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RPIs are increasingly hard to get or too pricey. What gives? Is it the supply chain issue?
Yeah, same as everything else.
Other boards are easier to find. As an example, over 18000 Beagleboards should arrive at Mouser by the next months, of which over 2500 are expected by tomorrow. TME.eu also have some ARM boards in stock, etc.
Given that pi design files are open, they could presumably build their own. They would probably do this anyway.
The newer Pi versions use SoCs that are only made for the Pi, you can't just go and buy them. (And even for the ones where it was a "normal" part, it's still Broadcom, they're not exactly freely selling parts)
The datasheet suggests that it's a real CM4 inside the box.
No pictures?
According to this page the 40 pin IO is available through a MIL-DTL-38999 connector. I've always liked those military connectors. https://en.wikipedia.org/wiki/U.S._Military_connector_specif...
The connectors alone cost more than the Pi hardware.
True only for the hobbyist editions of the Pi.
They are literally using Pi 4 compute modules with wireless, 8GB RAM, and 32GB flash which costs less than 35€
This may seem somewhat silly to most people but if it isn't vaporware and can actually meet demand and fulfill procurement needs, could be a solid choice. Choosing and sourcing SBC's for hardware is an absolute nightmare these days because of the thousands of options, horrible supply chains, and essentially nonexistent documentation or BSP's for the vast majority of them.

Raspberry Pi's are undeniably the easiest SBC to work with, and for a huge portion of industrial, defense, and aerospace products and devices are a near ideal choice except for their "hobbyist" level attributes.

A robust Pi4 clone that supports nvme drives, has no Bluetooth or Wifi by default, and has something like ISO9001 certification to check the boxes for big enterprise contracts would sell like hotcakes. It's somewhat surprising to me that the Pi foundation hasn't made something to this tune yet (the Pi CM4 may as well be vaporware - they're basically impossible to find anywhere even in single-digit quantities).

> the Pi CM4 may as well be vaporware - they're basically impossible to find anywhere even in single-digit quantities

That's near as damnit true for _all_ Raspberry Pi products right now. You can pretty much only buy any of them in single unit quantities, and it's like buying concert tickets, you need to keep your eyes open to find out exactly when someone has some for sale, and you need to jump on them before they sell out.

https://rpilocator.com

I managed to snag a Pi Zero 2 W a week or so back, had to get it shipped from Spain to Sydney which cost more than the Pi. I was limited to a single one at checkout.

Nice, it is currently available at the tiendatec.es shop, I managed to buy one. Shipping inside EU does indeed cost more than the board.
> supports nvme drives

Before that, I'd honestly like to see TPM 2.0 support baked in first.

> has no Bluetooth or Wifi by default

Alas, not the case here[1]. Genuinely looks like they just stuffed a consumer RPi CM4 on a custom carrier board wrapped in metal, pushed through the easier boilerplate environmental checks like all their other SBCs, then put out a press release.

Not sure how I feel about the interconnect choice; power via Omnetics proprietary (28 VDC input, but nothing assertive in datasheet on satisfying 704 requirements) and everything else via Glenair proprietary (with roughly half a quarter physical clearance between them) in what appears to be the equivalent of 38999 service class F finish (which won't survive 500-hr dynamic salt spray). I also do wonder if mechanical engineers would raise a nit at the countersunk retaining of enclosure top.

The hardest thing to swallow here is having to pay an undisclosed MIL premium for what will fundamentally be constrained by its consumer RPi CM4 core. Even if Curtiss-Wright lifetime buys for a gratuitous 10-yr support posture, it's hard to imagine how liabilities like tin whiskers can be pragmatically avoided, or what that means in terms of MTBF post-fielding.

This will probably fill someone's niche, but I agree that what's really missing is a robust RPi4 clone.

[1] https://www.curtisswrightds.com/products/computing/systems/s...

> Before that, I'd honestly like to see TPM 2.0 support baked in first.

Maybe they could keep the price down by having a TPM connector and add the pinout for it, or even reuse some of the GPIO pins for it?

You can mitigate tin whiskers with a conformal coat application. It's not going to be as good as lead solder but it is an acceptable method when you have no other option.

Another possibility is that these are modified CM4 boards where parts were removed and resoldered using lead solder. The Broadcom chip is really the most critical component as you cannot buy them off the shelf but everything else could be purchased new and installed onto a stripped board or a brand new one made using the CM4 design files using lead solder.

> You can mitigate tin whiskers with a conformal coat application.

Precisely how effective do you think that'll be when your core packages are fine grid BGA?

> Another possibility is that these are modified CM4 boards where parts were removed and resoldered using lead solder.

This is the only long-term and standard solution I see, including package reballing. However, the fundamental problem with this approach is that the underlying PCB substrate is consumer grade that isn't designed for rework.

For me it is a joke, because the RPi has a long history of being an unreliable plateform.

Exemple: powercut and memory cards corruptions, etc...

So, if I had to design for military specs, I would probably bet on some other more robust platform.

SD cards do seem to die very easily, from what I hear USB sticks are much more reliable.
From what I understood, it was not necessarily the quality of the SD card the problem, but that the rpi was lacking a capacitor or something like that preventing the current to be shut instantly when there is a power cut or a shutdown.

And sdcard don't like at all sudden loss of power in the middle of a 'write' or 'refresh' command.

Cards death or corruption happened to me a lot even when taking care with rpi but never when using beaglebones.

MicroSD cards are IMO a poor choice to store the OS, using a USB thumbdrive or a USB enclosure is IMO more robust but not as compact.

Thankfully you can boot from those on the Pi.

I couldn't find any reference to storage options on the product page. The compute module is available with 0-32GB onboard eMMC but it's possible they're using an alternate storage solution on the carrier board. Hopefully they're using something more reliable than sd.
Would probably also need good performance on 128bit floats as well as ECC memory
I'm curious where 128bit floats become a significant concern? My understanding is that any critical numerical things would be done using integer arithmetic to eliminate any imprecision errors, and anything else likely is fine using doubles.
Integers are not often expressive enough for a lot of applications, so we use floats. I'm sure for a lot of things, doubles are good enough, but a better safe than sorry approach will lead you to use 128bit floats.

The case study that I learned in my Numerical Analysis course was the patriot missile incident, which lead to 28 death in the early 90s. Essentially, there was a timer implemented that used floats, and due to the inherent rounding error of floats, after enough iterations this caused the missile to miss its target by miles. There were some operational errors involved, such as leaving the missile "turned on" for longer than was suggested by the manufacturer, but still, these types of incidents should not happen.

Even with double precision, there are errors. For instance, 0.3 is actually represented as:

0.299999999999999988897769753748434595763683319091796875

How do you design for and validate "rugged"-ness? Are there standardized tests?
The US military has standards, though I don't know which, if any does this product try to meet/comply with:

MIL-STD-167: is a test method standard for mechanical vibration of shipboard equipment

MIL-S-901D: is a Navy test specification for shock to simulate explosions in the water next to a ship or submarine.

For the curious, you can grab PDFs at: https://cp-techusa.com/knowledge-zone/military-specification...

One of the few applications you can still use leaded solder, as it's less brittle.

Even though the board can be hardened, and temperature ranges of the Broadcom seem acceptable, what bothers me is that the Broadcom still boots via unauditable "mystery" code in the GPU. Am still correct, or has that changed?

Yes, many of them. "Rugged" is of course just a word to brag about, they will actually claim "meets MIL-STD-{xxxx}" and that standard will include things like manufacturing, materials, and test procedures.

For example, operating in a temperature controlled environment at various extremes, being put on a precisely controlled vibration device for a certain amount of time, being exposed to RF or radiation, etc.

I wonder what the pi foundation's stance is on using their product geared towards teaching ( https://www.raspberrypi.org/about/ ) to create military applications.
Probably the same as their stance on using Pis for retro gaming, media players, and magic mirrors. Just because much of western academia has a deep hatred for all things military related doesn't mean that anything created for use in education is fundamentally at odds with use in the military. As shocking as it might seem, the military actually does a lot of teaching.
Technical advancement in civilian space is surpassing military, so military worldwide has no choice but to adopt civilian offerings in 21st century.

The argument that civilian technologies shouldn’t be used to accelerate military development assumes military is way ahead. This is no longer the case and a new thinking is needed.

(OT & mini Ask HN: I was told this from a right-leaning friend, who I suspect was just replaying a lecture or an essay. And basically I am too, shamefully. Have anyone heard a similar blurb somewhere?)

are they just putting a Pi in a Mil spec case? where are they getting the mil spec chips from?
They're almost certainly putting a standard spec pi into a mil spec case. They might do some torture tests to weed out the bad ones / "uprate" the components.

The Broadcom BCM2711 is already rated -40 to +85C which is considered industrial or rugged. I have no idea what the rest of the components on the Pi board are rated for though.

The CM4 is technically rated -20 to +85C on the datasheet: https://datasheets.raspberrypi.org/cm4/cm4-datasheet.pdf
Good point. Chip specs don't always represent hard operating limits, they are just the limits to what the manufacturer has tested to. Either the mfg has done some additional testing that the chip can work down to -40C or they've done something like else (like add a heater... not unusual for rugged machines).
Can we have the important part of "Mission Computer" in the title as well?
I love it when the term "military standard" or "military spec" gets thrown around.

If you want a company with a long history of making industrial computers then Onlogic[1] just released a raspberry pi box.

Onlogic used to be called logicsupply and they've made industrial and fanless computers for rough operating environments for many years.

1. https://www.onlogic.com/industrial-raspberry-pi/

Curtiss-Wright is a legit defense aerospace company though…
oic, I had no idea what it was. Thought it was some guy named Curtis and his blog tbh.
They built a box to put a raspberry pi compute module in that meets certain standards, this isn't some shitty amazon product putting that label on but an actual product targeted towards the defense market.
The case may be rugged, but the connectors/sockets are still a weak spot.
Heh, these aren't just hot terms that are willy-nilly thrown around like "cloud" or "serverless".

> The unit meets stringent MIL-STD / DO-160 environmental standards (MIL-STD-704F, MIL-STD-1275D, MIL-STD-461F, and RTCA/DO-160 for civil and military use)

These are legitimate standards that have strict specifications.

Curtiss-Wright isn't just some random nobody in the industry.

They literally make black boxes (crash recorders) for planes, for example.

Wouldn't be surprised if more of these end up in industrial civilian use than in actual military use.
An idea: RC sized electric car that can deliver a tank mine under the tread of a tank.

implementation: Using cheap, off the shelf parts: raspberry Pi (such as this one in the post), camera, GPS...

It allows operator to choose a tank target and then this bot self-drives in front of a track.

The only way a tank mine can detonate is if a tank rolls over it. So as long as you are not a tank.. this little bot would be pretty safe.

Would possibly be a game changer for the ukraine war if these could be made en masse cheaply.

Hard to see how that tactically beats a Javelin or other anti-tank missile, which are clearly affordable enough.
And Javelins don't get stuck in dirt, wallowed in ditches or stymied by curbs.
It may not beat Stugna-P but it should beat Javelin when it comes to not exposing yourself. Also I imagine that such a vehicle could perhaps carry other payloads, too.
Having worked with CW products before, I imagine this will be in the $500-$1k+ price range and won’t satisfy many aerospace needs/constrains.

There’s plenty of “oh we’re not using a raspberry pi, that’s a kids toy” in the industry, so I’m finding it difficult to find the niche this product satisfies, when there are plenty of more powerful/established options.

As someone deeply interested in this subject, would you mind pointing out what options there are for products that would fit this criteria of being a SBC made with aerospace constrain in mind?