I just ordered a couple of hall effect sensors off Automation Direct.
I ordered Part - AE1-AN-2A. I figure these can be set up to sense a bolt head on the wheel. However - I worry about getting it consistently 2mm away and not having a collision between the sensor and the bolt head.
I have been playing with the idea of using the photoeye from 2 years ago.
These Rockwell (or Allen-Bradley) ones. However - they don't list a frequency.
So - those who have used these sensors - what kind of frequency were you able to get out of them?
One other question - since we are all probably looking at these for speed control of a shooting disk. How often do you set up your loop to measure the speed and adjust the power level to the motor? To often and you won't have enough counts to stay accurate. Not often enough and you don't zero in on the right speed quick enough.