The Rovers That Just Won't Quit 299
smooth wombat writes "Like the Energizer bunny, the two martian rovers just won't quit. Spirit, after climbing to the top of Husband Hill during the past year, spent two months examining rocks at the top of the hill and scientists confirmed that those rocks were similar to rocks found along the side of the hill indicating that Husband Hill is probably the result of an impact crater.
It will take about two months for Spirit to make its way down the hill after which the next target will be a feature called Home Plate located about a half mile away.
Opportunity is exploring the northern rim of Erebus Crater, the largest crater between already-explored Endurance Crater and its next destination, Victoria Crater.
The rovers were only supposed to last three months but have been operating for almost two years. NASA has also released a 360 degree panorama of images taken by Spirit as it explored Gustav Crater."
Read this book. (Score:5, Informative)
I read Roving Mars [amazon.ca] a few months ago. It was written by Steven Squyres, the principal investigator for the Mars missions. A very good book with some behind the scenes scoop on the politics and squabbling involved in getting these things build and sent. Highly recommended.
Re:Read this book. (Score:3, Interesting)
Re:Read this book. (Score:5, Informative)
Re:Read this book. (Score:4, Interesting)
In fact, the first day of class, he said that the entire class was "off the record" and I don't think he even wanted the college newspaper students in there. (and i'm only disclosing that above story because it's obviously ok to say now. but... his others stories stay with me!). - All Cornell Ugrads - make sure to take his classes! (and Jim Bell, another AWESOME astro prof - wrote me my recommendation for med school).
I wish my Wife's Friend (Score:5, Funny)
Re:I wish my Wife's Friend (Score:3, Funny)
Re:I wish my Wife's Friend (Score:2, Funny)
Even lamer pun (Score:5, Funny)
Re:Even lamer pun (Score:2)
Re:Even lamer pun (Score:5, Funny)
visit their blogs (Score:4, Funny)
http://www.livejournal.com/users/opportunitygrrl/ [livejournal.com]
and
http://www.livejournal.com/users/spiritrover/ [livejournal.com]
It's the ultimate hack (Score:3, Funny)
It's a martian university information technology research project. the local martian college geeks have hacked into the systems and are feeding them a virtual reality data stream of what they want us poor earthlings to receive as data. The trick is to see how long they can keep us going.
the two systems are actually sitting inside a research lab in separate rooms in a cave someplace on the northern slope of Valles Marenaris [sp?]
Everything is simulated in glorious high preci
Larger version... (Score:5, Informative)
Re:Larger version... (Score:5, Funny)
All you fans of sterile deserts say WHOOOP!!! (Score:5, Funny)
-Eric
Re:All you fans of sterile deserts say WHOOOP!!! (Score:2)
The kind of place you and I know to exist, but will never see it with our own eyes.
Re:All you fans of sterile deserts say WHOOOP!!! (Score:3, Interesting)
Larger pictures? (Score:4, Interesting)
Re:Larger pictures? (Score:3, Informative)
- Opportunity panoramas [nasa.gov]
I'd assume all there are available in anything from small to huge images in typical NASA fashion.
The other side of the crater... (Score:5, Funny)
The bot went over the crater, the bot went over the crater
The bot went over the crater, to see what he could see.
And all that he could see, and all that he could see
Was the other side of the crater, the other side of the crater
The other side of the crater, was all that he could see.
Re:The other side of the crater... (Score:3, Funny)
Could be a problem? (Score:4, Insightful)
For two reasons:
1. It raises the expectations for the duration of unmanned missions. If future missions don't last as long people will obviously compare it to these.
2. Funding. If the perception is these craft last a long time then maybe people will say you don't need as many.
Re:Could be a problem? (Score:3, Interesting)
Re:Could be a problem? (Score:5, Interesting)
But perception of "how much we need" is a much thornier problem for the administrator of NASA. Success is always good; few people have any idea how much this costs, and most are sort of resigned to the few bucks per person this mission costs. In return they get to be The Country That Explores The Planets, and people are willing to pay a lot for that kind of pride.
What gets people ticked about the price is failure. It maakes people feel like laughingstocks in front of the world. Few people really understand the science, or benefit directly from what we learn about Mars, but they feel good that it's us who discovered it. They feel like the most advanced country in the world.
So I wouldn't worry about people saying, "Yeah, we know quite enough about Mars." That's a mission people can get behind, as compared to (say) a war costing 1,000 times as much. The war may accomplish more (depending on whom you ask) but Science (with a capital S, the vague and mysterious one, as opposed to the lower-case-s "science" where we actually learn stuff) is always popular. At least when it wins.
Hmmmm (Score:5, Insightful)
Re:Hmmmm (Score:3, Insightful)
Except that a lot of the data will be redundant. Fixed time based on type of data for analysis, variable time based on quantity of data.
Not to say that the extra data is worthless, or that it can't provide additional insight... but some of the data is just increasing sample size.
Besides
Re:Hmmmm (Score:3, Informative)
Also the probability of finding something out of the ordinary get's higher with more data. If on 1 in a 10000 pictures would capture some rare kind of rock in mars, with the extended lifetime of the rovers it will be more probable to find that rock, among the data.
Re:Hmmmm (Score:2)
Good point on the likelihood of finding anomalies. And the time spent on those is really dependent on the quantity of them, as well as the type.
Re:Hmmmm (Score:3, Funny)
No one reads the data. They put it in a box with a swastika on the side and cart it of into some huge government warehouse.
WTF? That's NEVADA! (Score:5, Funny)
conversion error? (Score:5, Funny)
Re:conversion error? (Score:5, Funny)
Re:conversion error? (Score:5, Informative)
One of the designers gave a presentation to our conference the day after they landed. It's easy to say they sandbagged their estimate, but they have had a host of challenges such as
So yeah, say they sandbagged it, but in reality, it was entirely possible that they could have worked only for a day (or not at all) and they would have been ostracized for being incompetent when they actually did a fine job. Congratulations to them.
Re:conversion error? (Score:5, Informative)
There was no landing foam. There were inflated bags that cushioned the impact as the lander bounced. The bags had cords attached to them that were retracted after landing to pull the deflated bags under the lander out of the way. The retraction didn't work 100%, and there was concern that the rover's wheels would get tangled up in the bags or the cords (which turned out not to happen).
The rover actually got stuck on mostly flat terrain. It was crossing some low wind swept dunes which the wheels eventually just dug into (think a car on the beach). By wiggling back and forth they were able to back out, and they added some movement rules for the auto drive that if a lot of slippage occurs the move stops so as not to dig so deep into loose sand.
Re:conversion error? (Score:3, Informative)
1) It wasn't a buffer overflow. It was a filesystem error caused by trying to add the 32,769th file to a file system which uses 16-bits to track files.
2) They didn't upload a new software version. The uploaded a script that could operate on the flash system without mounting it, so they could delete enough files to mount the flash system. They then had to re-upload some files that had been corrupted. They didn't have to upload a new OS, since it really didn't do anything wrong. The error was in
Re:conversion error? (Score:4, Funny)
THE WATER? See! See! They have been covering up their knowledge of martian water.
Voyeger (Score:3, Interesting)
Re:conversion error? (Score:3, Insightful)
Re:conversion error? (Score:2)
One thing no one is really talking about... (Score:3, Interesting)
These things are horribly over-engineered. Not that it is a bad thing they are proving so resilliant, but we're now at 8x the "designed" life span. In my mind, that means they could have probably built it half as robust and still been outstanding pieces of machinery(and alot less expensive).
I know that hindsight is 20/20, and I'm not judging the engineers poorly on this feat(quite the opposite in fact). I just thought someone might want to point that little tid-bit out...
Now, FLAME ON!!
Re:One thing no one is really talking about... (Score:5, Informative)
Re:One thing no one is really talking about... (Score:5, Insightful)
The problem is, when you build them less robust, they might not survive the landing, so you would get a zero livespan...
Re:One thing no one is really talking about... (Score:2)
P(failure)=P(crash) +P(land){P(!survive landing)+P(all other failure events after landing)-overlap}
Re:One thing no one is really talking about... (Score:2, Interesting)
Think about it like this. To make a project that is 90% sure to work it costs X dollars. To make the project 99% sure to work it costs 2*X dollars or more! As the levels of redundancy and robustness of the equipment increases the price increasess exponentially. The 99th percent costs more than the 98th pe
Re:One thing no one is really talking about... (Score:4, Funny)
Yeah , why did those engineers bother over engineering. They could
have made them out of some old beer cans and kit from radio shack.
Hey they might only have lasted 10 seconds but think of all the
money saved!
What would be the real savings? (Score:2)
This is nickel and dime stuff. And for those nickels and dimes we get over a year of solid planetary science? Where's the down side again?
And the expected lifespan might have been a lower limit on their MTBF analysis. Those are always lowball becau
Re:What would be the real savings? (Score:2)
How many people are still actively working at least thirty hours per week on the rovers (or rather, on keeping them running on learning from the
Re:One thing no one is really talking about... (Score:3, Insightful)
Space flight is hard. Landing on another planet is hard. Driving around on another planet by remote control is hard. The redundancy and robustness is built in to these systems because we know there are about 10,000 things that could go wrong, and we want to protect against these things. If we d
Re:One thing no one is really talking about... (Score:5, Insightful)
Thats a problem with your mind, not with NASA's strategy. In short, the actual construction costs of the rovers are a very small portion of the cost of a mission of this nature. Skimping on the construction isn't going to save significantly on design costs, nor is it going to reduce the cost of flinging it halfway across the solar system and monitoring it on the way.
What you call "Over-engineering" likely only increased to cost of the project by a couple of percent at most, and greatly improved the chances of success, avoiding the necessity of paying all of the overhead costs _again_ to lauch another one because this one plowed into the ground.
Penny wise, pound foolish as my Grandma would say. :)
Re:One thing no one is really talking about... (Score:5, Insightful)
If I may interject, WHO says they're overengineered? In fact, to the best of my knowledge they are anything *but* overengineered. When the Spirit rover had technical difficulties shortly after landing, one of the things that came out was the lack of backup systems and the inability of the craft to keep its solar panels clean. Things that many of us wished the rovers had were RTGs, Solar Panel Wipers, Longer Lasting Batteries, Redundant Computers, Larger Storage Capacity, Anything but Vx[Doesn't]Works, etc. NASA hadn't put many of these goodies onboard because the rovers were built in a relative hurry, with all expectations of short lifespans.
Unexpectedly, it turned out that pretty much all the components on the rovers far exceeded their expected lifetimes. As far as the engineers are concerned, the solar panels should be caked, the batteries shouldn't hold a charge, the wheels should be gunked up, and the computers should have no remaining capacity. Yet the rovers live on. Very puzzling for the engineers, but very nice for the scientists.
Re:One thing no one is really talking about... (Score:4, Informative)
Very true. The entire MER program was mass-constrained from the get-go. They barely fit on the launch vehicle. At some points during the design cycle the mass margin was negative, and the systems engineers had to hunt around for things to take off. There was no room to spare for over-engineering, because there just wasn't any spare mass for anything other than the bare minimum to achieve the mission. I speak from direct knowledge here, because I sat through the debates about whether or not to have two transponders (final decision: one - the SDST was considered reasonably reliable), and similar debates about the solid-state power amplifiers (the final word I heard was two SSPAs, due to their potential for failure, but that may have changed after I left the program). We used to joke that the only redundant things in the entire systems were the heaters and the SSPAs.
Re:One thing no one is really talking about... (Score:2)
So, they planned for the worst case environment on Mars and found things more hospitable. Lucky us.
Re:One thing no one is really talking about... (Score:2)
Re:One thing no one is really talking about... (Score:2)
Perhaps they were not so much "over-engineered" as much as conditions just weren't as harsh as were expected. There is a subtle difference. Like say the Martian dust was not quite as plentiful, sticky, or abrasive as engineers were led to believe. That certain items would be built more robust than necessary in this case is due to poor specifications rather than overzealous engineering.
Or perhaps NASA is
Re:One thing no one is really talking about... (Score:2)
Re:One thing no one is really talking about... (Score:3, Informative)
1) dust
2) batteries not maintaining a charge
3) Cold cracking circuit boards/frezing batteries at night
4) not enough power in the mars winter to keep from waking in safe mode each morning
5) accedents (getting stuck)
6) Some other mechanical failure
7) landing somewhere trapped or unable to get off the pad.
This is what I recall from reading articles about the pro
Re:One thing no one is really talking about... (Score:2, Insightful)
Re:One thing no one is really talking about... (Score:2)
there. They are over engineered because they don't want it to break
down during the first 30 days and waste the mamoth cost of getting
them there in the first place.
Re:One thing no one is really talking about... (Score:2)
Re:One thing no one is really talking about... (Score:2, Interesting)
Re:One thing no one is really talking about... (Score:4, Informative)
They aren't over engineered for the environment they were expected to operate in. Our understanding of the martian environment led the engineers to believe that the solar panels would become dirty quickly. I'm sure cleaning systems were considered but a desision was made to have rovers that lasted 3 months without a cleaning machanism. Turns out we didn't understand the martian environment all that well and wind is keeping the panels clean enough to power the rovers. That's just shear luck.
As for the other parts of the rovers out lasting their usefulness - well that just goes to show how good some areas of engineering have become. Yes they could probably have fitted wheel bearings that would seize after 3 months but as they would weigh the same as (or damn near) the ones that have lasted 2 years a desision was made to fit the better bearings. There will always be one weakest component in this case our best guess at what is was was wrong. I'd be interested to know what part eventually fails and kills the rovers. If nothing else this is an interesting experiment into long term rover deployment. I am sure the engineers are getting plenty of interesting telemetry back on what is failing on the rovers.
Re:One thing no one is really talking about... (Score:4, Interesting)
For example you don't talk about robustness of a strut, you talk about strength and fatigue. You don't talk about robustness of an robot, you talk about manuverability and degrees of freedom. You don't talk about robustness of a Mars Rover, you talk about sensors, speed, solar panel life, etc.
Now before you poo-poo this, name one parameter that is best described by robustness, rather than an actual engineering term with real units.
(of course we filled the final presentation for that professors course with all forms of the word, including robustitude)
Why not more? (Score:5, Insightful)
Oh, that's right... NASA's main purpose isn't exploration or science, it's to preserve its own existence. New projects mean new money, and old sucesses are only good for arguing for more funding for new toys.
Erik
Re:Why not more? (Score:2)
Re:Why not more? (Score:5, Funny)
Slant the panels and build in a small vibrator.
Man, this all sounds oddly offensive. ;-)
Re:Why not more? (Score:2)
Re:Why not more? (Score:2)
Now, disregarding these features, and just concentrating on how to avoid having the solar panels opaqued: maybe an electric field could keep the dust away. An electric field, even a strong one, in the absence of any gas to speak of, could be very energetically cheap to maintain.
Mechanical wipers are probably out of the question, due to the abrasive nature of the dust.
Re:Why not more? (Score:3, Insightful)
Re:Why not more? (Score:2)
As for saying that universities/offices/homes could be driving the rovers around. Well that is daft. The moon is not some big RC ra
Re:Why not more? (Score:2)
Well, duh, it's a government agency.
That's a primary purpose of all governments -- to preserve their own existence.
Not to say that government agencies, and governments in general, can't do things that are in the public good. On the individual level, people in government are often motivated by partially (even sometimes mostly!) altruistic reasons. But there are finite resources to be had, so on the institutional l
Re:Why not more? (Score:3, Interesting)
Instead they came up with the idea that we should switch to manned missions again and it will take 10-20 years.
The robots are already can already do alot of the exploring fo
Re:Why not more? (Score:2)
Of course, the success of the rover program doesn't just mean that the rovers are
Re:Why not more? (Score:3, Interesting)
Testament to JPL (Score:5, Interesting)
Good work JPL!
2 years and still no postcard! (Score:4, Funny)
What do you mean? (Score:2)
Hats off (Score:3, Insightful)
Gustav Crater? (Score:5, Informative)
Re:Gustav Crater? (Score:2)
Re:Gustav Crater? (Score:2)
Ummm (Score:2)
But seriously, Way to go little dudes. You have more energy than me. I get bored by my second bowl of cereal let alone doing the same thing for months on end.
Any ideas? (Score:2)
Does anyone have any information on how exactly these Rovers are powered? When the Rovers exceeded expectations by a couple of months, I was under the impression the end was nigh due to inevitably failing power supplies. But now it's been a couple of years and the things still have juice. What gives?
Re:Any ideas? (Score:4, Informative)
Re:Any ideas? (Score:2)
These babies are solar powered and NASA figured that dust from the atmosphere would render the solar panels useless after two months. The wind kept pushing the dust off the panels so.. there they go again.
Damn, I thought the solar panels provided partial recovery so as to extend mission life; this is great stuff.
Re:Any ideas? (Score:2)
Around the World in a Day (Score:3, Funny)
The Rover To-Do List (Score:2, Insightful)
Rover's Daily Schedule
Re:The Rover To-Do List (Score:2, Funny)
5.5 Start boring hole in rock (pun intended)
and
9. ???
10. Profit !!!
contest (Score:2, Interesting)
Take all of the money in the budget for the project, and offer it as a prize to the first person to accomplish all of the goals.
Great Link for Rover Updates (Score:2, Informative)
Cornell/Athena Updates (Pops) [cornell.edu]
Two Important Points (Score:4, Funny)
2. Now that we have the technology worked out to make a hardy, long lasting rover, can we do something about the cosmetics? Who are we kidding. These things are Imperial Probe Droids and should look the part.
A friend does Telecom for these things at JPL (Score:2)
maestro (Score:5, Interesting)
If you're on gentoo,
emerge maestro maestro-data
If not, check your distro repos or get it from here [sun.com].
finding same old rocks (Score:3, Interesting)
Ditto for Opportunity. It found those hematite blueberries and sulfur-rich layered rocks in the first crater, then saw them again in the next five craters its visited.
Some of the other things were interesting too- the dust devil movies, eclipses of Martian moons and so on.
Re:finding same old rocks (Score:3, Informative)
Re:finding same old rocks (Score:3, Insightful)
Happy Martian Birthday Spirit! (Score:3, Informative)
A mission which they may never finish.. (Score:5, Funny)
Re:Is this really such a feat? (Score:3, Insightful)
This sort of space exploration is realively cheap, considering the payoffs involved. I suggest we knock off a couple "bridges to nowhere" from our budget, or ask f
Re:Low Resolution Images.... (Score:5, Informative)