Building your own shaker table is a heck of a rabbit hole. Unless you know
your environment I don't think it is worth doing any sort of vibe testing
or trying to make your own shaker table.
If you are just looking to determine the general robustness of electronics
I think the best option is to perform some shock 'testing' by dropping it
off of tables. This is only useful by way of comparison, of course, unless
you know what the shock loads will be in flight.
Especially for the little boards most of you are working with, any damage
to them will any higher frequencies anyway. In case anyone is not familiar
with vibration analysis, an ideal shock is a sum of all frequencies applied
so their waveform produces a big spike at that moment.
Thanks,
Lars Osborne
On Mon, Dec 21, 2015 at 7:43 PM, Monroe L. King Jr. <
monroe@xxxxxxxxxxxxxxxxxx> wrote:
Hey that's cool! I guess I can get a big sub and try that out.
-------- Original Message --------the
Subject: [AR] Re: Flight Computer
From: Ben Brockert <wikkit@xxxxxxxxx>
Date: Mon, December 21, 2015 8:26 pm
To: "arocket@xxxxxxxxxxxxx" <arocket@xxxxxxxxxxxxx>
Professional shaker tables are still just big speaker cores. I visited
one they use to test hardware in the mobile launch platforms at KSC, andsine
it's 'just' a 480kW amp and a fat coil of wire. You can build a
surprisingly realistic approximation with a subwoofer, amplifier, and
wave generator.looking
If NASA was cool they'd build a speaker cone for their rig and recreate
that scene from Back to the Future.
Things that flew without going through random vibe testing: all of
Armadillo and Masten's rockets. Though perhaps Armadillo could have found
that their GPS was sensitive to vibration if it had been tested before
flight.
On Monday, December 21, 2015, Robert Watzlavick <rocket@xxxxxxxxxxxxxx>
wrote:
That's weird - I would think any reasonable PCB would stand up to
vibration the same as any other. However, I have a BBB and just
vibrationat it, I would suspect the power and/or USB connections as potential
failure points. In a previous life, we had to delete the planned
knowspecs for a product the USB connector failed vibration tests. Good to
thought Ithough - thanks for the tip.
I was trying to figure out the best way to check out my flight computer
setup for vibration. I don't have access to a shaker table so I
fewwould strap it to my truck bumper and drive it around for a while. A
leastmiles over our pothole-laden roads should be a pretty good test, at
site.for random excitation.
-Bob
On 12/21/2015 04:25 PM, doug knight wrote:
Not robust. Mount was good but jostling around the device had it run
intermittently. Worked well on benchtop but not repeatable at launch
ArduinosAnd did not work at all in launches. Scraped and went to arduino and
problems disappeared. This was a couple years ago also. Of course
more ahave other limitations so
Doug Knight.
On Dec 21, 2015 3:25 PM, "Robert Watzlavick" <rocket@xxxxxxxxxxxxxx
<javascript:_e(%7B%7D,'cvml','rocket@xxxxxxxxxxxxxx');>> wrote:
What kind of problems did you run into? I considered the BeagleBone
Black with FreeRTOS but ended up going with the Netburner MOD54415.
Monroe - I glanced over the OSAL stuff a while back and it looked very
sophisticated but I don't think it's a turnkey system. I think it's
etc.). Ifset of middleware building blocks (messaging stack, file system,
you have the time to invest in it, it would be interesting to see how
useful it turns out to be.
-Bob
On 12/21/2015 01:13 PM, doug knight wrote:
Monroe
I did not haveagood experience with beaglebones and hobby high power
rockets. They did not seem very robustly all. Of course YMMV.
Doug Knight