Raspberry Pi In Space

mikejuk (1801200) writes "When British astronaut Tim Peake heads off to the International Space Station in November, 2015, he will be accompanied on his 6-month mission by two augmented Raspberry Pis, aka Astro Pis. The Astro Pi board is a Raspberry Pi HAT (short for Hardware Attached on Top), and provides a gyroscope, accelerometer, and magnetometer, as well as sensors for temperature, barometric pressure, and humidity. It also has a real time clock, LED display, and some push buttons — it sounds like the sort of addon that we could do with down here on earth as well! It will also be equipped with both a camera module and an infra-red camera. UK school pupils are being challenged to write Raspberry Pi apps or experiments to run in space. During his mission, Tim Peake will deploy the Astro Pis, upload the winning code while in orbit, set them running, collect the data generated and then download it to be distributed to the winning teams.

Comments

Quick question

[Echo_Hotel]

Is that raspi going to need radiation hardened chips or is that satellites only?

Re:Quick question

[Trepidity]

The ISS itself uses radiation-hardened computers, but these "AstroPI" are just using stock chips. The only thing different afaict is the custom peripheral board. I would guess the duration of the experiment, combined with it not really being a mission-critical part, makes radiation hardening not needed.

Re:Quick question

[ShanghaiBill]

but these "AstroPI" are just using stock chips.

With current technology, it is common for even stock chips to have some rad-hard features. For instance, many ICs are manufactured with depleted boron as a semiconductor dopant and in the borophosphosilicate glass insulating layer. This can dramatically reduce the number of soft errors, and adds little to the cost, since depleted boron is not particularly expensive, and only small quantities are needed. It is also possible to fix some problems in software, by running periodic checksums on blocks of memory.

Re:Quick question

[ShanghaiBill]

Radiation hardened hardware has shielding and larger components.

That depends on the degree of hardening. It is not black and white. You are never going to make it 100% impervious.

You simply can't harden chips like the RPi uses

You most certainly can. There are some simple fixes that can make a big difference.

Checksumming doesn't fix errors, it detects them.

Once you detect an error, you can often fix it. You can re-run a calculation, or reload a program from flash, or whatever.

Re:Quick question

[citizenr]

You know what else is stupid? You :)
Old hat NASA engineers have been repeating that same old story about hardening for years. They all said it cant work, will be unreliable, is a waste of time and money. All until Phonesat was tested and worked.
http://www.space.com/21036-spa...

Today there is over 100 NONhardened satellites in orbit
http://www.wired.com/2014/10/p...

They cost thousands instead of millions of dollars, and work just fine. You can listen to an interview with one of the founders/engineers here:
http://www.theamphour.com/220-...

Re:Quick question

[RockDoctor]

For instance, many ICs are manufactured with depleted boron as a semiconductor dopant and in the borophosphosilicate glass insulating layer.

Since you're talking about isotopically purifying a material, that's going to be a damned sight more expensive than normal-isotope-mix boron. You've got the relatively large mass difference working on your side - 7.7% mass difference (borane) compared to (238+6*19)/(235+6*19) = 0.08% difference (UF6) - but you're still looking at a pretty big job. Even simple heavy water is thousands of times more expensive than normal reagent grade water (11.8% mass difference for D2O versus H2O).

I hadn't thought about the (relative) reactivity of 10B from a radiation-sensitivity point of view. But we've been using it to date the exposure of rock surfaces to the sky for a couple of decades now, and a damned useful tool for archaeological and geomorphological studies it is too. It's up there with thermoluminescence for dating fire damage.

Hope he doesn't lose power

[gavron]

Pis are great.
But when the power drops.the filesystem on the SDcard is corrupt.
Then the Pi is dead with no hope of doing anything unless you brought a spare SDcard or something to mount/fsck/correct it with.

If I was going into space I'd take a Droid or an iPhone. That way I can play
Angry Birds In Space in space.

E

Re: Hope he doesn't lose power

[Anonymous Coward]

I keep hearing this but I always just pulled the plug, no problems.

Re: Hope he doesn't lose power

[Anonymous Coward]

Did you pull the plug so that the SD card could go out with dignity?

Re: Hope he doesn't lose power

[Anonymous Coward]

Never lost it. It is still running a modified Bodhi float, no issues.

Re: Hope he doesn't lose power

[Anonymous Coward]

Have you bothered to ask the SD card if it was OK with such extreme life-prolonging treatment? Or it's you who cannot let it go?

Re: Hope he doesn't lose power

[BitZtream]

Then you're lucky.

The RPi will corrupt SD cards even mounted read-only. It has no hardware write protection and does mysteriously stupid things on power loss. The behavior is well known, which is why you keep hearing it.

Re: Hope he doesn't lose power

[0100010001010011]

With as cheap as you can get memory these days why doesn't someone put 16 or 32 GB on the same board and a way to TFTP boot and stop making me deal with SD cards.

Re:Hope he doesn't lose power

[Christian Smith]

Pis are great.
But when the power drops.the filesystem on the SDcard is corrupt.

That's probably more a function of your crappy SDCard. These things are cheap, and probably not engineered to handle partial writes that would corrupt the card.

I do wonder why though, is it so difficult to order writes so that what's committed to FLASH is always recoverable?

Re:Hope he doesn't lose power

[itzly]

Manufacturers are already struggling with other requirements, such as maximum possible density, and a reasonable number of erase/write cycles. Safe write ordering interferes with the other requirements, and is not something the average consumer notices.

Re:Hope he doesn't lose power

[WarJolt]

This has nothing to do with a RPi. It is a common file system problem.
RPi has 2 file systems.
      1. Fat32 for the bootloader, proprietary firmware and kernel
      2. Linux rootfs that can use many different kinds of file systems.

ext2 wasn't very good at handling unclean shutdowns.
ext3/4 are a little better.
fat32 is terrible.

Fortunately the fat32 partition doesn't need to be written very often, so you're good. Reads aren't dangerous.

What you really want to do is make sure your Linux kernel has an initramfs installed in the kernel image, so it can fsck and fix any file system errors if the partition wasn't cleanly unmounted.

http://wiki.gentoo.org/wiki/Cu...

There you go. Not a hardware issue.

Re:Hope he doesn't lose power

[gavron]

No, I'm afraid not. (And these are name-brand Class-10 cards).

When the corruption hits the Pi won't boot at all. No grub no kernel no initrd no monitor sync.
A fresh card fixes things. Restoring the image to the old card fixes it too.

We have near 100 of these in the field and while I've bench-powerfailed them to no avail,
out in the real world they die due to fs corruption.

E

Re: Hope he doesn't lose power

[Maxmin]

I have never, ever seen this happen. I run mounted read-write, read-only, multiple partitions.

I run RPis off batteries, UPSes and dirty apartment building power with cheap Chinese power adapters. I've seen every combination of power loss during reads, writes, to primary or temporary fs.

Never ever seen corruption. I smell PEBKAC, as in your choice of sd card.

Re:Hope he doesn't lose power

[Bearhouse]

I'm sure there's a Burma Shave in there...

Re: Hope he doesn't lose power

[Anonymous Coward]

I'm not the op, but I smell arrogant assumption in your reply that your sample of 1 hasn't encountered the same issue.
I work for a company and we actually trialled the Pi in a embedded application, we built out a lab with a common rail psu and climate control with four of them. 3 bricked themselves regular with sd card issues, and the fourth on the same psu sat there without issues for months being soak tested under load. We tried the cards that went bad in the "bad" units in the good unit, and again, it never corrupted it. The only thing we could find different were they were purchased at different times, so we assumed we'd got a bad batch. But you need root cause analysis to be able to be confident with this.
We tried to raise this with the foundation, but were told that they would only investigate if we could exactly reproduce when and how to create the issue, and were the only one to have reported this (downright blatent lie).
We dumped them and went with an alternative, but please, don't continue to support the "bad card must be PEBKAC" meme pushed out by the foundation on the forums.
I saw this topic, and wondered if I would be the one highlighting the elephant in the closet, but it seems other sufferer's at the hand of bullshit have arrived first.

Re: Hope he doesn't lose power

[Anonymous Coward]

nope,
This has happened to me twice both times after power failures.

Re: Hope he doesn't lose power

[Anonymous Coward]

So much this. Cheap SD cards are an absolute blight. Unreliable, slow, noncompliant, and failure prone.

Since most users are clueless, the only product differentiation available is price. We all know what happens to product quality when the race-to-the-bottom comes in to play.

And more often consumers, in their infinite wisdom, blame their devices when their 5 dollar grey market (and likely counterfeit) ebay sourced memory card causes problems.

This is the real reason, FYI, that SD card slots are disappearing from phones.

Re:Hope he doesn't lose power

[Anonymous Coward]

I use my raspberri pi daily for the mission-critical task of downloading youtube videos and watching them on my HDTV (raspbian / omxplayer, ext3). haven't ever bothered properly shutting it down, except for maybe a handful of times. Five months later, the system still boots fine from the SD card and there has been no noticeable data loss on the videos.

Granted, the videos are stored on a USB jump drive, so the changes to the SD card file system are negligible.

Re:Hope he doesn't lose power

[amxcoder]

I've had a couple Pi's also exhibit FS corruption on power loss as well. Not everytime, but each time you pull the power plug it's a roll of the dice. I was using them running RaspBMC OS and XBMC on top of them for media servers and I've seen them corrupt several times. Each time, there was no booting afterwards, would fail on boot and require a reflash of the SD card in order to get them back up and running.

Re:Hope he doesn't lose power

[RockDoctor]

We have near 100 of these in the field and while I've bench-powerfailed them to no avail, out in the real world they die due to fs corruption.

Hang on, let's get that straight : if you pull the power when they're on the bench, then they don't fail, but if they suffer a power fail in the field they do suffer corruption and freeze/ hang/ fail to boot?

Obviously you've tried this, but are you sure that you're pulling the power on the bench while they're in mid-write? Because if you're doing ostensibly the same thing in two circumstances, but with different results, then I'd have to wonder if you're actually doing THE SAME THING both on the bench and in the field.

The way you've described it, it shouldn't do that.

Are the field and lab conditions - e.g. temperature - also the same. I could see temperature having a significant effect on write speeds on (flash) memory. It sounds perplexing. And quite worrying if your troubleshooting isn't replicating something that seems so simple. I know that troubleshooting can be a real time-sink, but if you're getting lots of these fails then the time to service the fialed field modules must add up too.

Are the Pis also under the same load conditions - data-logging, streaming, whatever - on the bench as in the field?

SPACE!

[Dukenukemx]

"Oooh! Ooh! Hi hi hi hi hi. Where we going? Where we going? Hey. Lady. Where we going? Where we going? Let's go to space!"

Do they run ipv6?

[NotInHere]

http://science.slashdot.org/st...

Re:This is what Hitlers goal was

[Anonymous Coward]

GETTING THEM INTO THE BODY OF EVERYBODY IS A FAR MORE IMPORTANT GOAL FOR HITLER:
http://science.slashdot.org/co...

Filter error: Don't use so many caps. It's like YELLING.

Filter error: Don't use so many caps. It's like YELLING.

Hope he doesn't lose power

[Anonymous Coward]

I've pulled the plug on my pi a couple of times, no problems. Last week I had it plugged into a battery, taking a picture every minute for a time lapse project until the battery ran out. Turned out fine. Maybe you've just had crappy SD cards, or bad luck.

Inside the station or outside?

[Anonymous Coward]

Either way I don't think pressure and humidity sensors are going to be very interesting.

Cosmic Rays

[BitZtream]

It'll be awesome ... it'll run for exactly 8 seconds before radiation corrupts every register beyond function and it has to be reset. Cosmic Rays for the win!

Re:Cosmic Rays

[marked]

Yes, because that quite clearly happens with all the laptops, tablets, and mobile phones that have already been up there.

Oh, wait.

Re:Cosmic Rays

[dougmc]

The ISS is well below the Van Allen radiation belts and well within the Earth's magnetic field (which deflects many of the charged particles headed towards the Earth) so the level of cosmic radiation it gets is not *that* high, and the metal of the ISS blocks most of of that.

And if a Raspberry Pi does get its registers corrupted by cosmic rays ... it's not a tragedy. Nobody dies -- it's not mission critical.

In any event, they use pretty standard (but old -- last I heard, they still ran Windows 95) laptops on the ISS and they work fine. It would be interesting to know how much more often they experience failures and errors on the ISS due to radiation compared to how much they experience here, but I don't know if anybody has measured that. (My guess is that NASA has, though I wouldn't know where to look for the data.)

Re:Cosmic Rays

[jandrese]

It also sucks that every astronaut we send up there dies in like 3 days from radiation poisoning from the apparent containment-core levels of radiation the ISS flies in...

Re:Cosmic Rays

[BitZtream]

Theres a difference between radiation poisoning and flipping a few bits.

Re:Cosmic Rays

[BitZtream]

In any event, they use pretty standard (but old -- last I heard, they still ran Windows 95) laptops

And what size is the process they used to make those chips, versus the chips that are used in the ARM core of the Raspberry Pi and its attached memory?

The smaller you go the more of a problem it is. Older chips work because everything in them is larger, knocking one electron out of place on a pentium is WAY different than doing it on processors where you have very few atoms to work with.

Re:Cosmic Rays

[dougmc]

The reason they use older laptops is not because of the density of the chips but simply because they're known commodities -- any quirks they have have already been figured out and they get the job done. Getting anything certified (for mission critical purposes) is a very time consuming process, and once it's done ... the item is no longer state of the art, that's just the nature of the beast.

The Raspberry Pis don't have to go through the same certification process, though of course if they were expected to only work "for eight seconds" I think NASA would have told the people sending them up that to pick something older. I'm guessing that NASA knows a bit about the radiation environment up there and advises people who send up experiments appropriately.

And as others have said ... humans are living in the same environment for months at a time -- it can't be *that* bad.

Re:Cosmic Rays

[Anonymous Coward]

That's what the clones are for.

Re:Cosmic Rays

[jandrese]

It's really the same mechanism. In one case the high energy rays impart enough energy to charge or drain a gate, and in another high energy rays impart enough energy to break a DNA bond. The parent was talking about being continually hit with enough high energy rays to instantly crash a normal computer, which is well above the amount you need to kill a person.

Re:Cosmic Rays

[citizenr]

Yes, and >100 NON hardened satellites in orbit today work only thanks to magic, right?

https://www.planet.com/

Re:Cosmic Rays

[itzly]

Most high energy rays don't hit the DNA molecule. It's a small target. And even when they hit it, there is rarely any noticeable effect on long term. Usually the cell just dies (if it can't be repaired). Chips are much less robust in comparison.

Sending the RasPi eggheads in space.

[Anonymous Coward]

Actually sending the Raspberry PI ceo in space with a rocket to uranus would be a good idea after their stupid anti-nerd and anti-gamer comments.

Re:Astro pis...

[Applehu Akbar]

Clearly no marketing creative oversaw the coining of that name.

Dare I Say It...

[Anonymous Coward]

A Pi in the sky?

Re:Astro pis...

[FreeRadicalX]

What, no "Pi in the sky" jokes? I'm disappointed.

inside ISS isn't "real space"

[Anonymous Coward]

Real "flight hardware" has to deal with conduction cooling (not that convection works in zero G, but the thermal environment inside ISS isn't all that different from an office: fans work).
And, of course, ISS has people on it, so the radiation dose is pretty benign.

Lots of test data on consumer devices

[Anonymous Coward]

Check out papers at the MAPLD conference, etc. Lots and lots of consumer stuff gets dragged up to ISS, and it mostly works. Relatively few permanent failures (latchup, usually). Some soft errors: power cycle and resume.

What about power consumption?

[Maxmin]

I read the linked article, nothing on power. RPi is a power-hungry little beast. Sure, A+ reduces it a bit, and you can turn off various onboard devces.

But it still sucks down a lot of power. I wonder what ISS's power budget is.

Re:What about power consumption?

[hackertourist]

ISS power budget is 75-90 kW.

Good start

[tehcyder]

But to be a perfect Slashdot story, the flight should be crowd-funded, and the astronaut should 3D print a Raspberry Pi in space.

Plus regular contributor Bennett Haselton should be invited to cogitate on the potential copyright issues in space.