CAD or Computer Aided Design also known as Computer Aided Design and Drafting (CADD). Primarily this is the use of computer technology to assist in the design, modification and optimization of technical drawings. These drawings can be used as blue prints for designers, civil engineers, architects, in fact anywhere that a product or landscape modification is required.
There are many CAD packages on the market, each one being a variation on a theme. The purpose of this type of software package is to increase the productivity of the designers using it. Designers and draftsmen used to produce drawing or plans on a drawing board. Although this was a skill in itself any mistakes were difficult to rectify. With the development of CAD mistakes can be easily put right prior to the final drawing being printed on a HP Designjet.
With the increase in computing technology and the refinement of CAD programs technical drawing can be stored easily with minimum of fuss. The completed drawings can be sent electronically across the world in a matter of seconds, the designer no longer needs to be on site. This also means a large data base of drawings and plans can be easily accessible for the designers or the engineers as requited.
Types of CAD
CAD software can be used in two different ways – Vector based graphics are used to depict the objects of traditional drafting or raster graphics can be used to show the overall appearance of designed objects
CAD often involves more than shapes, for producing objects. Many designers use computer aided design in town planning to show new road layouts. Architects use CAD to design new or modify existing buildings. The purpose of the CAD design is to convey information such as materials, dimensions, processes and tolerances according to per-determined specifications.
CAD can be used to design curves and figures in two-dimensional (2D) space; or curves, surfaces, and solids in three-dimensional (3D) space. These can then be printed on a traditional HP plotter, such as a DesignJet T790 or the HP DesignJet Color 3D printer.
Uses of CAD
The use of Computer Aided Design is extensive. It has become an important part of the design process and is extensively used in many applications, including automotive, shipbuilding, and aerospace industries, industrial and architectural design, and many more. CAD is also widely used in the film industry to produce computer animation for special effects in movies, advertising and technical manuals.
With the world going “green” the power of computer aided design means that everyday objects such as perfume bottles, shampoo dispensers and tin cans for food storage are designed using techniques unheard of by engineers of the 1960s. Because of its enormous economic importance, CAD has been a major driving force for research in computer graphics (both hardware and software), and discrete differential geometry.
Despite is obvious versatility and uses and its undoubted ability to increase productivity, Computer Aided Design is not necessarily the best way for newcomers to understand the geometrical principles of Solid Modelling. This requires a specialist design language based on the same principles. One such solution to this is PLaSM – Programming Language of solid Modelling.
In the early 1980,s the upsurge and versatility of computers and computer aided design programs significantly reduced the need for qualified draftsmen especially in small to medium sized companies. Design programs that could be run form a small personal computer enabled engineers to carry out their own drafting and design work. This eventually eliminated the need for entire design departments.
Nowadays many universities do not offer manual drafting course, because they are not required to do so. The days of hand drawing to produce the final design concept are all but over. Students no longer require to learn the use of protractors and compasses to create drawings; instead they plump for classes that focus on the use of CAD software.
There are several types of computer-aided design software packages. These range from 2D vector-based drafting systems to 3D solid and surface modellers. Powerful computer systems and modern CAD packages can allow rotations in three dimensions, allowing viewing of a designed object from any desired angle, even from the inside looking out. Some CAD software is capable of dynamic mathematical modelling, in which case it may be marketed as CADD.
The uses of CAD in industry are limitless. It is used extensively in the design of tools and machinery and in the drafting and design of all types of buildings, from small residential types (houses) to the largest commercial and industrial structures (hospitals, factories even the massive skyscrapers that are appearing throughout the world).
The use of CAD is mainly for detailed engineering of 3D models and/or 2D drawings of physical components, but it is also used throughout the engineering process from conceptual design and layout of products, through strength and dynamic analysis of assemblies to definition of manufacturing methods of components. It can also be used to design objects.
The importance of CAD within the design industry cannot be overlooked. With benefits such as lower product development costs and a greatly shortened design cycle. Computer Aided Design enables designers to layout and develop work on screen, print it out and save it for future editing, saving time and money on their drawings.
Computer-aided design is one of the many tools used by engineers and designers and is used in many ways depending on the profession of the user and the type of software in question.
CAD is also used for the accurate creation of photo simulations that are often required in the preparation of Environmental Impact Reports, in which computer-aided designs of intended buildings are superimposed into photographs of existing environments to represent what that locale will be like were the proposed facilities are constructed. Potential blockage of view corridors and shadow studies are also frequently analyzed through the use of Computer Aided Design
CAD has also been proven to be useful to engineers as well. Using four properties which are history, features, parametrization, and high level constraints (Zhang). The construction history can be used to look back into the model’s personal features and work on the single area rather than the whole model (Zhang). Parameters and constraints can be used to determine the size, shape, and the different modelling elements. The features in the CAD system can be used for the variety of tools for measurement such as tensile strength yield strength, also its stress and strain and how the element gets affected in certain temperatures.
Originally software for Computer-Aided Design systems was developed with computer languages such as Fortran. These were expensive as were the hardware platforms they required to run.
Right now, no special hardware is required for most CAD software. However, some Computer Aided Design systems can do graphically and computationally intensive tasks, so a modern graphics card, high speed (and possibly multiple) processors and large amounts of memory may be recommended.
The human-machine interface is generally via a mouse but can also be via a pen and digitizing graphics tablet. Manipulation of the view of the model on the screen is also sometimes done with the use of a space-mouse/space ball. Some systems also support stereoscopic glasses for viewing the 3D model.
Today Computer Aided Design systems are designed to run on all the major operating platforms, such as Windows, Linux, Unix and Mac OS X. Some CAD packages even have the capability to run on multiple platforms.Share on Facebook