burak onurlu (2008), radio frequency identification (rfid) implementations in logistics, ytu,...

7/31/2019 Burak Onurlu (2008), Radio Frequency Identification (RFID) Implementations in Logistics, YTU, Istanbul_Summary

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YILDIZ TECHNICAL UNIVERSITY

THE FACULTY OF MECHANICAL ENGINEERING

INDUSTRIAL ENGINEERING DEPARTMENT

FINAL PROJECT

Radio Frequency Identification (RFID) Implementations

in Logistics

Advisors : Asst. Prof. Umut TUZKAYA

YTU No : 05061604

Name, Surname : Burak ONURLU

stanbul, 2008


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TABLE OF CONTENTS


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1. INTRODUCTION

RFID (Radio frequency identification) is a technology enables objects or living creatures

to be identified with radio frequencies. RFID technologies which are mentioned more

frequently day by day via various conferences and researches, have been used for so long

by many of the worlds leader firms in every level. But, in recent years, not only big firms

but also small and medium sized firms have launched RFID implementations to be

involved in their systems. Nowadays RFID technology brings various advantages in every

field, especially in logistics and enables; processes to be fast and productive, automating

by minimizing the human factor in operations, cost reduction and an increase in customer

satisfaction.

Enterprises of our country have also kept up with this development, Turkeys first and

only RFID Research and Development Center has been established in Istanbul Technical

University, many firms consulting and supporting in RFID field started operating.

However, unfortunately our country is rather a lot arrear in practice beside the giant

projects of the world. In the researches I have done during my thesis study, lack of

Turkish resources and RFID implementations in Turkey reveals this truth. There is still

only one post graduate thesis about the RFID systems in the database of the Higher

Education Council. When it is considered that logistics sector is one of the fast-moving

and growing sectors of Turkey in recent years, importance of RFID technology to be

applicable in our country, thought of RFID technology will be a standard implementation

in every field in recent future shows the significance of this study.

In the thesis, besides comprehensively examining of RFID systems technically, also some

predictions are made regarding the present situation and future position of RFID systems.

Comparison with barcode systemswhich considers RFID systems as destructive

technologyunderlies the study.

In addition to this, after implementation levels of RFID project are told, two different

world-class RFID logistics projects which have been applied in the two leader firms of

different sectors in Turkey, have been examined comprehensively. Projectsfirst of

which is storage location verification and latter is the real-time resource management

system, are involved in the thesis study in practice after theoretic and technicalinformation.


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8. RFID IMPLEMENTATIONSEven though RFID systems and system implementations are not a brand new technology,

as they are on ever-developing level, there is a lack of information not only in Turkey, but

also in the world. Not only the firms which apply the implementation in their systems, but

also the firms which supply and consult technology, do not want to share the information

they have.

In this phase of the project, RFID systemswhich are applied by one of the worlds

leading tire manufacturer and biggest logistics firms of Turkey, will be mentioned. Theseprojects are just as successful as similar implementations in world and also they are the

two most extensive RFID projects applied in Turkey.

8.1 RFID Storage Location Verification System8.1.1 Problem Definition

One of the worlds leading tire manufacturers carries out the tire production and storage

operations in Turkey in their Izmit facilities. A store of 7.000 square meters is inadequate

for the manufacturer, so firm completed the construction of its new store of 52.000 square

meters. However, even in the present store of 7.000 square meters, problem of placing tire

palettes is experienced. It is anticipated that this problem will get even bigger in the new

store consisting of 4000 locations. Forklifts are being used in storage operations and

forklift operators warehouse 7 to 10 tire palettes by superposing.

After the newly produced tire or any other tire palette is loaded on a forklift for the

delivery, by an operator, he moves the palette to a related place in accordance with the

directions given by another operator.

This is where the mentioned problem occurs. Forklifts erasing the numbers on the floor

and making the floors unclean with their weights, operators misunderstanding of the

delivery addresses of the palettes and/or delivering to the wrong address, operators

misplacing the palettes arbitrarily, brings the problem of stock and planning.

Problems in palette placements;


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- Prevent authorities to know how many requested products are in the stock- Cause products to be lost within the storage- Obstruct products to be found within the storage- Superposing of the palettes causes plenty of time to be spent in re-organizing the

incorrect palette placement. Operator can be obliged to take down 7-8 palettes and

replace them in order to place the undermost palette to its correct place.

In order to solve this problem in palette positioning operations, tire manufacturer firstly

placed barcodes to the floor, but forklifts made barcodes to be at standstill by rubbing

away or polluting them. Decision makers of the tire manufacturer thought of establishing

a RFID system for solving the problem and then it is carried into action.

8.1.2 System DesignSystem wanted to be used in the storage of the tire manufacturer is rather different project

in consideration with the systems applied both in Turkey and in the world. Two forklifts

and an area containing 80 addresses in the present storage will be used for the pilot

scheme.

In the system, RFID tags are embedded inside the concrete as palettes. The minute

operator loads a palette on a forklift; he will read the barcode tag located on the palette,

via manual reader. Address of the paletteswhich is needed to be taken to by a

middleware, will be informed to forklift panel via wireless network. After seeing the

address on the screen, forklift operator will take the palette to the related location and

when it reaches there, RFID reader will read the RFID tag and inform the operator

whether he is in the right place or not, by checking the addresses of the system and of the

RFID tag. Till he brings the palette to the right place, middleware will not send any new

information to the forklift panel. System operation will be explained in detail during

configuration.


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8.1.3 Appliances Used in the System8.1.3.1Readers and Antennas

RFID readers and antennas which will be mounted to the forklifts are ALR-8800 model

readers owned by Alien firm. The reason why this model is selected is because of its high

and incessant ability of reading, its applicability to the whole foundation and its remote

administration capability. Also, its firm software can be updates online instantly and it

supports international standards of ETSI EN 302-208, ETSI-EN 301-489 and ETSI EN

300-220. It also supports international standards of EPC Gen 2 of Globalwhich

determines the safety compatibility of BS EN 60950, BSEN 50364 and the RFID product

standards.

Figure 8.1 A scene from a trial practice of readers and antennas which will be used.

A photograph of reader and antennas taken during a trial practice is seen in Figure 8.1.

Alien ALR-8800 reader protocol can be controlled remotely and has a management function

which is adjustable for different implementations on the XScale/Linux basis. Considering the


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protocols which can be variable in the future, EPC Gen 2 implementation has a structure of

signal functioning which can be re-programmable.

An uploader exists in ALR-8800 and it can upload new configurations to various reading

points, antennas etc. or it can adjust itself according to these configurations by downloading

present configurations which exist here. Thus, it becomes much easier to add a new reader to

a present system. Newly-added reader can work on the present system configuration by

recognizing it. This consolidation feature will provide connection between sensor, indicator

and actuator without the need of any extra equipment and will be a factor which will reduce

the cost.

Another advantage of Alien reader is that its signals are general purpose input-output (GPIO)

which are isolated optically, by this means its signals can be sent both as an input or output.

Also, thanks to the optic isolation, signals can run on loud, humid etc. industrial environment

conditions.

Electronic circuit of the reader is suffused with a resistant steelwork and its connection points

are attached on the steelwork in such a way that it cant come loose even in the high vibrating

environments. During the project, reader is tested in the positions where vibration, high or low

temperature, dust and moisture is intensive and it is observed that no differentnesswhich

would affect the communicationis experienced in the signal level.

Another advantage of the reader is that in case of any power cut or power loss, it can continue

on its latest activity when it is reactivated. In case of any cable wear, rupture etc. which can

happen when forklifts are used too fast by the operators and because of the operating

environments of the forklifts, no information loss will be in the reader. Likewise, during a

power cut in the network connection, reader continues to operate and when the network

connection is re-provided, it continues to send the informationwhich is gathered when it

couldnt be able to reach the networkto the middleware, in full. This is called operating in

autonomous case. Scenarios like power cut and unlinking the network connection are tried

during the project and it is seen that reader works perfectly in the mentioned cases.

Identification of more than 2500 tags and their features are included in the permanent and

unchangeable memory card of the reader. Also, permanent memory can be developed with

software updates. It can be said that the biggest advantage of the reader is software updating


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continuously. Forklift which is used in the storage of the tire manufacturer and which will be

connected to the reader and antennas can be seen in the Figure 8.2.

The only disadvantage of ALR-8800 is that it operates with 2 or 4 antennas in TX-RX way. If

we would have used a single antenna during the project, its mounting would be much easier.

However, we were obliged to attach two antennas under the forklift as it does not support

single antenna. Nevertheless, readerwhich has many connection points, has also the feature

of connecting with any electronic device, besides being full-compatible with

Motorola/Symbol AS400 screen which is found on forklifts.

In addition to these, reader has the features of Dense Reader Mode which enables it to

operate in dense and multi-reader environments and Listen-Before-Talk (LBT) which

prevents reader and other deviceswhich operate with radio frequencyto be clashed with

each other.

Another important advantage of ALR-8800 is that it only operates during the operation in this

project where many forklifts are operating nearby, and it shifts to a sleeping mode when it is

not operating.

Figure 8.2 Forklift which will be connected with reader and antennas


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By this means, number of readers which operate simultaneously in the environment reduces

and reader only operates in the needed time. Table 8.1 shows the features of Alien ALR-8800.

Table 8.1 Features of Alien ALR-8800

Manufacturer / Model Alien ALR-8800

Architecture XScale processor, 64 MB RAM on Linux

OS, 32 MB Flash, Digital Signal Processing,

FPAA

Supported RFID Tag Protocols EPC Class 1 Gen 2, ISO 18000-6c

Reader Protocols Alien Reader Protocol

Autonomous Mode

Upgradeable Architecture for future EPC

protocols

EPC Gen 2 reader architecture

Network Protocols DHCP, TCP/IP, SNTP, DNS, SNMP

Dense Reader Management Dense Reader Mode, Listen Before Talk,

Auto triggering and event management

Frequency / # of Channels 865.6 MHz 867.6 MHz / 10

Channel Spacing 200 KHz


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RF Power 2 Watt ERP

Power Tri-voltage AC/DC power converter; 45

Watts maximum 120 or 240 VAC

Antennas

4 ports for 4 read points; multistatic

topology; circular or linear polarization, 6

meter cables, reverse polarity TNC

connectors

General Purpose Inputs/Outputs 4 inputs, 8 outputs, optically isolated, 0.5

watt current capacity

Dimensions (L) 28 cm x (W) 22.9 cm x (D) 5.6 cm

Weight 2000 gr

Operating Temperature -20C to +50C

LED Indicators Power, Link, Active, Ant 0-3, CPU, Read,

Sniff, Fault (red)

Software Support Java and .NET APIs for Alien Reader

Protocol, Alien Gateway demo and test

software

Compliance: Safety ETSI EN 302-208, EN 301-489, EN 300-

220, EPC Gen 2


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8.1.3.2TagsWe have previously mentioned the weight of forklifts causing uncleanness/eroding away

of the tags. In the project implemented to a tire manufacturer, RFID tags will be

embedded into a concrete and it will be covered with epoxy. Thats why cable type

embeddable tagswhich are produced by William Frick & Company as Smart Mark

brandis used in the project. These are the resistant tags which can be embedded into

palette, concrete, tree, plastic, carbon, etc. and whose performances do not decrease.

Figure 8.3 shows the photograph of tags taken during they are being tested and their

general structure.

Figure 8.3 General structure of the tags which will be used

Chip cable is located in the middle of the tag and it is connected to a RFID antenna until the

cable end. This design enables reader to have 360 degree of reading area and an increase on

the precision of layout order. Reading area of the tag varies by the object it is embedded into

and its embedding distance. It is inserted into a hole which has a similar size with it and which

is drilled with concrete saw. Even though the chosen tag is UHF tag in 915 MHz frequency


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standard, it enables to be adjusted in the requested frequencies. Table 8.2 shows the features

of WF-SM-IN01 and 02 tags which are used in the project.

Table 8.2 WF-SM-IN01/02 General Features

Manufacturer William Frick & Company

Model WF-SM-IN01

WF-SM-IN02

Dimensions 114 mm x 3 mm

152 mm x 3 mm

Frequency 915 MHz Standard

Adjustable based on the project

Standards EPC Class 1 Gen 2 Passive

Functionality Can be embedded into concrete, tree, plastic,

carbon, composites, etc.

Implementation Areas Critical Asset Tracking, Real-time Location

Systems


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8.1.4 System Configuration and Pilot Study

Tire manufacturer still uses Cubic Store Management System software in its system. Cubic

manages, saves and reports the whole processin computer environmentfrom production

and/or acceptance of the product to its dispatch, by using the automatic identification

technologies. Additions are done on Cubic for the placement of palettes in accordance with

the stock methods of evaluation such as FIFO, LIFO etc.

In the first phase of the project, palettes location definers in the Cubic system, in other words,

their addresses, are written inside the tags. The moment operator receives the palette a

command concerning the current stock method of evaluation will be issued to it.

In the second phase of the project, front side of the places where palettes are located are

sawed and tags are inserted in. Figure 8.4 helps you to visualize the application area of the

pilot project, palettes and the locations where the tags will be embedded. On the left side of

the image, the area where the pilot project will take place is showed. A tag containing palette

location for each palette line will be embedded on the red line which is seen on the right side

of the image.

Figure 8.4 Project area, palettes and the line where tags will be embedded.


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Figure 8.5 shows the embedding stage of the tags after the concrete is sawed.

After the embedding stage of the tags, it is carried on with the connecting reader and antennas

to the forklift stage, which is more challenging. Antennas are placed on the fork in the actions

such as palette, monitor tagging. However, because the tags are embedded on the floor in our

project and because the antennas cannot read the tags efficiently when they are on the fork,

base of the forklift is determined as the most convenient place for antenna placement. Figure

8.6 shows the location where antennas are connected to forklifts.

Figure 8.6 Antennas connecting to forklift


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Cables of the antennaswhich are fastened up with strong industrial adhesive tape and

bandsare gathered in one place and a point of support is created in the immobile part of the

fork on a forklift, later these cables are put into the forklift cabinet in order to be connected to

the reader. Most convenient point for the reader is detected as the back of the right side of the

cabinet where operator makes no rise and fall and where the Motorola/Symbol AS400 forklift

screen is located. Power cable connection got completely ready for the test operation of

forklift, after the antenna connections and connecting with the forklift panel. Figure 8.7 shows

the appearance of the forklift after the cabinet mounting is done. We have mentioned about

tags, reader and middleware when we were talking about the general components of RFID

systems in the previous chapters. Placement of the tags and reader in our system is

accomplished. At this phase, system is ready to operate with a command of a middleware.

Middleware communicatesthrough radio frequency, with forklift panel and wireless

network, panel series connection with forklift panel RFID reader, RFID reader tags.

Figure 8.7 Connection of reader to the forklift

When the operator gets on the forklift and starts operating it, forklift screen, antennas and

reader will be ready to operate. When the operator loads a palette to a forklift for production

and/or storage, he will read the palette barcode via remote control manual barcode reader and


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this read barcode information will be sent to Cubic software through wireless network. Cubic

software will inform forklift panel the delivery address of the palette via wireless network,

and the panel will reflect the necessary command concerning the delivery address of the

palette, to the monitor.

As it will be seen in Figure 8.8, Cubic software wants forklift operator to send the palette

whose barcode is readto the address numbered TB1002. The moment the forklift operator

goes to this address, reader will read the RFID tag in the address and tell the operator whether

he is in the correct place or not. Operator will be obliged to take the palette to the correct

address as he will not receive any new command till he find the correct address. Figure 8.9

shows that the operator takes the palette tagged as 007230 RFID to TB1001 by mistake,instead of taking it to TB1002 address. And the system warns him indicating that he is in the

wrong place. Operator will continue to receive this warning until he takes the palette to

TB1002.

Figure 8.8 Screen that middleware gives its first command to the operator

Figure 8.9 Wrong location screen


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And when the operator takes the palette to the correct place, he will see the correct location

screen which sends green light, then he will move for his next duty.

Figure 8.10 Correct location screen

8.1.4 Data and Evaluations Acquired as a Result of Pilot StudyAlthough it is in the beginning of a pilot stage, it is pretty successful according to the

datas acquired by the end of a month. First datas acquired in the project application done

with 80 addresses and 2 forklifts, are as follows;

- 993 out of 1000 palette placements were successful.- It is detected that failed readings are caused by the inconvenient settings of tags,

incorrect frequency adjustments and entering wrong address information. These are

also corrected.

- Decision maker position of human factor is completely abolished in palette placementsand automation is enabled.

- As it is detected that which product is in which address, probability of loosing aproduct in the stock is prevented and palette carriage actions decreased from 11minutes to 6 minutes.

- Placing a palette to a right place was detected as 820 palette per 1000 palette beforethe system is established. It can be clearly seen how high this rate is in a full-scale

storage. 0.993 palette rate acquired in the new system provided a 17.3% rate of

improvement in the productivity. It can be clearly said that, non-carrying cost caused

by not being able to find the products, is decreased at least at this rate.


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Unit cost of the tag used in the pilot practice of the system is 6 USD, and unit cost of the

reader and antennas per each forklift is 3.350 USD. In this case, tag cost for 4000 adress is

24.000 USD, cost for forklift is 100.500 USD, therefore the total cost will be 124.500 USD.

Even though the systems investment seems high at first, besides its advantages, its cost will

be stabilized, in other words, tag, reader and antennas will not bring any more cost in short

and medium terms. This can be considered as the biggest advantage of the system.

Time elapsed during the movement of the palettes for sale, shipping etc. is decreased at 46 %

rate. Without a shadow of a doubt, the biggest factor of this recovering is the abolishment of

the wasted time experienced when 1 to 9 palettes are taken down one by one because of the

misplaced palette after superposing themas this is mentioned in the problem definition.When the effect of the time gained from here to total running hours is considered, it can be

easily said that efficiency of the storage is improved.

After tire manufacturer carries out its pilot practice a bit longer, it plans to launch a location

verification practice in whole storage via RFID system. After this system, transformation of

palette barcodes into RFID tags is considered. However, besides being only in the beginning

of the planning stage in this project, some constraints such as; appropriate tag selection since

the palettes are metal, definitive integration with Cubic are deliberated. In pursuit of location

verification system, operators only duty will be driving forklifts and a complete automation

will be provided via the system which will be established in short or medium terms.


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9 DISCUSSIONS, EVALUATIONS AND RESULTS9.1 Discussions

No sooner technology develops, than new implementations on every field of industry

emerges. Nowadays, most mentioned revolution is RFID systems, particularly in logistics.

There is an increasing number of executives who would like to apply RFID systems in

their facilities, not only in the world but also in Turkey. When I was working actively in

the Nexus Informatics Industrywhich is a leader RFID executive and consultant, during

my thesis study, I have witnessed the relish of many executives. However, many of the

firms who would like to apply RFID systems do not know why and how they should apply

the system, and what would be the advantages when they apply. This is the reason of

forgetting the most important element for the RFID systems, planning stage which

provides the return of the investment to the owner within the shortest time and prevents a

failure of the project from the beginning. In order for a RFID system to be successful,

configuration steps which are told in practice should be applied one by one.

As the biggest obstacles preceding RFID systems, there are 3 issues that shines out;

implementation difficulty, standards and cost. Although the borders are removed while

designing a RFID system, increasing cost in the challenging working conditions, required

analysis for the efficiently usage of radio frequencies and long or medium term pilot

studies should be planned before establishing the system.

There is still no world-wide accepted standard exists concerning RFID systems. Each

country determines its own frequency and power emission values. Even though it does not

pose a problem in local implementations, standard space causes serious problems in

international implementations.

Cost factor can be the biggest obstacle preceding the improvement of RFID systems.

Whereas barcode printing is not seen as a cost factor nowadays, passive tags whose usage

is most common are in the price range of 0.15 1.00 USD. Besides, reader and antenna

costs are pretty high when it is compared to barcode systems.

In addition, notions like safety and right to privacy should be regarded.


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9.2 Evaluations and ResultsBesides from its disadvantages, RFID systems also has lots of advantages. As it is

mentioned in the study, tracking in product level, flexible and wide data storage, real-time

multi data transfer are the issues inure to the benefit of the facilities. One of the worlds

leader tire manufacturer and Turkeys leader logistics firm is analysed in the study and

their advantages acquired via RFID systems are seen clearly. High investment costs made

in the beginning are observed to have gainings such as; speed, flexibility, productivity,

abolishment of human factor/automation, customer satisfaction and cost reducement in

time. Also, when the features of RFID sysrem components increase via research and

development, their prices are tended to decrease.

Researches made show that RFID market size which is 5 billion USD nowadays, will

increase approximately 550 % only 10 years later.

Studies still being carried out shows that RFID studies will be an unchangeable notion not

only in industrial issues, but also in our daily lives. In every field we benefit from radio

frequency technology; from passports to credit cards, from cell phones to automobiles.

RFID systems which are seen as a destructive technology on barcode systems as of today,

is only in a structure compatible with barcode systems yet. It is right to tell that barcode

systems will be replaced by RFID systems in near future with reducing the prices of RFID

components, an increase in the number of experts in the system configuration and creating

a specific international standard. Disadvantages which are removed by the highlighted

improvements and with its advantages, it can be considered that RFID systems will be the

most important technology affecting our near future.

When scarcely each one of its two projects is applied in logistics and supply chain

management is considered, it can be said that RFID technology will be a standard in these

fields and the one who applies the active system will succeed.


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INTERNET REFERENCES

Alien Technology

C-Net

ElborgXRF

FEIG Electronics

EPCGlobal International

EPCGlobal Trkiye

GS1 International

GS1 Trkiye

IDTechEx

Intermec

RFID Journal

RFID Solutions

ScienceDirect

TagSYS

burak onurlu (2008), radio frequency identification (rfid) implementations in logistics, ytu,...

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