AutoCAD add-ons:
extension of the
graphical data input
Benjamin Falkovsky, Yakov Davidov
Engineering graphics department, MIREA,
The standard AutoCAD tools do not always fit the solution of classical
descriptive geometry problems in 3D space, but the system’s flexibility allows
us to create the necessary tools ourselves.
Built-in programming languages and
tools for creating the sequences of commands or "scenarios" (scripts)
extend the AutoCAD’s boundaries and simplify the dialogue between user and
system when solving the computer geometry problems.
We have designed and introduced to
scholastic process the AutoCAD add-ons which improve the knowledge of a student
for solving the 3D geometry problems.
Two scripts were written containing
the sequence of commands describing the plane translation from general to the
special position on two projection drawing with
necessary locations of the axes.
These scripts can also be used for
solving the linear geometrical figure problems, all types of the surface and
solid modeling problems.
surface MODELING
(add-on)
AutoCAD system allows us to work with surfaces.
There are parallelepiped 
(Box), triangular prism 
(Wedge), pyramid 
, Cone 
, Sphere 
, upper 
(Dome) and lower 
(Dish) half of the sphere, Torus 
and other surface
primitives in the list of standard surfaces, which can be built in AutoCAD.
AutoCAD can also create Revolved Surfaces 
, Tabulated Surfaces 
, surfaces on two lines 
(Ruled Surfaces) and
surfaces on four closed curves 
(Edge Surfaces). All
the other surfaces can be created using the three-dimensional (3D) mesh 
.
AutoCAD has two built-in programming languages: the list processing
language AutoLISP and Microsoft Visual Basic. Using these languages, two MIREA
students Yakov Davidov and Vladislav Karpachev wrote a number of AutoCAD
add-ons under a general name of NLTeam Utilities.
This program product includes tools required for building all of the
second order surfaces and screw surfaces.
The second order
surfaces
Working with program is
very simple: specify the surface type and its parameters in "The second
order surfaces" dialogue window (Fig. 1, a).
Fig. 1
The same surfaces can be
built with instrumental panels (c) or commands in main menu (b).
Examples of the NLTeam
surfaces
1. Ellipsoid. 2.
One-strip hyperboloid.
3. Two-strip hyperboloid. 4.
Elliptical cone
5. Elliptical paraboloid 6. Hyperbolic paraboloid
7. Elliptical cylinder 8. Hyperbolic cylinder
9. Parabolic cylinder
10. Screw
surfaces can be presented as ensemble points (a), ensemble objects (b) or 3D
array (c).
