www.into-cps.au.dk

ConsideringAbstractionLevelsonaCaseStudy

CasperThule&RenéNilsson

2016-11-07

• Introduction• Modeldescription• Modelabstraction• Results• INTO-CPS• Conclusion• Futurework

2ConsideringAbstractionLevelsonaCaseStudy

Agenda

• Introduction• Modeldescription• Modelabstraction• Results• INTO-CPS• Conclusion• Futurework

3ConsideringAbstractionLevelsonaCaseStudy

Agenda

• Cyber-physicalSystems– Interactionbetweencyberpartsandphysicalentities.E.g.aUAV

– Complexityischallenging

• Co-simulation– Modelsofconstituent components– DiscreteEventandContinuousTime

• Technologies– Crescendo– INTO-CPS

• Goal

4ConsideringAbstractionLevelsonaCaseStudy

Introduction

• CTmodel– NopriorknowledgeofUAVdynamics– Abstractmodeling– Modelrefinement

5ConsideringAbstractionLevelsonaCaseStudy

History

• DEmodel– APM:Copter– Reverseengineering

6ConsideringAbstractionLevelsonaCaseStudy

History

• Introduction• Modeldescription• Modelabstraction• Results• INTO-CPS• Conclusion• Futurework

7ConsideringAbstractionLevelsonaCaseStudy

Agenda

• Blockdiagramsanddifferential equations in20-sim

8ConsideringAbstractionLevelsonaCaseStudy

CTModel

• APM:Copter reverse engineering• ModeledwithVDM-RT

9ConsideringAbstractionLevelsonaCaseStudy

DEModel

• Introduction• Modeldescription• Modelabstraction• Results• INTO-CPS• Conclusion• Futurework

10ConsideringAbstractionLevelsonaCaseStudy

Agenda

• Hardware

• Controlflow

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BasicsofaUAV

Sensors

GyroscopeAccelerometer

BarometerGPS

Magnetometer

<<Actuator>>Motor(s)

SensorInput SensorFusion

FlightModePosition,velocity MotorController

Roll,pitch,yaw,velocity

Pilot Waypoint

Motor(s)

Throttle

• Waypoint

• Abstractedcontrolmodels(P&PID)

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Abstraction

GPS SF_GPS MotorControllerFlightController

Motor

UAV

PositionControl

P/PIDController

• Introduction• Modeldescription• Modelabstraction• Results• INTO-CPS• Conclusion• Futurework

13ConsideringAbstractionLevelsonaCaseStudy

Agenda

• Co-simulationresults.– Goal:3,2and4meters

• Totalerror

3.364.9

4.98

-0.16

1.7

0.55

5.36

5.75

7.3

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Results

P PID Original

~6.78 meters ~3.34 meters ~3.89 meters

• 6hourstocreateabstractions– files/LinesofCode

• High-levelbehaviorvslowleveldetails

• Breadthapproach

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Reflection

<<SensorFusion>>GPS

Position,velocity <<FlightMode>>Waypoint

Refinement

<<SensorFusion>>GPS,Accelerometer,

Gyroscope,Barometer,

Magnetometer

Position,velocity

Breadth Depth

P PID Original12/307 12/333 42/2270

• Introduction• Modeldescription• Modelabstraction• Results• INTO-CPS• Conclusion• Futurework

16ConsideringAbstractionLevelsonaCaseStudy

Agenda

• Tools• Functionality

• Maxdiff:11.8cm

17ConsideringAbstractionLevelsonaCaseStudy

INTO-CPS

• Introduction• Modeldescription• Modelabstraction• Results• INTO-CPS• Conclusion• Futurework

18ConsideringAbstractionLevelsonaCaseStudy

Agenda

• Abstractionusefulforprototyping– Gaininsight– Handlecomplexity– 6hours– Different expertises

• TransitiontoINTO-CPStechnology– Only interfacevariablechanges

19ConsideringAbstractionLevelsonaCaseStudy

Conclusion

• Introduction• Modeldescription• Modelabstraction• Results• INTO-CPS• Conclusion• Futurework

20ConsideringAbstractionLevelsonaCaseStudy

Agenda

• Utilize additional INTO-CPSfeatures– DesignSpaceExploration– Hardware-In-the-Loopsimulation– Software-In-the-Loopsimulation

• Generic componentsforOverture– Vector,controllers,driversetc.– Improvetoolsupport,reducedevelopmenttime

• Futurecasestudy– Battery management– Very low abstraction level

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FutureWork

”Thepurposeofabstraction isnottobe vague,buttocreate anewsemantic level inwhich

one can be absolutely precise”

- Edsger W.Dijkstra

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