraft engine knows the dimensions of the rock... It's responsible for rendering it. The rover, however, knows only what it can see.
Your orcs didn't gather 2d data from 3d stereoscopic cameras and have to map it to an incomplete perception of 3-space and then have to navigate in 3-space, where one misinterpretation could mean the end of a mission costing hundreds of millions of dollars.
Stop it, stop it, it's fine. I will *destroy* you.
Maybe the path they had originally intended the rover to explore did not involve going around any large objects? Remember, these things were originally designed to last only 90 days.
Had they known the Rovers would last this long, they probably would have put instrumentation on them capable of detecting things other than water (like the instrumentation that was on the ill-fated Beagle 2) in addition to more sophisticated navigation software.
My orcs could find their way around rocks... (Score:0, Troll)
Anyone else find that mildly amusing?
The slashdot moderation system is broken and penalizes humor in spite of the fact that the readership overwhelmingly supports it. Thus some people moderate using some other positive mod than funny, since funny does not give karma, but being modded funny and then being modded negatively does TAKE karma. HTH, HAND.
"You're right," Fisheye says. "I should have set it on 'whip' or 'chop.'"
Because they were originally intended to last for 90 days. There were no "long treks" planned. People assumed that maybe they'd survive a teensy bit beyond the 90 day mark and there was pretty wild celebration (for a bunch of nerds) at the 100-day mark because people thought it was really cool. Now, a thousand+ days later, these little guys are still going strong.
This kind of engineering quality is the reason why JPL is the only organization on the planet that has ever sent enything past Mars orbit. They're considerably more expensive as just farming out your hardware to Lockheed (ahem), but instead of crashing into things they actually land and work properly.
We're all born with nothing.
If you die in debt, you're ahead.
Pathing in a video game is (by comparison) easy because you don't have to translate into the real world.
Think about what goes into pathing in the real world for a moment. You have to consider the terrain you're crossing and anything else that might get in your way. You have to be able to revise your model intelligently as you get closer to things and get new sensor data. The whole problem is immensely complex.
In a computer game, the entity pathing already knows precisely where every object is in the map any time it wants to think about it. It knows precisely where it is. It knows exactly how fast it can move at all times. If there even is any difference between various types of terrain, the precise result of being on each type of terrain is known (and thus probably loaded from a precomputed table.)
The only thing easier in this case as compared to, say, pathing in a FPS, is that Mars can be modeled as a heightfield. The rovers are not going to be traveling on bridges any time soon (although that would certainly be news.)
"You're right," Fisheye says. "I should have set it on 'whip' or 'chop.'"
> Look L
To your left you see a sharp precipice going nearly straight down. Sticking out of the cliff wall are thorny bushes.
> Look R
To your right you see an overgrown thicket, filled with poison ivy, snakes and thorny bushes. The remains of a trail appear to pass through the thicket.
> Climb boulder
You grab hold of the boulder and attempt to pull yourself up, but lacking a firm grip, you slip and hit the ground with your butt.
I'd agree with you, but the chance that the lander would land close to an object that is 'large' is too great a possibility to not have accounted for it? When writing code, you should always look to trap or overcome any circumstances that might confuse/cripple/kill your program. The same goes for autonomous vehicles.
As an example, hobby robotics poses a simple problem that is very much like the one the rovers face: how to run around the house all day and "not get stuck behind the couch" with limited sensory facilities. Say you were to take a Lego robotics kit and try this, it's not easy and takes quite some engineering skills. I'm just surprised that the rover developers didn't account for this. It *IS* impressive how they are able to modify the code and upload it though.
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It seems since the first year, the rovers have been more useful as a means of testing robotics software than as a means of studying geology.
When the problems on this planet make it uninhabitable, it'll be nice to know what Mars is like before we try to move there.
And in comparison to the federal budget for social security and the military (combined something like 85% of the total budget), a few million for a Mars rover is a drop of the bucket.
It's really a question of values, and what you consider to be "problems" that are more important. That's a subjective judgment, and you can't really say it's "wrong" to spend money exploring Mars.
Some NASA software engineer reading slashdot is probably shitting his pants right now because he wrote the config line:
MAXSEARCHLENGTH: 50 yards
"Can I come home now? When I agreed to go to Mars I was told it was a tropical paradise and I would only have to stay for three months. It's cold and dry and I haven't seen a single palm tree, not one! The software update was a big help but I'd rather have a ticket home." Signed Spirit Rover. "I miss you guys. By the way who won the last three American Idols? Reception sucks up here."
Yes, D* has been used "live" for the first time.
However, both rovers received a fresh load of mission s/w a couple of months back which enables a variety of fabulous new functions, including "go and touch" (as opposed to the original "touch and go") - go and touch enables the drive planners to instruct the rovers "move 12.4 metres forwards, turn 30* left, forward 70cm, approach the rock in front of you, deploy the IDD (robot arm holding a variety of instruments, spectrometer, close up camera, the RAT (grinder) and brush, etc; deploy the Mossbauer spectrometer, take reading in situ for 18 hours".
It also enables them to build their own route maps. One problem is that on featureless plains, it needs landmarks to assess how far it's travelled -- thus the newly developed "drunken sailor" manouever, designed to make clearly visible tracks that can be used to triangulate the on-board navcom. thing.
"None are more hopelessly enslaved than those who falsely believe they are free." -- Goethe
The rovers can be manually commanded to perform specific driving maneuvers (and the beginning of each drive usually is done by manual planning). It's not a problem.
Stop it, stop it, it's fine. I will *destroy* you.
Thank you for letting us know and even providing a link to the tech report.
Here's one that that really bugs me about online news articles: they rarely take advantage of the medium! Why the hell couldn't New Scientist provide a link to this paper? As the parent mentioned, the very least they could have done would be to mention that it was related to A*. Yes, I realize that the "average reader" (whatever that means) may not want to know such details, but why couldn't they include a simple "(details...)" link right next to the mention of D*? An interested reader could click on the "details" link and expanded text would create a brand-new paragraph describing more details of the algorithm and providing a link to the tech report. Click again, and the detail paragraph collapses and you go back to reading the basic-version of the story. Simple!
These publishers haven't grasped the power of the new media. For them, online articles simply mean that it's faster, easier, and cheaper to publish stories. Basically, they embrace web publishing for their own selfish reasons. With just a modicum of thought, they could make their products much more valuable to the consumer. But I suppose that would require them to give a damn about their work.
GMD
watch this
"My forays into hobby robotics tells me that this isn't as easy as it first appears it might be."
Thank you. I program autonomous vehicles, and people sort of stare at me blankly when I tell them I've spent the last few months of my life trying to detect the color of a traffic light. People often take for granted their ability to sense the world around them. I can assure you, robots do not take that for granted...
These publishers haven't grasped the power of the new media. For them, online articles simply mean that it's faster, easier, and cheaper to publish stories.
For them, it's about entertainment and distraction, not about providing information. Entertainment is much more profitable and less labor intensive. Personally, I wish those who submit articles would link to the very original source, instead of a fluff piece from CNN.
What?
Here's one that that really bugs me about online news articles: they rarely take advantage of the medium! Why the hell couldn't New Scientist provide a link to this paper?
Because science journalists and editors know nothing about the fields they report on, and frequently seem actively hostile to the facts in favour of some made-up, mythological story.
Some years ago a colleague at the university where I was a post-doc came into the lab and said, "Today the science section of the LA Times has five stories about stuff that I am either personally familiar with or have actually worked on. Four of them are all but unrecognizable. The fifth is full of things that are not true."
In my subsequent experience as a scientist I have found this to be pretty much par for the course for science journalism. I don't actually know if reporters are as ignorant as they appear, but by the time the edited work gets to the reading public it is almost always spun in such a way as to be misleading or simply wrong.
There seem to be some myths about science that are the bedrock of science reporting, and reporters or editors will distort or simply lie to ensure they reinforce those myths. Some of them are:
1) Science is mysterious and full of contradictions (see yesterdays "hot ice" story)
2) There is no point in anyone trying to understand science, it is beyond you (thus the lack of useful links in stories)
3) Scientists are either put on a pedestal or dragged through the mud. They are never treated as merely ordinary people doing a job or following a vocation.
4) The "story" is more important than the facts.
There are probably a lot more, but basically, science journalism will never be worth anything until it starts actually reporting on science rather than wasting time promulgating editorial myths.
Blasphemy is a human right. Blasphemophobia kills.
My Warcraft II orcs couldn't find their way around a 2-tile big forest. My Terran Marines, however, could find their around lots of stuff. But, obviously the marines are from the future, where this technology is better.