Spirit Sol 167

One of the many things that's been great about being a rover driver is: no meetings.

Actually, we have meetings all day long -- the downlink assessment meeting, the SOWG meeting, the activity plan approval meeting, the command approval meeting -- but unlike most meetings, these are useful, necessary, productive, and focused. Also, they're exactly as long as they need to be -- no shorter, but no longer. And we skip the ones we don't need on any given sol (this is rare, but it's happened). If all meetings were like that, I wouldn't mind them at all.

Today I get invited to three meetings, all to be scheduled this week. First, Rick Welch wants me to attend a meeting to discuss the rovers' slip in the current terrain; this is preparatory work for climbing the hills. Second, Jake Matijevic wants to have what is apparently a different meeting on the same subject. (Maybe they're the same meeting, but it doesn't sound like it.) And Justin Maki wants to have a meeting about the terrain-mesh problem, where we've twice discovered the ground wasn't where the telemetry said it was.

It was nice while it lasted.

Ah well, this is all stuff that has to be done. And because there's usually a rover planner on shift at any given time when these meetings might be held, it's tough to get more than three of the four Spirit rover planners together for any given meeting. Maybe I'll be the lucky one. (Hmm, let's see -- drive the rover, or go to a meeting ... drive the rover, or go to a meeting ....)

The sol-163 sequence -- the last one I was here for -- seems to have gone perfectly. (Ray was right.) Since then, they drove away from the rock, and then drove back to it, trying to get a better angle for RATting. Unfortunately, we're in new terrain -- soft stuff under the wheels, and at a sharp angle -- and we're slipping like crazy. So they've spent three sols driving away and trying to drive back, and we're still not done; we've got yet another short drive in the plan for thisol, and we expect to have to complete the job nextersol. (Thisol we're climbing up the last part of a ridge, and the target is on top. We have slip data that show what happens as we try to climb at a given angle, but we don't have data to show what happens as we climb over an edge, as we're doing in this drive. It's anyone's guess.) Annoyingly, it turns out that there was a RAT solution in our original orientation after all -- we didn't have to drive away from the rock in the first place.

Since we're having so much trouble with this drive, and we expect similar trouble driving up and down the hills, John decides we should experiment with visual odometry. Visodom has displayed a few bugs on Opportunity recently, so we don't want to use it in actual rover-driving mode, but we could at least run it in a data collection mode, to try to get a sense of how it will work for us. I fetch Mark Maimone, and he shows me and John what we need to do to use visodom in this sequence. We put in all the commands we need, then find out there's not nearly enough time in the plan, so we have to rip it all back out. We do manage to sequence some NAVCAM images during the drive; Mark can process these on the ground and see what the rover would have done with them, so it's not a total loss. But this is at least the third time we've hauled Mark in as an expert in order to sequence visodom for Spirit, only to recant. Mark takes it in good humor, though. "This is becoming Xeno's visodom testing," I say, and he grins ruefully.

Thisol is a touch-and-go: we're unstowing the IDD, taking measurements of a soil patch dubbed "Jaws," then driving on. We're commanding the rover to drive about 2.2m, and expect it to cover about 1m due to slip. We'll have to see what it actually does, and I make sure to warn the team that we may need yet another sol to get into position to use the RAT on PotOfGold. Larry Soderblom quips, "So tomorrow, it's either RATs, or 'Rats!'"

But later he (unknowingly) echoes Ray's prediction from a few sols back. "I have this feeling it's going to work," he says.