Hit Plate impact detection for .22 Long Rifle ammunition

Too tight and you will limit the sensor.
Too loose and the sensor will not register.
You may have to experiment with some shims to get the best result.

I'm extrapolating my experience here (we bonded the piezo to our next surface).

I can't do the dynamics in my head but if you bolt the piezo between a strap attached to the plate its not clear how the piezo will be compressed by the impact of the bullet.

I do know to maximize the signal you would bond the piezo to the plate, then bond a mass to the back of the Piezo (with no contact of this mass to the plate).

If you try your strap and get a feel for the results, then add some incompressible fluid between the piezo and the disk. If the performance takes a quantum jump then the epoxy will help if not then the strap is working.

It could work better to affix the larger plate to the target and add some mass in the form of an appropriately sized hex nut stuck to the smaller plate.  This should increase the generated signal without restricting the movement of the piezo plates.

I get the distinct impression that the impact of a rifle bullet will generate an extremely high voltage and substantial energy impulse. :astonished:

I agree. I think this falls into the category of "... its easier to test than to pontificate ..."

@mogilogic Just remember to put something in the input circuit to protect the processor from a high spike voltage.

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I promise you that the vibration of the plate will get picked up. You can use a BJT to amplify a weak signal but see if it won't flash a led you can detect with a photo-transistor, not an LDR.

If ant's feet make a signal....