AMT optical encoder devices like the AMT103 have been used with SimpleFOC successfully… If your design can accommodate their size this type will be easier to use than the magnetic sensors mounted off-axis.
Thank you for your reply, the AMT103 would not work when we need slipring cables to pass.
Do you have any recommendation for magnetic sensors that is mounted off-axis that works with simplefoc?
Used where it may be difficult to slip a full ring encoder around a shaft. Allows removal and reinstall of shaft without removal of encoder.
These type of things make me wonder if it would be possible to repurpose an old hard drive or optical drive as a very high resolution absolute encoder. Write a specific pattern (grey code?) to a platter or CD and let the read head do its thing detecting the pattern. Disassembly and coupling to shaft without destruction would be the real trick.
I know the 3 phases of a hard drive motor can provide a useful encoderlike signal for something like a DJ scratch deck.