3D Curve Techniques and Tips Don LaCourse, eDocHelp
November 15, 2004
reprinted by permission from
The table below lists some of the more common methods of
constructing curve geometry in a 3D CAD system. Our emphasis here is to
provide tips for curve construction that can ultimately affect their usage
in a solid model. The following list of tips are keyed to their applicable
curve technique in the table.
3D CAD Tips
- Curve endpoints that are required to connect should always
remain coincident.
- Concatenated (joined) curves should not deviate from their
disjointed curve paths. Look for deviations close to their joined
endpoints.
- Local curve modifications should not unknowingly affect associated
curves and surfaces.
- Be aware that some curves are approximations such as those generated
from the intersection of two surfaces or the result of a curve projected
onto a surface.
- It is preferred that curves be generated from existing curves and
surface boundaries whenever possible.
- Reference curves not used in construction should be kept on a
separate layer.
- Techniques that maintain curvature and tangency with other curves
are recommended.
- Large offset distances of fluctuating curvatures can produce
unexpected results.
- Only curve deviations within specified geometry tolerances are
acceptable.
Click on image to enlarge About the Author Don LaCourse is principal partner of eDocHelp, which provides e-documentation, online help, technical writing and 3D modeling services for the CAD/CAM, manufacturing and other service-oriented industries. eDocHelp recently launched 3DCADTips, a 3D CAD resource site. Don has over 25 years of experience in design and documentation. He gained much of his experience during his 10 years as a tier-one automotive designer with Textron, Inc. He also helped NASA and the European Space Agency (ESA) design and document their joint SpaceLab 1 project that flew on board several of the early space shuttle missions. Don also brings product and injection mold design and documentation experience to eDocHelp. Don had his first book published in 1995 serving as editor-in-chief for the McGraw-Hill publication "Handbook of Solid Modeling," where he contributed, edited and managed over 25 industry-leading authors. He is currently a contributing editor for Cadalyst magazine.
More Select MCAD Articles
| 
