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Electronics => Electronics => Topic started by: WhomBom on December 07, 2010, 03:05:22 PM

Title: fast accelerometer
Post by: WhomBom on December 07, 2010, 03:05:22 PM
Hi guys, i'm looking for a bit of an extreme accelerometer; it should be able to measure up to 500g ideally, 250g at least.
It's sample frequency would be 48kHz ideally, but at least 10kHz.

Does anyone have an idea where i can buy a sensor that would meet my requirements? anything close to them would be ok as well  ;)
Title: Re: fast accelerometer
Post by: Joker94 on December 07, 2010, 06:31:28 PM
Just out of curiosity and for a better understanding what will this sensor be used for(application) I assume you mean 500 grams and not 500G's?

If that is the case most accelerometers will do the job. it is just a matter of how many axis of measurment you want.1,2 or 3.

http://www.sparkfun.com/categories/80 (http://www.sparkfun.com/categories/80)

Commonly most accelerometers at that level are about 2-3 G, if you expect to pull more G's than that you will have to look into some diiferent accelerometers.
Title: Re: fast accelerometer
Post by: waltr on December 07, 2010, 10:34:25 PM
There are Piezo sensors that are used to measure the G's at high frequency during vibration testing.
Many sources from googling "Piezo vibration sensors".
Title: Re: fast accelerometer
Post by: WhomBom on December 08, 2010, 04:13:40 AM
Hi guys, @joker: no, i mean G's  ;D

application for this is to measure the recoil of a large caliber rifle, that's why i need the range and crazy sampling frequency.

Sparkfun has a single axis 250G sensor but it's sampling rate is at 300Hz or something... the recoil  only lasts for a ms or so hence i'd probably completely miss it at 300Hz.

Tri-axis would be perfect, but i'm afraid high sampling frequencies and lots of data (3 directions instead of 1) aren't going to be friends. Nor do i expect 3 axis to be friendly on my wallet  ::)

@waltr, i found this; http://www.vibrametrics.com/downloads/Individual%20Spec%20Sheets/Model%201000%20Series.pdf (http://www.vibrametrics.com/downloads/Individual%20Spec%20Sheets/Model%201000%20Series.pdf)

it says it has a broad frequency range, does this also mean it outputs it's data at said frequencies? e.g. I don't want it to measure a 20kHz vibration and the transmit the data that it is sensing a 20kHz vibration at 500Hz, i want the actual G's!
Title: Re: fast accelerometer
Post by: waltr on December 08, 2010, 09:28:07 AM
WhomBom
 That sensor you linked to has an analog voltage output (see first line of data sheet where it says 10mV/g). This is purely a voltage verse time domain. This could be connected to an O'scope or to a high speed ADC.