Session 6A - Interoperability

Title:	General Purpose Lua Interpreter for Modelica
Authors:	Fabian Buse and Tobias Bellmann
Abstract:	The application of simulation in the development of complex systems becomes more and more important. Modeled systems often are comprised of mechanical, electrical as well as software systems. It is usually not possible anymore to evaluate a systems performance without considering some higher level logic. Scripting languages such as Lua, are often well suited to implement these logic elements. This paper shows the integration of the Lua interpreter into Modelica, and gives examples how the library can be used to help with the simulation industrial robots or in the development of a planetary exploration rover in the MMX Mission.
Keywords:	Modelica, Lua, script language, robotics, finite state machine
Paper:	full paper
Bibtex:	@InProceedings{modelica.org:Buse:2021, title = "{General Purpose Lua Interpreter for Modelica}", author = {Fabian Buse and Tobias Bellmann}, pages = {425--431}, doi = {10.3384/ecp21181425}, booktitle = {Proceedings of the 14th International Modelica Conference}, location = {Link\"oping, Sweden}, editor = {Martin Sj\"olund and Lena Buffoni and Adrian Pop and Lennart Ochel}, isbn = {978-91-7929-027-6}, issn = {1650-3740}, month = sep, series = {Link\"oping Electronic Conference Proceedings}, number = {181}, publisher = {Modelica Association and Link\"oping University Electronic Press}, year = {2021} }

Title:	Object Manipulation and Assembly in Modelica
Authors:	Robert Reiser
Abstract:	This paper introduces a new library for the manipulation and assembly of 3D objects using Modelica. The method is based on collision detection, contact dynamics, position and orientation control as well as states for object manipulation. The aim is a stable and efficient simulation of these processes close to real physics. 3D objects (both elementary shapes and CAD objects) can be added from the library browser to a model by drag-and-drop and are directly capable of being manipulated by multiple grippers and conveyors or being assembled to an assembly. This allows a high degree of flexibility and the modeling effort can be decreased significantly.
Keywords:	manipulation, grasping, gripper, assembly, collision detection, contact dynamics, state machine
Paper:	full paper
Bibtex:	@InProceedings{modelica.org:Reiser:2021, title = "{Object Manipulation and Assembly in Modelica}", author = {Robert Reiser}, pages = {433--441}, doi = {10.3384/ecp21181433}, booktitle = {Proceedings of the 14th International Modelica Conference}, location = {Link\"oping, Sweden}, editor = {Martin Sj\"olund and Lena Buffoni and Adrian Pop and Lennart Ochel}, isbn = {978-91-7929-027-6}, issn = {1650-3740}, month = sep, series = {Link\"oping Electronic Conference Proceedings}, number = {181}, publisher = {Modelica Association and Link\"oping University Electronic Press}, year = {2021} }

Title:	A Portable and Secure Package Format for Executable Simulation Modules based on WebAssembly
Authors:	Moritz Allmaras, Andrés Botero Halblaub, Harald Held and Tim Schenk
Abstract:	We propose a new format (Digital Twin Assembly - dtasm) for self-contained executable co-simulation modules that is portable and sandboxed, yet offers performance close to native machine code and is sufficiently lightweight for running on embedded devices. Dtasm is based on WebAssembly, a standardized bytecode format for a stack-based virtual machine originally developed for high-performance computations in web browsers. A language-independent binary interface for such modules is described that is functionally comparable to FMI for co-simulation but not tied to a particular programming language. We discuss the benefits and drawbacks of this approach and how it can address some specific issues for executable simulation modules running in parallel to operation of real systems.
Keywords:	Simulation Modularization, Portability, Sandboxing, WebAssembly
Paper:	full paper
Bibtex:	@InProceedings{modelica.org:Allmaras:2021, title = "{A Portable and Secure Package Format for Executable Simulation Modules based on WebAssembly}", author = {Moritz Allmaras and Andr\'es Botero Halblaub and Harald Held and Tim Schenk}, pages = {443--452}, doi = {10.3384/ecp21181443}, booktitle = {Proceedings of the 14th International Modelica Conference}, location = {Link\"oping, Sweden}, editor = {Martin Sj\"olund and Lena Buffoni and Adrian Pop and Lennart Ochel}, isbn = {978-91-7929-027-6}, issn = {1650-3740}, month = sep, series = {Link\"oping Electronic Conference Proceedings}, number = {181}, publisher = {Modelica Association and Link\"oping University Electronic Press}, year = {2021} }

Title:	New Method to Perform Data Reconciliation with OpenModelica and ThermoSysPro
Authors:	Daniel Bouskela, Audrey Jardin, Arunkumar Palanisamy, Lennart Ochel and Adrian Pop
Abstract:	Data reconciliation aims at improving the accuracy of measurements by reducing the effect of random errors in the data. This is achieved by introducing redundancies on the measured quantities in the form of constraints based on fundamental physical laws such as mass, momentum and energy balance equations. These constraints are called the auxiliary conditions. Modelica is an equational language that was conceived to express models based on first principle physics for the purpose of behavioral simulation. This paper shows how to reuse such models for the purpose of data reconciliation. The novelty is to automatically extract the auxiliary conditions from the Modelica model. Then the reconciled values are computed using a least square method constrained by the auxiliary conditions, as specified by the VDI 2048 standard. The new method has been implemented in OpenModelica. A simple example built with ThermoSysPro illustrates the method in detail.
Keywords:	data reconciliation, Modelica, model reuse, cyber-physical systems, structural analysis
Paper:	full paper
Bibtex:	@InProceedings{modelica.org:Bouskela:2021, title = "{New Method to Perform Data Reconciliation with OpenModelica and ThermoSysPro}", author = {Daniel Bouskela and Audrey Jardin and Arunkumar Palanisamy and Lennart Ochel and Adrian Pop}, pages = {453--462}, doi = {10.3384/ecp21181453}, booktitle = {Proceedings of the 14th International Modelica Conference}, location = {Link\"oping, Sweden}, editor = {Martin Sj\"olund and Lena Buffoni and Adrian Pop and Lennart Ochel}, isbn = {978-91-7929-027-6}, issn = {1650-3740}, month = sep, series = {Link\"oping Electronic Conference Proceedings}, number = {181}, publisher = {Modelica Association and Link\"oping University Electronic Press}, year = {2021} }