What's an appropriate sensor for cheaply and accurately measuring an angle of rotation?
I'm trying to measure the angle of a joint in a robotic limb using a small potentiometer mounted at the axis of rotation, and although it's small and inexpensive, it's accuracy and susceptibility to noise is horrible.
I need something equally small and cheap, but much more accurate.
The only other technology that comes close are hall effect sensors. I've seen some SoC that can detect a rotating magnet above them and output the angle as a signal. However, I can't find any of them packaged in a form that's as small as a potentiometer.
Do any of these come in small package sizes? What's their accuracy compared to a potentiometer measured with an ADC? How much more immune would a hall effect sensor be?