Is it possible to build an RFID-based sensing system that could track the up and down movements of a machine part?
It depends. If you have open access to the part, and if the highest and lowest points that the item reaches are not too close together, it should be possible to affix a tiny passive low-frequency (LF) or high-frequency (HF) tag to the top and bottom of that component, and to then situate a small reader antenna at the highest and lowest points. The readers would interrogate the tags when the part reached each point. It would then be a matter of setting up software that would alert someone if the tags were not read at specific intervals. Such a solution could be built with equipment purchased over the Internet. I would say the biggest issues would involve affixing the tags via industrial adhesive, and being able to place the reader antennas in the proper positions to read them.
—Mark Roberti, Founder and Editor, RFID Journal