I need a sensor that will be able to tell whether a marker (e.g. a magnet, which is hand held) is nearby (e.g. distance <3mm), how closed is it (with a few mm accuracy), and most important of all - whether it’s moving or resting (= the eye can’t see any movement).
I thought about a linear hall sensor with a magnet but what sensor and what magnet type will give me the accuracy that I need? I saw that the SS49E Hall Effect sensor works only for distances > 5mm which is not optimal but how accurate is it? Will it catch 3mm changes in the location?
B/c I have the magnet in my hand I can’t use PIR movement and IR proximity sensors(*). B/c of the small distances I can’t use ultrasonic sensors. Camera sensor is possible solution which is expensive and cumbersome (the size of a hall sensor is optimal) so I hope to find better solution.
(*) if there’s a good distance/motion sensor that will track any obstacle in these ranges it’s better then no solution at all.