5 ms·

Military-Spec Raspberry Pi Mission Computer Revealed

17 points by intrasight 5y ago

mmastrac 5y ago
As a curiosity, how does the compute module's connectors handle serious vibration? I cannot imagine it was designed for major abuse.
- gruturo 5y ago
  > As a curiosity, how does the compute module's connectors handle serious vibration? I cannot imagine it was designed for major abuse. The compute module has 4 holes for bolts at its corners. If it's securely bolted to its board, with the correct spacers, I expect the contacts would experience no relative movement and be pretty good, at least until the vibrations are so severe that the bolts start to come off - but there are thread locker adhesives for those use cases. --Edit: This is of course for the Compute Module only. The board it's bolted onto should of course be designed according to the use case - I doubt the Curtiss-Wright milspec thing shown in the article uses anything like the official Raspberry Pi IO Board, or the many semi-nameless ones you find on Amazon. I also doubt MicroSD is an option, given that I've had a card fly out of its socket in one extreme case.
  - CWDS-tech 5y ago
    Yes, bolts help so that stress not on connector. That connector on CM4 is suitable for the shock and vibe environments. That connector family is TRL9. Low risk. Qual levels are stated on product sheet and webpage. Qual reports under NDA only to qualified customers. Having said that, enjoy reading MIL-STD-810 and what the tests mean. Carrier board custom for product, but standard design approach. Entire design approach and some subassemblies and parts of it are TRL9. CM4108032 does not have the SD option (no lines active on the CM4 board to board). Only CM4lite does that. Increased storage is via add on miniPCIe in expansion ring. This is TRL9. MicroSD is TRL7 but not a great trade-off due to many issues and risk. Not supported.
fsagx 5y ago
product page: https://www.curtisswrightds.com/products/computing/systems/sff/duracor-pi.html https://www.curtisswrightds.com/products/computing/systems/s...
- BLO716 5y ago
  Ya broke on the main site links. Thanks for sharing.
fsagx 5y ago
I won't believe it's real until I see one on Jeff Geerlings youtube channel.
- CWDS-tech 5y ago
  If someone has contact with Jeff (not just a cold reach out), let him know to put in inquiry, and reference "EAU for review"
Nextgrid 5y ago
I'm curious as to how they manage interference and shielding when running and GPIO and PCIe through these connectors.
- CWDS-tech 5y ago
  PCIe does not come out of box. See block diagram. Stays inside for expansion ring connection. This is TRL9 design approach. HAT signals, GbE, USB, HDMI, etc that come out are all appropriately protected or conditioned to meet EMI requirements per product spec. All of this is TRL9.
  - O5vYtytb 5y ago
    Can you share the datasheet/block diagram without requiring us to create an account?
CWDS-tech 5y ago
I will come back and answer questions - to a point- on this. I'm the one making this happen at CW.
bullen 5y ago
Cooling has to be tied to the mass, and without pictures of that you cannot sell this thing. Here is the best way I found to solve passive cooling with mechanical protection for civilian use: http://move.rupy.se/file/pi_4.jpg http://move.rupy.se/file/pi_4.jpg

17 points by intrasight 5y ago

As a curiosity, how does the compute module's connectors handle serious vibration? I cannot imagine it was designed for major abuse.

gruturo 5y ago
> As a curiosity, how does the compute module's connectors handle serious vibration? I cannot imagine it was designed for major abuse. The compute module has 4 holes for bolts at its corners. If it's securely bolted to its board, with the correct spacers, I expect the contacts would experience no relative movement and be pretty good, at least until the vibrations are so severe that the bolts start to come off - but there are thread locker adhesives for those use cases. --Edit: This is of course for the Compute Module only. The board it's bolted onto should of course be designed according to the use case - I doubt the Curtiss-Wright milspec thing shown in the article uses anything like the official Raspberry Pi IO Board, or the many semi-nameless ones you find on Amazon. I also doubt MicroSD is an option, given that I've had a card fly out of its socket in one extreme case.
- CWDS-tech 5y ago
  Yes, bolts help so that stress not on connector. That connector on CM4 is suitable for the shock and vibe environments. That connector family is TRL9. Low risk. Qual levels are stated on product sheet and webpage. Qual reports under NDA only to qualified customers. Having said that, enjoy reading MIL-STD-810 and what the tests mean. Carrier board custom for product, but standard design approach. Entire design approach and some subassemblies and parts of it are TRL9. CM4108032 does not have the SD option (no lines active on the CM4 board to board). Only CM4lite does that. Increased storage is via add on miniPCIe in expansion ring. This is TRL9. MicroSD is TRL7 but not a great trade-off due to many issues and risk. Not supported.

fsagx 5y ago

product page: https://www.curtisswrightds.com/products/computing/systems/sff/duracor-pi.html https://www.curtisswrightds.com/products/computing/systems/s...

BLO716 5y ago
Ya broke on the main site links. Thanks for sharing.

fsagx 5y ago

I won't believe it's real until I see one on Jeff Geerlings youtube channel.

CWDS-tech 5y ago
If someone has contact with Jeff (not just a cold reach out), let him know to put in inquiry, and reference "EAU for review"

Nextgrid 5y ago

I'm curious as to how they manage interference and shielding when running and GPIO and PCIe through these connectors.

CWDS-tech 5y ago
PCIe does not come out of box. See block diagram. Stays inside for expansion ring connection. This is TRL9 design approach. HAT signals, GbE, USB, HDMI, etc that come out are all appropriately protected or conditioned to meet EMI requirements per product spec. All of this is TRL9.
- O5vYtytb 5y ago
  Can you share the datasheet/block diagram without requiring us to create an account?

CWDS-tech 5y ago

I will come back and answer questions - to a point- on this. I'm the one making this happen at CW.

bullen 5y ago

Cooling has to be tied to the mass, and without pictures of that you cannot sell this thing. Here is the best way I found to solve passive cooling with mechanical protection for civilian use: http://move.rupy.se/file/pi_4.jpg http://move.rupy.se/file/pi_4.jpg