Marking estimation of fuzzy Petri nets

In this paper we deal with the problem of designing an observer for Petri nets under the assumption that all transitions may be observed but there exist some uncertainties in the initial marking. In particular, the information on the initial marking is given in terms of fuzzy markings by associating a discrete membership function with each place. Some ideas on how to extend the proposed approach to the case of unobservable transitions are also discussed.