LPS25HB for force readings

Dario Bortolotti · ‎2018-02-02

Posted on February 02, 2018 at 12:08

Dear all,

I am inquiring the possibility to use LPS25HB absolute pressure sensors as force sensors. My idea is to integrate the sensors into a rubber or silicon layer (5 - 10 mm thick) so that the rubber layer, acting as transducer, compresses the sensor's chamber. Would this compromise the sensors' functioning? Do you have any suggestions? Thank you in advance for you kindness!

Best regards,

Dario

#lps25hb-pressure-force

Legacy member · ‎2018-02-04

Posted on February 04, 2018 at 16:31

Hello,

If you are trying to measure weight, I would consider using a load cell:

https://learn.sparkfun.com/tutorials/getting-started-with-load-cells

LPS25HB is constructed as an air pressure sensor and has a delicate membrane inside, so I wouldn't recommend putting it into any other material. However, you can try to embed the sensor into some kind of an air pillow or box and measure the air pressure change after applying pressure to the box. However, this is sensitive not only to applied force, but also to temperature changes. In addition to that, you need to be careful to not break the sensor's membrane, it is very easy to get outside the pressure boundaries. (You can try this if you put the sensor in a well sealed lunch box and applying pressure on the box, or changing the temperature of the environment.)

David

Legacy member · ‎2018-02-05

Posted on February 05, 2018 at 10:10

I just remembered an older question where I provided an estimate to get the idea of how much pressure can be generated by stepping on a sealed box with a pressure sensor inside:

https://community.st.com/0D50X00009XkY8gSAF

Dario Bortolotti · ‎2018-02-05

Posted on February 05, 2018 at 10:15

,

Dear David,

Thank you for your reply. I was wondering if, sealing the whole sensor into the polymer, its own sensing chamber could act as the sealed box you mentioned.

Il 05 feb 2018 10:10 AM, David Koudela <,st-microelectronics@jiveon.com>, ha scritto:

STMicroelectronics Community <,https://community.st.com/?et=watches.email.thread>,

Re: LPS25HB for force readings

reply from David Koudela<,https://community.st.com/0D70X000006SiuWSAS