Spirit Mission 2009 and onward

Page 7 - Seeking answers about space? Join the Space community: the premier source of space exploration, innovation, and astronomy news, chronicling (and celebrating) humanity's ongoing expansion across the final frontier.
Status
Not open for further replies.
X

xXTheOneRavenXx

Guest
I think I may have a solution on how to free Spirit. Yes, this is coming from a "common" person with absoluty no experience in the field of space vehicles. However a similiar solution does work with vehicles. What is one thing Spirit needs... traction, correct? Yes the solution may cause damage to the arm, however may get the rover mobile again. If the digging tool could be used to dig a form of trench along the front edge of the front wheel which is lower down the embankment, then place either part of the arm itself or an instrument under the front underside of the wheel (up against the wheel itself). Leaving the arm in this position, give a slow forward moving command, just enough to bring that wheel over the arm. Continuously conducting this maneouver back and forth each wheel as an action "foot-hold" should be enough to free it. It's kind of like using a peice of shingle to unstick a car from on a very slippery surface. If the tires of the rover are rubber, then it should be able to grip the metal surface of the arm. Yes, it will take several maneouvers, but our rover has a greater chance at being freed.

There is that, or if the arm can reach enough small gravel-sized rocks to place in a hole it'd dig in front of the tires would also give the rover enough traction to spin free. It does appear in that image that there are several of these size rocks available in close proximation to the rover.
 
3

3488

Guest
Re: talk of lifting MER A Spirit using the arm.

Please remember that the arms on the MERs are not as strong as the one that is on Phoenix Mars Lander (which was or could still be strong enough to tip the entire craft over).

The MER arms may have enough strength to remove some of the pressure on the front wheels, but are not strong enough to actually lift Spirit. The arm on Phoenix Mars Lander was designed to dig into martian tundra, where as the arms on the MERs are mainly to place intruments onto surfaces, rather than dig (apart from the RAT).

As the xXTheOne RavenXx correctly pointed out, traction is the key, to actually physically move Spirit onto firmer ground. Whether or not the arm can be moved & used to push small rocks under the front wheels is currently unknown, whether or not there are enough small rocks within reach to achieve this aim, I dunno. Perhaps JPL are or have already thought of this.

Below Sol 2,143 image, showing how entrenched the front wheels are.

Front HazCam. Sol 2,143.


Andrew Brown.
 
X

xXTheOneRavenXx

Guest
Well, as we all can easily determine that driving the rover towards the depth of the image is not going to work without traction. Using the arm to lift the rover is not going to work... however I had wondered if they could dig out in front of the tires enough that either it could be filled with small rocks, and if not can the arm be extended enough to be layed across this dug "trench", and the tire grip that portion of the arm layed before it, (rather than the arm exerting any force) and utilizing the traction grip the tire has the arm to pull itself forward. If need be, the tire could literally drive over a portion of the arm... then move the arm from now behind the tire and place it back in front of it (digging another trench if need be) to gradually provide the driving tire sufficent traction to pull the rover forward is all I meant. Yes, this may damage the arm... however it may not. Depending if the arm can hold the weight of being driven over, and how far it can reach.
 
M

MeteorWayne

Guest
Raven

The arm is not a "digging" arm. It has no tools for digging. It is an arm strictly used to position instruments in contact with surfaces to be tested.

Perhaps you have it confused with the Phoenix arm, which was indeed designed for digging.

Once you drive over the instruments on the arm, what's the point of moving? You have no tools to do any more science other than taking pictures!
 
M

Mee_n_Mac

Guest
Is there a recent picture of the clearance (???) under the rover ? At one point it appeared as there was a small gap btw the underbelly and a rock. These latest pics look (to me) to have Spirit sunk even deeper. Once it's on the rock I fear it's a goner. You'd have to find a way to fill in under the wheel(s) so as to raise the rover at that point. I'm not sure how that could be done outside of Raven's idea about pushing rocks (or dirt ?).

As for ruining the arm ... it's kind of a "so what" situation. Stuck as Spirit is, that arm and it's instruments won't be of much use, especially if funding is cut due to immobility. At some point you take bigger risks because you have no option. I believe the RAT is worn out, what other arm instruments remain working ?
 
M

MeteorWayne

Guest
From Emily Lakdawalla of TPS:

http://www.planetary.org/blog/article/00002307/

Just a Few More Approaches to Try for Extrication

"The list of remaining maneuvers being considered for extricating Spirit is becoming shorter. Results are being analyzed Wednesday, Jan. 13, from a drive on Sol 2143 (Jan. 12, 2010) using intentionally very slow rotation of the wheels. Earlier drives in the past two weeks using wheel wiggles and slow wheel rotation produced only negligible progress toward extricating Spirit...


Pending results of the latest drive, the rover team is developing plans for their final few attempts, such as driving backwards and using Spirit's robotic arm to sculpt the ground directly in front of the left-front wheel, the only working wheel the arm can reach. Such activities may take several sols to implement, but time is getting short as winter approaches and the team needs to focus on Spirit's winter survival.

The amount of energy that Spirit has each day is declining as autumn days shorten on southern Mars. If NASA does determine that the rover will not be able to get away from its current location, some maneuvers to improve the tilt toward the winter sun might be attempted...

Of course, using the arm to do anything, including science, jeopardizes future science; so late in the mission, and being mindful of Opportunity's broken shoulder motor, the arm motors have to be regarded as "consumables." Still, using it to do anything that's not science is, at least, trading not-science for science, and depending on how hard they push it, could shorten its life further...""
 
E

EarthlingX

Guest
So they still expect to do science with the arm, even if rover stays there. I guess there is no use of rover with not functioning arm, or is the rest enough to keep the project alive ?
 
M

MeteorWayne

Guest
It can still serve as a weather station, assuming it gets enough power. The question is would it be worth funding such an extension if no other science can be done. Maybe they'll just check in once in a while.
 
C

centsworth_II

Guest
"Spirit could continue significant research right where it is," said Ray Arvidson of Washington University in St. Louis, deputy principal investigator for the rovers. "We can study the interior of Mars, monitor the weather and continue examining the interesting deposits uncovered by Spirit's wheels."

A study of the planet's interior would use radio transmissions to measure wobble of the planet's axis of rotation, which is not feasible with a mobile rover....

"Long-term change in the spin direction could tell us about the diameter and density of the planet's core," said William Folkner of JPL. He has been developing plans for conducting this experiment with a future, stationary Mars lander. "Short-period changes could tell us whether the core is liquid or solid," he said.

http://www.nasa.gov/mission_pages/mer/news/mer20091231.html
 
3

3488

Guest
Hi centsworth_II,

That is a good point regarding the precise tracking of Spirit as Mars rotates the help pin down the nature of the interior.

Mars Pathfinder & Phoenix Mars Lander were also used to this effect. If Spirit is really stuck, then this could be an unexpected boon for the mission.

As already pointed out, images can be used to monitor the weather, atmospheric opacity, how lighting varies due to dust, clouds, seasonal changes, if power permits night time astronomy observations such as Phobos & Deimos eclipses, looking for martian meteor showers, twilight observations, etc.

There is still much Spirit can do if stuck. Of course we hope that is NOT the case, but if it is, there is still a potentially rewarding mission to be had. Just hope that she could survive the Martian Winter in this position.

As Wayne says it is dependent on funding & IMO this would be well worth full funding.

Andrew Brown.
 
C

CommonMan

Guest
Re: Spirit is Moving!!!

Thats great, but it isn't out of the hole yet. :(
 
A

adman69

Guest
That is very exciting news! I just posted this same type of thing on the Phoenix thread, but, NASA has had uncanny luck at Mars. The rovers are still kicking ass and I really have no doubts that if they play this smooth and patiently, that they will free Spirit and she'll move on for several more years.

I do believe though that if they can't get her out in the next month then she's doomed. I can't see her lasting the winter with no power to internally heat herself. Let's just hope NASA is successful!
 
E

EarthlingX

Guest
Ho ho ho, it is moving :) This is much better than mm in the wrong direction plus down.
I'm growing one more hand to have more fingers crossed .. :cool:
Good job Spirit team !
 
3

3488

Guest
I agree with adman69,

Spirit is making real progress at last. Just hope it is not too little too late.

It will be the southern Martian Winter Solstice on Thursday 13th May 2010, when the sun will be at it's lowest in the north at Midsol & will be the shortest day / longest night, in the martian southern hemisphere.

Spirit really needs to be repositioned well before then, being tilted due north.

Andrew Brown.
 
3

3488

Guest
HI EBM,

Yes it is the underside of the solar arrays.

Lets hope that more progress will be made.

Sol 2,151, clearly shows that Spirit is slowly coming out of the dust trap. The right whell is almost completetly exposed now.


Andrew Brown.
 
3

3488

Guest
Sol 2,153. Front HazCam.

Looks like Spirit has made further progress.


Andrew Brown.
 
C

CommonMan

Guest
3488":1eus57jj said:
Sol 2,153. Front HazCam.

Looks like Spirit has made further progress.


Andrew Brown.
I have been stuck in the sand down by the river where I fish many times. I have to tell you that sand looks a lot like river sand by the sandbar. What I mean by that is that it’s very lose sand. Even if the rover gets out of the spot it is stuck in, it may not get far. What that means to me anyway is where it is stuck, was once probably wet ground. Just speaking as a southern Texan river rat, not a sceincetist.
 
E

earth_bound_misfit

Guest
Cool, that is looking more promising. My fingers are crossed little buddy.
 
E

EarthlingX

Guest
CommonMan":2tcurifh said:
I have been stuck in the sand down by the river where I fish many times. I have to tell you that sand looks a lot like river sand by the sandbar. What I mean by that is that it’s very lose sand. Even if the rover gets out of the spot it is stuck in, it may not get far. What that means to me anyway is where it is stuck, was once probably wet ground. Just speaking as a southern Texan river rat, not a sceincetist.
She doesn't need to get far. Just to turn towards the Sun will do for a very long time.
(I m getting cramps on my finger crossed feet, but it's worth it :)
 
Status
Not open for further replies.

ASK THE COMMUNITY