Most existing methods for deadlock control in multi-unit resource systems are developed based on parallel multi-unit resource deadlock algorithms and their hardware implementation. However, the rapid dynamic changes in such resource allocation systems raise the following challenging problems: (a) how to model and control deadlocks in these systems in an alternative way as modeled by Petri nets, and (b) how to quickly and effectively make Petri nets able to adapt to these dynamic changes in such configurable systems. In order to cope with these problems, this study makes five contributions: (1) propose an efficient integrated policy for designing supervisors for multi-unit resource systems...
A multi-unit resource allocation system usually contains several processes and a number of resources with multiple units. Due to the competition for shared resources in these systems, deadlocks may occur. Recently, researchers have shown an increased awareness in deadlock control strategies for such a kind of systems without considering the dynamic changes such as processing failures and rework by using the Petri net paradigm. This article reports a new strategy for deadlock analysis and control in reconfigurable multi-unit resource systems (MRSs). We discuss a generalized class of Petri nets in which each stage of a process may require a number of units of different types of resources to...
Weighted Petri nets are common tools for modeling and validating discrete event systems involving resource allocation, such as flexible manufacturing systems (FMSs). A subclass of weighted Petri nets called a system of sequential systems with shared resources (S4R) has the power for modeling complex FMSs where the execution of an operation may require multiple resource types and multiple units of some resource types. Deadlock resolution is a crucial issue for the operation of an FMS. A direct and efficient policy is developed in this paper for detecting deadlock markings by extracting a weighted resource flow graph (WRFG) from an S4R and recovering them by synthesizing a recovery-transition...