Actions
Forum Thread Details
  • Replies 4 replies
  • Subscribers 338 subscribers
  • Views 2041 views
  • Users 0 members are here
Related

Piezo film sensor for footstep detection

will_hs

I’m currently looking into detecting footsteps on a wooden floor using piezoelectric sensors and recording the output as audio.

 

After some research it seemed like a cantilever piezo film sensor might be suitable. I have ordered a few of these (MiniSense 100, LDTM-028K).

I’m wondering if there is a optimal way to mount these sensors to maximise vibrational transfer. At the moment I have soldered the sensor to a small PCB and have the PCB attached to the floor with adhesive tape. I’m amplifying the signal with a jfet preamp. I’m finding that footsteps around 6” from the sensor are barely registering above the noise floor.

 

Any advice on mounting these sensors, or even suggestions for other sensors that might be more suitable, would be much appreciated!

Thanks

Parents

  • Does the solution have to incorporate a piezoelectric sensor? What made you choose this?

     

    The key, in my opinion, is to consider wave propagation and what could cause this wave to distort or dampen to the point that it becomes unrecognisable (as per your example). This should then help you choose a sensor and a location.

     

    I would have thought a sensor, like a tiny Electret microphone, mounted on a wall above the wooden floor might be better for this application as this would be able to detect the wave propagating from floor boards when there are footsteps and it's unlikely to become distorted (maybe lots of echo could cause problems but this would need testing). A piezo attached to a floor board might not always work as a wave travelling through a long floor wood, could dampen or distort quite quickly due to it's organic properties especially if that footstep sound has to also "hop" across to the next floor board etc.

Reply

  • Does the solution have to incorporate a piezoelectric sensor? What made you choose this?

     

    The key, in my opinion, is to consider wave propagation and what could cause this wave to distort or dampen to the point that it becomes unrecognisable (as per your example). This should then help you choose a sensor and a location.

     

    I would have thought a sensor, like a tiny Electret microphone, mounted on a wall above the wooden floor might be better for this application as this would be able to detect the wave propagating from floor boards when there are footsteps and it's unlikely to become distorted (maybe lots of echo could cause problems but this would need testing). A piezo attached to a floor board might not always work as a wave travelling through a long floor wood, could dampen or distort quite quickly due to it's organic properties especially if that footstep sound has to also "hop" across to the next floor board etc.

Children
No Data