Closed Loop Controls

What´s the difference between a opened and closed loop control?

Block diagram of an opened loop control

Block diagram of an opened loop control

The signal flow has an start point and an end point. Therefore you also name this as an opened loop control. The problem is hereby: This control cannot react o disturbances.

In order to reach the desired position safely despite of disturbing influences, the circuit has to be complemented to a closed loop control. Which further components you need?

The block diagram of a closed-loop control in general can now completed:

Block diagram and function of a closed loop control

Block diagram and function of a closed loop control