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instance may be accepted.

4.Repeat steps 1 to 3 for all other parts in the assembly.

5.Use the solid modeler to create the assembly instance using all the instances created in step 4. These instances are positioned relative to datums established by part features.

6.Check if the assembly instance from step 5 satisfies the design constraints. If yes, the assembly is accepted. If not, the assembly is rejected.

7.Repeat steps 1 to 6 as many times as the desired sample size (number of assembly instances) is used to calculate the statistics. The larger the sample size the better, and the more confidence we have in the results.

DC:19.3 ASSEMBLIES

•While assemblies apparently look simple, they pose intersection problems

•The dilemma is that two points in a modelled assembly may occupy the same point in space, a physical impossibility.

•In some cases this may be simply ignored, but when doing interference checks, or joining models, the two assembled parts may become one part, then change the results when doing FEM, kinematic, and vibration analysis.

•Some methods to deal with this are,

-Explicitly store, and manipulate parts of an assembly separately

-To use complex graphics boundaries called s-sets (still research)

DC:19.4 OPTIMIZATION

• One of the most important aspects of engineering

*************** Add in optimization notes