I would like to ask what MEMS digital accelerometer best suits for my project?

[Chris Emilson Hernaez]

Posted on January 30, 2018 at 14:49

Good day everyone, I am currently a student having a design project as our last requirement before graduation. As for our project. We are to develop a high sensitive sensor node that will be used for vibration monitoring of structural buildings. I am looking for a digital accelerometer that is capable of detecting ambient response civil structures and of that has a great range of sensitivity, low noise, low powered, and capable of having a freq. response of 0 Hz.   

All replies will be much appreciated. Thank you so much.

Posted on February 04, 2018 at 16:41

Hello,

as the question seems to be unanswered for a few days, here are some tips. I have to admit that I have no idea, what are seismic sensors made from.

Regarding the usage of the accelerometer. I would try to look for a low-g accelerometer: 

http://www.st.com/en/mems-and-sensors/accelerometers.html?querycriteria=productId=SC444

 , probably LIS3DH or LIS3DL and look into the datasheet for the lowest range and resolution per LSB. Do you have an idea, how big is the acceleration (and what is the frequency) of structural vibrations in a building? Try to compare it to the LSB resolution in the datasheet and guaranteed accuracy. It might be possible that you will only get some noise.

There are also PVDF sensors (here is a blog post that might provide some inspiration:

https://www.element14.com/community/groups/internet-of-things/blog/2014/04/13/impact-vibration-and-ultrasound-sensing-with-pvdf-piezo-sensors

 ) that have a piezo effect (similar type as found in birthday cards) and could provide a meaningful signal after amplification.

David