An admissible-behaviour-based analysis of the deadlock in Petri-net controllers

Abstract This paper addresses the problem of verifying the discrete control logic that is typically implemented by programmable controllers. Not only are the logical properties of the controller studied during verification, the behaviour of the overall controlled system is also examined. An approach that combines the calculation of the safety-oriented interlock controllers in terms of supervisory control theory (SCT), the corresponding calculation of the admissible behaviour of the system, and the specification of the desired system operation by Petri nets is proposed. A potential deadlock in the controlled system is then verified by taking the admissible-behaviour model as a process model. The analysis of the simultaneously operated supervisory-control-based interlock controller and the Petri-net-based sequential controller is performed with a C-reachability graph. The paper focuses on the calculation of the graph, and the approach is illustrated with an example of a simple manufacturing cell.

[1]  Lothar Litz,et al.  Formal methods in PLC programming , 2000, Smc 2000 conference proceedings. 2000 ieee international conference on systems, man and cybernetics. 'cybernetics evolving to systems, humans, organizations, and their complex interactions' (cat. no.0.

[2]  M.H. de Queiroz,et al.  Synthesis and implementation of local modular supervisory control for a manufacturing cell , 2002, Sixth International Workshop on Discrete Event Systems, 2002. Proceedings..

[3]  MengChu Zhou,et al.  Ladder diagram and Petri-net-based discrete-event control design methods , 2004, IEEE Trans. Syst. Man Cybern. Part C.

[4]  Antti Valmari,et al.  The State Explosion Problem , 1996, Petri Nets.

[5]  Mohsen A. Jafari,et al.  Modeling admissible behavior using event signals , 2004, IEEE Transactions on Systems, Man, and Cybernetics, Part B (Cybernetics).

[6]  Lothar Litz,et al.  Verification and validation of control algorithms by coupling of interpreted Petri nets , 1998, SMC'98 Conference Proceedings. 1998 IEEE International Conference on Systems, Man, and Cybernetics (Cat. No.98CH36218).

[7]  Ratnesh Kumar,et al.  Automated control synthesis for an assembly line using discrete event system control theory , 2003, IEEE Trans. Syst. Man Cybern. Part C.

[8]  Bruce H. Krogh,et al.  Formal verification of PLC programs , 1998, Proceedings of the 1998 American Control Conference. ACC (IEEE Cat. No.98CH36207).

[9]  Drago Matko,et al.  MODEL BASED PROGRAMMABLE CONTROL LOGIC DESIGN , 2002 .

[10]  D. Matko,et al.  Petri net control of systems under discrete-event supervision , 2003, 2003 European Control Conference (ECC).

[11]  Valeriy Vyatkin,et al.  Formal validation of intelligent-automated production systems: towards industrial applications , 2006, Int. J. Manuf. Technol. Manag..

[12]  Drago Matko,et al.  COMBINED SYNTHESIS/VERIFICATION APPROACH TO PROGRAMMABLE LOGIC CONTROL OF A PRODUCTION LINE , 2005 .

[13]  Christos G. Cassandras,et al.  Introduction to Discrete Event Systems , 1999, The Kluwer International Series on Discrete Event Dynamic Systems.

[14]  Peng Zhao,et al.  Modeling admissible behavior using event signals , 2004, IEEE Trans. Syst. Man Cybern. Part B.

[15]  Hans-Michael Hanisch,et al.  A modular plant modeling technique and related controller synthesis problems , 1998, SMC'98 Conference Proceedings. 1998 IEEE International Conference on Systems, Man, and Cybernetics (Cat. No.98CH36218).

[16]  P. Ramadge,et al.  Supervisory control of a class of discrete event processes , 1987 .

[17]  MengChu Zhou,et al.  Design of industrial automated systems via relay ladder logic programming and Petri nets , 1998, IEEE Trans. Syst. Man Cybern. Part C.

[18]  Carlos Eduardo Pereira,et al.  Manufacturing plant control: Challenges and issues , 2007 .

[19]  Timothy L. Johnson Improving automation software dependability: A role for formal methods? , 2004 .

[20]  Tadao Murata,et al.  Petri nets: Properties, analysis and applications , 1989, Proc. IEEE.