| Computer-aided design (CAD) is the use of a wide | | | | Doug Ross at MIT in 1959.[6] |
| range of computer-based tools that assist engineers, | | | | It is argued that a turning point was the development |
| architects and other design professionals in their design | | | | of SKETCHPAD system in MIT in 1963 by Ivan |
| activities. It is the main geometry authoring tool within | | | | Sutherland (who later created a graphics technology |
| the Product Lifecycle Management process and | | | | company with Dr. David Evans). The distinctive feature |
| involves both software and sometimes | | | | of SKETCHPAD was that it allowed the designer to |
| special-purpose hardware. Current packages range | | | | interact with his computer graphically: the design can |
| from 2D vector based drafting systems to 3D solid | | | | be fed into the computer by drawing on a CRT |
| and surface modellers. | | | | monitor with a light pen. Effectively, it was a prototype |
| CAD is sometimes translated as "computer-assisted", | | | | of graphical user interface, an indispensable feature of |
| "computer-aided drafting", or a similar phrase. Related | | | | modern CAD. |
| acronyms are CADD, which stands for | | | | First commercial applications of CAD were in large |
| "computer-aided design and drafting", CAID for | | | | companies in the automotive and aerospace industries, |
| Computer-aided Industrial Design and CAAD, for | | | | as well as in electronics. Only large corporations could |
| "computer-aided architectural design". All these terms | | | | afford the computers capable of performing the |
| are essentially synonymous, but there are some subtle | | | | calculations. Notable company projects were at GM |
| differences in meaning and application. | | | | (Dr. Patrick J.Hanratty) with DAC-1 (Design Augmented |
| CAD was originally the three letter acronym for | | | | by Computer) 1964; Lockhead projects; Bell GRAPHIC |
| "Computer Aided Draughting" as in the early days | | | | 1 and at Renault (Bezier) – UNISURF 1971 car |
| CAD was really a replacement for the tradition | | | | body design and tooling. |
| draughting board. But now is the term is often | | | | One of the most influential events in the development |
| interchanged with "Computer Aided Design" to reflect | | | | of CAD was the founding of MCS (Manufacturing and |
| the fact that modern CAD tools do much more than | | | | Consulting Services Inc.) in 1971 by Dr. P. J. Hanratty[7], |
| just draughting. | | | | who wrote the system ADAM (Automated Drafting |
| Introduction | | | | And Machining) but more importantly supplied code to |
| CAD is used to design, develop and optimize products, | | | | companies such as McDonnell Douglas (Unigraphics), |
| which can be goods used by end consumers or | | | | Computervision (CADDS), Calma, Gerber, Autotrol and |
| intermediate goods used in other products. CAD is also | | | | Control Data. |
| extensively used in the design of tools and machinery | | | | As computers became more affordable, the |
| used in the manufacture of components, and in the | | | | application areas have gradually expanded. The |
| drafting and design of all types of buildings, from small | | | | development of CAD software for personal desk-top |
| residential types (houses) to the largest commercial | | | | computers was the impetus for almost universal |
| and industrial structures (hospitals and factories). | | | | application in all areas of construction. |
| CAD is mainly used for detailed engineering of 3D | | | | Other key points in the 1960s and 1970s would be the |
| models and/or 2D drawings of physical components, | | | | foundation of CAD systems United Computing, |
| but it is also used throughout the engineering process | | | | Intergraph, IBM, Intergraph IGDS in 1974 (which led to |
| from conceptual design and layout of products, through | | | | Bentley MicroStation in 1984) |
| strength and dynamic analysis of assemblies to | | | | CAD implementations have evolved dramatically since |
| definition of manufacturing methods of components. | | | | then. Initially, with 2D in the 1970s, it was typically limited |
| CAD has become an especially important technology | | | | to producing drawings similar to hand-drafted drawings. |
| with benefits, such as lower product development | | | | Advances in programming and computer hardware, |
| costs and a greatly shortened design cycle, because | | | | notably solid modeling in the 1980s, have allowed more |
| CAD enables designers to lay out and develop their | | | | versatile applications of computers in design activities. |
| work on screen, print it out and save it for future | | | | Key products for 1981 were the solid modelling |
| editing, saving a lot of time on their drawings. | | | | packages -Romulus (ShapeData) and Uni-Solid |
| Designers have long used computers for their | | | | (Unigraphics) based on PADL-2 and the release of the |
| calculations. Initial developments were carried out in the | | | | surface modeler CATIA (Dassault Systemes). |
| 1960s within the aircraft and automotive industries in | | | | Autodesk was founded 1982 by John Walker, which |
| the area of 3D surface construction and NC | | | | led to the 2D system AutoCAD. The next milestone |
| programming, most of it independent of one another | | | | was the release of Pro/ENGINEER in 1988, which |
| and often not publicly published until much later. Some | | | | heralded greater usage of feature-based modeling |
| of the mathematical description work on curves was | | | | methods and parametric linking of the parameters of |
| developed in the early 1940s by Isaac Jacob | | | | features. Also of importance to the development of |
| Schoenberg, Apalatequi (Douglas Aircraft) and Roy | | | | CAD was the development of the B-rep solid modeling |
| Liming (North American Aircraft), however probably | | | | kernels (engines for manipulating geometrically and |
| the most important work on polynomial curves and | | | | topologically consistent 3D objects) Parasolid |
| sculptured surface was done by Pierre Bezier | | | | (ShapeData) and ACIS (Spatial Technology Inc.) at the |
| (Renault), Paul de Casteljau (Citroen), Steven Anson | | | | end of the 1980s and beginning of the 1990s, both |
| Coons (MIT, Ford), James Ferguson (Boeing), Carl de | | | | inspired by the work of Ian Braid. This led to the |
| Boor (GM), Birkhoff (GM) and Garabedian (GM) in the | | | | release of mid-range packages such as SolidWorks in |
| 1960s and W. Gordon (GM) and R. Riesenfeld in the | | | | 1995, SolidEdge (Intergraph) in 1996, and IronCAD in |
| 1970s. | | | | 1998. Today CAD is one of the main tools used in |
| The term "computer-aided design" was coined by | | | | designing products. |