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Unmanned Spaceflight.com _ Spirit _ Extricating Spirit

Posted by: briv1016 Nov 7 2009, 04:13 PM

5 downsampled navcam frames from sol 2078 are down. Someone might want to make an animation. wink.gif

Posted by: fredk Nov 7 2009, 04:35 PM

Holy $%@#! Wheels are spinning!
Sol 2072:
http://qt.exploratorium.edu/mars/spirit/rear_hazcam/2009-11-01/2R310307055EFFB200P1314R0M1.JPG
Sol 2078:
http://qt.exploratorium.edu/mars/spirit/rear_hazcam/2009-11-07/2R310840313EFFB203P1304R0M1.JPG
wheel.gif Spirit wheel.gif

Posted by: Tesheiner Nov 7 2009, 04:37 PM

QUOTE (briv1016 @ Nov 7 2009, 05:13 PM) *
5 downsampled navcam frames from sol 2078 are down. Someone might want to make an animation. wink.gif

Here is it.

Originals: http://qt.exploratorium.edu/mars/spirit/navcam/2009-11-07/

I thought they were still dealing with the flash memory problems...

Posted by: Stu Nov 7 2009, 04:41 PM

Go on girl, you can do it... smile.gif wheel.gif wheel.gif wheel.gif wheel.gif

Posted by: centsworth_II Nov 7 2009, 04:47 PM

QUOTE (Tesheiner @ Nov 7 2009, 11:37 AM) *
I thought they were still dealing with the flash memory problems...

I guess Spirit can walk and chew gum at the same time. smile.gif
Great to see those moving pictures!

Posted by: Tman Nov 7 2009, 04:52 PM

Yikes! ...ok, keeping fingers crossed!

Posted by: ups Nov 7 2009, 04:57 PM

Here we go...

wheel.gif

Posted by: fredk Nov 7 2009, 04:57 PM

I guess this is what Maxwell meant by his http://twitter.com/marsroverdriver/status/5484999771

QUOTE
Squyres: "It's gonna be a long day in the jarosite mines today."

Posted by: alan Nov 7 2009, 05:51 PM

Go Spirit Go

wheel.gif wheel.gif wheel.gif
wheel.gif wheel.gif


Posted by: SFJCody Nov 7 2009, 05:56 PM

QUOTE (fredk @ Nov 7 2009, 04:57 PM) *
I guess this is what Maxwell meant by his http://twitter.com/marsroverdriver/status/5484999771


Surely that must have been an Opportunity reference.

Posted by: centsworth_II Nov 7 2009, 06:10 PM

QUOTE (SFJCody @ Nov 7 2009, 12:56 PM) *
Surely that must have been an Opportunity reference.

The jarosite reference doesn't necessarily narrow it down, but it seems like Oppy approaching yet another(!) mystery rock is just another day in Meridiani and not worthy of special comment by SS.

edit: Or, perhaps the comment is just in reference to the fact that for the first time in a long time both rovers will be moving. Or, SS says that all the time and Scott just decided to make note of it today. Such is the trouble with interpreting cryptic remarks (or cryptic postings of ordinary remarks). laugh.gif

Posted by: imipak Nov 7 2009, 06:55 PM

Great to see motion at the first attempt, and hopefully encouraging for the outcome. ISTR at Purgatory progress was glacial for many days. I wonder if/when/how often further MI imaging of the possible contact rock underneath Spirit will be done. Perhaps they might not be needed at all..?

Posted by: Tesheiner Nov 7 2009, 07:04 PM

QUOTE (imipak @ Nov 7 2009, 07:55 PM) *
I wonder if/when/how often further MI imaging of the possible contact rock underneath Spirit will be done. Perhaps they might not be needed at all..?

One mars bar that they will image it again right after this first move.

Posted by: sgendreau Nov 7 2009, 07:09 PM

QUOTE (Tesheiner @ Nov 7 2009, 08:37 AM) *
Here is it.



Come on, hon. Come on....

Posted by: imipak Nov 7 2009, 07:23 PM

Animation of the left rear hazcams...


Posted by: Hungry4info Nov 7 2009, 07:37 PM

*crosses fingers*

Please... please... get out of that crap!

Edit: What sol are these images from? I'm at http://marsrovers.nasa.gov/gallery/all/spirit.html , and I'm not seeing the images you guys are posting.

Posted by: Sunspot Nov 7 2009, 07:48 PM

QUOTE (Hungry4info @ Nov 7 2009, 07:37 PM) *
Edit: What sol are these images from? I'm at http://marsrovers.nasa.gov/gallery/all/spirit.html , and I'm not seeing the images you guys are posting.


Spirit Images http://qt.exploratorium.edu/mars/spirit/

Oppy Images: http://qt.exploratorium.edu/mars/opportunity/

Posted by: fredk Nov 7 2009, 08:03 PM

Here's a gamma-tweaked animation of the right rear hazcams from 2072 and 2078:


You can see the LR wheel has been steered more straight, and presumably driven as well. Can't see the RR wheel. Front hazcams show RF wheel was steered straight as well.

I also would expect underbelly MI imaging. And also pancam images of the middle wheels.

Posted by: nprev Nov 7 2009, 08:09 PM

Go, baby, go!!! Good luck, MER team! wheel.gif wheel.gif wheel.gif

Posted by: Hungry4info Nov 7 2009, 08:36 PM

Thanks, Sunspot. =)

Yeah, I'm sure they'll image the underneath.

Posted by: akuo Nov 7 2009, 11:25 PM

Another momentous moment for the rovers. Good luck to RoverDriver and rest of the team!

Posted by: lyford Nov 8 2009, 12:56 AM

I can't help but hear this in my mind while looking at the animated gifs....
http://www.sound-effect.com/track/hot-rod-2-revs-456/

Go Spirit and thanks to the team for all the hard work leading up to these days! wheel.gif wheel.gif wheel.gif wheel.gif

Posted by: HughFromAlice Nov 8 2009, 04:14 AM

Exciting to see at least some movement. It almost looks like we might be taking the forward option? From the data available it is hard to judge whether it is more probable that we will get out or not, but being an optimist I think we will eventually inch our way out in time to find a wintering place.

May interest some people ....... just posted a version 3 of the Sol 2002 (Aug21st) sunset movie on YouTube with the sun continuously tracking down to give a more realistic effect. Will do some final corrections/colour adjustments on a V4 soon.

http://www.youtube.com/watch?v=cZtWGy0XcCQ

or type into search:- mars august sunset v3

Posted by: fredk Nov 8 2009, 04:30 AM

http://twitter.com/marsroverdriver/status/5517522009 that this move only involved steering, not driving the wheels.

Posted by: Juramike Nov 8 2009, 04:33 AM

But we're movin'! It's all good!

Posted by: serpens Nov 8 2009, 07:25 AM

QUOTE (Juramike @ Nov 8 2009, 04:33 AM) *
But we're movin'! It's all good!


But it looks as if the LR wheel sank further. Given Maxwell's indication that only steering was involved is the downwards movement really good?

Posted by: Ant103 Nov 8 2009, 11:17 AM

Yes, she moves ! Happy to see that smile.gif

I think it miss the FHC anim between Sol 2078 and 2079. Done smile.gif.

 

Posted by: djellison Nov 8 2009, 11:26 AM

QUOTE (serpens @ Nov 8 2009, 07:25 AM) *
is the downwards movement really good?


We far far FAR too early in the extraction process ( step one of dozens and dozens and dozens of steps ) to say if it's good or not.

But it HAS started, and that's reason to be happy.

If you're going to be negative every time any motion doesn't correlate with your expectation of how things should or shouldn't go, you're going to go very very mad, very very quickly.

Posted by: alan Nov 8 2009, 02:18 PM

Downward movement when steering only would be expected as that's what happened when it was done previously (before they attempted a turn in place)

I recall roverdriver mentioned testing spinning the wheels while steering was tested to determine if it reduced the downward movement.

Posted by: fredk Nov 8 2009, 05:03 PM

So RF and LR wheels were steered on 2078, and now LF and RR wheels steered on 2079. It's really hard to see what's happened with the RR, but if you compare the 2078 and 2079 images:
http://qt.exploratorium.edu/mars/spirit/rear_hazcam/2009-11-07/2R310840313EFFB203P1304R0M1.JPG
http://qt.exploratorium.edu/mars/spirit/rear_hazcam/2009-11-08/2R310928775EFFB204P1314R0M1.JPG
the soil behind the RR has moved quite a bit, perhaps looking as if the RR was actually driven. But my guess is it was just steered like all the others.

This is definitely all good news - finally the extraction has begun! smile.gif

Posted by: BrianL Nov 8 2009, 07:49 PM

Given that we're already up near 1100 posts, perhaps time for a new thread to follow this process?

Posted by: imipak Nov 8 2009, 07:55 PM

I don't remember seeing any estimates of how far back along her path Spirit needs to move to have all five working wheels on solid ground. Does the thin crust over the bright, dusty material extend further back than the visible piles of powder excavated by the left hand wheels?

And - forgive me if this has been answered, I've searched but not been found it - do we know what the pale material actually is? Silica or sulphate salts, or something else?

(Edit: Found CosmicRocker / Paolo :

http://www.unmannedspaceflight.com/index.php?s=&showtopic=5999&view=findpost&p=142244"]http://www.unmannedspaceflight.com/index.p...st&p=142244

...which doesn't shed much light smile.gif )

Posted by: brellis Nov 8 2009, 08:16 PM

do they have cameras on the practice rovers? it'd be neat to see the p.o.v. of what they're planning to do, and how the view compares with the real deal on Mars.

Posted by: elakdawalla Nov 8 2009, 08:24 PM

QUOTE (BrianL @ Nov 8 2009, 11:49 AM) *
Given that we're already up near 1100 posts, perhaps time for a new thread to follow this process?

Done smile.gif

GO SPIRIT!!! wheel.gif wheel.gif wheel.gif wheel.gif wheel.gif wheel.gif

Posted by: erpol Nov 9 2009, 12:15 PM

I'm a bit late, but I saw this continuation thread just now.
I only wanted to say:

It's a little ol' rover from Pa-sa-de-na...
Go Spirit go, Spirit go, Spirit go.

(cfr. Beach Boys mid '60)

wheel.gif wheel.gif wheel.gif

Ciao,
Ermanno

Posted by: ustrax Nov 9 2009, 12:53 PM

Ahh Spirit, you beautiful amazing girl...I want to hug you! biggrin.gif
GO! wheel.gif wheel.gif wheel.gif

Posted by: briv1016 Nov 9 2009, 07:46 PM

Teleconference to be held on Thursday:
http://www.nasa.gov/home/hqnews/2009/nov/HQ_M09-214_Spirit_Stuck_telecon.html

Audio stream should be available here:
http://www.nasa.gov/news/media/newsaudio/index.html


Also, the tracking site is back up.

Posted by: ups Nov 9 2009, 11:43 PM

The server is going to lag with all the spinning wheel gifs.

wink.gif

Posted by: Hungry4info Nov 10 2009, 06:55 AM

QUOTE (ups @ Nov 9 2009, 05:43 PM) *
The server is going to lag with all the spinning wheel gifs.

Yeah isn't it great? the thread with the most spinning wheel gifs is for the rover that isn't going anywhere laugh.gif

Posted by: Oersted Nov 10 2009, 11:05 AM

Eppur si muove!

Posted by: Greg Hullender Nov 10 2009, 05:16 PM

QUOTE (Oersted @ Nov 10 2009, 03:05 AM) *
Eppur si muove!

I'm still waiting to hear the inquisition's report.

--Greg :-)

Posted by: centsworth_II Nov 10 2009, 07:20 PM

QUOTE (Tesheiner @ Nov 7 2009, 11:37 AM) *
I thought they were still dealing with the flash memory problems...
I guess they are...

Date extrication starts isn't quite certain, but happening very soon. Want to fix "amnesia events" first if we can.
http://twitter.com/MarsRoverDriver

Posted by: Stu Nov 11 2009, 07:30 AM

Scott's latest Tweet:

" On Nov 12, there will be a press conference on upcoming Spirit extrication. Expect news stories shortly after, everywhere. :-) "

Posted by: Hungry4info Nov 11 2009, 09:16 AM

What time?

Posted by: Astro0 Nov 11 2009, 09:31 AM

What time? NASA will host a media teleconference at 1 p.m. EST on Thursday, Nov. 12, to discuss attempts to free the Mars rover Spirit from sandy soil where the venerable robot has been stuck for the past six months.

Posted by: JayB Nov 11 2009, 03:18 PM

"Expect news stories shortly after, everywhere. :-) "

If it wasn't for the smiley at the end, that statement would make me very nervous.


Posted by: stevesliva Nov 11 2009, 03:24 PM

It's a reasonable expectation that you will see headlines about NASA trying to rescue a "$300M rover" that has been "stuck for six months."

NASA and "problem" draws the press like flies on [a banana].

Posted by: briv1016 Nov 11 2009, 03:34 PM

$400 million.

Posted by: centsworth_II Nov 11 2009, 07:37 PM

QUOTE (JayB @ Nov 11 2009, 10:18 AM) *
"Expect news stories shortly after, everywhere. :-) "

If it wasn't for the smiley at the end, that statement would make me very nervous.
That comment is for the very general public. I would be surprised if there is anything new to readers of the UMSF Spirit thread. It doesn't look like there will even have been any additional action (since the steering movements) taken by Spirit before the briefing.

Posted by: Tesheiner Nov 11 2009, 08:42 PM

I would love to know what's behind the "backup plan" in http://twitter.com/marsroverdriver/status/5610436164: Paolo, Ashley, & I talked w/Chris Voorhees, genius designer of MER's mobility system, today. Helped us re-eval one backup plan.

Posted by: centsworth_II Nov 11 2009, 09:20 PM

QUOTE (Tesheiner @ Nov 11 2009, 03:42 PM) *
I would love to know what's behind the "backup plan"....[/i]
I guess the backups are plans that didn't make the cut for primary.

Posted by: nprev Nov 11 2009, 09:27 PM

I'm curious, too, though won't be surprised if there are several backup plans. Lots of lessons learned from TeeBee, I'm sure.

Posted by: Astro0 Nov 12 2009, 02:54 AM

MIs following the recent wheel moves.
Animation between sols 2076 and 2081.


Posted by: fredk Nov 12 2009, 05:07 AM

QUOTE (imipak @ Nov 8 2009, 08:55 PM) *
I don't remember seeing any estimates of how far back along her path Spirit needs to move to have all five working wheels on solid ground. Does the thin crust over the bright, dusty material extend further back than the visible piles of powder excavated by the left hand wheels?

Presumably she needs to get away from the crater that she's dug into. And we finally have a map showing the outline of Scamander crater ("Scamander plains"), with the http://marsrovers.jpl.nasa.gov/mission/tm-spirit/spirit-sol2081.html

With the crater taking up a sizable stretch of the middle of West Valley, I wonder what the approach would be if we drove out of Troy forwards (northwards). Would they continue to VB/G east or west of Scamander?

Posted by: Tesheiner Nov 12 2009, 06:51 AM

QUOTE (Astro0 @ Nov 12 2009, 03:54 AM) *
MIs following the recent wheel moves.
Animation between sols 2076 and 2081.

IMO, it is touching the underbelly. Actually, it's being dislodged by the rover's movement since there is a slight movement of the rock (clockwise orthogonal to the camera pointing).

Posted by: nprev Nov 12 2009, 06:57 AM

Sure hope you're right, Eduardo. If that thing's at all mobile, it shouldn't be a factor in the extraction after all.

Posted by: climber Nov 12 2009, 09:01 AM

QUOTE (fredk @ Nov 12 2009, 06:07 AM) *
With the crater taking up a sizable stretch of the middle of West Valley, I wonder what the approach would be if we drove out of Troy forwards (northwards). Would they continue to VB/G east or west of Scamander?

Now that we know of Scamander, we can see it... but we didn't before been stucked. I think I can see more crater-like features ahead in the 5.4Mb route map. Assuming Troy is "inside" a crater, I'll choose to drive on the "rims" of the craters to come whatever main direction will be selected.
This means will have to field prove that what we can see from MRO is what we actually can predict from Navcam & Pancam picts.
I'll be intersted to know if you see crater-like features ahead as I do.

Posted by: Tesheiner Nov 12 2009, 09:39 AM

QUOTE (nprev @ Nov 12 2009, 07:57 AM) *
Sure hope you're right, Eduardo. If that thing's at all mobile, it shouldn't be a factor in the extraction after all.

To be fair, now I'm not so sure about it. unsure.gif
I see movement on that rock but it might be also an illusion due to the shadows or compression artifacts.

Posted by: fredk Nov 12 2009, 03:10 PM

Yeah it looks to me like the perspective has changed a bit and everything under the rover has shifted over a bit, with belly rock staying in place relative to everything else. Hard to be sure though.

In terms of the press briefing, I don't think we've heard definitely what the primary extraction plan is. That would be something to listen for.

Posted by: climber Nov 12 2009, 05:44 PM

QUOTE (Astro0 @ Nov 11 2009, 10:31 AM) *
What time? NASA will host a media teleconference at 1 p.m. EST on Thursday, Nov. 12, to discuss attempts to free the Mars rover Spirit from sandy soil where the venerable robot has been stuck for the past six months.

Any link to this since it'll be in about 15 mn?

Edited, here it is: http://www.nasa.gov/home/hqnews/2009/nov/HQ_M09-214_Spirit_Stuck_telecon.html

Posted by: Stu Nov 12 2009, 05:47 PM

http://www.nasa.gov/news/media/newsaudio/index.html

Posted by: fredk Nov 12 2009, 05:50 PM

Great new topographic map of Scamander Crater at the very bottom of the list of briefing images:
http://www.nasa.gov/mission_pages/mer/news/telecon/tel20091110.html

Posted by: sgendreau Nov 12 2009, 06:32 PM

A synopsis of anything new would be much much appreciated by we who can't access at work. smile.gif

Go, Spirit, go, Spirit, go Spirit go!

Posted by: climber Nov 12 2009, 06:33 PM

Most single stricking picture of the conf:




Edited, sorry Fredk, same image as your link but can't remove it now.

Posted by: Stu Nov 12 2009, 06:42 PM

Emily's Tweeting it...

"What mired Spirit: left wheels broke through duricrust covering soft-sand-filled crater. Right wheels outside crater. "

Posted by: briv1016 Nov 12 2009, 06:43 PM

Flash was successfully reformatted yesterday; first drive command is Monday/Tuesday.

Posted by: Stu Nov 12 2009, 06:45 PM

Spirit MIGHT be stuck here for good...

Monday = drive attempt

Efforts to continue until Feb when there's a review...

Plan = follow tracks back out...

1st drive Mon: plan = 5m worth of wheel turns... commands sent Mon night/Tues a.m, data due back later Tuesday...

Posted by: Stu Nov 12 2009, 06:47 PM

"Still a lot of science can be done at this location..."

"Ability to do crude seismometry..."

Posted by: PDP8E Nov 12 2009, 06:50 PM

1st attempt: straighten out the wheels and then drive out in the ruts Spirit made on the drive in; start Late Monday / Early Tuesday (jpl time?), get info back: Tuesday

then take a day to see what is going on and re-plan...

Its going to be really exciting around here over the next week or two!

Cheers


Posted by: nprev Nov 12 2009, 07:01 PM

Hmmm. That map of Scamander really says it all. They pretty much have to try backing out. Sliding downslope is not an option, it's a rover-sized sand trap.

Re the wheel slewing: Is this Paolo's "sidewinder mode" (rotating the wheels while moving them from side to side)?

Posted by: climber Nov 12 2009, 07:05 PM

QUOTE (climber @ Nov 12 2009, 10:01 AM) *
Assuming Troy is "inside" a crater, I'll choose to drive on the "rims" of the craters to come whatever main direction will be selected.

It's basicaly what Ray Ardvinson's saying at this time !!!

Posted by: ustrax Nov 12 2009, 07:14 PM

What a Monday on the horizon... smile.gif
Cross your fingers until you get cramps!

Posted by: fredk Nov 12 2009, 07:20 PM

Some very interesting discussion of Belly Rock. One of the big concerns they have, which I hadn't heard before, was that the rock may get caught in one of a couple of notches or depressions on the belly. If it did, then presumably the rover would be stuck, if the rock was firmly embedded in the ground. They said the notches are a few cm in size, and that they are near the front edge of the belly. So that's another reason they want to drive forwards (northwards). If they backed up, the rock could get caught in one of the notches.

They also stressed they'll try to keep Belly Rock away from the rover centre of mass. But they didn't say where their MI imaging says the rock is now - closer to the front or the back. (Obviously near the back would be best.)

Other reasons for driving straight forwards are that going backwards would mean having to break through surface crust, so backtracking avoids that extra work. Also going backwards means climbing uphill.

Posted by: fredk Nov 12 2009, 07:30 PM

One more bit of info (which also appeared in a new http://www.newscientist.com/article/mg20427344.700-mars-rover-battles-for-its-life.html, was that with current dust levels, Spirit might just be able to survive another winter stuck in Troy. So another dust storm without any cleaning could do her in. Another good reason to get mobile.

Posted by: centsworth_II Nov 12 2009, 07:31 PM

Good briefing, lots of new details.

I liked the description of Spirit sitting right on a boundary between the highest sulfate level material found by either rover under the left wheel and basaltic material under the right wheel. The sulfur material being the soft, light material on the crater (down slope) side of the rover. Also the vertical changes from the surface of the duricrust to lower in the crust to beneath the crust showing water processes that occurred since volcanic activity in the area ceased.

I don't remember the danger of the belly rock being caught in a engineering depression in the underbelly being brought up before. One reason for driving forward rather than backward. I think that depression is visible in the underbelly images to the left of the belly rock's tip.

The detailed description of what occurred in the last days before halting driving operations was interesting. I found it encouraging that the (middle?) wheel stall seems to have not reoccurred when that wheel was tested. Also, the extraction maneuver, straight forward, is a maneuver that was not previously tried when the rover first became mired. A fresh maneuver leaves room for fresh hope... for me. Also good is the rover was still making progress when the driving was halted and was not just spinning its wheels. The progress was, however, in the down slope direction which is no longer considered a good idea, which is why the wheels were straightened for a straight forward drive.
edit: To clarify, the rover was going backwards toward Von Brun when it stopped. So a forward drive will be heading back in the direction it came from.


My fantasy: The wheels catch traction on some buried rocks and Tuesday morning images show the rover popped out and looking back at Belly Rock. laugh.gif

Posted by: nprev Nov 12 2009, 09:06 PM

Stories hitting Google News now; here's the Associated Press http://www.google.com/hostednews/ap/article/ALeqM5ilnj4NBQUmLXrtkuExcD8Uurx0DgD9BU74AG1, which usually serves as the root for derivative articles.

Posted by: ElkGroveDan Nov 12 2009, 09:27 PM

QUOTE
Spirit landed on Mars with six working wheels but soon lost movement in its right front wheel.

Typical media getting it wrong whenever they can.

Posted by: climber Nov 12 2009, 09:32 PM

Nasa comment regarding DM1 picture of today release was not much better (ok, probaly tiping mistakes)
"The red line tracks the 18.8 kilometers (11.7 miles) that NASA's Mars Exploration Rover Opportunity traveled from where it landed in January 2004 to its position 2,955 Martian days, or sols, later, on Nov. 4, 2009. The rover landed inside Eagle Crater and spent about half of its first year examining layers inside Victoria Crater before embarking on a long trek to the larger Victoria Crater, which is explored for two years."

Posted by: fredk Nov 13 2009, 01:27 AM

Now that we have these great maps of Scamander Crater, I went back and had a look for it in some old anaglyphs posted on this forum. And bingo: there, in Ant's sol 1869 pancam anaglyph mosaic from http://www.unmannedspaceflight.com/index.php?s=&showtopic=5901&view=findpost&p=138830 it is. Here's a crop with Scamander circled in white. Also I've circled in black the "rock garden" where we're currently sitting, with one side hanging over into the crater.


Posted by: Keatah Nov 13 2009, 03:00 AM

Why not flap the solar panels and fly away??

Posted by: Greg Hullender Nov 13 2009, 04:05 AM

QUOTE (Keatah @ Nov 12 2009, 07:00 PM) *
Why not flap the solar panels and fly away??

Feel free. :-)

--Greg

Posted by: centsworth_II Nov 13 2009, 04:19 AM

I'm wondering if the dark rectangle indicated by the arrow is the depression in Spirit's underbelly that they are concerned may catch on Belly Rock's tip. The forward drive, toward us as we view this image, is supposed to eliminate this possibility.


http://www.nasa.gov/mission_pages/mer/news/telecon/tel20091110.html

Posted by: nprev Nov 13 2009, 04:37 AM

Not to be denser than usual, but is anyone else getting terribly confused by the forward/back distinctions when talking about the extraction?

I propose establishing four standard reference terms: "rover-front", "rover-back", "rover-left", and "rover-right". Rover-front is the normal lead end of the vehicle where the IDD is mounted, and rover-back is obvious. Rover-left is the left side of the vehicle as viewed from above referenced to rover-front. Examples of useage: "Today Spirit moved 2m rover-back", "This MI image has rover-front facing the point of view", "Spirit experienced some slight rover-left slippage during today's drive".

Just a proposal, and in all probability there's already a perfectly good reference system that I'm not aware of.

Posted by: Astro0 Nov 13 2009, 05:24 AM

nprev, I know what you mean, but inevitably someone will abbreviate rover-front to RF and then were confused with wheel references like RF (right front) etc.

Spirit has been mostly driving 'backwards' for the past 3 years, so backwards is rear facing and forwards is front of vehicle (IDD end).

I just love acronyms of course, but I'd be happier if Spirit just G-O (got out!)

Posted by: nprev Nov 13 2009, 05:30 AM

Good point, Astro0, and I actually thought about that after posting. How about MER-xxx? Then we'd have MF, MB, ML, & MR.

(Boy; I have no life, do I?) rolleyes.gif tongue.gif

Posted by: centsworth_II Nov 13 2009, 05:35 AM

I like the fact that avoiding confusion forces the use of more descriptive language when describing a rover move.

Consider this a backlash against text message/tweeter speak. laugh.gif

Posted by: BrianL Nov 13 2009, 05:50 AM

I'll suggest arm-ward as the rover forward direction. I'll let someone else suggest a description for the other direction. biggrin.gif


Posted by: centsworth_II Nov 13 2009, 06:13 AM

Armward ho!


This situation does have a "Back to the Future" vibe, or in this case, Forward to the Past. laugh.gif

Posted by: climber Nov 13 2009, 07:18 AM

RF has a lot of traction here whatever RF means...

Posted by: Stu Nov 13 2009, 07:52 AM

That's a fascinating anaglyph Fred - you can almost convince yourself you can see the crater as a depression, can't you?

I guess it could have been a lot worse; if Spirit had driven further in, and not just sank in on one side, I think the game would already be over.

Posted by: SteveM Nov 13 2009, 01:43 PM

QUOTE (nprev @ Nov 13 2009, 12:30 AM) *
Good point, Astro0, and I actually thought about that after posting. How about MER-xxx? Then we'd have MF, MB, ML, & MR.

(Boy; I have no life, do I?) rolleyes.gif tongue.gif


Sailors long ago came up with names for vehicle-referenced directions: fore/forward and aft/astern, port and starboard. I've even heard port and starboard used for aircraft.

Steve M

Posted by: nprev Nov 13 2009, 01:46 PM

Yeah, thought about nautical terminology as well, and that'd be fine, too.

Anything would be fine as long as there was a consensus & consistent application.

Posted by: fredk Nov 13 2009, 03:33 PM

QUOTE (Stu @ Nov 13 2009, 08:52 AM) *
you can almost convince yourself you can see the crater as a depression, can't you?
I would say the crater is clearly visible - no convincing necessary! I was even able to match details of the size, shape, and topography with the contour map. Notice for example the "channel" running out of the crater to the NNW. (It shows up on the contour map as blue.) Look at Ant's original anaglyph to see it more clearly.
QUOTE
I guess it could have been a lot worse; if Spirit had driven further in, and not just sank in on one side, I think the game would already be over.

Exactly! I was thinking the same thing. Looking at those images, there's nothing (apart from the crater shape and hindsight) to suggest danger in the crater. I think the plan was to get over to the "sidewalk" beside HP, and that may have saved us from certain doom.

Posted by: Tman Nov 14 2009, 02:53 PM

QUOTE (HughFromAlice @ Nov 8 2009, 06:14 AM) *
May interest some people ....... just posted a version 3 of the Sol 2002 (Aug21st) sunset movie on YouTube with the sun continuously tracking down to give a more realistic effect. Will do some final corrections/colour adjustments on a V4 soon.

http://www.youtube.com/watch?v=cZtWGy0XcCQ

Sorry of the late reply. That's a nice idea. The moving sun looks very realistic.

Beside the colour adjustements you could yet implement the local true time generating with http://www.greuti.ch/oppy/html/filenames_ltst.htm smile.gif

Posted by: dshaffer Nov 14 2009, 05:14 PM

Does anyone know where I can find an mp3 file of the Nov 12 teleconference?

Posted by: HughFromAlice Nov 15 2009, 12:12 AM

QUOTE (Tman @ Nov 15 2009, 12:23 AM) *
colour adjustements ... local true time generating


Thanks Peter - good ideas and also going to do a few more things for v4. A sort of learning experiment!!! Did it away from home under time pressure and didn't have your v. useful corrected time page bookmarked on my favourites. But I have bookmarked it right now smile.gif.

Currently working on another Oppy navcam 'panorama' - Sol 2058. They are a real challenge and great fun to do.

Posted by: JayB Nov 16 2009, 05:06 PM

"@marsroverdriver Showtime! #FreeSpirit 3 minutes ago from Twitterrific"

wheel.gif wheel.gif wheel.gif

Posted by: Sunspot Nov 16 2009, 05:31 PM

We might see the first images at exploratorium in the next hour then.

Posted by: elakdawalla Nov 16 2009, 05:44 PM

IIRC at the press briefing they said the commands would be executed late Monday evening, Pasadena time -- or maybe that was when the downlink would happen. Perhaps "Showtime" referred to the uplink? Mars24 tells me it's now only 08:20 at Gusev, so they wouldn't be driving yet, right?

Edit: Blerg, I misread Mar24. As I write this it is indeed late evening Spirit time, 19:42. Sorry to add to the confusion.

Posted by: centsworth_II Nov 16 2009, 05:44 PM

QUOTE (Sunspot @ Nov 16 2009, 12:31 PM) *
We might see the first images at exploratorium in the next hour then.

The commands go up tonight, the pictures come down early Tuesday morning. I'm guessing this is all California time. Right now, http://marsrover.nasa.gov/home/index.html, so the rover still has a full night's rest ahead before the big day on Mars.

Posted by: Sunspot Nov 16 2009, 05:53 PM

confused blink.gif

Juggling 3 different time zones here

Posted by: centsworth_II Nov 16 2009, 05:56 PM

QUOTE (elakdawalla @ Nov 16 2009, 12:44 PM) *
...Perhaps "Showtime" referred to the uplink?
I'm guessing "showtime" refers to the whole atmosphere surrounding preparations for the EVENT. The pictures may be anticlimactic, but as others have said, a couple centimeters forward motion will be good news.

Posted by: centsworth_II Nov 16 2009, 06:02 PM

QUOTE (Sunspot @ Nov 16 2009, 12:53 PM) *
Juggling 3 different time zones here
If we knew what time Spirit was programmed to move, Spirit time, you could just check thehttp://marsrover.nasa.gov/home/index.html link I posted. Noon Spirit time is still almost 17 hours away. But I don't know if Spirit will move before or after that.

Posted by: elakdawalla Nov 16 2009, 06:08 PM

Sorry to have added to the confusion. It's now late evening Spirit time as centsworth pointed out; driving action can be expected at noon give or take a few hours Mars time, which is some time in the wee hours of the morning California time. Unconfused yet?

Posted by: Burmese Nov 16 2009, 07:38 PM

I imagine 'Showtime' meant the commands were transmitted. As for expected movement, I think they'll be happy to see a fraction of a centimeter and no drift in a bad direction.

Posted by: fredk Nov 16 2009, 08:17 PM

According to the http://www.nasa.gov/mission_pages/mer/news/telecon/trans20091112.html last week, the plan was (presumably California time):

QUOTE
we will be planning the first motion of the rover on Monday, as part of our normal tactical process for the rover... Those commands will go up Monday night. They will execute on the rover late Monday night, early Tuesday morning, and we should get the data down very early Tuesday morning.

My interpretation of "show time" is that Maxwell arrived at work and started working on the very important driving plan for Spirit. But I have to say it's a bit silly putting much effort into trying to "read the tealeaves", ie trying to decipher such cryptic posts.

Posted by: imipak Nov 16 2009, 11:12 PM

QUOTE (Sunspot @ Nov 16 2009, 05:53 PM) *
confused blink.gif
Juggling 3 different time zones here

That's what UTC is for wink.gif

According to @marssciencegrad, downlinks are set for:
QUOTE
06:40 PST Tues. Nov. 17th and 07:20 PST Wed. Nov. 18th


Which is to say,
CODE
2009-11-17 1440 UTC
and
CODE
2009-11-18 1520 UTC,
in ISO 8601 anyways smile.gif

Posted by: Floyd Nov 16 2009, 11:57 PM

This thread started when briv1016 noticed that the wheels had moved and the hazcam images changed. Tesheiner made the 5 image movie and we were off.

I think it would be great to have a thread--like the map thread--where just images are posted. We could all go there and see how Spirit has moved since starting the wheel turns. As lots of images may come come down with each drive day, the total number of hazcam & other images could get really large. So maybe one movie where only the final frame of each day's effort gets added to the end of the movie.

Since I don't have image/movie skills, I am not not the one to start the new thread: Spirit Escape--the Movie. But maybe someone who could make such movies could start such a thread. smile.gif

This thread should definitely continue for all of its great discussions (and images).

Posted by: Astro0 Nov 17 2009, 12:04 AM

Like the extrication process is going to be, a movie will be painstakingly wheel.gif SLOW wheel.gif wheel.gif.
I'm sure that someone will do a movie, but a long way into the process/progress. Not really worth a new thread, just occasional updates here.

Posted by: brellis Nov 17 2009, 12:12 AM

Are there hazcam pics from the test rovers going thru the planned maneuvers?

Posted by: briv1016 Nov 17 2009, 02:45 AM

Small blurb about the upcoming drive:

http://marsrovers.jpl.nasa.gov/spotlight/20091116a.html


Also, the tracking site has the planned imaging sequence for sol 2088.


Edit: Thanks Astro. cool.gif

Posted by: Astro0 Nov 17 2009, 10:33 AM

I hadn't seen these mentioned elsewhere in this thread.
Check out this from http://www.youtube.com/user/JPLraw video on http://www.youtube.com/watch?v=5WEcMC6LGtY.

The 7min38sec NASA B-roll video contains:
Video of JPL engineers in MER testbed and in a meeting discussing the extrication tests
Various images showing where Spirit is stuck, underbelly view and local terrain
Some interesting interview segments with Ashley Stroupe
Extra images and animation of Spirit's journey, current location, maps etc.

brellis asked: Are there hazcam pics from the test rovers going thru the planned maneuvers?
There's a very quick shot from TeeBee's FrontHazcam showing some 'downhill' movement.

All-in-all some interesting stuff to watch while we wait for new images from Spirit.

Posted by: Hungry4info Nov 17 2009, 01:35 PM

I'll see about building a movie over time as this whole thing unfolds.
Can anyone suggest a way to convert .gif files into something usable by YouTube? (.flv)

Posted by: AndyG Nov 17 2009, 01:58 PM

Flash would seem to be the best way to import gifs and export flv. Adobe do a free thirty-day trial if you want to experiment.

Andy

Posted by: djellison Nov 17 2009, 02:03 PM

Youtube will actually take almost anything, and convert it itself. Perhaps Quicktime Pro ( load an anim gif, export to H264 .mob - then upload to youtube)


next bit isn't aimed at you directly.


This is a warning. Progress today may be negligible, it may be significant, it may be entirely invisible and non existent.

DO NOT attempt to draw too many conclusions, positive or negative, regarding the efficacy of the technique, the likelihood of a final extraction and so on. People using words like 'never' or 'certain' or 'wrong' will have firm forum wrist slappings.

Many of you were not around during the month of extraction at Purgatory Ripple. The old hands know how frustrating this process is going to be. Be patient. Do not jump to conclusions. Do not resort to superlatives.

Warning over.


As you were.

Posted by: Ant103 Nov 17 2009, 02:45 PM

Thanks for the link to the vidéo Astro0, I'll be watching it wink.gif.

Posted by: jamescanvin Nov 17 2009, 03:39 PM

Some data on the tracking site now!

Movement of a few tenths of a mm according to that data (don't read too much into this!)

edit:
Looks like the drive number has only be incremented by 'one'. I was expecting at least two as the drive was in two legs + maybe more as there were visdom navcam images sequenced.

Possible aborted drive?

Posted by: fredk Nov 17 2009, 03:43 PM

QUOTE (imipak @ Nov 17 2009, 12:12 AM) *
According to @marssciencegrad, downlinks are set for:
2009-11-17 1440 UTC

That's the same time that images have been showing up on exploratorium (as well as a few other times during the day). None showed up at 1440 today. Does anyone know what the timing is like here - when does a downlink at 1440 typically show up on exploratorium? (I thought it was fast?) Could it be there was data returned but no full images?

Posted by: Tesheiner Nov 17 2009, 03:52 PM

> Movement of a few tenths of a mm

Actually, a few mm. smile.gif (Edited)

Fredk, regarding the downlink time, I think that 1440UTC was the beginning of the downlink session so it missed the data transfer to the exploratorium by a small amount of time. We may see the pictures in the next window which will be at 2040UTC.

Posted by: Tesheiner Nov 17 2009, 04:01 PM

QUOTE (jamescanvin @ Nov 17 2009, 04:39 PM) *
Possible aborted drive?

Don't think so.
The rationale (my assumption) is that in that case the imaging sequence that would be triggered would be "front_hazcam_fault_pri15_4bpp" instead of "front_hazcam_ultimate_4_bpp" and the seqid corresponds to the latter.

...
02088::p1214::05::2::0::0::2::0::4::front_hazcam_ultimate_4_bpp
02088::p1235::00::2::0::0::2::0::4::front_hazcam_0.5bpp_pri_18
02088::p1247::03::2::2::0::0::0::4::frHC_mega_cleatcam_half_2_bpp_pri_26
02088::p1254::00::2::0::0::2::0::4::front_hazcam_fault_pri15_4bpp
02088::p1314::00::2::0::0::2::0::4::rear_haz_ultimate_4bpp_pri15
02088::p1335::00::2::0::0::2::0::4::rear_hazcam_0.5_bpp_pri_18
02088::p1347::03::2::2::0::0::0::4::RearHC_mega_cleatcam_half_2_bpp_pri_26
02088::p1354::01::2::0::0::2::0::4::rear_haz_fault_pri15_4bpp
...

Posted by: jamescanvin Nov 17 2009, 04:11 PM

QUOTE (Tesheiner @ Nov 17 2009, 03:52 PM) *
Actually, a few mm. smile.gif


Really? I originally wrote mm in the post but then calculated that the change from yestersol to tosol was only 0.21mm E/W 0.58mm N/S (I can't remember off hand the directions). Your the expert at this these days so I hope your right. smile.gif

QUOTE (Tesheiner @ Nov 17 2009, 04:01 PM) *
The rationale (my assumption) is that in that case the imaging sequence that would be triggered would be "front_hazcam_fault_pri15_4bpp" instead of "front_hazcam_ultimate_4_bpp" and the seqid corresponds to the latter.


Thanks, I hadn't appricated that logic before.

Posted by: fredk Nov 17 2009, 04:27 PM

QUOTE (jamescanvin @ Nov 17 2009, 05:11 PM) *
0.21mm E/W 0.58mm N/S

Could someone remind us what exactly these numbers are based on? Integrating the accelerometers? Visodom?

Posted by: djellison Nov 17 2009, 04:36 PM

Unless I'm very much mistaken (and that's quite likely) - it's IMU based.

Posted by: Tesheiner Nov 17 2009, 04:54 PM

QUOTE (jamescanvin @ Nov 17 2009, 05:11 PM) *
Really? I originally wrote mm in the post but then calculated that the change from yestersol to tosol was only 0.21mm E/W 0.58mm N/S (I can't remember off hand the directions). Your the expert at this these days so I hope your right. smile.gif


You are right! I got wrong numbers for the pre-drive position.

Posted by: Tesheiner Nov 17 2009, 05:09 PM

QUOTE (fredk @ Nov 17 2009, 05:27 PM) *
Could someone remind us what exactly these numbers are based on? Integrating the accelerometers? Visodom?


AFAIK, it's both.
If visodom is not used, the rover's position is updated solely with the IMU data.
If visodom is used, and this is the case for the current drive, the position is calculated (my guess) as follows:
1. A step is executed in "blind" mode and the position updated with IMU info.
2. A navcam shot is taken and processed by the visodom logic and a corrected position is determined.

Posted by: centsworth_II Nov 17 2009, 05:10 PM

QUOTE (jamescanvin @ Nov 17 2009, 11:11 AM) *
...0.21mm E/W 0.58mm N/S...
Are these numbers statistically significant? What about stress and temperature related changes (noise)?

Posted by: jamescanvin Nov 17 2009, 05:12 PM

I'm pretty sure that they are from the IMU.

I really don't know what signifcance to put on these very small numbers. My gut feeling is not a lot!

Posted by: elakdawalla Nov 17 2009, 05:44 PM

Just a fact check here -- was sol 1898 the last sol on which Spirit rolled wheels in a commanded drive? It seems like there's a more recent driving day that I'm missing.

Posted by: PhilCo126 Nov 17 2009, 07:15 PM

Correct, Spirit got dug in on 6th May 2009 (sol 1899) wheel.gif wheel.gif wheel.gif

Posted by: jamescanvin Nov 17 2009, 07:38 PM

I think it is a bit of a stretch to say Spirit got 'dug in' on 1899 - the problems started on sol 1886 and she was furthest 'in' on 1891.

Emily, the last significant drive was on 1898. There was a drive with very little movement on sol 1899 which I think was the one that faulted out when the middle wheel stalled.

James

Posted by: elakdawalla Nov 17 2009, 07:41 PM

Thank you both!

(F5, F5, F5, F5...still looking for those raws!)

Posted by: fredk Nov 17 2009, 07:45 PM

As Tesheiner wrote above, the jpegs shouldn't appear at exploratorium until around 20:40 UT. If not then, add n*6 hours, for integer n.

Posted by: Sunspot Nov 17 2009, 07:46 PM

The exploratorium site must be broken again

Posted by: Tesheiner Nov 17 2009, 08:30 PM

It's still 20:30UTC per my account. rolleyes.gif

UTC = GMT = ZULU

Posted by: fredk Nov 17 2009, 08:41 PM

Right on cue, the images are up at exploratorium:
http://qt.exploratorium.edu/mars/spirit/forward_hazcam/2009-11-17/2F311735004EFFB205P1214R0M1.JPG
http://qt.exploratorium.edu/mars/spirit/rear_hazcam/2009-11-17/2R311735481EFFB205P1314R0M2.JPG
Looks indeed like very small movement.

Posted by: briv1016 Nov 17 2009, 08:43 PM

Where did you guys find that time BTW?

Posted by: Tesheiner Nov 17 2009, 08:50 PM

The explotratorium is sync'ed four times a day at 0240, 0840, 1440 and 2040 UTC.
It's not posted anywhere, it's just a question of checking for new data day after day since some years ago. smile.gif

Posted by: Tesheiner Nov 17 2009, 08:57 PM

Back to business, to our "armchair analysis"...

I believe I can see the "two steps" of today's drive on the tracking web data. If that's correct, it's a little bit different from previous extraction moves since it's completely embedded on a single "site/drive id" (if you know what I mean). Assuming the commanded wheel turns were as reported on the MER website (2.5m each step), the slip factor was really high, as expected: 99.98 - 99.99%

Posted by: fredk Nov 17 2009, 08:57 PM

Do you mean the 20:40 time? I've just noticed that the exploratorium images have been appearing four times a day 6 hours apart. You can see that from the timestamps on the exploratorium files. Edit - Tesheiner was quicker than me!

I don't see much evidence of movement in the soil around the LF wheel, comparing before and after tosols drive attempt:
http://qt.exploratorium.edu/mars/spirit/forward_hazcam/2009-11-08/2F310928585EFFB204P1214R0M1.JPG
http://qt.exploratorium.edu/mars/spirit/forward_hazcam/2009-11-17/2F311735004EFFB205P1214R0M1.JPG
So should these new images be at the halfway mark, after 2.5 metres of wheel motion, or after 5 metres? The wheel treads have definitely moved, but is that 2.5 metres worth of change in the surrounding soil?

Peering into the shadows, there is some change in the soil behind the LR wheel:


Posted by: Tesheiner Nov 17 2009, 09:11 PM

AFAIK, the images correspond to the end of the drive.

Posted by: djellison Nov 17 2009, 10:15 PM

Fred - your anim is good - I think we see the RR wheel digging in a reasonable amount, not much movement on the LR.

Posted by: mhoward Nov 17 2009, 11:24 PM

Don't know what it tells us, if anything, but here's two images to compare the left middle wheel between Sol 2008 and Sol 2088.

Edit: Ugh; those show up in reverse order, and without the filenames - yech. If you switch between these images, it looks like the left middle wheel has raised a bit (not sunk). If you save the images to your computer they should have more illuminating filenames.

 

Posted by: mhoward Nov 17 2009, 11:25 PM

And for completeness, here's the right middle wheel, sol 2012 and sol 2088.


 

Posted by: briv1016 Nov 17 2009, 11:29 PM

Apparently today’s drive only lasted 1 second.

http://www.jpl.nasa.gov/freespirit/index.cfm

Posted by: Astro0 Nov 17 2009, 11:30 PM

MIs from sol2076(2frames) and sol2088(1frame)
Animation - large movement was on sol 2076 when the wheels were re-aligned and last frame from today's movement.
Lined up as best as I can for now.



3xMI pan...

Posted by: centsworth_II Nov 18 2009, 12:04 AM

QUOTE (briv1016 @ Nov 17 2009, 06:29 PM) *
Apparently today’s drive only lasted 1 second.

laugh.gif
I thought the post drive results would be anticlimactic, but not THAT anticlimactic!

Posted by: ElkGroveDan Nov 18 2009, 12:14 AM

QUOTE (briv1016 @ Nov 17 2009, 03:29 PM) *
Apparently today’s drive only lasted 1 second.

http://www.jpl.nasa.gov/freespirit/index.cfm


That can't be accurate. My understanding is that the instructions were for a drive of 2.5 meters. Now regardless of whether the rover actually moved, the wheels were instructed to turn accordingly. So if a 1.0s duration is accurate then that's a speed of 2.5 m/s. If I recall correctly that's about five times faster than the rover's top speed of 0.5 m/s.

EDIT: Never mind. I see there was a premature shut down due to the tilt.

Posted by: pac56 Nov 18 2009, 12:20 AM

QUOTE (Astro0 @ Nov 17 2009, 06:30 PM) *
MIs from sol2076(2frames) and sol2088(1frame)
Animation - large movement was on sol 2076 when the wheels were re-aligned and last frame from today's movement.
Lined up as best as I can for now.


Very nice animation. If the rocks could be aligned and kept still, we could see the rover move.
PAC

Posted by: centsworth_II Nov 18 2009, 01:14 AM

"...The rover has a top speed on flat hard ground of 5 centimeters (2 inches) per second...."
http://marsrover.nasa.gov/mission/spacecraft_rover_wheels.html

Given a wheel diameter of 25cm (78.5cm circumference), full speed would turn the wheel about 6.3% of a revolution in one second.

Posted by: elakdawalla Nov 18 2009, 01:30 AM

I just have to comment that the last day's worth of posts on this topic must hit some kind of high for the ratio of analysis to driving distance. rolleyes.gif

Posted by: lyford Nov 18 2009, 01:40 AM

QUOTE
I just have to comment that the last day's worth of posts on this topic must hit some kind of high for the ratio of analysis to driving distance.


Time to update the map, Tesh? biggrin.gif biggrin.gif

Posted by: MarkG Nov 18 2009, 04:22 AM

Oh, what the heck, let's get wildly speculative...

1)
I would assert that today's movement was intentionally slight, a deliberate perturbation to confirm data on Spirit's mechanical and frictional state. This includes noting if the rock underneath is in significant contact (is it a pivot?). The response from this perturbational movement will help determine the next movement set. Mechanical engineers love perturbation theory. ...And the principal of virtual work...

2)
Digging myself deeper (not Spirit, hopefully), the JPL guys in the sand pit found a "stick-slip" type of behavior, so that a slight movement below a certain threshold (.5 mm?) would not cause the sandy dust under the wheels to break free and slip. Furthermore, the diurnal thermal cycle causes a "reset" of the grain inter-particle friction, so the slight stick-before-slip can be repeated the next Sol. So, we can expect Spirit to explode out of its hole at 1.5 cm/month.

3)
The right front wheel no longer turns, but it can be rotated left and right. In fact, if this is done while the other wheels are pushing, it reduces somewhat the effective drag that dead wheel provides. Helps Spirit shimmy out of there...

--There, now I feel better.

Posted by: centsworth_II Nov 18 2009, 05:05 AM

According to the update:

"A tight limit on vehicle roll and pitch of less than 1 degree change was set for this first drive. As the rover began its first move, it sensed that its roll was outside the allowed limit and safely stopped the drive."

Less than one degree pitch or roll. I don't think they expected the drive to last very long with those restraints -- a few seconds at the most.

The specific pitch or roll movement triggering an abort would give them some valuable information. According to the update it was a roll that shut the drive down. To the left or right? It seems that a roll to the right would be preferable, but then it would still need to be determined if it was because of the left wheels rising or the right wheels sinking.

Posted by: MahFL Nov 18 2009, 11:50 AM

Patience fellows.....the next drive will be huge...like 2 seconds......
wheel.gif wheel.gif wheel.gif

Posted by: MahFL Nov 18 2009, 11:51 AM

BTW, what was the normal tilt and roll limit, and the ultimate limits which would make it fall over ?

Posted by: Sunspot Nov 18 2009, 11:58 AM

Did the rovers tilt change during the drive attempt? I don't understand how the abort could have been triggered during the first second of the wheels turning. blink.gif

Posted by: jamescanvin Nov 18 2009, 12:55 PM

Sunspot,
My impression from the line:

"As the rover began its first move, it sensed that its roll was outside the allowed limit and safely stopped the drive."

Is that the roll of the vehicle was *already* out off allowable drive limits before even starting the drive. i.e there was a mismatch between the actual roll of the vehicle and what the drivers thought it was when setting the limits. As soon as the first roll limit check was made after the drive started, this was discovered and the drive stopped.

Posted by: centsworth_II Nov 18 2009, 01:03 PM

Using 145cm wheelbase and 1 degree angle I get 2.5cm* change in elevation from one side to the other. We don't know what the limit was set at, one half degree? One tenth? It's not hard to imagine a vehicle the size of Spirit settling one centimeter on one side as soon as its wheels start turning. No need for that to take one whole second.

*EDIT: correcting the wheelbase to 106cm, the calculation gives 1.85cm change in elevation.

Posted by: Astro0 Nov 18 2009, 01:10 PM

Not knowing which direction the tilt actually went at this stage (did someone work it out?), but...
...to visualise a full 1 degree tilt (the real tilt was less) in 1 second, here's a animation.



EDIT: 11 degree angle at start, rotating by 1 degree.

Posted by: MahFL Nov 18 2009, 01:11 PM

I got the impression it was 1 degree from where they were at, they already said she was at a small of degree roll on the edge of the crater didn't they ?

Posted by: Tesheiner Nov 18 2009, 01:23 PM

QUOTE (centsworth_II @ Nov 18 2009, 02:03 PM) *
Using 145cm wheelbase and 1 degree angle I get 2.5cm change in elevation from one side to the other. We don't know what the limit was set at, one half degree? One tenth? It's not hard to imagine a vehicle the size of Spirit settling one centimeter on one side as soon as its wheels start turning. No need for that to take one whole second.


The change in the Z-axis during the drive, measured by the rover itself, was only 1mm.

Posted by: djellison Nov 18 2009, 01:25 PM

A polite reminder repeated from earlier...

This is a warning. Progress may be negligible, it may be significant, it may be entirely invisible and non existent.

DO NOT attempt to draw too many conclusions, positive or negative, regarding the efficacy of the technique, the likelihood of a final extraction and so on. People using words like 'never' or 'certain' or 'wrong' will have firm forum wrist slappings.

Many of you were not around during the month of extraction at Purgatory Ripple. The old hands know how frustrating this process is going to be. Be patient. Do not jump to conclusions. Do not resort to superlatives.

Warning over.



Posted by: centsworth_II Nov 18 2009, 01:27 PM

QUOTE (MahFL @ Nov 18 2009, 06:51 AM) *
BTW, what was the normal tilt and roll limit, and the ultimate limits which would make it fall over ?

From the original press kit, way back when:
"The distribution of mass on the vehicle is arranged... to tolerate a tilt of up to 45 degrees in any direction without overturning, although onboard computers are programmed to prevent tilts of more than 30 degrees."


Spirit is now maybe 11 (12?) degree tilt after recent movements.

Posted by: centsworth_II Nov 18 2009, 01:41 PM

QUOTE (Tesheiner @ Nov 18 2009, 08:23 AM) *
The change in the Z-axis during the drive, measured by the rover itself, was only 1mm.

Interesting. We don't know what fraction of one degree tilt was set as a limit, maybe just a tenth of a degree.

Plugging in wheel base 145cm and tilt 0.1cm, I get an angle of 0.04* degrees. If the Z axis change is from the center of the wheel base, the total from one side to the other would be 2mm for close to a 0.1 degree change.

edit: Maybe Astro0 should adjust his animation so it's not so scary. smile.gif

*EDIT: correcting the center line wheelbase to 106cm, the angle is 0.054. Still approximately 0.1 degree total change.

Posted by: fredk Nov 18 2009, 04:10 PM

QUOTE (jamescanvin @ Nov 18 2009, 01:55 PM) *
My impression... Is that the roll of the vehicle was *already* out off allowable drive limits before even starting the drive. i.e there was a mismatch between the actual roll of the vehicle and what the drivers thought it was when setting the limits.

My original interpretation was that the change in roll after starting the drive exceeded the limit. But this quote from http://marsrovers.jpl.nasa.gov/spotlight/20091117a.html supports your conclusion:
QUOTE
From this limited drive the team now has a more accurate measurement of vehicle roll and pitch that will be used for subsequent drive planning.


Still, answering Centsworth's question from above, there definitely was a roll during the short drive attempt. Compare hazcams from 2088 and 2079. In both front and rear cases, the horizon tilts between 2079 and 2088, which means there was a roll. The direction of roll that causes that change in horizon tilt is down on Spirit's left side/up on her right side. My guess would be down on the left rather/more than up on right. So that means she's sunk a bit deeper into Scamander on her left.

But from those same hazcams you can also estimate the angle of the roll. In both cameras, the horizon rises by about 1 pixel on Spirit's left side from 2079 to 2088. It's unclear exactly what to take as the long arm of the rotation, plus there are significant distortions in these hazcameras, but that gives roughly a roll angle of 0.05 to 0.1 degree. That agrees surprizingly well with Centsworth's estimate of the roll based on the drop in z above.

One last comment that no one's made yet, before I blow Emily's analysis-to-drive-duration ratio completely through the roof: I definitely see the drive stopping prematurely as good news. The images showed very depressing progress had the drive proceeded for the planned 5 metres. But very little progress in less than one second is just fine. smile.gif

Posted by: Steve Holtam Nov 18 2009, 06:01 PM

Another armchair rover driver here. In that one second of "activity" I doubt the wheels turned even the 6.3% of one full rotation. I would guess the very cautious pitch threshold was reached the moment the wheels started to spin, and thus the movement was aborted. I'm thinking its an actual tilt vs. what JPL told the computers the tilt was abort. Either way, this is an easy fix.

Posted by: fredk Nov 18 2009, 07:05 PM

I think we can answer that. Looking carefully at the LF and LR wheels in the hazcams, we can identify features on the wheels (or in the powder caked on them) between sols 2079 and 2088:

It looks like the wheels turned only about half a wheel cleat. With 29 cleats all around, that gives a rotation of about 6 degrees, or about 1.7% of a full rotation. If 6.3% corresponds to one second at full speed, then this drive was about 1/4 second at full speed. Longer if slower.

Posted by: MahFL Nov 18 2009, 07:17 PM

"Progress ?" was there any forward progress, or did the wheels just spin ?

Posted by: tacitus Nov 18 2009, 07:31 PM

Given that they are expecting to drive many meters to get the couple of feet they need to get out of the trap, I think it's safe to say that the one second drive was all wheel spin, if such a minuscule turn can be called "spin"

Posted by: centsworth_II Nov 18 2009, 07:57 PM

QUOTE (fredk @ Nov 18 2009, 02:05 PM) *
....If 6.3% corresponds to one second at full speed, then this drive was about 1/4 second at full speed. Longer if slower.

Although full speed is quoted as 5 cm per second, according to http://www-robotics.jpl.nasa.gov/publications/Mark_Maimone/biesiadecki_maimone06.pdf "Straight line driving speed is set to 3.75 centimeters/second...." (page 2). Who knows what the speed was set to.

Posted by: marsophile Nov 18 2009, 08:32 PM

QUOTE (fredk @ Nov 18 2009, 09:10 AM) *
Still, answering Centsworth's question from above, there definitely was a roll during the short drive attempt. Compare hazcams from 2088 and 2079. In both front and rear cases, the horizon tilts between 2079 and 2088, which means there was a roll. The direction of roll that causes that change in horizon tilt is down on Spirit's left side/up on her right side. My guess would be down on the left rather/more than up on right. So that means she's sunk a bit deeper into Scamander on her left.


Are you sure about that? When I compare front hazcams from 2088 and 2079, I reach the opposite conclusion. Also, looking at the animation, it does not appear the LF wheel has sunk deeper; if anything, it seems (even after discounting the deceptive effect of the shadows) to have risen slightly.

Posted by: fredk Nov 18 2009, 08:58 PM

Pretty sure. Flip between the 2079 fhaz image:
http://marsrovers.jpl.nasa.gov/gallery/all/2/f/2079/2F310928585EFFB204P1214R0M1.JPG
and the 2088 image:
http://marsrovers.jpl.nasa.gov/gallery/all/2/f/2088/2F311735004EFFB205P1214R0M1.JPG
Make sure the images are aligned exactly (full screening both should work). Notice that the horizon along the left side of the image rises between 2079 and 2088. It's only by a tiny amount, around 1 pixel. If you try to picture the camera fixed to the rover, if the left (west) side of the rover sunk down a bit, you'd expect the left side of the horizon to rise a bit in the front hazcam view, and that's what we see.

I agree about the LF wheel looking like it's risen a bit. But remember that with the rocker-bogey system, one wheel rising doesn't mean rover rising.

Posted by: centsworth_II Nov 18 2009, 09:04 PM

I used an incorrect wheelbase dimension in my previous calculations. I have added edits.
The total calculated tilt change of about 0.1 degree remains the same.

The paper I quote in my previous post says, "Wheel baseline is roughly one meter side-to-side..." And in http://www.unmannedspaceflight.com/index.php?s=&showtopic=5456&view=findpost&p=130529 "Wheel width is 160mm - and the distance between the insides of the wheels is 900mm for the front and rear wheels..." That would give 106cm between wheel center lines, not the 145cm I originally used.

Posted by: Astro0 Nov 18 2009, 09:34 PM

So, the less 'scary' version based on everyone's calculations above (ie: 0.1degree after .25secs)
Almost imperceptible!


Posted by: centsworth_II Nov 18 2009, 10:09 PM

QUOTE (Astro0 @ Nov 18 2009, 04:34 PM) *
So, the less 'scary' version...

Let's hope that's closer to reality. smile.gif

Posted by: Astro0 Nov 18 2009, 10:25 PM

Sol2088 Navcams taken at 13:37.52 and 13:41.40 local time.


Posted by: fredk Nov 18 2009, 10:51 PM

According to http://twitter.com/marssciencegrad/status/5830712110 it looks like there'll be another drive attempt on sol 2090. If it's around noon or 1pm local Spirit time, that'd be November 19th, 4 - 5 am California time, or 12:00 - 13:00 UT. wheel.gif

Posted by: briv1016 Nov 19 2009, 12:41 AM

Second drive should be similar to the first:

http://marsrovers.jpl.nasa.gov/spotlight/20091118a.html

Posted by: djellison Nov 19 2009, 08:10 AM

The second commanded drive is similar to the first commanded drive.

I think we're probably hoping the actual drives are a bit different smile.gif

Posted by: Tesheiner Nov 19 2009, 06:40 PM

Some data flowing in the tracking web.
Dunno how many steps were executed but the net advance seems to be about 1cm.

Posted by: centsworth_II Nov 19 2009, 07:09 PM

QUOTE (Tesheiner @ Nov 19 2009, 01:40 PM) *
...net advance seems to be about 1cm.
That would be fantastic, considering the tilt restraint that must still be pretty tight.

Posted by: climber Nov 19 2009, 07:25 PM

I do have basic questions here that apparently have not been addressed since we all thought we'll drive backward.
Assuming the crust will not broke more, what is the distance for Left front to reach firm terrain? (Same question for Middle an Back weels from both sides)
I mean, once LF will be in firm terrain the traction could improve a bit and so on when more weels will meet it. I'll also say the Middle Right will be the first to get to firm terrain, correct?
How this compare to purgatory?

Posted by: centsworth_II Nov 19 2009, 07:41 PM

QUOTE (climber @ Nov 19 2009, 02:25 PM) *
...what is the distance for Left front to reach firm terrain?
My guess is about one meter before the LF gets out of churned up soil, if they stay on the tracks. As said by many, there are so many differences that a comparison with purgatory would not mean much.

Posted by: JohnVV Nov 19 2009, 08:16 PM

this is reminding me of something a few years back ( well many )
seeing a Corvette balancing on a OVERLY tall speed bump . it bottomed out on it and had the back wheels up in the air about 1.5 in.

Posted by: Burmese Nov 19 2009, 08:40 PM

Since the poor RF wheel is stuck with undesirable bulldozing up front on the solid terrain, does anyone have any idea what is its' lowest-drag profile? It's currently set square with the other wheels but one wonders if a bit of toe-in or toe-out might slightly reduce drag/pile-up and maybe induce a bit clockwise twist to the whole rover movement. The equation gets even more interesting (complicated) when the rover does a 'crabbing' move...

Posted by: fredk Nov 19 2009, 08:46 PM

We've got movement! Sol 2088 to 2090:
http://qt.exploratorium.edu/mars/spirit/forward_hazcam/2009-11-17/2F311735004EFFB205P1214R0M1.JPG
http://qt.exploratorium.edu/mars/spirit/forward_hazcam/2009-11-19/2F311913928EFFB206P1214R0M1.JPG

Posted by: Tesheiner Nov 19 2009, 08:52 PM

Not only movement but I think the LF wheel has moved up a little bit so it's not digging in the soil.

Posted by: centsworth_II Nov 19 2009, 09:00 PM

The RF wheel looks to have moved ahead in relation to the small rock next to it by as much as a cm*. I can't wait for the flickers!

*edit: Compared to 11/17/09 hazcam.

Posted by: elakdawalla Nov 19 2009, 09:27 PM

To play devil's advocate, one reason why the horizon would drop in the front camera view would be if the rover were sinking in back. I'm having a hard time judging what's going on in the rear hazcam views -- anyone care to interpret?

Attached is fhaz animation, I'm working on rhaz.

 

Posted by: Astro0 Nov 19 2009, 09:37 PM

Rear Haz



Doesn't look too bad.
I think that there's a view from the MI that might show something. Will upload in a second.

Posted by: climber Nov 19 2009, 09:40 PM

I can see quite some differences in LF smile.gif .
There are little agregates (?) on the rigth of the soil in front of it that end up near the edge of the soil in front of it while they were further (sorry, I miss words to be precise enough in my description); And, I agree Eduardo, I can see it (LF) moving up quite a bit. It seams that some soil in front of LF is now under it, i.e. the weel went up a bit.

Posted by: Astro0 Nov 19 2009, 09:42 PM

MIs sol2088-2090 view to LR wheel.



It suggest to me that the right-middle wheel maybe lifting.
There are some pancams of both middle wheels that need to be compared.

Posted by: centsworth_II Nov 19 2009, 09:42 PM

QUOTE (elakdawalla @ Nov 19 2009, 04:27 PM) *
To play devil's advocate, one reason why the horizon would drop...
Regardless of the horizon, in the last drive the front left cleared a lot of sand and the front right pushed forward noticeably in relation to that small rock next to its front tread. smile.gif

Posted by: Astro0 Nov 19 2009, 09:43 PM

Centred MI view and Navcam view.


Posted by: centsworth_II Nov 19 2009, 09:46 PM

Do I see the pointed rock fading into the distance? laugh.gif



Posted by: tacitus Nov 19 2009, 10:06 PM

This looked extremely promising, though I guess we'll have to wait upon the official word on how they thought it went.

Posted by: Steve Holtam Nov 19 2009, 10:17 PM

My first contribution:



Movement for sure!

Posted by: bgarlick Nov 19 2009, 10:38 PM

QUOTE (Steve Holtam @ Nov 19 2009, 02:17 PM) *
Movement for sure!


Looks encouraging!

Seeing the stuck right wheel slide made me wonder if the tread on the bottom of the wheel has worn off by now? Has this been discussed? According to this quote I found on a NASA site "At 26 centimeters in diameter (a little over ten inches), these aluminum wheels are twice the size of those on Sojourner" it appears the wheels are aluminum which is soft. Spirit has been dragging the wheel for a while and sometimes over hard material such as on home plate. Is it possible that the tread on the bottom is now completely worn smooth? Did NASA use a worn tread right front wheel when doing sandbox tests? (I suppose if the treads are caked with material anyway it might not make much difference, but for future mobility over hard material it could be adventageous if the tread is now gone) (at the very least it is good the wheel froze without the criss-cross-lander-attachment-point-tread pointing down!)

Posted by: Tesheiner Nov 19 2009, 10:40 PM

QUOTE (centsworth_II @ Nov 19 2009, 10:46 PM) *
Do I see the pointed rock fading into the distance? laugh.gif

Had the same thought.

Posted by: fredk Nov 19 2009, 10:48 PM

QUOTE (elakdawalla @ Nov 19 2009, 10:27 PM) *
one reason why the horizon would drop in the front camera view would be if the rover were sinking in back.

There appears to be a 1 pixel drop on the left side of the horizon in the front hazcam views between 2088 and 2090. That corresponds to a pitch up at the front by about 0.1 degree. There's a corresponding lift of the right side of the horizon in the rear hazcam views. Considering that that may have more to do with rocker/bogey than wheels, that sounds like nothing to write home about to me.

The movement of the horizon in the front hazcams appears to be mainly a shift to the left. That means the rover is yawing clockwise as viewed from above, which is what you'd expect with the dead RF wheel. Again though, the yaw angle is very small.

MIs are consistent with us moving forward. It's really good to see LF eating into the soil in front of it, and the RF make progress too.

Tweaked rear hazcam comparison, 2088 to 2090:

Posted by: centsworth_II Nov 20 2009, 01:15 AM

QUOTE (climber @ Nov 19 2009, 04:40 PM) *
...some soil in front of LF is now under it...
QUOTE (fredk @ Nov 19 2009, 05:48 PM) *
It's really good to see LF eating into the soil in front of it...

Right! I tried to match features on the pile in front of the LF and a lot of the face of the mini cliff in front of the LF seems to have fallen away, but there is no pile of fallen material visible. In fact, a pile of material (orange arrows) that was present before the drive is also missing.

Before drive.............. After drive

Posted by: fredk Nov 20 2009, 01:57 AM

From the http://marsrovers.jpl.nasa.gov/spotlight/20091119a.html

QUOTE
After spinning the wheels for the equivalent of 2.5 meters (8.2 feet) in the forward direction, the center of the rover moved approximately 12 millimeters (0.5 inch) forward, 7 millimeters (0.3 inch) to the left and about 4 millimeters (0.2 inch) down. The rover tilt changed by about 0.1 degree.

And this was really interesting - she actually made too much progress in her first step, so the second was cancelled!
QUOTE
The drive plan had imposed a limit of 1 centimeter (0.4 inch) motion in any direction. The second step of the drive was not performed, because Spirit calculated it had exceeded that limit.

Posted by: PDP8E Nov 20 2009, 03:01 AM

Here is a little animation of the underbelly of Spirit (sols 2088 -2090)
I dusted off the program that s t r e t c h e s the heck out of the histogram of the images (no respect for gamma)



Cheers

(Stu -- sorry to hear about the flooding -- your family and friends are in our thoughts)


Posted by: Tman Nov 20 2009, 07:30 AM

Animation middle right and left (Pancam L257):

new http://www.unmannedspaceflight.com/index.php?s=&showtopic=6291&view=findpost&p=150717

Posted by: centsworth_II Nov 20 2009, 07:45 AM

QUOTE (Tman @ Nov 20 2009, 02:30 AM) *
Animation middle right and left...
Wow! That RM cleaned up nice! The LM seems to have dug in, but I like those clean cleats on the RM -- ready to grab hold and push the RF along.

Posted by: climber Nov 20 2009, 08:30 AM

QUOTE (fredk @ Nov 20 2009, 02:57 AM) *
From the http://marsrovers.jpl.nasa.gov/spotlight/20091119a.html

And this was really interesting - she actually made too much progress in her first step, so the second was cancelled!

Another 600m and we're out blink.gif

Posted by: mcgyver Nov 20 2009, 04:03 PM

as the most annoying thing of sand is it keeps falling on you while you dig... would it be possibile for the IDD to remove the sand over the wheel, to prevent it from burying the wheel itself?

EMBEDDED IMAGE REMOVED - please either attach images or post links to them offsite -- embedding makes life difficult for people with slow connections or small screens.

Posted by: MahFL Nov 20 2009, 04:59 PM

The IDD is not a shovel........so NO.

Posted by: mcgyver Nov 20 2009, 05:44 PM

QUOTE (MahFL @ Nov 20 2009, 05:59 PM) *
The IDD is not a shovel........so NO.

never mind what it is designed for, think of what it CAN do! "http://en.wikipedia.org/wiki/Lateral_thinking" smile.gif , or we'll never get out of there!

Posted by: Steve Holtam Nov 20 2009, 06:04 PM

There is no way they are going to be shoveling with the IDD. MahFL was being polite by just saying NO.

Posted by: mcgyver Nov 20 2009, 06:17 PM

QUOTE (Steve Holtam @ Nov 20 2009, 07:04 PM) *
There is no way they are going to be shoveling with the IDD. MahFL was being polite by just saying NO.

are there any other reasons than "don't want"? I can see in pictures that IDD can reach the sand near the wheels, and maybe it even already touched it (not sure about little circluar print on the sand hill)

FOR THE SECOND TIME IN LESS THAN A DAY: DO NOT POST BIG IMAGES INLINE! LINKS OR ATTACHMENTS PLEASE! THE IMAGE WAS COMPLETELY UNNECESSARY TO YOUR POST ANYWAY. --ADMIN

Posted by: centsworth_II Nov 20 2009, 07:25 PM

QUOTE (mcgyver @ Nov 20 2009, 11:03 AM) *
... would it be possible for the IDD to remove the sand over the wheel
I'm sure the team has thought of this, as it is an obvious thought. Whether the consensus is "not in your wildest dreams" or " Plan D", I don't know. But so far plan A seems to be working fine.

My own feeling is that if the IDD could reach the area, it would likely only be able to touch the top of the pile and would end up pushing as much of it against the wheel as away. The wheel itself seems a much better tool for moving soil, as evidenced in this last drive.

Posted by: algorimancer Nov 20 2009, 09:10 PM

One thing I'm led to wonder is whether the surprising (?) progress is due to packing of the underlying soil due to sitting in one place for so long. This might motivate a strategy if the current plans otherwise go awry. Hoping I'm wrong.

Posted by: brianc Nov 20 2009, 10:02 PM

We just need to all sit back, calm down and have some patience here, these chaps know what they're doing

After 12 driving sols we will have backed out onto the firm ground - you mark my words tongue.gif

Posted by: fredk Nov 20 2009, 11:14 PM

Oooh, that sounds like a call for a Spirit Extraction Pool. Some of our members would be absolutely thrilled about that! tongue.gif wink.gif laugh.gif


NO MORE POOLS PER DOUG - ADMIN

Posted by: fredk Nov 21 2009, 04:25 AM

Third drive attempt soon, according to the http://marsrovers.jpl.nasa.gov/spotlight/20091120a.html

QUOTE
This time, however, the right rear wheel will be commanded at a slightly slower speed to allow the right middle wheel to gain more traction. This is to mitigate the potential for a wheelie by the right middle wheel. There will also be tighter limits on the rover's change in direction (yaw) and the angles of the suspension system.

Posted by: Astro0 Nov 21 2009, 07:17 AM

A different view of the Sol2088-2090 move.


Posted by: Keatah Nov 21 2009, 07:47 AM

QUOTE (Astro0 @ Nov 21 2009, 07:17 AM) *
A different view of the Sol2088-2090 move.


Yeh! For some strange reason I saved the gif to my 'marspics' folder and titled it, "Getting Underway.gif" - sort of reminded me of a ship pulling away from port.

Posted by: Tesheiner Nov 21 2009, 08:42 AM

QUOTE (fredk @ Nov 21 2009, 05:25 AM) *
Third drive attempt soon, according to the http://marsrovers.jpl.nasa.gov/spotlight/20091120a.html

Planned for sol 2092 i.e. today.

Posted by: jamescanvin Nov 21 2009, 08:15 PM

Some data on the tracking site now. Looks like about 5mm progress forward, although worryingly, another 4mm 'down'.

Posted by: Tesheiner Nov 21 2009, 08:50 PM

And this time it looks like the two steps were executed.

Posted by: Oersted Nov 21 2009, 09:19 PM

I'm wondering if "down" might just mean that the mid part of the rover is down a bit, but the rear is moving up.

Posted by: fredk Nov 21 2009, 10:19 PM

Less progress on 2092 than on 2090:
http://marsrovers.jpl.nasa.gov/gallery/all/2/f/2088/2F311735004EFFB205P1214R0M1.JPG
http://marsrovers.jpl.nasa.gov/gallery/all/2/f/2090/2F311913928EFFB206P1214R0M1.JPG
http://qt.exploratorium.edu/mars/spirit/forward_hazcam/2009-11-21/2F312092660EFFB208P1214R0M1.JPG

Here's a tweaked version of the rear wheels:



It looks like there was a bit of a roll to the left and further yaw like in the last drive. Impossible to say what all this means yet.

Posted by: HughFromAlice Nov 21 2009, 10:21 PM

Movie of 2 forward left hazcam pics taken on Sol 2092 - Earth Time Sun Nov22.
2F312091613EFFB207P1235L0M1.JPG
2F312092660EFFB208P1214L0M1.JPG

First pic with IDD (arm) down and second pic about 18 mins later. Looks like that revolving left wheel is pushing up a bit of 'sand'. Rover slewing a bit to the right and probably not sinking in relation to that wheel. And, dare I say it, possibly a bit of movement towards safe ground! That critical right wheel - looks like no perceptible movement in relation to ground.



Just seen your post Fred - yaw right at front = left at rear?!! It's a bit early on Sun morning here!!!

Posted by: Astro0 Nov 21 2009, 10:48 PM

Front, Rear and Nav sequences from sol2088 to sol2092.
Front and rear sol2092 show both steps.



Posted by: Tman Nov 21 2009, 10:57 PM

I do not like the repeated down movement of the right RW.

Full res. http://i48.tinypic.com/a9r8kp.gif of the progress from the Forward Hazcam (by Mirko from the German forum)

Posted by: Burmese Nov 22 2009, 12:27 AM

The LF wheel is still steadily shoveling soil and that should start to pay dividends. Wonder when they will try some crabbing?

Posted by: djellison Nov 22 2009, 02:49 PM

Some rough and ready renderings of Scamander crater based on the OSU elevation map posted with the press conf a week or so ago. The exaggerated elevation is 5x exaggerated.


 

Posted by: PDP8E Nov 22 2009, 05:20 PM

doug
your renderings are very cool

Posted by: Oersted Nov 22 2009, 09:30 PM

I agree, excellent renderings.

Posted by: Hungry4info Nov 22 2009, 10:18 PM

Looks like we're again imaging underneath the rover.
http://qt.exploratorium.edu/mars/spirit/forward_hazcam/2009-11-22/2F312092535ESFB208P1162L0M1.JPG
http://qt.exploratorium.edu/mars/spirit/forward_hazcam/2009-11-22/2F312092935ESFB208P1162L0M1.JPG

Looks different now (i.e. farther in the distance). Touching?
http://qt.exploratorium.edu/mars/spirit/micro_imager/2009-11-22/2M312092879EFFB208P2926M2M1.JPG

Posted by: PDP8E Nov 23 2009, 12:49 AM

Here is an animation of the underbelly of Spirit over the last 3 imaging sessions (sols 2088, 2090, 2092)
I have pushed tortured the histograms and did some adaptive processing



Cheers

Posted by: Tman Nov 23 2009, 05:42 AM

Animations middle right and left (Pancam L257):

new: http://www.unmannedspaceflight.com/index.php?showtopic=6291&view=findpost&p=150822

Posted by: Steve Holtam Nov 23 2009, 06:28 PM

Three steps -

ADMIN - PLEASE DO NOT POST LARGE IMAGES DIRECTLY INLINE. UPLOAD AS AN ATTACHMENT FOR PEOPLE WITH SLOW CONNECTIONS ETC. SEE BELOW

 

Posted by: jamescanvin Nov 23 2009, 07:18 PM

http://www.jpl.nasa.gov/freespirit/

Last drive was aborted after 4m worth of wheel spinning due to a RR stall.

Sequencing diagnostics today (for nextersol, 2095)) including a possible steering test, a small backward rotation of just the right-rear wheel and a short (~1m) forward drive of all wheels.

Posted by: Hungry4info Nov 23 2009, 08:41 PM

QUOTE (jamescanvin @ Nov 23 2009, 01:18 PM) *
all wheels.

How is this defined for Spirit?

Posted by: fredk Nov 23 2009, 09:07 PM

The story James linked to only mentions a "forward commanded motion of the rover", not a drive of all the wheels. Obviously the RF won't take part in the drive, and the only question is whether the RR will. But without the RR, three left wheels vs one right wheel means she'd yaw over to the right pretty severely I'd think.

Posted by: climber Nov 23 2009, 09:38 PM

QUOTE (fredk @ Nov 23 2009, 10:07 PM) *
... But without the RR, three left wheels vs one right wheel means she'd yaw over to the right pretty severely I'd think.

I don't see any reason for that since the stall ended the drive. This is confirmed by the motion in all axis been a matter of mm. So, "severely" is may be over stated. May have been a "tendency" instead?

Posted by: fredk Nov 23 2009, 10:41 PM

Are you thinking that the RR may not have been turning much during the entire last drive? If that's true, then you're right. Three left and one right wheel driving didn't yaw her over much - it didn't make very much progress period.

But we don't know how the RR behaved during the entire last drive. Maybe it slowed down only at the end, just before the drive was aborted. If that's the case, then 3L + 1R driving might still yaw us a lot more than we've seen yet. Still, traction is worse on the left side, so it's not clear what might happen.

Posted by: paxdan Nov 23 2009, 10:44 PM

QUOTE (djellison @ Nov 22 2009, 02:49 PM) *
Some rough and ready renderings of Scamander crater based on the OSU elevation map posted with the press conf a week or so ago. The exaggerated elevation is 5x exaggerated.

But not the tilt of the rover?

Posted by: djellison Nov 23 2009, 11:00 PM

Problem is they removed a local tilt to produce the DEM- and I don't know how much - so it was guess work on how to place the rover in terms of tilt etc.

Posted by: PDP8E Nov 24 2009, 02:51 AM

Here is the underbelly animation showing more of the left side (looking under and to the back of the vehicle..2088,90,92)
A rocker or a boogy is really moving, maybe someone can illuminate what is (mechanically) happening with that kind of motion?
Also notice in this animation as well as the other a few posts back, that the ground appears to heave up on the 2092 image.
Well, the ground isn't heaving up, the camera platform (Spirit) is digging in and so it is lower (yikes!)



Cheers

(there is one more animation set showing more of the right side (the Scamander side) that I will be getting to ...)

Posted by: alan Nov 24 2009, 03:28 AM

Question: has anyone seen the origin of Scamander discussed?

Is it assumed to be an old impact crater that was filled with the loose bright material or could the hollow have been formed by the same process that produced the material.

Posted by: PDP8E Nov 24 2009, 04:34 AM

Here is the last animation based on Sols 2088,90,92 that show the rightmost section of the undercarriage of Spirit
One thing I would like to point out is the repeatability of the camera pointing; the arm deploys the MI to the exact same places over many sols - I have not made any attempt to align the images - awesome engineering!



Cheers

Posted by: Tesheiner Nov 24 2009, 08:52 PM

The images from today's diagnosis / drive are available: http://qt.exploratorium.edu/mars/spirit/forward_hazcam/2009-11-24/
And looking at the data available at the tracking web, the net movement was 2.5mm N and 1.3mm W.

Before: http://qt.exploratorium.edu/mars/spirit/forward_hazcam/2009-11-21/2F312092660EFFB208P1214L0M1.JPG
After: http://qt.exploratorium.edu/mars/spirit/forward_hazcam/2009-11-24/2F312356114EFFB214P1214L0M1.JPG

Posted by: fredk Nov 24 2009, 08:56 PM

There is some movement in the soil behind the RR wheel after tosol's RR wheel diagnostic drive:


That sounds like a positive sign (tea leave), but we'll have to hear what they say in the next official release.

Posted by: Hercules Nov 25 2009, 01:14 PM

Full quote of previous post removed - Mod

These images appear to show the ground moving away, which is a very good sign. The three attempts at movement so far have been very promising but I became concerned by the front Hazcam views from Saturday that appear to show that the locked right front wheel has lodged against a small stone and did not appear to move when there was a clear movement from the left front wheel. I wondered what would happen if Spirit rotates around the locked front wheel. Would this cause the rover to slide further into Scamander crater?

Posted by: djellison Nov 25 2009, 01:53 PM

I see clear motion on the FR during the last drive. Small, but so was the motion from the FL. I don't think small pebbles etc are going to significantly increase the drag caused by that wheel.

Posted by: Tman Nov 25 2009, 05:16 PM

Animations of middle right and left wheel (till sol 2095):


Posted by: tacitus Nov 25 2009, 08:11 PM

There was no stall of the suspect wheel during the diagnostic drive, so it's full speed ahead (relatively speaking!) for the next 5m drive over the Thanksgiving weekend.

Posted by: fredk Nov 25 2009, 08:44 PM

http://marsrovers.jpl.nasa.gov/spotlight/20091125a.html

Posted by: JayB Nov 25 2009, 09:11 PM

@marsroverdriver (Should be careful here: #FreeSpirit progress on Mars -- actual motion vs. commanded motion -- is right on predicts. Almost scary.)

good (cautious) news from twitter

Posted by: nprev Nov 25 2009, 09:14 PM

Huh. Swear I just heard a sound like hundreds of thousands of fingers crossing...

wheel.gif wheel.gif wheel.gif

Posted by: Steve Holtam Nov 25 2009, 09:43 PM

Four Steps.



Posted by: PDP8E Nov 26 2009, 03:43 AM

Here is a Spirit undercarriage animation that spans sols 2081, 88, 90, 92, and 2095
It shows the center view... the JPL engineers have been taking, what I call, a left, center, and right view of the underbelly after drives. Incredibly, the IDD arm places the MI at the exact same place (+/- a pixel or two) over 2 weeks.
I have tortured the histograms to get the lighting bearable.
If anyone wants to try a Lucy-Richardson or any other focusing trick, I can provide the the individual processed frames via flickr.



Cheers






Posted by: CosmicRocker Nov 26 2009, 05:18 AM

QUOTE
... @marsroverdriver ... -- is right on predicts.

...is right on predicts? ...is right on predicts???

Might he mean, "...is right on predictions?" Where is our language going these days? ohmy.gif

Posted by: stevesliva Nov 26 2009, 05:49 AM

Just making the verb predict more like the verb target.

Posted by: climber Nov 26 2009, 08:00 AM

QUOTE (CosmicRocker @ Nov 26 2009, 06:18 AM) *
...is right on predicts? ...is right on predicts???

Might he mean, "...is right on predictions?" Where is our language going these days? ohmy.gif

Scott's a Martian mate...

Posted by: djellison Nov 26 2009, 08:13 AM

I've always heard 'predicts' used rather than 'predictions' in space ops.

Posted by: serpens Nov 26 2009, 08:41 AM

Full in-line quoting removed. That certainly ISN'T right - ADMIN

And that somehow makes it right?

Posted by: centsworth_II Nov 26 2009, 08:43 AM

I'd rather it be spaceflight ops -- I mean operations -- jargon than twitterese! laugh.gif

Posted by: centsworth_II Nov 26 2009, 08:46 AM

QUOTE (serpens @ Nov 26 2009, 03:41 AM) *
And that somehow makes it right?
Lots of professional jargon has not made it into the dictionary. You want behind the scenes info (I mean information) but not behind the scenes lingo (I mean language)?

Posted by: djellison Nov 26 2009, 09:03 AM

QUOTE (serpens @ Nov 26 2009, 08:41 AM) *
And that somehow makes it right?


Yes.

If you want to have a pathetic argument about language and the lexicon of space-ops, find another forum.

While we're playing pedant, you might want to stop breaching forum etiquette via full in-line quoting.

Posted by: Steintor Nov 26 2009, 09:12 AM

wheel.gif
Does any of you have insight into the next moves of the rover extraction team at JPL. What do they expect from the next drive.. and the whatifs that must have been planned in detail ?

Not knowing what action plans is made, is no fun at all. sad.gif

Posted by: HughFromAlice Nov 26 2009, 09:19 AM

QUOTE (fredk @ Nov 26 2009, 06:14 AM) *
http://marsrovers.jpl.nasa.gov/spotlight/20091125a.html


From NASA MER Site 25 Nov - "The cumulative results from Sols 2088 to 2095 (Nov. 17 to 24) are 8.1 meters (27 feet) of commanded motion, 15.7 millimeters (0.6 inch) of forward progress, 9.9 millimeters (0.4 inch) of movement to the left, and 4.8 millimeters (0.2 inch) of sinkage"

This is pretty much as predicted......

My qs -
1- How many mms until sinkage starts to become critical?
2 -At what rate can we afford to sink in proportion to foward movement?

Anyone got any comments or ideas?

Posted by: djellison Nov 26 2009, 10:22 AM

QUOTE (Steintor @ Nov 26 2009, 09:12 AM) *
What do they expect from the next drive..


More of the same - moderate driven commands (5 metres) with very very small progress ( 5-10 mm )

Essentially - we're looking at a 99.5+% slip rate - but it's still progress.


It looks to me as if the belly-rock is shifting with the rover, so as that shifts we may have more 'headroom' for sinkage whilst making progress.

Posted by: Reed Nov 26 2009, 10:26 AM

QUOTE (HughFromAlice @ Nov 26 2009, 01:19 AM) *
2 -At what rate can we afford to sink in proportion to foward movement?

Not exactly what you are after, but Scott Maxwell http://twitter.com/marsroverdriver/status/5960641128
QUOTE
~50cm until we're clear of Belly Rock on forward path. A long way to go, yet

How critical sinking might be depends on the nature of Belly Rock.

Posted by: climber Nov 26 2009, 10:50 AM

So, Scott says we're ~50cm from clearing Belly Rock. How many more cm we'll we need to see Belly Rock appears in Rear Hazcam?

Posted by: djellison Nov 26 2009, 11:21 AM

50cm. biggrin.gif The bottom of a Hazcam image is the ground directly below it So we will see the rock appear at the bottom of Hazcams as we get clear of it. Hazcam's FOV is 120 degrees and the pointing is 30 degrees below the horizon - so you get 90 degrees below, and 30 degrees above.

Posted by: brellis Nov 26 2009, 01:45 PM

Does Spirit sink at all during the days off?

I'm just glad I'm not driving her -- I'd be spinning those wheels in a mad panic, hehe.

Posted by: Steintor Nov 26 2009, 03:33 PM

QUOTE (Reed @ Nov 26 2009, 11:26 AM) *
How critical sinking might be depends on the nature of Belly Rock.


I think the sinking rate is more critical than what is discussed, focusing on Belly Rock. The NASA team must surely have a sink/progress ratio maximum that must lead to an alternative strategy. My experience from driving in snow (may not apply at all, but...) is that traction is always better in the places where your wheels havent been. The pictures shows that the piles of sand ahead of the wheels most likely is less compact than the untouched areas (volume). So one can wonder WHEN WILL THEY TURN THE WEELS LEFT?? wheel.gif

Please post your favorite alterative strategies, given the current results.






Posted by: elakdawalla Nov 26 2009, 03:37 PM

One tidbit I remember from the press briefing was John Callas saying that they now treat sinkage as a "consumable" (much like power or flash memory), so it's something they're monitoring very closely. He said something about how it would be "game over" if they sank so much that the belly pan was sitting flat on the ground. Awful image!

Posted by: fredk Nov 26 2009, 03:48 PM

Since we've sunk about 5 mm in these drives, that does suggest Belly Rock is being pushed down too, which would be very good news. And if I squint at PDP's excellent MI animations, I can just imagine that I can see it getting pushed down. But it's still not entirely clear, since we don't know how far along Spirit's belly the rock is. One end of Spirit might be pivoting down and the other held up by the rock.

I have to say that the post by Maxwell that we need 50 cm to clear Belly Rock baffled me. The entire underbelly is only about 60 cm from front to back. So if he meant that we need 50 cm of movement to clear the belly, then the rock had to be around 10 cm from the front initially. But it looked like it was much farther back in the MI's. Maybe he meant we need 50 cm to clear the rear wheels. That would put the rock at something like 40 cm from the front of the belly, and behind the centre of mass, which would make much more sense.

Posted by: fredk Nov 26 2009, 03:56 PM

QUOTE (Steintor @ Nov 26 2009, 04:33 PM) *
WHEN WILL THEY TURN THE WEELS LEFT??

Unfortunately left gets us deeper into Scamander crater and presumably more of the light fluffy stuff. Right now we have better traction on the right wheels (outside the crater) which we don't want to lose...

Posted by: centsworth_II Nov 26 2009, 05:32 PM

QUOTE (fredk @ Nov 26 2009, 10:48 AM) *
...Maybe he meant we need 50 cm to clear the rear wheels. That would put the rock at something like 40 cm from the front of the belly...
Or about 20cm from clearing the belly? Also, the rock extends farther back than its contact point with Spirit. We should begin to see it with the rear hazcam even before it disengages from the belly. Maybe just five or ten more cm?

Posted by: centsworth_II Nov 26 2009, 05:42 PM

QUOTE (Steintor @ Nov 26 2009, 04:12 AM) *
...What do they expect from the next drive...
I see this drive as a control, or baseline drive.

The last couple drives have involved fine tuned maneuvers, with individual wheel adjustments. The next drive is straight ahead with all wheels the same (except the RF of course). This eliminates individual wheel adjustment variables so any rover movement will be only the result of its interaction with the terrain. I expect information from this drive will be used to determine what wheel adjustments will be needed on future drives.

Posted by: imipak Nov 26 2009, 07:30 PM

I'm a glass-half-empty sort of chap...

QUOTE (JayB @ Nov 25 2009, 09:11 PM) *
@marsroverdriver [..] #actual motion vs. commanded motion -- is right on predicts. Almost scary.


Does anyone know if those are /per-drive/ predictions? I took the meaning "...the predictions from the sandbox studies, which suggest success is by no means certain, and this is scary because it looks like Spirit's permanently stuck".

Clearly it's all about the sink rate, for now at least.. A ratio of forward to downward progress of 3:2 doesn't sound very hopeful. Perhaps the left-hand wheels will eventually dig down to the rock of the hidden crater rim, and gain traction...

On the bright side, with a few mm progress per drive, the final (hopefully very long) animation from the front hazcams will look nice and smooth :>

Posted by: fredk Nov 26 2009, 07:47 PM

QUOTE (centsworth_II @ Nov 26 2009, 06:32 PM) *
We should begin to see it with the rear hazcam even before it disengages from the belly. Maybe just five or ten more cm?

Actually, we have already seen what's below the rear end of the belly. On sols 1871 and 1886 we were a bit farther north of our current location, so the rear hazcams from those sols show what's currently invisible under the rear belly. In this mosaic I've identified two groups of rocks in each frame, and circled one group in white and the other in black. In the current (2095) view, the black-circled rocks are just visible. From the 1886 frame we can see that we'll see a few smallish rocks first before Belly Rock.



The 1871 view is really interesting. In that frame I've circled two new groups of rocks in grey (the farther of these groups is also visible at the bottom of the 1886 frame). I've identified those grey-circled groups in the sol 1870 navcam anaglyph view, and again circled them in grey:



Also on this navcam view, I've circled my identification of Belly Rock in white. Looking back at the 1871 hazcam view, it looks like the LR wheel was actually sitting on part of Belly Rock! So it looks like we did drive over Belly Rock, and hopefully loosened it up as well.

Posted by: elakdawalla Nov 26 2009, 07:52 PM

Oh, don't overthink the "almost scary" business. Scott's a typical engineer, always expecting the worst and obsessively hunting for the mistakes and errors he KNOWS have to be in there somewhere. If things are going well, that just means he hasn't caught the mistake he must have made! He'll be sure he's wrong until Spirit's out of there safely. And then he'll find something else to worry about.

Posted by: climber Nov 26 2009, 08:10 PM

Reading "Mars & Me", I understand perfectly what you mean. Nice analyse rolleyes.gif

Posted by: Bobby Nov 26 2009, 09:48 PM

Long time since I have posted in the Thread or any other one.
I am still sick with a thyroid issue and being treated now for it.
Hopefully soon I will be better.

Back to the topic at hand. I have heard people discussing using
the arm with all the tools to lift the rover up a little. Has anyone ever
thought about using the grinder tool part that is not working anymore
as a plow to move some of the dirt, sand or what ever it is in front
of that one wheel? If they did that would that be less resistance on
that front wheel making it easier for it to get a grip? I think it's worth a
shot. Is there any small rocks we can shove in front of that wheel also so
it has a solid surface to grab onto???

Just me thinking of other things we can do to help Spirit out

Bobby

Posted by: Reed Nov 26 2009, 10:53 PM

QUOTE (Steintor @ Nov 26 2009, 07:33 AM) *
I think the sinking rate is more critical than what is discussed, focusing on Belly Rock.

What I was trying to get at is if Belly Rock is firmly embedded, that would be the first thing they hit. If it's not, sinking is still a problem, but the acceptable limit must be larger.
QUOTE
Please post your favorite alterative strategies, given the current results.

My favorite strategy is for the people who have spent the last five years driving the rovers, and last several months studying the problem do what they do best. wheel.gif wheel.gif wheel.gif

I take Scott Maxwells "almost scary" to mean "wow this is amazingly close to what we predicted" not anything to do with fear. The http://twitter.com/marsroverdriver/statuses/6061144512 is also relevent
QUOTE
(It's only #FreeSpirit progress *by the calendar* that's slower than I hoped yet faster than I feared. Even by that measure we're doing OK.)


Bobby:
The rover team is full of smart, creative people who know their vehicle extremely well. If there's anything to be done with the arm, they've thought about it. However, they have consistently said the arm is not well suited to this and would only be used as a last resort. This is covered in the FAQ thread http://www.unmannedspaceflight.com/index.php?showtopic=6085
Best wishes on your personal recovery.

Posted by: nprev Nov 26 2009, 11:06 PM

QUOTE (Reed @ Nov 26 2009, 02:53 PM) *
I take Scott Maxwells "almost scary" to mean "wow this is amazingly close to what we predicted" not anything to do with fear.


Yes, precisely, as Emily explained. Just to amplify, phrases like "almost scary" in this context are used in current US slang to mean exactly what you stated, Reed.

US English slang of this type tends to accentuate opposites (often sarcastically), while UK English slang in the same vein tends towards understatement. I'll let everyone know when it all changes in the US again in six months or so... tongue.gif

Posted by: centsworth_II Nov 27 2009, 04:42 AM

Given the many unknowns and an uncannily accurate prediction, I would say that "almost scary" also alludes, sarcastically, to a supernatural component such as clairvoyance.

Posted by: briv1016 Nov 27 2009, 10:37 AM

According to the tracking site the next drive is sol 2099.

Posted by: PDP8E Nov 28 2009, 03:59 AM

Here is an underbelly image from Sol 2061 (before extrication maneuvers)
There is a before and after image
I rotated the 'after' to have a level under-deck.
I don't think belly rock is touching (I wish I could be sure!)
oh well, just waiting for the next drive (Sol 2099)
Your mileage may vary



Cheers

Posted by: briv1016 Nov 29 2009, 02:53 AM

Very little apparent movement from today’s drive. On a related note, how are you guys getting Spirits movement from the tracking site?

Posted by: bgarlick Nov 29 2009, 06:16 AM

QUOTE (briv1016 @ Nov 28 2009, 06:53 PM) *
Very little apparent movement from today’s drive. On a related note, how are you guys getting Spirits movement from the tracking site?


Yes, looking at the forward and rear hazcams it looks like Spirit just pivoted ever so slightly clockwise around the RF wheel which did not slide at all.
Should Spirit continue to try to move forward (which may just cause more pivoting around that wheel), or should she back up a bit and try then pushing forward again to get the RF sliding again? I guess we will just wait and see what they try next...

Posted by: Tesheiner Nov 29 2009, 11:23 AM

Minimal movement, indeed. Besides, only one step was executed not two; my guess is that it was somehow aborted.

On another note, today is sol 2100!

Posted by: marsophile Nov 30 2009, 04:43 PM

QUOTE (bgarlick @ Nov 28 2009, 11:16 PM) *
Should Spirit continue to try to move forward (which may just cause more pivoting around that wheel), ...


If Spirit could pivot all the way around the RF wheel, it would be out of the crater and facing in the opposite direction. At that point it could just drive backward dragging the wheel again. So maybe pivoting is not so bad.

Posted by: Marz Nov 30 2009, 07:42 PM

Wow, this is just a nail-biter to wait for news each day. Let me see if I can summarize the action for those of us who've missed a few days of news due to holidays.

Short term goal: move forward 50 cm to clear Belly Rock.
Long term goal: move forward ~1m to escape Troy?

Update for Sol 2095 (Nov 24th)
Total commanded movement since Sol 2088 (Nov 17): 8.1 m
Total successfully processed movement (wheel spin): 5.6 m

Total forward movement: 15.7 mm
Total sinkage: 4.8 mm

Perhaps it's meaningless to project with just 2 datapoints, but if this ratio of motion is maintained, then to clear Belly Rock Spirit must churn about 178m of wheel spinning and could sink 150mm!

Posted by: paxdan Nov 30 2009, 07:46 PM

It is similar to the 192m of wheel turns it took to move 1m to get out of purgatory

Posted by: djellison Nov 30 2009, 08:04 PM

Some people have very short memories smile.gif

Posted by: Tesheiner Nov 30 2009, 09:09 PM

QUOTE (Marz @ Nov 30 2009, 08:42 PM) *
Short term goal: move forward 50 cm to clear Belly Rock.
Long term goal: move forward ~1m to escape Troy?

I wouldn't call that "short term goal" but "medium term" or even "long term".
The short term goal is, IMO, keep making a steady progress.

Posted by: serpens Dec 1 2009, 12:30 AM

Was there any sinkage reported during the purgatory extraction?

Posted by: PDP8E Dec 1 2009, 03:12 AM

Here is the underbelly MI animation from Sols 2081, 88, 90, 92, 95, 2099 (center MI view)
There is minor movement on 2099 as commented before.



Cheers

Posted by: JayB Dec 1 2009, 02:54 PM

In case you haven't seen, Odyssey's in Safe mode again
http://www.jpl.nasa.gov/news/news.cfm?release=2009-181&icid=%27NewsFeaturesHome%27

Wondered how this would affect extraction Got this reply from Scott on Twitter last night

"Unclear. Possibly no effect: they might be out of safe mode by the next time we can try to #FreeSpirit anyway (Wednesday)."

Posted by: Steve Holtam Dec 1 2009, 06:31 PM

Five steps.

I sure hope that stuck wheel starts to slide.


Posted by: djellison Dec 1 2009, 07:00 PM

The reversion from the last frame to the first shows clearly that it already is. It's not moving as much as the FL - but it IS moving.

Posted by: Phil Stooke Dec 1 2009, 07:32 PM

Also, if the wheels are moving material from in front of them to behind them they are doing something very useful. There might be no motion for ten drives while stuff is moved by the wheels, then suddenly you get a bit of a move, and that sequence is repeated as often as necessary.

Phil

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