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
Publicerad: 2013-03-27
ISBN: 978-91-7519-621-3 (print)
ISSN: 1650-3686 (tryckt), 1650-3740 (online)
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.
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