Spirit Sol 503

When I arrive we're having problems with the OSS, the network filesystem that we use for, well, pretty much everything related to uplink and downlink. One effect of this is that SAP hangs at startup, so the scientists can't do their science planning. Mark Powell, one of the SAP developers, is scrambling for a fix, but he doesn't seem to be having much luck.

Meanwhile, Steve reveals that he and Dave DesMarais have been going over the science results and have concluded that it's time to move on. We've going to finish up IDD work in this location thisol, then drive back to Methuselah and on around to the south side of Husband Hill toward the South Basin. This will take us uphill, though possibly not to the summit. We'll have to see. I'll be back on Opportunity before much longer, anyway, so the struggle to reach the summit will be someone else's for a while.

Mark has just about given up. I decide I should try to help him. I suggest setting up a temporary OSS under somebody's home directory -- all they need is a file structure, and SAP can be given the root of that structure at startup. He looks startled. "Worth a try," he shrugs. A few minutes later he has this working, and Alicia Fallacaro is whipping up a science plan. She beams gratefully at me. "Scott saves the day!" she says.

When I see the IDD target they want to poke at, I almost regret helping them get up and running. The target -- "Nantucket," continuing the Moby Dick theme -- is in a particularly awkward region of the IDD work volume, tight up against the left front quarter of the rover itself. I muse aloud that during the nominal mission this would have freaked me out, which seems to surprise Al Herrera. "I thought you were always cool, calm, and collected," he says. "That's because you only see the back of my head," I tell him. "If there were a mirror set up on the monitor so you could see my face, you'd know better." I'm only half kidding.

Nantucket's a real bitch of a target for a 2x2 MI preceded by a MB touch. There's almost no room to switch from the MB to the MI, for one thing; for another thing, the IDD really wants to collide with itself as we move between the stacks. I find a way to make it work, but the tolerances are so tight that Chris has a heart attack when he looks at it. We show Squyres, who decides to split the MI work -- half on Nantucket, half on a nearby rock we call "Starbuck." We use an MB-touch on Starbuck, since it's far enough away for us to do this comfortably. On Nantucket, we'll just use a less reliable MI poke, which will save us from having to do the tool change. (Poking a rock with the MI is enough like harpooning a whale that we should have named this target after one of the Pequod's harpooners. "Queequeg" was already taken, but we could have named it "Tashtego" or "Daggoo." Ah, well.)

While I've been working on this complex IDD sequence, Chris has been cranking out a comparably difficult drive. I don't like sols like these, just because we don't really get enough time to review each other's work, and that bites us this time. At the CAM, at the very last moment, I realize that we made a mistake: we do some visodom, then some blind driving, then some autonav -- but we forgot to clear the nav map between the blind and autonav segments. This means the rover will have an inaccurate picture of the world around it -- potentially a dangerously inaccurate picture, since it could drive over ground it thought was safe but was in fact host to a deadly obstacle.

So we need to rebundle. All I need to do is insert a single command that tells the rover to clear the nav map before the autonav segment of the drive, but here I make another mistake: Jim Erickson asks whether that's really all we need to do, and I reply with insufficient authority in my voice. He starts to look nervous, and though I realize my mistake, it's too late now. There's no help for it but to call another expert.

Mark Maimone's in China, and all of Jeff Biesiadecki's contact numbers lead to voice mail. Fortunately, Khaled did some testing of exactly such situations in the testbed, and I'm able to reach him. So his vote plus mine makes Jim look happy again -- well, as happy as he ever looks -- and we commit to the change.

[Next post: sol 509, June 8.]

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