shock sensor for rotational motion detection?

[Kick]

Hi all,

I have a doubt regarding shock sensor. For rotational motion detection shock sensor is suitable? Our application is automotive (TPMS).
So far we did lot of test with different sensitivity. Almost all the test result showed us that it working only in vibration/shock.

We are using Murata's shock sensor and these sensors are only for TPMS application. Here is the link https://www.murata.com/en-eu/products/sensor/shock/tpms

Anyone have any suggestion please post here.

Thanks in advance.

 

[HTA]

Hi Kick,

what do you mean with shock for rotational motion? It could be twisting or speed variation on rotating elements, like a shaft.

Enjoy your design work!

 

[Kick]

Hi HTA,
thanks for your reply.

For testing we fixed sensor on scooter tire. When tire starts rotating sensor should detect and wake up uC. But currently this is not happening.
Mean while when we touch the shock sensor or if we put it on table(1-2cm height), uC will wake up. We tested with max tire speed of 1500rpm (not scooter tire, we have equipment for this).
So we are suspecting that this will work only in shock.

 

[FvM]

The Murata sensors linked in post #1 have a sensitivity of 0.8 mV/G, thus you get 0.8 mVpk AC when the wheel is rotating for the an circuit sensor. Not much, but apparently sufficient for a motion detector activating the TPMS pressure measurement and data transmission.

Usually a charge sensitive amplifier will be used as sensor preamplifier. You didn't tell at all how you interfaced the sensor and processed the sensor signal.