7. SUMMARY AND CONCLUSIONS
When a clutch is used in a propulsion system, discontinuities occur in the describing model. This leads to some challenging problems when performing computer simulations. The two main difficulties are numerical stiffness and changing model structure. In this paper is presented the bond graph method as a modelling framework and a clutch model which allows a constant model structure and minimizes the stiffness problem.
Simulation results from an example system using the presented clutch model, is also presented. These results indicated the usefulness of computer simulation in design analysis.
 Breedveld, P.C., Rosenberg, R.C, and Zhou T.
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