Full System Simulation
Simulation of dynamic entities described by
differential algebraic equations in systems
that contain interacting parts from a variety
of physical disciplines.
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A
B
A
B
C
D
C
D
duration=%duration
F2
Reference
R=%R
R=%R
R1
R2
R3
C2
k=%k
C=%C
C=%C
C1
Plant
R=%R
B
A
D
C
%name=%V
EMF1
CV1
F1
R=%R
R5
NPN1
%name=%c
NPN2
Ground1
J=%J
J=%J
d=%d
Axis1
SpringDamper1
Axis2
J=%J
ratio=%ratio
Planetary
Axis3
Brake1
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Why Full System Simulation?
• Next step in the evolution of complex and advanced product
development
– There is a need to “lift” modeling and simulation
closer to the real product
• Some optimization is only achievable at a system level
• Some errors are only visible at a system level
• Design of advanced product behavior is a collaborative
process that needs means for communication
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Multi-disciplinary Modeling
• Electronics
– Semi-conductors
– Power electronics
– Electrical Machines
• Thermodynamics
– Combustion
– Gas and fluid flow
– Thermal
• Mechanics
– Rotational
– Translational
– Multi-body systems
• Hydraulics
• Control Systems
In many cases models in
these areas can be built
using a lumped approach!
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Existing options for
Full Systems Modeling and Simulation
Block Diagram
Programming in ADA or Fortran
or Co-Simulation ...
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What if Full System Modeling and
Simulation was as Simple as This?
Servo example
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Old Modeling Paradigm
• Input/output blocks or functions
– Signal based thinking (assignments: u:=R*i, i:=u/R?)
• Blocks that correspond to mathematical operations
– Integrators, scaling, summation,…
• Plain numerics
– No structural code optimization possible
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Block Diagram
Causal Modeling
• Manual manipulation of formulas
– Linear equation solving and differentiation
• Choice of I/O is fixed from start
– Remodeling needed for other purposes
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New Modeling Paradigm
• Component based modeling
– Focus on physical connections (equations: u=R*i)
• Components that correspond to physical objects
– Resistors, inductors, shafts, joints, …
– I/O blocks are specializations
• Numerics and symbolics
– Symbolic preprocessing (sorting and simplifying
equations)
– Structural optimization and code generation (efficiency)
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Component Diagram
Acausal Modeling
• Equations is “stored” in the components
– No manual manipulation involved
– Focus on topology
• Choice of I/O at end of modeling process
– Reuse of model for different purposes
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Comparison with Block Oriented Modeling
Only occasional correspondence between physical component and block!
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