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Simulation-based Test Case Generation
for Unmanned Aerial Vehicles
in the Neighborhood of Real Flights
IEEE International Conference on Software Testing, Verification and Validation (ICST) 2023
17 April 2023
Sajad
Khatiri
Sebastiano
Panichella
Paolo
Tonella
• `
Unmanned Aerial Vehicles (UAVs)
2
Field Testing
o Reliable
o Not Reproducible
o Limited Test Scenarios
o Expensive
o Time Consuming
o Unsafe
3
Simulation-based Testing
o Reproducible
o Scalable & Automatable
o Affordable
o Safe
o Reliable Test Results?
o Reproducing Real-world Bugs?
o Generating Realistic Test Cases?
4
5
Latest Github Issue Sample PX4 Flight Log
6
Latest Github Issue Sample PX4 Flight Log
How can PX4 developers use the log to fix the issue?
SURREALIST
Generate Realistic and Effective simulated test cases
1. Systematically Replicate Field Tests in simulation using flight logs
2. Systematically Generate Challenging, but similar test cases
7
UAV System Test
UAV Configurations
Autopilot Parameter
Config Files (mission plan)
Environment Configurations
Weather Condition
Surrounding Objects
Runtime Commands
Radio Controller Commands
Starting Mission
Expected Behavior
Flight Trajectory
Safety Requirements
8
1. Flight Replication
Systematically Replicate field tests in simulation
• Find optimal drone/environment configurations
• Replicate a Specific Logged Behavior
• Minimizing differences in real vs simulation records
9
UAV Config.
Env. Config.
Commands
Expectation
Replicated Test
Given the flight log of an autonomous real-world flight,
Can we place an obstacle in the simulation environment
to faithfully replicate the flight’s trajectory?
Evaluation Scenario
1. Flight Replication
10
3×3×3 box
Seed Solution
11
1. Flight Replication
Distance: DTW (Dynamic Time Warping)
Move (∆x, ∆y)
Resize (∆l, ∆w, ∆h)
Rotate (∆r)
Mutations
12
1. Flight Replication
Obstacle Move (∆y = +4)
Obstacle Move (∆y = -4)
Mutations
13
1. Flight Replication
Adapt the mutation
for next round
Mutations
Obstacle Move (∆y = +4)
14
1. Flight Replication
Final Solution
15
1. Flight Replication
Final Solution
16
o Obstacle was moved 2m up, rotated 30˚ and made 2.8m taller
o Almost identical replication of the flight trajectory
Main Findings
1. Flight Replication
2. Test Generation
Systematically Generate Challenging but similar test cases
• Manipulate drone/environment configurations
• According to a predefined Difficulty measure
17
UAV Config.
Env. Config.
Commands
Expectation
Generated Test
Given a simulated test case for autonomous UAV flight,
Can we generate test cases that violate safety distance
to obstacles by placing an additional obstacle?
18
2. Test Generation
Evaluation Scenario
Same size box
Seed Solution
d1
d2
Distance = 2×d1 + d2
19
2. Test Generation
Move (∆x, ∆y)
Obstacle Move (∆x = -8)
Obstacle Move (∆x = -4)
Mutations
20
2. Test Generation
Final Solution
21
2. Test Generation
Final Solution
22
o Obstacle was moved 8m to the left and 1m up
o Final test revealed a nondeterministic behavior
o A critical and reproducible bug in PX4 which leads to crashes
Main Findings
2. Test Generation
github.com/skhatiri/Surrealist
mazras@usi.ch
www.skhatiri.ir
Sajad Khatiri
23

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SURREALIST - ICST 2023

  • 1. Simulation-based Test Case Generation for Unmanned Aerial Vehicles in the Neighborhood of Real Flights IEEE International Conference on Software Testing, Verification and Validation (ICST) 2023 17 April 2023 Sajad Khatiri Sebastiano Panichella Paolo Tonella
  • 2. • ` Unmanned Aerial Vehicles (UAVs) 2
  • 3. Field Testing o Reliable o Not Reproducible o Limited Test Scenarios o Expensive o Time Consuming o Unsafe 3
  • 4. Simulation-based Testing o Reproducible o Scalable & Automatable o Affordable o Safe o Reliable Test Results? o Reproducing Real-world Bugs? o Generating Realistic Test Cases? 4
  • 5. 5 Latest Github Issue Sample PX4 Flight Log
  • 6. 6 Latest Github Issue Sample PX4 Flight Log How can PX4 developers use the log to fix the issue?
  • 7. SURREALIST Generate Realistic and Effective simulated test cases 1. Systematically Replicate Field Tests in simulation using flight logs 2. Systematically Generate Challenging, but similar test cases 7
  • 8. UAV System Test UAV Configurations Autopilot Parameter Config Files (mission plan) Environment Configurations Weather Condition Surrounding Objects Runtime Commands Radio Controller Commands Starting Mission Expected Behavior Flight Trajectory Safety Requirements 8
  • 9. 1. Flight Replication Systematically Replicate field tests in simulation • Find optimal drone/environment configurations • Replicate a Specific Logged Behavior • Minimizing differences in real vs simulation records 9 UAV Config. Env. Config. Commands Expectation Replicated Test
  • 10. Given the flight log of an autonomous real-world flight, Can we place an obstacle in the simulation environment to faithfully replicate the flight’s trajectory? Evaluation Scenario 1. Flight Replication 10
  • 11. 3×3×3 box Seed Solution 11 1. Flight Replication Distance: DTW (Dynamic Time Warping)
  • 12. Move (∆x, ∆y) Resize (∆l, ∆w, ∆h) Rotate (∆r) Mutations 12 1. Flight Replication
  • 13. Obstacle Move (∆y = +4) Obstacle Move (∆y = -4) Mutations 13 1. Flight Replication
  • 14. Adapt the mutation for next round Mutations Obstacle Move (∆y = +4) 14 1. Flight Replication
  • 16. Final Solution 16 o Obstacle was moved 2m up, rotated 30˚ and made 2.8m taller o Almost identical replication of the flight trajectory Main Findings 1. Flight Replication
  • 17. 2. Test Generation Systematically Generate Challenging but similar test cases • Manipulate drone/environment configurations • According to a predefined Difficulty measure 17 UAV Config. Env. Config. Commands Expectation Generated Test
  • 18. Given a simulated test case for autonomous UAV flight, Can we generate test cases that violate safety distance to obstacles by placing an additional obstacle? 18 2. Test Generation Evaluation Scenario
  • 19. Same size box Seed Solution d1 d2 Distance = 2×d1 + d2 19 2. Test Generation Move (∆x, ∆y)
  • 20. Obstacle Move (∆x = -8) Obstacle Move (∆x = -4) Mutations 20 2. Test Generation
  • 22. Final Solution 22 o Obstacle was moved 8m to the left and 1m up o Final test revealed a nondeterministic behavior o A critical and reproducible bug in PX4 which leads to crashes Main Findings 2. Test Generation