[PaulKeeble]

The physical interface itself is going to be a big deal, people are going to be just swapping cards constantly and you'll need multiple people just doing this. Status of read is a big part of this as well so some amount of custom LEDs and such for status of ingress will be required. What a horrible job being in a room with 100s of thousands of SD cards just feeding them into slots and then into an empty bin!

Its possible from a PCI-E bandwidth point of view but its going to require some seriously specialist USB interfaces. I am tempted by the same solution others suggest, smaller amounts per machine less expensive and extreme solutions into normal switches and then out across fibre.

What a crazy thing to be doing, the mad situations companies get themselves into when they should just have networked cameras and VPNs or at the very least distributed ingress machines!

[Terr_]

Perhaps some kind of "SD-card multiplexer" arduino project, where you have 50 SD breakout boards all mounted in a tall stack, each with an LED, and maybe a "reset" button if it doesn't detect ejections. Some circuitry in the middle would set each LED status color, and switch which of the 50 is currently connected to a single set of access pins.

It still involves annoying work by humans, but it would be much more straightforward: See a bay that is showing the "idle" color, remove any finished card and put it in the finished-box, grab a card from the to-do box and put it in, then press the button to signal a new card is waiting.

If that process took 6 seconds, 1000 cards would mean 100 minutes of tedious work, but you can spread it over multiple people or (since the card-read takes time) do it in short bursts interspersed with other activities.

[tetha]

In most cases I've seen scales similar to this - body cams in security, scanners at postal services and such, the physical part is offloaded to the individuals working with the thing: at the end of the day, you put your thing into a charger, or into a box and connect it up or something like that.

So from there, my thought is indeed: Why shouldn't we get 1000 micro sd card readers (or multi readers), attach those to a bunch of PIs streaming the cards to a central server, have people put their SD card in there at the end of a day? After that, you can kick off the reads in a batch, re-seat the cards that aren't set correctly and that's it.

One could reduce hardware cost by having some LED turn on or off if a card in a reader can be swapped, but with a thousand people doing this, complicated instructions tend to be a bad thing. Unless the transfer is fast enough to wait for it.

But it's always fun how complicated some of these physical problems become if you scale them up. Like, consider how many storm drains are out there in a city. If each needs to be touched once every 3 years... suddenly you've created a dozen jobs.

[snypher]

Would be a straightforward job for a pick and place style robot, if you had cycle time to budget for it.