1. GM-CMU Collaborative Research Laboratory Temporal Logics for Analyzing Hybrid Systems Simulation Traces

2. GM-CMU Collaborative Research Laboratory Sources of Simulation Traces VehicleSim : A software simulator for vehicle dynamics Simulation Traces from MATLAB / Simulink Physical testing of vehicles on roads Hybrid Systems Visual Tools: Ptolemy (Berkeley), CHARON (UPenn) VehicleSim Simulator MATLAB Simulink Physical Simulation Visual Tools PTOLEMY CHARON

3. GM-CMU Collaborative Research Laboratory Temporal Logic We can define “interesting” events and sequence of events. – Event a does not ever happen before event b – Event a is eventually followed by event b – Event a is always accompanied by event b – Event a follows event b within two time steps. Forces definition of formal correctness properties – Easier-to-use sugar-coated versions like Intel’s FORSPEC

4. GM-CMU Collaborative Research Laboratory Overall System Design VehicleSim Simulator MATLAB Simulink Physical Simulation Visual Tools PTOLEMY CHARON Simulation Trace Temporal Property Automated Trace Analyzer Report

5. GM-CMU Collaborative Research Laboratory Example Always (a <= b) The value of a never exceeds the value of b. a <= b a > b ERROR

6. GM-CMU Collaborative Research Laboratory Example Always (a=b  X (c=100) ) If the value of a equals the value of b, then c must take the value 100 in 1 time step. True a = b c!=100 c=100 Trace: a b c 0 0 0 1 2 100 ERROR

7. GM-CMU Collaborative Research Laboratory Example Always (a=b  X (c=100) ) If the value of a equals the value of b, then c must take the value 100 in 1 time step. True a = b c!=100 c=100 Trace: a b c 0 0 0 1 2 100 ERROR

8. GM-CMU Collaborative Research Laboratory Example Always (a=b  X (c=100) ) If the value of a equals the value of b, then c must take the value 100 in 1 time step. True a = b c!=100 c=100 Trace: a b c 0 0 0 1 2 100 ERROR

9. GM-CMU Collaborative Research Laboratory Example Always (a=b  X (c=100) ) If the value of a equals the value of b, then c must take the value 100 in 1 time step. True a = b c!=100 c=100 Trace: a b c 0 0 0 1 2 99 ERROR

10. GM-CMU Collaborative Research Laboratory Example Always (a=b  X (c=100) ) If the value of a equals the value of b, then c must take the value 100 in 1 time step. True a = b c!=100 c=100 Trace: a b c 0 0 0 1 2 99 ERROR

11. GM-CMU Collaborative Research Laboratory Example Always (a=b  X (c=100) ) If the value of a equals the value of b, then c must take the value 100 in 1 time step. True a = b c!=100 c=100 Trace: a b c 0 0 0 1 2 99 ERROR

12. GM-CMU Collaborative Research Laboratory Research Questions How to capture the continuity of trace data ? How to capture the notion of continuous time? – Do we need a richer yet understandable logic in line with FORSPEC for Hybrid Systems? Online vs. Offline monitoring – If monitoring is offline, can we write efficient algorithms that can “look into the future”

13. GM-CMU Collaborative Research Laboratory Overall System Design VehicleSim Simulator MATLAB Simulink Physical Simulation Visual Tools PTOLEMY CHARON Simulation Trace Temporal Property Automated Trace Analyzer Report Your inputs?

14. GM-CMU Collaborative Research Laboratory

15. GM-CMU Collaborative Research Laboratory Robustness of Hybrid Systems and Simulation Traces If two traces have a prefix equivalent under a “robustness” assumption, we can combine them into an execution tree.