1. nearly
Formal Methods
Automatic Validation and Verification Tools
Kim Guldstrand Larsen
Institute of Computer Science
Aalborg University
Formal Methods seems to be finding its way into industrial software engineering practice. In particular, methods based on fully automatic verification tools have for a long time been established practice for hardware designs.
Today, an increasing number of (commercial) tools offering automatic verification support for industrial designs of embedded systems, real-time systems, and communication protocols are emerging.
The scalability of these tools has been significantly improved due to recent, scientific advances in the underlying algorithmic techniques, which have allowed for large industrial applications to be verified.
The talk will present the tool UPPAAL, a tool suite for validating and verifying real-time system models. The tool has been developed since 1995 in collaboration between Aalborg and Uppsala Universities. The presentation will be based on on-line demonstration and survey the industrial applications of UPPAAL.
The final part of the talk will address the tool visualSTATE, a commercial tool for automatic validation and verification of embedded system models In addition visualSTATE allows for automatic generation of efficient code for a number of platforms. Resent collaboration between visualSTATE, and DTU has resulted in truely significant advances in the size of systems which may be dealt with.
Hybrid Systems from timed automata to hybrid systems – and back Kim Guldstrand Larsen Paul Pettersson Mogens Nielsen

2. Vending Machine 1
Timed Automata

3. Vending Machine 1 Behaviour x time Timed Automata ord-cof cup del-cof30 20 10
ord-cof
cup
del-cof
time
Timed Automata

4. Vending Machine 2 Clocks -> Continuous Variables Hybrid Automata
Maler, Manna, Pnueli’91

5. Vending Machine 2 Clocks -> Continuous Variables Behaviour T,H t
100 50
ord-cof
cup
del-cof t
Hybrid Automata
Maler, Manna, Pnueli’91

6. Vending Machine 3 Linear Hybrid Automata
Alur, Courcouretis, Henzinger, Ho’93

7. Vending Machine 3 Behaviour T,H t HYTECH Linear Hybrid Automata
100 50
ord-cof
cup
del-cof t
HYTECH
Linear Hybrid Automata
Alur, Courcouretis, Henzinger, Ho’93

8. Symbolic Analysis PolyhedraT H

9. Symbolic Analysis PolyhedraT H

10. Symbolic Analysis PolyhedraT H

11. Symbolic Analysis PolyhedraT 
The exploration
may lead to generation
of infinitely many polyhedra
=>
No guarantee of termination H 
Manipulation of polyhedra inefficient!

12. TA’s versus LHA’s TOOLS Decidable Efficient Datastructure
UPPAAL, KRONOS,CMC,...
Decidable
Efficient Datastructure
DBM’s, NDD’s, CDD’s, ..
Expressiveness 
TOOLS
HYTECH, POLLUX,..
Undecidability
Datastructures
Plyhedra
Expressiveness       
STOPWATCH AUTOMATA
x’==0 or x’==1

13. STOPWATCH AUTOMATA Extension of UPPAAL to SWA
Cassez, Larsen, CONCUR’00
Extension of UPPAAL to SWA
Reuse of efficient datastructures
Overapproximation
Every LHA may be translated into a SWA
APPLICATIONS
Scheduler
Gasburner
Water Level Control

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