Suitable acceleration sensor for vibration measurements (EVAL-ADXL1003Z)

Hi Josh (gruessegemuese ) let's go by parts;

" As far as I understand, the "Bandwidth" is the max. possibly detected acceleration frequency. Is that correct?"  - yes! In fact once you cross the cutoff frequency the sensor will keep working (the scale factor would remain the same by example) but will pull out an attenuated version of the signal.

Expecting that the arduino's sampling rate is around 9.8 KHz (Arduino ADC: Everything you Must Know about the Built-In ADC), it should be able to hold your 2.5 KHz BW. However, if you want to squeeze the maximum performance out of the sensor, you may need an external ADC with a higher BW to further mitigate aliasing without using a filter from higher order. -An application example for 5KHz BW can be found in the interfacing analog output below 10khz section, page 11 from the ADXL1003 datasheet.

That being said, you should be fine if you want to detect shocks. The 10 bits and the bandwidth is just enough.

On the eval board side be you can find all the documentation here. Remember that the 1003 evalboard already presents a 15 KHz LP filter.

As for sensor alternatives, it all depends on your specific application. Why do you need an analog sensor? Does the budget limit us to the arduino's ADC? Digital output parts like ADXL382 and ADXL371 may fit your context just by looking at the measurement range and BW.

ADXL371/2 is a digital output part that fits your needs in terms of measurement range and BW, it also can be used with this plug and play Arduino shield.

(ADXL382 could be a nice option with a complete ready to use evaluation board alongisde with custom software with all you could need for testing in case you end not needing the 200g range)

Hope this helps.

Mario SM

Hi Mario SM,

Thank you very much for your Help! I'm Using and Arduino Uno R4 wifi with a 14bit ADC. Regarding to this post it should be 1MHz for the RA4M1 chip. So that would be suitable for me right? The data sheet of the RA4M1 is a little bit too much for me to understand how to get to such a value. On page 88 and 89 is something about the Conversion time of the adc.

MarioSM said:

On the eval board side be you can find all the documentation here. Remember that the 1003 evalboard already presents a 15 KHz LP filter.

I saw that, that would be totally fine!

MarioSM said:

As for sensor alternatives, it all depends on your specific application. Why do you need an analog sensor? Does the budget limit us to the arduino's ADC? Digital output parts like ADXL382 and ADXL371 may fit your context just by looking at the measurement range and BW.

To be honest i wanted to stick to a analog sensor because there I could easaly could keep track of my filtering and the recording frequency of the data. Because according to some of my lectureres that can be a bit difficult sometime with digital ones and I thought it was simpler :D. But maybe they also just said that because we were only using arduinos in our class. And as I have to pay for most of my  material for my thesis by myself I thought to stick to something cheap that I have and already know a bit.

MarioSM said:

(ADXL382 could be a nice option with a complete ready to use evaluation board alongisde with custom software with all you could need for testing in case you end not needing the 200g range)

I' not 100% sure if i need the +- 200g. But as I also want to investigate in impact on the wheel I want to be on the safe side. And my resolution is still good enough with that range.

Again Than you very much!

Kind Regards Josh

Hello again Josh, glad I could help.

That Arduino will make the work just fine in this case. I totally feel you, I had the same experience on my thesis work not long time ago. In any case before ordering anything try to research about the available libraries and modules in our wiki and main page for the previouslhy mentioned parts. It may happen that the ADXL37x has enough documentation/software released to make your work even easier besides your previous experience.

In any case do not doubt to reach us again in the future if you need any kind of help!

Mario SM