Capacitive sensors give very high performance. Unfortunately, they require a driver system and generally some tuning. Optical reflective sensors can require a bit of dong to make work well for a gear, but they are very cheap, come in a number of pac…
An often overlooked encoder for some low to moderate speed applications is the optical mouse chip. It can work with performance similar to a 1024 cpi linear encoder, can provide feedback for multiple axes (the output is a vector rather than a simple…