• Defining Design Intent
• Defining Preliminary Product Structure
• Introducing Skeleton Models
• Communicating Design Intent
• Continued Population of the Assembly
• Managing Part Interdependencies
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Step 1 - Defining Design Intent
All products are designed with some preliminary planning. Sketches, ideas, proposals and specifications may exist to define the products’
purpose, function and design. This planning helps the designer understand the product better and start the design of the system and/or detailed
components. The designer can leverage this information to begin defining the structure of the design and detailed requirements of individual
components within Pro/ENGINEER.
Step 2 - Defining Preliminary Product Structure
The product structure consists of a list of components and their hierarchy within the assembly design. Many of the major subsystems required for the design will be determined when defining design intent.
The product structure can be created easily in Pro/ENGINEER allowing the creation of subassemblies and parts without having to create any geometry. Existing subassemblies and parts can also be added to the product structure without actually having to be assembled.
Defining the preliminary product structure helps to organize the assembly design into manageable tasks that can be assigned to design teams or individual designers.
Step 3 - Skeleton Models
Skeleton models act as a 3-D layout of the assembly and may be used to represent space requirements, important mounting locations, and motion.
Also, they can be used to share design information between subsystems and act as a means to control the references (or interactions) between these subsystems. Skeleton models serve a variety of purposes defining form, fit, and function of an assembly. Some examples are:
• Space claim (form / fit)
• Component to component interface definition (fit)
• Motion representation (function) nova - HGP
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Step 4 - Communicating Design Intent
Top-level design information such as important mounting locations and space claim requirements can be placed in the top-level assembly skeleton model. This information then can be distributed to the appropriate
subassembly skeleton models as needed. This allows for each subassembly to contain a skeleton model with only the pertinent design information for that subassembly. This means that the subassembly design team can work confidently on their own design since they have local access to the top- level design criteria.
Consequently, many separate design teams can be working on their subassembly and referencing the same top-level design information. The result is an assembly developed concurrently that fits together the first time.
The recommended Pro/ENGINEER tool for storing design intent at different levels of the product structure is the skeleton model. Various data-sharing features such as Copy Geometry and Shrinkwrap can be used to communicate and propagate the design intent from level to level and from model to model.
Step 5 - Continued Population of the Assembly
Once the skeletal representation of the assembly has been defined, and the top-level design criteria have been distributed, individual component design can begin.
Many methods exist for populating the assembly structure with detailed parts. Existing components can be assembled, or components can be created in the context of the assembly. These individual parts can be related to each other using other functionality such as assembly relations, skeleton models, layouts, and merge features to further capture design intentions.
Step 6 - Managing Part Interdependencies
One of the greatest benefits of parametric modeling is the ease with which designs can be changed. Methods can be used to manage the many desired interdependencies between components of a design in an organized
manner. Managing interdependencies allows components from one design to be used in another and provides a means for controlled change and update of the entire assembly design.
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Tools exist in Pro/ENGINEER to help guide users in setting up the dependencies between parts and subassemblies that will propagate the desired changes throughout the entire design. Reference control can be configured to limit undesired dependencies and allow desirable ones.
Furthermore, a Global Reference Viewer tool has been provided to help users investigate and understand existing interdependencies between components.
Note:
As the design evolves and the designers are able to obtain more information about the design, they may need to further define the design intent, edit the skeletons, pass the critical data to other models and continue to populate the assembly.
This is an iterative process—one in which the design becomes more detailed and specific throughout the project. You should, therefore, expect to perform the sequence of steps listed above more than once in order to complete the project.