Hardware manual

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The small example how the Hall Sensor can be used to read the rotation of the rotor is
presented on the figure 3.3-1.
Fig. 3.3-1. Example how we can read impulses from Hall Sensor.
3.4. Incremental encoders.
Incremental encoder is a device which is used to measure the speed and a position. The general
idea of this tool is to converts motion into a sequence of digital pulses. Later, counting these
pulses we are able to estimate the relative or absolute position and the speed of the movement.
There are two configurations of encoders: linear and rotary. This last configuration has
additionally two forms: absolute and incremental. In absolute encoder, we have a unique

n, which allows us to estimate relative position of the shaft.
In most cases the encoder consists from a disk with holes, LED diode and photo sensor. The light
is continuously produced by the LED diode and when the disk rotates, the light is stopped or it
goes through some hole. When it passes through hole it is detected by the photo detector,
which generates impulse. The idea of the incremental encoder is presented on the figure 3.4-1.
Fig. 3.4-1. A typical example of rotary optical encoder.