Hydraulic servomechanism

Fig. 4.42 Hydraulic servomechanism with walking beam feedback linkage.

Another essential component in the functioning of automated processes and servomechanisms is the feedback control systems that provide self-regulation and auto-adjustment of the overall system. Feedback control systems may be pneumatic, hydraulic, mechanical, or electrical in nature. Electrical feedback may be analogue in form, although digital electronic feedback methods provide the most versatile method of output sensing for input feedback to digital electronic control systems. 

Servomechanisms are devices used to control motion. Two basic types involve hydraulic or electromechanical drives. The latter t) es involve stepping motors or DC variable speed motors. A stepping motor receives controlled pulses of energy that cause stepwise rotation in response to each pulse. 

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