Digital Control Algorithms for Web-Offset Inking

The development of digital control algorithms for an integrated web-offset inking control system for the Technical Research Centre of Finland's full-scale laboratory press, and the newly implemented control structure with presetting characteristics are discussed. The ink consumption of a press zone determines the feedback gain of the corresponding ink screw algorithm. The estimator-based digital controller enables an on-press densitometer to be positioned rather freely in a multi-unit production press.