Toward

1
Toward Online Hybrid Systems Model Checking of Cy
ber-Physical Systems Time-Bounded Short-Run Behavi
orLei Bu, Qixin Wang, Xin Chen, Linzhang
Wang, Tian Zhang, Jianhua Zhao, and Xuandong
Li Nanjing University, The Hong Kong
Polytechnic University buleichenxinlzwan
gztluckzhaojhlxd_at_nju.edu.cn,
csqwang_at_comp.polyu.edu.hk
1. Demand Verification of Cyber-Physical
Systems Case 1 Train Control
System Case 2 Laser
Tracheotomy MDPnP
Safety Rule No Collision During Emergent
Braking! Safety Rule Cannot Start Laser
Scalpel

and Ventilator At The Same Time !
2. Modeling Language
Continuous Real-time Behavior
Discrete Control Modes
Hybrid Automata
3. Offline Modeling Verification? Case 1 Train
Control System Case 2 Laser
Tracheotomy MDPnP
Problem
Difficult To Verify Composed System State
Space Explosion Nonlinear Function
High Complexity
Difficult To Model Nondeterministic
Bahavior Runtime Parameter Wind Speed, Railway
Condition for Train control System, SpO2 for
MDPnP are collected online, cannot predict the
complete behavior space offline
1.Train communicate with RBC for new MA every
500ms. 2.If a train touches SBD point, brake
normally. 3.If a train have not get any info in
5s, brake emergently!
1.SpO2 sampling period 1 second 2. Other
automata are omitted from this poster due to
space limit
4. Online Modeling Verification

Case 1 Train Control System
Case 2 Laser Tracheotomy MDPnP
Procedure Runtime Control Parameters Become
Fixed Numeric Values
Time-bounded Short Run
Behavior
Scenario-Based Time-bounded Static Model Fast
Online Verification Before Model Expire

Hooray, No Nondeterministic! Small State space!
No need to build model for RBC!

The System to verify has only 3
trains,

Verified by BACH,

Only 58 msltlt500ms!
Verified By PHAVer,


Only 0.27 seconds
lt 1 second