Mars Rover Recovering From Memory Problems

New Scientist ^ | 1-28-2004 | David L Chandler

[DMCA]

1 Astronomical Unit = 8.31675359 light minutes

Mars is, at its furthest point, 2.5 AU from earth leading to a one way trip time of 20.791884 light minutes.

[thesummerwind]

Mars Rover Recovering From Memory Problems

Damn, I can't even remember last night.

Did anyone see Dennis Miller's second show? If so, give me some stuff!

[ambrose]

When all else fails, CTRL ALT DELETE...

[r9etb]

No, the explaination is not reasonable, but troubling. The rovers were designed to last 90 days, (and travel 8 months). The longest test was 9 days! NASA is still infested by "faster, cheaper". I can't even imagine who would be dumb enough to let these guys send them to Mars!

The underlying problem here is that they didn't do a realistic loading test. They obviously demonstrated some basic capabilities, but didn't do enough uploads to create the problems seen.

This is a systems engineering/test planning problem -- probably nobody even thought of doing such a test.

In hindsight we can point fingers, but of all the problems that could have happened (which would have driven the Failure Modes and Effects Analysis that in turn drove the test plan), I can really understand them not having thought of it.

I think this will probably join the annals of "Learned the Hard Way" lessons, and folks will do that test from now on. I know I'm gonna use this as an example for the students in my class.

[r9etb]

Glad to have somebody to agree with.... ;-)

[John H K]

There actually never was any "NASA Glory Era" where everything worked perfectly.

We had launch vehicles blowing up left and right in the early 60s. The Apollo I ground test killed 3 people. We almost lost Apollo 13.

And we've consistently done better than everyone else. The Soviets had an obscene number of Venus and Mars probes fail. The Japanese just had theirs fail. Beagle 2 failed.

Not that better performance shouldn't be demanded and expected but there's a limit to how perfectly reliable all of this is going to be.

[BigWaveBetty]

Stuff on Freepmail.

[BigWaveBetty]

Nice picture, but it gives rise to a few questions: For example; Why did they send a wood burning stove and where are they going to find the logs?

Ha! It does look like a wood burning stove. Those dang scientists prolly stuck some wheels on one, shot it into space and then charged us a billion for it! ;-)

[6ppc]

why couldn't the number of files storable on a given memory be a SW configurable parameter upon reset?

It has to do with the data type used to store the data, for example a byte (8 bits) is limited to storing numbers between -127 and +128, or 0 to 255 with no sign.

[brownsfan]

There actually never was any "NASA Glory Era" where everything worked perfectly.

I agree. Our memories trick us. It *seems* they were better then they were. Although, they were amazing given what they had to work with. And, that is where the expectation/criticism comes into play. NASA has better tools, and better background. So, personally, I just expect more.

[Lessismore]

Flash File System Selection Guide from Intel.

http://www.intel.com/design/flcomp/support/applnots/29766505.pdf

Wind River seems to use TrueFFS from M-Systems. Elsewhere, this has a configurable maximum number of open files. It can provide FAT if the operating system doesn't provide the File System layer above TrueFFS.

[Fitzcarraldo]

Recovering Spirit Sends a New Picture

NASA's Mars Exploration Rover Spirit took and returned this image on January 28, 2004, the first picture from Spirit since problems with communications began a week earlier. The image from the rover's front hazard identification camera shows the robotic arm extended to the rock called Adirondack. As it had been instructed a week earlier, the Moessbauer spectrometer, an instrument for identifying the minerals in rocks and soils, is still placed against the rock. Engineers are working to restore Spirit to working order so that the rover can resume the scientific exploration of its landing area.

[GretchenEE]

marker bump

[GretchenEE]

What is bleeding-edge technology?

Where's your .gif / .jpg / .bmp? I hardly recognized you!

[Nick Danger]

What is bleeding-edge technology?

That's the stuff where, when it works as planned, you say, "Hey! We got lucky!"

OK, here's the plan. We're gonna make this machine, and we're gonna shoot it to Mars, and just before it hits the ground going a hundred miles an hour, these air bags are gonna inflate in the nick of time just like in a car crash, and our little car is going to crash into Mars. And the air bag is going to save it. And then we'll deflate the air bag, the thing will fall a couple feet to the ground, and then it's gonna roll around and take pictures and send them back to us.

When that actually works, all you can think is, "Just damn!"

[GretchenEE]

Thanks for the explanation. And the poetic way to describe it.

Li'l ol' Spirit is a marvel.

It's reassuring to see your face with your post. ;-)