Need Solution for Peculiar Ring/Pointer Problem

[Maddy]

That sounds good. But what if the pointer is taken away from the ring
and brought back to an arbitrary position and I want to know its
absolute position on the ring (The ring is engraved from 0 to 360)?

 

[Robert Baer]

That sounds good. But what if the pointer is taken away from the ring
and brought back to an arbitrary position and I want to know its
absolute position on the ring (The ring is engraved from 0 to 360)?

Well, if the encoder / pickup is attached or a part of the "pointer",
then that composite will be positioned (rotated) as a unit, solving the
"problem".