On Modeling and Diagnosis of Discrete Event Dynamic Systems
1997 (English)Licentiate thesis, monograph (Other academic)
The basic motivation for this thesis is the fact that things go wrong. With the growing complexity of todays engineering systems, the need has arisen for systematic approaches to failure diagnosis. In this thesis an approach for modeling and diagnosis of systems that fall in the area of discrete event dynamic systems is proposed. The approach is applicable to all systems that at some level of abstraction have an interesting discrete event dynamics that can display faulty behavior. The systems suitable for this approach typically consist of several interacting components where abrupt, but non-catastrophic, faults can occur in the components.
We use a relational framework for discrete event dynamic systems focusing on a conceptually simple representation of the relationships between inputs, outputs and states of a discrete event system.
The modeling philosophy promoted here is to model faults locally, using special fault inputs or fault states only for that purpose. The diagnosis problem then basically is to infer the possible values of the unobservable fault inputs and states using the system model and observations of the real system.
A fault is said to be detectable if there exists a transition in the system model that leads to a detection in a finite number of steps. The transition necessary for detection can automatically be computed from the system model under certain conditions. We also show how to compute the finest possible fault partition.
Place, publisher, year, edition, pages
Linköping: Linköping University Electronic Press, 1997. , 78 p.
Linköping Studies in Science and Technology. Thesis, ISSN 0280-7971 ; 648
IdentifiersURN: urn:nbn:se:liu:diva-98118Local ID: LIU-TEK-LIC-1997:49ISBN: 91-7219-094-9 (print)OAI: oai:DiVA.org:liu-98118DiVA: diva2:652189
Ljung, Lennart, Professor