Enabling higher jet frequencies for an inkjet printhead using iterative learning control

Inkjet printheads operate thanks to resonating fluid-mechanics. At the same time, however, this limits the maximally attainable jetting frequency since the residual vibrations must be damped first prior to jetting a next droplet. This paper presents an approach based on lifted ILC with which input wave forms are designed that leave the droplet formation undisturbed while bringing the channel to a rest quickly after droplet ejection. This paper shows the modeling required for ILC, the design of the ILC controller in the lifted setting with separate observation and actuation windows, and the experimental implementation