JOINT FEEDFORWARD & FEEDBACK CONTROL OF A KEYED INKING UNIT

摘要

A method and system to control ink keys for a printing machine is provided. The ink keys are adjustable to control ink feed to individual zones located across the width of an ink roller. Feedforward and feedback control loops adjust the ink supply dynamically based on a pixel count of the image content. The pixel count looks ahead in the video stream to allow time for the adjustment at the inker keys to propagate through the ink train to affect ink output onto the imaging drum. Feedback of the achieved ink density on control patches on the imaging drum is also used to command the inker key motors. Feedback is also used to update the inker propagation delay and dynamic model used to determine how much the inker keys need to be adjusted based on the pixel count stream.