Publicerad: 2008-07-02
ISBN: 978-91-7519-823-1
ISSN: 1650-3686 (tryckt), 1650-3740 (online)
Modelica specifies two types of equations: the equations defined directly in the “equation” section; which are supposed to hold all the time; and the equations defined within a “when” statement. The latter are “activated” by explicit events at corresponding times. In making the analogy with Scicos; the equations of the first type are the counterpart of “always active” blocks whereas the second type equations are “event activated” blocks. A useful feature in Scicos is the mechanism of activation inheritance. In this paper; we examine the possible extension of the Modelica specification to introduce a similar mechanism in Modelica.
[1] M. Otter; H. Elmqvist; S. E. Mattsson; “Hybrid Modeling in Modelica based on the Synchronous Data Flow Principle”; CACSD’99; Aug; 1999; Hawaii; USA.
[2] Modelica Association; Modelica® - A Unified Object- Oriented Language for Physical Systems Modeling; www.modelica.org/documents/ModelicaSpec30.
[3] A. Benveniste; P. Le Guernic; C. Jacquemot.;"Synchronous programming with events and relations : the Signal language and its semantics"; Science of Computer Programming; 16; 1991; p. 103-149.
[4] R. Nikoukhah; “Extensions to Modelica for efficient code generation and separate compilation”; in Proc. EOOLT Workshop at ECOOP’07; Berlin; 2007.
[5] R. Nikoukhah; “Hybrid dynamics in Modelica: Should all events be considered synchronous”; in Proc. EOOLT Workshop at ECOOP’07; Berlin; 2007.
[6] R. Nikoukhah; S. Furic; “Synchronous and Asynchronous Events in Modelica: Proposal for an Improved Hybrid Model”; in Proc. Modelica Conference; Bielefeld; 2008.
[7] P. Fritzson - “Principles of Object-Oriented Modeling and Simulation with Modelica 2.1”; Wiley-IEEE Press; 2003.
[8] S. L. Campbell; Jean-Philippe Chancelier and Ramine Nikoukhah; “Modeling and Simulation in Scilab/Scicos”; Springer; 2005.
