Determination of the ongoing position change of a functional element on an axis (e.g. the piston of a cylinder or valve) and feedback for processing in a closed circuit position control system.
The position feedback takes place in mechanically hydro-mechanical control systems using levers or spindles (e.g. for flight control or power steering (Figure W 7).
In hydro-electrical controls, electrical displacement transducers are used.
Figure W 7: Mechanical position feedback