Abstract
Petri nets are robust mathematical tools for the modelling, handling, and control of deadlock problems in automated manufacturing systems (AMSs). Several methods have been proposed to prevent deadlocks in AMSs. However, it is important to convert the controlled system represented by Petri nets into the program of a programmable logic controller (PLC) for the implementation of automation tasks. This study proposes a methodology based on Petri nets for deadlock prevention, and generates PLC codes for an AMS. In the suggested methodology, a Petri net model of an uncontrolled system is built, and the controlled Petri net model is developed using a deadlock-prevention method. The controlled Petri net model is then transformed into an automation-controlled Petri net model, which is further converted into a controlled token-passing logic model. The controlled token-passing logic model is utilised to generate the ladder diagrams for the AMS under consideration. The proposed methodology was tested using a real-world AMS at King Saud University labs. It provides an effective method for PLC implementation from a controlled system model represented by Petri nets.
Petri-nette is robuuste wiskundige instrumente wat gebruik word om dooiepunt probleme in geoutomatiseerde vervaardigingstelsels (AMSe) te modelleer, hanteer en te beheer. Verskeie metodes is al voorgestel om dooiepunte in AMSe te verhoed, maar dit is belangrik om die beheerde stelsel deur die Petri-nette voorgestel om te skakel na die rekenaarkode van 'n programmeerbare logiese beheerder (PLC) sodat dit geïmplementeer kan word. 'n Metodologie gegrond op Petri-nette vir dooiepunt voorkoming word voorgehou en genereer PLC rekenaarkode vir AMSe. In die voorgestelde metodologie word n Petri-netmodel van n onbeheerde stelsel geskep en die beheerde Petri-netmodel is dan ontwikkel met die dooiepuntvoorkomingsmetode. Die beheerde Petri-net model word dan getransformeer tot 'n outomasiebeheerde Petri-netmodel wat dan verder omskep word in n beheerde kenteken-aanstuur logiese model. Hierdie model word dan gebruik om leerdiagramme vir die AMS te genereer. Dié metodologie is getoets in 'n reële wêreld AMS by die King Saudi Universiteit se laboratoriums. Dit verskaf n effektiewe metode vir PLC implementering van n beheerde stelsel wat deur Petri-nette voorgestel word.