Modelling approach for the simulation-based preliminary design of power transmissions

The promises of Model-Based Design have led to the development of numerous methodologies and software tools, especially for the specific or detailed design stages, from controller design to finite element analysis. However, the Model-Based Design of actuation systems lacks methodologies and expressive simulation models that are suited to preliminary design, where key technical decisions are taken considering various design alternatives and few available design details. In order to fill this gap, the present paper illustrates how scaling laws and acausal modelling can be used as a design tool, exploiting inverse simulation capabilities to evaluate technological alternatives quantitatively from limited design detail information. The application of the modelling approach is shown for two major components of mechanical transmission systems: roller bearings and ball and roller screws. The scaling laws presented are validated with manufacturers’ data. To conclude, the suitability of the proposed methodology is illustrated with the preliminary sizing of an electromechanical actuator for an aircraft primary flight control surface (aileron).