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GEOMETRY OF PLANAR CAM PROFILES 203

7.5 COMMERCIAL SOFTWARE PACKAGES

The synthesis and design of cam mechanisms can be eased by using the capabilities
offered by CAD packages. Extensive CAD software is commercially available, with
new packages and new features appearing every year. Among these features, we can
mention the plotting of functions, the rotation and translation of planar rigid figures,
and the determination of intersections of lines, curves, and surfaces. This function is impor-
tant, because to start with the design process we assume that the displacement program of
the follower is given as a smooth, explicit function of the input variable so that its deriv-
ative is available.
If only a discrete set of points is specified for the functions needed in the synthesis pro-
cedures, an interpolation is needed, which can be implemented by using software pack-
ages as well.
A representative list of commercial packages is given below.

• AUTOCAD: Comprehensive package for mechanical design and geometric analysis.
Runs mostly on Windows. Old versions run also on Unix. Vendor: Autodesk, Inc. Its
Web site is: http://info.autodesk.com/.
• VERSACAD: Basically a production-level CAD software. However, the 3DJoy module
is a modeler that offers high-powered spline-based modeling. Also, the Rhino module
can create, edit, analyze, and translate NURBS, surfaces, and solids. Runs on Windows.
Vendor: Archway Systems, Inc. Web site: http://www.versacad.com/
Other pertinent CAD software packages have more advanced features in terms of solid
modeling, assembly, and motion animation, e.g.,
• PRO/ENGINEER: Comprehensive package for mechanical design and analysis at large.
Its PRO/MECHANICA module provides motion analysis, simulation, and animation of
fairly complex mechanisms. Runs on Windows and Unix. Vendor: Parametric Technol-
ogy, Inc. Web site is: http://www.ptc.com/
• CATIA: This software package has advanced features that can be used for creating and
modifying free-form surfaces, complex solids, parametric modifications, and the use
of solids in a multimodel environment. Vendor: TBM Technologies. Web site is
http://www.catia.com/
• UNIGRAPHICS: High-end, comprehensive package with modules for finite-element
analysis, CAD/CAM, etc. It feature ADAMS, a general tool for mechanism and multi-
body-system analysis. No synthesis features are supported. Vendor: Unigraphics Solu-
tions. Web site: http://www.openitx.com/

Finally, general-purpose software for numerical and symbolic computations is included
below. This software becomes quite useful in the computation and plotting of the local
geometric properties, whereby some statistics are occasionally needed, like mean value
and standard deviation of pressure-angle of curvature values. We thus have

• MATLAB: General-purpopse numerical analysis package with excellent routines for
equation-solving and optimization. To be used as a support for linkage synthesis.
Vendor: The Mathworks Inc. (www.mathworks.com/ieex).
• MACSYMA (www.macsyma.com), MAPLE (www.maplesoft.com), and MATHE-
MATICA (www.wolfram.com): commercial packages for symbolic computations. These
packages feature capabilities for numerical computations.