1. demand: verification of cyber-physical systems
DESCRIPTION
- PowerPoint PPT PresentationTRANSCRIPT
Toward Online Hybrid Systems Model Checking of Cyber-Physical Systems Time-Bounded Short-Run Behavior
Lei Bu*, Qixin Wang†, Xin Chen*, Linzhang Wang*, Tian Zhang*, Jianhua Zhao*, and Xuandong Li* *Nanjing University, †The Hong Kong Polytechnic University
{bulei|chenxin|lzwang|ztluck|zhaojh|lxd}@nju.edu.cn, [email protected]
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
Hybrid Automata
Discrete Control Modes
Continuous Real-time Behavior
3. Offline Modeling & Verification?Case 1: Train Control System Case 2: Laser Tracheotomy MDPnP Problem
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 second2. Other automata are omitted from this poster due to space limit
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
4. Online Modeling & Verification Case 1: Train Control System Case 2: Laser Tracheotomy MDPnPProcedure
Runtime Control Parameters
Become Fixed Numeric Values
Time-bounded Short Run Behavior
Scenario-Based Time-bounded Static Model
Fast Online Verification Before Model Expire
No need to build model for RBC!
The System to verify has only 3 trains,
Verified by BACH,
Only 58 ms<<500ms!
Verified By PHAVer,
Only 0.27 seconds < 1 second