Improving the drop-consistency of an inkjet printhead using meniscus-based Iterative Learning Control

The performance of inkjet printheads is limited by residual vibrations and cross-talk, influencing the drop-consistency negatively. Given a certain printhead design, lifted ILC can be applied to design input wave forms that leave droplet formation undisturbed while minimizing these operational issues. The quality of the resulting pulses is largely dependent on the model´s representativeness of the jetting process. In particular, the choice of proper sensor functionality is a key issue. In this paper, a model based on the meniscus (ink-air interface in the nozzle) velocity as sensor signal is identified and taken as starting point for the implementation of so-called meniscus-based ILC. The suitability of this choice is shown by the implementation of the designed input pulses resulting in a considerable improvement of the drop-consistency