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What computer and software is used by the Falcon 9? (2015)

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Re: What computer and software is used by the Falcon 9? (2015)

#21

Post by ryder9 »

nullifidian wrote: post #15

Sounds kinda disappointing/irresponsible. Chromium is an overly complex, relatively buggy piece of software. For example I recently experienced a bug where a text I selected was significantly offset from what should have been selected given the pointer position (on linux), a misclicky kind of bug. Considering that the majority of Crew Dragon's controls are through touch screen, maybe even manual docking(not sure, but…

you sure showed those people who worked hundreds of hours and have more knowledge of their system than some rando in this 'intellectual' website

Re: What computer and software is used by the Falcon 9? (2015)

#23

Post by 7leafer »

ryder9 wrote: post #21
nullifidian wrote: post #15

Sounds kinda disappointing/irresponsible. Chromium is an overly complex, relatively buggy piece of software. For example I recently experienced a bug where a text I selected was significantly offset from what should have been selected given the pointer position (on linux), a misclicky kind of bug. Considering that the majority of Crew Dragon's controls are through touch screen, maybe even manual docking(not sure, but…

you sure showed those people who worked hundreds of hours and have more knowledge of their system than some rando in this 'intellectual' website

you sure gave enough arguments to beat those of the parent.

Re: What computer and software is used by the Falcon 9? (2015)

#24

Post by je42 »

aetherspawn wrote: post #4
jamespetercook wrote: post #2

“They use Chromium and JavaScript for the Dragon 2 flight interface.“ This is the most interesting part for me being a web dev! How likely do you think this is?

Just because they do, doesn’t mean you should. I’m running an automotive firmware project at the moment and there are such things as software integrity levels, and each time you add something to the stack you create quite a large amount of testing and validation and process that needs to be followed. And it’s pretty much impossible to take something existing like Chromium and certify it to what you need. The architec…

I think it is not helpful to call out that their architecture is "wrong" and their process is "wrong".

The attribute "wrong" is very opaque.

As somebody who doesn't have your background, i cannot follow you. I have no idea about automotive and space software requirements.

Since there are many aspects that lead to choices of a system architecture it requires more words to explain why a choice is not a good choice for the job.

Re: What computer and software is used by the Falcon 9? (2015)

#26

Post by davedx »

nullifidian wrote: post #15

Sounds kinda disappointing/irresponsible. Chromium is an overly complex, relatively buggy piece of software. For example I recently experienced a bug where a text I selected was significantly offset from what should have been selected given the pointer position (on linux), a misclicky kind of bug. Considering that the majority of Crew Dragon's controls are through touch screen, maybe even manual docking(not sure, but…

Why not Javascript? I would argue that a good usable UI in a spacecraft is a good thing, and Javascript is a great language for building UIs

Re: What computer and software is used by the Falcon 9? (2015)

#27

Post by raverbashing »

nullifidian wrote: post #15

Sounds kinda disappointing/irresponsible. Chromium is an overly complex, relatively buggy piece of software. For example I recently experienced a bug where a text I selected was significantly offset from what should have been selected given the pointer position (on linux), a misclicky kind of bug. Considering that the majority of Crew Dragon's controls are through touch screen, maybe even manual docking(not sure, but…

I don't see why.

Chromium is being used in the UI. Not on critical flight software.

> maybe even manual docking

It isn't done manually

> C++ and linux do not strike me as mission critical piece of software / language either

A lot of flight software is done on C++, as you even mentioned. In the end, your best reliability partner is not using a language that's only know by fewer people.

What would be a good "mission critical piece of software"? QNX (with no memory protection?). Linux is fine. I suppose they're not firing Ubuntu out of the box and running that with no customizations.

Separation of concerns and redundancy usually beat correctness on the long term (which doesn't mean they didn't test the correctness of the system).

Re: What computer and software is used by the Falcon 9? (2015)

#28

Post by TeMPOraL »

fsh wrote: post #11
aetherspawn wrote: post #4

Earlier quoted context omitted.

Just because they do, doesn’t mean you should. I’m running an automotive firmware project at the moment and there are such things as software integrity levels, and each time you add something to the stack you create quite a large amount of testing and validation and process that needs to be followed. And it’s pretty much impossible to take something existing like Chromium and certify it to what you need. The architec…

I believe the choice of Chromium and JS for the UI simply shows that the astronauts are merely inconvenient payloads. Gagarin's first flight was already fully automated 59 years ago.

Should've paired them with a dog. As the old joke goes, the astronauts are there to feed the dog; the dog is there to bite the astronauts if either of them tries to touch any of the controls.

Re: What computer and software is used by the Falcon 9? (2015)

#29

Post by fit2rule »

gumby wrote: post #8

Interesting that it’s three identical processors running he same software. I remember just the automated Vienna central train station used a pair of machines, x86 and SPARC, one running the logic in a procedural language (Chill) and the other running in a logic language (Prolog). They didn’t want both processors to share any code, and therefore potentially the same bug.

That hasn't been the case in Vienna for some years, so you must have seen that setup a decade or so, ago.

These days its THALES-built systems running SIL-4 rated code in a best 2-of-3 or 3-of-5 voting system, and each of the nodes can be either PPC, Arm or x86 - but not all the same, for architecture reasons. These systems produce a vote that has to match, or else the system shuts itself down. Chill and Prolog haven't been shipped in that capacity in decades...

(Disclaimer: worked for Thales on these systems, had to help remove a ton of Chill code, fix bugs in its compiler, etc.)

Re: What computer and software is used by the Falcon 9? (2015)

#30

Post by mofosyne »

nullifidian wrote: post #15

Sounds kinda disappointing/irresponsible. Chromium is an overly complex, relatively buggy piece of software. For example I recently experienced a bug where a text I selected was significantly offset from what should have been selected given the pointer position (on linux), a misclicky kind of bug. Considering that the majority of Crew Dragon's controls are through touch screen, maybe even manual docking(not sure, but…

Unlikely that they are using javascript in the actual flight controller. Also under the screen they have a small amount of manual buttons that is likely to be seperate from the touchscreen interface logic.
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