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Mars Phoenix Lander's Ovens Were Destined To Fail
RobertB-DC writes "The Phoenix mission to Mars' frigid polar regions was going to be tricky from the start, with only a few weeks to perform as much science as possible. Success depended on everything working right. But one of the mission's most frustrating glitches — the stuck doors on the TEGA ovens — could have been prevented with basic quality control on Earth. Nature is reporting that bad brackets were replaced by the manufacturer ... with identically bad brackets. The Planetary Society blog sums it up succinctly: 'Ouch. Ouch ouch ouch.'"
This is what happens when too many people have their hands up the engineers and by extension the technicians' asses.
An Education is the Font of All Liberty
Aren't they covered by warranty ? Get them to replace them.
May contain traces of nut.
Made from the freshest electrons.
Ovens?
Sounds like too many cooks were involved.
...isn't this what happens when you gotta have it yesterday?
One more thing to add to my list why humans should be involved in space exploration, not just robots.. Perhaps this could be fixed if there was a human there?!
From the blog:
Boynton and his team had noticed, on a test version of TEGA, that the brackets at the bottom of this cover were just a hair's width too big, and as a result obstructed the doors. They sent revised designs for the cover to the manufacturer, Honeybee Robotics of New York. New parts were delivered and installed. But Honeybee had made the new parts using the original flawed designs -- and nobody in Tucson checked them. "They should've caught it and we should've caught it, but neither of us did," says Boynton, ruefully.
. . . which is why NASA needs to hire my mother as oven test engineer. Not only would she have noticed "hair's width" difference, she would have taken every opportunity she had to complain to everyone she knows, and even total strangers about it.
On the other hand, once the door problem got fixed, she would find something else wrong with it, and the damn thing would probably never get off the ground.
Schroedinger's Brexit: The UK is both in and out of the EU at the same time!
You are forgetting something ...
Some plans for a manned Mars mission were based on there not being a return trip to Earth. Anyone who went on such a mission would be marooned there on purpose. It's not a kind of trip I would like to take.
``Nature is reporting that bad brackets were replaced by the manufacturer... with identically bad brackets.''
Isn't that just purely amazing? A manufacturer who _knows_ the component is bad (because it needs replacement), and then replaces it with ... the same thing with the same faults. That's just unethical. I hope they are suitably punished.
Also, you would have thought that, after sending a component back for replacement, the replacement would be tested to see if the problem had been fixed.
I just don't have words anymore.
Please correct me if I got my facts wrong.
Off-topic, and the author is an idiot. The rovers' cameras do not necessarily take pictures using the standard red-green-blue colors that we perceive. Depending on what filters were used (for scientific reasons), if you want a "full color" image for humans to appreciate, you have to choose or synthesize non-RGB channels to form an RGB image. The blue tab, for example, on the color calibration target is also very bright in the infrared, so if you use an infrared image as your red channel, what should be blue appears to be pink. All of this perfectly normal and completely expected by everyone that knows how this stuff works. Stop being a silly conspiracy theorist and apply some rational thought and a tiny bit of research.
http://www.badastronomy.com/bad/misc/hoagland/mars_colors.html
http://marsrovers.jpl.nasa.gov/spotlight/spirit/a12_20040128.html
Everything needs a version number and serial number.
Maybe it was the Martian government trying to protect local jobs from foreign workers.
Some of what I say is fact, some is conjecture, the rest I'm just blowing out my ass...you guess.
Most of the comments so far are focusing on the oven door problems. Naturally, because that's what's mentioned in the summary and no one RTFAs.
Anyway, the *much* more interesting revelation is that after the problems came up, the directive came all the way down from the top of NASA directing the mission scientists to change their plans. "At the end of June, word came down that the Phoenix team was to treat its next TEGA sample as its last, and to go after a sample of rock-hard ice before it did anything else. The Tucson team had lost its autonomy." After that, the team blew at least a month trying to meet this directive, and missed out on doing some of the basic science they wanted to do, just so NASA heads could trumpet feel-good publicity about having detected ice with Phoenix.
Yes, it is a horrible engineering. However these are one-off designs that never existed before and will never exist after. There is no legacy to build upon, and there is no "Release 1" to learn from. The very first release flies the mission, and if there are bugz ... too bad. To confound the problem, much of this work is probably done by scientists and not by engineers; that's why if the gap between doors is above zero it's all good to go. An experienced mechanical engineer would consider thermal expansion, free play in all pivot points, and other things - but first she'd try to increase the gap to some reasonable size, so that none of those secondary effects could affect the mission.