| Summary: | 碩士 === 元智大學 === 機械工程研究所 === 83 === With the integration of CAD/CAM systems and computer controlled
coordinate measuring mechine（CMM） , reverse engneering has
emerged as an important design tool in recent years. The
techniques mainly involve measuring and digitization from
physical parts and surface model reconstruction. In this
thesis, the physical parts was scanned by CNC type coordinate
measuring mechine equipped with a touch- trigger probe. A
correcting procedure for the probe center offset is developed
in this thesis. Then, using the surface model was
reconstructed from measured points data by the cubic-spline
methode. Features of this thesis are: (1)we use the quadtree-
like method to achieve the multi-level measuring strategy.
(2)The zero-crossing method is applied to detect the
characteristic curve of compound suface, then we can found the
boundary (edge)variety sharply. (3) The block is a unit use to
estimate the accuracy of the reconstructed surface achieved by
compare the predict points and check points.If the
reconstructed-error larger than the specific limit,this block
will be redivided and remeasured again, until all blocks reach
the precision requirement. In the end, the entire measurment
strategy, the edge detect result, and the reconstructed cubic-
spline surfaces and its error analysis will be proved by two
examples, one is a multi-slope magnatic set, another is a semi-
sphere set.
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