1. Bangladesh University of Business & Technology (BUBT)
Course Code: TXE-317
An Assignment on CAD Systems in textile.
Submitted by
Name: Anik Kumar Das
ID.: 12132107053
Intake: 8th
Section: 2
2. CAD Systems for Apparel Industry
Computer Aided Design (CAD) becomes an essential tool for pattern
makingand related jobs in garment industry. In apparel industry CAD
Software is used for pattern making,Grading of pattern, marker making
and digitizingmanual patterns.
There are number of CAD software suppliers who have developed CAD
systems. But only few names are popular in fashion industry.
CAD systems in the apparel industry:
AccuMark Pattern Design Software by Gerber Technology:
CAD.Assyst by Human Solution Assyst AVM
Modaris by Lectra Systems
Optitex Pattern Design software by Optitex
TUKAcad by Tukateck Inc.
Fashion Cad by Cad CamSolutions Australia Pty. Ltd
SDS-ONE APEX3 fromShima Seiki
PAD System
GT CAD by Genuine Technology and ResearchLimited.
3. Classification of 3D CAD System:
1. 3D modeling and 2D pattern unwrapping.
2. 3D simulation of 2D patterns.
3. 2D sketch-based 3D simulation.
4. Combined Techniques.
5. Reactive 2D/3D design technique.
6. Digital draping.
Advantages of CAD
This easy to operate designing system- CAD, has many advantages.
o The expense and time is reduced in a considerable manner when compared to
the laborious manual work of designing.
o Designing can be done from anywhere as the customers are able to control the
process from remote locations as well.
o The data can be easily stored, transmitted, and transported through computer
files.
o Digital swatches can be saved on floppy disks, zip disks, CD-ROM or hard drive
thus saving space. Moreover they can be easily organized for fast and easy
retrieval.
o The designs can be easily customized and personalized as corrections and
editing can be done at any time without significant delays or cost increases.
o The designers don't need to produce swatches all the time as they can now see
how a particular fabric or garment looks in different colors and shapes on
computer screen itself.
With all its benefits, care too has to be taken before going for any CAD
software. The softwares which are supported by the available hardwares should
only be purchased or the hardware should be upgraded to comply with the new
software. Training too has to be given to the people who are going to operate
the system so that maximum benefit may be taken from it. With careful
selection and trained professionals, the textile industry can enjoy the benefits
of the IT revolution right at their door.
4. Why CAD/CAM Is Necessary
Today every coming generation is more fashion conscious so there is huge demand for
new-fangled weave designs. With these conditions designers have difficulty in keeping
pace with the fast changing trends of the market. Some times they find that they are not
ready to cater the market needs. It is not easy to them to remain competitive, by merely
depending upon the traditional way of designing, because todays design becomes out of
fashion tomorrow. Hence they loose a share of market, so to keeping pace with fast
shifting trends of market computer aided designing and manufacturing is very much
required.
It is well known phenomenon that human being is always in search of opportunities
related to saving money, time and comfort. Any textile industry will think in terms of
improving the efficiency, maximum utilization of resources and improvement in services
for customers satisfaction. Search of these elements leads towards development and use
of new technologies. As the proverb says "Creativity is one percent inspiration and
ninety-nine per cent perspiration." but computers have confirm it wrong. They have
made textile designing simpler, faster, more precise and enjoyable. The designer can
create his motifs with a mouse or pen. Once the design is created, further process of
editing the design i.e. clipping of certain parts, adding new shapes, changing the shapes,
distortion, resizing, recolouration, color reduction, replicating and combining as per the
need can be done at the minimum possible time. Also, one part of design can be altered
without affecting the rest.
Manual vs CAD/CAM system in garment industry
Greater flexibility in pattern designing, grading and marking, reduction in waste %, increase
in quality of cutting room and reduction in sample making time are some of the benefits of
application of CAD/CAM system in garment manufacturing, asserts V Parthasarathi.
Textiles and computers are genetically related. It is so
because computers are believed to be from punch card
system used in jacquard weaving machine. In the
environment, where computer is a normal need for every
industry, textile industry is no exception. Textile companies
that continue to excel in today's competitive business climate
understand the importance of computers.
After more than a decade of computer revolution, some
textile corporates in India have understood the dire need of
the “IT EVOLUTION”. Most of the Indian industries have
not come under the influence of this evolution. The ability to
withstand the revolution in science for several decades has enabled computers to be used
very much as an effective tool in information technology and communication fields.
5. In international and domestic boom in the last few years, the fashion designing industry is
riding the crest of wave of success. Fashion designers are mushrooming, their earnings are
rising, and promotions are coming at a very faster rate. The direct employment in the fashion
sector is running into millions. Textiles are India's single largest foreign exchange earner
contributing to about one third of total export. In addition India's share in the world market
with regard to leather are significant. It is certain that job and business opportunities in the
fashion trade are likely to grow at higher rates.
CAD & CAM are a part of computer technology. Increased competitiveness and demand for
shorter lead times has lead to the slow, but definite proliferation of CAD/CAM systems in
India, even in the textile and apparel industry. Traditional working methods are being phased
out in favour of futuristic and globally prevalent methods of working. The evolution in
technology has been influenced by the proposition to reduce cost and lead time, to increase
interactivity between what is real and virtual and to enhance one's creative abilities. This
article is a part of the author's research work -- a comparison of CAD/CAM & Manual
systems in garment manufacturing -- reveals the advantage of CAD/CAM system over
manual approach in the garment industry.
Experimental procedure and results
In order to assess the improvement in productivity and quality, CAD/CAM manufacturing is
compared to Manual manufacturing processes. Various work processes followed in
CAD/CAM (Unit C) and MANUAL (Unit M) are discussed and the results are provided
below.
The following are the key areas where the
author makes his observation:
• Time required in pattern designing, grading, pattern
alteration. • Waste percentage in cutting room.
• Quality of cutting.
• Time taken for sample making.
• Productivity.
• Lead time for production.
A common sort, which was processed in both
units was
considered for
the
observation,
and so it was decided to compare men's shirt
(size L) (casual wear, long sleeve) with the
following dimension:
Results of the experiment
Time required in pattern designing, grading,
pattern alteration:
Both in unit C and unit M the time required
6. for preparing a sort of the above said dimension was observed. Particular time required for
each operation was observed, by using the stopwatch and six sets of reading were taken. The
average time taken is mentioned above.
Time taken for the following activities in CAD/CAM System:
Time taken for the following activities in manual system:
Comparison between the unit C & unit M:
7. Waste percentage in cutting operation
In order to determine waste percentage in both manual and CAD/CAM system, following
observations were made. The fabric consumption for 500 shirts was determined by taking the
dimension of centre size, ie, ‘L’ the area of front, back and sleeve part of shirt is taken for 'L'
size shirt. The fabric required is 2.15 metres without tolerance. With tolerance, the fabric
required is 2.4 metres.
Total no of shirts observed = 500
Fabric required for 500 shirts = 500 X 2.42
= 1209.06 mts
= 1210 mts
No of shirts made out from 1210 metres with (90% fabric realisation) in CAD/CAM system:
= (1210 X 90) 1100
= 1089 mts.
= 1089/2.42
No of shirts = 450
No of shirts made out from 1210 metres with (80% fabric realisation) in MANUAL system:
= (1210 X 80) /100
= 968 mts
= 968/2.42
No of shirts - 403
This exhibits a fabric saving of 10% by CAD/CAM system over MANUAL system as shown
by the following Table:
Quality of cutting:
In order to determine the quality of cutting,
10 rolls from 100 rolls of cloth were received
both in cutting and sewing department. It was
observed every day. Amount of rejected
garment was collected taking into
consideration the following quality
particulars:
• Fabric defects.
• All components cut on the correct grain lines and in accordance with the pile direction of
the fabric.
• Dimensionally accurate garment that do not exceed specified tolerance.
• All materials spread at correct tension to prevent under- or over-sized component and/or
garment.
• Consistent and accurate marking.
Quality of cutting in Unit – C
8. Quality of cutting in UNIT – M
Time taken for sample making
Sample making is a continuous process in clothing industry during the development of a new
product. The following steps are involved in the process:
1. New material, design and processes have to be identified.
2. The production of garment patterns has to be altered and perfected to rectify faults during
making up of the sample.
3. At the sample stage, the quantities of fabric and trimming are established and quick
costing is made.
4. The finished garment sample has to undergo scrutiny to evaluate whether they fit in the
viability of producing the garment.
In order to determine sample-making time, the author followed the process of sample making
9. in both units. The following was the time taken:
Productivity:
Productivity of Unit C & Unit M was obtained by
taking into account per day production and monthly
production
capacity when
similar sorts
of garment
were
produced. The
number of
finished
garment
obtained each day as observed were as follows:
Per day productivity (Unit C) = 15,856 pieces
Per day productivity (Unit M)
= 4,013 pieces
Lead time for production:
A typical product
development cycle of a
garment industry consists of
the following steps:
• Designing
• Marketing
• Purchasing/production.
One has to compare lead-time
of garment, taking into
consideration the above-
mentioned procedure in both Unit C and Unit M. The
observed time required for each stage of procedure,
details of the time taken in the two units are as
follows:
Lead time for Unit C = 39 Days
Lead time for Unit M = 55 Days
Results and discussion
Time reduction in CAD for pattern designing,
grading and marking:
As mentioned in the experimental procedure, the
CAD/CAM system takes 36.81 minutes, whereas
MANUAL system takes 350 minutes. By this, one
can say that the MANUAL system takes nearly 10
times of the time taken by the CAD/CAM system.
MANUAL system takes comparatively much more
10. time because of: New Pattern Creation, Measurement of Marking, Pattern Grading, Marker
Planning, Sketching, etc. These activities are done only by an individual and so the time
taken depends on the skill of the person.
TUKA DESIGN Software in Unit C uses powerful CAD tools to draft pattern, which gives
them unlimited saving in time compared to the manual method used in the Unit M. A
previously constructed pattern in the system can be used as the base pattern for a new style.
Waste percentage in cutting room:
With the use of CAD/CAM system through experimental procedure it can be observed that
about 10% of material is saved, as compared to the manual method. This is achieved due to
the following reason:
1. Do not cut until a trial layout shows the best location for all pieces within minimum length
of cloth.
2. Place all pattern pieces close together, so as to reduce the waste % of the cloth.
3. Spreading waste is considerably reduced due to correct length spreading, remnants are also
reduced by TUKA SPREAD machine. Since the CAD/CAM system has mathematical
algorithms in-built in CAD System, this ensures the most economical use of material.
Quality of cutting:
As mentioned in the experimental procedure, the CAD/CAM
system has 0.38% of the waste reduction whereas MANUAL
System has l.03%. This shows that quality is very good in
CAD/CAM because, the spreading of fabric is done by the
TUKA spreading machine, where the 'Photo Electric Guides'
are used to maintain uniform tension in the fabric, so that
creases in the fabric is avoided during spreading, whereas in
the MANUAL system it is unavoidable. Tuka Tech Cutter
has an automatic sharpening device for knife, and raw-edge
of the fabric do not fray out; As in manual cutting, which
happens due to imperfect sharpening of knife.
Time taken for sample making:
In Unit C using TUKA CAD Software and ENCAD: CROMA 24, Plotter it is easy to make
sample. Sample making time was observed to be around 5 days for Unit C and about 10 days
for Unit M. The CAD software helps designer of pattern to alter it easily in quick time. This
is mainly due to collection planning CAD Software, which helps in:
• Developing the variation from core design.
• Trying the same cloth on a number of different designs.
• Modifying some of the ideas to make the garment more acceptable to a wider range of
customer.
With this flexible CAD System and plotte,r Unit C is able to reduce 50% of sample making
time compared to Unit M.
Productivity:
11. As mentioned in the experimental procedure, the CAD/CAM System has a production of
15,856 pieces/day whereas the MANUAL system has 4,013 pieces/day.
• As the CAD/CAM process requires transfer of information or data for marker planning via
floppy, the process is simplified and the production is increased.
• In CAD/CAM system, the capacity of the cutting room has to deal with a mixture of
different types of cloth. Whereas in MANUAL system it is highly impossible to work with
mixture of different types of cloth.
• With such a flexible cutting room facilities available, Unit C must have higher production
rates compared with Unit M member together with very high cutting speed.
Lead time for production:
Lead-time of garment production is the number of days
required to finish a garment from sample stage to finished
garment. Lead-time of Unit C is about 39 days and of Unit M
is around 55 days. Due to faster sample production, highly
saved time and higher productivity combined with flexibility,
CAD system Unit C is more acceptable.
Conclusion
Unit C is using CAD/CAM system for garment
manufacturing. There is a significant improvement in
productivity, and quality, leading to time reduction. The
following are the some of the benefits of CAD/CAM that the
author observed from the Unit C.
• Reduction in pattern designing, grading, and pattern alteration time by around 90%. The
time required for Unit C is 36.81 minutes and for line M is about 350 minutes.
• Greater flexibility in pattern designing, grading and marking
• Reduction in waste% of up to 10%.
• Increasing quality of cutting room by around 50%.
• Reduction in sample making time by 60%.
Unit C ---- 5 days
Unit M ---- 10 days
• Increasing monthly productivity by 75%.
Productivity/day (Unit C) -15,856
Productivity/day (Unit M) - 4,013
• Reduction in lead-time up to 45 days.
Unit C ----- 39 days
Unit M ---- 55 days
References
1. www.lectra.com.
2. www.tukatech.com.
3. www.fashionflame.com.
4. www.gerber.com.
5. Gerry C: Introduction to Clothing Manufacture, Blackwell Science (London) 1991.
6. Pooja Gupta: Evolution of Design Solutions in the Textile and Apparel Industry,