2009-12-07

Opportunity Sol 310 (Spirit Sol 331)

We're not driving thisol, which is as expected. But we might not drive nextersol either, since the RAT hole we dug over the weekend didn't go very deep. (Ray deems it a "wussy grind.") On a steep slope like this one, we can't push the arm very hard against the surface, so when the RAT encounters resistance, it's very easy for the IDD to skip off. That causes the RAT to sense it's lost contact and stop drilling, and it seems to be what happened this weekend.

If the RAT folks can verify that's what happened, we'll basically redo that work tomorrow. If they can't, then we'll bag it and drive tomorrow instead. Jeff has his fingers crossed; he's already got the egress drive planned out. But as the SOWG meeting ends, the RAT team reports that they can confirm the cause of the wussy grind, and according to them, it's safe to re-grind. "Sorry, Jeff," I mutter, and he shrugs.

Jeff's been here since just after he dropped his kids off at school this morning, and it's now already past 13:00. So he's been a busy beaver; not only has he planned the egress drive, he's also done most of thisol's IDD sequences. Thanks to that, it's another easy day.

Since I can always stand some easy days to balance out the hard ones, that's good news. But there's even better news: Spirit's right front wheel seems to have healed itself.[1] Its current draw has been nominal for some time. So there's no longer a need to drag it, as far as we know, and driving Spirit can become simple again. There are a few, easy-to-honor restrictions, which basically amount to "don't drive it so hard."

"Earth, Earth," says the Mars rover, "it hurts when I go like this." And then the Earth says, "So don't go like that."




Footnotes:

[1] Long before Spirit's right front wheel failed entirely, it was exhibiting a worrisomely high current draw. This manifested itself during her sprint across the plains toward Husband Hill. We'd dealt with it, in part, by employing a 90/10 duty cycle -- drag the wheel for 90cm, then run it for 10cm, which lifted it over the pile of soil you'd build up during the dragging part. This was a real pain to deal with, and it was nice to be free from it for a while.

1 comment:

Anonymous said...

Could you please do something to make it much more obvious that newly posted material is many years old? I suppose I should have realized that sols circa 300 were far distant sols, but the medium, a blog, and the title that includes "diary", and the present tense, all made me expect that it was current events I was reading.

It's really good historical stuff, it's just very poorly described.

Thanks