Re: Accelerometers for >1000g measurements

On 2024-09-05 11:35, Arie de Muijnck wrote:

On 2024-09-05 00:30, Phil Hobbs wrote:

So for this customer gig I need to measure the actual acceleration of a parallel-rod transmission line that's being pounded into the ground with a built-in slide hammer.  (It's for measuring soil moisture and salinity by TDR.)
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We're thinking about putting the TDR pulser and sampler in the part that gets pounded (in a potted module obviously), so knowing how bad the acceleration gets is going to be important.  I expect that it'll be several hundred g in volcanic soil, so a full-scale range of 1000-2000 g would be about right.
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None of the MEMS IC accelerometers go anywhere near that high. Measurement Specialties makes them, but they're $160 in onesies, e.g.
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<https://www.digikey.com/en/products/detail/te-connectivity-measurement-specialties/830M1-2000/14118098> >
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Anybody used them?

 I've measured big fast forces using strain gauges.
If you can be sure the place where you place that on the metal rod stays elastic during the acceleration the bandwidth should not be a problem.
Now, computing a calibration and amplifying that signal is the next problem...

Thanks.  The issue there would be calibration, as you say, as well as the fact that it would measure the stretch at the surface and not the actual acceleration.
The objects in question don't have simple shapes, so going from the one to the other is a bit of a science project in itself.
If I can buy one with a cal sheet, that'll save me a lot of time.
Glen's other lead, Kunstler, advertises the model 8742A-50, also +-50k gees.  I have a quote request out to them too.
Next question is how to make SMT PCB survive a million cycles of that. Those fuze guys had it easy. ;)
Cheers
Phil Hobbs
--
Dr Philip C D Hobbs
Principal Consultant
ElectroOptical Innovations LLC / Hobbs ElectroOptics
Optics, Electro-optics, Photonics, Analog Electronics
Briarcliff Manor NY 10510
http://electrooptical.net
http://hobbs-eo.com