Multi-domain modelling for complex mechanisms
The multi-domain modelling capability and modelling methodology used in Dymola is very well adapted to the design of complex mechanisms. Utilising the Modelica Multibody library a detailed model of the mechanical parts of a mechanism can be constructed and then used to perform different types of analysis depending on the design phase. For instance, early in the design process we could use the model to size the actuators by defining the speed at which the mechanism must move, later in the design process we can reuse the same mechanical model to test out the performance of the chosen actuator. This ability to reuse the same model for different analysis saves time and provides a good way to test that the selected actuator meets the specification.
An example of this type of application is an aircraft business class seat that folds down to be a fully flat bed. At the start of the design process we have targets defined for how quickly the seat should move between the two conditions and we have defined load cases for the passenger weight. Using this information and the geometry of the seat we can build a model in Dymola that calculates the force required at the actuator to meet the targets. We can also use the model to explore how the required actuator force is affected by geometry changes or different passenger sizes.
Later in the design process once the actuator and seat control system have been developed we can connect these to our mechanical model of the seat mechanism and investigate their performance to see if they meet the targets. Reusing the original mechanical model saves time and allows the actuator to be tested using the same model that was used to determine the specification.
Aerospace
