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Spirit Rover Makes Longest Trip Yet
ivan1011001 writes "Spirit traveled just over 88 feet in an attempt to visit the crater "Bonneville" to look for evidence of water on Mars. Engineers had hoped the rover would travel 164 feet, but Spirit didn't cover the full distance because it spent more time than initially planned studying rocks and soil along the way. This is longer than its earlier PR of 70 feet."
Actually, I'm impressed even at this. As long as nothing is failing, it gives me hope for future missions.
-Oy Vey
The latest information on Spirit's and Opportunity's adventures can be found here!
With a maximum speed of 10 feet/min, I don't think it would be avoiding any rockslides, period.
One martian day is apparently 24.7 hours.
:-)
So I guess it moved at this amazing speed?
Beware: In C++, your friends can see your privates!
Lunokhod could manage between 0.8 and 2 kilometres per hour depending on soil conditions and slope. Lunokhod 1 survived for 10 months and covered 10.54 km, Lunokhod 2 lasted only 3 months but did 37 km. I'm not sure how much of that time was 'active' since the rovers were shut down during the 14 day Lunar night.
However neither vehicle was autonomous, they were remote controlled from Earth. This is possible with a 2 second lag to the Moon, but unfeasible on Mars.
Best wishes,
Mike.
88 feet is roughtly 25 metres, one width of an Olympic sized swimming pool.
Rich
a lunar day is equivalent to several earth days. this means the russian rover could drive across the moon on solar power for much longer than spirit. the drawback is that it also had to sleep for almost 2 earth weeks at a time.
What ? Me, worry ?
Techie humor. Same reason Mozilla named their browser Firebird (sports car), then Firefox (Soviet jet).
Strictly speaking, that's not a domain of artificial intelligence, but pure computer vision. There are known techniques for building a map, given processed camera images, and there is usually no reasoning involved. Just a simple algorithm to find the shortest path. The search space is usually small enough not to warrant AI techniques.
Of course, it is possible that they are using higher-level AI techniques for finding the optimal path, but I doubt it as the classical image processing techniques are fast and robust enough for this sort of task.
With a three-second ping time, those lunar rovers could be directly controlled by people on earth, like a glorified radio-controlled model car. With a 20-minute ping time, the mars rovers have to autonomously execute a list of high-level goals transmitted from earth. Not exactly an apples-to-apples comparison.
I wonder if NASA had, at some point during the construction and testing of the rover, actually put the rover through a simulated Martian drive.
The reason is that, depending on the consistency and the texture of the Martian soil, you would probably want to build the rover somewhat differently if it's dry and dusty as opposed to rocky and uneven - much like how we build our cars and SUVs.
I suppose they probably still have data from the Vikings expeditions, but that is more than twenty years ago.
After watching that special I have more respect and admiration for the people at JPL. Alot of creativity and problem solving went into this project and I'm really happy for all of them.
Mars has some temporary cloud cover around mountains where air is forced up into cooler regions of the atmosphere. There are also some fogs and clouds around the polar caps where water vapour and carbon dioxide condense out of the atmosphere, but that's about it.
There are some beautiful images here.
Best wishes,
Mike.
... Opportunity was digging a trench in the Martian soil. I built this animation from recent raw images, and I wouldn't be surprised if NASA/JPL unveil their own version at this afternoon's press conference (6pm GMT, IIRC, and it'll probably broadcast on NASA TV.
:)
Mirror this image if you like; my ISP probably won't be too pleased if all their bandwidth gets eaten by greedy Slashdotters.
If there's an impending rock-slide, then the rover gets crushed. Remember that whatever the scientists in control see is around five minutes old, and that any directions of avoidance take an addition five minutes or so to reach the rover.
Besides, I don't believe they're letting the rover choose its own targets, nor did they give it power to override an imperative command.
*honk*
This is my sig. It's prescription, I swear. I need it for reading things... on the other side of things
You can learn more about how the rover works by downloading NASAs Maestro Program. It's a RAM hungry Javaapp that is nicely documented and let's you plan your own mission using their stripped down version of the Uplink-Browser. Give it a shot, it's pretty interesting (well, at least if you got some spare time on your hands to fiddle with it and are into Marsroving at all!).
cu,
Lispy
You might want to see this mildly humorous QuickTime movie on the official MER site detailing how the rovers get around without engineers having to shimmy the things around every other obstacle. The thing does it by itself--something the Russian lunar rovers didn't do.
Two words about the movie's beginning: Bullet time.
Vos teneo officium eram periculosus ut vos recipero is.
It's a common misconception. The Moon does rotate on its axis - but one rotation takes exactly the same time as it takes for the Moon to orbit the Earth.
Still don't believe me? Put a chair in the middle of the room (that will be the Earth). Now (slowly) walk in a circle around the chair always facing the chair. When you've completed the circle you will have faced every wall in the room - but anyone sitting in the chair will only have seen your face.
What this means for the Moon is that every part of the surface experiences a continuous day 14 Earth days long, followed by an equally long, chilly, night.
Instead of speaking of a permanent light side and a permanent dark side, it is correct to speak of a near side (the bit seen from Earth) and a far side (which is never seen from Earth).
Best wishes,
Mike.
The article is from CNN, not directly from NASA, so you can't conclude anything about what units NASA is using by reading it. If you actually go to the JPL website, it turns out that the original material from NASA uses metric units as the primary measure, with Imperial units added for ease of comprehension.
There's no point in questioning authority if you aren't going to listen to the answers.
Not to quibble but... The uplink radio delay is 150 ms AND the downlink radio delay is 150 ms, totaling 300 ms. Plus, when the interviewer asks a question there is one round trip delay (300ms) and the reviewer's answer takes another round trip delay (300ms) for a delay of 600ms ssimply from propagation delays to and from geosynchronous satellites.