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CAD/ CAM

CAD – (Computer Aided Design) the process of designing an item or product

using a computer.

Computer-aided design (CAD) is an electronic system for designing new parts

or products or altering existing ones, replacing drafting traditionally done by

hand. The heart of CAD is a powerful desktop computer and graphics

software that allow a designer to manipulate geometric shapes. The designer

can create drawings and view them from any angle on a display monitor. The

computer can also simulate the reaction of a part to strength and stress tests.

Using the design data stored in the computer’s memory, manufacturing

engineers and other users can quickly obtain printouts of plans and

specifications for a part or product. CAD cuts the cost of product development

and sharply reduces the time to market for new products. In 1970’s it made

an entry in the Textile and Apparel industry.

CAD/CAM is a shortening of Computer-Aided Design (CAD) and Computer-

Aided Manufacturing (CAM). The term CAD/NC (Numerical Control) is

equivalent in some industries.

CAD/CAM software uses CAD drawing tools to describe geometries used by

the CAM portion of the program to define a tool path that will direct the

motion of a machine tool to machine the exact shape that was drawn.

More about CAD/CAM

Computer-aided design (CAD) involves creating computer models defined by

geometrical parameters. These models typically appear on a computer

monitor as a three-dimensional representation of a part or a system of parts,

which can be readily altered by changing relevant parameters. CAD systems

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enable designers to view objects under a wide variety of representations and

to test these objects by simulating real-world conditions.

Computer-aided manufacturing (CAM) uses geometrical design data to

control automated machinery. CAM systems are associated with computer

numerical control (CNC) or direct numerical control (DNC) systems. These

systems differ from older forms of numerical control (NC) in that geometrical

data is encoded mechanically. Since both CAD and CAM use computer-based

methods for encoding geometrical data, it is possible for the processes of

design and manufacture to be highly integrated. Computer-aided design and

manufacturing systems are commonly referred to as CAD/CAM.

Origins of CAD/CAM

CAD had its origins in three separate sources, which also serve to highlight

the basic operations that CAD systems provide. The first source of CAD

resulted from attempts to automate the drafting process. The General Motors

Research Laboratories pioneered these developments in the early 1960s. One

of the important timesaving advantages of computer modeling over

traditional drafting methods is that the former can be quickly corrected or

manipulated by changing a model's parameters. The second source of CAD

was in the testing of designs by simulation. The use of computer modeling to

test products was pioneered by high-tech industries like aerospace and

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semiconductors. The third source of CAD development resulted from efforts

to facilitate the flow from the design process to the manufacturing process

using numerical control (NC) technologies, which enjoyed widespread use in

many applications by the mid-1960s. It was this source that resulted in the

linkage between CAD and CAM. One of the most important trends in

CAD/CAM technologies is the ever-tighter integration between the design and

manufacturing stages of CAD/CAM-based production processes.

The development of CAD and CAM and particularly the linkage between the

two overcame traditional NC shortcomings in expense, ease of use, and speed

by enabling the design and manufacture of a part to be undertaken using the

same system of encoding geometrical data. This innovation greatly shortened

the period between design and manufacture and greatly expanded the scope

of production processes for which automated machinery could be

economically used. Just as important, CAD/CAM gave the designer much more

direct control over the production process, creating the possibility of

completely integrated design and manufacturing processes.

The rapid growth in the use of CAD/CAM technologies after the early 1970s

was made possible by the development of mass-produced silicon chips and

the microprocessor, resulting in more readily affordable computers. As the

price of computers continued to decline and their processing power

improved, the use of CAD/CAM broadened from large firms using large-scale

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mass production techniques to firms of all sizes. The scope of operations to

which CAD/CAM was applied broadened as well. In addition to parts-shaping

by traditional machine tool processes such as stamping, drilling, milling, and

grinding, CAD/CAM has come to be used by firms involved in producing

consumer electronics, electronic components, molded plastics, and a host of

other products. Computers are also used to control a number of

manufacturing processes (such as chemical processing) that are not strictly

defined as CAM because the control data are not based on geometrical

parameters.

Past, Present & Future of CAD/CAM

Well before the development of Computer-aided design, the manufacturing

world adopted tools controlled by numbers and letters to fill the need for

manufacturing complex shapes in an accurate and repeatable manner. During

the 1950's these Numerically Controlled machines used the existing

technology of paper tapes with regularly spaced holes punched in them (think

of the paper roll that makes an old-fashioned player piano work, but only one

inch wide) to feed numbers into controller machines that were wired to the

motors positioning the work on machine tools. The electro-mechanical nature

of the controllers allowed digital technologies to be easily incorporated as

they were developed.

By the late 1960's Numerically Controlled machining centers were

commercially available, incorporating a variety of machining processes and

automatic tool changing. Such tools were capable of doing work on multiple

surfaces of a work piece, moving the work piece to positions programmed in

advance and using a variety of tools - all automatically. What is more, the

same work could be done over and over again with extraordinary precision

and very little additional human input. NC tools immediately raised

automation of manufacturing to a new level once feedback loops were

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incorporated (the tool tells the computer where it is, while the computer tells

it where it should be).

What finally made NC technology enormously successful was the

development of the universal NC programming language called APT

(Automatically Programmed Tools). Announced at MIT in 1962, APT allowed

programmers to develop postprocessors specific to each type of NC tool so

that the output from the APT program could be shared among different

parties with different manufacturing capabilities.

In 1959, CAD (computer aided design) as a conception was proposed. But

since it was introduced into the clothing industry in 1970s, it has accelerated

to change the traditional manual way of production. At the same time, CAD

has been developing at a surprising speed. At present, the application of the

computer has involved in various clothing fields of design, manufacture, sales,

management, and education. It has included the whole process of clothing

production.

Advantages and Disadvantages

Modeling with CAD systems offers a number of advantages over traditional

drafting methods that use rulers, squares, and compasses. For example,

designs can be altered without erasing and redrawing. CAD systems also offer

"zoom" features analogous to a camera lens, whereby a designer can magnify

certain elements of a model to facilitate inspection. Computer models are

typically three dimensional and can be rotated on any axis, much as one could

rotate an actual three dimensional model in one's hand, enabling the designer

to gain a fuller sense of the object. CAD systems also lend themselves to

modeling cutaway drawings, in which the internal shape of a part is revealed,

and to illustrating the spatial relationships among a system of parts.

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Chris Mc-Mahon and Jimmie Browne summarize limitations of existing

CAD/CAM systems as follows: "There is a widespread view that CAD is not yet

adequate as an aid to the designer in generating a design. CAD is considered

to concentrate rather too much on providing means of representing the final

form of the design, whereas designers also need a continual stream of advice

and information to assist in decision-making…. The tasks of CAD systems of

the future are therefore to represent a wider variety of a design's properties,

in terms that are familiar to engineers and of a company's organization and

equipment that influence design."

Other limitations to CAD are being addressed by research and development in

the field of expert systems. This field derived from research done on artificial

intelligence. One example of an expert system involves incorporating

information about the nature of materials—their weight, tensile strength,

flexibility, and so on—into CAD software. By including this and other

information, the CAD system could then "know" what an expert engineer

knows when that engineer creates a design. The system could then mimic the

engineer's thought pattern and actually "create" a design. Expert systems

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might involve the implementation of more abstract principles, such as the

nature of gravity and friction, or the function and relation of commonly used

parts, such as levers or nuts and bolts. Expert systems might also come to

change the way data is stored and retrieved in CAD/CAM systems,

supplanting the hierarchical system with one that offers greater flexibility.

Recent technical developments have fundamentally impacted the utility of

CAD/CAM systems. For example, the ever-increasing processing power of

personal computers has given them viability as a vehicle for CAD/CAM

application. Another important trend is toward the establishment of a single

CAD-CAM standard, so that different data packages can be exchanged without

manufacturing and delivery delays, unnecessary design revisions, and other

problems that continue to bedevil some CAD-CAM initiatives. Finally, CAD-

CAM software continues to evolve on a continuing basis in such realms as

visual representation and integration of modeling and testing applications.

Advantages and Disadvantages of CAD

Advantages:

The software makes it very easy to change or adjust parts of the design

Different stages or versions of a design can be stored on the hard disk

and accessed at any time.

Copies of the design can be produced by using a plotter or A3 printer.

Images can be viewed from any angle

The design can be emailed to another office so that they can give

feedback

The software can automatically check that the design meets any rules

such as “the minimum width of any part must be more than 1mm”.

While creating the design, an error message will display if any part of

the design breaks this rule.

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If one part of the design e.g. an aircraft wing, needs to be joined to

another part of the design e.g. the body of an aircraft, then the software

can check that both designs will fit together properly.

Disadvantages:

CAD/CAM is that have to learn the software behind each.

Difficulty keeping track of changes when many people are working

on drawings for a project (Revision Control).

Protecting your ideas is difficult when you must share your

drawings with customers and contractors, but you need input about

design questions (Intellectual Property).

Sharing your drawings with other companies who may not be using

the same CAD programs.

Advantages and Disadvantages of CAM

Advantages:

Each component is made exactly the same.

Machines can work 24 hours a day and don’t require breaks.

Computers monitor the production and test samples using robots.

These tests can be exhaustive and frequently a product is tested to

destruction to estimate its useful life.

Computers and machines do not get bored doing repetitive tasks.

Disadvantages:

Potential for wasted parts and materials due to inaccurate CAD.

Machinery can break down, halting production.

Initial setup of the production line can be expensive, making limited

runs cost-prohibitive.

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Uses of CAD/CAM

CAD/CAM is currently in use in several industries such as architecture,

electronics, mechanical and production engineering and textiles. There are

several kinds of CAD packages available in the market today, with different

kinds of features. Most of the packages are ready-to-use with a number of

graphics, which the user can select according to his or her requirements. User

friendly and requirement-compatible environments being embedded are a

clear merit, enabling easy usage.

With the advent of large-scale computer usage, there increased the demand

for design packages such as CAD for the twin purpose of beating the

monotony of paper-based engineering design and to speed up design and

production timeframes. With miniaturization of computers and electronics

and powerful memory features, CAD/CAM has now attained great heights, as

far as industrial application goes.

Application in Fashion

At various stages of fashion design, CAD has come to play a pivotal role.

Starting from the initial design and prototyping stages, where the firm

narrows in to a retail able and feasible design, the array of choices displayed

visually facilitate the job significantly. Proceeding to the manufacturing stage,

mass production that has always posed a challenge to industries has been

simplified to a considerable extent by the automation provided by CAM.

Perfect fabrication to measurements is a natural outcome. Even retailing via

advertising to prospective clients has become a lot easier. Viewing 3-D images

is always a handy tool for customers and manufacturers. Most packages are

ready-to-use, and no special technical training is essential. This enables

people on the shop floor to adapt to automated packages

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Application in Textile Manufacturing

The textile industry has seen a marked change owing to the mechanization

and computerization of various stages. The handloom sector has been

mechanized by CAD/CAM software that enables less monotony and more

productivity. The power loom and design sector too has benefited to a great

extent. Color combinations on fabrics and choice-of-material considerations,

coupled with R&D innovations, leading to novel designs, have been wonderful

outcomes. From knitwear to usual shawl and mat fabrications, software has

influenced all areas of textile

Application in Knitwear

Knitwear is an essentially unexplored area as far as CAD/CAM application

goes. A greater level of sophistication is needed, owing to complex design

parameters, unlike in areas such as architecture, where design would use

only simple geometric shapes. In knitwear design, the complexity of

patchwork manipulation and visualization would involve a greater level of

computing capability. However, this only goes to highlight the prominence

that CAD/CAM could occupy in the days to come. Considerable research on

the academic and industrial fronts is in progress.

Future Trends

Like all manufacturing and design areas, the textile industry too has profited a

great deal from CAD/CAM. Better efficiency in color selections and, more

importantly, memory storage for future use are great benefits. It is quite

beyond any doubt that in times to come, several other path-breaking

modifications like better target matching and reduced timeframes would be

achieved by computerized packages.

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NUMBERS OF SOFTWARE IN CAD CAM

The CAD software is very useful for the apparel industry. However, most of

the CAD software is very expensive; hence many professionals are on a look

or free CAD software. Some CAD CAM software is:

GERBER AND LECTRA

The “big daddies” of the apparel CAD software companies are Gerber and

Lectra. The two companies are Gerber Technology is based in the United

States and Lectra in Europe.

Both of these companies offer basic pattern making, grading, marker, product

data management, 3-D modeling, textile design and more. Gerber and Lectra

have products for the automotive, upholstery, and even shoe industries. They

further offer some of the best spreading and cutting machines available. If you

are ever able to view a demonstration of their products, you will be blown

away by the technology that is available.

TUKATECH

Tuka Tech is a relative newcomer to the apparel CAD market, and yet they

have a very strong product offering that is quickly being adopted by small

design companies. They offer all of the same types of products as Gerber and

Lectra, such as patternmaking (2D and 3D), grading, marker, and textile

design. In addition, they offer a collection of dress forms that mimic natural

skin.

PAD

PAD System offers a modular approach to its array of CAD/CAM solutions for

students, pattern makers and manufacturers of all sizes to build the system

appropriate to their needs. PAD has a unique 2 view layout which consists of

Plan view; where your initial patterns are created and graded, and Pieces

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view, where the patterns are finished and seam allowances are added by

single seam or globally.

OPTITEX'S

OptiTex develops innovative, user-friendly 2D and 3D CAD software for all

cut-fabric and fashion-related industries. OptiTex's fashion design software

solutions are designed to facilitate collaboration among partners throughout

the manufacturing process. OptiTex is also active in e-commerce, providing

online sales tools to promote branding and customer loyalty. As the industry

standard, OptiTex is a cornerstone of design training with installations in

universities and educational centers worldwide. OptiTex products are sold

and supported around the world through certified distributors and OEMs.

WILD GINGER

A company geared toward home sewers, custom clothiers and start ups, Wild

Ginger has a suite of modules for pattern making. While the company has

several kinds of products, most of them are pattern printing programs

designed for enthusiasts rather than pattern making programs.

AUDACES

Audaces Apparel makes the apparel production process more agile by

managing the steps of pattern design, grading, marker marking and plotting.

The creation of hems, darts, button marks; measure checking and grading of

patterns are some of the software's countless resources.

Apparel generates markers for cutting patterns, this process is automatic and

has two important advantages over the manual process: the first is in the

saving of fabric, since the system reduces waste; the second is the time saved

in the preparation of markers, which is reduced by 90%.

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About CAD Software Garber

Gerber Technology (www.gerbertechnology.com), a Microsoft Gold Certified

Partner, develops and manufactures the world's leading brands of product

lifecycle management (PLM) solutions, product data management (PDM)

solutions and CAD/CAM automation systems for the sewn products and

flexible materials industries. These systems automate and significantly

improve the efficiency of information management, product design and

development, pre-production and production processes. The company offers

specialized solutions to a variety of end-user markets including apparel,

composites, industrial fabrics, transportation interiors and home textiles.

Gerber Technology’s world headquarters are located in Tolland, Connecticut,

U.S.A. with regional offices, agents and distributors in more than 126

countries serving over 22,000 customers through 16 Customer Solutions

Centers on six continents. The company engineers and manufactures its

products in various locations throughout the United States, Europe and Asia.

Through innovation and commitment to our customers, Gerber’s products

have become industry standards as well as benchmarks by which all others

are measured. By continuing to explore emerging technologies and to build

strategic relationships, Gerber will continue to set the pace for new

innovation and productivity standards.

Gerber Technology unit of $530 million corporation Gerber Scientific, Inc.,

develops and manufactures the world's leading brands of integrated software

and hardware automation systems for the sewn products and flexible

materials industries. These systems automate and significantly improve the

efficiency of information management, product design and development, pre-

production, and production processes. The company offers specialized

solutions to a variety of end-user markets including apparel, transportation

interiors, furniture, composites and industrial fabrics. Gerber Technology’s

world headquarters are located in Tolland, Connecticut, U.S.A. with regional

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offices, agents and distributors in 125 countries serving a total of over 17,500

customers through seven Customer Solutions Centers on six continents. The

company engineers and manufactures its products in various locations in the

United States, Europe and Asia.

Established in 1968, Gerber Technology is one of four businesses of Gerber

Scientific, Inc. (www.gerberscientific.com) of South Windsor, Connecticut,

U.S.A., a corporation listed on the New York Stock Exchange under the “GRB”

symbol.

Make the most of your time and material. Speed up pattern design.

Create new patterns or modify existing ones. No need to start

from scratch every time.

Performs multiple operations simultaneously.

Automatically applies pattern modifications to all related pieces.

Select from more than 20 different automatic seam corners.

Accelerate marker making and save fabric.

Batch process jobs to maximize and streamline throughput.

View material usage as you make the marker.

Flip and rotate pieces with easy-to-use tools to maximize marker

efficiency.

Substitute sizes in markers and automatically generate new

ones.

Combine one or more markers to optimize cutting capacity.

Maximize productivity with the ability to use either mouse or

keyboard functions.

Improve data management and communication.

Utilizes sophisticated search tools for data management.

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Easily input hard patterns from digitizer.

Import and export marker data to a wide range of CAD systems.

Email pattern data to business partners.

Customize toolbars and get on-line help.

Drive cutting processes.

Define cutting path for automatic cutters to minimize dry haul. °

View cut path of pieces and define start points. ° Control cut

direction on mirrored pieces.

About CAD Software Lectra

Lectra is the world leader in integrated technology solutions—software,

CAD/CAM equipment and associated services— specifically for industries

using textiles, leather, industrial fabrics and composites to manufacture their

products. It caters for major world markets such as fashion, automotive and

furniture, as well as a broad array of other industries including as the

aeronautical and marine industries, wind power, and personal protective

equipment. A transnational company, Lectra serves 23,000 customers in

more than 100 countries, developing long-term relationships. With its state-

of-the-art technology, which meets the specific needs of each industry, and

the expertise of its 1,400 employees, Lectra sets the standard in its field.

Lectra’s solutions enable customers to automate, streamline and accelerate

product design, development and manufacturing. For the fashion industry,

they also facilitate the planning and management of the entire collection

lifecycle. Established in 1973 and based in France, Lectra is listed on Euronext

Paris.

Lectra’s strength lies in its capacity to provide integrated technological

solutions (CAD/CAM software and equipment, and related services) specially

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designed for the fashion, automotive and furniture industries and other

industries using industrial and composite materials.

Digitizer Board and how it is related to CAD

Digitizer is made for "digitizing" paper plans, electronic plans or satellite

images. It allows you to use a drawing as a template. By simply clicking on the

corners of the roof outline, then clicking to add all the drains, vents, curbs and

other roof top items you can produce a professional drawing and takeoff in

minutes. The more "cut up" the roof the faster you will be compared to the

manual takeoff method.

Digitizer runs on the same platform as our Roof CAD module. So the end

result is the same great drawing and the same great takeoff information. It

can be run on its own or combined with Roof CAD for the ultimate roof

takeoff tool! When combined with Roof CAD you gain the ability to create

drawings from rough sketches, create detail drawings, jazz up your drawings

with photos, arrows and more

An input device that enables you to enter drawings and sketches into

a computer. A digitizing tablet consists of an electronic tablet and a cursor or

pen. A cursor (called also a puck) is similar to a mouse, except that it has a

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window with cross hairs for pin point placement, and it can have as many as

16 buttons. A pen looks like a simple ballpoint pen but uses an electronic

head instead of ink. The tablet contains electronics that enable it to detect

movement of the cursor or pen and translate the movements

into digital signals that it sends to the computer.

For digitizing tablets, each point on the tablet represents a point on

the display screen in a fixed manner. This differs from mice, in which all

movement is relative to the current cursor position. The static nature of

digitizing tablets makes them particularly effective for tracing drawings. Most

modern digitizing tablets also support a mouse emulation mode, in which the

pen or cursor acts like a mouse.

Digitizing tablets are also called digitizers, graphics tablets, touch tablets, or

simply tablets.

Plotter and how it is related to CAM

One of the very best series of CAD plotters is HP, and you can find them in

abundance and for very affordable prices. Two creams of the crop plotters for

those professionals interested in the highest quality engineering CAD

drawings are the HP Design Jet 1050 and 1055. Both of these are available at

this user-friendly and comprehensive site. The HP 1050 can be fitted with an

aftermarket RIP, and the 1055 model actually comes already integrated with

one.

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Other fine HP CAD plotters include the 500, 800, and 5000. They all promise

high resolution, precision, and speed--requisite qualities for top tier CAD

plotters. Nevertheless, Hewlett-Packard is not the only excellent designer of

plotters with CAD capabilities.

Another company that provides sophisticated and cutting-edge CAD plotters

is Encad, and you can also find one of their most advanced models. One such

model is the Encad T-200, which is actually the only Encad plotter that can

print CAD images in addition to full color photographic images. You will come

to appreciate that kind of versatility.

About CAM

Computer-aided manufacturing (CAM) is the use of computer-based software

tools that assist engineers and machinists in manufacturing or prototyping

product components. CAM is a programming tool that makes it possible to

manufacture physical models using computer-aided design (CAD) programs.

CAM creates real life versions of components designed within a software

package. In 1970’s it made an entry in the Textile and Apparel industry.

CAM is the next computer-aided process after computer-aided design (CAD),

as the model generated in CAD can be input into CAM software, which then

controls the machine tool

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Different Type Of CAD CAM Machines

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Importance of CAD/ CAM in Garment Industry

There are three functions to CAD software that revolutionized the design

industry: multi-dimensional images, computer animation, and computational

geometry. Multi-dimensional images need curves, surfaces and solids, all of

which are very difficult to create on a computer screen. The physical drawing

of these shapes requires art training and the use of shading to indicate other

dimensions.

CAD software allows the images to be rotated 360 degrees, providing

designers with the opportunity to model the entire object much faster and

without the need to physically render the item first. The computer

animation aspect has impacted both the entertainment in industry. In

entertainment, it has allowed the development of higher quality cartoons and

commercials. Both the form and function can be modeled and any designer

flaws can be seen and corrected, before the creation of a physical prototype.

Computational geometry and industrial art have also capitalized on the

functions available in this tool to create a new type of sophisticated product

that better suits their unique needs.

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The adoption of CAD software resulted in the elimination of a large number of

drafting and designer jobs. Entire departments could be replaced with one

software package.

Over time, a new role of CAD designer has developed. This person has an

advanced skill level with the software and may act as an adviser to other

designers and engineers.

Specialized courses in specific software and advance functions are available

on a part-time basis at a wide range of community and career colleges. It is

very important to keep these skills updated, as the software is constantly

upgraded and changes over time.

The price of CAD software has dropped significantly as the usage increased

and the size of computer memory expanded. The software now offers

complex, highly advanced features for the same price as the base version

three years ago. These tools have allowed designed to test out new theories

and explore options before continuing.

By using CAD the professional designers can do the designing work faster

thus the firm’s overall requirement of the number of designers reduces. This

helps the company to maintain competitive edge in the market where the

trend is towards low cost and high quality products. Since the productivity of

the designer is increased the company can carry out the changes in the

products faster and bring them into the market faster before the competition.

There are number of factors that decide the increase in productivity by using

CAD compared to using traditional designing process. These factors are:-

How complex the engineering drawing is: For highly complex drawings

the traditional drawing process consumes lots of time.

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The details required in the drawing: If more details are required, it can

be done much faster with CAD.

The number of repeated parts in the drawings: There is a feature of

saving the repeated drawings in CAD software and they can be used in

any other drawing without having to draw them again. There is also

library feature in CAD software, where a number of readymade

drawings of most frequently used components are available readily.

Symmetry required in the drawing: The symmetry feature in the CAD

software helps drawing symmetrical parts faster.

On the whole, all these factors lead to increase in productivity of the designer.

Due to lesser time required in drawing the designer feels lesser stress, which

indirectly leads to further increase in the productivity of the designer.

Conclusion

CAD/CAM is taking the textile industry by storm. The benefits of CAD/CAM

applications are being recognized by the industry, and are gradually gaining

acceptance. This article seeks to study in detail the revolution of CAD/CAM in

the textile industry, briefly tracing its evolution and then dwelling briefly on

current applications and future possibilities.

CAD/CAM is currently in use in several industries such as architecture,

electronics, mechanical and production engineering and textiles. There are

several kinds of CAD packages available in the market today, with different

kinds of features. Most of the packages are ready-to-use with a number of

graphics, which the user can select according to his or her requirements. User

friendly and requirement-compatible environments being embedded are a

clear merit, enabling easy usage.

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With the advent of large-scale computer usage, there increased the demand

for design packages such as CAD for the twin purpose of beating the

monotony of paper-based engineering design and to speed up design and

production timeframes. With miniaturization of computers and electronics

and powerful memory features, CAD/CAM has now attained great heights, as

far as industrial application goes.