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Chapter 13
Reconfguration of Industrial
Embedded Control Systems
Mohamed Khalgui
Martin Luther University, Germany
Hans-Michael Hanisch
Martin Luther University, Germany
abstraCt
This research work deals with the development of safety reconfgurable embedded control systems fol-
lowing the international industrial component-based standard IEC61499. According to this standard, a
function block (FB) is a functional unit of software and a control application a FB network that has to
meet functional and temporal properties described in user requirements. We defne in the book chapter a
new semantic of the reconfguration where a crucial criterion to consider is the automatic improvement
of the system performance at run-time. If a reconfguration scenario is applied at run-time, then the FB
network implementing the system is totally changed or modifed. To handle all possible reconfguration
forms, we propose thereafter an agent-based architecture that applies automatic reconfgurations to adapt
the system according to well defned conditions and we model this agent with nested state machines ac-
cording to the formalism of net condition/event systems which is an extension of the Petri net formalism.
In order to satisfy user requirements, we specify the functional and temporal properties with the temporal
logic CTL (as well as its extensions ECTL and TCTL) and we apply the model checker SESA to check the
whole system behavior. To assign this reconfgurable system into the execution environment, we defne
thereafter an approach based on the exploration of reachability graphs to construct feasible OS tasks
that encode the FB network corresponding to each reconfguration scenario. Therefore, the system is
implemented with sets of OS tasks where each set is to load in memory when the corresponding scenario
is applied by the Agent. We developed the tool X-Reconfg to support these contributions that we apply
on the FESTO and EnAS benchmark production systems available in our research laboratory.
DOI: 10.4018/978-1-60566-750-8.ch013