User Manual

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Component Introduction
Rotary encoder
A rotary encoder, also called a shaft encoder, is an electro-mechanical device that
converts the angular position or motion of a shaft or axle to an analog or digital code.
There are two main types: absolute and incremental (relative). The output of
absolute encoders indicates the current position of the shaft, making them angle
transducers. The output of incremental encoders provides information about the
motion of the shaft, which is typically further processed elsewhere into information
such as speed, distance and position.
Rotary encoders are used in many applications that require precise shaft unlimited
rotation—including industrial controls, robotics, special purpose photographic
lenses, [1] computer input devices (such as optomechanical mice and trackballs),
controlled stress rheometers, and rotating radar platforms.