Creo Simulate > Getting Started with Creo Simulate > Planning and Modeling Considerations > Building Part and Assemblies > Planning for Shape Changes > Planning for Shape Changes
  
Planning for Shape Changes
The intent of Creo Simulate optimization is to redesign a part so that it better meets your design goals. To achieve this purpose, Creo Simulate changes the shape and size of the part’s features according to your instructions.
The aspects of the part that Creo Simulate changes are known as design variables. A design variable is a dimension or property that you direct Creo Simulate to alter within a specified range for the purpose of a sensitivity or optimization study. You can also use design variables in a standard design study to achieve a single-point solution. In this case, however, you change the design variable to a specific setting rather than allow it to move through a range of settings.
As an example, before you optimize a model, you can designate the position of a hole as a design variable or a set of design variables. You can then specify the optimization study so that Creo Simulate moves the hole until it finds a new location that minimizes stress in the model.
When you design a part for use with Creo Simulate, always think ahead and consider how you want the part’s features to move. Decide in advance which aspects of your part you want to define as design variables and what the parameter ranges might be. As you build the part, ensure that the movement of these features is not artificially restrained by relationships, topology, and so forth.
Here are some techniques you can consider:
Plan your shape changes and develop your part to allow these changes.
Build larger, more basic features first.
Identify relationships that prevent desired movement or cause undesired movement.
Change dimension names for easy identification.
Avoid topology conflicts introduced by design variable ranges and part building techniques that create interference between features or introduce extreme topological changes.
Return to Planning and Building Parts and Assemblies.