Combined centralized and decentralized fault diagnosis for discrete event systems

Karav, Ruhi
Discrete Event Systems (DES) are used for modeling systems such as manufacturing systems, telecommunication systems and transportation systems. It is possible to incorporate the fault model in the DES model together with a fault diagnosis approach to evaluate the robustness and the reliability of the system at the design stage. There are centralized or decentralized fault diagnosis approaches in the literature. The centralized fault diagnosis achieves stronger results however it does not scale to reasonably large systems because of its complexity. The decentralized diagnosis is applicable to real-life systems with a cost of possible misses of faults. This thesis proposes a combination of centralized and decentralized fault diagnosis for DES models. To this end, the thesis makes use of the observation that some parts of the faulty DES behavior might be detected by decentralized diagnosis while other parts need a centralized diagnoser. Hence, the overall complexity of the diagnosis is reduced while maintaining the ability to detect all faults. The thesis proposes a systematic diagnosis approach together with the algorithms and practical applications to manufacturing system and communication network examples.


Diagnosers for discrete event systems: improved realization and examples
Kart, Bora Eser; Schmidt, Şenan Ece; Schmidt, Klaus Werner; Department of Electrical and Electronics Engineering (2014)
Many complex systems in different areas such as manufacturing, telecommunications or transportation can be modeled as Discrete Event Systems (DES). The task of fault detection and isolation is naturally desired for every system that has the possibility of any fault occurrences in it. To this end, a DES machine that can detect every modeled fault after a bounded number of event occurrence called diagnoser is used. In this thesis, there are two diagnoser realizations corresponding to the notions of event and ...
Real-time hardware-in-the-loop simulation of electrical machine systems using FPGAs
Üşenme, Serdar; Dilan, R.A.; Dölen, Melik; Koku, Ahmet Buğra (2009-11-18)
This study focuses on the development an integrated software and hardware platform that is capable of performing real-time simulation of dynamic systems, including electrical machinery, for the purpose of hardware-in-the-loop simulation (HILS). The system to be controlled is first defined using a block diagram editor. The defined model is then compiled and downloaded onto an FPGA (¿Field Programmable Gate Array¿) based hardware platform, which is to interface with the controller under test and carry out the...
Efficient Abstractions for the Supervisory Control of Modular Discrete Event Systems
Schmidt, Klaus Verner (2012-12-01)
The topic of this technical note is the nonblocking and maximally permissive abstraction-based supervisory control for modular discrete event systems (DES). It is shown, that an efficient abstraction technique, that was developed for the nonconflict verification of modular DES, is also suitable for the nonblocking supervisory control. Moreover, it is proved that this abstraction technique can be extended by the condition of local control consistency, in order to achieve maximally permissive supervision. Dif...
Fuzzy Hybrid Systems modeling with application in decision making and control
Boutalis, Yiannis; Moor, Thomas; Schmidt, Klaus Verner (2012-11-28)
Hybrid Systems are systems containing both discrete event and continuous variable components. Many recent contributions address crisp situations, where ambiguity or subjectivity in the measured data is absent. In this paper, we propose Fuzzy Hybrid Systems to account for inaccurate measurements and uncertain dynamics. We present a strategy to determine the most appropriate control actions in a sampled data setting. The proposed approach is based on three basic steps that are performed in each sampling perio...
Improved Parallel Preconditioners for Multiphysics Topology Optimizations
Akay, Hasan Umur; Oktay, Erdal; Manguoğlu, Murat; Sivas, Abdullah Ali (2015-05-17)
Topology optimization, also known as layout optimization, involves multiple physics encompassing structural, thermal, fluidic electrical and electromechanical systems including coupled phenomena such as solids and fluids as in convective cooling systems, aerodynamical systems, electronics, actuators and motors. In the root of topology optimization is the repeated solution of the finite element equations Au = f representing the physics of the problem at hand such as elasticity, heat transfer, fluid flow and ...
Citation Formats
R. Karav, “Combined centralized and decentralized fault diagnosis for discrete event systems,” M.S. - Master of Science, Middle East Technical University, 2014.