Ahmet Alp Gündüz - 030060034 - 1st Week

Conceptual design:

After completing the task clarification phase, the conceptual design phase determines

the principle solution. This is achieved by abstracting the essential problems,

establishing function structures, searching for suitable working principles

and then combining those principles into a working structure. Conceptual design

results in the specification of a principle solution (concept).

(Engineering Design A Systematic Approach; G. Pahl, W. Beitz; Page: 131 )

Layout Design:

The overall layout design, developed from the function structure, determines the

division of a product into assemblies and components and:

• identifies the source of the components; that is, whether they are in-house,

bought-out, standard or repeat parts

• determines the production procedure; for instance whether the parallel production

of individual components or assemblies is possible

• establishes the dimensions and the approximate batch sizes of similar components,

and also the means of joining and assembly

• defines suitable fits

• influences quality control procedures.

(Engineering Design A Systematic Approach; G. Pahl, W. Beitz; Page: 356)

Surface model:

Surface models are B-rep models that represent an object as a set of closed connected higher order surface patches. In majority of CAD/CAM applications, such surface models are required. They offer better continuity across patch boundaries compared to meshed or faceted models. Further, contour models become inapplicable when the point cloud is not arranged in the sliced form. The degree of patches and the continuity across boundaries vary depending on the nature of the object and hence its point cloud. Point cloud of prismatic objects can generally be modeled using quadric surfaces, e.g., planes with C0 (position) continuity, or in some cases conics with C1 (slope) continuity. When designing the exterior of automobiles, household appliances, cellular phones and aerospace components, free form patches (e.g., Bezier or B-spline) are usually employed to enhance the design features and functionality.

(Computer Aided Engineering; Anupam Saxena, Birendra Sahay; Page: 301 )

IGES:

IGES enables the exchange of model databases among CAD/CAM systems. IGES contains more geometric entities such as, curves, surfaces, solid primitives, and Boolean (for Constructive Solid Geometry) operations. Wire-frame, surface modeling and solid modeling software can all be developed around IGES. It can transmit the property data associated with the drawings which helps in preparing, say, the bill of materials. Though these standards appear veiled or at the back end, they play a crucial role in creation of the application software.

(Computer Aided Engineering; Anupam Saxena, Birendra Sahay; Page: 7 )