What are incremental encoders ?Are they useful to us in any way?
Increment encoders are optical encoders that are frequently used in control systems to convert linear or rotory displacement into digital code or pulse signals. Their output is a pulse for each increment of resolution but these make no distinction between increments.
An incremental encoder typically has four parts:a light source(LED),a rotory (or translatory) disc ,a stationary mask and a sensor (photodiode) .The disc has alternate opaque and transparent sectors which are etched by means of photographic process on to a plastic disc.(slots are cut out in case a metal disc is used).As disc rotates during half of the increment cycle the transparent sectors of rotating and stationary discs come in alignment permitting the light from LED to reach the sensor thereby generating an electric pulse .
The waveform of the sensor output of an encoder is generally triangular or sinusoidal depending upon the resolution required.Square wave signal compatible with digital logic are obtained from it by me
ans of linear OPAM and comparator.The resolution of incremental encoders are given by
Increment encoders are optical encoders that are frequently used in control systems to convert linear or rotory displacement into digital code or pulse signals. Their output is a pulse for each increment of resolution but these make no distinction between increments.
An incremental encoder typically has four parts:a light source(LED),a rotory (or translatory) disc ,a stationary mask and a sensor (photodiode) .The disc has alternate opaque and transparent sectors which are etched by means of photographic process on to a plastic disc.(slots are cut out in case a metal disc is used).As disc rotates during half of the increment cycle the transparent sectors of rotating and stationary discs come in alignment permitting the light from LED to reach the sensor thereby generating an electric pulse .
The waveform of the sensor output of an encoder is generally triangular or sinusoidal depending upon the resolution required.Square wave signal compatible with digital logic are obtained from it by me
ans of linear OPAM and comparator.The resolution of incremental encoders are given byBasic resolution =360/N where N=number of sectors of disc:each sector is half transparent and half opaque.
Reference:
(1)Control Systems Engineering-I.J Nagarath,M.Gopal
(2)Control Systems Engineering-S.N Sivanandam
(1)Control Systems Engineering-I.J Nagarath,M.Gopal
(2)Control Systems Engineering-S.N Sivanandam
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