A new machine control method and system for registering pre-produced webs into
a converting line producing disposable absorbent articles such as diapers, pull-ups,
feminine hygiene articles or a component thereof. The pre-produced webs can include
a multiplicity of pre-produced objects spaced on the web at a pitch interval in
the web direction. The pre-produced web being manipulated in order for the pre-produced
object of the web to be registered in relation to a target position. The present
invention includes five embodiments, where the first embodiment is expressed as
a generic claim. The first embodiment includes a closed-loop feedback registration
system; the second and third embodiments, in addition, include an open-loop feedforward
control system; the fourth and fifth embodiments, in addition, include an automatic
phasing system. In addition, the third embodiment uses a machine vision system
to recognize any element of a complex pre-produced object (e.g., colorful graphics).