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Showing posts from January, 2023

Absolute Position Encoder Disk (Gray Code)

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Absolute position encoders are actually fairly rare, and I wanted to make my own for the sake of education. I decided to make an absolute position encoder with a 3D-printed disk and lasers used in tandem with photoresistors to detect position. With 5 bits of encoded data, this encoder can detect position with 360/(2^5) = 11.25 degrees of accuracy.  The huge bonus of absolute position encoders that many people don't realize is that the common relative position encoder can't remember a position unless the embedded system remains constantly powered. This problem can be somewhat alleviated by adding memory, but this complicates the system greatly, and doesn't help much in situations where there is consistent rotation, such as an anemometer, which was the use that I originally intended to use this design for.  This absolute position encoder I designed can be left unpowered for indiscriminate lengths of time and still provide accurate readings when polled. On this article is the