Scicos

"Scicos is a graphical dynamical system modeler and simulator developed in the Metalau project at INRIA, Paris-Rocquencourt center. With Scicos, user can create block diagrams to model and simulate the dynamics of hybrid dynamical systems and compile models into executable code. Scicos is used for signal processing, systems control, queuing systems, and to study physical and biological systems. New extensions allow generation of component based modeling of electrical and hydraulic circuits using  the Modelica language.
 
The features are:

GUI and graphics

• GUI to model dynamical systems as block diagrams
• Palettes of standard blocks.
  One can:
  • Modify existing open source blocks
  • Program new blocks in C, Fortran (dynamic link), or Scilab
  • Extend current palettes
• Animation block
• Interfaces to Tcl/Tk widgets to generate custom GUIs

Hierarchical structures

• Model components can be aggregated into Super Blocks to create a hierarchical block diagram
• Converts independent Super Blocks into C code

Simulations

• Batch mode simulations from Scilab
• Powerful formalism to model hybrid systems, i.e., possibility to combine continuous and discrete-time behaviors in the same model
• Choice of solvers:
  • Ordinary Differential Equations (ODE) with SUNDIALS Solver CVODE.
  • Differential Algebraic Equations (DAE) with SUNDIALS Solver IDA.
• "Implicit" blocks based on differential algebraic equations can be created and processed by the DASKR solver

Compilation, debugging

• Compiles and runs simulations on block diagrams
• Performs partial recompilations to save time
• Interfaces with external programs and operating systems
• Adjustable debugging levels
• Breakpoint placement for debugging

Code generation

• Generates C code
• Generates real-time code for RTAI (see RTAI-Lab)

Interfaces

• Can be piloted from Scilab programs
• Data and state variables can easily be exchanged with external programs
• Interfaces to digital acquisition cards with Scicos-HIL (Linux and Windows) and Scicos-RTAI (Linux RTAI)
• Can integrate Modelica objects, for example to model electrical and hydraulic circuits

http://www.scicos.org/

http://scicoshdl.sourceforge.net/