Page 160 - Fundamental of Engineering Design

Manipulation of data

◦ Basically, after completion a CAD file is obtained

◦ Used to a fit geometry to the large number of point is obtained

from digitizing

◦ The surface can be mathematically defined as algebraic or

parametric surface

◦ Surface fitting technique can be two type which are interpolation

and approximation technique as in table below:

Table 4.2 : Description on interpolation and approximation technique

Interpolation technique Approximation technique

Surfaces to be fitted through all the Surfaces represents generalized or

data points best fit to the data points

Uses when the data points are Uses when large number of data

accurately measured without error points are to be fitted

◦ For generation of functional part, the geometric model that has been

obtained can be used as the basis for variety of operation

◦ Operation such as automated process planning, automated manufacturing,

automated dimensional inspection and automated tolerance analysis
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