- Impact printer (dot matrix)
- Non-impact printer include electrostatic, ink-jet and laser
- Flatbed plotters
- Drum plotters
CAD
systems may be considered as comprising a large number of functions
for creating or manipulating the design model. Traditionally,
there are two ways in which this is achieved:
Command-based systems
Command-based
systems operate by reading a command and its parameters
entered by the user, carrying out the required actions,
then waiting for the next command.
User Interface – Menu Driven
The
menu-driven approach contrasts markedly with the command
approach.
The basic principle is that the user is at any time
presented
with a list or menu of the functions that are available
to
be selected.
Rules
- The
most important of these rules are:
- A
clear, well presented screen layout.
- Easy
function selection by a well-structured menu system.
- Meaningful
function names.
- Meaningful
and helpful prompts to the user.
- Easily
accessible and clearly written help information.
The
main benefits of a computerized drafting and design system over
those of manual methods is this ability to represent the design
of a component or assembly in a geometrically accurate format
so that the same model can be used for other modelling, analysis
and manufacturing work.
The
functions can be said to fall into three categories:
- Synthesis type
functions are concerned mainly with the creation of geometric
features and drawing details.
- Modification functions include those which allow for the deletion and
editing of existing geometry or detail.
- Management functions
are concerned with how the drawing is presented
both on the screen and eventually on paper.
There
is a large variety of different CADD packages available on the market
these days and the design manager is faced with the enormous
problem of selecting a package to suit the demands
of
the company and its product range. A lot of ease and efficiency
has been obtained with the use of CADD systems. Among
the more widely used CAD systems are AutoCAD,
CATIA, SolidWorks, I-DEAS, and ProEngineer. Most of these packages have
both a 2D and 3D component or have an integrated 2D and
3D modeling system. The newer versions of drawing software
operate under a menu system which can be accessed through
keyboard input or mouse manipulation.
According
to these factors, the system must have;
- Functional abilities: the abilities to perform memory circuits.
- Memory capacity : evaluation between main and branch memory circuits.
- Data transfer characteristics : when we consider data transfer between
two computers, or a main computer and a station, we have
to keep in mind the need to decrease computing time
The
size of the company and the amount of investment capital available
will be one of the main deciding factors but there are many
other questions to be considered:
Mainframe
or PC/workstation platform?
Two
dimensions or three? Lines, surfaces or solids?
Other
analysis tools needed? Will the ability to transfer the
geometry
to these modelling and analysis systems be needed?
Compatibility
with other systems needed?
How
good is the maintenance and support from the suppliers?
How
much, how good and how long is the training?
How
easy is it to expand the system?
AutoCAD
is PCbased
CAD
software products (late 1982).
System
Requirements for AutoCAD
Windows
NT or Windows 95/98/2000
Intel
486 or Pentium processor or compatible
32
MB of RAM
50
MB of hard disk space
64MB
of disk swap space
2.5
MB of free disk space during installation only
CD-ROM
drive
640
x 480 VGA video display (1024 x 768 recommended)
Windows-supported
display adapter
Mouse or other pointing
device
