FAULT-DETECTION MONITORING USING TIME PETRI NETS

While controlling manufacturing systems, real time data is collected t hrough sensory devices or some other means and fed back to the control ler for the purpose of monitoring that system. Monitoring refers to th e analysis of data collected from the system. It involves fault detect ion and diagnostics. Here, we shall emphasize the fault detection aspe cts of monitoring. Modeling the control system by a time Petri net per mits us to develop an analytical procedure for fault detection. By bac kfiring transitions in the time Petri net, we are able to determine if a given state is invalid. The back-firing approach also provides us w ith state space representation of time Petri nets and the maximum toke n holding times in different places of time Petri nets.