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Mars Rovers Have Incorrect Instruments Installed
Christopher Reimer writes "The New Scientist is reporting that the twin Mars rovers, Opportunity and Spirit, has instruments installed in the wrong rovers. From the article: 'While the bungle does not undermine the main scientific conclusions drawn from the data collected by the rovers, it is an embarrassing slip-up for a space agency that once lost a Mars spacecraft because engineers mixed up metric and imperial units.'"
Who knew being a rocket scientist was so tough.
Twin Mars rovers, Opportunity and Spirit landed on the Moon.
Subject says it all - mod me down if you have never read Mark Twain :)
"Love is like pi - natural, irrational, and very important." (Lisa Hoffman)
They instruments were installed correctly on Earth. It's the Martians that switched them as a prank. :-)
It annoys me that so much is made of this problem. This in no way compares to the lost spacecraft error, it's simply a calibration adjustment to a sensor. I think the fact that they have two rovers that have performed extremely well under harsh conditions 4x over their rated life is an incredible accomplishment. This just sounds like someone looking for sensationalism in a non-issue.
To clarify the summary: it's not that the WRONG instruments were installed, but that the SAME instruments were installed but calibrated for the OPPOSITE rovers. So, the data have been slightly off in a predictable way. In the end, it's not too surprising nor is it devastating. The data is still valid and is being readjusted.
Why is it hard to support them when they're in the middle of a hugely successful Mars mission?
No one outside the community even noticed this until recently, and in the end it really made no difference. So where's the beef?
Even though the designs of the rovers are identical, the instruments themselves are not. The article says so. Each instrument was calibrated to behave properly in one rover. When the instruments were swapped, the readings from them were incorrect.
StrayByte.Net
How can i possibly advocate for a mars mission when they can't even get this shit right?
How can I possibly listen to you when you cant even used the shift key properly.
Moneyed corporations, non-working 'poor' and criminal prisoners are turning productive citizens into tax-slaves.
They're the same device on each machine, with the same function. The only problem has been that the data received has been interpreted with the wrong calibration adjustments. Swap the calibration adjustments and rerun the data, and it'll be correct.
It would have been far worse if, say, one had a spectroscope and the other had a *drill*, and they were swapped, and each rover couldn't use the other's tool. And in that kind of a switch, it would be really bad, because the two devices would be visually distinct. But the swapping of two devices that are 99.99% identical, on two rovers that are identical, is no big thing.
Compared to the fact that the rovers are still running long after they were expected to die, this is a tiny, tiny thing.
September 2011: Looking for Cocoa/iOS work in Boston area Cocoa Programmer Quincy, MA
At least they landed 'em on the right planet.
OK, now what?
While the lead scientist says that it wasn't a big deal and no investigation will be held, I think he isn't analyzing the significance of this event. While scientists are more focused on the validity of data, engineers have to analyze not just events that occur (like loss of a rover), but also events that could occur. Putting the wrong instrument into a rover is due to "failure to follow procedure". This is a big deal. Failure to follow procedures could have been caught by a better QA system, better monitoring of the installation, and better training (including walkthroughs on the installation of the instruments).
Even though this minor event that has had no impact on the mission, it has shown that there are holes in JPL's QA system, their monitoring system, and their training program for building these rovers. If you want to dig further you might find that all of these problems were caused by an unnecessary sense of urgency which may have been caused by poor project planning. These exact problems have caused the loss of spacecraft before (and many of them were cited for the loss of Challenger and Columbia).
No investigation? The lead scientist really needs to take a look at his project management priorities. Having experience working in nuclear power I have learned and have been trained that small problems are many times the only symptoms of much larger problems. The lead scientist's attitude on the problem gives me no confidence in his ability to run a more complicated mission. Like in gambling, one or two successes doesn't mean that you are going to win on the next roll.
Suddenly, the hairy finger of a familiar monkey tapped me on the shoulder. It was time.--G. T.
Let the New Scientist criticize from the cheap seats. It is hard to argue that the rovers have been anything other than a resounding success for over 400 days. I would have hoped /. would
instead print the recent story of the Spirit Rover
discovering
salty soil.
an ill wind that blows no good
"There was a point when both of them were sitting on the same bench, and that has to have been it."
Wouldn't they have been labeled, what does this have to do with anything?
From the JPL website: "Meanwhile, scientists are re-calibrating data from both rovers' alpha particle X-ray spectrometers. These instruments are used to assess targets' elemental composition. The sensor heads for the two instruments were switched before launch. Therefore, data that Opportunity's spectrometer has collected have been analyzed using calibration files for Spirit's, and vice-versa. Fortunately, because the sensor heads are nearly identical, the effect on the elemental abundances determined by the instruments was very small. The scientists have taken this opportunity to go back and review the results for the mission so far and re-compute using correct calibration files. "The effect in all cases was less than the uncertainties in results, so none of our science conclusions are affected," Squyres said." It would have been more serious if they had lost the calibrations on the instruments.
I've got your sig, right here.
one word: Tolerances.
when you have 100 resistors at 0.5% tolerance, you are gonna have drift, and you will have to calibrate them to the right parts, you can make 100's of those cars of the same make and model, but none will be exactly the same, especially when you have sensitive equipment. (Think odometer)
>once lost a Mars spacecraft because engineers mixed up metric and imperial units.
I'm getting pretty tired of this sound (text?) bite the media throws out. It wasn't mixed up units; it was error accumulation from switching back and forth between the units.
So, let me get this straight: NASA has managed to successfully send two completely functional rovers to the planet Mars 45 million miles away. Since they have arrived, the two rovers have expanded our understanding of the planet greatly and have had few and mostly correctable errors. They are now way, way past their expected mission time and are still running, and a few people have the nerve around to here to bash NASA for their horrible, numerous mistakes?
This stuff isn't easy. Just because you reap the benefits of the entire space program from your living room couch via the TV without actually contributing one bit does not mean you have any understanding of how complex and spectacular these great accomplishments are.
To the NASA / JPL engineers and scientists: Thanks.
Damn your Dumb! Read before posting dumb things. No two things are exactly the same even if designed as such. And yes you can get in two identical cars and one will perform different.
It's a calibration, the whole concept is no two things are the same. Any piece of instrumentation needs to be calibrated and that calibration is set for that device. No manufacturing can produce 2 identical things, just not possible since the two items could not share the same time and space in the universe together thus both are going to be slightly different.
Anytime you get a piece of gear, you get it setup, then you take some means of calibrating it and test it with something that has deemed to be as accurate as possible. Maybe some source such as a rock. But basically anything that will provide a common test basis for the device.
So say you are measuring temperatures on something in a lab. You set up a big system for collecting data off a bunch of thermocouples. Each one has it's own channel through it's own voltage modules and thermocouples and so forth. So you take a calibrator and have it feed a signal through the system to mimic a thermocouple. you get a calibration curve for a channel, then you go to the next channel with the same device and do the same for the next channel, this will be a different calibration. and then you work through them all. I have system set up with 16 channels at work and all use the same parts, but there is about 4 closely similar calibrations across the channels, but no two channels follow the same calibration.
NASA did the same, they built the devices, then calibrated them with the same rocks, and developed a calibration curve for each system, and that was to be kept with each rover, they swapped the instruments, so now they switch the calibrations and everything is fine.
This all goes back to simple accuracy and how close you can get things, but bottom line no two things are the same. Look at computers, you can have 100 computers, exactly the same built right in a row, with the exact same software and so forth. Turn them on and let the run under exact same conditions, some will have hardware failures, some will have software get wacky on them and so forth. It's just the way it works.
RTFA. NASA swapped the instruments inadvertently but since both the rovers and the detectors are manufactured identically the only consequence was that we were using the calibration data file from one instrument to analyze the data coming from the other. Swap the calibration files so they are coupled to the correct instruments again, reanalyze the raw data, and the problem is solved without having to privatize NASA.
How can i possibly advocate for a mars mission when they can't even get this shit right?
The Mars mission is stupid but not for the reason you give.
A hermit writes: "The Church is reporting that the two human genders, male and female, have instruments installed in the wrong genders. From the article: 'While the bungle does not undermine the main reproductive conclusions from the reproductive activities between genders, it is an embarrassing slip-up for a supreme being that once lost a world of worshippers to a flood because the first prototypes mixed up good and evil.'"
Sometimes I wish I was a plumber, then I'd know how to deal with other people's shit.
No manufacturing can produce 2 identical things, just not possible since the two items could not share the same time and space in the universe together thus both are going to be slightly different.
Oh, come on! It's easy!
ln rover_1 rover_2
See?
Then ask yourself how many times identical twins that you've known managed to play some trick on you.
And can we tone down the headline sensationalism a bit? You'd think the rovers have a core drill where there should be a camera or something. They somehow managed to switch two spectrometers, as identical as modern metallurgy can make them, destined for two similarly identical rovers - and now the error's been uncovered and the data recomputed. Jeesh...
Right, a Post-It. On a spacecraft to Mars? These are highly sensitive one of a kind instruments. You don't just go sticking paper and glue all over it.
Post-Its are not static dissipative. You could have a static discharge damage components and you wouldn't even know until the rover had landed on Mars. You could accidently leave a Post-It on the spacecraft and cause damage. How do you know residue from the glue on the Post-It won't cause damage? Now you have to test for that. It is amazing how one stupid thing like a Post-It note could add more complexity and make things even worse.
Now what would have been smart is to have devices like this keyed so that they can't possible be installed in the wrong place. But that tends to add complexity to the design and when you are only building a handful of rovers in highly controlled conditions, it can be hard to justify.
What is stupid is that there is no investigation of what happened. Sure, in this case the mixup was relatively harmless, but the next one might not be. NASA needs to be more proactive and not wait until things blow up to have an investigation. I don't expect perfection, but they at least have to understand their flaws.
Because they're rovers,
Identical rovers, you will find...
They look alike, they rove alike,
They even calibrate alike!
(Should I put this alpha-particle X-ray spectrometer in you...or you? Whoooaaaa!)
You will lose your mind!
When rovers...are two of a kind!
Identical Rovers! Tuesdays at 8 on SCTV!
Once the mistake was realized, they could easily accomodate it through other calibration techniques. I think the parent article is trying to raise a sandstorm in an otherwise rarefied atmosphere.
...put Burt Rutan in charge of the mission.
This was a follow up mission to the Viking landers which found no signs of life on Earth.
Damn your Dumb
"you're".
you get it setup
"set up". ("setup" is a noun.)
something that has deemed to be
"has been deemed".
Each one has it's own channel through it's own voltage modules
"its" (both places).
but there is about 4 closely similar calibrations
"there are about".
Had either of the Mars Rovers crashed or broken in some way, this mistake would never have been discovered. With only 1 rover's data, there would be no mysterious discrepency to solve and this mistake would have never been resolved.
So scientists would have spent the next 10 years developing their theories of martian geology based on incorrect data if either one of those rovers hadn't deployed and you call this a minor issue?!
This kind of error is inexcusable. But of course, it'll get brushed over because NASA was lucky enough to be in a position to fix it.
...and it proceeded to install those instuments all over the surface of mars.
Spirit and Opportunity have performed incredibly well. These guys deserve nothing but respect.
You know, Compared to mixing up metric and imperial units, this seems downright intelligent of them.
Okay, I was in the meeting where the difference in calibration was discussed, and I was the one that suggested that the instrument packages should be marked so that the right package would be installed in the right lander.
I recommended that one package should be marked with an "O" for "Spirit" and the other with an "S" for "Opportunity". I even donated the Sharpie marker and masking tape for this purpose.
It's not my fault that the implementation was screwed up. It's those numbnuts in the Vehicle Assembly Department who can't read a bloody memo.
Fortunately, I've left NASA for a position at the Department of Defense. My team is tasked with identifying sites related to the constructon of weapons of mass destrucion in South Korea.
k.
"In spite of everything, I still believe that people are really good at heart." - Anne Frank
"On September 27, 1999, the operations navigation team consulted with the spacecraft engineers to discuss navigation discrepancies regarding velocity change (V) modeling issues. On September 29, 1999, it was discovered that the small forces V's reported by the spacecraft engineers for use in orbit determination solutions was low by a factor of 4.45 (1 pound force=4.45 Newtons) because the impulse bit data contained in the AMD file was delivered in lb-sec instead of the specified and expected units of Newton-sec."
My journal. Mainly about freedom.
... a rocket scientist isn't what it used to be.
If someone says he and his monkey have nothing to hide, they almost certainly do.