Leveraging Modelica & FMI in Scilab open-source engineering software

1. Leveraging Modelica & FMI in
Scilab open-source engineering software
September 2015
1© Scilab Enterprises
Yann DEBRAY
: yann.debray@scilab-enterprises.com
: +33 1 80 77 04 73
: +49 157 51 49 49 15

2. Agenda
 Introduction
 Scilab Use cases
 Modelica in Scilab/Xcos
 Scilab/Xcos FMI import/export
 Demonstrations
 Questions - Answers
2© Scilab Enterprises

3. Introduction
Scilab History
Scilab Today
Scilab Distribution
3© Scilab Enterprises

4. Scilab History
1980:
First Scilab
Kernel
= Free Matlab
1990 - 2003:
1994: Scilab
freely distributed
on the net
2003 - 2012:
Scilab
Consortium
2012 - Today:
Scilab
Enterprises
drives the
evolution of
Scilab
4
1980 – 1990:
INRIA – French national
research institute for
Informatics & Automation
Integration of Modelica
Since 2005
© Scilab Enterprises

5. Scilab Today
From www.scilab.org
 ~ 100 000 monthly installations from 150 countries
5© Scilab Enterprises

6. Scilab Open Source Distribution
Workstation Software:
 Scilab
Powerful Computation Engine
 Xcos
Dynamic Systems Modelling and Simulation
Server Software:
 ATOMS Server
Modules/Toolboxes Management
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7. Scilab Use cases
Main references
Industrial use cases
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8. Main Scilab References
 Aerospace & Defense:
CNES, Astrium, DLR, Safran, Dassault Aviation, DGA, Thales
 Automotive:
PSA, Renault, Leoni, Valeo, Faurecia, TMD Friction, Continental
 Metallurgy:
ArcelorMittal, Aperam, Alcan, Eramet
 Energy:
CEA, EDF, RTE, ABB, Total, IFP, Alstom…
 Chemical & Pharmaceutical :
Solvay/Rhodia, Sanofi
8© Scilab Enterprises

9. From R&D to industrial implementation
Execution Engine (based on Scilab)
9
Components from the
Model Repository …
… for simulation
… in dedicated
applications
Can be used …
© Scilab Enterprises 9

10. Modelling of a metallurgical reactor
 Use of odedc (discrete/continuous
ordinary differential equations solver)
© Scilab Enterprises 10

11. Live Monitoring of Air Handling Units
 Problem: Heating,
Ventilation, Air
Climatisation amounts to
60 % of energy bill =
500k€/year
 oscillations in Air Handling
Units control
(blue= cooling valve,
red= heating valve)
Scilab Solutions:
 Energy simulation
OPTICLIM (+Excel import)
 Energy monitoring
Modbus over TCP/IP
© Scilab Enterprises 11

12. Thermal pre-dimensioning of electronic
circuit based on Thermal Impedance
 Goal: Dimension quickly but with enough precision in an early phase
Results: Errors limited to about 3°C
Blue = « 0D » Model /
Red = CFD Simulations
3 observed points (the 3
junction temperatures)
12© Scilab Enterprises

13. Post-treatment tools from aero-acoustic data
 Thin band spectrum  cartographic 2D
 Data acquisition (30 GB per test campaign)
 Convertion into spectral data
(Fourier transform)
 Grid definition
 Correction matrix
 Display
13Fast processing and visualization
© Scilab Enterprises

14. DoE, post-processing and visualization
Modules used
 DACE (ATOMS): kriging
 NSGA2 : multi-objective
optimization
 TOPSIS : multicriteria decision
making (specific development)
Development of a GUI to explore
simulation results (Excel imported)
GUI, graphics, advanced mathematics
© Scilab Enterprises 14

15. Sizelab: Application
for mechanical pre-sizing
15© Scilab Enterprises 15

16. Scilab used for the mission ROSETTA
 Reading/writing
inputs/outputs data of Flight
Dynamics System (proprietary)
 Mission frames transformation
 Comets environments
 Comets topography and
Digital Terrain Model
 Statistic and probability
analysis
 Geometry computations
16
© Scilab Enterprises

17. Scilab/Xcos + Modelica/FMI
Scilab / Xcos functional coverage
Modelica in Xcos
FMI: Model-Exchange & Co-simulation
17© Scilab Enterprises

18. © Scilab Enterprises 18
 Mathematics
 Statistics
 Optimization
 Signal Processing
 Control Systems
A powerful platform with more than 2,000 functions:

19. Scilab Architecture
19
Scilab
Hardware adaptation
File
types
support
Graphical
Modelling &
Simulation Xcos
Maths functions
d/dt
aX²
+bX
Scientific functions
Stats
Fftw +Signal
processing
Optim
User interfaces
Command line Graphing Editor
APIs/extensions:
Language binding
Dynamic link
functions
Editor Scinote
HMI/ GUI Builder
Call_scilab
ATOMS Module
definition
Sparse
Matrix
interp
olation
Rand
-lib
Language interpreter
AST Types, integer, string, sparse time
Matlab compatibility
compatibility conversion
Development environments
help
Localization
Preferences
Windows_tools
elementary_functions
Control
systems

20. Xcos: Hybrid Dynamic Systems Modeler & Simulator
Xcos features
Graphical
Output
Graphical
Editor
Hybrid
Simulation
Customizable
Palettes
Multiphysics
simulation
Simulation
Acceleration
Xcos external modules
Finite State
Machine
Embedded Code
Generation
Functional
Mockup
Interface
20© Scilab Enterprises

21. © Scilab Enterprises 21
Discrete Simulation
 The observation of a phenomenon is
activated by an event. During the
activation, the state of the system
changes et programs future events.
Continuous Simulation
 Observation of a phenomenon
during a fixed and regular step time.
Hybrid Simulation
 The observation of a phenomenon
is made during a fixed time step, but
can also be activated by an event.

22. Model building in Xcos
© Scilab Enterprises 22
To compute and plot
the values of I1 and I2:
We obtain that:

23. Modelica integration in Xcos
© Scilab Enterprises 23
Real life
Xcos and Modelica

24. © Scilab Enterprises 24
Xcos standard causal blocks
 Equation:
 Block: written in C, Scilab language
𝑦 = 𝑓 𝑢
 Equation:
 Block: written in Modelica language
Xcos acausal blocks
𝑓 𝑦, 𝑢 = 0

25. How does it work?
© Scilab Enterprises 25
Modelica compiler embedded into
Xcos
1. Flattening process
2. Solution of the DAE and
generation of an equivalent
simulation function in C
(causal): the implicit subset is
replaced par an equivalent
superblock for the simulation
3. Compilation and dynamic
linking to Scilab

26. Conclusion: Scilab+Xcos+Modelica
--> mixed Xcos/Modelica modelling
--> Integrated graphical environnement in a powerful pre-/post-processing engine: Scilab!
Modelica compiler written in Ocaml
support only a subset of Modelica 2.0
--> Help us integrate the
OpenModelica Compiler

27. FMI: Model-Exchange & Co-simulation
Scilab/Xcos
Control team
Software A
Thermal team
FMU
import/export
--> Separate the model authoring tool from the model execution tool
--> Deploy from few simulation specialists to designers, domain specialists, …

28. Demonstrations
Automotive suspension with Scilab / Xcos / Modelica
FMI in Xcos
Xcos Parameter identification with fminsearch
Datafitting with Excel data
Xcos solvers
28© Scilab Enterprises

29. Three ways for Physical modelling with Scilab/Xcos
1. Scilab: Simple mathematical description with Ordinary
Differential Equations
2. Xcos: Causal description with transfert functions
3. Coselica: Acausal description with multi-physical block
example: Automobile suspension
© Scilab Enterprises 29

30. Ordinary Differential Equations (ODE) in Scilab
function yp=quarter_car_ode(t, y)
v = 4; // Speed [m/s]
m = 50;
c_F = 10000; // [N/m]
c_D = 400; // [Ns/m]
x = v*t ;
yp = [y(2);
1/m*(c_D*(v*zp-y(2))+c_F*(z-y(1)))];
endfunction
t = linspace(t0,t1);
y= ode("rkf",[0;0],t0,t,quarter_car_ode);
© Scilab Enterprises 30

31. Causal design with Xcos:
Automotive suspension from PSA
© Scilab Enterprises 31

32. Acausal with Modelica blockset in Xcos
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33. Demo Xcos FMI Cruise Control
33© Scilab Enterprises
• Modelled in SCADE Simulated in Xcos
--> Link to established specialized proprietary software

34. Demo Xcos FMI PID Controller
34© Scilab Enterprises
• The same PID Controller natively and imported with
model-exchange and co-simulation:
--> Fidelity in simulation, ease to model

35. Xcos Parameter identification
with fminsearch
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36. Datafitting with Excel data
36© Scilab Enterprises

37. Xcos solvers
37© Scilab Enterprises

38. Conclusion
 Scilab/Xcos + Modelica/FMI =
– Advanced simulation technologies, with the strength of
having a powerful computation platform
– Committed to open standards
– Let us do more in this direction together
Adopt Scilab, choose the open source
© Scilab Enterprises 38