#1 Full form of CAD= Computer – Aided Design
What is CAD?
The computer-aided design better known by its acronym English CAD is when different graphics programs are used to create a series of images.That joint create a larger image ( so to speak) or better known as drawing.
The CAD is also used as a means of expression by means of a computer and a graphics manager. In turn, it can be said that it is also considered as a relatively new revolutionary drawing technique, with which drawings can be made.
It can also be found denoted by the acronym CADD ( computer-aided design and drafting ), which means sketch and computer-aided design.
These tools can be divided basically into 2D drawing programs and 3D modeling. 2D drawing tools are based on geometric vector entities such as points,lines, arcs and polygons, with which you can operate through a graphical interface. 3D modelers add surfaces and solids.
The CAD was mainly invented by a Frenchman, Pierre Brazier, engineer of the Arts et Metiers Paris Tech. The engineer developed the fundamental principles of CAD with his UNI SURF program in 1966.
The user can associate to each entity a series of properties such as color, layer, line style, name, geometric definition, material, etc., which allow handling the information in a logical way.
So in short and simple, the CAD is the use of a wide range of computational tools that assist engineers, architects.And other design professionals in their respective activities in any computer system to assist the designer in his specific task.
The History of CAD Software: How It All Started
The term CAD was created by American computer scientist Douglas Taylor Ross, who at the time saw how important it could become to use these tools.The CAD software is utilized to promote productivity, improve project quality, improve communications through documentation, and originate a database for manufacturing.
The beginning of CAD / CAM occurred in 1957 when the father of CAD / CAM, Dr. Patrick Han ratty developed PRONTO, the first commercial numerical control (CNC) system.
The accuracy, versatility, and editing capabilities of CAD / CAM designs have revolutionized the engineering, architecture, and manufacturing landscape. And some industry analysts estimate that 70 percent of all mechanical 3D CAD / CAM systems currently available have their roots back in code original Hanratty.
With its introduction in 1957, it was still decades before small, affordable computers could run the software. It means pencils and paper would continue to be the designer’s main way of creating designs for over 30 years.
But the groundwork was predicted for the future in which CAD software would become a key tool in architecture, interior design, mechanical engineering and in various other branches of the industry.
In 1960, Ivan Sutherland as part of his Ph.D. completion dissertation at the Massachusetts Institute of Technology (MIT), created SKETCHPAD. The world’s first CAD software, an innovative system that was a graphical editor that demonstrated the basics and viability of computer technical design.
Although primitive compared to today’s CAD software. Sketchpad was an innovative CAD software as the designer interacted with the computer graphically, utilizing a light pen to draw on the computer monitor.
Due to the high cost of the first computers, the use of CAD software was restricted to companies in the aerospace industry and large automakers. Such as General Motors, which became the first commercial users of the CAD Software. Dr. Hanraty co-designed one of these CAD systems in General Motors Research Laboratories in the mid-1960s.
These were not yet freely marketed in the market and their development was particularly focused on the demand of those sectors. First-generation CAD software systems were 2D drawing applications created by a manufacturer’s internal IT group. And primarily designed to automate repetitive design tasks.
In the same decade, the MIT Mathematics Laboratory, now called the Department of Computer Science, was responsible for leading research and development of 2D CAD software.
Elsewhere in the world, as in Europe, this type of activity was being started and other prominent developers were emerging. By the 1970s, CAD software was no longer just a research target and was now freely marketed.
At the same time, 3D CAD software was developed, the first of which was Computer Aided Three Dimensional Interactive Application (CATIA).It was created in 1977 by the French company Av ions Marcel Dassault, then CA DAM client, to develop the Mirage Dassault.
To be more specific, the history of the development of CAD can be presented chronologically like shown below:
- 1950 – Start of computer applications to aid engineering. Creating monochrome graphics from a computer.
- 51 – Appearance of the first graphics terminals and printers
- 53 – Appearance of first printers
- 58 – Data acquisition devices
- 62 – First three-dimensional graphics work
- 70 – IBM revolutionizes the CAD market with the standardization of graphical language and computational techniques for 3D
- 80 – Systems are beginning to be developed that interconnect the software directly to the production
- 90 – Development of robust operating systems for the application in computers, reduction of costs in hardware and “super” specialized users
These systems provide a number of tools for constructing flat geometric entities (such as lines, curves, polygons) or even three-dimensional objects (cubes, spheres, etc.). They also provide tools for relating these entities or objects. For example: creating a rounding (fillet) between two lines or subtracting the shapes of two three-dimensional objects to get a third.
A basic division between CAD software is based on the program’s ability to draw only in 2 dimensions or to create three-dimensional models as well.The latter being further subdivided in relation to which technology they use as a 3D modeler.
There are basically two types of 3D modeling: by polygons and by NURBS. In software, you can exchange between the 3D model and the 2D drawing. For example, the 2D drawing can be generated automatically from the 3D model.
There are specific CAD models that simulate the manufacturing conditions, ie the tools used in the drawing are the same as those available on the factory floor (these are usually called CAM programs ). Also in the architecture, there are specific CADs that automatically draw walls, roofs, and other constructions. The software most advanced CAD use the so-called parametric modeling. It allows design changes by simply input numbers indicating dimensions and relationships between entities or drawn objects.
- CAD Analytical: It uses analytical procedures to define its limits or actions. The analytical CAD type programs emerged after the first graphical methods due to the need to quantify. And allow the evaluation of the results of the variables involved in the structural design. In analytical CADs the drawing remains in the memory of the computer as a series of point-coordinate relationships, sense. Andthe direction in vector programs or as a group of pixels, in programs of rendering and treatment of images.
- CAD Parametric: It uses parameters to define its limits or actions. A parametric CAD program differs basically from any other traditional, in a key aspect. In a parametric program, the visual information is part of the information available in the data bank.That is, a representation of the information as an object, in the memory of the computer. At present, parametric CAD has replaced, almost completely, classic three-dimensional design techniques through the modeling of solids and surfaces. And has become essential knowledge for any professional of engineering or technical computing.
CAD System categories
CAD systems can be classified according to different criteria. Looking at the extension of the domain, intended as a field of use, we can distinguish between:
- Horizontal CAD systems: These are CAD systems with a very wide domain, which can be used successfully in different application contexts. Such as architectural and mechanical design. The commands offered by these systems are independent of a specific application context. You will, therefore, have commands as a line trace without any notion if the line represents a wall of a building or the edge of metal support.
- Vertical CAD systems: These are restricted domain systems, oriented to a particular application context, with specific commands and features for that context. For example, a vertical CAD system for interior design will offer commands to create and position different types of walls and place doors and windows on them. Industrial-oriented CADs and especially mechanical constructions in the broad sense are referred to as Mcads.
An alternative classification, widely used in the commercial sphere, divides the CAD systems into three main bands based on price and functionality:
- Low-end systems: They are CAD systems typically limited to 2D design, sold at a reasonable price (approximately less than € 300) and aimed at casual or non-professional users.
- Medium-low range systems: They are CAD systems typically limited to 2D design.They integrate various modules and allow you to manage design properties, sold at an affordable price and aimed at professional artisans, small companies, installers and all those who do not make the design own core business.
- Mid-range systems: They are CAD systems that integrate 2D design with 3D modeling, sold at an average price. These systems are usually aimed at small or medium-sized companies and professionals. And are often integrated with vertical modules, that is, particularly suitable for speeding up daily tasks. Often they are also integrated with a suite of tools such as PDM for managing data regarding designed products.
- High-end systems: They are complex CAD systems that integrate 3D modeling with 2D design. And offer advanced data management supporting business processes that extend well beyond the technical office. They have high costs and are typically used by medium and large companies, as for mid-range systems, even with PDM.
Elements of CAD systems
The CAD process consists of four stages.
- Geometric modeling: A physical object is described as a mathematical or analytical form. The designer constructs his geometric model by issuing commands that create or perfect lines, surfaces, bodies, dimensions, and text. That gives origin to an exact and complete representation in two or three dimensions.
- Analysis and optimization of the design: After having determined the geometric properties, it undergoes an engineering analysis where the physical properties of the model can be analyzed (stresses, deformations, deflections, vibrations).
- Review and evaluation of the design: In this important stage it is checked if there is any interference between the various components. In order to avoid problems in the assembly and the use of the piece.
- Documentation and drawing (drafting): Finally, in this stage, detail and work plans are made. This can be produced in different views of the piece, handling scales in the drawings and making transformations to present different perspectives of the piece.
Improves the manufacture, development, and design of products with the help of the computer. With this process, it is intended to manufacture them with greater precision, at a lower price and much faster than if it were only made by man.
It also shows the complete process of manufacturing a specific product with each and every one of its characteristics such as size, contour, etc. All this is recorded on the computer in two-dimensional or three-dimensional drawings. These drawings or designs are stored on the computer.
So if the creator can subsequently improve them, or share them with others to refine their design. The manufacture of products through computer-aided design has many advantages over manufacturing with human operators. Among these are the reduction of labor cost, or the elimination of human errors.
Also, the computer simulates the operation of a certain product and checks it. With the computer-aided design, complex products can be manufactured that would be practically impossible for human beings to perform. It is estimated that in the future the manufacture of expensive simulators will be completely eliminated since everything will be checked by computer-aided design.
In the industry, it is where the greatest impact has been, since the design by means of the computer, increases production. And the precision with which the products are manufactured, than if only the man made them.
In the field of construction completely revolutionized the design of buildings, since it can be more precise and faster in its development. Because it is easy and safe, design through the aforementioned programs.
Advantages of its use
- It is possible to use libraries of common elements.
- The distinction between the original plane and the copy is eliminated.
- The storage of the plans is smaller, more reliable (taking certain security measures) and allows fast and accurate searches through databases.
- Increase the uniformity in the planes.
- The quality of the plans is greater. There are no studs, nor lines thicker than others.
- The time invested in the modifications is greatly reduced.
- Reduction of the time used in repetitive operations.
- The data can be exported to other programs to obtain calculations, make reports, presentations …
- You can get a 3D model to visualize it from any point of view.
- The data can be exported to CAE programs and CNC machines.
- Obtain simulations, animations and do kinematic analysis.
- They facilitate teamwork.
- Integration of business software with CAD
Most CAD programs require communication with the ERP system since the drawings in the program are the basis of other central processes within the company. The companies that have a great integration of CAD software in the ERP package are those that combine design and production. An example of one of these companies is Airbus.
Drawings in CAD also go through adaptations, revisions of different users or adjustments according to the customer’s comments. Therefore, the central control of versions of CAD drawings is very important. Keep in mind that not all document management systems can manage CAD drawings well.
An additional difficulty when looking for a document management system is that the company uses different CAD programs. Therefore, it is very important to find out which management systems comply with full CAD integration.
- Architecture, urban planning, civil engineering: construction design.
- Furniture: interior design.
- Electrical and mechanical engineering: design of electrical or mechanical equipment.
- Industrial design: design of consumer objects, such as furniture or household tools, recently also clothing.
- Plant engineering: wiring and air conditioning piping design.
- Electronics: design of electronic circuits, at the level of the wiring diagram, integrated circuit, printed circuit board, or entire system.
The Age of 2D CAD Design and 3D Modeling
Early CAD systems served as mere replacements for drawing boards and the design engineer began working on 2D. To create technical drawings consisting of primitive 2D wire frame structures.
Design productivity has increased, but many argue that only general design engineers needed to learn how to use computers and CAD. However, the modifications and revisions were easier than expected. And over time, CAD software and hardware became cheaper and affordable for midsize companies, so CAD software grew in functionality and ease of use.
3D wire frame features were developed in the early 1960s, and in 1969 MAGI launched Synths Vision, the first commercially available solid modeling program. Solid modeling has further enhanced the 3D capabilities of CAD systems.
The Revolution of CAD Software
Auto Cad was a major milestone in the evolution of CAD, setting the pace for the development of other CAD competitors, but was still predominantly 2D based.
All this changed in 1987 with the launch of PTC Pro / Engineer, a CAD program based on solid geometry and parametric techniques with features to define parts and assemblies. It ran on UNIX workstations, as the PCs still did not have the features required by the CAD programs.
Engineers were able to define parameters, features, and relationships, and the only thing that delayed the pace of parametric modeling at this time was the difficulty in investing time. And money in training and converting legacy data from other CAD programs to Pro / ENGINEER proprietary data format.
In the 1990s, the PC was able to do the calculations required by 3D CAD. In 1995, Solid Works was released, the first significant solid modeler for Windows and this was followed by Solid Edge, Inventor, and others.
That decade also saw many of the original 1960 CAD developers acquired by newer companies.And an industry consolidation in four leading companies – Auto desk, Assault System, PTC and UGS – along with a number of smaller developers.
Today’s CAD software
CAD / CAE / CAM systems are now widely accepted and used across the industry. These systems were transferred from costly workstations based mostly on UNIX PCs to off-the-shelf PCs. 3D modeling has become a and can be found even in applications for the general public, such as modeling 3D buildings in Google Maps.
The modern CAD era was marked by improvements in modeling, incorporation of analysis and management of the products we create, from design and engineering to manufacturing, sales, and maintenance, what we call Product Life cycle Management (PLM).
The 21st century also brought another evolution on the computing platform. With the introduction of large-scale PCs, smartphones, and tablets, CAD has become available in cloud, web and mobile technologies.
Now it’s possible for engineers to work with CAD on any Mac, Windows or tablet. Of course, the availability of CAD also brought an increase in the use of this software by the consuming public.
Nowadays, CAD systems are compatible with all major platforms – Windows, Linux, UNIX, and Mac OS X, and some systems even support multiple platforms.
In addition, the interaction between man and machine was changed. Typically, designers use a computer mouse to work with CAD programs. However, designers can also use a stylus and scan a tablet. In addition, there has been much development in the interaction of the CAD-human interface – from touch screens to Virtual Reality (VR) / Augmented Reality (RA).
Auto CAD is the software of the type CAD – computer-aided design or computer aided design – created and marketed by Auto desk, Inc. since 1982. It is used mainly for the elaboration of pieces of technical drawing in two dimensions (2D) and for creation of models three-dimensional (3D).
In addition to the technical drawings, the software has made available in its latest versions several features for viewing in various formats. It is widely used in architecture, interior design, mechanical engineering and in various other branches of industry.
In fact, Auto Cad is the name of a product, just like Windows, Office (Word, Excel, …), etc. There are other CAD software like Micro Station, Vector Works, Intelligent Cad; for three-dimensional and parametric modeling like Catia, Pro Engineer, Solid Works, Solid Edges, etc.