Opportunity Sol 367 (Spirit Sol 388)

The good news is, there's a beautiful trench right in front of us, just where it should be. The bad news is, the scuff we made before trenching is unreachable.

They wanted to be able to hit four targets: the trench (wall and floor), the ripple crest, undisturbed soil next to the ripple, and the scuff. We got three out of four. Not nearly good enough. I feel lousy.

But one thing I've learned is that there's a time and a place for self-reproach, and the thick of ops ain't it. There will be plenty of time to beat myself up when we're done with thisol's sequencing.

And there's a lot of that to do. We're going to sequence two sols today, and two tomorrow, so we won't have to work Saturday. Thisol (367) we're going to MI the far wall of the trench, right at the boundary between trench and sky. The chosen area is a cross-section of the ripple, so we'll be able to tell what the ripples are made of. Then we place the MB in the trench, and later we switch from the MB to the APXS, doing an MI sky flat during the transition.

Nextersol (368) -- which we're also planning today -- we'll MI the trench floor, where we placed the MB and APXS, then MI the ripple crest and MB it.

Matt Golombek, the SOWG chair, wraps up the SOWG meeting. "That's a lot of work, and we're going to have just as much tomorrow. Anybody think we need to start before 8:30?"

"No," I say nonchalantly from behind him. My non-morning-person status is well known, so this provokes a laugh. But Matt accepts the suggestion, which emboldens me. "In fact, we could start at 9:30 or 10:00," I continue.

"We'll start at 8:30," Andy says, and that's that.

Frank brought some Japanese visitors to watch us at the SOWG meeting, and they're in the sequencing room when we get there. They're from Toshiba's space division, or something like that. They give me their business cards, and I give them mine. ("Domo," I say when they hand me their cards. "You speak Japanese?" the man asks in surprise. "Just a few words I've picked up in the dojo," I answer. I feel like a dumbass.) The woman actually looks at my card, and notices what's printed there. "Look!" she exclaims to the other guy. "It says 'Mars Rover Driver' on it!" They look at me with some mix of admiration and envy. I bet they wish their business cards said that!

We have about twice the normal workload today, so Jeff and I split it up -- I take 367, and he takes 368. Jeng hasn't done a lot of IDD work yet, and is trying to figure out which of us to watch. I'm almost done, so I suggest he watch Jeff -- that way, Jeng can see a sequence done from scratch.

But the more work I do on the sequence, the more I realize I'm not done after all. Since both vehicles have developed a problem with opening the APXS dust doors, we've been leaving them open for the last several months, and we have to be careful not to close them. (If we close the doors and can't open them again, the APXS becomes effectively useless. As a result, we lose much of our ability to determine the chemical makeup of rocks and soil, which would be a serious blow to our science capabilities.) There's not an explicit command for closing the APXS doors; you do it by rotating the turret almost all the way to one of its hardstops.

What I hadn't realized when first writing the sequence was that when I'm placing the MB in the trench, it's coming in at an angle that will rotate the turret to the point of closing the APXS doors.

Oh, shoot.

But this problem is masked for a while by another one: RSVP is reporting a collision error. Usually, this is due to one of two things -- either a self-collision, where the turret rotates through the forearm, or a collision between the IDD and the rover deck. But neither of those appears to be the case here. I'm puzzled until I think of turning on RSVP's collision-volume display, and then the problem pops out at me quickly. It thinks the arm is colliding with the wheel.

This seems ridiculous at first blush -- the IDD doesn't appear to be coming anywhere close to the wheel. But the collision volume for the wheels extends tens of centimeters above the normal settled position of wheels themselves, reflecting the fact that the front wheels can rise as the suspension articulates. At maximum extension, the IDD's elbow, of all things, grazes the top of the collision volume.

Working around this requires some care, but it's not bad. We have macros to turn the wheel collision volume on and off, thus automating the really hard part.

All told, it ends up taking several hours to work through these problems. Good thing I was almost finished several hours ago, or I wouldn't have gotten done at all.


Jeff and Jeng are finishing up about the same time I am. We're late, but we're not the ones holding up the process -- the TULs and TAP/SIEs have been working through a variety of tool problems. But we're on the critical path now; uplink is in just a couple of hours. And we're not finished -- at least, we haven't taken the critical step of reviewing each others' sequences.

"You've got no margin on the walkthrough," Julie warns us. "And you have to deliver right after." So we're going to have to get this right.

Jeff and I swap off and review each other's work. Either we're both idiots or both brilliant, because neither of us finds a significant problem in the other's work. Despite our needing to change the sol-367 MI target at the very, very, very last minute, we're ready for the walkthrough ten minutes early, which is like gold in the hand at this point.

So we start the walkthrough ten minutes early, and it goes well, and then for us RPs it's all over but the shouting. At this point, we mainly have to wait for the TAP/SIEs to turn the crank. We take a few minutes for a post-mortem.

"So was that too hard?" Golombek asks. Jeff says he feels like it was just about right, but I don't -- I don't really feel like we had enough time to review each other's work. Maybe we can do it better tomorrow, since tomorrow will be much like today.

"You know, today reminded me of nothing so much as a primary mission sol," Julie observes. "It was that crazy, things changing that much."

"But if you think about it, we're about four times as good as we used to be," I point out. "We just did two sols, in about half the time it used to take us to do one."

"Better than that," Andy adds. "We're doing it with fewer people now."

As the conversation inevitably digresses, Andy relates an amusing tidbit. MRO wants our (Opportunity's) sequencing room. Their idea is that Opportunity would move downstairs, into the now largely unoccupied science meeting room.[1]

But the sequencing rooms have special facilities requirements, what with all the videoconferencing equipment and such. This makes a move unusually expensive, and MRO can't pay for it. Not because they don't have enough money, but because it isn't distributed properly -- unless they want to violate their contract with NASA (and believe me, they don't!), they don't have a budget category that would enable them to pay for the move. And MER won't, or can't, pay for it. So we get to stay here. Saved by the budget.

Uplink's at 17:30. We finish the CAM at 18:40, 50 minutes to spare.[2] It's hardly even dramatic.

I bet we could have sequenced one more MI stack ....


[1] Instead, this became a MER cubicle farm. We still have that sequencing room.

[2] It was obviously a long day, because my original notes are plainly wrong here. Clearly, one of these times is off by two hours: either uplink was at 19:30 and we finished at 18:40, or uplink was at 17:30 and we finished at 16:40. At the remove of five years, I'm not sure how to find out which it was, so you'll probably have to struggle through your life bearing the uncertainty.

1 comment:

Anonymous said...

re "The woman actually looks at my card" -- if memory serves, it's actually pretty rude in the Japanese culture to receive a card and not actually look at it.