Its use In electronic design is known as Electronic Design Automation, or DEAD. In mechanical design, it is also known as computer-aided drafting (CAD) or computer-aided design and drafting (CAD),[3] which describes the process of creating a technical drawing with the use of computer software. [4] CAD software for mechanical design uses either vector based graphics to depict the objects of traditional drafting, or may also produce raster graphics showing the overall appearance of designed objects.
However, it involves more than Just shapes.As in the manual drafting of technical and engineering drawings, the output of CAD must envoy Information, such as materials, processes, dimensions, and tolerances, according to application-specific conventions. CAD may be used to design curves and figures in two-dimensional (ID) space; or curves, surfaces, and solids in three- dimensional (ID) space. [5] CAD is an important industrial art extensively used in many applications, Including automotive, shipbuilding, and aerospace Industries, Industrial and architectural design, prosthetics, and many more.CAD Is also widely used to produce computer animation for special effects in movies, advertising and technical manuals. The modern ubiquity and power of computers means that even perfume bottles and shampoo dispensers are designed using techniques unheard of by engineers of the sass.
Because of its enormous economic importance, CAD has been a major driving force for research in computational geometry, computer graphics (both hardware and software), and discrete differential geometry. 6] The design of geometric models for object shapes, In particular, Is occasionally called computer-laded geometric design (CAGE). [7] While the goal of automated CAD systems is to increase efficiency, they are not necessarily the best way to allow comers to understand the geometrical principles of Solid Modeling. For this, scripting languages such as Plasma (Programming Language of Solid Modeling) are more suitable.
Overview Beginning In the sass computer-aided design programs reduced the need of draftsmen significantly, especially in small to mid-sized companies.Their affordability drafting work, eliminating the need for entire departments. In today's world, many students in universities do not learn manual drafting techniques because they are not required to do so. The days of hand drawing for final drawings are virtually over. Universities no longer require the use of protractors and compasses to create drawings, instead there are several classes that focus on the use of CAD software.
Current computer-aided design software packages range from ID vector-based drafting systems to ID solid and surface meddlers.Modern CAD packages can also frequently 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 modeling, in which case it may be marketed as CAD. CAD is used in the design of tools and machinery and in the drafting and sign of all types of buildings, from small residential types (houses) to the largest commercial and industrial structures (hospitals and factories).
8] CAD is mainly used for detailed engineering of ID models and/or ID 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. Furthermore many CAD applications now offer advanced rendering and animation abilities so engineers can better visualize their product designs.CAD has become an especially important technology within the scope of computer-aided technologies, with benefits such as lower product development costs and a greatly shortened design cycle.
CAD enables designers to layout and develop work on screen, print it out and save it for future editing, saving time on their drawings. Uses 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 one part of the whole Digital Product Development (DIP) activity within the Product Lifestyle Management (PALM) processes, and as such is used together with other tools, which are either integrated modules or stand-alone products, such as: Computer-aided engineering (CAE) and Finite element analysis (FEE) Computer-aided manufacturing (CAM) including instructions to Computer Numerical Control (CNN) machines Photo realistic rendering Document management and revision control using Product Data Management (PDP).CAD is also used for the accurate creation of photo simulations that are often squired in the preparation of Environmental Impact Reports, in which computer- environments to represent what that locale will be like were the proposed facilities allowed to be built.
Potential blockage of view corridors and shadow studies are also frequently analyzed through the use of CAD. CAD has been proven to be useful to engineers as well. Using four properties which are history, features, parameterization, and high level constraints.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. Parameters and constraints can be used to determine the size, shape, and the different modeling 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.
Types See also: List of computer-aided design editors There are several different types of each requiring the operator to think differently about how to use them and design their virtual components in a different manner for each. There are many producers of the lower-end ID systems, including a umber of free and open source programs. These provide an approach to the drawing process without all the fuss over scale and placement on the drawing sheet that accompanied hand drafting, since these can be adjusted as required during the creation of the final draft. ID warfare is basically an extension of ID drafting (not often used today).Each line has to be manually inserted into the drawing.
The final product has no mass properties associated with it and cannot have features directly added to it, such as holes. The operator approaches these in a similar fashion to the D systems, although many ID systems allow using the warfare model to make the final engineering drawing views. ID "dumb" solids are created in a way analogous to manipulations of real world objects (not often used today). Basic three-dimensional geometric forms (prisms, cylinders, spheres, and so on) have solid volumes added or subtracted from them, as if assembling or cutting real-world objects.
Two- dimensional projected views can easily be generated from the models. Basic ID solids don't usually include tools to easily allow motion of components, set limits to their motion, or identify interference between components. D parametric solid modeling requires the operator to use what is referred to as "design intent". The objects and features created are adjustable. Any future modifications will be simple, difficult, or nearly impossible, depending on how the original part was created. One must think of this as being a "perfect world" representation of the component.
If a feature was intended to be located from the center of the part, the operator needs to an arbitrary point, as he could when using "dumb" solids. Parametric solids require the operator to consider the consequences of his actions carefully. Some software packages provide the ability to edit parametric and non-parametric geometry without the need to understand or undo the design intent history of the geometry by use of direct modeling functionality. This ability may also include the additional ability to infer the correct relationships between selected geometry (e. .
, tangency, egocentricity) which makes the editing process less time and labor intensive while still freeing the engineer from the burden of understanding the models. These kind of non-history based systems are called Explicit Models or Direct CAD Meddlers. Top end systems offer the capabilities to incorporate more organic, aesthetics and ergonomic features into designs. Freedom surface modeling is often combined with solids to allow the designer to create products that fit the human form and visual requirements as well as they interface with the machine.Technology A CAD model of a computer mouse.
Originally software for Computer-Aided Design systems was developed with computer languages such as Fortran, but with the advancement of object-oriented programming methods this has radically changed. Typical modern parametric eater based modeled and freedom surface systems are built around a number of key C modules with their own Apish. A CAD system can be seen as built up from the interaction of a graphical user interface (GU') with NURSES geometry and/or boundary representation (B-rep) data via a geometric modeling kernel.A geometry constraint engine may also be employed to manage the associative relationships between geometry, such as warfare geometry in a sketch or components in an assembly. Unexpected capabilities of these associative relationships have led to a new form of prototyping called digital prototyping. In contrast to physical prototypes, which entail manufacturing time in the design.
That said, CAD models can be generated by a computer after the physical prototype has been scanned using an industrial CT scanning machine.Depending on the nature of the business, digital or physical prototypes can be initially chosen according to specific needs. Today, CAD systems exist for all the major platforms (Windows, Linux, UNIX and Mac SO X); some packages even support multiple platforms. Right now, no special hardware is required for most CAD software. However, some CAD systems can do graphically and computationally intensive tasks, so a modern graphics card, high speed (and possibly multiple) Cups and large amounts of RAM may be recommended.
The human-machine interface is generally via a computer 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 Spacemen/Spacewalk. Some systems also support stereoscopic glasses for viewing the ID model. History Designers[10][11][12][13] have long used computers for their calculations. Initial developments were carried out in the sass within the aircraft and automotive independent of one another and often not publicly published until much later.
Some of the mathematical description work on curves was developed in the early sass by Robert Isaac Newton from Pawtucket, Rhode Island. Robert A.
