Haitham Hindi, Lara S. Crawford, and Markus P.J. Fromherz
This paper addresses the problem of controller state
synchronization in a networked control system with distributed sensing and
actuation, where actuators must hand off and switch controllers "on the fly" as
they go from performing one task to another, in the presence of fixed
communication delays and asynchronous measurements. We present a technique
that enables new controllers to seamlessly join and leave a task, by
encapsulating the controller in a finite state machine that handles the
synchronization. We also discuss issues related to the real-time
implementation of this technique and we finish with a demonstration on an
example from the document printing domain.