CMS – The Detector Control System

1. ACEOLE Six Month Meeting CMS – The Detector Control System Yi Ling Hwong This research project is supported by the Marie Curie Initial Training Network Fellowship of the European Community’s Seventh Framework Programme under contract number (PITN-GA-2008-211801-ACEOLE)

2. Overview • Introduction to the CMS Detector Control System • PVSS and JCOP Framework • Why and how? • Finite State Machine • Tools and Applications • Analysis of current FSM tree • Background and objectives

3. The Detector Control System (DCS) • DCS • CMS is a collaboration of more than 35 countries • Control system design and implementation is distributed among collaborators • A need for a central control system • A set of policies managing and governing all activity • Main purpose: ensure the correct operation of the CMS experiment • Scope: all subsystems and its active elements, the electronics on and off the detector and the overall environment • PVSS/JCOP Framework DCS Devices (HV, LV, GAS, Cooling, etc.) • Finite State Machine Detector Channels L0 TFC Front End Electronics • DEN Readout Network Experiment Control System • Background andObjective HLT Farm Storage • Conclusion Monitoring Farm DAQ Illustration inspired by Clara Gasper’s presentation for CHEP 2009 External Systems (LHC, Technical Services, Safety, etc)

4. The CMS DCS • DCS • The DCS of individual sub-detectors are connected to the central DCS Supervisor • Global Services • 7 Sub-Detectors Controls • PVSS/JCOP Framework • Finite State Machine • DEN • Background andObjective • Conclusion

5. Custom Commercial FSM Supervision SCADA Process DIM OPC Management Communication Protocols VME PLC/UNICOS Field Management Field buses & Nodes Sensors/devices Control Technologies from LHC Era • DCS Technologies • PVSS/JCOP Framework Layer Structure Configuration DB, Archives, Storage Log files, etc. • Finite State Machine WAN LAN • DEN LAN • Background andObjective Controller/ PLC Other systems (LHC, Safety, ...) VME Field Bus Node Node • Conclusion Experimental equipment Based on an original idea from LHCb

6. DCS DetDcs1 DetDcsN SubSys1 SubSys2 SubSysn Dev1 Dev2 Dev3 Devi Devn Requirements • DCS • Large number of devices / IO Channels • For CMS - Around 6 million parameters • Distributed over 100 PCs • Need for • Parallel and distributed control system • Hierarchical control • Decentralized decision making • PVSS/JCOP Framework • Finite State Machine • DEN • Background andObjective • Conclusion 6 19 September 2014 Yi Ling Hwong

7. What is JCOP? • DCS • Stands for “Joint COntrols Project” • Grouping of representatives from the 4 big LHC experiments • Offer common experiment components and support (e.g. CAEN, ELMB etc) • Aims to reduce the overall manpower cost required to produce and run the experiment control systems • Reduce knowledge of tools • Interface for non-experts • PVSS/JCOP Framework • Finite State Machine • DEN • BackgroundandObjective • Conclusion

8. What is JCOP Framework? • DCS • A set of guidelines and tools • Produced in collaboration, components shared • Produced using common tools • Aims for homogeneity • The framework is based on: • SCADA system – PVSS • Device Description (Run-time Database) • Device Access (OPC, Profibus, drivers) • Alarm Handling (Generation, Filtering, etc) • User Interface Builder • Etc … • SMI++ • Abstract behavior modeling (Finite State Machine toolkit) • PVSS/JCOP Framework • Finite State Machine • DEN • BackgroundandObjective • Conclusion

9. JCOP Framework • DCS • Covers all levels down to the connection to the hardware • Majority of the framework is provided at the supervisory level • Connection of other front-ends is possible via one of the communication interfaces • OPC, DIM or DIP • PVSS/JCOP Framework • Finite State Machine • DEN • BackgroundandObjective • Conclusion

10. JCOP Framework • DCS • Components provided by framework • Generic Analog-Digital devices • CAEN Power Supplies • Wiener Power Supplies • ELMB • PS and SPS machine data server • Logical Node/View • Device Editor/Navigator • Trending Tool • Etc • PVSS/JCOP Framework • Finite State Machine • DEN • BackgroundandObjective • Conclusion

11. What is FSM? • DCS • Abstract representation of the experiment • Control system is modelled as a hierarchy of FSM • A generic, data-driven mechanism for modelling the functionality of a piece of equipment or a subsystem • A state/command interface between a parent and its children • What state is it in? Is it taking data? Is it in standby? Is it broken? Is it switched off? What triggers it to move from one of these states to another? • Two types of objects are defined: • Control Unit • A software entity that monitors the state of its children • Device Unit • A software entity that represents some hardware • PVSS/JCOP Framework • Finite State Machine • DEN • BackgroundandObjective • Conclusion

12. FSM Model • DCS • A simple control system modelled using FSM • Nodes have only one parent • No horizontal lines • Commands go down, States propagated up • PVSS/JCOP Framework • Finite State Machine • DEN • BackgroundandObjective • Conclusion

13. Control and Device Units • DCS • State Transition Diagram for a CU • State Transition Diagram for a DU • PVSS/JCOP Framework • Finite State Machine • DEN • BackgroundandObjective • Conclusion

14. SMI Domain Obj SMI Domain Obj Obj Obj Obj Obj Obj Obj Proxy Proxy Proxy SMI ++ • Logically related objects can be grouped inside “SMI domains” to represent a sub-system • Only one object (top level object) is accessed by other objects • Important attributes: State and Action • DCS • JCOP chose the State Management Interface (SMI ++) product which was developed for the Delphi experiment • SMI = Tool to build a FMS + Expert system • Real world is viewed as a collection of objects behaving as FSM • Represent hardware devices, software tasks or abstract subsystem • SMI ++ objects distributed over various platforms • Communication through DIM • PVSS/JCOP Framework • Finite State Machine • DEN • BackgroundandObjective • Conclusion Hardware Devices

15. State Management Language • DCS • A special language is provided for the object description – State Management Language (SML) • Interpreted by a Logic Engine (coded in C++) to drive the control system • An SML file corresponds to an SMI domain • PVSS/JCOP Framework • Finite State Machine • DEN • BackgroundandObjective • Conclusion

16. Device Editor and Navigator (DEN) • DCS • Main interface to the Framework • System management • Configuration and operation of device • Editor and Navigator mode • Hardware, logical and FSM view • PVSS/JCOP Framework • Finite State Machine • DEN • BackgroundandObjective • Conclusion

17. Device Unit Type Configurations • DCS • PVSS/JCOP Framework • Finite State Machine • DEN • BackgroundandObjective • Conclusion

18. Logical Object Type Configuration • DCS • PVSS/JCOP Framework • Finite State Machine • DEN • BackgroundandObjective • Conclusion

19. Navigator Mode • DCS • View the hierarchy starting from any control unit • PVSS/JCOP Framework • Finite State Machine • DEN • BackgroundandObjective • Conclusion

20. Navigator Mode • DCS • Partitioning, actions etc • PVSS/JCOP Framework • Finite State Machine • DEN • BackgroundandObjective • Conclusion

21. Background • DCS • Background of project • Large number of independent teams • High complexity • Very different operational mode • Common problems in developing the FSMs: • Repetitive and redundant logic • Inconsistency (endless loops) • Inhomogeneity • PVSS/JCOP Framework • Finite State Machine • DEN • Background andObjective • Conclusion

22. Objectives • DCS • Understanding of DCS tools and application • Development of an analysis tool to analyze the FSM trees in the CMS DCS • Optimization and thorough analysis of the current FSM system • Provide a mechanism to ensure homogeneity in the FSMs • Development of a visualization program • PVSS/JCOP Framework • Finite State Machine • DEN • Background andObjective • Conclusion

23. Plans • DCS • Training courses and conferences • Oracle SQL course (2nd Feb – 4th Feb) • PVSS/JCOP Framework training course (9th Feb – 13th Feb) • FSM course (17th Feb – 19th Feb) • General and professional French course (26th Jan – 3rd April) • Programming in JAVA (27th April – 29th April) • CHEP (23rd Mar – 27th Mar) • RT2009 (10th May – 15th May) • ICALEPCS (12th Oct – 16th Oct) : Abstract submitted • Exportation of FSM into Database • Analysis and building of the complex FSM trees • Possible collaboration with Eindhoven University of Technology • Proposal written and meeting planned • PVSS/JCOP Framework • Finite State Machine • DEN • Background andObjective • Conclusion

24. Conclusion • DCS • The Detector Control System is an integral part of the CMS experiment and is large and complex • A homogenous and coherent control system has been developed using the JCOP framework • PVSS and SMI++ are being used in the framework, and its tools and applications have been proven to be useful and user-intuitive • However, inhomogeneity and incoherence in the FSM development still exist, an analysis tool is foreseen to be developed and implemented • PVSS/JCOP Framework • Finite State Machine • DEN • Background andObjective • Conclusion

25. Thank you for your attention!