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Comment by voisin | Hacker News Reader

What does SpaceX use?

On 1-Aug-2017, Jinnah Hosein, who was the head of Software at SpaceX at the time, spoke to my company, Orbital Insight, in Mountain View, and I took some notes. I've never posted them anywhere, but below I'll post some unpolished bits.

WARNING: this was a lot longer and 'scattered' than I recall, apologies in advance.

DISCLAIMER: This was a casual talk and I casually took some notes, and it happened over three years ago as of this writing. In short, don't assume anything below is an accurate representation of what Jinnah said. As a long-time SpaceX fan, and as a much longer-time software engineer, I was super pumped during the whole talk, and was definitely not focused on accurate recording.

https://www.realms.org/spacex-talk-notes.html

PS: I know most of this veers way off topic, but for some reason I decided to take this opportunity to share this material.

PPS: The comment was too long to post, so you'll need to click the above link. Sorry about that. If someone would like to distill the on-topic parts into another comment, that would be fine.

> There is no defined systems integrator role at SpaceX. Everyone is responsible for carrying their system all the way through. They resisted the idea of handoffs.

> They saw that at NASA. Because of the handoff, it caused them to push reliability ratings way higher than needed, which added complexity and customization.

Very interesting!

also

> it took Elon six weeks to go from "OK let's land on a boat" to actually having a boat. The software VP guy didn't think it 'was a 2014 problem...definitely 2015'...people who had been there longer knew Elon would be able to get a boat quick. Definitely a 2014 problem.

then this

> So then they'd fly balloons off of the boat so they'd get low level wind data, said data would go to the vehicle and be used for control for the last few km.

So many gold nuggets. Thank you!

> So many gold nuggets. Thank you!

You're welcome! I'd forgotten most of this and so it was really fascinating reading over it again just now, especially in light of all that SpaceX has been doing over the past 3.5 years.

What was this line about?

>Facebook got jammed up because they had to re-write a lot of software under DO189B/C.

I have no damn clue. I did a quick Google of "DO189B/C" (and related..typos are definitely possible here) and nothing jumped out.

I typed this up 3.5 years ago, and didn't give a crap about Facebook one way or another at that time, so whatever was said there didn't stick with me at all.

Hopefully somebody else where can somewhat decode mystery string (that might have typos) based on context.

Probably this: “DO-178B, Software Considerations in Airborne Systems and Equipment Certification”

https://en.m.wikipedia.org/wiki/DO-178B

Very nice find, thanks! How do you imagine that would tie into Facebook?

Maybe this https://en.wikipedia.org/wiki/Facebook_Aquila

That guy is now working at Boeing, wow. Such a cultural difference. Hope he completely transforms Boeing's software division.

In Mars? Nothing that I know... :P

The CRS-10 that fly to the ISS seem to use RadHArd Cortex M4 or M0, according to this ARM PR document:

https://www.arm.com/blogs/blueprint/arm-rad-hard-chips-space

https://www.voragotech.com/products-main

Not to discount the question, because it's still interesting, but most of SpaceX's hardware doesn't leave the ionosphere.

But those that do leave, may even have a steering wheel.

Yes, a better question would be "What does Astroboic, Blue Origin, Firefly Aerospace, Ceres Robotics, Draper, Masten, Sierra Navada, Northrup Grumman, Lockheed Martin use"? Those providers will be on / near the moon shortly. So will SpaceX, but for rover, lander, station, orbiters, you'll get a better answer. (Longer duration, more strict payload budgets, extreme thermal concerns).

You can start poking around here: https://www.nasa.gov/content/commercial-lunar-payload-servic...

There's actually quite a few options in the "next gen" space, as many observed the need for updated compute. The one I've been closest to is HPSC: https://www.nasa.gov/directorates/spacetech/game_changing_de...

IIRC they use x86, just doubled just like their tesla brains.

SpaceX has not sent a rocket beyond the protective field of the earth so apparently the requirements are less stringent.

The Deep Space Climate Observatory was taken to L1 by a Falcon 9.

But far up did the Falcon 9 rockets go before the observatory separated?

The 2nd stage of the Falcon 9 separated from DISCOVR while it was still within a few hundred miles of Earth, and months before it got to L1

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