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Mars Rover Opportunity Turns 8

Soulskill posted more than 2 years ago | from the its-doing-science-and-its-still-alive dept.

Mars 151

New submitter el borak writes "Never mind all the talk about the revival of the American auto industry. What may be the greatest car the U.S. has ever built is currently a tidy 78 million miles (125m km) away from this world — resting on the edge of Endeavour crater in the southern hemisphere of Mars. It was on January 25, 2004 that the rover Opportunity bounced down on Mars for a mission designed to last a minimum of three months and a maximum of just a year or two."

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151 comments

Slashdot won't report this (-1, Offtopic)

Anonymous Coward | more than 2 years ago | (#38843143)

Moderators, this is off-topic. Slashdot refuses to report a story.

According to Reuters, Apple surpassed Android in marketshare [reuters.com] by the end of 2011, confirming earlier reports by both Nielsen [nielsen.com] and NPD [gigaom.com] . 150 Android smartphones couldn't beat the iPhone 4S. With 15 million iPads sold last quarter, the tablet market is now larger than the entire desktop PC market.

Who cares? Well, in January 2011, Slashdot triumphantly reported that Android surpassed iOS in marketshare [slashdot.org] . All year, Android fans cited Android's marketshare as proof that it was taking over the smartphone industry, that the lack of centralized control was superior to the "walled garden", and that Android was "winning".

So what happened when the opposite occurred and Apple reversed Android's marketshare lead by the end of the year? Despite multiple submissions from several users, and news coverage ranging from Arstechnica to CNN, Slashdot refused to publish the story. All the sudden, it wasn't considered newsworthy despite the publication of the other story a year earlier.

This is a Linux advocacy site whose initial userbase was driven by hatred of Windows marketshare. Marketshare is still highly fetishized around here. Anything negative about the marketshare of Linux or platforms based on Linux, gets killed. Slashdot is intentionally not providing you full tech news coverage because it caters to a specific demographic of emotionally-invested users who are more likely to generate repeat page views.

Re:Slashdot won't report this (-1)

Anonymous Coward | more than 2 years ago | (#38843391)

nobody gives a shit you dumbass mactard fanboy spammer asshole

Re:Slashdot won't report this (0, Offtopic)

Beelzebud (1361137) | more than 2 years ago | (#38843461)

Seriously, it's time to get a life. If you get paid to do this, it's time for some self reflection.

Re:Slashdot won't report this (-1)

Anonymous Coward | more than 2 years ago | (#38843803)

Everyone that has a strong opinion that disagrees with mine is paid to have that opinion.

FTFY

Re:Slashdot won't report this (2, Insightful)

Anonymous Coward | more than 2 years ago | (#38844113)

This does appear to be a concerted astro-turfing campaign.

Not because it goes against the grain here at /. , but because these fucking morons are posting it in every single fucking story.

Most individuals would have given up by now, perhaps figured their point got across, but this troll just keeps on posting on and on, in every single fucking thread, every single one. Just like those fucking annoying people who post advertisements in the middle of threads.

If it has been two or three threads I could buy the idea that it was a concerned individual, but at this point no.

If it is indeed a concerned individual, and he is reading this, please stop, you are hurting your cause tremendously. You made your point quite some time ago, now you are being counterproductive.

Re:Slashdot won't report this (0, Informative)

Anonymous Coward | more than 2 years ago | (#38843609)

Slashdot is intentionally not providing you full tech news coverage because it caters to a specific demographic of emotionally-invested users who are more likely to generate repeat page views.

You are right, we really don't give a shit so shut the fuck up and go away.

There is no reason to post a story about it considering all your stupid fucking copy paste trolls IN EACH AND EVERY FUCKING THREAD YOU FUCKING RETARD!

Thank you and fuck off.

It's not a car. (0)

Anonymous Coward | more than 2 years ago | (#38843155)

Cars carry human passengers - pretty much the definition of car. This is a rover and not a car.

Re:It's not a car. (0)

Anonymous Coward | more than 2 years ago | (#38843277)

I have a remote controlled car. I've seen a train car that carried coal. What dictionary are you using?

The Mars probe has wheels, and is self-propelled. That makes it more of a car than many vehicles that can be licensed as a car.

Great engineering! (4, Insightful)

ackthpt (218170) | more than 2 years ago | (#38843173)

Can you remember the last piece of technology hardware you had which outlived its warranty? For me, most of that was stuff made in the 80's.

Considerable accomplishment, designing, accumulating all the bits, assembling it, putting it in a rocket, flying it to Mars, landing it and having it muck about in a place without AAA Roadside Service. Well done.

Re:Great engineering! (5, Insightful)

twotacocombo (1529393) | more than 2 years ago | (#38843279)

Can you remember the last piece of technology hardware you had which outlived its warranty?.

Pretty much everything I own, seeing as how most warranty terms are a year at best. No company in its right mind would design a product that would NOT make it past its warranty expiration.

Re:Great engineering! (2, Insightful)

ackthpt (218170) | more than 2 years ago | (#38843443)

Can you remember the last piece of technology hardware you had which outlived its warranty?.

Pretty much everything I own, seeing as how most warranty terms are a year at best. No company in its right mind would design a product that would NOT make it past its warranty expiration.

You don't read the same reviews I do, on Amazon ... "This thing was DOA out of the box ..." "This lasted 30 days and then died ..." etc.

Some stuff holds up well (which I theorize is inversely proportional to how much I use/depend upon) While I experience the same as these unhappy reviewers.

After the learning experiences of Hubble and the failed ("inches? I thought you mean't Centimetres!") Mars Climate Orbiter, you can expect things are held to a very high standard - because failure is so very, very expensive.

Still, we had a visitor to our local Astronomy club explain the one oversight which may ultimately doom Opportunity - dust build up on the Solar Panels. Next probe will probably have a little robotic arm and brush to sweep itself off now and then.

Re:Great engineering! (4, Informative)

edremy (36408) | more than 2 years ago | (#38843721)

Still, we had a visitor to our local Astronomy club explain the one oversight which may ultimately doom Opportunity - dust build up on the Solar Panels. Next probe will probably have a little robotic arm and brush to sweep itself off now and then.

This wasn't an oversight, it was well understood that this would happen. They've gotten lucky that dust devils have cleaned the panels a few times.

The next Mars rover is nuclear powered. There are no attempts at any kind of dust cleaning device- it would be far too heavy and fragile to be worth bothering with.

Re:Great engineering! (0)

Anonymous Coward | more than 2 years ago | (#38843787)

Still, we had a visitor to our local Astronomy club explain the one oversight which may ultimately doom Opportunity - dust build up on the Solar Panels. Next probe will probably have a little robotic arm and brush to sweep itself off now and then.

This wasn't an oversight, it was well understood that this would happen. They've gotten lucky that dust devils have cleaned the panels a few times.

The next Mars rover is nuclear powered. There are no attempts at any kind of dust cleaning device- it would be far too heavy and fragile to be worth bothering with.

We are clearly watching different episodes of The Jetsons

Re:Great engineering! (0)

Anonymous Coward | more than 2 years ago | (#38844195)

Nuclear? But what if gets there and blows up?

Re:Great engineering! (1)

geekoid (135745) | more than 2 years ago | (#38843773)

You base that on Amazon review? Are you stupid, or just mildly retarded?

Let me see.. the last consumer grade electronic that didn't live past it's warranty was. hmm. Nothing, actually.
wait, there was a monitor, but I broke it, so not their fault.

and I have been a consumer for WELL over 30 years.

I'm sure if I tried to save more and buy cheaper things my experience may not be true.

Re:Great engineering! (1)

tverbeek (457094) | more than 2 years ago | (#38843997)

One does have to be a bit brain-damaged to confuse the statistically small number of devices which fail upon first use with the overall population in which the vast majority last the full warranty period, and a smaller majority last twice that period or longer.

While I don't own anything manufactured since 2000 which has more than a dozen years of use behind it, that's due to temporal mathematics, not engineering shortcuts.

Re:Great engineering! (1)

dgatwood (11270) | more than 2 years ago | (#38844509)

It may be statistically small, but folks like me are also statistically unlucky (five dead hard drives in one year, zero laptops that made it out of warranty before their first failure, a Roomba whose motor gears broke the third time I used it—out of warranty, but only because I didn't use it enough—and a car at 110k that has a rebuilt transmission, a new starter gear on the front of the transmission, a rebuilt power steering pump, a rebuilt steering rack, new seals throughout the top half of the engine, a new metal coolant line, a new front valve cover, and now needs a new rear body control module because the door locks, the driver's side window, and the right rear blinker no longer work... oh, and it has a vacuum leak now, I think), so it cancels out.

Re:Great engineering! (1)

Anonymous Coward | more than 2 years ago | (#38844175)

You base that on Amazon review? Are you stupid, or just mildly retarded?

Do you start all of your posts by asserting the other person is an idiot, or is it just lately?

Because you're rather an asshole, in case nobody has pointed it out to you. The last several posts I've seen from your has you acting like a petulant teenager.

You've clearly been on the internet long enough to have had occasion to learn not to act like a douchebag, but you seem to be hell bent on it.

Re:Great engineering! (1)

twotacocombo (1529393) | more than 2 years ago | (#38843789)

You don't read the same reviews I do, on Amazon ... "This thing was DOA out of the box ..." "This lasted 30 days and then died ..." etc.

Oh, I read those all the time, and they're typically on cheap made-in-china shit that give everlasting life to the term "you get what you pay for". Once you come to terms with the fact that cheapest is rarely best, and start making small investments instead of purchases, your experience will be much better. I can honestly say I have not received anything that has been DOA in longer than I can remember, and the only thing I've had to file a warranty claim on in the past decade has been my Xbox 360. Not to say that expensive, higher-grade items don't occasionally arrived DOA, or fail before their warranty expires, but typically the early failure rate runs in inverse proportion to the cost of the item compared to others of it's type.

Re:Great engineering! (1)

Belial6 (794905) | more than 2 years ago | (#38843591)

I'm with you. Pretty much everything I own. If it doesn't arrive broken brand new, it pretty much runs for many times it's warranty period.

Re:Great engineering! (1)

DerekLyons (302214) | more than 2 years ago | (#38843313)

Can you remember the last piece of technology hardware you had which outlived its warranty?

Sure, my camera (Canon T2i) just passed it's warranty date a few weeks and it's still going strong. So is my 2005 era Kodak point-and-shoot. Heck, the computer I'm typing this on (an off-the-shelf at Best Buy HP Pavilion) is still going strong on it's original OS installation after nearly six years. (It's companion is a year younger and has only required the mouse to be replaced, unsurprising on a machine primarily dedicated to gaming.)
 
In fact, I can't remember the last piece of technology hardware of mine that didn't long outlast it's warranty.

Re:Great engineering! (1)

iggymanz (596061) | more than 2 years ago | (#38843685)

My Kodak DC4800 with 3.1 Mpixels is soon to be 12 years old and works fine. I wish my 2003 32" Sony CRT television would die so I can justify a modern set but it will probably last 20 years. I also have a Sony digital clock radio (with analog AM/FM tuner) that we're still using that is 22 years old.

Re:Great engineering! (1)

Krishnoid (984597) | more than 2 years ago | (#38843315)

having it muck about in a place without AAA Roadside Service.

I don't know if roadside service [youtube.com] would help in this case.

Well done.

A solar-powered car running for 8 years without any maintenance in a fairly hostile environment -- just astounding.

Re:Great engineering! (1)

ackthpt (218170) | more than 2 years ago | (#38843813)

having it muck about in a place without AAA Roadside Service.

I don't know if roadside service [youtube.com] would help in this case.

Well done.

A solar-powered car running for 8 years without any maintenance in a fairly hostile environment -- just astounding.

Makes you wonder, when people say we can't do that for consumer vehicles, eh? Where's the Can-do spirit?!?

Re:Great engineering! (4, Informative)

ColdWetDog (752185) | more than 2 years ago | (#38843939)

Makes you wonder, when people say we can't do that for consumer vehicles, eh? Where's the Can-do spirit?!?

You could, it just costs more. That said, most US made vehicles will run 100K miles with minimal supervision. My 12 year old GMC truck has really been quite reliable and could well run another 10 years. I'm part owner of a 40 year old plane that could fly for another 40 years.

Not everything is an iPad.

Re:Great engineering! (1)

charlesj68 (1170655) | more than 2 years ago | (#38844179)

Makes you wonder, when people say we can't do that for consumer vehicles, eh? Where's the Can-do spirit?!?

The hostile nature of a dry environment and thin atmosphere has nothing on the abuse afforded by the average consumer.

Re:Great engineering! (1)

sdguero (1112795) | more than 2 years ago | (#38843539)

My 1993 Honda Nighthawk 750 is doing pretty well. And still a lot of fun to ride... :)

Re:Great engineering! (1)

Pope (17780) | more than 2 years ago | (#38843689)

High five, old Honda buddy! 1980 CB400T, still truckin' along, albeit in need of some engine gasket replacements.

Re:Great engineering! (4, Informative)

Pope (17780) | more than 2 years ago | (#38843711)

Can you remember the last piece of technology hardware you had which outlived its warranty?

Practically all of it, since I don't buy horribly-made cheap crap.

Pay for quality, get quality. Simple.

Re:Great engineering! (4, Funny)

lemur3 (997863) | more than 2 years ago | (#38844071)

Of course You can afford to

Pay for quality

You're the Pope!!

  you probably bathe in a golden bathtub..

Re:Great engineering! (1)

wiredog (43288) | more than 2 years ago | (#38843775)

My 24" iMac is doing pretty well and it's 5 years old.

Re:Great engineering! (0)

repetty (260322) | more than 2 years ago | (#38844185)

My 24" iMac is doing pretty well and it's 5 years old.

Macs are supposed to last five years.

Actually, they often remain useful for about 8-years, although my 12-year old Lombard PowerBook is still in service. Can't really watch Internet video on it (they become slide shows) but, otherwise, it does whatever is asked of it (email, web browsing, word processing, etc.)

Re:Great engineering! (0)

Anonymous Coward | more than 2 years ago | (#38843781)

Can you remember the last piece of technology hardware you had which outlived its warranty?

All the time - of course, it's easier now that most manufactures have switched to 1-year warranties.

Re:Great engineering! (1)

Crudely_Indecent (739699) | more than 2 years ago | (#38844279)

Can you remember the last piece of technology hardware you had which outlived its warranty?

Every ThinkPad I've ever owned (currently on #5).

Re:Great engineering! (2)

giorgist (1208992) | more than 2 years ago | (#38844415)

Are you nuts ... things made in the 80s where a lot more unreliable. You have natural selection bias. Everything you still have from the 80s still alive is the sample you draw your conclusion. Objects have become a lot more reliable and cost less money.

Re:Great engineering! (1)

mcgrew (92797) | more than 2 years ago | (#38844593)

Can you remember the last piece of technology hardware you had which outlived its warranty?

I'm not senile YET. I'm working on an old PC for a friend who was given an old Dell with a 500 mz chip, 256 meg memory and Windows XP. The only thing wrong with it is whoever owned it before was dumb enough to load it down with crap, including 5 different AVs. The hardware is working fine (just reinstalled Windows for him, it still had the disks).

I bought my TV in 2002. My car was five years old when I bought it in 2007 and it still runs fine. In fact, I don't think I own a single thing that's still under warranty. But of course, they're not under the hellish conditions the rovers are operating in.

Where are you buying your crap, Tiger Electronics?

Turning 8 (1)

ae1294 (1547521) | more than 2 years ago | (#38843189)

Images from Opportunity show a life form consisting of a scorpion-shaped body, a disc and a 'black flap".

Re:Turning 8 (1)

ColdWetDog (752185) | more than 2 years ago | (#38843955)

Images from Opportunity show a life form consisting of a scorpion-shaped body, a disc and a 'black flap".

Opportunity was on Venus? Does JPL know about this?

Yea ok (0)

Osgeld (1900440) | more than 2 years ago | (#38843241)

1) IT did not actually put those 78 Million miles on its own hardware, its like if I ship a toyota from japan to virgina, I did not DRIVE it from A to B and I shure as hell would not add the shipping mileage to its odometer

2) Are we really that proud that something we built lasted 8 years? that's like the breaking in period for a diesel Mercedes with far more (actual, not shipping) miles on it

Re:Yea ok (2)

ae1294 (1547521) | more than 2 years ago | (#38843285)

2) Are we really that proud that something we built lasted 8 years? that's like the breaking in period for a diesel Mercedes with far more (actual, not shipping) miles on it

Mars is a harsh mistress...

Re:Yea ok (0)

Anonymous Coward | more than 2 years ago | (#38843453)

MAkE LOVE T0 ME, YoU FOOL!!!!!

Re:Yea ok (2)

BBF_BBF (812493) | more than 2 years ago | (#38843475)

2) Are we really that proud that something we built lasted 8 years? that's like the breaking in period for a diesel Mercedes with far more (actual, not shipping) miles on it

Mars is a harsh mistress...

+1 Some details to back you up, ae1294: Temperature in summer days/nights range from: 20 C to -90 C

Let's see a Mercedes work in that type of environment (even at earth normal atmospheric pressures)

Also there's been NO MAINTENANCE done on the rover for 8 years.

Yes, we should be proud, very proud.

Re:Yea ok (0)

Anonymous Coward | more than 2 years ago | (#38843339)

Oh, we're sorry we didn't consider the space rover that you built in your moms basement. How about this. Go to your local hobby shop, buy an RC car, put it together yourself, and then throw it out a 10story window on some balloons. And then keep it alive and fueled for the next 8years.

Re:Yea ok (1)

gman003 (1693318) | more than 2 years ago | (#38843413)

2) Are we really that proud that something we built lasted 8 years? that's like the breaking in period for a diesel Mercedes with far more (actual, not shipping) miles on it

Eight years, in an extremely inhospitable environment (extreme dust, an average temperature of -60C), with absolutely zero maintenance. Yeah, let's see that Mercedes run for 8 years with no oil change.

Re:Yea ok (0)

Anonymous Coward | more than 2 years ago | (#38843447)

1) the summary doesn't say the rover drove all the 78 million miles. It just says that the rover is 78 million miles away. Are you saying if you ship your Toyota from Japan to Virginia it's not actually however many miles away from Japan because it didn't drive those miles?

2) good comparison. Building a Mercedes is probably just as difficult as building a rover then lobbing it 78 million miles away with no way of doing any maintenance at all on it. I take it you don't fill up or change the oil in that Mercedes either. Maybe to make this comparison better Mercedes should launch one of those vehicles at Mars then see how far it drives after it gets there.

Re:Yea ok (4, Insightful)

PickyH3D (680158) | more than 2 years ago | (#38843507)

A break-in period that consisted of being shipped slowly on a ship compared to a violent launch on the top of a rocket, as well as the re-entry into the atmosphere of a largely mysterious planet, and finally the potentially violent landing.

Then, once in use and with the odometer actually ticking up, the Mercedes gets an oil change every few thousand miles, or every few months; it's also refueled probably every other week, at least. And it's probably not in a hostile environment the entirety of its driven life, at least without serious repair assistance.

So, yes, we really should be proud of the Opportunity for lasting for eight years while 78 million miles from a repair shop.

Re:Yea ok (2)

charlesj68 (1170655) | more than 2 years ago | (#38844245)

and finally the potentially violent landing.

You know, I might actually pay for a Mercedes, if the delivery method involved the successful deployment of rockets, parachutes and giant airbags ... that would be cool.

Re:Yea ok (1)

wonderboss (952111) | more than 2 years ago | (#38843583)

Take a diesel Mercedes. Strap it on top of a rocket. Launch it into
earth orbit for a year or two. Land it back on earth.

Get in and start driving. Your not allowed to refuel it, service it,
change the tires, or even add air to the tires.

Good luck. The Mercedes I know about need pretty regular
service by a specialized technician.

Oh, and I'd like the Mercedes to drive itself with a multi-second lag
between any command you send it and receipt of said command.

Re:Yea ok (1)

Amouth (879122) | more than 2 years ago | (#38844079)

multi-second lag is an understatement.. depending on position around the sun the one way trip for a radio signal from Earth to Mars ranges from 4.3 min to 21 min

Re:Yea ok (1)

geekoid (135745) | more than 2 years ago | (#38843843)

no. it's like Toyota building a car, all the packaging, the ship, the fuel. Sent the ship across a million mile ocean, and then flung the car 5 miles to land.

After which it unpacked itself and started driving, and 100 years later it is still driving.

And it was designed to last up to a year. You might want to understand what that means.

Medals (1)

ironman_one (520863) | more than 2 years ago | (#38843427)

I don't know what you have over there but these engineers deserve to be knighted.

Re:Medals (4, Funny)

spidercoz (947220) | more than 2 years ago | (#38843493)

Those engineers have already been honored the American way, their jobs were outsourced.

Re:Medals (2)

geekoid (135745) | more than 2 years ago | (#38843907)

Big companies need to be able to outsource so the can make money and create American jobs. -The Current republican stance.

the flipside of reliability (-1, Troll)

Sebastopol (189276) | more than 2 years ago | (#38843439)

I think it is great that the device was design to last max a year or two, and lasted 8, but on the flipside, this means they aren't really good engineers.

How can I say this?

The estimates were off by 400%~800%!!! Or more!!!

Just because they erred on the side of a good result doesn't mean the estimates are better. It means their methodology is HEAVILY padded, or if we assume +/-400~800%, they were just lucky that it didn't swing the other way. Given Phobos-Grunt, perhaps space engineering margin of error really is +/-400~800%. Although I suspect huge margins of error were thrown about in NASA>

If that's the case, huge design buffers, that means they don't understand the underlying physics/materials engineer, and had to heavily overdesign, which means there is a far more efficient design out there.

I'm not knocking NASA engineers, I'm just exploring how to shave down this margin so that they can make more efficient designs at lower cost that behave as expected.

Building something that behaves as expected is far, far, FAR more important than building something that blows away expectations by orders of magnitude. The former is good engineering, the latter is waste, or worse, dumb luck!

Discuss.

Re:the flipside of reliability (1)

ChrisMaple (607946) | more than 2 years ago | (#38843533)

Do you understand that the -400% life you consider as a possibility means it would have failed before it was built, and possibly before it was designed?

Re:the flipside of reliability (1)

Beelzebud (1361137) | more than 2 years ago | (#38843547)

This was the cheapest mission to Mars we've ever done. That is a fact. That the rovers lasted this long means we got a lot more out of our money than we thought. You're not knocking NASA engineers, but you are, and you're doing it by omitting a few key facts.

Re:the flipside of reliability (1)

Tablizer (95088) | more than 2 years ago | (#38843723)

I don't believe it's the cheapest. Pathfinder/Sojourner, for one, was less.

Re:the flipside of reliability (1)

spidercoz (947220) | more than 2 years ago | (#38843621)

They all went to the Montgomery Scott School of Engineering.

They designed these things to withstand the worst environment they could imagine and be as durable as possible since maintenance would be impossible. Maybe they overcompensated, so what? In return they got 4x the lifetime and dozens of times the science that they had hoped for, and still counting. Your complaint is idiotic. It's like complaining there's too much cake.

Re:the flipside of reliability (1)

Sebastopol (189276) | more than 2 years ago | (#38843833)

Clearly you aren't and never will be an engineer, we all have different strengths.

The point of engineering is to have "just enough cake." Not too much (overdesign), not too little (underdesign).

Re:the flipside of reliability (1)

spidercoz (947220) | more than 2 years ago | (#38843941)

Someone sounds a little bitter. What's the matter, NASA turn you down for a job?

Re:the flipside of reliability (4, Funny)

Anonymous Coward | more than 2 years ago | (#38844433)

Someone sounds a little bitter. What's the matter, NASA turn you down for a job?

Which is strange, because during his interview he kept stressing to them that he was "just good enough" for the job.

Re:the flipside of reliability (1)

Anonymous Coward | more than 2 years ago | (#38844333)

Clearly you aren't and never will be qualified to be an engineer. Hopefully you have other strengths that make you valuable to your employer, like contributing to team morale by telling good jokes.

First thing you don't understand: When the conditions in which something will be used are subject to a great deal of uncertainty, you err on the side of "overdesign". Mars is another planet about whose surface conditions we still have limited information, eight years into this mission.

Second, when the potential consequences of failure are "go grab another one and put it in service" you engineer something to be "just good enough". But when the potential consequences of failure are the cancellation of the whole project, including years of work by hundreds of people, imperial truckloads of money, more people's ongoing jobs, and the lost opportunity to profoundly advance human knowledge, you engineer something to be "substantially better than enough".

Re:the flipside of reliability (4, Interesting)

Tablizer (95088) | more than 2 years ago | (#38843653)

I think it is great that the device was design to last max a year or two, and lasted 8, but on the flipside, this means they aren't really good engineers. How can I say this? The estimates were off by 400%~800%!!! Or more!!!

Estimates were based on experience with the earlier Sojourner rover. Opportunity got lucky in that every now and then whirlwinds clean off the solar panels. This phenom was not known at the time, at least with solar panels.

And the wheels and joints have become creaky and are gradually failing. Work-arounds and adjustments to behavior have allowed it to continue. Thus, the equipment is failing, as expected. Luck and ingenuity in work-arounds should not normally be relied on for engineering duration estimates. Further, the grinder teeth have worn down and the rover is basically gumming rocks, or just brushing rocks instead of grinding.

Re:the flipside of reliability (0)

Anonymous Coward | more than 2 years ago | (#38843671)

1) Project Managers give estimates, not Engineers
2) Estimates are based on historical data, the less historical data you have the more VAR factors into your estimate.
3) This has NEVER BEEN DONE BEFORE, thus a Var factor of 4.0 is probably on the low end of the scale.
4) Calling them bad engineers because their estimation technique took into account the lack of historical data, is a disservice to both project management and engineering

5) Your an idiot. Your 'an idiot' wrote your post.

Re:the flipside of reliability (3, Informative)

repetty (260322) | more than 2 years ago | (#38844261)

5) Your an idiot. Your 'an idiot' wrote your post.

I'd like to make a helpful suggestion. When you are chiding someone for being wrong (and, he was), it's incumbent upon you to be right. That means grammar, too.

"Your" is possessive. "You're" is a contraction of "you are."

Re:the flipside of reliability (0)

Anonymous Coward | more than 2 years ago | (#38843771)

The problem is you're working on a scale that's starting at 0. If it fails at 90 days (the mission objective) that's 100% success. If it fails at 45 days, it was a 50% success.

Your scale is wrong.

The mission was for 90 days, meaning anything LESS than 90 days would count as a failure, or 0%. 45 days? 0%. 89 days? 0%.
So they were overengineered for the express purpose of guaranteeing 90 days.

Re:the flipside of reliability (1)

Belial6 (794905) | more than 2 years ago | (#38843817)

It may be dumb luck. What you have to keep in mind is that the margin of error necessary might be so high that even a good engineer cannot narrow it down to a small number. In this case, it could be the durability necessary to get the rover to run for a month is the exact same durability that would allow it to run for years.

Re:the flipside of reliability (1)

TheLink (130905) | more than 2 years ago | (#38843841)

"Opportunity cost" if the device fails before the design lifespan.

The device might be cheaper than the rockets, fuel etc involved in sending it there.

Sometimes you also need to launch something within a particular time range, otherwise the next best time could be decades or even a century later: http://en.wikipedia.org/wiki/Launch_window [wikipedia.org]

So if you launch it and the stuff fails, you just wasted many millions and many years. The scientists who wanted it there for their research might die before the 2nd try.

Re:the flipside of reliability (1)

Alotau (714890) | more than 2 years ago | (#38843861)

Just because they erred on the side of a good result doesn't mean the estimates are better. It means their methodology is HEAVILY padded

Under promise, over deliver. I wish more organizations/projects had this "flaw".

Re:the flipside of reliability (3, Interesting)

necro81 (917438) | more than 2 years ago | (#38843879)

The rover's aren't like the Deacon's Masterpiece [wikisource.org] , where every component reaches end-of-life at exactly the same time, the mission life was dictated not by component life but environmental factors. As I understand it, the relatively short life-rating was based largely on power availability. From all previous Mars landers, it was expected that the solar panels' output would drop to useless levels within a couple months of landing. And although they surely had some ideas on how to get the rovers to survive the Martian winter, they certainly weren't going to make that a mission requirement. The mission life wasn't a matter of the rated life of the motors, or the computers, or of the fatigue life of the chassis. You couldn't have really made them cheaper and still had a usable rover: a strut with a fatigue life of only a few months' driving probably may have snapped on impact, a 1-year motor would have been more or less the same size and weight, a 1-year computer would have been identical to the computer they've got.

And, really, why would you want to shave everything down to such a short life: it's not like you could have saved much money for the taxpayer - the component cost of the rovers is only maybe 1/100th the total cost of the mission. Most of the cost is in getting the rover to Mars in the first place, followed by having a full-time staff of dozens or hundreds designing, testing, and running the thing.

Re:the flipside of reliability (1)

geekoid (135745) | more than 2 years ago | (#38843881)

It would have taken more time to design and build cheaper parts.

Only idiots on /. would think the something going about it's expected life for the same money is bad engineering.

Re:the flipside of reliability (1)

kaiser423 (828989) | more than 2 years ago | (#38843887)

They were designed to be GUARANTEED to work for 3 months, which typically means that the usable lifetime is considerably longer. Pretty standard engineering stuff.

Re:the flipside of reliability (1)

Jeng (926980) | more than 2 years ago | (#38843967)

There was a bare minimum that this rover had to be engineered for. That bare minimum to make sure it worked at all is what also allowed it to last as long as it has.

This rover landed via airbags and experienced some tremendous g-forces. The rover had to be designed to survive that, just the ability to scoot around after that in a low gravity environment was cake compared to the landing.

So if they had designed this to just barely hit the 90 day limit then it might not have survived at all.

Re:the flipside of reliability (0)

Anonymous Coward | more than 2 years ago | (#38844345)

You're missing that these are _exploration_ missions. Part of that means there are a lot of variables we don't know about. That means padding the tolences a bit, but also that the unexpected _does_ happen. If the events that cleaned the solar panels had not occurred, for instance, Opportunity would probably not have lasted this long.

Re:the flipside of reliability (1)

SpaceLifeForm (228190) | more than 2 years ago | (#38844521)

This was how the project got off the ground. If it was expected to last 10 years, the budget would have looked too large, and the pencil pushers would have killed the project. Leave the techs alone, and good stuff happens.

Re:the flipside of reliability (3, Interesting)

UnknowingFool (672806) | more than 2 years ago | (#38844551)

I think it is great that the device was design to last max a year or two, and lasted 8, but on the flipside, this means they aren't really good engineers.

First of all it was engineered to guarantee to work for 3 months which was the allotted project objectives. Based on the budget and capability, this is what NASA had designed the rovers to do. Surviving for years is a bonus.

Just because they erred on the side of a good result doesn't mean the estimates are better. It means their methodology is HEAVILY padded, or if we assume +/-400~800%, they were just lucky that it didn't swing the other way. Given Phobos-Grunt, perhaps space engineering margin of error really is +/-400~800%. Although I suspect huge margins of error were thrown about in NASA>

Of course they padded their estimates and erred on the side of caution. 1) There is no way to retrieve or repair this rover. 2) NASA knew about the sticky dust from previous missions, but they didn't have omnipotence when it comes to the Mars climate. They didn't know that windstorms were capable of cleaning said dust. So you would have rather just wing it and not pad their estimates. So when the rover failed, they can tell NASA "oh well, try again in two years."

If that's the case, huge design buffers, that means they don't understand the underlying physics/materials engineer, and had to heavily overdesign, which means there is a far more efficient design out there.

I don't think you understand that there are different goals in engineering. One goal may be efficiency. The goal in this case was absolute reliability despite any unknowns the rovers may have experienced on Mars.

I'm not knocking NASA engineers, I'm just exploring how to shave down this margin so that they can make more efficient designs at lower cost that behave as expected.

Again efficiency is not as much a priority as reliability in these cases.

Building something that behaves as expected is far, far, FAR more important than building something that blows away expectations by orders of magnitude. The former is good engineering, the latter is waste, or worse, dumb luck!

The engineers never worked on the expectation that you ascribe. People outside of NASA have placed it on them. For them, the mission was successful when the rovers completed their objectives after 3 months. All these years afterwards are bonus.

Article misses the point (3, Insightful)

Anonymous Coward | more than 2 years ago | (#38843503)

The impressive aspect is not that it has operated for 8 years, or that it is "beyond its warranty" (which is a misnomer - there was no warranty). What is impressive is that it has operated in a harsh environment for 8 years WITH ZERO MAINTENANCE! None. No one has touched the device in over 8 years now. And it has continued to operate, by radio, despite dust, vibration, heat, cold and radiation beyond what most Earth-bound devices ever experience.

Sure, my car has well over 100K miles on it and is over 12 years old. But it is only operating because I am performing routine maintenance on the car. If I had not maintained the car, it would have stopped working ages ago. The impressive aspect of the Mars rover is that it has survived without anyone needs to tighten a nut, change oil, replace a battery or wheel or any of the routine operations that we have to use for our normal machines to keep them operational.

Re:Article misses the point (1)

iggymanz (596061) | more than 2 years ago | (#38843749)

not true, maintenance procedures including re-flash of Spirit's memory and software patch, that patch also applied to other rover as precaution.

Re:Article misses the point (1)

AdrianKemp (1988748) | more than 2 years ago | (#38843827)

In fairness (and not to diminish your point -- it is astonishing) there are several things on the rover that have pretty much bit the dust. They keep tweaking things to work around the breaking down hardware. Were the rover your car you'd have replaced a lot of it a long time ago because it's barely hobbling along.

That said, you're quite right it's an phenomenal achievement and the lessons learned will make/have made future missions even more amazing.

Re:Article misses the point (1)

DigiShaman (671371) | more than 2 years ago | (#38844747)

It's the constant thermal change that's effecting its life. 8 Years is nothing to scoff at. However, I am curious to know how many miles/kilometers this thing traveled in total. I doubt its as much as we think it is. This vehicle must rest in-between charge cycles I'm sure. Also, the #1 killer of any electro-mechanical device is moisture. Although the martian atmosphere is 100% saturated with water, it's so thin that its actually bone dry in comparisons with even the driest deserts here on Earth.

Wait a minute! (0)

Anonymous Coward | more than 2 years ago | (#38844099)

There's talk of the revival of the American automotive industry?!? Are there more bailouts or something?

Don't confuse NASA and JPL (1)

Squidlips (1206004) | more than 2 years ago | (#38844513)

NASA deserves little credit for the MER rovers (i.e. Spirt and Opportunity), in fact I suspect that the human-spaceflight ex-pilots at NASA/Houston would prefer to nuke all unmanned mission and dump (waste) all the funding on more manned pork. The MERs are JPL all the way. Do not confuse the money-pit, scientifically-impoverished manned missions of NASA with the low-code (comparatively), successful missions of JPL. Opportunity is one of the most successful missions ever flow, right up there with Voyager and Cassini. Compare that with the Shuttle...
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