2011-07-27

Spirit Sol 912

"Aren't you gone yet?"

That's Alicia Vaughan (nee Fallacaro), asking me the same question everyone else is asking me. It's enough to make me feel unloved, or at any rate it would be if they weren't asking when I was leaving for England.

Tomorrow.

Contrary to my hopes, we obviously won't be at Victoria before I hop the pond and lose touch with all this for a few weeks. Heck, we're not even to Beagle yet. Now I have to hope they don't get anywhere interesting until I get back.

It almost makes me want to sabotage thisol's sequences, just to give myself some extra margin ....

Heck, yestersol's sequence was nearly sabotaged for me. Yestersol's RAT calibration was undermodeled, so the IDD sequence cut off at the very end. It had taken the final image, but hadn't compressed the IDD data products yet. So we didn't get those. As a result, we don't have detailed current data, but we do have a visual OK and initial conditions, and that's good enough for us to proceed. So we'll clear the errors that resulted from the premature sequence cutoff and then continue down Rob's Yellow Brick Road.

We're off to see the wizard -- and I'm off to see some Shakespeare.

[Next post: sol 938 (Opportunity sol 919), August 23.]

2011-07-25

Opportunity Sol 890 (Spirit Sol 910)

The plan for the day is to drive on toward Beagle. First, we're going to repeat the unsatisfactory scuff done on sol 885, this time recording motor/IMU data at 8Hz to better characterize the rover's interaction with the terrain. We'll take juicy color PANCAMs of it -- or just get decent-quality HAZCAMs if we can't afford the PANCAMs -- and then we press on.

We're all fired up for driving, too. Tim Parker's "Victoria Goal Map" is showing us so damn close! We're only 85m from Beagle, and 561m from Victoria. I expect we should be able to do an easy 50m or so thisol, which would put us one drive away from Beagle and cut our distance to Victoria by about 10%. I am totally jazzed about this. We've got it all worked out, and we're raring to go.

That's why I'm so disappointed when the drive is cancelled. During the SOWG meeting, the science team decides the IDD data they've gotten at this location isn't quite high enough quality, and they need one more sol before driving on.

Bummer. But at least I get a good laugh out of Rob Sullivan's description of the now-irrelevant work we did on the scuff: "a fabulous exercise in futility."

[Next post: sol 912, July 27.]

2011-07-23

Spirit Sol 908

The plan for the day starts with two 7-deep MI stacks of ripples Spirit hasn't paid too much attention to yet. The stacks are 7 images deep rather than our usual 5 because they don't want us to disturb the soil by touching it with the MB first. This is the start of a longer campaign to get MI coverage of a strip all the way between the two ripples -- a strip I soon begin to call the "Yellow Brick Road," because Rob Sullivan indicates its position with a yellow line in a planning image. The two 7-stacks are all we can afford today, but there's more in our future.

So I have what I think is a clever idea: since we know where the best focus position is likely to be, why not take a gamble? If we did five 3-stacks along the whole Yellow Brick Road, centered where the best-focus position is likely to be, then one of two things would happen. Either we'd get the best-focus images all the way along, in which case we win big, or we get enough information to work out where the best-focus position definitely is, and we come back and do a single strip of images at that best-focus position later. Either way, it's many fewer images than the planned method, and we might even get done in a single day.

Turns out, though, that this is the wrong time for the creative approach. In this case, Rob actually wants the whole 7-stack, including the out-of-focus images, because the terrain has some relief that he wants to be able to study in detail. Best-focus in one image is out-of-focus in another in a case like this. So that brilliant idea is off the table -- this time. But maybe next time.

So we get started down the Yellow Brick Road. (In keeping with the theme, I naturally push for calling our intermediate targets "Dorothy" and "Tin Man." Whee, the fun we have!) As we go along, we keep in touch with Rob, who requested this observation and is now calling in from the road on the way to a family reunion. We get to reminiscing about the nominal mission, when Rob -- one of the few who was even more hard-core than I -- practically tried to stay up 24 hours a day for the whole thing. "I used to roll from rover to rover and just pass out on the floor in the MI room," he laughs. "Hey, we should gather pictures of everyone sleeping!"

Sometimes I kind of feel sorry for the new kids -- such as Antonio, who's shadowing today -- who missed out on the overwhelming fun and excitement of the nominal mission. But at the end of the day, I overhear him on his cell phone, excitedly telling his wife that today he wrote his first sequence for the rover. The bloom isn't off the rose yet.

[Next post: sol 910 (Opportunity sol 890), July 25.]

2011-07-11

Opportunity Sol 875 (Spirit Sol 896)

So close, oh, so close to Beagle. Less than a hundred meters now. But Mars isn't making it easy for us. Around Beagle, there seems to be an earthen (marsen?) rampart, a huge wall of impenetrable ripples. As far as we can see, north to south, the darn thing is just too tall to get over.

And if we just got over this one ripple, we'd have pretty smooth sailing all the way. On the other side lies the Beagle Highway, a sizable stretch of outcrop we could follow all the way in.

Yestersol, they tried the obvious approach: just power over this damn thing. It was risky, but they were careful -- still smarting from our recent experience in Jammerbugt, very careful -- and therefore sequenced quite conservatively.

And it was a good thing they did. We ended up getting partially buried in the ripple, almost as soon as we got fully onto it. But, because of the previous RPs' conservatism, we're not so badly buried that we can't simply back downslope.

Which is our plan for the day: just back away slowly. It's a short drive, but not a short day: as someone points out, discussion = 1/distance.

Before we go too far down, though, we're going to take advantage of the fact that we're about as high up as we're going to be for a bit: we'll snap some pictures of possible alternate routes to Beagle from this relatively high vantage point. We hope they show us something good, because we haven't got a whole lot of promising routes at this point.

By which I mean, obviously: we haven't got any. We're hoping the images will show us at least one.

Of course, there's always this option: just bypass Beagle altogether, get onto the sand sheet where we can move freely, then loop around and come at Beagle from the south instead. Rampart, schmampart: treat the giant ripple as a Maginot Line.

After we're pretty much done for the day, our old pal Jim Erickson stops by for a provocative discussion. "What tools would you want to have to drive the next generation of rovers?" he asks. I think he's just giving me an opportunity to plump for using RSVP on MSL, but he's after more than that.

So far, he points out, we've basically kept single drives within a known range of terrain types. When terrain types change significantly -- e.g., when Opportunity went from flat plains to the ripple terrain -- we've been able to adapt slowly, even to the point of uplinking new flight software to deal with the terrain changes. What he wants to know now is, how can we go beyond that? How would we have to go about driving a rover if a single drive might carry it across multiple terrain types, some of which we hadn't seen yet?

Hmmm ... now that's thinking big. I think we'd want some way to recognize and categorize terrain types, then have the rover switch to different strategies based on what type of terrain it thought it was in. We'd have a collection of strategies for known terrain types; for truly novel terrain types, it might have to go around or wait for help.

That implies a lot of changes to RSVP. Time to get to work.

[Next post: sol 908, July 23.]

2011-07-08

Spirit Sol 893

It's a fairly slow day. We're just carrying out some RAT diagnostics on Spirit, picking up the IDD and posing it for a few images of the RAT before putting the MB back where we found it.

Yawn.

The IDD work we're doing will take place on sol 893 -- the second sol of a two-sol plan. On sol 892, Spirit will simply nap pretty much all day. And it'll keep getting worse for another three weeks or so, until the winter solstice. Meanwhile, we don't seem to be putting as much data into flash as we can downlink. We can't afford to -- the science observations that would fill up flash are just too costly in terms of energy.

Spirit is a sleepy basset hound, snoozing on the front porch while flies buzz around her head. I plan to work her as hard as possible when we can. But for now, we'll let her get her rest. I hope she enjoys it.

[Next post: sol 896 (Opportunity sol 875), July 11.]