Patent attributes
A new process is synchronized to an existing process in the face of a communications delay (d) by collecting a history of delayed measurements and states of the existing process. This history and predetermined information regarding the behavior of the existing process are used to simulate the existing process forward in time to a current time, thereby computing a current process state. Once the current state is computed, the new process, driven by the same information, maintains synchronization with the existing process. In a document processor the method of synchronizing can be applied to tightly coupled modules. For example, a print media transport system includes a plurality of transport modules. Each transport module includes a plurality of transport actuators and an associated controller. Print media may be driven by actuators of plural modules contemporaneously. Modules about to receive media are synchronized to modules already transporting the media.