Konferensartikel

Tool Demonstration Abstract: OpenModelica and CasADi for Model-Based Dynamic Optimization

Alachew Shitahun
Department of Computer and Information Science, Linkoping University, Sweden

Vitalij Ruge
Department of Mathematics and Engineering, University of Applied Sciences, Germany

Mahder Gebremedhin
Department of Computer and Information Science, Linkoping University, Sweden

Bernhard Bachmann
Department of Mathematics and Engineering, University of Applied Sciences, Germany

Lars Eriksson
Department of Electrical Engineering, Linköping University, Sweden

Joel Andersson
Department of Electrical Engineering and Optimization in Engineering Center (OPTEC), K.U. Leuven, Belgium

Moritz Diehl
Department of Electrical Engineering and Optimization in Engineering Center (OPTEC), K.U. Leuven, Belgium

Peter Fritzson
Department of Computer and Information Science, Linkoping University, Sweden

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Ingår i: Proceedings of the 5th International Workshop on Equation-Based Object-Oriented Modeling Languages and Tools; April 19; University of Nottingham; Nottingham; UK

Linköping Electronic Conference Proceedings 84:12, s. 107-108

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Publicerad: 2013-03-27

ISBN: 978-91-7519-621-3 (print)

ISSN: 1650-3686 (tryckt), 1650-3740 (online)

Abstract

This paper demonstrates model-based dynamic optimization through the coupling of two open source tools: OpenModelica; which is a Modelica-based modeling and simulation platform; and CasADi; a framework for numerical optimization. The coupling uses a standardized XML format for exchange of differentialalgebraic equations (DAE) models. OpenModelica supports export of models written in Modelica and the Optimica language extension using this XML format; while CasADi supports import of models represented in this format. This allows users to define optimal control problems (OCP) using Modelica and Optimica specifications; and solve the underlying model formulation using a range of optimization methods; including direct collocation and direct multiple shooting. The proposed solution has been tested on several industrially relevant optimal control problems; including a diesel-electric power train; a free-floating robot; and a stirred-tank.

Nyckelord

Model-Based Optimization; OpenModelica; Dynamic Optimization; Modelica; CasADi

Referenser

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