Integration with Other Applications > Managing CAD and Part Structures in Windchill > Introduction and Methodology Overview
  
Introduction and Methodology Overview
The process of designing products and managing product data using Windchill requires the use of specific design methodologies and techniques. The methodology employed usually depends on the physical size and complexity of the product being developed as well as both the size and geographic organization of the enterprise involved. The following product design methodologies and techniques are currently supported in Windchill.
CAD-driven Design
CAD-driven (bottom-up) design is the traditional methodology used to create a product structure and has been a mainstay for product data management using Windchill. Using this approach, the design process begins in the CAD authoring environment with the definition of detail geometry as well as design and placement constraints for component parts and subassemblies. Once completed, the CAD assembly structure is checked into the Windchill database to generate an analogous enterprise “part” structure. This action also links the two structures together for the continual exchange of information, for example, attribute values and visual representations. The relationship created between the CAD structure and the part structure is known as “association”. If the context of the association is defined as the strongest type (owner), CAD designers are able to update (build) the part structure with each check in of a modified CAD structure and enable data sharing across the enterprise.
For more information, see Sample CAD-driven Methodology Flow.
Top-down Design
Top-down design is a methodology best practice typically used for creating large multidisciplinary product assemblies. Using this approach, Product Architects are able to begin the design process in Windchill and share the design with other teams across the enterprise, enabling design concurrency. One of the many benefits of this approach is that a high-level product structure framework can be created using product assembly templates, without the immediate need to define geometry or place components. Tasks can be delegated to members of design teams that are geographically dispersed across the enterprise. For example, one team can define footprint or spatial constraints while another team assigns non-geometric product information such as part number, cost, supplier, material, and so on. Once the product structure framework has been fully reviewed and approved, the various subassemblies of the framework can then be passed on to CAD teams for detail geometry definition and product assembly build out.
For more information, see Sample Top-down Methodology Flow.
Design-in-Context
Viewing all of the components of a large CAD assembly while you modify only a few can be data intensive, time consuming, and visually confusing. In these situations, it is more efficient to reference and modify only those portions of a CAD assembly that are relevant to the design task at hand. Design-in-context is a special Windchill technique that enables you to effectively filter a very large product structure and reduce it to a selection of components. For example, you can filter parts based on product option criteria (LE and LX, but not SE vehicle options). You can also filter parts using volumetric and spatial criteria (box, sphere, and proximity). For example, everything within two feet of the engine block. By drilling down to specific assemblies or parts located within your “work zone”, you can preview and verify this lightweight context in Windchill using Creo View and then open it in your CAD authoring application to complete your design task quickly, with less clutter and more clarity.
For more information, see Design in Context Flow.