NEHRU ARTS AND SCIENCE COLLEGE
THIRUMALAYAMPALAYAM -COIMBATORE
DEPARTMENT OF COSTUME DESIGN AND FASHION
STUDY MATERIAL
COURSE
: III-B.SC (CDF)
SEMESTER
: V
SUBJECT
: COMPUTERS IN GARMENT INDUSTRY
UNIT
: I
LECTURER NAME
: V.S.KARPAGAVALLI
Part- A
1. Types of storage devices are input devices, output devices.
2. The analog systems carry out arithmetic and logical operations.
3. Digital computing machines when clubbed with Analog computers produce Hybrid
4.
5.
6.
7.
8.
9.
10.
computers.
The advantage of an analog computer is that it can simultaneously find solutions to
several .
Digital Computers are that kind of computing machines which work on the principle of
binary mathematics.
General purpose computers are versatile and process business data as really as they
process complex mathematical formulas.
Mainframes are computers that are the most bulky types.
Minicomputers are used by business organization.
A single Byte is a group of 8 numbers or bits represented through a code series
comprising of “0” and “1”.
Special purpose computers are often used as simulator.
Part- B
 Briefly explain the classification of the computers.
Classification of computers, computer generations, computer specification, organization of computer
sections. Types of storage devices (Primary and secondary), input devices, output devices.
Classification of Computers
Based on the purpose, models available computers can be classified as
1. Analog and digital computers
2. Hybrid computers
3. General purpose and special purpose computers.
Analog Computers
The analog systems carry out arithmetic and logical operations by manipulating and
processing data which you input such as the weight, temperature, voltage, power density,
etc. But unlike the digital computer that changes all inputs to binary digits of “1” and “0”,
the analog computer does not change inputted data to any such sign language.
The analog computer has become obsolete type of computer these days. It is different from
a digital computer as it can perform numerous mathematical operations simultaneously. The
digital computers, however could not operate the more complex operations. The Analog
System is also unique in terms of operation as it utilizes continuous variables for the purpose
of mathematical computation. It utilizes mechanical, hydraulic, or electrical energy or
operation.
Mathematical Principles Applied For The Data Processing In Analog Computers:






Logarithm
Summation
Exponentiation
Calculus
Multiplication and Division
Inversion
The analog computer which is a complex machine is an integration of various mechanical
parts which has pipes, valves, levers, gears and several key parts which can be named as
follows:

Fixed function generators
Operational amplifiers


Potentiometers
Integrators
Advantages and Disadvantages of Analog Computers
The advantage of an analog computer is that it can simultaneously find solutions to several
mathematical problems and that too while being precise unlike the digital computer. But it is
not free of drawbacks. Unlike the digital computer it lacks speed of calculation. There are
other functional problems which mar the efficiency of analog systems. Of these, the
problems of non-linearities, temperature co-efficient, parasitic effects and noise floor are
the main problems so to say.
Digital Computers
Digital Computers are that kind of computing machines which work on the principle of
binary mathematics. Digital computing machines when clubbed with Analog computers
produce Hybrid computers. The digital systems work on the principle of binary mathematics.
In binary mathematics all calculations are represented through “0” and “1”.
You have often heard about the word “Byte”, “Mega Byte”, “Kilo Byte”. But what is a Byte?
A single Byte is a group of 8 numbers or bits represented through a code series comprising
of “0” and “1” .The combination of the digital signal can solve a number of mathematical
operations. It is interesting to note that the fundamentals of mathematics applied are
addition, subtraction, multiplication and division. But the chief problem is that though it can
solve mathematical problems at a tremendous speed, it cannot perform bulk operations
simultaneously. For this purpose, digital systems by themselves cannot give very precise
results. Hence, for greater efficiency, the Digital systems do not find much application.
Data Processing In Digital Computers Digital computers function with the help of logic
circuits. A reliable oscillator helps in the proper synchronization of various logic circuits that
are responsible for processing data in the digital computers. In better quality computers, the
oscillation rate might even be a billion cycles per second. Operating at such high speed, it can
process more than billions of logic and arithmetic problems.
A digital computer with the help of binary system cannot only perform mathematical
problems but also combine the bytes to produce desired graphics, sounds, images and other
such commands.
Hybrid Computers
These types of computers are, as the name suggests, a combination of both Analog and
Digital computers. The Digital computers which work on the principle of binary digit system
of “0” and “1” can give very precise results. But the problem is that they are too slow and
incapable of large scale mathematical operation. In the hybrid types of computers the Digital
counterparts convert the analog signals to perform Robotics and Process control.
General and Special Purpose computers
General purpose computers are versatile and process business data as really as they
process complex mathematical formulas. It can store large amount of data and the programs
necessary to process them. Special purpose computers incorporated many features of general
purpose computer but support highly specialized data processing task. Special purpose
computers designed to handle specific problems and are not applied to other computerized
activities. Special purpose computers are often used as simulator. A simulator is a computer
controlled device for training people under simulated or artificially created conditions. Ex.
Aircraft industry use simulator to train pilots and flight crews in fully equipped and computer
controller.
 Briefly explain the classification of computer based on its Capacity, Speed and
Reliability.
Classification Based on Capacity, Speed and Reliability of Computers
They are classified as below – Mainframe computers, Minicomputers,
Microcomputers, Super computers and Workstations
Mainframes





Mainframes are computers that are the most bulky types and with the advancement
of technology, they have almost become extinct.
Mainframe computer systems can be called the predecessor of servers because they
could actually support multi users though as efficiently as the servers.
Usually, a main frame would occupy an entire room and could cost over million
dollars.
Used for the purpose of research, engineering works, meteorological calculations,
graphics and the likes, mainframes today constitutes Unix, Linux, and IBM's z/OS,
OS/390, MVS, VM, and VSE.
Mainframe systems were manufactured extensively throughout the 1950s and were
marketed by IBM, Control Data, General Electric, NCR, UNIVAC, Honeywell, RC, and
Burroughs.
The three important Features of mainframe Computers:



Mainframes provide for maximum I/O connectivity as they accommodate huge disc
farms.
Mainframes excel in providing maximum I/O band width. Interestingly in spite of all
the connected drives connected to the mainframe system, no data blocking ever
happens to mar its efficiency.
Mainframe systems also provide for very good single thread operations.
Mainframe computer (this IBM z-series computer is about 6 feet tall)
Minicomputers
The Mini computers are a less bulky version of the mainframe computers. Minicomputers
are used by business organization. The difference being that it can support the simultaneous
working of up to 100 users and is usually maintained in business organizations for the
maintenance of accounts and finances. Minicomputers, what exactly are they? If supercomputers
and mainframes are considered to be the best in terms of mathematical operations then
minicomputer systems succeed them. Previously, minicomputers were considered to be superior
to personal systems. But these days, advancement in technology has made minicomputers
almost obsolete because the PCs today are highly advanced.
The Minicomputers were first built in 1960s and they immediately became a huge success as
40,000 of the minicomputer systems were immediately sold of making the computers hugely
available to the general public. With such a successful market possibility many companies
stepped in to venture in the minicomputer market. The most successful among these two
hundred companies was DEC that launched the minicomputer models PDP-11 and VAX 11/780.
Some significant aspects and historical facts about the mini computer system has been
summarized as follows:




They are much smaller in size than the mainframe computer systems. As such they do
not occupy an entire room but usually occupy space similar in size to that of a standard
refrigerator.
They are much less expensive than the mainframes.
Their invention was possible because of the invention of core memory technologies and
transistors.
Minicomputers can give parallel access to up to 100 users. Hence they were used in
places such as business organizations for maintaining billings and finances.
Some of the very first companies to manufacture the minicomputer systems were Hewlett
Packard, DEC and Data General.
A few models of minicomputers which have been a marked success over the years are:









DEC VAX series and PDP series
Hewlett Packard HP3000 series
SDS,SDS-92
Prime Computers, Prime 50 Series
Norsk Data, Nord-1, Nord-10, Nord-100
IBM Midrange Computers
Control Data Corporation's CDC 160A, CDC-1700
Data General Nova
Honeywell-Bull Level 6/DPS Level6/DPS 6000 series
Minicomputers have eventually evolved in to microcomputers. With the launch of
microcomputers, the public have had a greater access to the advantage of incorporating
computers in the daily stride of their lives.
Micro Computers
Besides, there are personal computers or microcomputers. The micro computers include
Desktop PC s, Laptops, Handheld computers, Tablet PC s, workstations, palmtops, etc. These
are the most frequently used computers.
A microcomputer is a computer that has a microprocessor chip as its CPU. They are often called
personal computers because they are designed to be used by one person at a time. Personal
computers are typically used at home, at school, or at a business. Popular uses for
microcomputers include word processing, surfing the web, sending and receiving e-mail,
spreadsheet calculations, database management, editing photographs, creating graphics, and
playing music or games. Personal computers come in two major varieties, desktop computers
and laptop computers:
Desktop Personal Computer
Palmtop computer
Laptop personal computer
Personal Digital Assistant
 What are Super Computers.
Supercomputers
A supercomputer is mainframe computer that has been optimized for speed and
processing power. The most famous series of supercomputers were designed by the company
founded and named after Seymour Cray. The Cray-1 was built in the 1976 and installed at Los
Alamos National Laboratory. Supercomputers are used for extremely calculation-intensive tasks
such simulating nuclear bomb detonations, aerodynamic flows, and global weather patterns. A
supercomputer typically costs several million dollars.
Recently, some supercomputers have been constructed by connecting together large numbers
of individual processing units (in some cases, these processing units are standard
microcomputer hardware).
Supercomputer (this one is a Cray-2 from the 1980’s)
Workstation computer
Workstations/Servers
A workstation is a powerful, high-end microcomputer. They contain one or more
microprocessor CPUs. They may be used by a single-user for applications requiring more power
than a typical PC (rendering complex graphics, or performing intensive scientific calculations).
Alternately, workstation-class microcomputers may be used as server computers that supply
files to client computers over a network. This class of powerful microcomputers can also be
used to handle the processing for many users simultaneously who are connected via terminals;
in this respect, high-end workstations have essentially supplanted the role of minicomputers
(see below).
GENERATION OF COMPUTERS
Generations of Computer
The history of computer development is often referred to in reference to the different
generations of computing devices A generation refers to the state of improvement in the
development of a product. This term is also used in the different advancements of computer
technology. With each new generation, the circuitry has gotten smaller and more advanced
than the previous generation before it. As a result of the miniaturization, speed, power, and
memory of computers have proportionally increased. New discoveries are constantly being
developed that affect the way we live, work and play.
Each generation of computer is characterized by a major technological development that
fundamentally changed the way computers operate, resulting in increasingly smaller, cheaper,
and more powerful and more efficient and reliable devices. Read about each generation and
the developments that led to the current devices that we use today.
First Generation - 1940-1956: Vacuum Tubes
The first computers used vacuum tubes for circuitry and magnetic drums for memory, and were
often enormous, taking up entire rooms. A magnetic drum, also referred to as drum, is a metal
cylinder coated with magnetic iron-oxide material on which data and programs can be stored.
Magnetic drums were once used as a primary storage device but have since been implemented
as auxiliary storage devices.
The tracks on a magnetic drum are assigned to channels located around the circumference of
the drum, forming adjacent circular bands that wind around the drum. Single drum can have up
to 200 tracks. As the drum rotates at a speed of up to 3,000 rpm, the device’s read/write heads
deposit magnetized spots on the drum during the write operation and sense these spots during
a read operation. This action is similar to that of a magnetic tape or disk drive.
They were very expensive to operate and in addition to using a great deal of electricity,
generated a lot of heat, which was often the cause of malfunctions. First generation computers
relied on machine language to perform operations, and they could only solve one problem at a
time. Machine languages are the only languages understood by computers. While easily
understood by computers, machine languages are almost impossible for humans to use
because they consist entirely of numbers. Programmers, therefore, use either a high-level
programming language or an assembly language. An assembly language contains the same
instructions as a machine language, but the instructions and variables have names instead of
being just numbers.
Programs written in high-level languages are translated into assembly language or machine
language by a compiler. Assembly language programs are translated into machine language by
a program called an assembler.
Every CPU has its own unique machine language. Programs must be rewritten or recompiled,
therefore, to run on different types of computers. Input was based on punched cards and paper
tape, and output was displayed on printouts.
The UNIVAC and ENIAC computers are examples of first-generation computing devices. The
UNIVAC was the first commercial computer delivered to a business client, the U.S. Census
Bureau in 1951.
Acronym for Electronic Numerical Integrator and Computer, the world's first operational
electronic digital computer, developed by Army Ordnance to compute World War II ballistic
firing tables. The ENIAC, weighing 30 tons, using 200 kilowatts of electric power and consisting
of 18,000 vacuum tubes, 1,500 relays, and hundreds of thousands of resistors, capacitors, and
inductors, was completed in 1945. In addition to ballistics, the ENIAC's field of application
included weather prediction, atomic-energy calculations, cosmic-ray studies, thermal ignition,
random-number studies, wind-tunnel design, and other scientific uses. The ENIAC soon became
obsolete as the need arose for faster computing speeds.
Second Generation - 1956-1963: Transistors
Transistors replaced vacuum tubes and ushered in the second generation of computers.
Transistor is a device composed of semiconductor material that amplifies a signal or opens or
closes a circuit. Invented in 1947at Bell Labs, transistors have become the key ingredient of all
digital circuits, including computers. Today's microprocessors contains tens of millions of
microscopic transistors.
Prior to the invention of transistors, digital circuits were composed of vacuum tubes, which had
many disadvantages. They were much larger, required more energy, dissipated more heat, and
were more prone to failures. It's safe to say that without the invention of transistors,
computing as we know it today would not be possible.
The transistor was invented in 1947 but did not see widespread use in computers until the late
50s. The transistor was far superior to the vacuum tube, allowing computers to become
smaller, faster, cheaper, more energy-efficient and more reliable than their first-generation
predecessors. Though the transistor still generated a great deal of heat that subjected the
computer to damage, it was a vast improvement over the vacuum tube. Second-generation
computers still relied on punched cards for input and printouts for output.
Second-generation computers moved from cryptic binary machine language to symbolic, or
assembly, languages, which allowed programmers to specify instructions in words. High-level
programming languages were also being developed at this time, such as early versions of
COBOL and FORTRAN. These were also the first computers that stored their instructions in their
memory, which moved from a magnetic drum to magnetic core technology.
The first computers of this generation were developed for the atomic energy industry.
Third Generation - 1964-1971: Integrated Circuits
The development of the integrated circuit was the hallmark of the third generation of
computers. Transistors were miniaturized and placed on silicon chips, called semiconductors,
which drastically increased the speed and efficiency of computers.
A nonmetallic chemical element in the carbon family of elements. Silicon - atomic symbol "Si" is the second most abundant element in the earth's crust, surpassed only by oxygen. Silicon
does not occur uncombined in nature. Sand and almost all rocks contain silicon combined with
oxygen, forming silica. When silicon combines with other elements, such as iron, aluminum or
potassium, a silicate is formed. Compounds of silicon also occur in the atmosphere, natural
waters, and many plants and in the bodies of some animals.
Silicon is the basic material used to make computer chips, transistors, silicon diodes and other
electronic circuits and switching devices because its atomic structure makes the element an
ideal semiconductor. Silicon is commonly doped, or mixed, with other elements, such as boron,
phosphorous and arsenic, to alter its conductive properties. A chip is a small piece of
semiconducting material (usually silicon) on which an integrated circuit is embedded. A typical
chip is less than ¼-square inches and can contain millions of electronic components
(transistors). Computers consist of many chips placed on electronic boards called printed circuit
boards. There are different types of chips. For example, CPU chips (also called microprocessors)
contain an entire processing unit, whereas memory chips contain blank memory.
Semiconductor is a material that is neither a good conductor of electricity (like copper) nor a
good insulator (like rubber). The most common semiconductor materials are silicon and
germanium. These materials are then doped to create an excess or lack of electrons. Computer
chips, both for CPU and memory, are composed of semiconductor materials. Semiconductors
make it possible to miniaturize electronic components, such as transistors. Not only does
miniaturization mean that the components take up less space, it also means that they are faster
and require less energy.
Instead of punched cards and printouts, users interacted with third generation computers
through keyboards and monitors and interfaced with an operating system, which allowed the
device to run many different applications at one time with a central program that monitored
the memory. Computers for the first time became accessible to a mass audience because they
were smaller and cheaper than their predecessors.
Fourth Generation - 1971-Present: Microprocessors
The microprocessor brought the fourth generation of computers, as thousands of integrated
circuits were built onto a single silicon chip. A silicon chip that contains a CPU. In the world of
personal computers, the terms microprocessor and CPU are used interchangeably. At the heart
of all personal computers and most workstations sits a microprocessor. Microprocessors also
control the logic of almost all digital devices, from clock radios to fuel-injection systems for
automobiles.
Three basic characteristics differentiate microprocessors:

Instruction Set: The set of instructions that the microprocessor can execute.

Bandwidth: The number of bits processed in a single instruction.

Clock Speed: Given in megahertz (MHz), the clock speed determines how many
instructions per second the processor can execute.
In both cases, the higher the value, the more powerful the CPU. For example, a 32-bit
microprocessor that runs at 50MHz is more powerful than a 16-bitmicroprocessor that runs at
25MHz. What in the first generation filled an entire room could now fit in the palm of the hand.
The Intel 4004chip, developed in 1971, located all the components of the computer - from the
central processing unit and memory to input/output controls - on a single chip. Abbreviation of
central processing unit, and pronounced as separate letters. The CPU is the brains of the
computer. Sometimes referred to simply as the processor or central processor, the CPU is
where most calculations take place. In terms of computing power, the CPU is the most
important element of a computer system. On large machines, CPUs require one or more
printed circuit boards. On personal computers and small workstations, the CPU is housed in a
single chip called a microprocessor.
Two typical components of a CPU are:

The arithmetic logic unit (ALU), which performs arithmetic and logical operations.

The control unit, which extracts instructions from memory and decodes and executes
them, calling on the ALU when necessary.
In 1981 IBM introduced its first computer for the home user, and in 1984 Apple introduced the
Macintosh. Microprocessors also moved out of the realm of desktop computers and into many
areas of life as more and more everyday products began to use microprocessors.
As these small computers became more powerful, they could be linked together to form
networks, which eventually led to the development of the Internet. Fourth generation
computers also saw the development of GUIs, the mouse and handheld devices
Fifth Generation - Present and Beyond: Artificial Intelligence
Fifth generation computing devices, based on artificial intelligence, are still in development,
though there are some applications, such as voice recognition, that are being used today.
Artificial Intelligence is the branch of computer science concerned with making computers
behave like humans. The term was coined in 1956 by John McCarthy at the Massachusetts
Institute of Technology. Artificial intelligence includes:

Games Playing: programming computers to play games such as chess and checkers

Expert Systems: programming computers to make decisions in real-life situations (for
example, some expert systems help doctors diagnose diseases based on symptoms)

Natural Language: programming computers to understand natural human languages

Neural Networks: Systems that simulate intelligence by attempting to reproduce the
types of physical connections that occur in animal brains

Robotics: programming computers to see and hear and react to other sensory stimuli
Currently, no computers exhibit full artificial intelligence (that is, are able to simulate human
behavior). The greatest advances have occurred in the field of games playing. The best
computer chess programs are now capable of beating humans. In May, 1997, an IBM super-
computer called Deep Blue defeated world chess champion Gary Kasparov in a chess match.In
the area of robotics, computers are now widely used in assembly plants, but they are capable
only of very limited tasks. Robots have great difficulty identifying objects based on appearance
or feel, and they still move and handle objects clumsily.
Natural-language processing offers the greatest potential rewards because it would allow
people to interact with computers without needing any specialized knowledge. You could
simply walk up to a computer and talk to it. Unfortunately, programming computers to
understand natural languages has proved to be more difficult than originally thought. Some
rudimentary translation systems that translate from one human language to another are in
existence, but they are not nearly as good as human translators. There are also voice
recognition systems that can convert spoken sounds into written words, but they do not
understand what they are writing; they simply take dictation. Even these systems are quite
limited – you must speak slowly and distinctly.
In the early 1980s, expert systems were believed to represent the future of artificial intelligence
and of computers in general. To date, however, they have not lived up to expectations. Many
expert systems help human experts in such fields as medicine and engineering, but they are
very expensive to produce and are helpful only in special situations. Today, the hottest area of
artificial intelligence is neural networks, which are proving successful in a number of disciplines
such as voice recognition and natural-language processing. There are several programming
languages that are known as AI languages because they are used almost exclusively for AI
applications. The two most common are LISP and Prolog.
COMPUTER ORGANISATION
It will describe the structure and how different parts of a computer are organised and
how various operations are performed between different parts to do a specific task. As you
know from the previous lesson the internal architecture of computer may differ from system to
system, but the basic organisation remains the same for all computer systems.
 Briefly explain the Basic Computer Operations.
BASIC COMPUTER OPERATIONS
A computer as shown in Fig. 1 performs basically five major operations or functions irrespective
of their size and make. These are 1) it accepts data or instructions by way of input, 2) it stores
data, 3) it can process data as required by the user, 4) it gives results in the form of output, and
5) it controls all operations inside a computer. We discuss below each of these operations.
1. Input: This is the process of entering data and programs in to the computer system. You
should know that computer is an electronic machine like any other machine which takes as
inputs raw data and performs some processing giving out processed data. Therefore, the input
unit takes data from us to the computer in an organized manner for processing.
Fig. 1 Basic computer Operations
2. Storage: The process of saving data and instructions permanently is known as storage. Data
has to be fed into the system before the actual processing starts. It is because the processing
speed of Central Processing Unit (CPU) is so fast that the data has to be provided to CPU with
the same speed. Therefore the data is first stored in the storage unit for faster access and
processing. This storage unit or the primary storage of the computer system is designed to do
the above functionality. It provides space for storing data and instructions.
The storage unit performs the following major functions:


All data and instructions are stored here before and after processing.
Intermediate results of processing are also stored here.
3. Processing: The task of performing operations like arithmetic and logical operations is called
processing. The Central Processing Unit (CPU) takes data and instructions from the storage unit
and makes all sorts of calculations based on the instructions given and the type of data
provided. It is then sent back to the storage unit.
4. Output: This is the process of producing results from the data for getting useful information.
Similarly the output produced by the computer after processing must also be kept somewhere
inside the computer before being given to you in human readable form. Again the output is also
stored inside the computer for further processing.
5. Control: The manner how instructions are executed and the above operations are
performed. Controlling of all operations like input, processing and output are performed by
control unit. It takes care of step by step processing of all operations in side the computer.
 Briefly explain the Functional Units in the computer.
FUNCTIONAL UNITS
In order to carry out the operations mentioned in the previous section the computer allocates
the task between its various functional units. The computer system is divided into three
separate units for its operation. They are 1) arithmetic logical unit, 2) control unit, and 3)
central processing unit.
Arithmetic Logical Unit (ALU)
After you enter data through the input device it is stored in the primary storage unit. The actual
processing of the data and instruction are performed by Arithmetic Logical Unit. The major
operations performed by the ALU are addition, subtraction, multiplication, division, logic and
comparison. Data is transferred to ALU from storage unit when required. After processing the
output is returned back to storage unit for further processing or getting stored.
Control Unit (CU)
The next component of computer is the Control Unit, which acts like the supervisor seeing that
things are done in proper fashion. The control unit determines the sequence in which computer
programs and instructions are executed. Things like processing of programs stored in the main
memory, interpretation of the instructions and issuing of signals for other units of the computer
to execute them. It also acts as a switch board operator when several users access the
computer simultaneously. Thereby it coordinates the activities of computer’s peripheral
equipment as they perform the input and output. Therefore it is the manager of all operations
mentioned in the previous section.
Central Processing Unit (CPU)
The ALU and the CU of a computer system are jointly known as the central processing unit. You
may call CPU as the brain of any computer system. It is just like brain that takes all major
decisions, makes all sorts of calculations and directs different parts of the computer functions
by activating and controlling the operations.
SOFTWARE
HARDWARE
Fig. 2.2: Computer Architecture
Personal Computer Configuration
Now let us identify the physical components that make the computer work. These are
1. Central Processing Unit (CPU)
2. Computer Memory (RAM and ROM)
3. Data bus
4. Ports
5. Motherboard
6. Hard disk
7. Output Devices
8. Input Devices
All these components are inter-connected for the personal computer to work.
Part- C
 Explain the types of storage and memory system in computer
TYPES OF STORAGE DEVICES/ MEMORY SYSTEM IN A COMPUTER
There are two kinds of computer memory: primary and secondary. Primary memory is
accessible directly by the processing unit. RAM is an example of primary memory. As soon as
the computer is switched off the contents of the primary memory is lost. You can store and
retrieve data much faster with primary memory compared to secondary memory. Secondary
memory such as floppy disks, magnetic disk, etc., is located outside the computer. Primary
memory is more expensive than secondary memory. Because of this the size of primary
memory is less than that of secondary memory. We will discuss about secondary memory later
on.
Computer memory is used to store two things: i) instructions to execute a program and
ii) data. When the computer is doing any job, the data that have to be processed are stored in
the primary memory. This data may come from an input device like keyboard or from a
secondary storage device like a floppy disk.
As program or the set of instructions is kept in primary memory, the computer is able to
follow instantly the set of instructions. For example, when you book ticket from railway
reservation counter, the computer has to follow the same steps: take the request, check the
availability of seats, calculate fare, and wait for money to be paid, store the reservation and get
the ticket printed out. The programme containing these steps is kept in memory of the
computer and is followed for each request.
But inside the computer, the steps followed are quite different from what we see on the
monitor or screen. In computer’s memory both programs and data are stored in the binary
form. You have already been introduced with decimal number system, that is the numbers 1 to
9 and 0. The binary system has only two values 0 and 1. These are called bits. As human beings
we all understand decimal system but the computer can only understand binary system. It is
because a large number of integrated circuits inside the computer can be considered as
switches, which can be made ON, or OFF. If a switch is ON it is considered 1 and if it is OFF it is
0. A number of switches in different states will give you a message like this: 110101....10. So the
computer takes input in the form of 0 and 1 and gives output in the form 0 and 1 only. Is it not
absurd if the computer gives outputs as 0’s & 1’s only? But you do not have to worry about.
Every number in binary system can be converted to decimal system and vice versa; for example,
1010 meaning decimal 10. Therefore it is the computer that takes information or data in
decimal form from you, convert it in to binary form, process it producing output in binary form
and again convert the output to decimal form.
The primary memory as you know in the computer is in the form of IC’s (Integrated
Circuits). These circuits are called Random Access Memory (RAM). Each of RAM’s locations
stores one byte of information. (One byte is equal to 8 bits). A bit is an acronym for binary digit,
which stands for one binary piece of information. This can be either 0 or 1. You will know more
about RAM later. The Primary or internal storage section is made up of several small storage
locations (ICs) called cells. Each of these cells can store a fixed number of bits called word
length.
Each cell has a unique number assigned to it called the address of the cell and it is used to
identify the cells. The address starts at 0 and goes up to (N-1). You should know that the
memory is like a large cabinet containing as many drawers as there are addresses on memory.
Each drawer contains a word and the address is written on outside of the drawer.
Capacity of Primary Memory
You know that each cell of memory contains one character or 1 byte of data. So the capacity is
= 32,768 bytes. (1 kilobyte is 1024 bytes). A memory size ranges from few kilobytes in small
systems to several thousand kilobytes in large mainframe and super computer. In your personal
computer you will find memory capacity in the range of 64 KB, 4 MB, 8 MB and even 16 MB
(MB = Million bytes).
The following terms related to memory of a computer are discussed below:
1. Random Access Memory (RAM): The primary storage is referred to as random access
memory (RAM) because it is possible to randomly select and use any location of the
memory directly store and retrieve data. It takes same time to any address of the
memory as the first address. It is also called read/write memory. The storage of data
and instructions inside the primary storage is temporary. It disappears from RAM as
soon as the power to the computer is switched off. The memories, which loose their
content on failure of power supply, are known as volatile memories .So now we can say
that RAM is volatile memory.
2. Read Only Memory (ROM): There is another memory in computer, which is called Read
Only Memory (ROM). Again it is the ICs inside the PC that form the ROM. The storage of
program and data in the ROM is permanent. The ROM stores some standard processing
programs supplied by the manufacturers to operate the personal computer. The ROM
can only be read by the CPU but it cannot be changed. The basic input/output program
is stored in the ROM that examines and initializes various equipment attached to the PC
when the switch is made ON. The memories, which do not loose their content on failure
of power supply, are known as non-volatile memories. ROM is non-volatile memory.
3. PROM There is another type of primary memory in computer, which is called
Programmable Read Only Memory (PROM). You know that it is not possible to modify or
erase programs stored in ROM, but it is possible for you to store your program in PROM
chip. Once the programmes are written it cannot be changed and remain intact even if
power is switched off. Therefore programs or instructions written in PROM or ROM
cannot be erased or changed.
4. EPROM: This stands for Erasable Programmable Read Only Memory, which over come
the problem of PROM & ROM. EPROM chip can be programmed time and again by
erasing the information stored earlier in it. Information stored in EPROM exposing the
chip for some time ultraviolet light and it erases chip is reprogrammed using a special
programming facility. When the EPROM is in use information can only be read.
5. Cache Memory: The speed of CPU is extremely high compared to the access time of
main memory. Therefore the performance of CPU decreases due to the slow speed of
main memory. To decrease the mismatch in operating speed, a small memory chip is
attached between CPU and Main memory whose access time is very close to the
processing speed of CPU. It is called CACHE memory. CACHE memories are accessed
much faster than conventional RAM. It is used to store programs or data currently being
executed or temporary data frequently used by the CPU. So each memory makes main
memory to be faster and larger than it really is. It is also very expensive to have bigger
size of cache memory and its size is normally kept small.
6. Registers: The CPU processes data and instructions with high speed, there is also
movement of data between various units of computer. It is necessary to transfer the
processed data with high speed. So the computer uses a number of special memory
units called registers. They are not part of the main memory but they store data or
information temporarily and pass it on as directed by the control unit.
 Explain the Secondary Storage Devices
2.6 SECONDARY STORAGE
You are now clear that the operating speed of primary memory or main memory should be as
fast as possible to cope up with the CPU speed. These high-speed storage devices are very
expensive and hence the cost per bit of storage is also very high. Again the storage capacity of
the main memory is also very limited. Often it is necessary to store hundreds of millions of
bytes of data for the CPU to process. Therefore additional memory is required in all the
computer systems. This memory is called auxiliary memory or secondary storage.
In this type of memory the cost per bit of storage is low. However, the operating speed is
slower than that of the primary storage. Huge volume of data are stored here on permanent
basis and transferred to the primary storage as and when required. Most widely used
secondary storage devices are magnetic tapes and magnetic disk.
1. Magnetic Tape: Magnetic tapes are used for large computers like mainframe computers
where large volume of data is stored for a longer time. In PC also you can use tapes in
the form of cassettes. The cost of storing data in tapes is inexpensive. Tapes consist of
magnetic materials that store data permanently. It can be 12.5 mm to 25 mm wide
plastic film-type and 500 meter to 1200 meter long which is coated with magnetic
material. The deck is connected to the central processor and information is fed into or
read from the tape through the processor. It similar to cassette tape recorder.
Fig. 2.3 Magnetic Tape
Advantages of Magnetic Tape:




Compact: A 10-inch diameter reel of tape is 2400 feet long and is able to hold 800, 1600
or 6250 characters in each inch of its length. The maximum capacity of such tape is 180
million characters. Thus data are stored much more compactly on tape.
Economical: The cost of storing characters is very less as compared to other storage
devices.
Fast: Copying of data is easier and fast.
Long term Storage and Re-usability: Magnetic tapes can be used for long term storage
and a tape can be used repeatedly with out loss of data.
2. Magnetic Disk: You might have seen the gramophone record, which is circular like a disk
and coated with magnetic material. Magnetic disks used in computer are made on the
same principle. It rotates with very high speed inside the computer drive. Data is stored
on both the surface of the disk. Magnetic disks are most popular for direct access
storage device. Each disk consists of a number of invisible concentric circles called
tracks. Information is recorded on tracks of a disk surface in the form of tiny magnetic
spots. The presence of a magnetic spot represents one bit and its absence represents
zero bit. The information stored in a disk can be read many times without affecting the
stored data. So the reading operation is non-destructive. But if you want to write a new
data, then the existing data is erased from the disk and new data is recorded.
3. Floppy Disk: It is similar to magnetic disk discussed above. They are 5.25 inch or 3.5 inch
in diameter. They come in single or double density and recorded on one or both surface
of the diskette. The capacity of a 5.25-inch floppy is 1.2 mega bytes whereas for 3.5 inch
floppy it is 1.44 mega bytes. It is cheaper than any other storage devices and is portable.
The floppy is a low cost device particularly suitable for personal computer system.
Fig. 2.5 Floppy Disk
4. Optical Disk:
With every new application and software there is greater demand for memory capacity. It is the
necessity to store large volume of data that has led to the development of optical disk storage
medium. Optical disks can be divided into the following categories:
1. Compact Disk/ Read Only Memory (CD-ROM): CD-ROM disks are made of reflective
metals. CD-ROM is written during the process of manufacturing by high power laser
beam. Here the storage density is very high, storage cost is very low and access time is
relatively fast. Each disk is approximately 4 1/2 inches in diameter and can hold over 600
MB of data. As the CD-ROM can be read only we cannot write or make changes into the
data contained in it.
2. Write Once, Read Many (WORM): The inconvenience that we can not write any thing in
to a CD-ROM is avoided in WORM. A WORM allows the user to write data permanently
on to the disk. Once the data is written it can never be erased without physically
damaging the disk. Here data can be recorded from keyboard, video scanner, OCR
equipment and other devices. The advantage of WORM is that it can store vast amount
of data amounting to gigabytes (109 bytes). Any document in a WORM can be accessed
very fast, say less than 30 seconds.
3. Erasable Optical Disk: These are optical disks where data can be written, erased and rewritten. This also applies a laser beam to write and re-write the data. These disks may
be used as alternatives to traditional disks. Erasable optical disks are based on a
technology known as magnetic optical (MO). To write a data bit on to the erasable
optical disk the MO drive's laser beam heats a tiny, precisely defined point on the disk's
surface and magnetises it.
 Explain about input and output devices
INPUT /OUTPUT DEVICES
A computer is only useful when it is able to communicate with the external
environment. When you work with the computer you feed your data and instructions
through some devices to the computer. These devices are called Input devices. Similarly
computer after processing gives output through other devices called output devices.
For a particular application one form of device is more desirable compared to others.
We will discuss various types of I/O devices that are used for different types of
applications. They are also known as peripheral devices because they surround the CPU
and make a communication between computer and the outer world.
Input Devices:
The term input device is used to describe the process of capturing or collecting raw data, at the
beginning of a computer based information system into a form that is usable by the computer for
processing.
The following are belongs to the input devices
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
Keyboard
Mouse
Touch screen terminals
Optical mark readers
Barcode readers
Scanner
MICR
Smart cards
Voice input devices
Pointing devices (Light pen)
1. Key board:

It allows us to interact with the computer. It is used to send information / data and commands
to the computer. It is similar to the keyboard of typewriter.

It is a sophisticated electromechanical component designed to create special standardized
electronic codes when a key is pressed.

It is the most commonly used interface between the user and the computer.

The codes are transmitted along the cable that connects the keyboard to the computer system
or terminal, where the incoming code is analyzed and converted into the appropriate computer
usable code.
It can be divided into following
a. Standard typewriter key area
b. Function keys
c. Special purpose keys
d. Cursor control keys
e. Numeric keys
a. Standard typewriter keys:
These are the keys normally function similarly to the keys found on a typewriter. These are used
to type in text and other data. These include the keys like letters, numbers and punctuation symbols
etc.
b. Function keys:
These are normally has 10-12 keys. These keys labeled F1 to F12. These keys allow giving
frequently used commands to the computer without typing long words and sentences. This will perform
specific tasks as defined by the particular software program currently running on the computer system.
These also called as programmable keys.
c. Special Purpose Keys:
These keys have some specific function or tasks to perform. These are enter, backspace, Del
(Delete), INS (Insert), Ctrl (Control) and Alt (Alternate).
Ex. Shift keys are used to alter the default cases of letters or type the top character present in the key.
(Either upper or lower case).
d. Cursor control Keys:
These are used to control the movement of cursor. These are used to move the cursor around
the screen. They have directional arrows in them. When one of the key is pressed the cursor will move
in the direction of the arrow indicated on the keys. Individual software application will have specifically
defined instruction for the use of cursor control keyboard.
e. Numerical Keys:
On the right hand side of the keyboard is the numeric key. These are used to enter numeric for
mathematical manipulation. Some of the keys having double functions. The switch over between the
two functions of a key is controlled by the key marked Numlock.
2. Mouse:

It is hand held device that controls the movement of the cursor or pointer on a display screen.

It is a small object you can roll along a hard, flat surface. Its name is derived from its shape,
which looks a bit like a mouse; it is connected to the computer by a small cable that one can
imagine to be the mouse tail.

It was invented by Douglas Engelbert of Stand ford Research center in 1963. It is the one of the
great breakthrough in computer ergonomic because it frees the user to a large extent from
using the keyboard.

Mouse contain at least one button and sometimes as many as three, which have different
functions depending on what program is running.

This is important for graphical user interface because you can simply point to the options and
objects, and click a mouse button. Ex. It can be used as a pen or paint brush to create figures or
patterns directly on the video display unit.
Types of Mouse
There are 3 basic types
1. Mechanical
2. Optical
3. Optomechanical
1. Mechanical – Has a rubber or metal ball on its underside that can roll in all direction.
Mechanical sensor within the mouse detects the direction. Mechanical sensors within the
mouse detect the direction the ball is rolling and move the screen pointer accordingly.
2. Optomechanical – Same as mechanical mouse, but uses optical sensors to detect motion of the
ball.
3. Optical –Uses a laser to detect the mouse movement. You must move the mouse along with a
special mat with a gird so that optical mechanism has a frame of reference. Optical mice have no
mechanical moving parts. They respond more quickly and precisely than mechanical and opto
mechanical mice, but they are also more expensive.
Mouse Pad: It is a pad, over which you can move a mouse this provide more traction than
smooth surface such as glass and wood, so they make it easier to move a mouse accurately. For
mechanical mice it is optional. Optical mouse require special mouse pad that have grids drawn
on them.
3. Touch Screen Terminals:
It is a type of display screen that has a touch sensitive transparent panel covering the screen.
Instead using a pointing device such as a mouse or light pen, you can use your finger to point directly to
objects on the screen. Limited amounts of data can be entered through a micro computer that has a
touch screen. The software determines the kinds of choices the user has.
4. Barcode Reader:
You are probably familiar with the barcode readers in supermarkets, bookshops etc. These are
photoelectric scanners that read the barcodes or vertical zebra striped marks printed on product
containers by the manufacturers and usually carry the inventory stock number. The coding scheme
called as Universal Product Code (UPC) for recording the data is based on the width of the bars and
space between them. This has a description and the latest price of the product. The computer
automatically tells the (point of sale) PoS terminal what the price is.
5. Optical Mark Recognition: (OMR)
In this method special pre-printed form are designed with boxes which can be marked with a
dark pencil or ink. Each box is annotated distinctly so that the user clearly understands what response
he is marking. Ex. In some examinations, the answers are marked on a preprinted sheet using a lead
pencil; this is the simplest form of optical data recording optical works.
The OMR device has a high intensity light inside, that is directed in the form of a beam at the
sheets of paper being fed through it. The beam scans the marked forms and detects the numbers and
location of the pencil marks. Then the data is converted into electrical signals for the computer. They are
used for
1. Objective type answer papers in examination in which large no of candidates appear.
2. Market surveys, population surveys
3. Order forms containing a small choice of items
4. Time sheets of factory employees in which start and stop times may be marked.
6. Scanner:
It is an input device that can read text or image of a photograph or illustrations printed on paper
and transfer the information into a form that the computer can use. A scanner works by digitizing an
image dividing into a grid of boxes and representing each box with either a zero or one, depending on
whether the box is filled in. these can be stored in a file, displayed on screen and manipulated by
programs. It is like a photocopy machine. It consists of a board on which you lay books, magazines and
others documents that you want to scan.
7. Magnetic Ink Character Recognition (MICR):
This allows the computer to recognize the character printed using magnetic ink. MICR is a directentry method used in banks such as cheques. The special symbols printed on cheques are read
electronically by a special purpose machine known as a reader sorter (MICR). The data is stored on tape
or disk for processing the cheque is then sorted by bank numbers and returned to the bank.
8. Smart Cards:
These are designed to be carried like tiny transaction computers. To use it, the card holder
inserts the card in to a special card reading point of sale terminal and than enters a password on to
keyboard. These having microchips that can keep permanent records which are updated each time the
card is used. Ex. ATM cards, Debit cards, Credit cards etc.
9. Voice Input Devices:
In an effort to increase the worker productivity a substantial amount of research is being doe in
voice or speech recognition programming the computer to recognize spoken commands. This device or
voice recognition systems convert the spoken words into electrical signals by comparing the electrical
patterns produced by the speaker’s voice with set of pre-recorded patterns.
IBM voice type identifier more than 30,000 words and adapts to individual voices. These are even
systems that will translate from one language to another, such as English to Japanese.
10. Pointing Device (Light Pen):
Data input also involves entering commands and selecting options. This device allows the user
to identify and select the necessary command or option by moving the cursor to a certain location on
the screen or sending a signal to the computer. It uses a light sensitive photoelectric cell to signal screen
position to the computer, there by indicating x-y screen co-ordinates to the computer. Or it utilizes a
light sensitive detector to select objects on a display screen. It is similar to mouse except it is directly
pointing the objects with the pen on the display screen.
They are frequently used by graphics designers, illustrators and drafting engineers.
 Explain the output devices.
OUTPUT DEVICES
There are three principal devices to get output information from a computer. They are Printers,
Video terminal and Computer output microfilm. Under this three printing is the most common method.
Microfilm is expensive and used only for special purposes. Printing and microfilming units are called as
hard copy devices as the data written using these devices can be read by people. There is another set of
output devices called as soft copy devices, which store data as bit strings. They can be read and
interpreted only by computer.
Printers:
It is capable of printing characters, symbols, and sometimes graphics on paper. Printers are
categorized according to whether or not the image produced is informed by physical contact of the
print mechanism with the paper.
1. Impact printers
2. Non.- impact printers
Impact printers
It is usually forms the print image by pressing as inked ribbon against the paper with a hammer
like mechanism and makes contact with the paper. They are Letter quality printers, Dot matrix
printers, and High speed printers.
1. Letter Quality Printers - These also called as serial printers or character printers. Because they
print one character at a time, produce a very high quality print image because the entire
character is formed with a single impact. These are similar to type writers. This will produce 30300 char/sec
The main advantage is excellent image produced.
Disadvantage

They are slow for large volume output situations

They are noisy

To change the type of face style, the operator must halt machine and change the print wheel.

They cannot produce graphics.
2. Dot Matrix printers – These are developed with two objectives
1. Greater speed (50-500 Char/sec)
2. More flexibility
It creates characters by striking pins against an ink ribbon. Each pin makes a dot and combinations of
data from characters and illustrations. The print head consist of series of print hammers that looks like
the head of pins. These are bidirectional i.e. print from left to right as well as print from right to left on
return. This feature the speed up printing. They are a variety of type styles and graphics without
requiring an operator to stop the printer or change the print wheel. They generate less noise than letter
quality printers. They can print multi page forms (i.e. carbon copy) something laser and inkjet printer
cannot do.
3. High Speed Printers – These are non serial printers have been developed to satisfy the high volume
output requirements of most large computer installations. These are referred as line printers, because
they print whole line at a time. They can print as many as 3,000 lines per minute. Ex. Drum printers,
band or belt printers.
Disadvantage

These are print only one font, they cannot print graphics

Print quality is low

They are noisy
Non-Impact Printers:
These are do not strike characters against ribbon or paper. These generate much less noise than
impact printers. These are Inkjet printers, Laser printers, Thermal printers etc.
1. Ink-Jet Printers - This printers work in much the same fashion as dot matrix printers. They form
characters with little dots. However in that dots are formed not by hammer like pins but by spraying
ionized ink at a sheet of paper. An inkjet printer consists of a print head which has a number of small
holes or nozzles. Individual holes can be heated very rapidly (in a few microseconds) by an integrated
circuits resistor. When the resistor heats up the ink near it vaporizes and is ejected trough the nozzle
and makes a dot on the paper placed near the head. A high resolution inkjet printer has around 50
nozzles within a height of 0.276inch and can print with resolution of 300 dots per inch. The head is also
moved rapidly across the paper. It has multiple heads, one per color which allows color printing. The
printing speed is around 120 char/sec.
Disadvantage

They are slower in speed

These are expensive way to print full color documents.

The cost of inkjet cartridge is high and thus cost per page of printing is quite high about 10 times
of dot matrix printing.
2. Laser Printers – The dot matrix, line printers and other printer has mechanical movements that sloe
down the printing speed. Intensive research and development with the goal to eliminate mechanical
motion in printers led to the development of laser printers. In this printer the electronically controlled
laser beam traces the desired character to be printed on a photoconductive drum. The drum attracts the
tuner on the exposed areas. This image is transferred to the paper which comes in contact with the
drum by a combination of heat & pressure. This is also the way of copy machine works. They also called
as “page printers”. The speed ranges from 4-20 pages of text per minute.

They are relatively very fast,

Low noise level

Excellent graphic capabilities

Very high image quality

A variety of type sizes and styles

They are very expensive

Low maintenance
Visual Display Unit
The most popular input/output device is the Visual Display Unit (VDU). It is also called
the monitor. A Keyboard is used to input data and Monitor is used to display the input data and
to receive massages from the computer. A monitor has its own box which is separated from the
main computer system and is connected to the computer by cable. In some systems it is
compact with the system unit. It can be color or monochrome.
Different Types of Monitors
There are many types of computer monitors which are below
CRT Monitors
Some computer monitors generate output with the help of cathode ray tubes. This type of device is
called the CRT (or, cathode ray tube) monitor. Some computer users prefer this style because it offers a
richly colored display and does not break easily. However, CRT monitors can be bulky and take up a lot
of desk space, very heavy to carry, and they require a lot of power to run properly. Moreover, the
picture screen can distort, display a "flicker effect," or burn out over time.
Flat screen CRT Monitors
Basically a CRT monitor with a better picture and a slimmer space-saving form factor. Colors and
sharpness may be improved from the basic CRT depending on the resolution of the monitor.
LCD Monitors
Liquid crystal display (LCD) monitor is the latest development in monitor technology. LCD and plasma
screen styles are relatively thinner and much lighter than their older CRT counterparts. They display
sharp, excellent images and require less power to run, thus let you save money in energy costs.
However, these newer models can be more expensive than traditional computer monitors. LCD screens
have been used in laptops for a while but have only recently become popular as desktop monitors.
Plotters
A plotter is a specialized output device designed to produce high quality graphics in a variety of
colours. There are two basic types of plotters, those that use pens and those do not. Drum plotters and
flat bed plotters both use pens, electrostatic plotters do not.
Drum Plotters- in a drum plotter, the paper is mounted on the surface of a drum. The drum revolves
and the plotter pens are horizontally positioned over the target area. When the paper has rotated to the
correct point, the pens are dropped to the surface and moved left and right under progress control
across the paper as the drum revolves. When the pens are raise from the surface.
Flatbed Plotters- these are designed so that the paper is placed that and one or more pens more
horizontally and vertically across the paper.
Electrostatic Plotters- these are electrostatic charges to create images out of very small dots on
specially treated paper. The paper is run through a developer to allow the image to appear. These are
faster than pen plotters and can produce images of very high resolution.
NEHRU ARTS AND SCIENCE COLLEGE
THIRUMALAYAMPALAYAM -COIMBATORE
DEPARTMENT OF COSTUME DESIGN AND FASHION
STUDY MATERIAL
COURSE
: III-B.SC (CDF)
SEMESTER
: V
SUBJECT
: COMPUTERS IN GARMENT INDUSTRY
UNIT
: II
LECTURER NAME
: V.S.KARPAGAVALLI
Part – A
1. Product data management (PDM) facilitates communication and accelerates the
co- ordination of the product development cycle.
2. Define CAM. Computer Aided Manufacture.
3. The automatic sewing machines have the automatic bobbin winder/changes.
4. The automatic sewing machines automatically folds, sews and these are easy to
operate and easy to maintain.
5. Define CIM. Computer Integrated manufacture
6. Collar attachment machine helps in attaching the collars to the bodice block.
7. The Uster ring data for ring spinning determines the productivity and quality of
the ring spinning process.
8. Computer Aided Pattern Drafting software enables designers to illustrate and
visualize their designs both 2D and 3D forms.
9. Unit Production System is the advanced version of the hanger system.
10. Steam dolly machine which is a mechanized tailor’s dummy consisting of a
shaped inflatable nylon bag into which steam and air are blown.
Part - B
 Briefly explain the role of Computers in garment Industry.
Role of computers in fashion industry- information flow- CAD, CAM, CIM, CAA, PDC- definition and
functions. Computers in production planning and production scheduling, computerized color matching
system.
Role of Computers in Fashion Industry
Computers play a huge role I the fashion industry and every year its role increases
enormously. Globalisation, speed of information and communication has stimulated
competition. While manufacturers offer unlimited designs, the program is how to bring
products to the market quickly and achieve up to date information that is easily obtainable. The
fashion industry would not be able to function or expand without computers. It would affect
producers, distributors and consumers. In addition to this marketing and sales would go down,
Clothing production, warehousing and shipping would deflate.
With the industry going high tech, a familiarity with computers is a necessity. It has
enabled the clothing design, pattern construction and product development to be integrated in
to a more continuous process. The world of fashion is extremely exciting and fast paces with
technology, trends and models. It includes different industries the designing, manufacturing,
distribution of clothing & accessories, wholesale and retail sales and fashion media, and
photography. They all need computers to function.
Us consumers spend approximately $ 140 billion per year in apparel. US people most of
them uses computers consistently, especially to shop. Computers are important for
presentation and modification of fashion designs. It enables designers to illustrate and visualize
their designs both 2D and 3D forms. It enables the pattern technologist to construct and grade
the pattern simultaneously by using the software like Computer Aided Pattern Drafting.
(CAD/CAM). Ex Arah weave which lets fabric designers experiment with colors, yarns and
weaves while viewing detailed, realistic on screen samples.
An important program is Quick Response which is a business model for compressing
supply chains quickly obtain raw materials such as fabric, yarn, buttons and zippers. It is used to
communicate or interacting with colleagues or customers through e-mail. Product data
management (PDM) which facilitate communication and to accelerates the co- ordination of
the product development cycle. This manage the critical path, which help keep track through
reports on the progress of each product and by identifying potential problems. The computers
are in wearable technology as clothing which contains digital devices. Ex. SCOTTeVEST which is
a man or woman’s jacket with pockets for cell phones. MP3 player, iPods and built in wiring to
connect these devices to a personal area network. This saves time, broaden sales, online
shopping, create online runways, post websites etc.
 Explain on Computer Aided Design
CAD (Computer Aided Design)
It is defined as the design activities including drafting and illustration, in which data
processing systems are used to carry out functions such as designing or improving a part or a
product. CAD program may provide precise dimensioning and positioning of each graphic
element for designing and manufacturing purpose. (Computer based tools to physically design a
product).
The capabilities of CAD includes
1. Reuse of apparel design components
2. Ease of design modification
3. Automatic generation of standard components of the design.
4. It converts his or her ideas and knowledge visualizes final product appearance without
building expensive and time consuming physical prototype.
5. It can produce pattern drawings and marker plans.
6. It can integrate into the apparel manufacturing data processing systems.
It is used as a tool of analysis and design for electronic, mechanical design, construction, and
chemical process industry, medicine and fashion, textile design etc.
 What is a CIM. Briefly Explain.
CAM (Computer Aided Manufacture)
It describes the use of computer technology to aid in the manufacturing process,
handling or transport of goods. It is most widely used in the control of robotic machines which
perform manufacturing tasks too large, too short, and too exacting or the tiresome for human
beings.
Ex. Automatic fabric spreading machines, Automatic cutting machines.
This introduces flexible automation on the shop floor. These are used in the application
aircraft, automobile and general engineering industry.
In this raw materials are physically transferred into finished goods. For ex. In a yarn
production facility fibers are opened, cleaned, carded, and spun into yarn using the appropriate
technology. Coupled with proliferation of automation and robotics, a truly Computer Aided
Manufacturing environment is emerging; it can be grouped in to major categories process
control and materials handling.
Functions

Spreading

Cutting

Sewing

Pressing

Finishing

Dispatch
Spreading:
It is the process of converting the roll form into lay form. The length of lay is decided
upon no of patterns to be placed and width depends upon the fabric. The spreader or travelling
machine which automatically spread the fabric into lay form according to our requirement.
Cutting:
There is a computer controlled cutting machine. Ex. Gerber cutting machine, It has a
head which carries the knife or blade. The cutting table and its carriage and cutting head is able
to move between the spreading tables by means of tracks on the floor. The conveyor with its
bristle surface also assists in cleaning waste material from the surface.
Computerized Sewing:
a. Hanger System - Less handling time involved. This can be changed according to the
requirements. There is no any disturbance to the workers. Heavy ironing is not essential.
Speed of the hanger is moved within the standard pitch time of the workers.
b. Unit Production System – This is the advanced version of the hanger system. In this
component parts are not removed for joining the parts but it is hung on it & the sewing
is done without removing the component part from the UPS. It eliminates bundling
time, reduces handling and 25% of the efficiency can be increased.
 Explain on the Automatic Sewing Machines.
Automatic Sewing Machines:
1.
2.
3.
4.
5.
Pocket setter machine
Collar attachment machine
Bar tacking machine
Cover stitch hammer machine
Button hole machine
These machines have the automatic bobbin winder/changes. The unit automatically
folds, sews and these are easy to operate and easy to maintain. Ex. In buttonhole
machine it has a sensor, when the button is placed on the sensor button hole foot, the
sensor then sets the necessary length and the perfect button hole is automatically made
in one step.
Computer Controlled Pressing:






The need to press garments during and at the end of their production is a basic
requirement in order to shape and finish them.
Steam dolly machine which is a mechanized tailor’s dummy consisting of a shaped
inflatable nylon bag into which steam and air are blown. The garment to e pressed is put
on to form and steam is forced through it. The accidental creases present in the
garment will be removed.
The timing and the type of garment which is to be pressed is fed in the computer.
Generally 8 sec for steaming.
The stretch controller is present to avoid change in dimensions of stretchable materials.
Ironing is also available for pockets & options are also available to hole label collars and
the buttons
Pneumatic tension control is provided to avoid any distortion of the garments.
This is suitable for normal dresses, aprons, jackets, blouses, coats, long garments etc.
Finishing and Dispatch:


The garment for finishing is hung on the hanger with different sizes on styles and more.
It is then passed to automatic handling a sorting section where the garments are sorted.



The sorted garment then moves to tunnel finish where the heat is passes in the form of
steam and creases are removed.
Then it moves to the folding area where the garments are folded and finally dispatch in
the neat form.
This system works on the basis of management information system.
Thus CAM incorporates all area of the industry such as productions, assembly, dispatch,
spares and inventory control etc.
Part - C
 Explain on CIM and its Functions.
COMPUTER INTEGRATED MANUFACTURE (CIM)
It is a concept for the computer supported integration of all technical aspects of
company management, as well as those related to t he operational works management.
It is the complete automation.
The successful application of CIM necessitates the following
 Computer control of all aspects of quality, productivity and machine operation.
 Communication ability with respect to the downloading of production parameters and
the detection of process data.
 Automation with respect to input and output, i.e. either directly integrated with the
previous and the subsequent process stages or as part of a flexible automatic
transportation and handling systems.
The purpose of such a concept is the achievement of optimal condition material
management and process scheduling , this serves for a continuous improvement in
various manufacturing parameters such as lead time, work-loads, just-in-time deliveries,
on-stock parts flexibility, capacity planning and product quality.
Functions of CIM in various fields of textiles:
1.
Spinning:
It is almost completely controlled by computers. The features include.
 Automated material handling with auto storage and retrieval systems that can deal with
raw materials and finished products.

Once the yarn is made, automatic palletizing, conditioning and packing of
yarn can occur.





Work in process tracking equipment can identify the whereabouts of
inventory level
Automatic bale lay down and monitoring of blending lines can ensure optimization of
raw material and better yarn quality.
Auto feeding to card from blending and opening lines can be installed.
At carding, pressuring sensors at chute, monitor and control the feed to card auto
leveling devices at the feed mat can sense the evenness of the material and adjust
accordingly as per set norms
In drawing auto leveling of feed silver based on material weight. Trumpet sensors to
measure the evenness of “delivered” silver.
As online quality and productivity supervising systems for the processes before spinning
is now available, the USTER SLIVER DATA.
The USTER RING DATA for ring spinning which determines the productivity and quality
of the ring spinning process.
2. Weaving:
The use of on-board micro processor on machines bi-directional communication can
occur with computer devices. These provide auto data collection, monitors and controls
the processes. USTER MILL DATA is the integral computer support of all stages of the
production process and it makes possible all organizational measures for adapting the
system to the available mill conditions, e.g. order processing, material flow, costing,
planning etc.
It is a system for production planning and process control (PPS), disposition and order
processing. It makes possible a computer aided planning (CAP), a means of automatic
setting of the machine parameters (CAM) and a method of supervision of product
quality (CAQ). The TWEED system for weave design covers the design functions (CAD)
MILL DATA is the first product of a new generation of data systems for weaving mills. It
includes
the latest software technology.
 UNIX operating system for administration works and data preparation.
 Relational database management system (DBMS) for automatic login, the
handling and complex simultaneously running transactions
 4th generation languages
 Network communication.
Apparel Industry:
Great strides have been made during recent years in automating many of the processes
and machines for the apparel industry. Automatic spreaders for spreading of fabric are
available, as well as computerized marking and pattern grading to optimize fabric
consumption.
Once the fabric is spread, Computer Numerically Controlled (CNC) cutting devices and
tables are available to run from a cost data program. There are also devices that
provides for automatic identification and elimination of defects and optimization of cutout.
These produce less waste than conventional cutting programs Automatic sewing
machines are available to form the fabric into apparel.
CIM uses KBS (Knowledge based systems) for analyzing defects in textile and apparel
manufacturing. Two developed systems one for fabric defects and other for apparel
defects. FDAS is a KBS for analyzing and diagnosing defects in woven textile structures.
This identifies the defect and suggests suitable remedies to avoid defects.
Sewing Defect Analysis Systems (SDAS) is a KBS for the identification and diagnosis of
defects encountered in the manufacture of utility denim trousers.
CIM help to produce the right mix of goods eliminate bottlenecks in manufacturing and
reduce production times. Consequently, the cost of producing the goods can be
reduced. Moreover the organization can be geared to meet market demands and
operate successfully under this philosophy.
 Explain the Functions of Computer Aided Administration.
COMPUTER AIDED ADMINISTRATION (CAA)
Computer based administration is the area with which the clothing industry has the
most experience. (Ex. Accounts, wages, Human resource and logistics etc)
Functions:
1. Personnel:
 Hiring the persons, training given to them with regard to the job, record keeping,
payment to the workers, and the termination of the worker details.
 Describing employment requisitions, job description, training specification, personal
data, pay role changes of working hrs, pay checks, benefits & termination notice.
 Producers for action like training, hiring, and termination changing pay rates etc. are
also programmed and functioned accordingly.
 Finally the available results obtained the company checks for the difference between
the plan & actual performance like no. of employees hired, cost of recruiting,
composition of skilled inventory, cost of training, salary paid, etc. is compared with
profit obtained. The deviation will be analyzed and corrective measure has to be taken.
2. Marketing and Sales:
 The need for a product is identified by the marketing division. The specification of the
product, the projection of manufacturing quantities and the strategy for marketing the
product also decided by the marketing department.
 Transaction process involves the sales order, promotion orders; etc CAA includes
operational control activities like training of sales force, day to scheduling of sales and
promotion efforts, periodic analysis of sales volume by region, product, and customers
etc.
 Comparison of overall performance against a marketing plan, information for
managerial control includes a data on customers, competitions, products, sales force
requirements. Ex using bar chart, pie chart results would be compared.
 This is very helpful in the achievement of the marketing objective. Using the Outlook
express they will communicate with the customers, and get the information of the
product by means thro’ easy network systems of internal, and they will keep track of all
process sequence up to date information though this internal communication (Outlook
express)
3. Order processing:
Modern apparel distribution centers use computerized storage and picking system that
they rely on bar-coding for storage and retrieval of garments when needed to fill orders.
Computer system permits integration of many of the ordering and distribution process.
In Customer order processing (COP) software, orders are entered into the computer
and the COP system produces bar code labels that when scanned can produce packing
slips, bills of loading or invoices. This system can stand alone or can be integrated with
the apparel production and / inventory control systems such s these reduce
administrative costs and assure more accurate delivery or products to the customers.
4. Stock Control:



It involves the activities like purchasing, receiving inventory control and distribution.
This function uses the information contained in reports such as part due purchases, part
due shipments to customers, out of stock items, over stock items, inventory turn over
reports, vendor performance summary and shipper performance analysis.
This includes the overall comparison between planned and actual inventory cost of
purchase items.


Based on the above information, the storage planning is made regarding the new
policies to vendor’s information on new technology.
TIM software ( Textile Integrated Manufacture) is adopted to specific textile work areas
and the use of 32 bit 80836 and 80486 microprocessors which have the capability to run
all application software’s written for 8088/8086/80286, makes it possible to use both
UNIX and MS-DOS operating systems.
Thus CAA works and helps in the achievement of objectives of the management.
 Explain the advantages of Computers in Production Planning and Scheduling.
COMPUTERS IN PRODUCTION PLANNING AND SCHEDULING
Rising energy prices, global competition and shortage of skilled labor is resulting
in greater pressure on process plants. Process industries are looking for ways to remain
profitable, more efficient and meeting regulation of the customer. The use of third
generation process simulation software is one way the industry is improving efficiency
and increasing production while meeting regulation and oversight in these economic
conditions.
To obtain these, have to make third generation simulation a part of every plant
automation project. Just as NASA uses simulation to astronauts can master various
space sceneries. The process industries can use simulation to test automation systems
and train operations offline before they go live on the real process plant, without danger
to the plant or personnel.
By testing this for normal, abnormal and upset conditions, the user can verify
that the application software has been designed and implemented to meet the
functional needs of the process as well as testing requirements of validated industries.
This improves plant safety, environment protection, operation competency, overall
efficiency and production.
PRODUCTION PLANNING:
 It is a long term view basis to the marketing forecast.
 It is the predetermined course of action about whether the production unit can
cope with the expected sales, in terms of overall volume and in terms of
specialized plant i.e. using the available capabilities like machines, training staff,
human resources (labors) to meet the objective of the business organization or
to meet the production target.


Production planning is the most important function which emphasize on the
activities and functions to prepare a detailed set of plans and instructions to
produce (or policies) a part.
This provides more detailed step-by-step work instructions. Actual planning
works starts when a production order, graded patterns and raw materials are
ready to be issued to the factory by the operations dept.
Manufacturers have been purchasing an evolutionary path to improve and
computerized process planning in the following stages.
Stage1 – Manual classification, standardized process
Stage2 – Computer maintained process plans
Stage3 –Variant CAPP
Stage4 – Generative CAPP
Stage5 – Dynamic, generative CAPP
Here we use Computer Aided Process Planning (CAPP) which evolved as
a means to electronically store a process plan once it was created, retrieve it, modify it
for a new part and print the plan. The initial approach of CAPP evolved in to “Variant
CAPP”. It is based on a Group Technology (GT) coding and classification approach to
identify a larger number of part attributes or parameters. There attributes allow the
system to select a base line process plan for the part family and accomplish about 90%
of the planning work. The planner will ad the remaining 10% of the effort modifying or
fine tuning the process plan. The base line process plans stored in computer are
manually entered using a super planner concept, which is, developing standardized
plans based on the accumulated experience and knowledge of multiple planners and
manufacturing engineers.
The next stage of evolution is toward generative CAPP. At this stage,
process planning decision rules are built into the system. These decision rules will
operate based on a part’s group technology or features tech. coding to produce a
process plan that will require minimal manual interaction and modification. This
involves the use of artificial intelligence type capabilities to produce plans as well as fully
integrated in a ‘CIM’ environment. The process plan developed with CAPP system at
stage ‘V’ would vary over time depending on the resources and work load in the factory.
The first key to implement a generative system is the development of
decision rules appropriate for the items to be processed. A second key to generative
process planning is the available data selected to the part to drive the planning.
SCHEDULING:
It is a key concept in computer multitasking and multiprocessing operating
system design, and in real time operating system design. It refers to the way processes
are assigned priorities in a priority queue. This is carried out by software known as
scheduler. It consists of mainly CPU utilization. In real time environment such as mobile
devices are used an administrative back end was the scheduled tasks are sent to mobile
devices for automatic control in industry. The scheduler must ensure that processes can
meet deadlines, this is crucial for keeping the system stable.
Three distinct type of scheduler
1. Long-term scheduler
2. Mid term scheduler
3. Short term schedulers
1.
2.
3.
4.
5.
Long-term Scheduler: Indicates what process to be carried on first and the degree of
concurrency to be supported at any one time.
Mid term Scheduler: Present in all systems with virtual memory. This scheduler may
decide to swap out a process which has been active for sometime or has a low priority
or page faulting frequency or a process which is taking up a large amount of memory in
order to free up main memory for other processes swapping the process back when
memory is available.
Short term Scheduler: Which of the ready in memory process are to executed. This
makes scheduling decisions much more frequently than long term or mid term
schedulers. Here the Windows-NT based operating systems are used.
There is various software programs are available for production planning and
scheduling which are below.
Computer Aided Production Management (CAPM)
Manufacturing Scheduling & Production Planning
Real time Manufacturing Planning Software
Capacity Planning Software
Manufacturing Resource Planning (MRP) & Enterprise Resource Planning (ERP)
Lean Manufacturing Software.
1. Manufacturing Scheduling & Production Planning:
This is the fastest software for production scheduling in the market. It will
maintain high customer service levels while in terms of order fulfillment and stocking
levels while ensuring that manufacturing efficiency is not compromised. It is highly
complex manufacturing operations which may process thousands of products in an
environment where minimizing changeover and balancing resource usage are vital.
2. Real time Manufacturing & Scheduling:
It provides strategic and tactical level planning capabilities. It is fast enough to
schedule complex operations in real time. It has the ability to automatically reschedule
very large operations in a matter of seconds enables it to respond dynamically for
operational issues while maximizing the efficiency of the production process.
3. Capacity Planning Software:
It will process the manufacturing operation over extended timescales. It takes
actual or forecast orders as input and automatically generates production planning &
schedules and inventory requirements based on production capacity. It provides
powerful graphical user interface which displays the schedule in the form of Gantt
charts, histograms or tabular reports depending on the preference of the user. It
enables the user to quickly asses the schedule and identify potential opportunities or
issues.
4. MRP & ERP:
It will help to increase the productivity in manufacturing and improve profits and
market share applications. These are used to organize and manage the manufacturing
environment. It can interface with corporate database to receive or send live
information about production plans and manufacturing schedules in-real-time. It is
often used in conjunction with or e-stock (inventory control) and I Data (demand
forecasting) modular. These are taken as input and automatically generating production
schedules or plans which in turn can be automatically transmitted to process control
systems.
5. Lean Manufacturing Software:
It is a state of the art computer aided manufacturing software solution which can
help your business in its drive towards lean manufacturing. It provides optimization in
seconds and in addition to day-to –day scheduling activities. It is user friendly by
providing graphical tools for data entry, manual scheduling and reporting alongside its
powerful optimization.
The above all software provides optima ton of the production process, and resource
management. The powerful scheduling reduces wastages in the manufacturing process
and process and improves customer service levels while simultaneously increasing
efficiency and maximizing output.
NEHRU ARTS AND SCIENCE COLLEGE
THIRUMALAYAMPALAYAM -COIMBATORE
DEPARTMENT OF COSTUME DESIGN AND FASHION
STUDY MATERIAL
COURSE
: I II-B.SC (CDF)
SEMESTER
: V
SUBJECT
: COMPUTERS IN GARMENT INDUSTRY
UNIT
: III
LECTURER NAME
: V.S.KARPAGAVALLI
Part - A
1. CAD helps the designers to visualize and see their imaginative design in final
form without producing any sample swatch
2. Textile designing comprises of weaving, knitting and printing.
3. Illustrations/ Sketch Pad Systems are graphic programmes that allow the
designer to use pen or stylus on electronic pad or tablet thereby creating
freehand images.
4. Design Desk handles weaves, yarns, patterns and construction parameters to
instantly simulate realistic fabric on screen.
5. Auto weave insertion facility is responsible for integrating dobby effects directly
onto a design in ornamentation or extra warp mode.
6. Design Desk allows you the liberty of choosing the apt set of color ways for a
design under development.
7. Simulation is enhanced by using yarns created or scanned directly into the
library.
8. Computer Aided Design (CAD) and Computer-Aided Manufacturing (CAM) have
revolutionized the knitting industry.
9. Define draft? Peg plan done numerically or directly drawing on point paper.
Part- B
 Explain the role of CAD in Designing.
CAD in Designing
Textile designing – weaving, knitting and printing. Creating embroidery designs. Garment
designing – 2D and 3D forms.
CAD in designing
CAD or Computer-aided design
has brought a revolution in the Textile Industry. The time consuming and cumbersome process
of textile designing has been made easier by CAD. Now thoughtful and innovative designs are
available to the textile designers and textile manufacturers at the click of a mouse.
Application of CAD
The textile designs are the original works of the designers. CAD helps them to visualize and
see their imaginative design in final form without producing any sample swatch. Sometimes,
The customers too provide ideas for designing according to their particular requirement.
These are in the form of painted artwork or fabric samples and sometimes film negatives. The
textile designers, with the help of CAD, convert them into workable designs. For this to be
done, the sample is scanned with the help of either scanners or digital cameras and then they
are edited to obtain the final design.
Textile Softwares
The usefulness of CAD has driven the market to produce specific softwares for different
aspects of textile and apparel manufacturing. If there are softwares for designing footwear,
caps and bags, there are pattern making software too for fashion industry. There are
solutions for sewn goods industry as well as systems for the design of jacquard woven fabrics.
The garment pattern designs are even available in home, expert, and professional versions.
Precision cutting systems, cutting and plotting systems, pattern design, grading and marker
making- you name it and there is a software for every textile related work- this is IT
revolution in textile industry.
Advantages of CAD
This 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.
 Briefly Explain on the Textile Design Systems.
Textile Design Systems
Woven textiles are used by designers and merchandisers for
fabrics for home furnishing and to men-women-children wear. Most
fabrics whether yarn dyes, plain weaves, jacquards or dobbies can be
designed and in fact are invariably used abroad using a CAD system for
textiles. Similarly embroideries are also developed at CAD workstations.
Knitted Fabrics:
Some systems specialize in knitwear production and final knitted
design can be viewed on screen with indication of all stitch formation. For instance a CAD
program will produce a pullover graph that will indicate information on amount of yarn needed
by color for each piece. Another example of the new technology in the industries using a yarn
scanner which is attached to the computer scans a thousand meters of yarn and then simulates
a knitted/ woven fabric on-screen. This simulation will show how the fabric will look like if
woven from that yarn.
Printed Fabrics:
The process involves use of computers in design, development and manipulation of
motif. The motif can then be resized, recoloured, rotated or multiplied depending on the
designer's goal. Textures and weave structures can be indicated so that printout either on
paper or actual fabric looks very much the way the final product will look. The textile design
system can show color ways in an instant rather than taking hours needed for hand painting.
New systems are coming which have built-in software to match swatch color to screen color to
printer color automatically i.e. what you see is what you get.
Illustrations/ Sketch Pad Systems
These are graphic programmes that allow the designer to use pen or stylus on electronic pad or
tablet thereby creating freehand images which are then stored in the computer. The end
product is no different from those sketches made on paper with pencil. They have additional
advantage of improvement and manipulation. Different knit and weave simulations can be
stored in a library and imposed over these sketches to show texture and dimensions.
Texture Mapping: 3D Draping Software
The technology allows visualization of fabric on the body. Texture mapping is a process
by which fabric can be draped over a form in a realistic way. The pattern of the cloth is
contoured to match the form underneath it. The designer starts with an image of a model
wearing a garment. Each section of the garment is outlined from seam line to seam line. Then a
swatch of new fabric created in textile design system is laid over the area and the computer
automatically fills in the area with new color or pattern. The result is the original silhouette
worn by original model in a new fabric.
Embroidery Systems
The designs used for embroidery can be incorporated on the fabric for making garment.
For this special computerised embroidery machines are used. Designers can create their
embroidery designs or motifs straight on the computer or can work with scanned images of
existing designs. All they need to do is assign color and stitch to different parts of the design.
This data is then fed into an embroidery machine with one or multiple heads for stitching.
Weaving:
Weaver's delight, a comprehensive tool kit for the technically discerning and a very
simple and powerful CAD system for the visualiser or weaving novice. Design Desk handles
weaves, yarns, patterns and construction parameters to instantly simulate realistic fabric on
screen. Further it allows you immense flexibility to alter, try 'what if' scenarios in enhancing the
concept you initiated
Yarn development and Management
Designed for the ease of use and
strong facilities, the Yarn Development
Module creates all types of yarns such as
- dyed, fancy, melange, slubs, loop, etc
or combination of different fancy effects.
Different type of fibers, twist per inch
and direction can be specified to ensure
ideal simulation environment. Simple
color controls to research the ideal match
and also standard color palettes are
accessible.
The developed yarns can be visualised in real time for evaluation and interactive changes. Also
fabric effect of yarn developed can be simulated. The Yarn can finally be saved in an efficient
yarn management library for easy retrieval and usage with count and cost parameters.
Weave Creator
Defining draft, peg plan can be done numerically or directly drawing on point paper.
Simple to use cut, copy, paste, mirror tools etc are supported. Weave book manages library of
weaves and provides controls for creating complex weave structures by combining weaves.
Advanced auto weave generation facility provides for creation of different design effects within
the same draft order while changing the Lifting plan. Auto weave insertion facility available for
integrating dobby effects directly onto a design in ornamentation or extra warp mode.
Design Creation
Design patterns can be numercially
specified VIDE Direct draw facility provided
wherein patterns can be specified and scaled
online. Weft pattern is adjusted automatically
considering the EPI / PPI aspect ratio.
Drag and drop operation to specify warp and weft
yarns. Simple and graphical user interface enables
you to easily access all designing control and
design creation seems a song.
Realistic Fabric simulation is generated instantly combining weaves, design patterns, yarns
count and construction parameters defined. Simulation window can be expanded to develop 8
matching’s for comparative evaluation. Advanced
facility to generate matching automatically.
Auto Design Generator
Powerful features are designed to
automatically create patterns based on your selected
design, and parameters to auto generate an infinite
number of design variations instantly. This enables
you to respond to customer requirements in no time
enhancing bookings.
The yarn percentages can be specified enabling Auto
generation to be used for exhausting yarn dead stock. Controls such as size of design, stripe
width range, percentage usage of yarns, pattern styles contribute to innumerable design
generation.
Auto Color Matching
Design Desk allows you the liberty of choosing the apt set of color ways for a design
under development. It takes into account your current yarn library, so that you what is created
can be manufactured with yarns available in house.
Color Swapping
A yet another tool which allows you to generate
options by way of switching the order of yarns being
used in the warp and weft. It keeps intact the well
thought out color scheme and generates
innumerable options for you to select from.
Simulation of Fabrics
Presenting your concepts in a realistic way
at a click of a button and no extra cost is
what this feature aims at be it an internal
evaluation or a sales presentation, a good
simulation is the acid test of your efforts.
Simulation is further enhanced by using
yarns created or scanned directly into the
library. The yarn editor allows you to work
on parameters such as twist, colors,
thickness, etc to generate chenille, fancy,
slubs, melanges, twisted, and all types of
yarn effects.
You can vary the different parameters of a design or edit the design and observe the result
instantaneously. The simulated output can be further tested on a 3D CAD system.
Output
Finally Design Desk generates:
A detailed weaving instruction plan along with
weight and cost calculations.
Selvedge balance facility is provided to ensure
that the design is balanced on both selvedge
sides.
A single, multi design, multi matching
simulations are printed with true to life
realism. Facility to print patterns and color
pallette augments the utility of the CAD
system. Simulation effects are further
enhanced with the plinking effects of the
printouts.
Many more facilities are provided to enhance
the presentations.
Computerized Knitting
Computer Aided Design (CAD) and Computer-Aided Manufacturing (CAM) have
revolutionized the knitting industry. The 1970s saw the introduction of CAD/CAM systems.
Designers used the CAD system is to create product designs and these were transferred to CAM
machines to manufacture the final product. CAD/CAM technology replaced the mechanical
patterning and shaping devices on machines with electronic controls. These systems enabled
companies to respond quickly to changes in demand. New designs could be set up using CAD
and quickly produced on the CAM machine. Though manually operated flat and V-bed knitting
machines are still used, computerized technology is also preferred.
Initially, this system was expensive and only the major companies could afford it. However, in
the 1980s and 1990s CAD/CAM fell in price and even the small and medium sized companies
invested in this new technology. The introduction of this technology enabled companies to
work globally, and on a fast scale.
Introduction of Whole garment Knitting
Side by side with the CAD/CAM knitting technology, the process of whole garment knitting was
introduced. Cutting fabric into shapes and then stitching the pieces together to create garments
has been in practice since the eighteenth century. In the 1970s companies researched more
efficient technologies which could produce a complete garment in one process without the
need for sewing. Without the loss of fabric associated with cut and sew techniques, garments
could be knitted quickly. This was the "Whole garment Technology" which was further
developed in the 1990s by Shima Seiki of Japan. Shima Seiki achieved this advancement in
knitting technology by developing the slide needle. The slide needle was the result of research
of the latch needle and the knitting process.
Whole garment knitted clothes provide greater comfort than cut and sew clothes. The absence
of seams means that the garment can fit close to the body and stretch more easily. Whole
garment machines are also capable of producing complex designs. 2D knitted fabric is replaced
by 3D knitwear, shaped and pleated as required.
Part- C
 Explain on the Digital Printing on Knitted Fabrics.
Digital Printing on Knitted Fabric
With the advance of science and technology, textile printing on knitted garments has been
dominated by screen printing technology. Advances in digital inkjet printing technology during
the 1990's and early 2000's have resulted in knitting machines that can cost-effectively transfer
designs directly from a computer and print onto fabric.
VARAD digital textile screen printing machine, which has the highest accuracy and best
repeatibility.


Its robust cast iron body ensures longest life.
Other salient features include high production and power saving due to use of latest
digital servo drives.
 The screen printing machine includes an efficient and economic dryer. It is simple to
operate with user-friendly aspects, entailing less maintenance.
 It has special features for knit goods printing.
Gen 740TX/C-Digital textile printer



It is able to directly print on most kind of fabrics including silk chiffon, stretchable fabrics
such as knitted fabrics, even some spandex.
Digital Textile Printer enables us to produce strike-off within a day and guarantee
professional textile printing and high profit-business in high end fashion industry, home
furnishing and decorative fabric markets using garments, curtains, beddings, art walls,
sofa and cushions.
It is able to produce a sample within a day with much lower cost than traditional way.
CAD 3D
A versatile and powerful presentation tool for communicating fabric design concepts on the
final application viz. garments, furnishings, curtains, etc. any object, model or area in the image
can be redesigned in 3D environment and then new design range or colors applied. to give a
uniquely realistic result. This texture mapped images makes your sales team and customer
realise marketability of your concepts. Here goes a brief on functioning of Design 3D and its
advantages.
Screen Authoring
3D surfaces or depth dimension are extracted from 2 D scanned images, photographs. Light
source, viewing distance, shading information, etc are effectively defined and stored in 3DP
formats. Set of tools that are user friendly are provided, for the task of generating grids and
selections can be done with multiple options such as freehand, rectangular, etc.
Multiple grids can be created for different segment areas to provide for the mix and match
creations. Facilities to edit the mesh have been provided to give the finishing touches to the
image authoring so that the final output exacts to your imaginations. The mesh can be rotated,
extended, and bent around the edges making your working extremely ductile. Additionally you
can introduce new or remove fold marks so that the mapped image zeroes onto the reality.
Texture Mapping
Drag and drop your designs on the image to create
fascinating and realistic 3 Dimensional texture
Mapping. With tools like wrap around you can
move the draped texture to set it at the right
angles. Dimension of the 3 D object can be defined
so that the fabric size mapped is in proportion and
number of repeats is automatically managed.
An intelligent Library management feature, ATLAS
graphically categorizes the 3dp images into unique
themes such as interior, curtains, beds, models,
men or women wear, table linen, etc.
Atlas also manages various parameters of fabric designs as different collections - plaids, stripes,
floral, historic, geometric, abstract, modern, etc …for subsequent retrieval. Smart Slider hosts
additional functionality to enhance the presentation post-draping and visualise the effect
online in the 3D environment image.
You can change the dimension of the design
Heighten visual effects by fine tuning lightness of fabric, textures, etc ...
You can instantly try out different color ways of the design online.
Applications




Garment Draping
Transform your studio/monitor to a catwalk.
This feature allows you to drape digital photogragh of styled garment onto a live model.
Creating a live presentation.
3D Runway designer is a 3D draping cloth simulation and modeling engine that enables textile
designs to be applied to a specific type of fabric and draping, weight, volume, density, etc.
properties of the fabric can be programmed in to simulate the real thing. This is used for
garment draping and 3D visualization. The fabric is simulated on to the garment pattern and the
model can be placed into static poses that can be captured from a 360 degree angle.
3D Runway Creator for Modulate enables the user to use a wide range of parametric avatar
mannequins that have 40 adjustable body measurements. The potential client gets to see
either a layout containing multiple front, back, side views or an animated runway scene with
the fashion avatar wearing the fashion prototype “before it’s manufactured.” Once the client
receives the video clip of the fashion prototype – they can easily request modifications to the
design prototype. This fully integrated 2D>3D>2D system can transform the fashion product
development process by saving valuable development time.
NEHRU ARTS AND SCIENCE COLLEGE
THIRUMALAYAMPALAYAM -COIMBATORE
DEPARTMENT OF COSTUME DESIGN AND FASHION
STUDY MATERIAL
COURSE
: III-B.SC (CDF)
SEMESTER
: V
SUBJECT
: COMPUTERS IN GARMENT INDUSTRY
UNIT
: IV
LECTURER NAME
: V.S.KARPAGAVALLI
Part – A
1. Computer is used to increase accuracy, productivity, and manage information.
2. The CAD offers MTM software (made to measure) which allows manufacturers and
retailers to develop in to the rapidly growing area of mass customization.
3. Most of computer lay planning programs also require the warp threads of the fabric to
be displayed horizontally.
4. Suppression is the reduction of surplus fabric to obtain a closer fit using darts, seams,
pleats or gathers.
5. Garment balance is known as the hang of the garment around the body .
6. Ease allowances is a tolerance which is added to the body measurements.
7. The patterns are stored within the Accumark database and are usually displayed within
the PDS2000 software module.
Part- B
 Briefly explain on CAD in Pattern Making and Grading.
CAD in Pattern making and grading- system description- information flow-process involved in pattern
making, process involved in pattern grading.
CAD IN PATTERN MAKING AND GRADING
INTRODUCTION:
Computer is used to increase accuracy, productivity, and manage information. This removes the
time consuming tasks of cutting card patterns and planning and drawing markers by hand, and the
duplication of hand written instruction. This computer technology has enabled the clothing design,
pattern construction and product development to be integrated into a more continuous process.
Features

CAD systems enabled the pattern technologist can construct and grade the patterns
simultaneously. The sample garment can be viewed three dimensionally in simulated fabric.

The cost of the garment can be calculated from a computer lay plan of the patterns pieces on
the fabric for utilization.

Cad brings a more structural and systematic approach to the pattern cutting and garment
construction processes.

The CAD offers MTM software (made to measure) allows manufacturers and retailers to develop
in to the rapidly growing area of mass customization.

MTM simplify the customization of a garment; by automate the garment development through
the point of manufacture. This giving the ability to manufacture single garments at mass
production speeds and avoids the high cost usually associated with single garment production.

MTM designed to integrate with existing CAD modules, allowing quick and easy of customer
details, body measurements and customer orders. Information is linked to pattern making
software, marker planning, plotters and single ply cutters.
Pattern making:
Pattern represents the two dimensional component parts of a garment. These are used to guide
for cutting the fabrics, which when sewn together forms a 3-dimensional garment. The creation of these
patterns is the technique of pattern construction (or) pattern making. Pattern construction is the part of
the garment design process and product development. The pattern can also be considered as a
foundation for garment construction.
Information flow
Position of patterns
Creating pattern shapes
Techniques for constructing pattern shapes
Block pattern construction
Testing the block patterns
+y
Positioning of patterns:
-x
The pattern is identified by the computer on the horizontal
x-axis and vertical y-axis. The majority pattern piece program consider
-y
that the warp grain line of the pattern piece runs horizontally on the x-axis,
both on the digitizing table and monitors visual display. Computer grading
also requires horizontal reference line which in most cases is the warp grain line running through the
length of the garment. Most of computer lay planning programs also require the warp threads of the
fabric to be displayed horizontally.
+x
CB
CB
This shows the position of pattern with grain line for computer use.
Part- C
 Briefly explain on the techniques for producing Patterns in computer.
Creating pattern shape by computer
Creating a square, rectangle or circle by most computer program is generally requiring an
interactive drawing using a mouse or stylus. The shape can be produced by a series of points that the
computer automatically joints into a curve. If the curve line is not to required shape or length it can be
modified by either moving the points or using a smoothing similar function.
The computer uses CAD provides PDS for the pattern making functions ( PDS- Pattern design
system). The pattern technician uses PDS tools to create the desired shape of pattern and copying useful
curved lines such as the neck, armhole, sleeve head and skirt seam. The selected curves are placed
within a rectangle, when creating a new pattern these lines can be copied and placed in the new
pattern. The angle of the line can be altered by pivoting or rotating using 2D & 3D models of CAD
system.
While pattern making the following aspects are considered
1. Garment balance – the hang of the garment around the body is known as garment balance. A
well balanced garment hangs in the correct relationship with the wearer’s size, contour and
postures.
2. Suppression – is the reduction of surplus fabric to obtain a closer fit using darts, seams, pleats or
gathers. This controls the shape of the garment according to the contour of the body.
3. Ease allowances- it is a tolerance is added to the body measurements that is generally known as
ease allowance. This is because a garment has to be larger than the wearer to allow for
movement and expansion. In CAD software it contains a tool called PDM (Product data
management) allows the pattern marker to take the information about the measurement
specifications and it is automatically provided the ease allowance for the particular pattern.
4. Influence of the fabric – the dimensional of the fabric influence the garment balance, eases
allowance and suppression. To maintain the correct garment balance the positioning of the
fabric grain line is important. By using the PDS of CAD program the pattern has to be drafted and
then tested.
Techniques for constructing pattern shapes:
4 basic techniques are available
1. Modeling
2. Drafting
3. Suppressing
4. Flaring
Block Patten Construction Technique:
With the designer sketch the pattern maker begins the pattern making process called block
pattern or flat pattern design. It is constructed according to the measurements for the centre base size
of size range. The newly constructed block has to be tested by converting it into a garment for correct
fit. These are permanent record of the correct fit.
The advantage of PDS (Pattern Design System) within a CAD program is that the blocks can include all
grading for other sizes. The CAD uses another program CGMM (Computer Grading and Marker Making).
This carries the grading function of other sizes automatically when the new style pattern is created.
Consequently pattern making and grading are completed in one operation.
Testing the block patterns:
CAD technology offers customization and Made to Measure in the apparel industry (MTM). It
has a great impact on garment manufacturers, as it enabled them to produce designs tailored to
individual requirements. The computerized MTM pattern drafting software is implemented by either
programming traditional tailor’s code method or applying alterations to standard graded patterns. The
pattern data base for different figurations can be extended gradually in order to improve the speed and
efficiency of CAD production. The patterns are stored within the Accumark database and usually
displayed within the PDS2000 software module.
Advanced 3D Pattern Design Systems:
Developments in the Computer Aided Design (CAD) for fashion clothing and visualization have
been realized in the development of 3D software. The creation of 2D pattern shapes that can be
wrapped around a virtual mannequin fit nicely within the 2D CAD pattern development application used
within the industry. Gerber technologies are now offering the APDS-3D virtual draping program, which
has been developed by Asahi of Japan. Open system architecture allows the APDS-3D software to
connect seamlessly with the PDS-2000 pattern models enabling pattern, makers to import styles and
models, thus making the pattern modification easier to achieve. Development within 3D body scanning
systems capable of producing anthropometrics data offer a direct link to 3D design and pattern making.
A digital representation of a tailors mannequin created by means of a 3D digitizer is the start point for
further developments combined with improvements in body scanning techniques, a true representation
of the human form can be realized. From the new personalized mannequin, block patterns can be
created automatically. These can be viewed in PDS2000, 2D format, and either stored or modified to
create a new style. Commercially manufacturers use block patterns that have developed in 2D. After
the pattern making it is transferred to CGMM to further grading the patterns. By block patterns the CAD
system further provide lay planning and marker making plans to minimize the fabric wastages.
NEHRU ARTS AND SCIENCE COLLEGE
THIRUMALAYAMPALAYAM -COIMBATORE
DEPARTMENT OF COSTUME DESIGN AND FASHION
STUDY MATERIAL
COURSE
: III-B.SC (CDF)
SEMESTER
: V
SUBJECT
: COMPUTERS IN GARMENT INDUSTRY
UNIT
: V
LECTURER NAME
: V.S.KARPAGAVALLI
PART- I
1. Many fabrics are turned round and retain the same appearance and these are designated
“either way” or “symmetrical”.
2. Efficiency of the marker plan: Area of pattern in marker plan/total area of marker plan * 100
3. If small no. of copies are needed, carbon paper can be used known as Carbon Duplicating
4.
Diazo Photographic Method is the master marker drawn by this process which makes as many
copies of the marker required.
5. Define Hectograph Carbon System: The marker is drawn on a paper with a layer of special
hectograph paper underneath it.
6. Laying is the spreading of the fabric into the form of lay by means of manually or mechanically.
7. The cutting process takes very much less time than spreading and some what less time than
bundling. The maximum height must be 7.5cm
Part – B
 Briefly explain the computer application in Laying, Cutting and Marker Planning.
Computer application in fabric defect checking, laying/spreading, cutting marker planning, labeling –
parts and functions. Computerized sewing machines.
COMPUTER APPLICATION IN LAYING, CUTTING, MARKER PLANNING
The first stage in the manufacturing of garment is the cutting of the material into necessary
pattern shapes. These are then joined together by means of seams to create three-dimensional
garments. When a single garment is cut out, the garments pattern is attached to one or two plies of the
fabric in which a way it allows for any special requirements such as matching of the design of the fabric.
The garment parts are then cut out with hand shears, electric cutters or dies.
Where the large quantities of a garment style cut, by means of creating the lays with many no. of plies
of fabric spread over one another above. After the lay formation the fabric must be cut all the garment
pieces for all sizes which have been planned. The marker plan (the pattern shapes) paper of the style
placed on the top of the lay, or the information is stored within a computer system as CAD program and
used to cut by means of using automatic cutter. The sizes that will be cut and the no. of plies, i.e. Fabric
in the lays is determined by the requirements o
f the order for the garments.
MARKER PLANNING
It is the process of producing a layout if the garment style pattern which will show the technical
requirements of the fabric consumption on cutting and the needs of material economy and the marker
utilization.
The Requirement of Marker Planning:

To obtain the minimum fabric usage.

To avoid the imperfection in the production process

To reduce the fabric wastage.

To make the cutting process in to the economical way.

To reduce the time of production

To maximize the profit by means of above all
The marker planner subject to three constraints
1. The nature of the fabric and the desired result in the finished garment.
2. The requirements of quality in cutting
3. The requirements of production planning.
 Efficiency of Marker Planning.
1. The nature of the fabric:
a. Pattern alignment in relation to the grain of the fabric
Pattern pieces normally contains a grain line, the grain line should lie parallel to the line
of the warp in a woven fabric or the wales in a knitted fabric. When the pattern pieces lay across the
piece, the grain line should lie parallel to the weft or course direction. In bias cutting, which is often used
in large pattern pieces as part of the garment style in ladies dressing and lingerie, as well as in small
pattern pieces such as pocket facings and under collars in menswear as a requirement of satisfactory
garment assembly, the grain lines will be at 450C to the warp. The designer of pattern may define a
tolerance of small amount form parallel which allows the marker planner to swing the grain line.
b. Symmetry and Asymmetry:
Many fabrics are turned round and retain the same appearance and these are
designated “either way” or “symmetrical”. There is no special action on the part of marker planner.
More restricting fabrics are known as “one way” or “asymmetrical”. In this case, if a fabric ply is turned
round it does not retain the dame appearance, especially when two opposite way are sewn together.
The marker planner must ensure that the top ends if the pattern pieces, as they will be worn in the
garment all face the same way.
c. The design characteristic of the finished garment:
If we want to produce a complete mirror image repeat, the marker is planned which
uses a half set of patterns, and the required effect is created by spreading the fabrics which places pairs
of plies face to face.
2. The requirements of quality in cutting:
The marker must give freedom of knife movement and not restrict the path of the knife
so that it leads to inaccurate cutting. Now days for cutting, a knife blade is used. A blade cannot turn a
perfect right angles and space must always be allowed for a knife to turn such corners. A pattern count
must always be made at the completion of the planning of a marker to check that the complete style of
patterns has been included. Correct labeling of cut garment part is very essential. It is the responsibility
of the marker planner to code every pattern piece with its sixe ad the marker is planned.
3. The Requirement of Production Planning:
To supply the sewing room with an adequate amount of cut garments at sufficiently
frequent intervals, consistent with availability of fabric and the best utilization of cutting room
resources. The higher lay gives a cutting labor cost per garment, it lower over all cutting time which is
important if the sewing room requires the cut work urgently. The shorter markers are easier for the
planner to work on a highly packed and it is a efficient marker. But for complex garments long markers
generally offer more opportunities for savings than do short ones. If the more sizes that are included in a
marker, the grade is the scope for fabric savings.
Efficiency of the marker plan:
Area of pattern in the marker plan
100
Total area of the marker plan
Part – C
 Explain the Methods of marker planning
Methods of Marker Planning:
1. Manual Marker Plan with full size patterns:
Prior to the advancement of computer technology all makers were produced manually and
planned by working with full size patterns. For many companies this method is still used, because the
modern alternatives or more expensive.
a. Carbon Duplicating: If small no. of copies are needed, carbon paper can be used. In this case 6-8
copies can be made without too great deterioration of in the fineness of the line. The
duplicating has the advantage of low capital and material costs.
b. Hectograph Carbon System: In this, the marker is drawn on a paper with a layer of special
hectograph paper underneath it. This paper transfer blue line on to the back to make one copy
at a time in a duplicating machine. The uses alcohol to wet a plain white paper which is then
passed with the master between two rollers transferring the lines on to the copy. It is a messy
process but many copies can be produced.
c. Diazo Photographic Method: When the master marker is drawn by this process makes as many
copies of the marker as are needed. The master marker and a light sensitive paper are passed
under high intensity ultraviolet light and the lines developed using ammonia vapour. The lines
and other marking on the master marker prevent exposure of the light sensitive paper which
forms the copy and the lines remain visible. By this we can make unlimited no. of copies but it
must require ample ventilation to remove ammonia fumes.
An alternative to making multiples of paper markers, is the creation if a perforated marker from
the initial hand drawn version by means of a punch perforator. This has been used for
upholstery fabrics. The perforated marker is placed on the top of the lay and by means of
special lay powder the pattern lines are transferred to the top ply as a series of dots. Care must
be taken that corners and notch positions are adequately defined.
2. Computerized Marker Planning:
This is an integrated system which includes digitizing or scanning of full size pattern into
the computer. There will be the facilities for pattern adaptation and by inputting appropriate
grade rules, this means to generate all the sizes required. The planner uses a VDU with
keyboard, tablet and data pen, mouse. The planner specifies the exact make-up of the marker
plan, the width of the fabric, the pattern pieces to be used, the sizes to be included and all
pieces constraints to be applied, including any matching of checks. The system produces a
marker plan automatically or interactively. There is no guarantee that the best marker plan will
be achieved, but this is a rapid method of achieving a relatively efficient plan and it has the
advantage of, no necessity of an operator.
A data pen (or mouse), tablet and the keyboard are used to manipulate the pattern
pieces, the tablet which rests on the desk of the operator, represents the display screen and
consists of grid of fine wires immediately below the surface when using a data pen, the pen is
touched in the surface of the tablet and it register a position on the grid which shows as a
position as on the screen. The system finally position the pattern pieces according to the
marking rules specified.
This process enables the planner to produce trial marker very rapidly and accurately.
After selecting the most economical marker plan, the computer will provide an accurate piece
count, calculate a marker plan efficiency percentage and total the length of the pattern
peripheries.

An alternative to the data pen in some systems is the mouse or puck. In this case keys
are pressed to achieve the same effect as pressing the data pen on the tablet.

This is more consistent then with manual, because instructions for grain lines are always
followed, there is no any overlapping and the pattern count is automatic.

It also enables reproduction of pattern copies as many as are required.

It is costlier than that of manual methods, as well as small percentage off savings in
fabric can mean saving large amount of money.

After planning the marker on the compute, the marker planner instructs the computer
to plot the marker automatically onto a paper.

The plotters are commonly used to print the marker onto a paper.

The labels carry bar coded or alphanumeric information.
 Explain the methods of Computerised Laying.
LAYING
It is the spreading of the fabric into the form of lay by means of manually or
mechanically.
The objective of spreading is to place the no. of plies of fabric that the production planning
process has dictated to the length of the marker plan, the color required, correctly aligned as to the
length and width without tension. Most of the garment industry is able to cut garments in bulk and by
doing so achieves the savings in fabric that are available through the use of multiple marker plans and
the savings in cutting time per garment that result from cutting many plies at the same time. By this cost
of cutting and the cost of materials would be reduced.
Spread itself a time consuming operation with the more no. of lays it can consume more time in
total than cutting, especially if the cutting is by computer controlled knife.
The spreading must consider the following s
1. The requirements of the spreading process
2. Methods of spreading
3. The nature of fabric package
1. The requirements of the spreading process:
Spreading must achieve a no. of specific objectives which are below.
a. Shade sorting of cloth pieces :
Lays normally requires more than one roll of fabric and include several colors of roll to
achieve enough plies in total. Generally the cloth pieces are the same color will have been dyed
separately and are not in as exact shade. A garment made from parts cut from these different
pieces would likely to show a shade variation between its different panels. Thus when the
delivery received a no. of rolls of cloth in the same color, they should be sorted into batches
such that shade differences between them are undetectable. This is done by a trained colorist. It
can be easily be done by a computer after measurement of the color has been carried out using
a spectrometer, or a colorimeter, where the different shades of fabrics to be spread adjacent to
each other in the lay, they are separated by a layer of interlacing paper, a roughened tissue n a
bright color which can be seen easily at the edge of each cut stuck and which assists in easy
separation of the plies for bundling.
b. Correct ply direction and adequate lay stability:
This depends on fabric type, pattern shape and the spreading equipment that is
available. The various types of fabric, in terms of surface direction designated as either way –
either way and one way only fabrics, where the pattern pieces have been positioned in a
particular direction in the marker plan, it is essential that the fabric is spread in a way that
maintains that direction. The visual effect of a surface design or fabric construction, problems of
instability with fabrics of special frictional characteristics such as those with nap or pile surface.
This can require that some fabrics are spread with all the plies face up, some with all the plies
face down and some face to face.
As per the pattern shape is concerned, if the pattern pieces which shape symmetrical means the
fabric may be spread face to face. If the pattern pieces are asymmetrical the fabrics spread all
the plies face up or face down.
Alternate plies in different direction; symmetrical pattern pieces; fabric stable face to face
Alternate plies in different directions; fabric stable face up
All plies in the same direction; fabric stable face up
All plies in the same direction: symmetrical pattern pieces; fabric stable face to face
The fabric is being spread by hand or if a spreading machine with a turntable is available, there are four
possible types of spread can be achieved. The spread of spreading depend on the various constraints
described above.
The four types of spread are shown above.
a. For symmetrical pattern pieces, and fabric which is stable spread face to face, the fabric can
be spread along face up and immediately back again face down.
b. For symmetrical & asymmetrical pattern pieces, and fabric which is stable all the same way
up, the fabric can be spread along and immediately back again but the roll must be turned
on a turntable before returning.
c. For asymmetrical as well as symmetrical pattern pieces and fabric which is stable all the
same way up, the spreader spreads in one direction only and “dead heads” to spread the
next ply in the same direction.
d.
For symmetrical pattern pieces, and fabric which is stable face to face, the spreader spreads
in one direction only but after “dead heading “ back, a turntable in required to rotate the
roll before the next ply is spread in the same direction.
c. Alignment of Plies:
Every ply should comprise at least the length and width of the marker plan, but should have
the minimum possible extra outside those measurements. The marker plan is made to fit the narrowest
width. The samples width is usually distributed outside the edge of the marker plan. Plies are centered
and the surplus distributed equally to both edges. Inaccuracy in the alignment could mean that plan do
not cover the whole area of the marker plan and parts of some pattern pieces would be missing when
cut.
d. Correct ply tension:

If the plies are spread with too slack a tension they will lie in ridges irregular fullness.
 If plies are spread in a stretched state they will maintain their tension, after cutting or
sewing they will contract thus shrinking the garment parts to a smaller size than the pattern
pieces.
 Thus the use of spreading machine with possible feed to give tension-free spreading
normally obviates stretched plies being bound into the lay.
e. elimination of fabric faults:
Fabric faults (flaws, holes, stains, etc.) may be identified and additional faults may be
detected during examination of the fabric by the garment manufactured prior to spreading, in
this case a ‘string’ or plastic tag is attached to the fabric edge level with the fault. The simplest
way to achieve this is by creating a splice. The spreader cut across the ply at the position of the
fault and pulls back the cut and to overlap as far as the next splice mark. Splice marks are
marked on the edge of spreading table prior to spreading by reference to the marker. How
much fabric is wasted when a splice is made thus depends not just on the size of the fault but on
the size of the garment panels in that part of the marker.
f. Elimination of static electricity:
In spreading of fabric containing manmade fibers, friction may increase the charge of static
electricity in the fabric. Then the operator feels difficulty of laying due to repulsion of those plies
according to how they changed. So humidity in the atmosphere of the cutting room may also be
increased thus allowing the static electricity to discharge continuously through the atmosphere.
g. Avoidance of distortion in the spread:
A layer of glazed paper, laid glazed side down, is normally placed at the bottom of the
spread. This helps to avoid disturbing the lowest plies of material in the spread when the base
plate of straight knife passes underneath and also given stability to the lay if it is to be moved on
a floatable table and also prevent snagging.
h. Avoidance of friction of plies during cutting:
During cutting the cut edges of thermoplastic fiber fabric may fuse together due to friction
causes the knife to become hot. For this ant fusion paper (which contains lubricant) which
lubricates the knife, thus the temperature of the blade reduced.
Methods of Spreading (Laying)
There are two methods
1. Spreading by hand
2. Spreading using a travelling machine
Spreading by hand:
The fabric is drawn from its package as a roll, may be supported on a frame and carried along
the table where the end is secured y weights or a clamp. The operators work back from the end, aligning
the edged and ensuring that there is no tension and that there are no wrinkles. The ply is normally cut
with hand shears or a powered circular knife mounted on a frame.
Ex. Checks, crosswise, stripes, other regularly repeating patterns
Spreading Using a Travelling Machine:
This machine carries the piece of fabric from end t to end of the spread, dispensing one ply at a
time onto the spread. Their basic elements are frame or carriage, wheels with travelling guide rails, a
fabric support, and guide collars to correct the unrolling of the fabric. The operator clamps the free end
of fabric in line with the end of the spread, pushes the spreader to the other end, cuts off the ply in line
with that end, clamps the beginning of the next ply, pushes the spreads to the other end and soon.
The advent of microprocessor control has enabled the development of more automatic function
on spreading machines. By this we can pre-set the no. of plies, emitting an audible signal when it has
reached the selected numbers or come to end of a piece of fabric. Automatic turn tabling gives
automatic spreading face to face. With robotic spreading, when the piece is finished, the spreader
returns to an auto-lifter at the end of the table. It repeats the process until it achieves the required no.
of plies.
 Explain the methods of Computerised Cutting.
Cutting
It includes the activities like marker planning, spreading and preparation for sewing as well as
being used to refer to the actual cutting out of garment pars from the lay.
Objective of Cutting:
Is to individualize the fabric parts as replicas of the pattern pieces in the marker plan. By this
certain requirements must be fulfilled.
1. Precision cutting
2. Clean edges
3. Un scorched, un fused edges
4. Support of the lay
Method of Cutting:
The following cutting systems are currently used
1. Hand shears
2. Straight knife
3. Round knife
4. Band knife
5. Notches
6. Drill marker
7. Computer controlled cutting systems
The above cutting systems are used manually except the computer controlled system. Now we
can see the computer controlled system in detail.
Computer controlled cutting systems
This system uses the marker generated on computerized marker planning system. The marker
data is transferred to the cutting unit by means of tapes, floppy discs, directly from the marker
planning system itself. This method provides the more accurate possible cutting, at high speed. A
typical computer cutting system has a table with a cutting surface consisting of nylon bristles which
support the fabric lays but are flexible enough to permit penetration and movement of the knife blade,
which is supported only at the top. The carriage supporting the cutting head has two synchronized
servo-motors which drive it on tracks on the edges of the table. A third servo-motor positions the
cutting head on a beam across the width of this carriage. These two movements are co-ordinate to give
a knife position at any point on the table. The cutting head contains a knife to position it at a tangent to
the line of cut on curves. A sheet of airtight polyethylene covers the top of the lay which assist the
creation of a vacuum and allows significant compression of the lay. A control cabinet houses the
computer and the electrical components required to drive the cutter, its carriage and the vacuum
motor.
The spreader spreads the lay on a conventional cutting table quipped with air floatation. Paper
is spread below the bottom ply so that the lay can be moved onto the cutting table without distortion
and so that the bottom plies are supported during the cutting operation. After loading the disc into the
computer, the operator positions the cutting head origin light over the corner of the spread. This
provides the computer with a reference point. A lift and plunge feature enables the knife to negotiate
sharp corners and straight or v-shaped notches also be cut. The maximum height is 7.5cm when
compressed. The cutting process takes very much less time than spreading and some what less time
than bundling. It is considered to be the most effective investment for large scale cutting production.