Help - Search - Members - Calendar
Full Version: Getting Unstuck in West Valley
Unmanned Spaceflight.com > Mars & Missions > Past and Future > MER > Spirit
Pages: 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22
BrianL
Paolo, can you give us any info on the various test results so far? Anything look promising, or "Eww, that just didn't work at all"?
Julius
I see that Spirit has been stuck around this area on Mars for quite some time now..would that explain the Ulysses and Calypso panorama terms being used following the concept of Ulysses being held on the island of OGYGIA(today island of Calypso) in Homer's famous ODyssey??I'm sure that Spirit will free herself just like Ulysses managed to set himself free from the spell of the nymph Calypso and continue on his voyage of discovery just like Homer had described it! smile.gif
RoverDriver
QUOTE (BrianL @ Jul 12 2009, 08:39 AM) *
Paolo, can you give us any info on the various test results so far? Anything look promising, or "Eww, that just didn't work at all"?


I don't thnk it would be appropriate for me to discuss the results even because we are still evaluating the results. I hope you understand.

Paolo
Tesheiner
QUOTE (Julius @ Jul 13 2009, 06:11 AM) *
I see that Spirit has been stuck around this area on Mars for quite some time now..would that explain the Ulysses and Calypso panorama terms being used following the concept of Ulysses being held on the island of OGYGIA(today island of Calypso) in Homer's famous ODyssey??I'm sure that Spirit will free herself just like Ulysses managed to set himself free from the spell of the nymph Calypso and continue on his voyage of discovery just like Homer had described it! smile.gif


Search for "Calypso" in this very same thread and you'll find the answer, whose first letter is "y". wink.gif
Julius
That Mediterranean Island is my island!!Enjoy! rolleyes.gif
Astro0
Meanwhile OnTopic...

OK, so far as we know up until a few days ago the Rover team have tried 4 or 5 of the first 11 driving maneuvers they want to test.
1) Straight forwards;
2) Straight backwards;
3) 'Crabwalk' - driving upslope with the wheels turned at 60 degrees to the right;
4) 'Crabwalk' - driving upslope with the wheels turned 20 degrees to the right;
5) 'Crabwalk' - driving downslope backwards with the wheels turned 60 degrees to the right;

It's a fair bet that 6) will be:
6) 'Crabwalk' - driving downslope backwards with the wheels turned 20 degrees to the right;

I'd guess that 7 thru 10 will be crabwalks with the wheels at 60 and 20 degrees left(?), and then 11(?)

What do people think will be maneuvers 7 to 11?
Then what techniques after that?

Remember to read the Extraction FAQ to see what they have done, might try, can't do, won't do. wink.gif
Julius
Sorry to seem to be sticking to the same topic but forgive my excitement but as I recall the Odyssey story had come up after naming Santorini at Opportunity's track at Meridiani...but I have to say the idea of the Calypso panorama is a brilliant idea...i believe the genius has been Ustrax!??right?
djellison
I wonder if one technique might be tank-tracking for a rotation
nprev
I thought that "tank mode" was already tried--briefly-- as soon as she got stuck. Doesn't mean it won't be tried again, of course.
RoverDriver
QUOTE (nprev @ Jul 13 2009, 05:07 AM) *
I thought that "tank mode" was already tried--briefly-- as soon as she got stuck. Doesn't mean it won't be tried again, of course.


We actually never tried true tank steering, but we tried a turn in place, which failed because it timed out.

Paolo
BrianL
Thanks, Paolo, I understand completely. Pretty much the answer I expected but I figure it never hurts to ask.

Does anyone have a guess as to the extent of this bad patch? We know where it started but how far does it extend forward... make that, VonBraunward, or off to either side?

djellison
QUOTE (BrianL @ Jul 13 2009, 07:15 PM) *
it never hurts to ask.


It can get a bit tedious though.
fredk
QUOTE (Astro0 @ Jul 13 2009, 01:09 PM) *
What do people think will be maneuvers 7 to 11? Then what techniques after that?

Check out this link for planned maneuvers.
nprev
Thanks for the link, Fred.

Hmm. The 'driving while steering' method is interesting, and one I don't think anyone proposed here. Sounds promising, actually; should we christen it 'sidewinder mode'?
CosmicRocker
That sounds like a perfect name for such a maneuver, Nick. Allow me to second that motion. wink.gif
RoverDriver
QUOTE (nprev @ Jul 13 2009, 09:01 PM) *
Thanks for the link, Fred.

Hmm. The 'driving while steering' method is interesting, and one I don't think anyone proposed here. Sounds promising, actually; should we christen it 'sidewinder mode'?


This is one of my crazy ideas. I have found out that steering (= just changing the pointing of the wheels) makes the SSTB sink a lot because soil gets pushed around by the steering action. I want to try and see if by keeping the soil next to the wheel (by driving it) I can keep the wheel from sinking. Drive and steer normally is not done because driving adds stress to the steering actuator, but in this case it might be useful.

Paolo
nprev
You might be on to something here, Paolo. Driving while slewing the wheels back & forth should also distribute the weight of the vehicle over a greater amount of surface area over a given time (if I phrased that correctly)...or, another way of looking at it, reduce the amount of wheel surface area in contact with a given patch of soil over time. Less digging, more overland motion, maybe?

Guess you're limited to 0.5 second motion increments, right? That still might provide enough advantage to give her some impetus.
briv1016
All this talk of maneuvers... wink.gif

Peter (Han Solo): We'll be safe enough once we make the jump to hyperspace. Besides, I know a few maneuvers. We'll lose'em.
[the Falcon starts listing lazily to the left]
Chris (Luke Skywalker): Uh, that was your maneuver? Moving slightly to the left?
Peter (Han Solo): Well, I mean we're not in the same place we were, huh? That ought to confuse'em.
Chris (Luke Skywalker): Yeah, but you hardly did anything. You just started listing lazily to the left. I'm pretty sure they can keep up.
Imperial Officer 1: Where did they go?
Imperial Officer 2: There they are! They're listing lazily to the left. Go left, left!
Imperial Officer 1: Boy, this guy knows some maneuvers.
alan
Calypso panorama so far
Click to view attachment
Shaka
Nice work, Alan!
If we get out of this powdery bog, I would feel safer keeping to the east of the von Braun track.
There are too many ominous smooth 'basins' directly toward it and to the west. The rocks are small but rather continuous closer to the Home Plate slope. I would think the footing there would be more secure, as long as the slope is not too extreme (but we have plenty of insolation power!). I used to worry that the stuck wheel might anchor itself on an embedded rock, but we've traversed a lot of rocks since then without getting caught, so, what the devil! Let's get up closer to the exposed strata of HP, and do some science on the way south to von Braun.
Burmese
Article in The Wall Street Journal:

http://online.wsj.com/article/SB1247779493...=googlenews_wsj

Quote that got my attention:

"Working through their first round of 11 rescue experiments, JPL rover engineers wearing protective masks and white "Free Spirit" lab coats gingerly gunned the test rover's engine, then periodically measured its progress with a yardstick. With each trial maneuver, though, the robot dug itself a little deeper"

My question here is, did someone at JPL tell this reporter that the rover just dug itself deeper each test? At a minimum, I would expect that what happened to the test rover in each test would be characterized in more complex terms, not simply "Dug in" or "Dug out". Or was this reporter (Robert Lee Hotz) on hand to observe some test and simply put down his own observations?
MahFL
"Engine and yardstick", the reporter sounds like a hick from some town with one train per week arriving.....LMAO.

He also refers to Spirit as The Spirit, and that they leave tire tracks.

Dumass.
BrianL
Nitpick all you want about his writing style and terminology, at least he is providing some information about what is happening. In the absence of reports to the contrary, I'm prepared to accept that the maneuvers so far have not yielded positive results. It is interesting he talks about 60 maneuvers to be tried, whereas JPL says they are working through a set of 11. Perhaps the 60 represent variations or combinations of the basic 11. Or he just has his facts wrong.
climber
Looks like you're stucked in Venezia, Brian...
PDP8E
Hi all,

I built up a drive movie (hazcam) of Spirit rounding the northern corner of Home plate and then heading down the West Valley...and then getting stuck. The bottom half of the movie is processed to see in the shadows. At one point you can see the IDD arm with MI moving a rock just under the visible deck.

I had to host it off-site (big)

The movie is from the front right hazcam, Spirit is driving backwards, so its like looking out the rear window.
You can see the rover settle into a 12degree roll as the horizon moves in the opposite direction.

http://farm3.static.flickr.com/2523/373110...ddccca876_o.gif

Cheers
helvick
That's fantastic work.
CosmicRocker
QUOTE (PDP8E @ Jul 17 2009, 08:10 PM) *
... At one point you can see the IDD arm with MI moving a rock just under the visible deck.
Good catch. smile.gif

Also, do we see the LF wheel climbing slightly in its last attempt to drive?
JayB
via twitter @marsRovers

Rescuing a rover: Join us Thurs., 3p ET (22UTC) at http://ustre.am/25IX for a live "Free Spirit" video chat/Q & A. Bring your questions!

(Thurs July 23 according to the link)
djellison
Brilliant - I suggested they do that after the last Ustreamage smile.gif
PDP8E
Hi all,

Here is another hazcam drive movie of Spirit entering West Valley and getting stuck...this time from the front of the (backwards driving) MER. The bottom half of the movie is lightly rinsed to let you see in the shadows. The wheel on the left side of the movie (RR or LR??) gets buried and 'appears' to end up at an awkward angle... or it could just be an illusion of sand heaped-up over the wheel.

http://www.flickr.com/photos/30904379@N07/...679690/sizes/o/

Cheers
fredk
A bit of new info on how the tests are going in this latest free Spirit update:
QUOTE
Some of the tests in a JPL sandbox simulating Spirit's predicament have moved the test rover slightly -- on the order of a centimeter, or half an inch, of shift in position. This position change was achieved after enough wheel turns to have driven the rover the equivalent of tens of meters or yards on firmer ground.
MahFL
In the meantime I think there are 4 dustdevils in this image.

djellison
Remember - JPL Ustream event about getting Spirit out - tonight at 11pm UK, (so two hours time from now)

http://www.ustream.tv/channel/nasajpl
PDP8E
Anyone want to synopsize the Ustream event (for the stuck in traffic and just got home people!)
any new news?

cheers
centsworth_II
QUOTE (PDP8E @ Jul 23 2009, 06:04 PM) *
...any new news?

New to me... first try on Mars may be end of first week in August.

edit: Changed "probably" to "may be".
briv1016
There re-doing some of the tests with a firmer simulant under the right wheels. The latest update also summarizes it.

http://marsrovers.jpl.nasa.gov/mission/sta...ll.html#sol1968
HughFromAlice
QUOTE (PDP8E @ Jul 24 2009, 08:34 AM) *
Anyone want to synopsize the Ustream event ?


I managed to catch a few fair bits of it (it was start of worktime here so I was doing work things too!). There were others (like Doug) there who can fill you in better than me, but I have a few minutes at lunch, so...........

The most important overall impression I got was that that John Callas and the lady rover driver (apologies - but can't recall her name just at this minute) were cautiously upbeat. The LRD said quite specifically that there was a 'good' chance of getting Spirit out ............So here's hoping!!!

There were a lot of qs that UMSFers would be familiar with from this thread and the FREE SPIRIT - Extraction FAQs.

Good on NASA for doing this sort of thing.
JayB
I'm guessing Ashley Stroupe = LRD

does anyone know if there's an archive of this somewhere for the stuck in traffic group
CosmicRocker
It's archived on Ustream. Go to the webcast link that Doug provided. You'll find the video archived in two parts under the "related videos" links.
PDP8E
Thanks Cosmic!
climber
It looks like a little fish is coming into MI's field of view:
Click to view attachment
nprev
Nice little summary article on SpaceflightNow about extraction efforts to date.
Tesheiner
It's a very good recollection, although I almost posted an entry on the "Inaccuracy" thread after reading:

"Spirit has six wheels, but its forward right wheel has been frozen and unable to roll for three years... Even with this handicap it still climbed an 800 ft. tall mountain on Mars in October 2005." (emphasys is mine)
Floyd
"The frozen wheel has also resulted in the discovery of water related soil types, since that wheel is continuously creating a 3-4 inch deep trench behind the spacecraft".

Most of the time the trench has been about 1/2 inch deep. The dusty covering layer is often very thin and removing even a 1/2 inch exposes something interesting.
nprev
Yeah, there were a couple of flubs for sure; also noticed panel cleaning attributed to a DD. Still, always happy to see the crew get some coverage...FREE SPIRIT!!! smile.gif
CosmicRocker
Well, we never heard anything officially, but that last cleaning event, animated by Fran, just may have been a hit by a dust devil.

To add to the list of inaccuracies, I also noticed the SFN article contained this glaring error. (emphasis is mine)
QUOTE
It has so much electricity stored that it can weather the next winter without having to maneuver to a sun facing slope, Callas said.
We all know the battery could not possibly store enough power to carry the rover through a Martian winter. Furthermore, I sincerely doubt Callas would have said so. What the author should have said was that the recently cleaned solar panels are able to store enough energy each sol that the rover will be able to survive the next winter without acquiring an optimal, sun-facing slope.
climber
QUOTE (Tesheiner @ Jul 27 2009, 12:17 AM) *
It's a very good recollection, although I almost posted an entry on the "Inaccuracy" thread after reading:

"Spirit has six wheels, but its forward right wheel has been frozen and unable to roll for three years... Even with this handicap it still climbed an 800 ft. tall mountain on Mars in October 2005." (emphasys is mine)

Eduardo,
I don't think it's totally wrong. Reading Scott's "Mars and me" blog, it seams that the weel was used at 10% nearly from the foot of Columbia hill.
I guess it was then an handicap which turned to discoveries. I don't argue but, this is may be the reason of the statment. What do you think?
Tesheiner
I've been following Scott's blog too. The problem with the RF wheel currents was there since those days/sols and, as a way to mitigate the problem, it was actually used in such a mode (10% driving / 90% dragging) but, AFAIK, that driving mode was not used while climbing HH.
My "problem" with the wording in that otherwise really good report is that the handicap it states refers to a stuck wheel and not to the high currents.
brellis
Do the odds against getting unstuck go up as more time goes by? Has the depth of immersion changed noticeably since Spirit first got stuck?

Or, to put it more simply, is Spirit sinking at all?

Apologies if this was answered already.
fredk
Spirit hasn't sunk perceptibly. But it's interesting to look at the changes around her wheels since she became embedded. Compare these fhazcams from sols 1908 and 1967:
http://marsrovers.jpl.nasa.gov/gallery/all...DOP1214L0M1.JPG
http://marsrovers.jpl.nasa.gov/gallery/all...E5P1110L0M1.JPG
You can see many changes in the dug up soil, presumably from landslides and wind action. A long stretch of the exposed steep edge has caved in. A significant cap of dust on the LF wheel appears to have been blown away.

Similar changes happened behind Spirit:
http://marsrovers.jpl.nasa.gov/gallery/all...DOP1314R0M1.JPG
http://marsrovers.jpl.nasa.gov/gallery/all...E5P1314R0M1.JPG
This is a "lo-fi" version of our main content. To view the full version with more information, formatting and images, please click here.
Invision Power Board © 2001-2024 Invision Power Services, Inc.