To see the violence that a cubesat has to go through, here is a test we did today on a power supply board.
http://aprs.org/psat/Vibe-coil-test1724.MOV (1 meg file)
It failed even before we got to the 22G requirement!
Yes, it is rocket science… a nasty place to ride…
Bob, WB4aPR
On 10/16/14, Robert Bruninga bruninga@usna.edu wrote:
To see the violence that a cubesat has to go through, here is a test we did today on a power supply board.
http://aprs.org/psat/Vibe-coil-test1724.MOV (1 meg file)
It failed even before we got to the 22G requirement!
Yes, it is rocket science… a nasty place to ride…
<snip>
The video clip reminded me of something in the episode "Spider" of the HBO series "From The Earth To The Moon". The narrator described what happened in the Apollo Lunar Module during the launch like being inside a can of paint while it's mixed in the store.
73s
Bernhard VA6BMJ @ DO33FL
No conformal coating? hv
-----Original Message----- From: amsat-bb-bounces@amsat.org [mailto:amsat-bb-bounces@amsat.org] On Behalf Of Robert Bruninga Sent: Wednesday, October 15, 2014 7:18 PM To: amsat-bb@amsat.org Subject: [amsat-bb] Cubesat Vibration Test
To see the violence that a cubesat has to go through, here is a test we did today on a power supply board.
http://aprs.org/psat/Vibe-coil-test1724.MOV (1 meg file)
It failed even before we got to the 22G requirement!
Yes, it is rocket science… a nasty place to ride…
Bob, WB4aPR _______________________________________________ Sent via AMSAT-BB@amsat.org. AMSAT-NA makes this open forum available to all interested persons worldwide without requiring membership. Opinions expressed are solely those of the author, and do not reflect the official views of AMSAT-NA. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
This is why you do the shake tests.
Two thoughts come to mind here...
building for 25 G vibration and 1000 G shock is pretty much consumer grade stuff and is easily achieved with off the shelf components.
The hard part comes in when you realize that riding on a solid rocket motor is brutal, and results in resonances that sweep through a wide range of frequencies during the burn. The vibration tables generally emulate this really well and weaknesses can be exposed in short order. If the circuit boards exhibit a resonance , components can literally be popped right off of the board... and sometimes weaknesses internal to the die bonding in some components can turn up as well.
If I had to rely on conformal coating to stake the parts for 22G, I'd be worried about the payload....
Glen AA8C
On 10/16/2014 01:01 PM, Harvey N. Vordenbaum wrote:
No conformal coating? hv
-----Original Message----- From: amsat-bb-bounces@amsat.org [mailto:amsat-bb-bounces@amsat.org] On Behalf Of Robert Bruninga Sent: Wednesday, October 15, 2014 7:18 PM To: amsat-bb@amsat.org Subject: [amsat-bb] Cubesat Vibration Test
To see the violence that a cubesat has to go through, here is a test we did today on a power supply board.
http://aprs.org/psat/Vibe-coil-test1724.MOV (1 meg file)
It failed even before we got to the 22G requirement!
Yes, it is rocket science… a nasty place to ride…
Bob, WB4aPR _______________________________________________ Sent via AMSAT-BB@amsat.org. AMSAT-NA makes this open forum available to all interested persons worldwide without requiring membership. Opinions expressed are solely those of the author, and do not reflect the official views of AMSAT-NA. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
Sent via AMSAT-BB@amsat.org. AMSAT-NA makes this open forum available to all interested persons worldwide without requiring membership. Opinions expressed are solely those of the author, and do not reflect the official views of AMSAT-NA. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
I don't have anything to add to the discussion, I just wanted to say I love threads like this and I'd like to see more. I'll never be a rocket scientist, but reading about all the design considerations, experiences, testing, trials and tribulations, and minutia involved in engineering and launching these things is cool.
73 Goody K3NG
On Thu, Oct 16, 2014 at 9:19 AM, Glen Gardner glen.gardner@verizon.net wrote:
This is why you do the shake tests.
Two thoughts come to mind here...
building for 25 G vibration and 1000 G shock is pretty much consumer grade stuff and is easily achieved with off the shelf components.
The hard part comes in when you realize that riding on a solid rocket motor is brutal, and results in resonances that sweep through a wide range of frequencies during the burn. The vibration tables generally emulate this really well and weaknesses can be exposed in short order. If the circuit boards exhibit a resonance , components can literally be popped right off of the board... and sometimes weaknesses internal to the die bonding in some components can turn up as well.
If I had to rely on conformal coating to stake the parts for 22G, I'd be worried about the payload....
Glen AA8C
On 10/16/2014 01:01 PM, Harvey N. Vordenbaum wrote:
No conformal coating? hv
-----Original Message----- From: amsat-bb-bounces@amsat.org [mailto:amsat-bb-bounces@amsat.org] On Behalf Of Robert Bruninga Sent: Wednesday, October 15, 2014 7:18 PM To: amsat-bb@amsat.org Subject: [amsat-bb] Cubesat Vibration Test
To see the violence that a cubesat has to go through, here is a test we did today on a power supply board.
http://aprs.org/psat/Vibe-coil-test1724.MOV (1 meg file)
It failed even before we got to the 22G requirement!
Yes, it is rocket science… a nasty place to ride…
Bob, WB4aPR _______________________________________________ Sent via AMSAT-BB@amsat.org. AMSAT-NA makes this open forum available to all interested persons worldwide without requiring membership. Opinions expressed are solely those of the author, and do not reflect the official views of AMSAT-NA. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
Sent via AMSAT-BB@amsat.org. AMSAT-NA makes this open forum available to all interested persons worldwide without requiring membership. Opinions expressed are solely those of the author, and do not reflect the official views of AMSAT-NA. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
Sent via AMSAT-BB@amsat.org. AMSAT-NA makes this open forum available to all interested persons worldwide without requiring membership. Opinions expressed are solely those of the author, and do not reflect the official views of AMSAT-NA. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
Built like a $30.00 Baofeng HT !!
K7TRK
-----Original Message----- From: amsat-bb-bounces@amsat.org [mailto:amsat-bb-bounces@amsat.org] On Behalf Of Robert Bruninga Sent: Wednesday, October 15, 2014 5:18 PM To: amsat-bb@amsat.org Subject: [amsat-bb] Cubesat Vibration Test
To see the violence that a cubesat has to go through, here is a test we did today on a power supply board.
http://aprs.org/psat/Vibe-coil-test1724.MOV (1 meg file)
It failed even before we got to the 22G requirement!
Yes, it is rocket science… a nasty place to ride…
Bob, WB4aPR _______________________________________________ Sent via AMSAT-BB@amsat.org. AMSAT-NA makes this open forum available to all interested persons worldwide without requiring membership. Opinions expressed are solely those of the author, and do not reflect the official views of AMSAT-NA. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
participants (6)
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B J -
Glen Gardner -
Goody K3NG -
Harvey N. Vordenbaum -
Robert Bruninga -
Ted