Bangladesh University of Business & Technology (BUBT)

Course Code: TXE-317

An Assignment on CAD Systems in textile.

Submitted byName: Anik Kumar DasID.: 12132107053Intake: 8th Section: 2

CAD Systems for Apparel IndustryComputer Aided Design (CAD) becomes an essential tool for pattern making and related jobs in garment industry. In apparel industry CAD Software is used for pattern making, Grading of pattern, marker making and digitizing manual 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 SoftwarebyGerber Technology:

CAD.Assystby Human Solution Assyst AVM

Modaris byLectra Systems

Optitex Pattern Design softwareby Optitex

TUKAcadby Tukateck Inc.

Fashion Cadby Cad Cam Solutions Australia Pty. Ltd

SDS-ONE APEX3from Shima Seiki

PAD System

GT CADby Genuine Technology and Research Limited.

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 CADThis easy to operate designing system- CAD, has many advantages. The expense and time is reduced in a considerable manner when compared to the laborious manual work of designing. Designing can be done from anywhere as the customers are able to control the process from remote locations as well. The data can be easily stored, transmitted, and transported through computer files. 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. The designs can be easily customized and personalized as corrections and editing can be done at any time without significant delays or cost increases. 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.

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.

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 resultsIn 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 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:Waste percentage in cutting operationIn 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 = 500Fabric 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.= 1089/2.42No of shirts = 450

No of shirts made out from 1210 metres with (80% fabric realisation) in MANUAL system:= (1210 X 80) /100= 968 mts= 968/2.42No of shirts - 403This 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 CQuality of cutting in UNIT MTime taken for sample makingSample 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 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 piecesLead 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 DaysLead time for Unit M = 55 DaysResults and discussionTime 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 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: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.

ConclusionUnit 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 daysUnit M ---- 10 days Increasing monthly productivity by 75%.Productivity/day (Unit C) -15,856Productivity/day (Unit M) - 4,013 Reduction in lead-time up to 45 days.Unit C ----- 39 daysUnit M ---- 55 daysReferences1. 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, Clothesline, Vol 14.