Hierarchical interface-based supervisory Control-part II: Parallel case

by Ryan J. Leduc, Mark Lawford, W.M. Wonham


In this paper, we present a hierarchical method that decomposes a discrete-event system (DES) into a high-level subsystem which communicates with n≥1 parallel low-level subsystems, through separate interfaces which restrict the interaction of the subsystems. It is a generalization of the serial case (n=1) described in Part I of this paper, where we define an interface and a set of interface consistency properties that can be used to verify if a DES is nonblocking and controllable. Each clause of the definition can be verified using a single subsystem; thus the complete system model never needs to be stored in memory, offering potentially significant savings in computational resources. We provide algorithms for verifying these new properties, and briefly discuss the computational complexity of the method. Finally, we present an application to a large manufacturing example with an estimated worst-case closed-loop state-space size of 2.9×10 to the 21.


BibTeX Entry

title={Hierarchical interface-based supervisory control-part II: parallel case},
author={Leduc, R.J. and Lawford, M. and Wonham, W.M.},
journal={Automatic Control, IEEE Transactions on},
pages={ 1336-1348},
keywords={ automata theory, computational complexity, discrete event systems, hierarchical systems computational complexity, discrete-event system, formal method, hierarchical interface-based supervisory control, hierarchical systems, high-level system, interface consistency, system model},
ISSN={0018-9286}, }

Mark Lawford
Last modified: Wed May 27 16:50:40 EDT 2009