Vibration monitoring (pumps etc.)

Hardware
1

My view on vibration monitoring is that you separate out the sensor monitoring vibration from the MCU+datalogging, which you would mount in a less hostile environment. However, I’ve come across more and more integrated units, especially those which offer wifi communication, which are mounted directly on a vibrating machine.

Now wondering what is this a safe approach to take for IIOT.

Certainly, integrated units are cheaper to produce but they may not last as long or worse still they lose accuracy, if say oscillator gets damage or other components start to degrade due to fatigue.

So does anyone know what the long-term effects are of vibration on a PCB and mounted components (oscillators, antenna etc.) and at what threshold (amplitude or frequency) do things degrade quicker.

Also a novice question. I’ve heard of the doppler effect on wireless transmission caused by movement. Does this apply or impact packet loss/transmission distance, if an antenna is on a vibrating machine etc?

2

There are already imp-based products in this field, eg https://petasense.com/ who use the imp003.

I know they use a flex circuit PCB in the product, but the relatively low masses of the parts involved (all SMT) likely helps mitigate the effects of vibration as much as anything else.

Doppler effect is not going to be an issue; even (eg) using cellular devices on planes going hundreds of miles an hour isn’t a problem (the issue there is the network handoffs when you change cells rapidly).