AUTOMATIC DATA CAPTURE

Presented To:

Prof .Dr. Amjad Pervaiz

Submitted By:

Muhammad AslamAdil Farooq

OVERVIEW OF AUTOMATIC IDENTIFICATION AND DATA CAPTURE METHODS

The term automatic data capture is also known as automatic identification and data capture.

ADC refers to the technologies that provide direct entry of data into a computer or other microprocessor controlled system without using a keyboard.

Many of these technologies require no human involvement in the data capture and entry process.

ADC are used to collect data in Material handling Manufacturing Service Industry

APPLICATION OF ADC IN MATERIAL HANDLING Material handling systems

Shipping and receiving Storage Sortation Order picking Kitting of parts for assembly

APPLICATION OF ADC IN MANUFACTURING Application include

Monitoring the status of order processing Work-in-process Machine utilization Worker attendance Inventory control Warehousing Other measures of factory operations

APPLICATION OF ADC IN SERVICE SECTOR Distribution centre operations Mail and parcel handling Patient identification in hospitals Check processing in banks Security systems Transportation Education sector

MANUAL COLLECTION AND ENTRY OF DATA This involves recording data on a paper and later

entering them into the computer by means of keyboard.

There are several drawbacks to this method

Errors occur in both data collection and keyboard entry of data when accomplished manually. The average error rate of manual keyboard entry is one error per 300 characters.

In manual methods, there is a time delay between when the activities and events occurs and when data on status are entered into computer. Manual methods are more time consuming.

The full time attention of human workers is required in manual data collection and entry, with associated labor cost.

AUTOMATIC IDENTIFICATION METHODS

Nearly all of the automatic identification technologies consists of three principal components,

Encoded data: A code is a set of symbols or signals representing alphanumeric characters. When data are encoded, the characters are translated into a machine-readable code. A label or tag containing the encoded data is attached to the item that is to be later identified.

Machine Reader or Scanner: The device reads the encoded data, converting them to alternative form, usually an electrical signal.

Decoder: This component transforms the electrical signal into digital data and finally into the original alphanumeric characters.

AUTOMATIC IDENTIFICATION METHODS

ADC Technologies can be divided into the following six categories:

Optical: Most of these technologies-use high contrast graphical symbols that can be interpreted by an optical scanner. They include linear and two dimensional bar codes, optical character recognition and machine vision.

Magnetic: Which encode data magnetically, similar to recording tape. The two important techniques in this category are

Magnetic stripe, widely used in plastic credit cards and banking access card

Magnetic ink character recognition, widely used in the banking industry for check processing.

AUTOMATIC IDENTIFICATION METHODS

Electromagnetic: The important ADC technology in this group is radio frequency identification.

Smart card: This term refers to small plastic cards (the size of a credit card) imbedded with microchips capable of containing large amounts of information.

Touch techniques: Such as touch screen and button memory.

Biometric: These are used to identify humans or to interpret vocal commands of humans. They include voice recognition, fingerprints analysis and retinal eye scans.

GOOD REASONS FOR USING ADC Data Accuracy: Accuracy of data collected is

improved with ADC. The error rate in bar code technology is approximately 10,000 times lower than in manual keyboard data entry.

Timeliness: the second reason is to reduce time required by human workers to make data entry. The speed of data entry for handwritten documents is approximately 5-7 characters per second. Automatic identification methods are capable of reading hundreds of characters per second.

Labor Reduction: The time savings in using automatic identification techniques can mean substantial labor cost benefits for large plants with many workers.

BAR CODE TECHNOLOGY

Bar codes divide into two basic types Linear or one dimensional bar codesIn which the encoded data are read using a linear

sweep of the scanner. Two dimensional bar codesIn which the encoded data must be read in both

directions.

LINEAR (ONE DIMENSIONAL) BAR CODES

Linear bar codes are currently the most widely used automatic identification and data collection technique.

There are two forms of linear bar code symbologies. Width modulated In which the symbol consists of bars and spaces of

varying width. Height modulatedIn which the symbol consists of evenly spaced bars

of varying height

WIDTH MODULATED

In linear width – modulated bar code technology, the symbol consist of wide and narrow colored bars separated by wide and narrow spaces .

The pattern of bars and spaces is coded to represent numeric or alphanumeric characters.

Height Modulated The only significant application of the height

modulated bar code symbologies is in U.S. postal service for zip code identification.

BAR CODE READERS

CONTACT BAR CODE READERS They are hand held wands or light pens

operated by moving the tip of the wand quickly past the bar code on the object or document.

The wand tip must be in contact with the bar code surface or very close proximity during the reading procedure.

In factory data collection application, they are usually part of a keyboard entry terminal.

The terminal is sometimes referred to as stationary terminal in the sense that it is placed in a fixed location in the shop.

CONTACT BAR CODE READERS (CONT.) They are also available as portable units that

can be carried around the factory or warehouse by a worker.

They are battery powered and include a solid – state memory device capable of storing data acquired during the operation.

NON-CONTACT BAR CODE READERS

These readers focus a light beam on the bar code and a photo detector reads the reflected signal to interpret the code.

The reader probe is located a certain distance from the (several inches to several feet) during the read procedure.

NON-CONTACT BAR CODE READERS

Fixed beam readers: these are stationary units that use a fixed beam of light. they are usually mounted beside a conveyor and depend on the movement of the bar code past the light beam for their operation.

NON-CONTACT BAR CODE READERS

Moving beam scanners : they use a highly focused beam of light , actuated by rotating mirror to traverse an angular sweep in search of the bar code on the object.

Lasers are often used to achieve the highly focused light beam.

MOVING BEAM SCANNERS

Stationary scanners : they are located in a fixed position to read bar codes on objects as they move past on a conveyor or other material handling equipment.

They are used in warehouses and distribution centers to automate the product identification and sortation operations.

MOVING BEAM SCANNERS

Portable scanners: these are hand held devices that the user points at the bar code like a pistol.

The vast majority of bar code scanners used in factories and ware houses are of this type.

BAR CODE PRINTERS

In some bar code applications, the labels are printed off-site in medium to large quantities for product packages and the cartons used to ship the packaged products.

Bar codes can be printed on-site by methods in which the process is controlled by microprocessors. These applications tend to require multiple printers distributed at locations where they are needed.

BAR CODE PRINTING TECHNOLOGIES

Following printing technologies are commonly used.

Dot matrix Ink-jet Direct thermal Thermal transfer Laser printing Laser etching

DOT MATRIX

In this technique the bars are printed by overlapping dots to form wide or narrow bands.

It is a low cost technique , but the quality of the printed bars depends on the degree of overlap , accordingly, there is a lower limit on the size of the bar code.

INK-JET

Like dot matrix, the ink-jet bars are formed by overlapping dots , but the dots are made by ink droplets.

DIRECT THERMAL In this technique , light-colored paper labels

are coated with a heat sensitive chemical that darkens when heated.

The printing head of the thermal printer consists of a linear array of small heating elements that heat localized areas of the label as it moves past the head , causing the desired bar code image to be formed.

Bar codes by direct thermal printing are of good quality ,and the cost is low.

THERMAL TRANSFER

This technology is similar to direct thermal printing , except that the thermal printing heads is in contact with a special ink ribbon that transfers its ink to the moving label in localized areas when heated.

LASER PRINTING Laser printing is the technology that is widely

used in printers for personal computers. In laser printing , the bar code image is

written onto a photosensitive surface (usually a rotating drum) by a controllable light source (the laser), forming an electrostatic image on the surface.

The surface is then bought into contact with toner particles that are attracted to selected regions of the image.

The toner image is then transfer to plain paper and cured by heat and pressure.

High quality bar codes can be produced by this method.

LASER ETCHING

This process can be used to mark bar codes onto metal parts . The process provides a permanent identification mark on the item that is not susceptible to damage in the harsh environments that are encountered in many manufacturing processes.

TWO DIMENSIONAL BAR CODES

Two dimensional symbologies divide into two basic types

Stacked bar codes Matrix symbologies

STACKED BAR CODES The first 2-D bar code to be introduced was a

stacked symbology. It was developed in an effort to reduce the

area required for a conventional bar code. But its real advantage is that it can contain

significantly greater amount of data. It consist of multiple rows of conventional

linear bar codes stacked on top of each other .

MATRIX SYMBOLOGIES

A matrix symbology consist of 2-D patterns of data cells that are usually square and are colored dark (usually black) or white.

There advantage over stacked bar codes is their capability to contain more data.

Applications of the matrix symbologies are currently found in part and product identification during manufacturing and assembly.