The crater triplet is called Trieste. Which is in Italy. So why are the target names French? (And one's misspelled, at that: "Flinders" instead of "Flanders.") Beats me.
Matt was right, this area makes for a hell of a picture. Once we're into sequencing, I load up a section of the NAVCAM panorama covering the crater in front of us and the one beyond, and switch into 3-D mode. Doing this usually draws people to the workstation, and this time's no exception. One by one, the team members slap on a pair of 3-D goggles and stare in amazement at this inspiring sight.
I don't have much to do -- we turn for comm on sol 389, and then on 390 we turn back and descend about 70cm into the crater to get a patch of flat white rocks in our IDD work volume, so we can poke at 'em next week. Then they take out the comm turn (after I've sequenced it), so I guess that's one less thing.
I knew I'd be working with Jeff thisol, and he's conservative enough to be very nervous about entering the crater at all. So I applied a lesson from aikido: get into position. Last night I spent a couple of hours manually settling the rover to get a sense of exactly where it would end up when we bump forward. RSVP normally automates terrain settling, but that doesn't work in this case because we don't have terrain under the rover, and the software lacks common sense to tell it what unknown parts of the world look like. "Manual settling" means manually tweaking the modeled rover's position, attitude, and suspension until it's in a plausible configuration, perched realistically on the terrain. It's like a Rubik's cube: solving one part of the puzzle tends to disrupt your solution for the other parts, so you have to solve them all at the same time.
But I end up with a pretty reasonable picture, with the rover pitched about 7.5 degrees, and with an overall tilt of about 8.2 degrees. Figuring I'm wrong about some aspects of the solution, our final tilt might be as bad as 10 degrees. That's a bit high for soft sand, but not too bad; and the rear four wheels are all on level ground beyond the crater rim, which helps. I show the solution to Jeff, and most of his nervousness evaporates rapidly. Score one for aikido!
Justin Maki's been up to something characteristically ingenious, and today he shows it to me. It's an orbital map of our location, in the form of a terrain mesh we can load into RSVP. You can zoom way out -- and I mean way, way, way out -- and see the whole area around us, for kilometers in any direction. Just as a test, I go ahead and sequence a candidate drive to Vostok. With this new mesh, it takes no time at all. Then I do the 4.5km from Vostok to Victoria. This is going to be a hell of a good tool for these insanely long drives we've been planning. I'm so excited, I'm practically bouncing in my seat.[1]
But for now, it's the 70cm drive we've got to worry about. Surprisingly, nobody's named the flat white rocks we're driving to, so I suggest "Normandy," and the name sticks. I even attach a picture of the American cemetery at Normandy to the RP uplink report, and for good measure I include the poem "In Flanders Fields" and a picture of the American cemetery at Flanders.
This makes me curious about the target names they chose, so I start looking them up. That's when I realize I've been a total dumbass. The names are those of some French explorers and their ships, not of French places. And "Flinders" really is "Flinders," not "Flanders." The French explorers happened to meet up with Flinders -- a British explorer -- as they were mapping the coast of Australia.
This means "Normandy" doesn't fit into the namespace at all. If I'd known, I'd have suggested "Australia" instead. I quietly edit the uplink report ....
But that's not the only stupid thing I do today. Sean O'Keefe flew out for a picture with the MER team, and Jeff and I get so wrapped up in our work that we miss it. This means I've missed two out of three of the big team pictures (I also missed a recent one with the science team). If I didn't have my own picture with O'Keefe -- and if I hadn't been sitting right in front of him for the third picture, which I did manage to show up for -- I'd be seriously bummed out about this.
If anybody ever finds out how dumb I am, they'll take the rover away from me. And my car keys, and probably my shoelaces.
[Next post: sol 412 (Opportunity sol 392), March 1.]
Footnotes:
[1] These orbital meshes have become a standard part of our toolkit -- and they're even better now. The ones Justin was making came from MGS images; the new ones from from the even higher-resolution HiRISE camera aboard MRO. We can't rely on these meshes for all purposes: good as they are, they can't show you sufficiently detailed topography or all hazard-sized rocks, so we must always be able to prove a drive is safe in terms of images taken from Opportunity herself. Still, they're damned useful for context, and for showing that you're on the right general path, among other things.
2010-02-26
2010-02-25
Opportunity Sol 388 (Spirit Sol 408)
It's a restricted sol -- no downlink until 15:00 or so -- so no rover driving today. But we're going to have a meeting at 16:00 to discuss the results, and get a sense of what we're going to do tomorrow in our weekend planning. (They decide to start at 07:30 tomorrow. Ugh.)
Before the meeting, I check out the images. We reached the craters! And we have a fantastic view; we look as if we're perched on the lip of one, with the other just beyond it. I don't see the third, but I'm not sure where to look. The rover's wheels are cocked hard to the side, which means we had a motion error somewhere; it should have straightened them. So something's wrong, but it went wrong in a pretty good place.
Mark Maimone sees me as I'm heading up to the meeting. "Jeff says the scientists are happy," he says. Well, that's the point of this little enterprise, so I'm quite happy to hear it.
Upstairs, while Matt Golombek effusively praises the results, I'm getting a different picture. They wanted to end up between the two southern craters, but that's clearly not where we are: we're looking to the west and seeing two craters, which can happen in this triplet only if we're to the east of the southeastern crater, not between the southeastern and southwestern craters. I try several times to point this out to Matt, but he's not listening, and eventually I give up. If they're happy, what does it matter?
Our original plan had been to head southeast for the weekend, so that we'd arrive at Vostok Crater on Monday. But the scientists like the view from here, so we're going to delay that a week or so. In the interim, we'll hang out here, imaging the craters and maybe doing a little IDD work.
And, since flash is filling, we'll downlink as much as possible. As one of the scientists points out, there's not much point in getting to Vostok early if we don't have flash space to take any pictures or to do any other work once we get there.
As the meeting is wrapping up, Matt figures out what I've been trying to tell him, that we're not where we thought we were. "Oh, well," he shrugs, "it's still one hell of a spectacular spot."
Courtesy NASA/JPL-Caltech. Matt was right: although this wasn't quite where we wanted to end up, it's a spectacular spot.
Before the meeting, I check out the images. We reached the craters! And we have a fantastic view; we look as if we're perched on the lip of one, with the other just beyond it. I don't see the third, but I'm not sure where to look. The rover's wheels are cocked hard to the side, which means we had a motion error somewhere; it should have straightened them. So something's wrong, but it went wrong in a pretty good place.
Mark Maimone sees me as I'm heading up to the meeting. "Jeff says the scientists are happy," he says. Well, that's the point of this little enterprise, so I'm quite happy to hear it.
Upstairs, while Matt Golombek effusively praises the results, I'm getting a different picture. They wanted to end up between the two southern craters, but that's clearly not where we are: we're looking to the west and seeing two craters, which can happen in this triplet only if we're to the east of the southeastern crater, not between the southeastern and southwestern craters. I try several times to point this out to Matt, but he's not listening, and eventually I give up. If they're happy, what does it matter?
Our original plan had been to head southeast for the weekend, so that we'd arrive at Vostok Crater on Monday. But the scientists like the view from here, so we're going to delay that a week or so. In the interim, we'll hang out here, imaging the craters and maybe doing a little IDD work.
And, since flash is filling, we'll downlink as much as possible. As one of the scientists points out, there's not much point in getting to Vostok early if we don't have flash space to take any pictures or to do any other work once we get there.
As the meeting is wrapping up, Matt figures out what I've been trying to tell him, that we're not where we thought we were. "Oh, well," he shrugs, "it's still one hell of a spectacular spot."
Courtesy NASA/JPL-Caltech. Matt was right: although this wasn't quite where we wanted to end up, it's a spectacular spot.
2010-02-24
Opportunity Sol 387 (Spirit Sol 407)
Alicia Fallacaro's the KOP -- the Keeper of the Plan -- and since the KOP runs the software that acts as our planning whiteboard, we can't get started without her. When she comes in, Matt Golombek scowls at her. "You're three minutes late!" "That's OK," I tell her sotto voce, "you saved the rest of us from being late -- we all just got here." This sparks an idea in Brian: on early mornings like this, we should pick some crucial team member to be "the late one," so everyone else can straggle in a little late without being so noticeable.
But it doesn't take long for Matt's mood to improve. "The rover planners should be severely applauded for their great work this weekend," he says. (Well, "severely applauded?" Maybe his mood's not so good, at that.) We did about 389m total for the three-day weekend, shattering records. The first slide the Long-Term Planning lead puts up is a diagram showing how this insane megadrive has affected us. There's a line on the diagram showing how much cumulative progress we'd have to have made each sol in order to get to Vostok on schedule, a straight line running diagonally up the slide. The other line shows our actual progress. It lags well below the target line, and then, this weekend, suddenly shoots up vertically, putting us well ahead of schedule.
"Holy cow!" says one of the remote scientists, voicing my thinking exactly. "I haven't seen a diagram like that since back in the Bonneville days!"
Yeah, I remember those days. The days when we thought a 70m drive was really impressive. Thisol we're going for about 90m, and it doesn't feel like much. However, we're not heading south, to Vostok. Instead, we're cutting west, to a crater triplet dubbed "Trieste." Our imaging is lousy, and even if it were better, we wouldn't have very reliable range data at that distance. But the drive azimuth is a doddle to determine, and Tim Parker has done a localization in the orbital data, which should tell us the desired drive distance.
Note that I say "should." As in, should, but doesn't. This is because Tim's in San Diego, and Matt forgot to write down what Tim told him.
Fortunately, Tim has a cell phone, and Matt's able to find him. We work out the azimuth and direction of the actual desired destination, and that's it. Except that Mark Maimone stops by immediately before the walkthrough, and we end up changing half of the sequence.
Oy.
But it doesn't take long for Matt's mood to improve. "The rover planners should be severely applauded for their great work this weekend," he says. (Well, "severely applauded?" Maybe his mood's not so good, at that.) We did about 389m total for the three-day weekend, shattering records. The first slide the Long-Term Planning lead puts up is a diagram showing how this insane megadrive has affected us. There's a line on the diagram showing how much cumulative progress we'd have to have made each sol in order to get to Vostok on schedule, a straight line running diagonally up the slide. The other line shows our actual progress. It lags well below the target line, and then, this weekend, suddenly shoots up vertically, putting us well ahead of schedule.
"Holy cow!" says one of the remote scientists, voicing my thinking exactly. "I haven't seen a diagram like that since back in the Bonneville days!"
Yeah, I remember those days. The days when we thought a 70m drive was really impressive. Thisol we're going for about 90m, and it doesn't feel like much. However, we're not heading south, to Vostok. Instead, we're cutting west, to a crater triplet dubbed "Trieste." Our imaging is lousy, and even if it were better, we wouldn't have very reliable range data at that distance. But the drive azimuth is a doddle to determine, and Tim Parker has done a localization in the orbital data, which should tell us the desired drive distance.
Note that I say "should." As in, should, but doesn't. This is because Tim's in San Diego, and Matt forgot to write down what Tim told him.
Fortunately, Tim has a cell phone, and Matt's able to find him. We work out the azimuth and direction of the actual desired destination, and that's it. Except that Mark Maimone stops by immediately before the walkthrough, and we end up changing half of the sequence.
Oy.
2010-02-20
Opportunity Sol 384 (Spirit Sol 404)
Once again, I'm in on the weekend -- rather, on a holiday, this time -- to check Opportunity's progress and ensure she's safe to continue. The images show up a few minutes after I do, and again they show a clear road ahead. She put about 104m on the wheels thisol, all of it autonav. I don't know whether we set an autonav record yestersol, but if we did, we beat it thisol. In any case, this is definitely a record; whatever the previous autonav max was, I know it was under 100m.
Once again, we're ready to let the rover proceed on her own for an entire sol. Mark's happy, Art's gleeful. And I'm euphoric.
[Next post: sol 407 (Opportunity sol 387), February 24.]
Once again, we're ready to let the rover proceed on her own for an entire sol. Mark's happy, Art's gleeful. And I'm euphoric.
[Next post: sol 407 (Opportunity sol 387), February 24.]
2010-02-19
Opportunity Sol 383 (Spirit Sol 403)
We got the downlink from the first of our weekend drives. This is the combined blind + autonav drive. Mark Maimone and I sit in the SMSA, looking at the downlink. The images show that the way ahead is totally clear, all the way to the horizon. So whatever else we see in the downlink, this is pretty much enough to tell us we should proceed on the next sol.
But how far did we get?
"177.5m total," Mark reports. "About 105m blind, 72m more autonav."
Oh, well, I say to myself philosophically. It would have been nice to set the record, but at least -- "Hey, wait a minute!" I exclaim. "That is a record!"
And it is. Indeed, it's at least two records. The previous single-sol total was 156.55m, so we beat the heck out of that. And the previous single-sol blind-drive record was about 92m; we beat that too. I don't know what the single-sol autonav record was, but I wouldn't be surprised if that's a third record broken. They won't last long, but it's nice to hold the records once again.
We actually got some bonus blind driving. In order to help the rover keep itself safe, we increasingly tightened its suspension limits the farther out it got: if it tried to drive over something too tall, or into something too deep, the suspension would articulate beyond the limit and the blind drive would stop. Then the sequence would automatically clear the error, back up into presumably safe territory (it had just driven through that area successfully), and continue on autonav. That way, even if the blind drive faulted out, we'd be able to use autonav to salvage part of it.
As it happened, the suspension limit triggered at the very end of the blind drive, as the rover was turning around to switch from blind driving to autonav. So it had already completed the entire planned blind drive, and then we got a few bonus meters on the wheels as it backed up.
We simply couldn't have planned this. Art agrees, when I call him to tell him the great news: "This is just too good!"
But how far did we get?
"177.5m total," Mark reports. "About 105m blind, 72m more autonav."
Oh, well, I say to myself philosophically. It would have been nice to set the record, but at least -- "Hey, wait a minute!" I exclaim. "That is a record!"
And it is. Indeed, it's at least two records. The previous single-sol total was 156.55m, so we beat the heck out of that. And the previous single-sol blind-drive record was about 92m; we beat that too. I don't know what the single-sol autonav record was, but I wouldn't be surprised if that's a third record broken. They won't last long, but it's nice to hold the records once again.
We actually got some bonus blind driving. In order to help the rover keep itself safe, we increasingly tightened its suspension limits the farther out it got: if it tried to drive over something too tall, or into something too deep, the suspension would articulate beyond the limit and the blind drive would stop. Then the sequence would automatically clear the error, back up into presumably safe territory (it had just driven through that area successfully), and continue on autonav. That way, even if the blind drive faulted out, we'd be able to use autonav to salvage part of it.
As it happened, the suspension limit triggered at the very end of the blind drive, as the rover was turning around to switch from blind driving to autonav. So it had already completed the entire planned blind drive, and then we got a few bonus meters on the wheels as it backed up.
We simply couldn't have planned this. Art agrees, when I call him to tell him the great news: "This is just too good!"
2010-02-18
Opportunity Sol 382 (Spirit Sol 402)
We planned two sols yesterday, and we're planning three today -- for President's Day Weekend. Saturday, Sunday, and Monday are all going to be drive days.
And what drive days! Friday, we do one hour of blind driving followed by 2.5 hours of autonav. Saturday and Sunday are each four hours of autonav -- we'll just let the rover pick up where it left off the sol before, and continue to find its own way south. The combined total distance for the three sols might be 350m, possibly even more! As Justin Maki points out, we'll basically do two-thirds of our mission success driving in one weekend.
Fitting all this driving in is going to require some work. They'd originally planned to spend the rest of each sol doing some remote science, but our power situation is such that we can't. So the science team ruthlessly cuts science until the drive fits. We have to cut some of the post-drive drive-support imaging, but it's not a big deal. As long as we get the drive-direction FHAZ images, we'll be fine. And we'll get NCAMs on top of those, so we're gold.
The rover's continued (Saturday and Sunday) driving will be autonomous, but depending on what we see in the downlink, we could want to pull the plug. So we'll have to come in over the weekend, just long enough to evaluate the downlink and say whether we think it's safe for Opportunity to go on. Theoretically, we might decide on Monday that we need to re-plan the drive, but that doesn't look likely. Nobody wants to call the team in on a holiday anyway.
We plan the drive. We cross our fingers. We go home.
But not before saying goodbye to Julie Townsend, who's moving on to other work. She hugs Art and tells him she's had the time of her life. "I know what you mean," he says. "You work on something like Pathfinder, and you think nothing will ever be like that again. And then something like this comes along."
And what drive days! Friday, we do one hour of blind driving followed by 2.5 hours of autonav. Saturday and Sunday are each four hours of autonav -- we'll just let the rover pick up where it left off the sol before, and continue to find its own way south. The combined total distance for the three sols might be 350m, possibly even more! As Justin Maki points out, we'll basically do two-thirds of our mission success driving in one weekend.
Fitting all this driving in is going to require some work. They'd originally planned to spend the rest of each sol doing some remote science, but our power situation is such that we can't. So the science team ruthlessly cuts science until the drive fits. We have to cut some of the post-drive drive-support imaging, but it's not a big deal. As long as we get the drive-direction FHAZ images, we'll be fine. And we'll get NCAMs on top of those, so we're gold.
The rover's continued (Saturday and Sunday) driving will be autonomous, but depending on what we see in the downlink, we could want to pull the plug. So we'll have to come in over the weekend, just long enough to evaluate the downlink and say whether we think it's safe for Opportunity to go on. Theoretically, we might decide on Monday that we need to re-plan the drive, but that doesn't look likely. Nobody wants to call the team in on a holiday anyway.
We plan the drive. We cross our fingers. We go home.
But not before saying goodbye to Julie Townsend, who's moving on to other work. She hugs Art and tells him she's had the time of her life. "I know what you mean," he says. "You work on something like Pathfinder, and you think nothing will ever be like that again. And then something like this comes along."
2010-02-17
Opportunity Sol 381 (Spirit Sol 401)
Thisol we're completing our IDD work on Russet, after which we drive to the Alvin and Jason craters.
The drive to Alvin and Jason is my first time planning a drive using orbital imagery. We don't have good enough NCAM or PCAM imagery to reliably drive as close to the craters as we want, so at Jeff's suggestion, Brian and I go downstairs to work with Tim Parker to plan the drive. He's basically got an imaging program with the rover localized to a point in an orbital picture, and he can draw lines of various lengths and at different angles. He's clearly been getting a lot of practice: with his help, it takes just a few minutes to work out the drive.[1]
Sadly, the science team has decided they want to drive between the craters after all (not skirting them by driving south of Jason, as I'd suggested a few sols ago). On closer inspection of the imagery we do have, the crater my plan would have avoided turns out to be the more interesting one, as it appears to contain outcrop material. But that's OK, this isn't our big drive sol.
Our big drive sol comes next. Or, more accurately, our series of big drive sols. We're going to head south in a big way, continuing to Vostok by way of a cluster of three craters more than 300m south of us. Though I doubt this is possible, I'm hoping to make it there in two sols, which would almost certainly mean breaking the distance record once more (however briefly, before it's broken again). For the record -- no pun intended -- the current single-sol drive-distance record is 156.55m. I'll have a few chances to break it. Even if I don't succeed, it'll be fun to try.
[1] A much-refined version of this approach has become the norm for Opportunity's long drives across Meridiani Planum -- as we're doing now to make our way to Endeavour, for instance. Tim Parker and Matt Golombek lay out a large-scale traverse path, and the RPs make tactical decisions about how closely to follow it, based on what we actually see from the surface each sol.
The drive to Alvin and Jason is my first time planning a drive using orbital imagery. We don't have good enough NCAM or PCAM imagery to reliably drive as close to the craters as we want, so at Jeff's suggestion, Brian and I go downstairs to work with Tim Parker to plan the drive. He's basically got an imaging program with the rover localized to a point in an orbital picture, and he can draw lines of various lengths and at different angles. He's clearly been getting a lot of practice: with his help, it takes just a few minutes to work out the drive.[1]
Sadly, the science team has decided they want to drive between the craters after all (not skirting them by driving south of Jason, as I'd suggested a few sols ago). On closer inspection of the imagery we do have, the crater my plan would have avoided turns out to be the more interesting one, as it appears to contain outcrop material. But that's OK, this isn't our big drive sol.
Our big drive sol comes next. Or, more accurately, our series of big drive sols. We're going to head south in a big way, continuing to Vostok by way of a cluster of three craters more than 300m south of us. Though I doubt this is possible, I'm hoping to make it there in two sols, which would almost certainly mean breaking the distance record once more (however briefly, before it's broken again). For the record -- no pun intended -- the current single-sol drive-distance record is 156.55m. I'll have a few chances to break it. Even if I don't succeed, it'll be fun to try.
[1] A much-refined version of this approach has become the norm for Opportunity's long drives across Meridiani Planum -- as we're doing now to make our way to Endeavour, for instance. Tim Parker and Matt Golombek lay out a large-scale traverse path, and the RPs make tactical decisions about how closely to follow it, based on what we actually see from the surface each sol.
2010-02-16
Opportunity Sol 380 (Spirit Sol 400)
The good news is, we're in that phase where our start time is slipping later and later. The bad news is, I have to come in early today anyway, for a meeting. At least it's something MER-related: it's Jeff and Mark bringing us RPs up to speed on the new mobility flight software. (Just to twist the knife, Frank suggests a way to surreptitiously use one of the new features to ensure I don't get a chance to drive very far. "The way things have been going," I reply wryly, "it's not like you have to work hard to ensure that.")
After that, it's a relatively slow day in RP-land. Russet ended up dead ahead of us, just where we wanted it, in a perfectly cromulent spot for IDDing. We're just going to MB and APXS it thisol. It takes me maybe half an hour to crank out the sequences.
At least I got to name something again. In keeping with the potato theme, Albert Yen named one of the targets "Eye." Then, working down the side, he named two more targets "Nose" and "Mouth." We ended up choosing a location between Eye and Nose, which I named BridgeOfNose.
Well, as I said, it was a relatively slow day.
After that, it's a relatively slow day in RP-land. Russet ended up dead ahead of us, just where we wanted it, in a perfectly cromulent spot for IDDing. We're just going to MB and APXS it thisol. It takes me maybe half an hour to crank out the sequences.
At least I got to name something again. In keeping with the potato theme, Albert Yen named one of the targets "Eye." Then, working down the side, he named two more targets "Nose" and "Mouth." We ended up choosing a location between Eye and Nose, which I named BridgeOfNose.
Well, as I said, it was a relatively slow day.
2010-02-15
Opportunity Sol 379 (Spirit Sol 399)
Charles has a beautiful shiner. I can't resist asking him about it.
"Friday was not a good day for me," he says. "I was driving through Old Town Pasadena, turning down Fair Oaks, and I hit a pedestrian. I got out of my car to check on her, and this guy yelled, 'You hit her!' and sucker-punched me." He mimes throwing his head back as a result of the punch. "That was his contribution to the situation. I've got problems, but he has a felony assault charge."
Yee-ouch.
Yesterday they ran a checkout of the new mobility flight software. It looks like it generally went well. At least the vehicle didn't die. And it ended up near where it was supposed to. But not quite where it was supposed to -- it's about 1.8m away from its intended destination, a ten percent error or so, and Jeff and Mark aren't sure why. It might be something as benign as simple error in the previous sols' images -- that is, the things in the world might not have been exactly where we thought they were, which would explain why they're still not, if you see what I mean. But until we're sure, we don't want to go much of anywhere.
Which is fine by the scientists. The intended target of our drive, a possible meteorite dubbed "Russet" (as in the potato), is directly in front of our right front wheel. So thisol's drive is just a turn in place, to put Russet in our work volume. It takes me barely five minutes to write it.
That gives me some time to participate in the planning for the upcoming drives. If I'm lucky, by the end of the week we'll be back to the routine of long driving I missed the last round of. I might yet get my shot at another record! (Probably not -- we likely can't outdo what's been done -- but at least for now I can hope.) Our next near-term goal will be to skate between a couple of craters currently about 40m southwest of us, stopping on the way by to image them. Then we'll turn more to the south and floor it.
As usual, there's a problem. The craters are far enough apart that we won't be able to image both of them well from a single spot. Ray and the other scientists say they're more interested in the southern crater, so I suggest a different plan. My idea is, don't bother going between the two craters and then turning south. Just go to the south of the southern crater, image it from relatively close (and image the other one as well as we can), and move on. This takes us less far out of our way and gets them equivalent results.
"Scott's pretty smart!" Ray exclaims. "I'm glad you're here, buddy!"
No doubt about it: I'm definitely having a better day than Charles.
Courtesy NASA/JPL-Caltech. Russet is just in front of Opportunity's RF wheel. You want me to drive all the way to Russet? In just one sol? Well, I do like a challenge ....
"Friday was not a good day for me," he says. "I was driving through Old Town Pasadena, turning down Fair Oaks, and I hit a pedestrian. I got out of my car to check on her, and this guy yelled, 'You hit her!' and sucker-punched me." He mimes throwing his head back as a result of the punch. "That was his contribution to the situation. I've got problems, but he has a felony assault charge."
Yee-ouch.
Yesterday they ran a checkout of the new mobility flight software. It looks like it generally went well. At least the vehicle didn't die. And it ended up near where it was supposed to. But not quite where it was supposed to -- it's about 1.8m away from its intended destination, a ten percent error or so, and Jeff and Mark aren't sure why. It might be something as benign as simple error in the previous sols' images -- that is, the things in the world might not have been exactly where we thought they were, which would explain why they're still not, if you see what I mean. But until we're sure, we don't want to go much of anywhere.
Which is fine by the scientists. The intended target of our drive, a possible meteorite dubbed "Russet" (as in the potato), is directly in front of our right front wheel. So thisol's drive is just a turn in place, to put Russet in our work volume. It takes me barely five minutes to write it.
That gives me some time to participate in the planning for the upcoming drives. If I'm lucky, by the end of the week we'll be back to the routine of long driving I missed the last round of. I might yet get my shot at another record! (Probably not -- we likely can't outdo what's been done -- but at least for now I can hope.) Our next near-term goal will be to skate between a couple of craters currently about 40m southwest of us, stopping on the way by to image them. Then we'll turn more to the south and floor it.
As usual, there's a problem. The craters are far enough apart that we won't be able to image both of them well from a single spot. Ray and the other scientists say they're more interested in the southern crater, so I suggest a different plan. My idea is, don't bother going between the two craters and then turning south. Just go to the south of the southern crater, image it from relatively close (and image the other one as well as we can), and move on. This takes us less far out of our way and gets them equivalent results.
"Scott's pretty smart!" Ray exclaims. "I'm glad you're here, buddy!"
No doubt about it: I'm definitely having a better day than Charles.
Courtesy NASA/JPL-Caltech. Russet is just in front of Opportunity's RF wheel. You want me to drive all the way to Russet? In just one sol? Well, I do like a challenge ....
2010-02-09
Opportunity Sol 372 (Spirit Sol 393)
The scuff worked out just as intended and is now in front of us, perfectly positioned for us to IDD it. But Rick Welch suggests abandoning this opportunity. We have a new FSW load coming up, and he thinks it might be a good idea to get the rover into a good attitude for that. We wouldn't leave the scuff altogether, but we'd try to drive to a different location, one from which we could still reach the scuff while being better positioned for the FSW load.
But the science team nixes the idea. "We've got this," one of them says, "let's use it."
Well, they won't have Rick to kick around any more. Not for long, anyhow. He's moving on to MSL after this week, and Julie Townsend is doing the same. "The last remnants of the original team are floating away," she muses.
Speaking of MSL, Jeff heard a disturbing rumor. The flight software architecture for MSL, he heard, is going to be based on a system called VML. Nothing wrong with that -- if you have an orbiter, or even a lander. But for a rover, VML doesn't make sense. This is because VML requires every command to be time-tagged; it doesn't seem (says Jeff) to have an event-driven mode. (That's what we call a mode that says, "do each command as soon as the previous command finishes.") That's the mode in which we always command the rovers. Time-tagging all commands makes sense when you have an orbiter, whose environment can be perfectly predicted months in advance, or even a lander, whose environment is more or less fixed. But for a vehicle that has to dynamically respond to an unpredictable environment, this would be absurd.[1]
And maybe it's not true -- we don't know enough about VML to know. "One good thing if it is true," I point out. "It'll sure help me decide if I want to work on that project."
[Next post: sol 399 (Opportunity sol 379), February 15.]
[1] I don't know whether VML was ever seriously in contention as the basis for MSL's flight software or if this was simply a baseless rumor, but in any case VML is not being used on MSL.
But the science team nixes the idea. "We've got this," one of them says, "let's use it."
Well, they won't have Rick to kick around any more. Not for long, anyhow. He's moving on to MSL after this week, and Julie Townsend is doing the same. "The last remnants of the original team are floating away," she muses.
Speaking of MSL, Jeff heard a disturbing rumor. The flight software architecture for MSL, he heard, is going to be based on a system called VML. Nothing wrong with that -- if you have an orbiter, or even a lander. But for a rover, VML doesn't make sense. This is because VML requires every command to be time-tagged; it doesn't seem (says Jeff) to have an event-driven mode. (That's what we call a mode that says, "do each command as soon as the previous command finishes.") That's the mode in which we always command the rovers. Time-tagging all commands makes sense when you have an orbiter, whose environment can be perfectly predicted months in advance, or even a lander, whose environment is more or less fixed. But for a vehicle that has to dynamically respond to an unpredictable environment, this would be absurd.[1]
And maybe it's not true -- we don't know enough about VML to know. "One good thing if it is true," I point out. "It'll sure help me decide if I want to work on that project."
[Next post: sol 399 (Opportunity sol 379), February 15.]
[1] I don't know whether VML was ever seriously in contention as the basis for MSL's flight software or if this was simply a baseless rumor, but in any case VML is not being used on MSL.
2010-02-08
Opportunity Sol 371 (Spirit Sol 392)
Oddly, we have no images from sol 369. We know the rover's not dead; we have images from sol 370. But for 369, nothing but thumbnails. It makes an odd gap in the data -- I don't remember ever seeing that happen before. They'll come down eventually, but not until our downlink improves.
Thisol we're going to finish up with the damn trench already. Still, we're not ready to leave. (Hell, we wouldn't want me to drive somewhere -- I might get a chance to break a record. Grumble, grumble.) Since we couldn't IDD the scuff we made earlier, we're going to make another one and IDD that. The last one appeared to dig farther into the soil than they'd wanted, so this one's going to be simpler and shorter: we'll just run the left front wheel back and forth a bit, then back off and turn.
Or that's Rob Sullivan's plan. But Julie points out that that will leave the rover at an azimuth of 210 degrees -- not bad for comm, but we could do better. "Better" would be a radically different heading, 80 or 90 degrees -- split the difference and say 85 -- where we'd get 100 Mbits more downlink each sol. 100 Mbits is a lot of saved-up images, so I start thinking about how to accomplish this.
We can't scuff just anywhere, we need to ensure that the wheel's not on a ripple. Our view of the immediate area isn't that great, so to ensure success, we really want to scuff the spot where the left front wheel is now. In order to be at 85 and IDDing the scuff, the spot we need the rover to be in is in front of us and to the right of where we are now. If we scuff and then drive to that spot, we'll either drive through the scuff, contaminating it, or through the trench, which they haven't finished imaging yet.
It's time for a creative solution, and I think of one: don't scuff with the left front wheel, scuff with the left rear wheel, after putting it where the left front wheel is now. That is, instead of scuff/drive forward/turn/back off, we could drive forward/scuff (with rear wheel)/turn/back off. By design, the trench is just a bit narrower than the wheel base, so we can even do this without disturbing the trench -- we'll just straddle it.
While Jeff writes the IDD sequences, Jeng and I develop the drive, but in the end it simply proves too complex. This is already our second try at the scuff, and nobody wants to have to make a third -- even the scientists are ready to drive on. As much as I love my idea (and I'm not the only one), it's not The Simplest Thing That Could Possibly Work. So we revert to Rob's original plan: scuff, back off a bit, and turn. Simple, effective -- and, unfortunately, 100 Mbits/sol less downlink.
In refining the scuff part of the drive, we introduce an unusual move. The original idea was to run the left front wheel backward, to kick away any material it might have tracked in underneath it, then run it forward to create the scuff, and then back up. But in order to help create a clean scuff, we need to drive the rover back very slightly, just a centimeter or so.
At first, Jeff's not even sure such a short drive will work. But it works fine when we run it through the simulation, so he shrugs and blesses it. He turns to me and says, "I don't think we've ever done a drive that short on Mars. Hey, I guess you got to set a record after all!"
Gee, I'm so proud.
Thisol we're going to finish up with the damn trench already. Still, we're not ready to leave. (Hell, we wouldn't want me to drive somewhere -- I might get a chance to break a record. Grumble, grumble.) Since we couldn't IDD the scuff we made earlier, we're going to make another one and IDD that. The last one appeared to dig farther into the soil than they'd wanted, so this one's going to be simpler and shorter: we'll just run the left front wheel back and forth a bit, then back off and turn.
Or that's Rob Sullivan's plan. But Julie points out that that will leave the rover at an azimuth of 210 degrees -- not bad for comm, but we could do better. "Better" would be a radically different heading, 80 or 90 degrees -- split the difference and say 85 -- where we'd get 100 Mbits more downlink each sol. 100 Mbits is a lot of saved-up images, so I start thinking about how to accomplish this.
We can't scuff just anywhere, we need to ensure that the wheel's not on a ripple. Our view of the immediate area isn't that great, so to ensure success, we really want to scuff the spot where the left front wheel is now. In order to be at 85 and IDDing the scuff, the spot we need the rover to be in is in front of us and to the right of where we are now. If we scuff and then drive to that spot, we'll either drive through the scuff, contaminating it, or through the trench, which they haven't finished imaging yet.
It's time for a creative solution, and I think of one: don't scuff with the left front wheel, scuff with the left rear wheel, after putting it where the left front wheel is now. That is, instead of scuff/drive forward/turn/back off, we could drive forward/scuff (with rear wheel)/turn/back off. By design, the trench is just a bit narrower than the wheel base, so we can even do this without disturbing the trench -- we'll just straddle it.
While Jeff writes the IDD sequences, Jeng and I develop the drive, but in the end it simply proves too complex. This is already our second try at the scuff, and nobody wants to have to make a third -- even the scientists are ready to drive on. As much as I love my idea (and I'm not the only one), it's not The Simplest Thing That Could Possibly Work. So we revert to Rob's original plan: scuff, back off a bit, and turn. Simple, effective -- and, unfortunately, 100 Mbits/sol less downlink.
In refining the scuff part of the drive, we introduce an unusual move. The original idea was to run the left front wheel backward, to kick away any material it might have tracked in underneath it, then run it forward to create the scuff, and then back up. But in order to help create a clean scuff, we need to drive the rover back very slightly, just a centimeter or so.
At first, Jeff's not even sure such a short drive will work. But it works fine when we run it through the simulation, so he shrugs and blesses it. He turns to me and says, "I don't think we've ever done a drive that short on Mars. Hey, I guess you got to set a record after all!"
Gee, I'm so proud.
2010-02-05
Opportunity Sol 368 (Spirit Sol 389)
Thanks to the frenzy of yesterday, the pressure is somewhat reduced today. Today's uplink was done yesterday, so today (Friday) we just have to do Saturday's and Sunday's uplinks. It's just as much work, but we can run late if we have to.
Our downlink must be poor. We've only gotten one MI so far, but it looks spectacular. Unfortunately, it doesn't quite cover the area the scientists wanted. RSVP showed we should expect to just see over the top of the trench, which is exactly what they asked for, but it seems the image we got is somewhat farther down the trench wall than that. It's not clear we've got enough room in the plan to reshoot them today, but we'll have to reshoot them before leaving because they're probably the highest-priority scientific target in the trench. Between that, and the MB team's deciding that they want additional integration time in the trench for better statistics, they decide to change the plan. We won't bump to the scuff on Monday, we'll continue our trench work.
This sucks for two reasons. First, it means we need to redo a large chunk of the plan, which in turn means not only that we wasted a whole bunch of time yesterday but also that we're going to have that much less time for sequencing today. Far more important to me, though, is that this means I won't get a chance for a long drive in this cycle of shifts. I'm on only until Tuesday, and then I'm off shift again for about a week. I was really pushing to get all of the trench work finished by Monday, but with the decision to spend an extra day at the trench, we'll finish Tuesday instead. So I'll have spent this entire shift cycle screwing around with the trench, and the RPs who come in after me will be doing the fun record-setting drives, while I spend that time slogging through some decidedly dull MSL-related work.
Worst of all, I have nobody to blame for it but myself. MB notwithstanding, I doubt we'd spend the extra time here if the MIs had covered the desired area. And guess who took the MIs.
Intellectually, I can see that I'm being churlish about this. (Oh, woe is me. I get paid to play with a Mars rover, but I'm not driving it very long distances right at the moment. My life is such a misery.) But knowing that doesn't seem to improve my attitude -- to the contrary, it's making it worse. I might need to take a couple of days off.
So might Matt Golombek. He's having a hard time wrangling the scientists, so the SOWG meeting is going slowly. He turns around to face the engineering team (us), which sits along the row behind him. "Damn scientists!" he blurts out -- only half-kidding, if I'm reading him right. "Welcome to the back row," replies fellow engineer Geoff Lake.
As expected, today's another long day. Jeff and I improve our process -- we develop the two sols in parallel, as we did yesterday, but we exchange sequences earlier in the day, which I think makes a lot of difference. Once again, the TULs and TAP/SIEs have to work through a variety of software problems, but at least we've figured out why this keeps happening.
It's happening because we're improving things. Sharon Laubach has been developing a bunch of scripts for automating the ground system. Mostly, she develops these in her home directory, and then at some point she informally delivers them to the team by putting them in a semipublic location. At the same time, she starts the process of delivering them to Configuration Management, who's responsible for installing them officially on all the systems. CM just officially installed her new stuff, so Sharon duly removed her semipublic copies.
The only problem is, CM installed her new stuff on the Suns only, not on the Linux systems. Most of our work gets done on the Linux systems. So a lot of stuff broke.
The team's collective opinion is that CM needs to take a few days off, too. And not come back.
[Next post: sol 392 (Opportunity sol 371), February 8.]
Our downlink must be poor. We've only gotten one MI so far, but it looks spectacular. Unfortunately, it doesn't quite cover the area the scientists wanted. RSVP showed we should expect to just see over the top of the trench, which is exactly what they asked for, but it seems the image we got is somewhat farther down the trench wall than that. It's not clear we've got enough room in the plan to reshoot them today, but we'll have to reshoot them before leaving because they're probably the highest-priority scientific target in the trench. Between that, and the MB team's deciding that they want additional integration time in the trench for better statistics, they decide to change the plan. We won't bump to the scuff on Monday, we'll continue our trench work.
This sucks for two reasons. First, it means we need to redo a large chunk of the plan, which in turn means not only that we wasted a whole bunch of time yesterday but also that we're going to have that much less time for sequencing today. Far more important to me, though, is that this means I won't get a chance for a long drive in this cycle of shifts. I'm on only until Tuesday, and then I'm off shift again for about a week. I was really pushing to get all of the trench work finished by Monday, but with the decision to spend an extra day at the trench, we'll finish Tuesday instead. So I'll have spent this entire shift cycle screwing around with the trench, and the RPs who come in after me will be doing the fun record-setting drives, while I spend that time slogging through some decidedly dull MSL-related work.
Worst of all, I have nobody to blame for it but myself. MB notwithstanding, I doubt we'd spend the extra time here if the MIs had covered the desired area. And guess who took the MIs.
Intellectually, I can see that I'm being churlish about this. (Oh, woe is me. I get paid to play with a Mars rover, but I'm not driving it very long distances right at the moment. My life is such a misery.) But knowing that doesn't seem to improve my attitude -- to the contrary, it's making it worse. I might need to take a couple of days off.
So might Matt Golombek. He's having a hard time wrangling the scientists, so the SOWG meeting is going slowly. He turns around to face the engineering team (us), which sits along the row behind him. "Damn scientists!" he blurts out -- only half-kidding, if I'm reading him right. "Welcome to the back row," replies fellow engineer Geoff Lake.
As expected, today's another long day. Jeff and I improve our process -- we develop the two sols in parallel, as we did yesterday, but we exchange sequences earlier in the day, which I think makes a lot of difference. Once again, the TULs and TAP/SIEs have to work through a variety of software problems, but at least we've figured out why this keeps happening.
It's happening because we're improving things. Sharon Laubach has been developing a bunch of scripts for automating the ground system. Mostly, she develops these in her home directory, and then at some point she informally delivers them to the team by putting them in a semipublic location. At the same time, she starts the process of delivering them to Configuration Management, who's responsible for installing them officially on all the systems. CM just officially installed her new stuff, so Sharon duly removed her semipublic copies.
The only problem is, CM installed her new stuff on the Suns only, not on the Linux systems. Most of our work gets done on the Linux systems. So a lot of stuff broke.
The team's collective opinion is that CM needs to take a few days off, too. And not come back.
[Next post: sol 392 (Opportunity sol 371), February 8.]
2010-02-04
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.
Ahem.
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 ....
Footnotes:
[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.
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.
Ahem.
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 ....
Footnotes:
[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.
2010-02-03
Opportunity Sol 366 (Spirit Sol 387)
So the last sol I was on shift, we drove 70m or so away from the heat shield, just to get the rover well clear of it. Since then, every sol's been devoted to charging across the plains as fast as possible, doing drives so long they have to plan them with orbital maps. My single-sol blind-driving record is gone, never to return (the bastards just had to take that away from me, breaking my record by a meter or so), and the single-sol total-distance record is now up to 154m or so. But now it's my turn again, and I'm ready to floor it.
So of course, they picked today to stop and IDD for a while. We're going to dig a trench and poke around in it, right up through my last day in this group of shifts. Then they're going to drive some more.
No, I'm not kidding. I couldn't make this up if I tried.
One of the scientists, Rob Sullivan, already worked out most of what needed to be done. We have a lot of analysis to do, but really, he's done most of the hard work for us.
Not that this stops him from being genuinely appreciative of our work. "You guys are just great," he enthuses over the telecom. "Really, if people knew all the stuff you guys have to do every day ...." He continues in this vein for a full minute, maybe more. It's wonderful -- it almost makes up for not getting to do a long drive. After listening to Rob's effusion of praise, Andy replies, "Remember this at performance evaluation time!"
If Rob is appreciative, Frank is sympathetic. He stops by to see how things are going, and I complain (reasonably good-naturedly) about my getting shut out of the driving. "I feel for you, man," Frank says.
"So you'd be willing to trade some shifts with me?" I tease him.
"I'm not gonna lie to you," he says. "When I saw the upcoming plan, I was like, thank God I'm off for those few days."
At least he's honest about it. "I can't blame you," I shrug. "If the situation were reversed, I have to admit I'd feel the same way."
Well, one of the great aspects of my job is that even on the worst days -- even on the very worst days -- I get to drive a Mars rover. And that's not what I'd call bad.
So of course, they picked today to stop and IDD for a while. We're going to dig a trench and poke around in it, right up through my last day in this group of shifts. Then they're going to drive some more.
No, I'm not kidding. I couldn't make this up if I tried.
One of the scientists, Rob Sullivan, already worked out most of what needed to be done. We have a lot of analysis to do, but really, he's done most of the hard work for us.
Not that this stops him from being genuinely appreciative of our work. "You guys are just great," he enthuses over the telecom. "Really, if people knew all the stuff you guys have to do every day ...." He continues in this vein for a full minute, maybe more. It's wonderful -- it almost makes up for not getting to do a long drive. After listening to Rob's effusion of praise, Andy replies, "Remember this at performance evaluation time!"
If Rob is appreciative, Frank is sympathetic. He stops by to see how things are going, and I complain (reasonably good-naturedly) about my getting shut out of the driving. "I feel for you, man," Frank says.
"So you'd be willing to trade some shifts with me?" I tease him.
"I'm not gonna lie to you," he says. "When I saw the upcoming plan, I was like, thank God I'm off for those few days."
At least he's honest about it. "I can't blame you," I shrug. "If the situation were reversed, I have to admit I'd feel the same way."
Well, one of the great aspects of my job is that even on the worst days -- even on the very worst days -- I get to drive a Mars rover. And that's not what I'd call bad.
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