Ace PFY skills
So, am I getting this right, turn it off and back on and it should be fine?
Software issues prevented the fourth scheduled flight of NASA's Mars Ingenuity helicopter. The delay was not unexpected nor prevents future flights. In fact, NASA reassured a waiting world that the helicopter is "safe and in good health." The reason for the failure is also known: a software bug that results in a watchdog …
Works every time...
Somehwere, buried deep within the rumbling bowels of Redmond, an MS black-ops world-domination skunkworks team, featuring the world's greatest moustache-twirling super-villain developers, is tirelessly beavering away on plans to update Windows on any machine not running windows.
To ensure a system stays alive, a watchdog timer periodically resets it unless interrupted by valid code. It should be timed to prevent it interfering with functionality, but as systems get more complicated this becomes quite a hard nut to crack. In such a case as this, the watchdog appears to time out (and reset the system) before a valid process has completed. Reducing the time the valid process takes is indeed the quick fix, but it appears in this case that they're having to wait a variable time for some real time event. A difficult enough problem on Terra Firma, but at that distance I take my hat off to NASA.
> Reducing the time the valid process takes is indeed the quick fix, but it appears in this case that they're having to wait a variable time for some real time event
Just speculation on my part but maybe they tried to put too much into one step - for good reasons - and are now splitting it into two steps so that the watchdog can be safely reset in between?
That split probably has knock-on effects so a bit of a pain when you want to do it in a hurry.
> The rover’s flight control software has been stable and healthy for almost two years, and why mess with a good thing there?
A good question.
If the only (small) issue is that 15% of the time the helicopter won't initialise into flight mode, it doesn't sound too risky to simply wait a while and try it again.
Isn't that the answer that software support gives, 90% of the time?
Hopefully also they don't hit the end of the 30-day flight window before they fix/test it, otherwise Perseverance may be off on the rest of its mission.
I know it's not part of the plan, but it would be cool if they could put Ingenuity into a "follow me" mode where it keeps (say) 20m away in a series of hops from Perseverance until it finally breaks.
I suppose that the risk is that something breaks and it then hits the rover and jams/breaks something.
What a cool job to have!!
> it would be cool if they could put Ingenuity into a "follow me" mode...
Range anxiety is the problem. Short flight times and very long recharge times.
Maybe NASA could tap into the 15 billion dollars Biden is proposing for 500,000 new charging stations and install some on Mars.
Depends on how much power is used before initialisation fails - it may have to go into a recharge state for a while before retry.
I find it surprising that a 15% chance of invalid faults being flagged under no-fault conditions wasn't discovered and fixed during pre-flight testing. After all the basic requirement is that it flies and this fault report causes it not to fly. When something is sitting on Mars you don't really want to be sorting out whether a fault flag is real or not before you try again as the result could terminate the mission ...
It turns out that testing such a thing is hard. You don't actually completely know the environmental conditions where it's going to end up, and to the extent you do know them they're very hard to reproduce on Earth: you can easily get the temperature and pressure correct (which they did) in a hypobaric chamber, but getting the gravity completely correct is very hard indeed. You can get it half-correct by attaching, essentially, a string to the top of the vehicle and offloading a lot of its weight, which they did, but it's still sitting in a 1g gravitational field so things like how much the blades droop won't be correct. The only way to get that correct would be to lift your hypobaric chamber high above the ground and then lower it down with an acceleration of roughly 6m/s^2 for long enough to do the test inside it. That's ... hard.
AFAIR Ingenuity was always intended as an advanced prototype. It's there on this mission to learn what works and what doesn't. If it achieves any serious scientific results, that's a very welcome bonus.
Fingers firmly crossed that it does achieve those results, but it's already a tremendous success in this initial phase.
Managing remote computers is a pretty common thing in today's IT world, whether it's some industrial kit or a stack of servers running in a data center half-way across the country or globe.
Those happily have the option of a call-of-shame to a colleague or support person whenever the gear in question does not come back online in a healthy state after a reboot. Here it sounds like the nearby rover is the closest thing that JPL's engineers have to a 'call support to push the power button on the server' fallback :)
Yea, but I still have that moment of panic.
Even though I've done it hundreds of times, I know it will work and how long it takes to boot. But, I guess, I'm not the only one who suffers 'time dilation' during the wait so it never comes up quite when expected. The alternative of looking at a clock seems to make it even worse.
Boy, I wonder how many of Ingenuity's engineers have a pacemaker ...
.... but well within Human Reach*
If the only (small) issue is that 15% of the time the helicopter won't initialise into flight mode, it doesn't sound too risky to simply wait a while and try it again.
Isn't that the answer that software support gives, 90% of the time? .... Pete 2
Works well every time in the past, Pete 2, and there no reason to expect IT to change in the future in order to forestall and prevent OS failure and programs crashing with massive cracks exposing great hacks.
All could very easily be totally lost to NASA Mars Command and Control if drifted and gifted to Commanding Control from elsewhere foreign and alien for Future Flight Operations with the Benefit of Hindsights Providing Advanced Future Planning with Immersive Live Presentations ...... with Media BroadBandCasting Exemplary Demonstrations with ACTive Virtually Augmented Realisations.
Have they considered that Overtaking Plan a Possibility if a Current Actuality is difficult to accept and enjoy is definitely different and attractively engaging of both the diffident and indifferent and revolutionary evolutionary.
* Easy Peasy with an OE Instruction Manual to Follow with Indicative Pictures Aiding Greater Understanding of Core Systems Working.
It is really interesting (but a little annoying) to see that one device that NASA has sent into space written using existing "modern" software engineering practices and semi off-the-shelf has been the most problematic. And I don't think it is to do with the radiation shielding either.
So from the looks of it, they are using C++ so I can't quite blame Python and its stupid dependency hoarding.
Is it some janky reverse engineered driver that they have had to use for Linux because the hardware vendor doesn't give a crap? Perhaps I can blame the fact that SoC are hobbyist toys rather than anything reliable?
Likely they will look into it and avoid this kind of development methodology entirely. It would be interesting if they could put out an experience paper so I can point future clients towards it as evidence that some ideas are simply no good for decent engineering.
Although I've no idea what software engineering the copter runs, I agree that there is something 'modern' about it that doesn't sit quite right with me. From the article on the systems it runs there seems to be a GHz-class CPU running a normal OS, plus multiple MCUs acting - essentially - as sensor nodes, which seems to me (granted as an occasional embedded dev but not in anything so critical or quite as complex as this) rather overkill to run a helicopter. Obviously one would set the WDT to attempt to encompass the potential range of spinup times, but having such a complex system would be expected to increase the probability of something being missed in testing.
Although it would be inappropriate to compare the HW in this machine to that required to land something on the Moon, one does still think that a lesser applications processor, running something more realtime/bare metal with direct control over its sensors, would have been more suited to the idiom of 'plan for the expected, but expect the unexpected' that space is.
>Perhaps I can blame the fact that SoC are hobbyist toys rather than anything reliable?
"SoC", or as I'd call them, "microcontrollers", aren't hobbyist toys. They're actually serious bits of kit that used in practically anything that moves these days. For a motor controller, for example, the processor is almost an afterthought, its used to initialize and integrate the specialist peripherals that perform tasks like determine shaft speed and torque, run the control loops and generate the waveforms needed to actually drive the motor. The resulting device is a functional block, one of many in a big system, and it really helps the layering/structuring to be able to treat it as a black box with well known properties. You can integrate a lot of this into an applications processor but you increase task interdependencies which are difficult to predict and so manage. (Get it wrong and you get a watchdog timeout.......you can see where this going.)
I should also give a nod to these 'hobbyists'. One of the side effects of making high performance microconttollers and related software environments like the Arduino available to anyone is that it widens the net of people able to work at this level. This benefits everyone -- the hobbyists, the professional (aka "hoibbyist who gets paid (a lot) to indulge their hobby"), manufacturers (you tendt o use parts families that you're familair with). Its win-win all the way. These 'amatuers' can be very inventive and are quite able to show a seaoned pro a thing or two. Worth having on a team.
No, I don't believe they are using micro-controllers for the helicoptor. It is an off-the-shelf SoC. The Qualcomm Snapdragon 801 SoC.
Whilst what the engineers have done is clearly very fantastic. It seems to be that the more disciplined traditional embedded style of development is still better compared to the new stuff. This alone was a really interesting experiment and got useful results.
Why remote? It's easy enough to insert a gateway into the link that simply holds any packet for the required time (dependent on the distance between Earth and Mars at that moment, so 4 to 24 minutes approximately) before passing it on.
For a lab test involving a five-node cluster with one member that would be about 40km away from the nearest two after its real-world deployment they were simply installed in a single rack including all the comms gear, and a 40km spool of fiber on top of the cabinet. Saved a lot of walking when simulating error conditions.
They certainly have copies on Earth, and they certainly test things on them. Whether they book time on the JPL space simulator and set everything up to look as much like Mars as possible in it depends on whether it's available and how long that takes, I would think (copies of Ingenuity certainly were tested in it). I would imagine the reason they can talk about the known 15% chance that they'll hit the watchdog timer is because they tested to work that out, for instance.
I would not be shocked to find out the data transmission is a bit slow and erratic and eventually someone finds out its downloading updates from earth all the time.
Also why is the footage so crap? A nice 360 of the landscape including the lander would seem possible. First its uploaded full fat from drone to the lander . Crunched down into some sort of 50mb file then sent to earth.
I have the impression nobody works at nasa but rocket engineers and all they do is stand at blackboards doing sums.
If you did some research – any research – before making a fool of yourself that would make you look less of a fool. Ingenuity has more than two orders of magnitude (so, say between 100 and 500 times) more computational resources than Perseverance: it would be insane not to do image processing on Ingenuity. Ingenuity's radio link with Perseverance is also pretty narrow: Perseverance can transmit (via relays in Mars orbit) at up to 2mb/s to the DSN, while the Ingenuity/Perseverance link is something like 1/8 of that. Finally, it may not have occurred to you that the people who designed and flew Ingenuity kind of want it to succeed: showing that a helicopter can be useful on Mars by making the early flights a bit cautious is a lot more important to them – and to us – than having it crash on the first flight because it was trying to do some complete rotation in order to get a cool, but useless, image.
As for your 'all they do is stand at blackboards doing sums' comment? (a) we need more people doing that and (b) fuck you.
Is it possible that every other reader is too mature to pretend to believe that when Ingenuity is in flight mode, radio communication is turned off... like flight mode on my cellphone?
I've been here some time, so I say no.
You're all pretending to be too mature to pretend to believe etc.
Vote as your conscience allows, but I know the truth. ;-)
Pondering what services to switch off to keep your laptop going just that bit longer? NASA engineers can relate, having decided the Mars InSight lander will go out on a high: they plan to burn through the remaining power to keep the science flowing until the bitter end.
The InSight lander is in a precarious position regarding power. A build-up of dust has meant the spacecraft's solar panels are no longer generating anywhere near enough power to keep the batteries charged. The result is an automatic shutdown of the payload, although there is a chance InSight might still be able to keep communicating until the end of the year.
Almost all of InSight's instruments have already been powered down, but the seismometer remains active and able to detect seismic activity on Mars (such as Marsquakes.) The seismometer was expected to be active until the end of June, at which point it too would be shut-down in order to eke out the lander's dwindling supply of power just a little longer.
NASA is finally ready to launch its unmanned Orion spacecraft and put it in the orbit of the Moon. Lift-off from Earth is now expected in late August using a Space Launch System (SLS) rocket.
This launch, a mission dubbed Artemis I, will be a vital stage in the Artemis series, which has the long-term goal of ferrying humans to the lunar surface using Orion capsules and SLS technology.
Earlier this week NASA held a wet dress rehearsal (WDR) for the SLS vehicle – fueling it and getting within 10 seconds of launch. The test uncovered 13 problems, including a hydrogen fuel leak in the main booster, though NASA has declared that everything's fine for a launch next month.
The software on ESA's Mars Express spacecraft is to be upgraded after nearly two decades, giving the orbiter capabilities to hunt for water beneath the planet and study its larger moon, Phobos.
Mars Express was launched on June 2, 2003, and was initially made up of two components: the Mars Express Orbiter and the Beagle 2 lander. Unfortunately, the lander failed to make contact with Earth after it was released and arrived at the surface of the Red Planet. It is presumed lost. The orbiter, however, is still working after 19 years in service, spinning around Mars.
Now, engineers at the Istituto Nazionale di Astrofisica (INAF), Italy, are revamping the spacecraft's software. The upgrade will allow the Mars Express Orbiter to continue searching for water locked beneath the Martian surface using its MARSIS radio-wave instrument and monitor the planet's closest satellite, Phobos, more efficiently. MARSIS is today operated by INAF and funded by the Italian Space Agency.
NASA has chosen the three companies it will fund to develop a nuclear fission reactor ready to test on the Moon by the end of the decade.
This power plant is set to be a vital component of Artemis, the American space agency's most ambitious human spaceflight mission to date. This is a large-scale project to put the first woman and first person of color on the Moon, and establish a long-term presence on Earth's natural satellite.
NASA envisions [PDF] astronauts living in a lunar base camp, bombing around in rovers, and using it as a launchpad to explore further out into the Solar System. In order for this to happen, it'll need to figure out how to generate a decent amount of power somehow.
Sadly for NASA's mission to take samples from the asteroid Psyche, software problems mean the spacecraft is going to miss its 2022 launch window.
The US space agency made the announcement on Friday: "Due to the late delivery of the spacecraft's flight software and testing equipment, NASA does not have sufficient time to complete the testing needed ahead of its remaining launch period this year, which ends on October 11."
While it appears the software and testbeds are now working, there just isn't enough time to get everything done before a SpaceX Falcon Heavy sends the spacecraft to study a metallic-rich asteroid of the same name.
NASA's Moon rocket is to trundle back into its shed today after a delay caused by concerns over the crawlerway.
The massive transporter used to move the Space Launch System between Vehicle Assembly Building (VAB) and launchpad requires a level pathway and teams have been working on the inclined pathway leading to the launchpad where the rocket currently resides to ensure there is an even distribution of rocks to support the mobile launcher and rocket.
The latest wet dress rehearsal was completed on June 20 after engineers "masked" data from sensors that would have called a halt to proceedings. Once back in the VAB, engineers plan to replace a seal on the quick disconnect of the tail service mast umbilical. The stack will then roll back to the launchpad for what NASA fervently hopes is the last time before a long hoped-for launch in late August.
Rocket Lab has sent NASA's Cislunar Autonomous Positioning System Technology Operations and Navigation Experiment (CAPSTONE) spacecraft on its way to the Moon atop an Electron rocket launched from New Zealand.
The launch had been subject to a number of delays, but at 09.55 UTC today, the Electron lifted off from Rocket Lab's Launch Complex 1 on the Mahia Peninsula of New Zealand.
The Mars Ingenuity helicopter is in need of a patch to work around a failed sensor before another flight can be attempted.
The helicopter's inclinometer failed during a recommissioning effort ahead of the 29th flight. The sensor is critical as it will reposition the craft nearer to the Perseverance rover for communication purposes.
Although not required during flight, the inclinometer (which consists of two accelerometers) is used to measure gravity prior to spin-up and takeoff. "The direction of the sensed gravity is used to determine how Ingenuity is oriented relative to the downward direction," said Håvard Grip, Ingenuity Mars Helicopter chief pilot.
Pic When space junk crashed into the Moon earlier this year, it made not one but two craters on the lunar surface, judging from images revealed by NASA on Friday.
Astronomers predicted a mysterious object would hit the Moon on March 4 after tracking the debris for months. The object was large, and believed to be a spent rocket booster from the Chinese National Space Administration's Long March 3C vehicle that launched the Chang'e 5-T1 spacecraft in 2014.
The details are fuzzy. Space agencies tend to monitor junk closer to home, and don't really keep an eye on what might be littering other planetary objects. It was difficult to confirm the nature of the crash; experts reckoned it would probably leave behind a crater. Now, NASA's Lunar Reconnaissance Orbiter (LRO) has spied telltale signs of an impact at the surface. Pictures taken by the probe reveal an odd hole shaped like a peanut shell on the surface of the Moon, presumably caused by the Chinese junk.
Interview NASA has set late August as the launch window for its much-delayed Artemis I rocket. Already perched atop the booster is the first flight-ready European Service Module (ESM). Five more are in the pipeline.
Airbus industrial manager Siân Cleaver, whom The Register met at the Goodwood Festival of Speed's Future Lab, has the task of managing the assembly of the spacecraft, which will provide propulsion, power, water, oxygen and nitrogen for the Orion capsule.
Looking for all the world like an evolution of the European Space Agency's (ESA) International Space Station (ISS) ATV freighter, the ESM is not pressurized and measures approximately 4 meters in length, including the Orbital Maneuvering System Engine (OMSE), which protrudes from the base.
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