Conference article

Modified Multiple Shooting Combined with Collocation Method in JModelica.org with Symbolic Calculations

Evgeny Lazutkin
Simulation and Optimal Processes Group, Institute for Automation and Systems Engineering, Technische Universität Ilmenau, Ilmenau, Germany.

Abebe Geletu
Simulation and Optimal Processes Group, Institute for Automation and Systems Engineering, Technische Universität Ilmenau, Ilmenau, Germany.

Siegbert Hopfgarten
Simulation and Optimal Processes Group, Institute for Automation and Systems Engineering, Technische Universität Ilmenau, Ilmenau, Germany.

Pu Li
Simulation and Optimal Processes Group, Institute for Automation and Systems Engineering, Technische Universität Ilmenau, Ilmenau, Germany.

Download articlehttp://dx.doi.org/10.3384/ecp14096999

Published in: Proceedings of the 10th International Modelica Conference; March 10-12; 2014; Lund; Sweden

Linköping Electronic Conference Proceedings 96:104, p. 999-1006

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Published: 2014-03-10

ISBN: 978-91-7519-380-9

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

Abstract

This paper presents an efficient and a novel implementation of a combined multiple shooting and collocation (CMSC) algorithm for the solution of nonlinear optimal control problems. The implemented algorithm is a modification of the approach proposed in [17; 18]. The new implementation is done under the JModelica.org framework along with CasADi and Ipopt. The framework uses a symbolic pre-calculation of functions and derivatives. Besides the integration of various components of JModelica.org; Ipopt; and CasADi; the implementation facilitates simpler modeling of optimal control problems along with a choice of options for various linear algebra algorithms. The paper gives a description of the algorithm and elaborates the components of the framework. Numerical experimentations show that the new implementation is efficient in comparison with the published results of other authors.

Keywords

Nonlinear Optimal Control; Symbolic Automatic Differentiation; Nonlinear Programming; Multiple Shooting; Collocation

References

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