I wonder if they really are sinking in after all. If you look at that picture in detail, there appears to be a dune crest rising up slightly near the right wheel. However, it also appears to be dropping off as we get to see more of it and as Opportubity moves slowly forward.

They are not sinking (much)! Oppy is driving in an arc as described by the mission managers. Seems that the arc is centered around close to left front wheel. At the rear, the rightmost edge of the left wheel is getting close to the side of the trench.

Well, at least that's how it looks like to me :-)

oops...I meant to say that I dont think it is sinking in that much after all......it might "look" that way because the soil has been rising up near the right wheel because of the dune crest that has become visible. I think it is now dropping away again.

So the latest images that appear at exploratorium show the result of the planned 12m drive?

Are these tracks made from Oppy ? Or something else ?

http://qt.exploratorium.edu:16080/mars/opp...HHP2134L2M1.JPG

It's just the pancam looking down on the right front wheel

That is the track that Oppy made just before getting stuck. Because of the lighting direction, some of the image features can look inverted. (at least for me anyway)
Here is the same image rotated 180 degrees.

http://i6.photobucket.com/albums/y207/gary...HHP2134L2M1.jpg

Gary

If you mean the trench looks wider than the wheels thats because the middle wheels are not in the same line as the forward and rear wheel, they are offset toward the centerline.

If you compare this Pancam SOL 469
http://marsrover.nasa.gov/gallery/all/1/p/...H5P2134L2M1.JPG

With this SOL 470
http://marsrover.nasa.gov/gallery/all/1/p/...HHP2134L2M1.JPG

We can clearly see how good the progress is getting now

I should have known better, this is the Nth time this happens to me.
The minute I read garybeau mentioning a 180o rotated image, I realized I was fooled once more
I guess I should not look at MER imaging while working

Thanks to everyone for their comments.

In a German astronomy forum there is a woman who is specialising in this phenomenon of inverted views. So far the poor woman isn't able to look for craters in moon pictures - she has only hills in her mind

I experienced exactly the same problem for many years when I was younger; I had to patiently educate (force) my mind to invert images to correct this tendency (however, sometimes happens again! ).
I'm convinced that, years later, this "discipline" helped me to efficently see stereograms, especially crossed-eyes ones; many other peoples aren't able to do this unnatural operation...
I'm curious about other experiences!

Personally, I've found that a life-time enthusiasm for 'top shelf' gentlemen's magazines has assisted me enormously in my stereo perception... ...even in non-stereo images!

Seriously, though, it's surprising how many people just don't seem able to do the crossed-eye trick at all. Perhaps when we see the IMAX-3D MER special there'll be the opportunity (geddit?) to seduce a few more folk to the 3D camp!

Well, I *hope* there's an IMAX 3D MER film coming...

Bob, your stereo perception "even in non-stereo images" is very interesting!
It would be really cool to have a 3D film of Mer mission...

About 10% of the population is more or less Stereo-Blind, about the same fraction that has some form of color-blindness. I have amblyopia and cannot fuse images to get stereoscopic perception at all. Bit of a pain for a one time <and still amateur> planetary geologist.

I tried for 4 months and then one day it worked. It's very simple really and I think more people should try it. But I must say I haven't been able to learn it to friends and such.. stereomadness..
Nico

Ok, y'all have lost me here. If I may ask, what's up with this "rotate it 180 degrees" thing? What is it said to accomplish?




Hehe, I've been able to cross my eyes since I was in elementary school. My eyes will "uncross" when I get tired, and am still trying to read something. Doing the opposite was always easy - maybe because I used to read so much; my eyes were used to that motion.

Under certain light conditions in an image, I may look at it and confuse intrusions with protrusions.
If I don't realize it immediately, the image looks strange and incomprehensible. A rotation by 180o of the image restores my perception of depth (and whatever is dysfunctional in my brain ) , and I can see the image for what it really is.

Before we get to far OT here...

What do you think will be the next moves in the extraction process?

When I have a printed page and this problem crops up, I can usually fix things by rotating the picture so as to match the lighting in the room. Namely, orient it so the shadows in the picture fall away from the main light source in the room where I am. You could try this with a computer image as well, although I recommend rotating the image and not your computer.

Forgive me for the previous blank post. Yes I am definitely a newbie. I was going to suggest that it would be nice to get back on-topic, but it appears I have just exacerbated the problem.

To answer the previous on-topic post, If I were skiing, I'd trudge out of the this crust-covered fluff, and traverse in the valleys as much as possible. Since the rovers don't have the benefit of momentum, they'll have to test every crossing dune very gingerly (e.g. command a meter, visually sense slip, change direction if necessary). I think it's going to be slow stuff (<20 meters/day type progress).

I can't wait until we send humans to orbit Mars and remotely control an entire fleet of rovers in real time. Even these rovers would be about 10x more productive. I will die a happy man if I see that in my lifetime. (oops, I changed topics...er.. Curses! Hoisted on my own petard!)

The rover has moved quite a bit overall:

http://qt.exploratorium.edu/mars/opportuni...HTP1314R0M1.JPG

http://qt.exploratorium.edu/mars/opportuni...HTP1214R0M1.JPG

It does appear to be digging it's way out... I wonder if this is what happened during testing on Earth?

I'm distinctly worried that, when it reaches the end of the gardened, churned-up tracks, Opportunity will just continue swimming through the soft dusty undersoil. I can't see that there will be an 'edge' that the wheels can catch on, to lift out of the dust layer.

Put another way: breaking through the permacrust was like going through a thin sheet of ice on top of a swamp. It may be that the rover is doomed to stay in the swamp, progress being made by just nibbling away at the crust without climbing up on it again.

Of course, the stuff at the base of the dune may be better going, more compacted, easier to climb up on. I certainly hope so.

-- Martin

That was something that I thought about too. As the dune slopes downwards though perhaps there will come a point where, particualrly if the rover doesn't sink any more, the wheels are less buried in the soil and they will drive up out of the trenches they've made.

http://qt.exploratorium.edu/mars/opportuni...HHP1214R0M1.JPG

If you look at the last drive the right front wheel is already starting to rise and I believe that is a sign of what to come very soon

The left is going a bit down though, but it also has the most dirt to shovel

I've been trying to understand the 'means' of entry in getting stuck - based on the fact that the front and rear wheels track just about together - and the middle wheels are about 1/3rd of a wheels-width inboard of that. It's plausable that they're not nearly as dug in, but that they're not taking much of the load. It would be interesting to see some graphics based on the articulation of the rocker/bogie (they have this data, it has been reconstructed into movies in the past)

Doug

In the attached images, the blue position is the original "stuck" position, and the overlaid positions are after drives on sols 463-468.

There we go - THAT's what I'm talking about Middle wheel is nowhere near as deep as the rest.


Doug

... and these images doesn't include drives from 469 to 471, which may add some 12 cm (my guess) of forward movement.
The current situation would be even better.

Tesheiner

Now that's some cool stuff

Looks like my idea of the bogie movement was correct

Didn't Oppy drive today?

Oppy seems to move faster with a bit more grip on Sols 470-471. Looks good to me

and the right one as well

Dirk

Agree, is clearly accelerating now!
Look for example to this animation of back/right wheel in the last 4 days (using only half of frames):
http://img74.echo.cx/img74/4821/sol467471rr8dv.gif
Go, Oppy, go!

It looks like the middle wheel is starting to climb onto the churned dirt.


The animations that follow are also encouraging. It looks like it's making excellent progress. I guess they'll have to include a snowplow attachment on the MSL.

Thanks, that is exactly what we need to see. We'll be out in no time now!

James

It would be interesting to know how long it took the test rover to escape the drift, and whether it behaved in a similar way to what we are seeing with Opportunity right now.

Did it continue to "dig" through the soil like Oppoertunity is doing....or after a few sols did it drive up out of the trenches on to the surface.

The amount of fill in the left wheel trench is greater than that in the right without any spill to the sides. Does this reflect :

different volumes of material due to different densities before they were disturbed,

deeper pentration by the right wheel below the surface,

better traction on the left wheel moving more material forward as it backs out.

or is there a larger pile of loose material in the way of the right wheel as it continues to back out?

I thought I read somewhere that they were reversing out in an arc, in which case one side would move more than the other.

Yes - instead of trying to fight the 7 degree toe-out on that FR wheel, i think they're 'giving in' to it and letting the rover turn to the left as it pushes back

If they were to go straight back down their own trenches, the wheels could end up just churning all the way. By turning the craft a little to 'push' against the left side of the trenches, it gives them something 'new' to have a bite at and pull up out the trenches I guess.

Doug

The rear wheels seem to dig themselfs deeper all the time, which is bit alarming. I dont think it means the middle wheels are getting higher, but they both get down as they churn forward. I do not yet think they are on the clear waters even than there is accelerating movement. As they dont actually gather any momentum because the speed is so slow, progress might stop just as quick as it started.

Yeah, according to the description I read of the maneuver they decided to use, they were going to exit back the way they came, but in a left arc (left in their current direction of travel, which happens to be "forward" since they were driving backward when they got stuck).

It also occurs to me that they don't want to just back straight up, since that puts them heading right back up a dune they had just climbed -- possibly putting the front wheels on that dune before the rear wheels clear the sand trap. A left-arc exit lets them increase the amount of time the three left-side wheels spend on the (presumably) firmer inter-dunal soil. It also, it would appear to me, gets more wheels into the inter-dunal soil more quickly, and for a longer time.

Of course, it *does* sort of look like a right-hand arc would be a better choice to maximize wheels in the inter-dunal soils, but the stuck steering actuator would probably make that pretty difficult, especially pulling out of the trap...

-the other Doug

From: http://www.space.com/missionlaunches/05052...ers_update.html



Let's hope the rate picks up soon

Thr first image in oppy's rear_hazcam page for today the 25th gave me quite a jump.

What the!! Where, what!!! Ooooooohhhhhh.
http://qt.exploratorium.edu:16080/mars/opp...BJP1311L0M1.JPG

And this is wonderful!!
http://qt.exploratorium.edu:16080/mars/opp...00P1214L0M1.JPG

Looking back at those images, it's a relief that Oppy didn't venture into the dune trap in the middle of Endurance. We realize this now how dangerous this would have been.

I was looking some image sent from 'today' which shows it still on the lander. It's amazing they didn't transmit and purge these earlier with the mem problems.

I looked at the images of where Opie got stuck. We can get a better perspective on the area. I would not have seen any problem with the direction it took. Sadly one has to wonder if they should continue onward into the etched terrain or pick a different target.

At least some genuine new images just came down...

Still making good progress

http://qt.exploratorium.edu:16080/mars/opp...IZP1214R0M1.JPG

http://qt.exploratorium.edu:16080/mars/opp...IZP1314R0M1.JPG

Is it just me or are they starting to sound less optomisitc about getting out?

I wouldnt say less optimistic. Clearly they still think they can get out - and saying it'll take a week, or two weeks, is consistant with the progress we've been making and consistant with the predictions from Steve.

Doug

He also said:



"If Opportunity gets free"

Until now it has always been "When"

But with the steady progress I have no doubt it will get out... They just need to gun it some more...

Perhaps this ripple overlies a large trough similar to Anatolia.

"I was looking some image sent from 'today' which shows it still on the lander. It's amazing they didn't transmit and purge these earlier with the mem problems. "

Could one conclude that the massive downloads of the last few days were intended to lighten the rover and assist in getting her unstuck?