Skip to main content
SpringerLink
Log in
Book cover

International Symposium of Formal Methods Europe

FME 1993: FME '93: Industrial-Strength Formal Methods pp 388–402Cite as

Specifying a safety-critical control system in Z

  • Papers
  • Conference paper
  • First Online:

Part of the book series: Lecture Notes in Computer Science ((LNCS,volume 670))

Abstract

This paper presents a formal specification in the Z notation for a safety-critical control system. It describes a particular medical device but is quite generic and should be widely applicable. The specification emphasizes safety interlocking and other discontinuous features that are not considered in classical control theory. A method for calculating interlock conditions for particular operations from system safety assertions is proposed; it is similar to ordinary Z precondition calculation, but usually results in stronger pre-conditions. The specification is presented as a partially complete framework that can be edited and filled in with the specific features of a particular control system. Our system is large but the specification is concise. It is built up from components, subsystems, conditions and modes that are developed separately, but also accounts for behaviors that emerge at the system level. The specification illustrates several useful idioms of the Z notation, and demonstrates that an object-oriented specification style can be expressed in ordinary Z.

This is a preview of subscription content, log in via an institution.

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

References

  1. Dan Craigen. FM89: Assessment of formal methods for trustworthy computer systems. In 12th International Conference on Software Engineering Proceedings, pages 233–235, IEEE Computer Society, 1990.

    Google Scholar 

  2. Gene F. Franklin, J. David Powell, and Abbas Emami-Naeini. Feedback Control of Dynamic Systems. Addison-Wesley, second edition, 1991.

    Google Scholar 

  3. David Garlan and Norman Delisle. Formal specifications as reusable frameworks. In D. Bjorner, C. A. R. Hoare, and H. Langmaack, editors, VDM '90: VDM and Z — Formal Methods in Software Development, pages 150–163, Third International Symposium of VDM Europe, Springer-Verlag, Kiel, FRG, April 1990. Lecture Notes in Computer Science number 428.

    Google Scholar 

  4. K.L. Heninger. Specifying software requirements for complex systems: new techniques and their application. IEEE Transactions on Software Engineering, SE-6(1):2–13, 1980.

    Google Scholar 

  5. Jonathan Jacky. Formal Specification and Development of Control System Input/Output. Technical Report 92-05-02, Radiation Oncology Department, University of Washington, Seattle, WA, May 1992.

    Google Scholar 

  6. Jonathan Jacky. Formal specifications for a clinical cyclotron control system. In Mark Moriconi, editor, Proceedings of the ACM SIGSOFT International Workshop on Formal Methods in Software Development, pages 45–54, Napa, California, USA, May 9–11 1990. (also in ACM Software Engineering Notes, 15(4), Sept. 1990).

    Google Scholar 

  7. Jonathan Jacky, Ruedi Risler, Ira Kalet, and Peter Wootton. Clinical Neutron Therapy System, Control System Specification, Part I: System Overview and Hardware Organization. Technical Report 90-12-01, Radiation Oncology Department, University of Washington, Seattle, WA, December 1990.

    Google Scholar 

  8. Jonathan Jacky, Ruedi Risler, Ira Kalet, Peter Wootton, and Stan Brossard. Clinical Neutron Therapy System, Control System Specification, Part II: User Operations. Technical Report 92-05-01, Radiation Oncology Department, University of Washington, Seattle, WA, May 1992.

    Google Scholar 

  9. Matthew S. Jaffe, Nancy G. Leveson, Mats P. E. Heimdahl, and Bonnie E. Melhart. Software requirements analysis for real-time process control systems. IEEE Transactions on Software Engineering, 17(3):241–258, March 1991.

    Article  Google Scholar 

  10. Ruaridh Macdonald. Z Usage and Abusage. Technical Report 91003, Royal Signals and Radar Establishment, St. Andrews Road, Malvern, Worcestershire, WR14 3PS, February 1991.

    Google Scholar 

  11. Carroll Morgan and Bernard Sufrin. Specification of the UNIX file system. IEEE Transactions on Software Engineering, SE-10(2):128–142, March 1984.

    Google Scholar 

  12. David Lorge Parnas and Jan Madey. Functional Documentation for Computer Systems Engineering (Version 2). Technical Report, Telecommunications Research Institute of Ontario (TRIO), McMaster University, Hamilton, Ontario, L8S 4K1, September 1991. CRL Report No. 237.

    Google Scholar 

  13. Ben Potter, Jane Sinclair, and David Till. An Introduction to Formal Specification and Z. Prentice Hall International (UK) Ltd, Hemel Hempstead, Hertfordshire, 1991.

    Google Scholar 

  14. Ruedi Risler, Jüri Eenmaa, Jonathan P. Jacky, Ira J. Kalet, Peter Wootton, and S. Lindbaeck. Installation of the cyclotron based clinical neutron therapy system in Seattle. In Proceedings of the Tenth International Conference on Cyclotrons and their Applications, pages 428–430, IEEE, East Lansing, Michigan, May 1984.

    Google Scholar 

  15. J. M. Spivey. The Z Notation: A Reference Manual. Prentice-Hall, New York, 1989.

    Google Scholar 

  16. Susan Stepney, Rosalind Barden, and David Cooper. A survey of object orientation in Z. Software Engineering Journal, 7(2):150–160, March 1992.

    Google Scholar 

Download references

Author information

Authors and Affiliations

  1. Department of Radiation Oncology RC-08, University of Washington, 98195, Seattle, WA, USA

    Jonathan Jacky

Authors
  1. Jonathan Jacky
    View author publications

    You can also search for this author in PubMed Google Scholar

Editor information

James C. P. Woodcock Peter G. Larsen

Rights and permissions

Reprints and permissions

Copyright information

© 1993 Springer-Verlag Berlin Heidelberg

About this paper

Cite this paper

Jacky, J. (1993). Specifying a safety-critical control system in Z. In: Woodcock, J.C.P., Larsen, P.G. (eds) FME '93: Industrial-Strength Formal Methods. FME 1993. Lecture Notes in Computer Science, vol 670. Springer, Berlin, Heidelberg. https://doi.org/10.1007/BFb0024658

Download citation

  • DOI: https://doi.org/10.1007/BFb0024658

  • Published:

  • Publisher Name: Springer, Berlin, Heidelberg

  • Print ISBN: 978-3-540-56662-5

  • Online ISBN: 978-3-540-47623-8

  • eBook Packages: Springer Book Archive

Publish with us

Policies and ethics

Search

Navigation