Building and Compiling the Simcenter Amesim Model

Building the model

Compiling the model

When the Simcenter 3D Motion solver is started it loads a model dll of the Simcenter Amesim model. This dll must be created by the user inside Simcenter Amesim and then referenced from within Simcenter 3D Motion.

Procedure

1. The first step to linking the Simcenter 3D Motion model to the Simcenter Amesim model is to build a standard Simcenter Amesim model.

2. The next step in the process is to include the Simcenter 3D Motion block inside your Simcenter Amesim model. To create the Simcenter 3D Motion Mechatronics interface the user performs the following steps:Create Export Icon

   Go to Sketch mode.
   
   
   Select Interfaces > Create interface block >
    Simcenter 3D Motion (model exchange)
   
   
   Define inputs and outputs in the Interface Icon Creation dialog, see the figure below.
   

   Interface block

   Interface Icon The interface block represents the Simcenter 3D Motion mechanism inside Simcenter Amesim. The user should be aware of the input/outputs of this block since these become the connection control nodes in Simcenter 3D Motion. Figure 3: Define actuator and sensor channels

3. Connect the Interface Block to the Simcenter Amesim ModelThe next step is to connect the Simcenter 3D Motion Mechatronics interface block up to the rest of the Simcenter Amesim model as shown in the figure below.

   Figure 4: The Interface block connected to the Simcenter Amesim model

   The input and output channels on the Interface Block do not have a specific physical type: no units are defined nor physical magnitude. Simcenter Amesim modeling elements typically expect a certain magnitude on their inputs and outputs. Therefore, the user typically needs Simcenter Amesim force transducers and displacement or velocity convertors as shown in the Interface block connected to the Simcenter Amesim model.

   Insert a "Force transducer" from the Mechanical Library

   Two null to line displacement and velocity

   Insert two sign inverters for the Simcenter 3D Motion sensor values from the Signal, Controls Library

   Connect the building blocks

   Note

    MKS Units
   
   
    Units
   
   Simcenter Amesim uses MKS units. Make sure the Simcenter 3D Motion solver settings are set to MKS Units
   or
   convert the input and output control nodes before sending the signals to and from the Simcenter Amesim block.
   
   
   Take care with the sign conventions. Depending on the Simcenter 3D Motion element and Simcenter Amesim element connected through the interface block, the sign may have to be inverted.
   
   
   Scale factors and offsets are also available on the Simcenter 3D Motion side at each Control Input and Output, in order to avoid the need to modify the Simcenter Amesim model and to recompile it for testing purposes.
   

4. Compile the Simcenter Amesim ModelSetting up Simcenter Amesim models and running simulations is done using the different Simcenter Amesim modes.

   The 4 stages are:

   Sketch mode

   Submodel mode

   Parameter mode

   Simulation mode

   The Simcenter Amesim user uses these modes from left to right.

   Build the model in Sketch mode

   Go to Submodel mode, select Premier submodel

   Go to Simulation mode

   Simcenter Amesim now compiles the dll that Simcenter 3D Motion is going to use. This *.dll is created in the Simcenter Amesim working directory.

   Use Write files for simulation in the File menu.

   This creates a *.sim file in the working directory required by the Simcenter 3D Motion solver. Note In most cases, models containing interface blocks cannot be run as they are. However, it can be useful to perform some basic checks such as open-loop simulations to see if the configuration of your model is correct; for example to check whether it can locate all its resources (typically tables) and that it initializes correctly. See section Open-loop simulations for basic model checks for more detail on this topic.