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Unmanned Spaceflight.com > Mars & Missions > Past and Future > MER > Spirit
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PhilCo126
Spirit has been stuck for 111 days pancam.gif sad.gif
Did I miss out on the name of the 2nd test rover the JPL team began using?
http://www.jpl.nasa.gov/freespirit/
elakdawalla
Thanks for the numbers, Deimos!

Phil: It's called SSTB Lite.
Stu
Crop of new HiRISE image - taken June 13th - released today ( http://hirise.lpl.arizona.edu/ESP_013499_1650 )... that bright object to left of HP is Spirit, right?

Click to view attachment

Edit: guess it is; Doug already spotted it and posted a pic on Twitter. Looks like a heck of a mess around Spirit!
nprev
Wow! Caught the reflection off her arrays, eh? What a beautiful shot.
elakdawalla
I'd like to do an entry of this...got a nice section that covers Spirit's journey and labeled a few features. Is there anything else I should label on this map before I post it?

--Emily
centsworth_II
Maybe Low Ridge [should] be noted as being "Haven #2"
mhoward
Maybe Tyrone.
Tesheiner
Since almost all of the ridges are labelled, I'm missing "Mitchelltree Ridge".
briv1016
The MER team has been testing the extraction methods under the assumption that with clean solar arrays Spirit could theoretically weather the Mars winter in the current location if she had to. The latest Planetary Society Update however brings up an interesting point:

QUOTE
“The question now is how much dust will be left on the panel and what the transmission factor will be and what our date will be for parking for winter,” said Arvidson. “We just have to wait and see,” added Laubach.


Elsewhere on the page it mentions that the dust factor is down to 0.658.
fredk
Thanks for pointing out that material in the latest Planetary Society update. I didn't recall that material (or what Tesheiner mentioned about Oppy) when I read the update and posted a few days back. It turns out when I first read it the last two sections (about Spirit and Oppy separately) were not posted yet. There's a lot of info in those sections, especially about the extraction, in case anyone out there missed them too. Here's an example:
QUOTE
“When we drove here around Sol 1871, the vehicle yawed a little bit relative to the preferred drive and we ended up on this slope,” recounted Arvidson. “Based on everything we've done, Spirit wound up in this mess because of that 12-degree roll or yaw to the west,” he said. “We just got into the wrong place at the wrong approach, because of this drift in yaw during the drive.”
Tesheiner
I'll have to read the report again too. I saw it was short but thought it was due to vacations or something similar.
mhoward
QUOTE (Tesheiner @ Sep 4 2009, 03:36 PM) *
I'll have to read the report again too. I saw it was short but thought it was due to vacations or something similar.


I thought it was just me. Glad you pointed that out.
briv1016
Weekly update is now out. As of Sol 2013 tau is down to 0.890 and the dust factor is up to 0.720. As of sol 2014 power is up to 564 watt-hours.
briv1016
Are the "Scamander Plains" images a new 360 panorama in all 13 filters or are they something else? If they are, I think it's a sign that the science people plan on being here for a while. unsure.gif
jamescanvin
I would imagine that it will be an 'as big as time allows' rather than formaly a 360. I'm sure the pancam folks are hoping that it won't be completed. wink.gif Just passing the time...
fredk
Doing some catch-up here. This is an animation of the "penetrometer experiment" done on sol 2006 to test the properties of the soil. It's interesting to see how the surface deforms even well outside the RAT mark:
Click to view attachment
nprev
Nice, Fred!

Seems pretty cohesive, but not as much as, say, flour, which is unfortunate. This stuff looks like it's right in the "unsweet spot": not fine-grained enough to be highly compressible, but fine enough to defeat easy traction.
Juramike
Looks (and seems to behave) like sugar sand.
fredk
Following up on the dust storm, reading the shadows again it looks like the rate of improvement has slowed or even reversed a bit. Compare this sol 2017 image:
http://marsrovers.jpl.nasa.gov/gallery/all...E5P2111L2M1.JPG
with this 2020 image:
http://marsrovers.jpl.nasa.gov/gallery/all...E5P2111L2M1.JPG
The lighting illumination angle is very similar between these images, but the shadow appears to be a bit brighter on sol 2020.

Still, it's far better than the worst of the storm. In a couple of days we should get some new numbers...
PhilCo126
I wonder if the JPL/FreeSpirit team used any of the suggestions made by UMSF forum-members to test extraction techniques huh.gif
Astro0
Given that some of the fourm members ARE rover drivers...then I'd say yes.
Did they use anyone else's suggestions....hmmm, you generally ignore the 'backseat drivers' don't you?! laugh.gif
Oersted
come on NASA, give the tax payers some entertainment, enough of the suspense! Floor it! smile.gif
fredk
Power update from the latest update:
QUOTE
As of Sol 2021 (Sept. 3, 2009), Spirit's solar-array energy production is 418 watt-hours, with an increased atmospheric opacity (tau) of 1.65 and a dust factor of 0.669.
Bobby
Even though I rarely post in this Forum. I wanted to tell all you guys and gals what a wonderful job you are doing. I learn something new every time I read your posts. I think it's amazing what these rovers have done and I enjoy our Little buddies up there. I did forget to post the new PS Rover report this month but will try hard the end of this month for you all. I hope the Journeys of both Spirit and Oppy keep going on and on. Just to let you guys know. I've been sick and battling a real bad Thyroid Disease recently. I should be better in a few months. By then I hope Spirit is Free and Oppy is another 1 KM away from Block Island.

Now Lets Get Spirit Free so we can all biggrin.gif

Bobby The Mars Rover Fan & UMSF Fan
ArMaP
QUOTE (fredk @ Sep 8 2009, 03:40 PM) *
It's interesting to see how the surface deforms even well outside the RAT mark

It's really interesting the way the dust moves, it's as if it was "easier" for the dust to move up than to push the dust around it to the sides, acting much like a fluid inside a container.

Does anyone know if the winter can change the ground conditions, making it easier or more difficult to get Spirit out of there?
ustrax
Get well soon Bobby, the members of the UMSF crew expect you to leave the medical bay and join us in the bow of the vessel.
Ultreya!
fredk
QUOTE (ArMaP @ Sep 13 2009, 06:35 PM) *
Does anyone know if the winter can change the ground conditions, making it easier or more difficult to get Spirit out of there?

Check the extraction faqs.
briv1016
New update on the extraction efforts. Looks like we’re going to be here for a while longer.

http://marsrovers.jpl.nasa.gov/spotlight/20090914a.html


Anyone want to venture a guess on how much of the Scamander Pan might get done?
vjkane
QUOTE (briv1016 @ Sep 14 2009, 10:44 PM) *
New update on the extraction efforts. Looks like we’re going to be here for a while longer.

http://marsrovers.jpl.nasa.gov/spotlight/20090914a.html

Having written a few press releases myself, I interpret the following as it ain't likely to happen:

"We are proceeding very cautiously and exploring all reasonable options," Callas said. "There is a very real possibility that Spirit may not be able to get out, and we want to give Spirit the very best chance."

I would love to have my fears proven wrong...
djellison
They said the same thing back with previous embedding events.

Don't read more into it that there is.
CosmicRocker
They may have said things similar to that in the past; but seriously, they have never before said anything even remotely similar to the following...

QUOTE
"Tests on Earth simulating Spirit's predicament on Mars have reinforced understanding that getting Spirit to rove again will be very difficult."


That, of course, is nothing new. This much has been obvious for quite some time now. I'm not normally a big fan of complex computer modeling, but I am hoping and praying that the model runs will point the way.
Sunspot
QUOTE (djellison @ Sep 14 2009, 11:08 PM) *
They said the same thing back with previous embedding events.

Don't read more into it that there is.


But this isn't like previous embedding events - they only have five turning wheels for a start.
Astro0
*cough*
Reminder....Tartarus!
5 operating wheels.
2 off the ground.
Still got out!

As Doug said..don't read more into this than is being said.
djellison
QUOTE (Astro0 @ Sep 15 2009, 11:24 AM) *
Reminder....Tartarus!


And Tyrone

Is this the worst that Spirit has seen?

Almost certainly.

Do we know for a fact that she can't get out?

Certainly not.

People are condemning the rover to this sand pit - when no serious attempt has even been made to extract her yet.

PaulM
http://marsrovers.jpl.nasa.gov/spotlight/20090914a.html

,contains the following words:

"We are proceeding very cautiously and exploring all reasonable options," Callas said. "There is a very real possibility that Spirit may not be able to get out, and we want to give Spirit the very best chance."

I think that leaving Spirit where it is for another few months might not in reality give Spirit the best possible chance. My reasoning is that Spirit is damaged by temperature cycling each night. Spirit (and also to a lesser extent Opportunity) could easily be rendered completely immobile by a cracked solder joint or a cracked wire at any time.

The current favoured extraction strategy might well work and if it was tried now rather than in two months time then this could give Spirit an extra two months of useful mobile life.
djellison
QUOTE (PaulM @ Sep 15 2009, 12:53 PM) *
http://marsrovers.jpl.nasa.gov/spotlight/20090914a.html
if it was tried now rather than in two months time then this could give Spirit an extra two months of useful mobile life.


Or could actually condemn it to its entire remaining lifespan (whatever that might be) to this sand pit.
MahFL
Cracked soldering and or wires could have happened at any time during the mission. If it does happen I guess you then deal with it, but to try drive out "just in case of a crack" is not the best policy.
fredk
QUOTE (PaulM @ Sep 15 2009, 12:53 PM) *
I think that leaving Spirit where it is for another few months might not in reality give Spirit the best possible chance.

One critical factor that has to be remembered is the possible high-centreing. In my mind, this has always been perhaps the most important factor. If that wasn't a concern, presumably with enough wheel turns you would eventually get out. But if we get high-centred, we may be truly stuck. In the past the official releases sounded surprizingly unconcerned about this to me, suggesting that the pointy rock might tip or move if we did get suspended on it. The more recent releases have been emphasizing the importance of trying to avoid getting high-centred. For example, from the recent update:
QUOTE
An additional round of testing was added to the September schedule to gain more detailed assessment of how to move Spirit while avoiding putting the rover's center of gravity directly over a rock that is touching or nearly touching the rover's underbelly.

I think this is very prudent. I'd much rather not risk Spirit on the ability of the rock to tip or move.
marsophile
If Spirit is stuck, and if spinning the wheels does dig in deeper, then there may be some final science value to be obtained from digging as deep a trench as possible in what seems to be an interesting location. wheel.gif
Hungry4info
QUOTE (marsophile @ Sep 15 2009, 03:38 PM) *
If Spirit is stuck, and if spinning the wheels does dig in deeper, then there may be some final science value to be obtained from digging as deep a trench as possible in what seems to be an interesting location. wheel.gif


It will go down until it touches the rock underneath it (if it isn't already) then no more.
Stu
3D view from recent MI images... interesting detail... lots of flecks and chips of brighter material...

http://twitpic.com/hxatn
marsophile
QUOTE (Hungry4info @ Sep 15 2009, 02:07 PM) *
It will go down until it touches the rock underneath it (if it isn't already) then no more.


Unless the pointy rock is at the center of gravity of the rover, Spirit should tend to slide off it as it digs, shouldn't it? (Or perhaps lean to one side.) Is it believed that the rock is located at the center of gravity?
Juramike
I think that would depend on the friction between the rock and the bottom of the rover as well as the weight distribution among the wheels.

The rock will take more of the load until the wheels hit a new equilibrium, but the wheels should still support some of the load. If the rock supports much of the load, the amount of gripping power the wheels would have would be VERY decreased.

Just like high-centering your mom's Plymouth Valiant while booney-hopping with your buddies on a Friday night in high school (for example).

marsophile
QUOTE (Juramike @ Sep 16 2009, 09:08 AM) *
The rock will take more of the load until the wheels hit a new equilibrium, but the wheels should still support some of the load. If the rock supports much of the load, the amount of gripping power the wheels would have would be VERY decreased.


We are not talking about gripping to move the rover now; we are talking about excavating loose soil. As long as the wheel is supporting some load, it should continue to excavate what is believed to be powdery soil. Unless the rover is well-balanced on the rock, it seems it should eventually tumble off. Or if the rock is also sitting on quicksand-like soil, it might be pushed down by the weight of the rover. (Or the rover might be impaled by the pointy rock. Yikes!)
Steve Holtam
QUOTE (Juramike @ Sep 16 2009, 10:08 AM) *
Just like high-centering your mom's Plymouth Valiant while booney-hopping with your buddies on a Friday night in high school (for example).


It seems to me like it would be much more difficult to high-center a five wheeled vehicle then a four wheeled car on two axles. I can't even imagine a scenario that would allow the rover to be perfectly high-centered on that pointy rock. It would have to dig down with all five wheels, and then dig out the sand from those five spots and then just happen to be perfectly balanced on the point.

It would must likely have to do the above process dozens of times, tilting and pivoting randomly each time until a moat would be dug around the entire pointy rock as all five wheels push sand out of the way. Then we would be stuck.

I'd still rather them try that as a last resort then being stuck forever here.
Keatah
QUOTE (Steve Holtam @ Sep 16 2009, 11:16 PM) *
It would must likely have to do the above process dozens of times, tilting and pivoting randomly each time until a moat would be dug around the entire pointy rock as all five wheels push sand out of the way. Then we would be stuck.



No we would not be stuck. Yes a moat would be created, and as the moat gets deeper the rover's angle of tilt (for want of a better term) would increase, and additional pressure would be applied the wheels lowest on the downward part of the rover, giving enormous traction. The rover would be suported by the rock tip and one or two wheels. The rover could keep going in circles till it becomes un-centered and slides off the rock tip. And we'd be in a whole new position from which to work from.

It does not seem that the rock would penetrate the web, more likely the rock would crack crumble and wear down a little.

Unless the rock's point is in the exact center of the rover, there will always be a wheel (or two) touching soil. This could be advantageous.

I would guess there would be a real danger of the rover tipping if the moat got too deep.

I suppose, assuming the rock is steadfast and can support the rover, that this is the only way out. Otherwise we have a brand new weatherstation!
James Sorenson
What is the likelihood that the rock will simply just press down into the soil due to the weight of the rover as the rover is sinking more and more, and take off little or no weight off the rover? Is this rock loose?
dvandorn
It's impossible to tell if the rock under the WEB is a relatively small rock that is "floating" on top of rather loose, unconsolidated dust, or whether it's the tip of a rockberg, so to speak. If it's the very top of a rock that's large enough to be firmly grounded, it is possible to put so much weight onto it that you reduce the effective weight on the wheels to the point where you'll never get any traction out of them.

Me, I think that rock will push down into the sand and not carry very much of Spirit's weight. But that's just a gut-level feeling; when looked at objectively, I doubt there's any way to know for sure except by going ahead with an extraction attempt and seeing what happens.

-the other Doug
Bhas_From_India
>> Me, I think that rock will push down into the sand and not carry very much of Spirit's weight.

I think the same. Sand is very soft here. May be we wouldn't have had this much sand here, if it was hard and a projection from the base.
There is very good chance of it going down by 'couple' of inches due to Spirit's weight....
Hungry4info
QUOTE (Keatah @ Sep 16 2009, 08:52 PM) *
Unless the rock's point is in the exact center of the rover, there will always be a wheel (or two) touching soil. This could be advantageous.


I just had one of those deep "Whoa ... " moments reading that. The ones that make you step back and think of things in a whole new light, you know what I mean?

Under the assumption that the rock is sturdy and can support the weight of Spirit, and assuming the rock is sufficiently toward the centre of the rover (not necessarily the exact centre):
If Spirit does accidentally have all its weight resting on it, what if they did indeed turn all the (working) wheels, set them spinning, and let the rover just rotate around on the rock. If Spirit rests on the rock, and the rock is firmly in the ground, it's not like Spirit is going to sink any further. Spirit rotates its wheels sufficiently out of the sand trap and they catch some harder ground, pushing the rover upward, off the rock, and somewhat out of the trap. Then we're in a much better situation to get out. Am I making any sense? huh.gif

Is this crazy? rolleyes.gif
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