Blanking-bending process chain with disturbance feed-forward and closed-loop control

Bending and other manufacturing processes are subject to uncertain process conditions like varying properties of the semi-finished parts. In order to obtain precise bending angles, these variations have to be compensated. Upstream processes often deliver valuable information about the actual part properties. This paper presents a blanking-bending process chain in which information from the blanking process is passed on to the bending process. A feed-forward bending controller uses this information as input state and compensates deviations from the nominal state. In a second instance, a closed-loop controller addresses model uncertainty of the feed-forward controller as well as unknown disturbances. A model-based closed-loop control design is shown which increases stability, stationary accuracy and time-optimality.