[Space] NASA - Mars Exploration Rover MER-A "Spirit" - Update Thread

[GioFX]

SATURDAY, JANUARY 24, 2004

0330 GMT (10:30 p.m. EST Fri.)

Despite two commands from engineers on Earth to enter sleep mode to conserve power, Spirit remained awake all day Friday, Mission Control reported late tonight.

"Shortly before (3 p.m. EST), controllers were surprised to receive a relay of data from Spirit via the Mars Odyssey orbiter. Spirit sent 73 megabits at a rate of 128 kilobits per second. The transmission included power subsystem engineering data, no science data, and several frames of 'fill data.' Fill data are sets of intentionally random numbers that do not provide information," NASA officials said.

"Spirit had not communicated successfully through Odyssey since the rover's communications difficulties began on Wednesday."

[GioFX]

0400 GMT (11:00 p.m. EST Fri.)

While efforts to revive the Spirit rover continue, the sister-craft Opportunity remains on course for its Saturday night/Sunday morning landing on the Red Planet.

Opportunity's touchdown at Meridiani Planum -- a smooth, flat plain near the equator halfway around the planet from Spirit's Gusev Crater landing site -- is scheduled for 12:05 a.m. EST (0505 GMT).

The landing site for Opportunity was selected because scientists believe there is an Oklahoma-sized area of gray hematite, a mineral that usually forms in the presence of water.

"Gray hematite is a mineral indicator of past water. It is not always associated with water, but it often is," said Joy Crisp, project scientist for the Mars Exploration Rover project.

The rover will search for the material to determine if the hematite layer comes from sediments of an ancient ocean, from volcanic deposits altered by hot water, or from other environmental conditions in the planet's distant past.

"Hematite forms in a number of different ways on Earth but most of them involve the action of liquid water," added Steve Squyres, the rovers' principal investigator. "So you can think of the hematite mineral signatures being kind of a beacon that's saying to us, 'hey, water may have been here.' Now we don't know how it formed, it could have been a hydrothermal system, could have been a lake, we're not sure. But it says, mineralogically, water."

Opportunity carries the same set of science tools as Spirit -- multiple cameras, a rock-grinding device and sophisticated instruments to determine the composition of soil and rock samples.

"We want to know if the grains of hematite appear to be rounded and cemented together by the action of liquid water or if they're crystals that grew from a volcanic melt. Is the hematite in layers, which would suggest that it was laid down by water, or in veins in the rock, which would be more characteristic of water having flowed through the rocks," Crisp wonders.

NASA's orbiting Mars Global Surveyor discovered a couple of years ago that Meridiani Planum featured gray hematite, prompting researchers to send a rover to the locale.

"The area where we are going has 10 to 15 percent gray hematite. What are the other materials found with the hematite? Clays and carbonates would indicate there had been water in the area. If the area had been volcanic, you would expect to see other types of minerals like olivine and pyroxene," Crisp says.

"We're very interested to know if this region could have been like Yellowstone, with hot springs, so we'll be looking to see if there are other minerals in the area such as those at Yellowstone."

The battle cry of NASA's Mars exploration program is "follow the water." Proving that Mars once had liquid water would help to determine if the planet could have supported life long ago.

"Knowing just how the hematite on Mars was formed will help us characterize the past environment and determine whether that environment was favorable for life. One big question, of course, is whether life ever started on Mars. This mission probably won't tell us that, but it may well lead to future mission that can answer that question."

We will provide live updates on this page throughout the landing!

[gpc]

Spirit s'è rincoglionito...?

[GioFX]

Originariamente inviato da gpc
Spirit s'è rincoglionito...?

sembra... è quasi sicuramente un problema del software.

[gpc]

Originariamente inviato da GioFX
sembra... è quasi sicuramente un problema del software.

Bah, che roba... leggevo (non ho visto se c'e' anche nei documenti che hai riportato) che potrebbe essere un problema con il software che gestisce uno dei motori degli specchi del TES (si chiama cosi', no? mi sto rincoglionendo pure io... troppo studio... devo avere qualche bug nel sistema operativo... ). Chissa'... speriamo che lo rimettano in sesto.

[maxsona]

Non potevano creare un software di back up nel caso quello di serie si fosse rincoglionito ?

[gpc]

Originariamente inviato da maxsona
Non potevano creare un software di back up nel caso quello di serie si fosse rincoglionito ?

Un sistema che si accorge di problemi e cerca di risolverli in automatico c'e', perche' infatti come si legge negli articoli il rover sta resettandosi automaticamente cercando di far ripartire il software per eliminare il problema... solo che il problema resta.
Non hanno idea di cosa possa essere precisamente, perche' e' una cosa abbastanza casuale e i 73Mb di dati ricevuti fanno capire ancora meno... boh...

[GioFX]

Originariamente inviato da gpc
Bah, che roba... leggevo (non ho visto se c'e' anche nei documenti che hai riportato) che potrebbe essere un problema con il software che gestisce uno dei motori degli specchi del TES (si chiama cosi', no? mi sto rincoglionendo pure io... troppo studio... devo avere qualche bug nel sistema operativo... ). Chissa'... speriamo che lo rimettano in sesto.

il problema principale pare essere legato all'impossibilità da parte di Spirit di muovere l'high gain antenna (necessario per "cercare" il sole e poi puntare correttamente verso la terra), se questo sia dovuto ad un problema software o hardware non è dato sapere ancora.

[GioFX]

Sojourner (11 kg) e MER (185 kg):

[gpc]

Ma porca...! Non credevo proprio che fosse cosi' grande!

[GioFX]

Originariamente inviato da gpc
Ma porca...! Non credevo proprio che fosse cosi' grande!

Se va avanti di questo passo il prossimo che mandano sarà un SUV!

[gpc]

Originariamente inviato da GioFX
Se va avanti di questo passo il prossimo che mandano sarà un SUV!

Io dico che se ne perdono un'altro si rompono le palle e ci mandano un carro armato, "non si sa mai..."

[Spazius]

Originariamente inviato da gpc
Io dico che se ne perdono un'altro si rompono le palle e ci mandano un carro armato, "non si sa mai..."

un bell avrams alimentato a uranio impoverito e via....cosi se trovano gli alieni sanno come affrontarli
cmqtasera leggendo questi aggiornamenti mi è venuto in mente che magari quando riprenderanno le trasmissioni visive vedranno un ambiente tutto bianco con gli alieni che ci girano in torno...

[GioFX]

Pasadena - Jan 24, 2004

NASA has been able to reestablish stable communications with the Mars Rover Spirit and begin receiving engineering data. This has allowed critical commands to be sent further isolating the issue. At this stage the problem has been traced to computer flash memory chips though the exact nature of this remains uncertain. However, NASA is now confident the issues can be worked around and Spirit could be rolling again within several weeks.

[GioFX]

2003 GMT (3:03 p.m. EST)

Pete Theisinger, Mars Exploration Rover project manager, says the team has made good progress overnight with Spirit. The rover's status has been upgraded from "critical" to "serious" condition.

Engineers are working on a theory that there is a problem between the flight software and the rover's flash memory.

We'll post Theisinger's briefing as soon as possible.

[GioFX]

2150 GMT (4:50 p.m. EST)

Rover project manager Peter Theisinger gave the following update on activities to diagnose Spirit's ailment and return the craft to working order:

"We made good progress overnight and the rover has been upgraded from critical to serious. We have a working hypothesis we are pursuing that is consistent with many of the observables and consistent with operations that we performed on the vehicle last night. It involves the flash memory on the vehicle and the software used to communicate with that memory.

"The processor on Spirit has three kinds of memory:

"There is the random access memory just like the memory in your computer, which is used basically in a real-time mode. And that memory is volatile, so when we turn off the rover at night that memory goes away.

"We have flash memory. That memory is just like the memory in a digital camera. It can also be read to and written from easily. But it has non-volatile characteristics -- the information that is stored there stays overnight even if the vehicle is powered down.

"And then we have we call double EPROM, which is electrically-programmable memory. That is more difficult to write to and read from, and we use that to store part of the flight software image.

"The vehicle normally uses the flash memory mostly for the storage and retrieval of engineering and the scientific telemetry. The software has to communicate with the flash memory -- has to open up files, establish file directories, close files in that flash memory. That process has to work correctly.

"We are capable of operating the vehicle without going to the flash memory in what we call a 'cripple mode.' That is name we have chosen -- you should not read too much into that. That basically tells the flight software that when it boots up, it should operate with its file directory out of the random access memory rather than the flash memory. That would avoid any issues that we might have with either the flash memory itself or the flight software that is used to write to it.

"Let me talk about the chronology of what happened in the last 24 hours. If you recall when we last talked at yesterday's press conference, we were attempting to shut down the vehicle because the batteries were becoming depleted. We had an apparent inability to shut down the vehicle last night, yesterday at the end of the Mars day, which is about the time of the press conference at 9 a.m. Pacific. That was in fact confirmed because later we had a UHF communications session with Odyssey where we got 73 megabits of data, mostly fill or garbage data, although we did get some fault data, some current, some 14 hours old.

"We did not know but thought we might go into low-power overnight if the batteries were fully depleted. When came up this morning we looked for the 9:30 Mars time communications window and it was not there, indicating, we thought, that we had gone into low-power. That would cause the vehicle to come up at 11 o'clock and tell us that.

"We, just prior to 11 o'clock, sent a command to the vehicle that said 'go into this cripple mode.' That is only done at the next reset, so then we sent a command to the vehicle that said 'and reset' in order to do that. And we timed it so that when the 11 o'clock session would start, we would begin to get that session at 10 bits per second indicating we'd gone into low-power. When the commands reached the spacecraft light-time away, it would send us into cripple mode, reset the computer and we would come up in the mode. And in fact that is precisely what happened.

"At that point, we commanded a one-hour communications session at 120 bits per second. That communications session happened as planned.

"The progressive set of resets that we were getting into every hour did not reoccur, leading us to conclude that our hypothesis is largely correct -- that is there is something involved in the flight software that talks to the flash memory that's causing this difficulty.

"Why that might cause us difficulty is because when the spacecraft first wakes up it needs to communicate with the flash memory to establish a file structure and when it goes to sleep and shuts down, just like you shut down your computer at home, it needs to go out to that memory and close all of those files and clean everything up. If it is unable to do that, it would not complete those tasks appropriately and will basically reset itself and not shut down.

"In the midst of that 120 bits per second, one-hour session, we decided to shut down the vehicle in order to replenish the batteries. We commanded the shutdown just prior to the end of the communications session so that we would see the communications session terminate early if we were able to operate it correctly. That happened. And we sent two post-shutdown beeps, which we expect not to hear if it is asleep but we would hear if it was not asleep, and we did not get those, once again confirming that the vehicle to the best of our ability to determine is now sleeping on Mars.

"We also yesterday as part of the command sessions during this period of time terminated tonight's UHF passes and reset the uploss timer. The uploss timer is a set of fault code that go into play when the vehicle thinks it has a communications problem and causes some things to switch state and we didn't want to get into that if we could avoid it. Both of those were confirmed to be successful.

"So we have a vehicle that is stable now in power and thermal. We have a working hypothesis that we have confirmed. The fault protection to the best of our estimation has worked as designed. It took us a lot to figure out what was going on, but we think everything has worked in the fault protection as we expected it to do.

"We have a go-forward plan. The cripple mode, which we can use every day, needs to be re-established every day because it loses the memory that that's the way it should start up. So every morning we will need to start up in cripple mode, so we need to establish an operational way of doing that every day for the next few sols (Mars days).

"We need to establish a high-rate link in order to be able to get much more data back, particularly if we want to read out the flash memory and determine what has happened. What we will plan to do is likely to use the Odyssey afternoon relay pass for that purpose prior to the afternoon shutdown.

"We need to then establish the contents of flash to find out what happened and then we need to move forward with the diagnosis and recovery of the vehicle capability based upon what we find there.

"Remember that this was all kicked off by Sequence 2502. That was the sequence that was using the elevation motor in the mast failing out, failing to complete (on Wednesday). We still do not know the details of why that happened and we need to do that.

"The mission consequences of this are uncertain at the present time. But I think that we feel that we probably have more capability left in the vehicle that we can establish than the worst-case scenarios by quite a bit. We still see a couple of weeks to determine what had happened and to rebuild our confidence into what is working on the vehicle and to get back closer to routine operations. I think we are probably like three weeks away from driving, I am guessing.

"The team will begin to go into double-shift operations probably a day or so after Opportunity's landing where we have a re-plan period and then an operational period as we begin to work through the forensics of this.

"But this is a very good news. We've established an ability to communicate with the vehicle reliably, we've established that in fact we do have controllability of the vehicle, can establish a good power and thermal state, our working hypothesis is one that we can work around with significant measure if it turns out our working hypothesis is correct. So a good day for an Opportunity landing."

[GioFX]

2106 GMT (4:06 p.m. EST)

"Spirit is still serious but moving toward guarded condition," rover project manager Pete Theisinger reports. "I think we got a patient well on the way to recovery."

In the past day, engineers have determined that Spirit's flash memory hardware is OK. A leading theory today is that a portion of the rover's software simply couldn't cope with all that was happening on Wednesday when the trouble began.

The rover's batteries are now fully charged and the craft shortly will be going to sleep for the night. But before nighttime it will be relaying data to the Mars Odyssey orbiter including engineering and diagnostic information.

Theisinger predicts that Spirit will resume driving around the surface in a couple of weeks.

Meanwhile, the Opportunity rover is operating properly following its landing last night.

[GioFX]

Bogged down software could explain Spirit's ailment

BY SPACEFLIGHT NOW
Posted: January 25, 2004

The group working to unravel the glitch with Spirit and return the rover to action has narrowed the possible cause of its trouble to three potentials, officials said Sunday afternoon.

"Spirit is still serious but we are moving toward guarded condition now," rover project manager Pete Theisinger said. "I think we got a patient well on the way to recovery."

The rover experienced a problem last Wednesday, disrupting communications with Earth and halting all science activities. The breakdown happened while Spirit was performing a calibration of motors on the Mini-TES instrument.

"The leading theory is that the file management software module in the software has gone to some condition that it could not cope with -- that it was not robust enough for the operations we were engaged in when we had the flaw on Wednesday," Theisinger said.

On Saturday, engineers began focusing on the rover's flash memory and the way the software communicates with the computer memory. To get the rover operating, it was told to avoid using the flash memory for now.

On Sunday, the team was able to reset Spirit's computer to the non-flash utilization mode, Theisinger said. Also Sunday, the ongoing diagnostics determined the flash memory hardware aboard the rover to be healthy.

"There are two other theories that are not as well in competition but cannot be discounted, and they are being worked by anomaly subteams," Theisinger added.

"One is there was some kind of error or hardware issue on the motor control board. That's the circuit board with the electronics that control the motors. That's being examined.

"Also...there was a solar event Wednesday and the timing of that is being looked at with respect to correlation to the onset of our problems. The flash memories are sensitive to high-energy ions and neutrons when they are being read from and written to, and we were certainly engaged in a lot of that activity that day."

Theisinger remains hopeful that Spirit will resume its exploration adventure of Gusev Crater by mid-February.

"I think we've got a patient well on the way to recovery, and I think we have a very good chance now we will have a very good rover when we are done getting this thing back up. Although, once again, it will take some time to make sure that we have completely characterized the problem and that we are able to check out all of the functionality on the vehicle.

"You can't take anything for granted here. So I don't expect to be driving for a couple of weeks, maybe three."

[devis]

"Also...there was a solar event Wednesday and the timing of that is being looked at with respect to correlation to the onset of our problems. The flash memories are sensitive to high-energy ions and neutrons when they are being read from and written to, and we were certainly engaged in a lot of that activity that day."

Verissimo, le memorie flash sono ancora troppo fragili. Avevo scattato una sessantina di foto in vacanza con la digitale e all'improvviso la scheda dava errori con la conseguenza di aver perso tutte le foto in memoria

Questo nel mio piccolo

[devis]

Gio,sai dirmi che hardware (cpu, qta ram ecc) monta il lander?