Debugging The Spirit Rover

icebike writes "eeTimes has a story on how the Mars Rover was essentially reprogrammed from millions of miles away. 'How do you diagnose an embedded system that has rendered itself unobservable? That was the riddle a Jet Propulsion Laboratory team had to solve when the Mars rover Spirit capped a successful landing on the Martian surface with a sequence of stunning images and then, darkness.' The outcome strikes me as an extremely Lucky Hack, and the rover could have just as likely been lost forever. Are there lessons here that we can use here on the third rock for recovery of our messed up machines which we manage from afar via ssh?"

Comments

Space Technology

[superpulpsicle]

That's the thing that amaze me. Any technology having to do with space seem that much more advanced.

Here on earth we can't even build cars that require no maintainance and last more than 10 years.

Re:Space Technology

[beeplet]

Actually any technology making it into space is more likely to be 10 years out of date... Getting anything certified for space is a long process. The technology in space isn't more advanced, just much better documented and well-understood.

Re:Space Technology

[kfg]

Ten years out of date, but ten years more reliable for the effort.

Sort of like Debian.

Cutting edge ain't always what it's cracked up to be.

KFG

Hindsight

[FTL]

The article (I know, I know, this is Slashdot) is really good. It contains everything that is missing from traditional media. The story, the background, technical details, and follow through.

Granted mainstream media have to keep their coverage dumbed down if Joe Public are going to read it. But what really bugs me is the lack of follow-up. We hear about poorly understood events as they are unfolding, then never heard about them later when they are completely understood.

A recent example is the gangway between ship and shore at the QM2's drydock. It collapsed killing lots of people, an investigation was launched. Why did it collapse? At the time it wasn't known. I'm sure it's known now, but there's been absolutely no followup.

This article about the rover is great not so much because of the level of detail but because it reports on an event with the benefit of hindsight.

Re:do they use SSH ?

[mcbridematt]

I don't think they would bother using anything to do with TCP. Anything you do send you will have to wait 9 minutes for. Just imagine the ping times:

Pinging mars-rover with 32 bytes of data:
request timed out
request timed out
request timed out
64 bytes from mars-rover: icmp_seq=0 ttl=64 time=32400ms :(

If it has anything to do with current internet protocols, it would be UDP.

Lucky Hack?

[electromaggot]

"The outcome strikes me as an extremely Lucky Hack..."

The outcome does not strike me as a "Lucky Hack." They made the system flexible, that flexibility got them into some trouble, and it's also what got them out of it. Anyone else agree?

Lucky Hack?

[SuperKendall]

Your post is the only thing that strikes me as a "Lucky Hack" here. They included the ability in the design to remotely disable booting from flash and upload new boot images, in what way is that a "hack"? All this is just foresight in design to include as many possible recovery modes as they could.

Basically, they rebooted from a recovery image (sent via radio) and then proceeded to do low-level fixes on Flash memory and they a chkdisk. If I do something similar via recovery disk or CD, I don't get a lot of people telling me that it was a "Lucky Hack" that I could boot off of CD!!!