Sri Lanka Institute of information Technology

BEng(Hons) Electronic Engineering

Industrial Training Report 2011

At

Attotech System Engineering (Pvt.) Ltd

Name : W. R. A. Anuradha Ranasinghe

Student ID : EN10514764 / DEE10m8-3397

Training Period : 3 Months (2011-10-18 to 2012-01-18)

ACKNOWLEDGEMENT

First of all, I would like to express my gratitude to Mr.M. Kalyanapala and Mr. Wijewardane who gave us this opportunity to experience the industrial training and helped us in many ways to complete it

successfully.

Secondly, I would like to thank Mr. Suraj Ladhuhetti who is the Chairman and Managing Director of the Attotech System Engineering (Pvt) Ltd and the General Manager Mr. Roshan Jayamaha

for dedicating their invaluable time to provide us a training period at their company.

Finally I dedicate my sincere gratitude to NAITA for providing an industrial training period for SLIIT engineering students and for their concern about electronic field

ii

ABSTRACT

The following report describes an overview of the types and outcomes of work undertaken by the author

which formed the industrial training component of the Bachelor of Engineering (Electronic Engineering)

degree. In particular, this report examines my involvement in four particular industrial applications and

projects executed by my host company Attotech System Engineering (PVT) Ltd. These four phases will

describe about my personal experience during the training period.

During the period we have been assigned for number of projects under the guidance of a senior officer

to assist them and an individual project to complete by ourselves. All the projects and activities we have

involved are described at the main body. The four major categories are,

• PLC Training and Automation Techniques

• CNC Retrofitting and Machine Tool Automation

• Automated Guided Vehicle and Wi-Fi Communication

• Industrial Automation Components

- Servo Motor Drives

- Variable frequency Drives

- Pneumatics

- Industrial Ink-Jet Printers

Beside what we have experienced in the host company, I have included the details about site visits, self

studying and other stuffs we carried out. That will additionally grant you a better view of this training

period and the basic knowledge that required for a engineering trainee before go to the industry.

In the industry, we have to deal with real world applications and hence we have many constrains, more

stuffs to be analyzed and to be approved. For each phase we involved, I have mentioned the difficulties

and constrains we face during the work carried out. That definitely will help the reader to get an idea

about real world constrains and limitations.

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INTRODUCTION

Engineering technology education is based on industrial ground. Theoretical background is not

sufficient to make a practical engineer, so the industrial training is an essential part of study to make

a technologist technically sound in this field. And it provides us that opportunity to gather practical

knowledge.

SLIIT has recently introduced an industrial training for BEng(Hons) in Electronic Engineering

students to experience the real world engineering activities and constrains. Students have been given

two options.

>> A three months training period after completing the 2nd year and another three months

after completing final year.

>> Or six months training period after completing the final year

Attotech System Engineering (PVT) Ltd

Attotech System Engineering Company is a totally integrated company that provides engineering

solutions for wide variety of industrial applications. And they are one of the leading companies who

deals with SIEMENS industry community in Sri Lanka.

They are providing -

• Machine Tools and Automation Solutions

• CNC machines and Sinumeric Controllers

• RFID solutions

• Siemens PLCs with Totally Automation Solutions

• Automated Guided Vehicles

• Electrical and Pneumatic Components and Solutions

Automation Industry and Technology

Automation is the use of control systems and information technologies to reduce the need for human

work in the production of goods and services. In the scope of industrialization, automation is a step

beyond mechanization. Whereas mechanization provided human operators with machinery to assist

them with the muscular requirements of work, automation greatly decreases the need for human sens-

-ory and mental requirements as well. Automation plays an increasingly important role in the world

economy and in daily experience.

Automation has had a notable impact in a wide range of industries beyondmanufacturing (where it

began). Once-ubiquitous telephone operators have been replaced largely by automated telephone

switch boards and answering machines. Medical processes such as primary screening in electronic

cardiography or radiography and laboratory analysis of human genes, sera, cells, and tissues are carr-

-ied out at much greater speed and accuracy by automated systems. Automated teller machines have

reduced the need for bank visits to obtain cash and carry out transactions. In general, automation has

been responsible for the shift in the world economy from industrial jobs to service jobs in the 20th

and 21st centuries.

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Connections, Local Customers

1. Dankotuwa Porcelain - PLC/ HMI Automation

2. Chevron Lanka Lubricant - PLC/ HMI Automation

3. Caltex Lnka Lubricant - PLC/HMI Automation

4. ID Lanka PVT Ltd - PLC/ Pneumatics/ Packing

5. REX Industries PVT Ltd - CNC Retrofitting

6. Hayleys Group - PLC/ Bottle Packing

Projects and Objectives

My training period can be divided into four phases based on the the technology we used. They are,

• PLC Training and Automation Techniques

Under the control engineering subject at the university, we have learnt the basic concept of PLC, its

programming structure and applications. But this training phase helped us and enhanced our knowledge

about control engineering technique. Since our company had almost all the required resources for PLCs

automation, we learnt A to Z of PLC programming and communication.

• CNC Retrofitting and Machine Tool Automation

Mechanical engineering concepts are essential for every engineering discipline. As the electronic and

Electrical students we do not often deal with Mechanical aspects, but the training period gave me an opp-

-ortunity to get to know about machine tools, machine automation, lathe and milling operations etc. CNC

retrofitting does have all of above aspects. The OKUMA CNC retrofitting project that was given to us

fulfilled my desires about this topic.

• Automated Guided Vehicle and Wi-Fi Communication

Though we learnt some network protocols during the academic year, we have not had a chance to do

practicals with real time routers, modules etc. This phase was really helpful me to learn about Wi-Fi com-

-munication, industrial automated guided vehicles etc. Finally we could complete the project given to us

and details are described below

• Industrial Automation Components

- Servo Motor Drives

- Variable frequency Drives

- Pneumatics

- Industrial Ink-Jet Printers

Finally by compiling this report I would take an opportunity to share my experience, among other

engineering students and with any person who is keen on sharing their practical experiences about

the industrial placement.

“It is not the knowledge make man perfect. Experience makes man

perfect, and it cannot be expressed in words ”

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CONTENT

ACKNOWLEGMENT……………………………………………………ii

ABSTRACT...............................................................................................iii INTRODUCTION……………………………………………………….iv

Programmable Logic Controllers and Automation……………………….1 Project and Activities…………………………………………………………2

SIEMENS Communication Interfaces………………………………………..5 CNC Machine Tools Automation………………………………………………..7

Our Objectives………………………………………………………………...8

Wiring Diagrams……………………………………………………………..11

PCB Manufacturing……………………………………………………….....14

Automated Guided Vehicle and Wi-Fi.................................................................15

Introduction to W-Fi and RCM 4400W...........................................................16

Communication and GUI.................................................................................18

PCB Design and Implementation.....................................................................22

Industrial Automation Components..............................................................…....23

Pneumatics…………………………………………………………………...23

AC Servo Drives……………………………………………………………..25

Variable frequency Drives…………………………………………………...26

Ink-Jet Printers……………………………………………………………….29

Conclusion...……………………………………………………………….…….32

References..............................................................................................................33

Programmable Logical Controllers and Automation Programmable Logical Controllers, commonly known as PLCs are widely used in Automation industry.

Unlike general-purpose computers, the PLC is designed for multiple I/O arrangements extended temperature ranges,

immunity to electrical noise, and resistance to vibration and impact.

Control engineers essentially use PLC to automate their machine tools, for process automation systems etc. There

are several advantages of using PLC rather than go for an micro processor based embedded solu-

-tions.

1. We can control high voltage levels without using additional signal conditioning units.

2. Higher durability for long time process automation system.

3. Easy to program, debug the control system.

4. World wide service support.

Typical PLC network and SIEMENS S7-00 micro PLC

Programming Methods 1. Ladder programming (Easy to use)

2. FBD (Functional Block Diagram programming)

3. STL (Statement List - Bit advance method)

PLC brands 1. Siemens (Largest electronic, electrical company in Europe - Germany)

2. Allan Bradley (Rockwell Automation - USA)

3. GE Fanuc (USA)

4. Schneider (France)

5. Omron PLC

1

Projects and Activities We Involved

• Caltex Modara

This is the first activity we have been given to complete. There is an automated level monitoring system for 5 oil

tanks and previously our company did some maintenance stuffs there. First they had used a black & white HMI to

display the tank levels. Then they changed the HMI panel to colored one and asked our company to program it using

graphic elements.

Hardware & Programming Issue - New HMI unit shows minus values for Tank Levels.

System and Hardware Aspects - Siemens S7-300 PLC (CPU 313C-2 DP)

TP 177B

Communication PROFIBUS DP / PA

DP/PA coupler

Siemens Sitrans LR200

Software - SIMATIC Manager for S7-300

WINCC Flexible for Touch Panel

System Diagram

2

angle of the ultrasonic wave. Sensor has a hand programmer, sends a microwave signal to the tank and

gets the reflected wave back. And calibrate the empty space of a tank.

Measurement range: 0.3m to 20m (1 ft. to 65ft.)

Solution Approach

1. Information Gathering

Fist of all we gathered and refered relevant data sheets and application examples of above hardware

components. Additionally we used Siemens support forum and asked some questions regarding hardware

and software aspects. Our automation engineer gave us an introduction about field communication buses

and communication cables.

2. Site Visit to Caltex Modara

We analyzed the hardware configuration and found no errors. So next step is to go through the PLC

program. We disconnected the MPI bus goes to HMI and connected it to Field PG (Siemens Laptop).

Set the PG/PC interface and configured hardware correctly. Then downloaded the PLC program to PG.

Siemens allows engineers to debug PLC programs while they are connected online. We put the PLC

online and check the values came from sensors. Since we did not have enough time to do it, we take the

program to further analyze.

3. Debug the Error and Fix it

For further reference, our supervisor gave us the HMI program. This was very helpful to identify PLC

memory regions and operations. We checked each data, operational and functional blocks and found the

calculation area of the tank level measurement.

Read the Tank Free Space Level (Sensor Reading) and subtract it from Max Level

This ladder logic network shows where the error has occurred. Sensor reading gives the free space level of the

tank. To take the tank level it should be subtracted from tank max level. Max level is a constant. But here instead

programmer used a data block variable but it’s initial value is always zero. So tank level gives the minus reading of

‘the free space level. So the tank level has a minus value too. Caltex people have these constant values like Max Level,

Max Volume for each tank. We substitute all these constant values for required fields and re uploaded the program to

their PLC. After few calibrations, we could complete our task and finalize the activity.

3

Difficulties we faced -

1. The first day when we visited, we took long time to configure PC to communicate with PLC. So we did not have

a enough time to complete it.

2. Before we visited we had not learnt about S7-300 PLCs. So it was bit difficult to understand PLC program.

• Dankotuwa Porcelain

Dankotuwa porcelain is a leading manufacturer of porcelain tableware. Once they had a failure in their

system and main control unit. All the inputs of the control unit is given using an HMI device. The major issue was a

failure of the HMI. They asked us to come there and fix it as soon as possible since the failure

did a huge manufacturing lost to their production.

That system was there to automate a burning process. That burning process was to paste a designed sticker on

porcelain items. All the heaters, valves, burners and etc have been automated.

Solution Approach

1. Site Visit

We were not given any information about the system. First we went there and their control engineer

described what did happen and he wanted us to fix it as son as possible. Since we did not have a proper

idea about it, first of all we checked the PLC program by downloading it to Field PG. There was no

error in the program and hence we called our supervisor (MD) and informed about the situation. He told

us to check the HMI and to download the HMI program.

Though we had everything we need, unfortunately the HMI was an old siemens first generation

TP27 10” and we did not have the required touch panel software to download the HMI program. When

MD arrived there, he discussed with Dankatuwa staff and brought the HMI to our company,

2. HMI reprogramming

The next day we tried to establish the communication between PC and the HMI. MD gave us the

required software CD “ProTool/ ProSave” and gave a simple introduction about Siemens touch panel

and their history.

After few hours we could communicate with HMI via RS232 cable and reprogrammed HMI

under MD’s instructions. It was really hard to configure the HMI because it’s touch screen sensitivity

is lower due to the improper usage.

Difficulties we faced -

1. Configuring the HMI and bring it to download stage. (due to the less sensitivity)

2. We took long time to find the communication cables for this old touch panel. Siemens has introduced

many communication interfaces and we could learn about those cables and protocols.

4

SIEMENS Communication Cables Interfaces

1. CP 5611 PC card

>> Anti-lightning and anti surge, corresponding to the

Siemens 6 GK1 561-1AA00

>> Photoelectric isolation

>> Desktop computer's PCI slots, to achieve the PROFIBUS DP

/ MPI / PPI communications between PC or PG and the

SIMATIC network

>> Communication rate is 9.6 Kbps ~ 12Mbps.

2. PC-PPI Cable

>> Optoelectronic isolated PC/PPI cable

>> Support 10 bit and 11 bit modem communication

>> Automatically adjust the baud rate from 0 to 115.2Kbps

>> Largest communication distance of up to 2 kilometers.

We used this cable to communicate S7-200 with PC/PG

Most Seiemens products support this cable.

3. MPI Cable

>> Optoelectronic isolated RS232/MPI,Siemens S7-300/400

PLC Programming adapter cable

>> Automatically adjust the communication speed from

19.2Kbps to 115.2Kbps for the PC port

>> Automatically adjust the communication speed from 19.2Kbps

to 187.5Kbps for the MPI interface

Nowadays all kind of touch panels and PLCs have an MPI socket to

Communicate with Field PG or via PC5611 card with PC.

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4. PC-TTY Cable

>> The cable between RS232 and Siemens S5 series PLC programming

interface(DB15),

>> Used for PLC programming software and monitored control system

for S5 series,3 meters.

This cable is used to communicate with SIEMENS 1st generation color

touch panels, like TP-27.

5. PC-RS232 Cable

>> DB 9 mail to female(PC) serial connector cable

>> 9.6 to 115 kBps rate

We used PC-RS232 cables for Simodrive 611V, a server motor driver to

control AC 3phase motors.

6. Cables for SIMATIC LOGO

>> Logo PC cable RS232 optoelectronic isolated programming cable for Siemens

LOGO, 3 meters,can replace Siemens 6ED1 057-1AA00-0BA0

>> Logo USB cable USB optoelectronic isolated programming cable for

Siemens LOGO, 2.5 meters, with communication indicator.

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CNC Lathe and Machine Tool Automation

CNC stands for “Computer Numerical Controller” that refers to the automation of machine tools operated by

abstractly programmed commands encoded on a storage medium. Earlier in 1940, they were introduced as NC (just

numerical controllers) that operated manually using hand wheels, levelers or mechanically automated using Cams

alone. With the development of the PLCs (Programmable Logic Controllers), nowadays automation engineers

integrate PLCs for their machine tool automation.

Earlier manual controller versus newer totally automated controllers

Control Flow of a CNC

There are 4 main elements in the control flow…

1. Human Machine Interface (HMI)

2. Programmable Logic Controller

3. Input Devices (Push Buttons, Limit Switches, Pressure Switches, Sensors etc)

4. Output Devices (Motors, Solenoids, Lamps etc)

Other auxiliary devices:-

1. Contactors, Motor Controllers

2. Relays

3. Distributed IO cards

All these elements connected via common communication protocol. PLC does the communication part among

control devices using their node addresses. Below block diagram shows the control flow of a CNC machine.

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Standard Control Flow of a CNC

Our Objectives….. Our objective was to retrofit two CNC lathe machines, which belong to our company. One lathe machine was barely

wired, but due to a power and maintenance failures, we had to rewire that machine. Using this as a reference, we

should retrofit the second machine which belongs to the REX.

OKUMA LB25 Lathe Machine

This is a 2 axis (X and Z) CNC machine used for lathe works. Originally introduced in Japan year 1990.

These are the specifications of the machine.

Swing Over Bed - 24.41" Dimensions - 159" x 79"

Swing Over Saddle - 18.90" Approximate Weight - 15,300 Lbs.

Z-Axis Travel - 26.3" Controller - SINUMERIC 802D

Maximum Bar Capacity - 3.50" Communication - PROFIBUS DP

Spindle Nose - A2-11

Spindle Hole Diameter - 4.33"

Spindle Speed Range - 52-2800 RPM

Spindle Drive Motor - 30 HP / 20 HP AC

Rapid Traverse Rates (X,Z) - 590 IPM / 787 IPM

Tailstock - #5MT

Tailstock Quill Stroke - 4.72"

8

Auxiliary Input

HMI Output

OKUMA LB25 CNC lathe front view

Block Diagram

We have not been given any wiring diagram or reference. So we had to find and trace each wiring, each device (limit

switches, valves etc) and check them before connecting. And we downloaded the existing PLC program from the

controller to the PC for further reference.

9

Steps we followed:-

1. Being familiar with Lathe machine tools.

Before we enter to the wiring, we needed to identify the mechanical structure and the components of the CNC

which are new to us. Our machine consist of following components

• Two AC 3 phase servo motors for X and Z axis (400V line to line)

• High Power AC Spindle motor (400V line to line)

• Three AC 3 phase motors for Hydraulic, Lubricant and Coolant (200 line to line)

• Turret - Device that consists cutting tools, can be rotated to index the cutting tools

• Chuck - Device used to hold the work piece, clamp it and rotation is done using spindle motor

• Tail Stock - This is used to provide a fixture at the end of the part opposite from the chuck.

• Simodrive 611 - Servo motor drives to control X,Z and Spindle motors

Turret Chuck Tail Stock

3 phase Motors

2. Tracing the Wiring Diagram

Electrical wiring begins from the 3 phase 440 line to line main supply (CEB) connection. In two stages main

supply step downs to 200 V line to line 3 phase, and to 110V single phase using isolation transformers. Complete

wiring diagrams shown below. Entire drawing divided to 4 parts. PLC drives a relay card to supply high voltages

to contactors and lamps.

Due to several reasons like uncertainty, lack of resources and other parallel duties, we took nearly 5 or 6

days to complete the tracing part.

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i) Main power distribution

Symbol Reference -

CB1F - 3 pole main breaker

K4 - Motor contactor of the chip conveyor (24V coil supply)

MCB1 - Miniature Circuit Breaker (isolate 3 phase 400 V)

TR1 - 400/440V to 200V step down transformer for 200V line to line 3 phase motors

TR2 - 200V to 110V step down transformer for 110 contactors

M1 - 3 phase (400V L to L) Chip Conveyor Motor

Chip - PLC output (24 V)

5 - DC ground (0 V)

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ii) Motor Controlling

Symbol Reference -

CB1A - 3 pole 200V L to L isolator

K1 - Spindle Motor Blower Contactor (24V coil supply)

MC1, MC2, MC3 - Motor Contactors and Overload Relay units (200V L to L)

M2 - 3 phase (200V L to L) Spindle Motor Blower

M3 - 3 phase (200V L to L) Coolant Motor

M4 - 3 phase (200V L to L) Hydraulic Motor

M5 - 3 phase (200V L to L) Lubricant Motor

PS2, PS5, PS7 - 110V driven by PLC output using relays

3 - 24V DC supply 5 - DC ground

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iii) Servo Motor Drive Unit and …. iv) 3 phase / 24V DC power unit

Symbol Reference -

MSH1 - 3 pole 400V L to L contactor (110V coil supply)

M6 - 3 phase (400V L to L) Spindle Motor.

M7 - 3 phase (400V L to L) X Axis Servo Motor

M8 - 3 phase (400V L to L) Y Axis Servo Motor

1 - 110V supply

2 - Neutral

3 - 24V DC supply 5 - DC ground

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3. Identify the failures and prepare the PCBs

We found that the main problem has occurred in the relay cards of the control unit. Next step is preparing PCB

and start the wiring. to design a PCB we used ORCAD family software, drew the schematic and create the layout

using layout plus.

Schematic and the PCB Layout

Layout design was sent to “PCB Lanka (Pvt) Ltd” and we created two PCBs for control unit. Then started

the wiring of the machine control unit. An experienced technician helped us to figure the things out, safety

precaution and other steps to be taken.

� In this relay card,

>> An LED is used as an indicator to recognize which relay is activated

>> A diode for the back EMF protection of the relay coil

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Automated Guided Vehicles and Wi-Fi

Introduction to AGV

AGV, automated or automatic guided vehicle is a mobile robot that follows lines, markers or sometimes uses

vision or lasers. Most often they are used in industrial applications to move heavy loads, materials to long distances,

between ware houses.

AGVs increase the efficiency and reduce the time in manufacturing phase and also able to replace the work load

of few employees. The objects can be placed on a set of motorized rollers (conveyor) and then pushed off by reversing

them. Some AGVs use fork lifts to lift objects for storage. AGVs are employed in nearly every industry, including,

pulp, paper, metals, newspaper, and general manufacturing. Transporting materials such as food, linen or medicine in

hospitals is also done.

Navigation Methods

1. Wired - A sensor is attached to the bottom of the robot and is placed facing a conductor wire of radio frequency

carrier signal. Sensor will be induced by the carrier signal and sensor follows the RF signal wire.

2. Guide Tape - Most of the AGVs use this method. This tape can be either a magnetic or a colored one. Using IR

sensor arrays or an inductive sensors, we can navigate robot easily according to the guided tape.

3. Laser Target Navigation/ Wireless

AGV carries a laser transmitter and receiver which the laser is sent off and using reflected

pulse, AGV calculates the distance and the angle of the current position and continuously

upgrade its position to navigate to the target.

Guided Tape AGV Laser Guided AGV

Our Objectives…..

Our company had brought an AGV machine for Research and Development for automation solutions. The

major task was to automate it using a wireless communication system. Since R&D unit already did some projects

using Wi-Fi, as the first step we were given to automate the AGV using Wi-Fi. We have

been given a Wi-Fi communication kit, a microprocessor development board.

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Introduction to Wi-Fi and Rabbit 4400W Module

Wi-Fi is a wireless communication system that allows to connect to a wireless network and to share the data over

the network. In 1985 IEEE formed the 802.11 technology and the protocol and released an ISM band. Normally

Wi-Fi operates in 2.4 GHz range.

Rabbit 4000 processor and 4400 Wi-Fi module were introduced by Rabbit Semiconductor Solutions. They provide

wide variety of embedded solutions for Automation industry and control applications. For our project we used this

embedded Rabbit core and Wi-Fi module as the control board. All of the Rabbit products support “Dynamic C”

programming language.

Beside this package, we were given the Dynamic

C programming CD with sample programs.

Dynamic follows the ISO/ANSI C standard when

feasible and desirable. Because standard does not

take into account the special needs of embedded

systems, it is necessary to depart from the standard in

some areas and desirable in others. The standard does

not take into account important embedded systems

issues such as read only memory and embedded

assembly language.

Work Plan

1. Be Familiar with Dynamic C, Wi-Fi and Rabbit Core Module

Since this communication technology was new to us, we had to learn and prepare about Wi-Fi ourselves.

It was not difficult to adapt for Dynamic C environment because we had learnt C programming stuffs before.

Operating Modes of Wi-Fi 802.11

i Infrastructure Mode

ii Ad-Hoc Mode

Infrastructure Mode

The infrastructure mode requires an access point to manage devices that want to communicate with each

other. An access point is identified with a channel and service set identifier (SSID). Typically, an access

point also acts as a gateway to a wired network, either an Ethernet or WAN (DSL/cable modem). Most

access points can also act as a DHCP server, and provide IP, DNS, and gateway functions. When a device

wants to join an access point, it will typically scan each channel and look for a desired SSID for the access

point.

Once the access point is discovered, the device will logically join the access point and announce itself.

Once joined, the device can transmit and receive data packets much like an Ethernet-based MAC.

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Ad-Hoc Mode

In the ad-hoc mode, each device can set a channel number and an SSID to communicate with. If devices

are operating on the same channel and SSID, they can talk with each other, much like they would on a

wired LAN such as an Ethernet. This works fine for a few devices that are statically configured to talk to

each other, and no access point is needed.

Rabbit Core Module and Dynamic C programming

After configuring the RCM 4400W and the

Rabbit 4000 development board, our next

step was to go through sample programs

and be familiar with C language.

Few sample programs like blink.c and the

toggle.c, we could understand about the

I/O ports of above module. Few network

communication sample programs help us to

get an idea about the communication proto

-cols.

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2. Buildup the Communication and Graphical User Interface

We planed to control the AGV through a Graphical User Interface of a web browser. When the PC or the

laptop runs the browser application, using navigation keys of the interface we can direct the AGV to different

directions.

As the first step we programmed the “BrowseLed.c” file to the Rabbit core module. Then the sample web

interface was used to control the LEDs on the module. Sample web interface has been loaded to the laptop

browser. Successfully we could communicate with the module from the remote laptop under Wi-Fi coverage.

Now to enhance the interface and control the AGV, we had to think and implement a CGI support HTML web

interface, and a control circuit.

CGI enable HTML code :-

#class auto #use "RCM44xxW.lib" #define up 0 #define left 2 #define down 4 #define right 6 #define USERLED 0 #define ON 0 #define OFF 1 #define TCPCONFIG 1 #define _PRIMARY_STATIC_IP "10.10.6.100" #define _PRIMARY_NETMASK "255.255.255.0" #define MY_GATEWAY "10.10.6.1" #define MY_NAMESERVER "10.10.6.1" #define IFC_WIFI_SSID "rabbitTest" #define IFC_WIFI_ROAM_ENABLE 1 #define IFC_WIFI_ROAM_BEACON_MISS 20 #define IFC_WIFI_CHANNEL 1 #define IFC_WIFI_MODE IFPARAM_WIFI_ADHOC #define IFC_WIFI_REGION IFPARAM_WIFI_REGION_AMERICAS #define IFC_WIFI_ENCRYPTION IFPARAM_WIFI_ENCR_NONE #define TCP_BUF_SIZE 2048 #define HTTP_MAXSERVERS 2 #define MAX_TCP_SOCKET_BUFFERS 2 #define REDIRECTTO myurl() #memmap xmem #use "dcrtcp.lib" #use "http.lib" #ximport "pages/browseled.shtml" index_html #ximport "pages/rabbit1.gif" rabbit1_gif #ximport "pages/ledon.gif" ledon_gif #ximport "pages/ledoff.gif" ledoff_gif #ximport "pages/buttonup.gif" buttonup_gif #ximport "pages/buttonleft.gif" buttonleft_gif #ximport "pages/buttondown.gif" buttondown_gif #ximport "pages/buttonright.gif" buttonright_gif #ximport "pages/showsrc.shtml" showsrc_shtml #ximport "browseled.c" browseled_c */ SSPEC_MIMETABLE_START SSPEC_MIME_FUNC( ".shtml", "text/html", shtml_handler), // ssi SSPEC_MIME( ".html", "text/html"), // html 18

SSPEC_MIME( ".cgi", ""), // cgi SSPEC_MIME( ".gif", "image/gif") SSPEC_MIMETABLE_END char led1[15]; char led2[15]; char led3[15]; char led4[15]; char *myurl() { static char URL[64]; char tmpstr[32]; long ipval; ifconfig(IF_DEFAULT, IFG_IPADDR, &ipval, IFS_END); sprintf(URL, "http://%s/index.shtml", inet_ntoa(tmpstr, ipval)); return URL; } int led1toggle(HttpState* state) { if (strcmp(led1,"ledon.gif")==0) strcpy(led1,"ledoff.gif"); else strcpy(led1,"ledon.gif"); cgi_redirectto(state,REDIRECTTO); return 0; } int led2toggle(HttpState* state) { if (strcmp(led2,"ledon.gif")==0) strcpy(led2,"ledoff.gif"); else strcpy(led2,"ledon.gif"); cgi_redirectto(state,REDIRECTTO); return 0; } int led3toggle(HttpState* state) { if (strcmp(led3,"ledon.gif")==0) strcpy(led3,"ledoff.gif"); else strcpy(led3,"ledon.gif"); cgi_redirectto(state,REDIRECTTO); return 0; } int led4toggle(HttpState* state) { if (strcmp(led4,"ledon.gif")==0) strcpy(led4,"ledoff.gif"); else strcpy(led4,"ledon.gif"); cgi_redirectto(state,REDIRECTTO); return 0; } SSPEC_RESOURCETABLE_START SSPEC_RESOURCE_XMEMFILE("/", index_html), SSPEC_RESOURCE_XMEMFILE("/index.shtml", index_html), SSPEC_RESOURCE_XMEMFILE("/showsrc.shtml", showsrc_shtml), 19

SSPEC_RESOURCE_XMEMFILE("/rabbit1.gif", rabbit1_gif), SSPEC_RESOURCE_XMEMFILE("/ledon.gif", ledon_gif), SSPEC_RESOURCE_XMEMFILE("/ledoff.gif", ledoff_gif), SSPEC_RESOURCE_XMEMFILE("/buttonleft.gif", buttonleft_gif), SSPEC_RESOURCE_XMEMFILE("/buttonup.gif", buttonup_gif), SSPEC_RESOURCE_XMEMFILE("/buttondown.gif", buttondown_gif), SSPEC_RESOURCE_XMEMFILE("/buttonright.gif", buttonright_gif), SSPEC_RESOURCE_XMEMFILE("browseled.c", browseled_c), SSPEC_RESOURCE_ROOTVAR("led1", led1, PTR16, "%s"), SSPEC_RESOURCE_ROOTVAR("led2", led2, PTR16, "%s"), SSPEC_RESOURCE_ROOTVAR("led3", led3, PTR16, "%s"), SSPEC_RESOURCE_ROOTVAR("led4", led4, PTR16, "%s"), SSPEC_RESOURCE_FUNCTION("/led1tog.cgi", led1toggle), SSPEC_RESOURCE_FUNCTION("/led2tog.cgi", led2toggle) SSPEC_RESOURCE_FUNCTION("/led3tog.cgi", led3toggle) SSPEC_RESOURCE_FUNCTION("/led4tog.cgi", led4toggle) SSPEC_RESOURCETABLE_END void update_outputs() { /* update O0 */ if (strcmp(led1,"ledon.gif")) BitWrPortI(PADR, &PADRShadow, OFF, up); else BitWrPortI(PADR, &PADRShadow, ON, up); /* update O1 */ if (strcmp(led2,"ledon.gif")) BitWrPortI(PADR, &PADRShadow, OFF, left); else BitWrPortI(PADR, &PADRShadow, ON, left); if (strcmp(led3,"ledon.gif")) BitWrPortI(PADR, &PADRShadow, OFF, down); else BitWrPortI(PADR, &PADRShadow, ON, down); if (strcmp(led4,"ledon.gif")) BitWrPortI(PADR, &PADRShadow, OFF, right); else BitWrPortI(PADR, &PADRShadow, ON, right); } main() {

brdInit(); strcpy(led1,"ledoff.gif"); strcpy(led2,"ledoff.gif"); strcpy(led3,"ledoff.gif"); strcpy(led4,"ledoff.gif"); sock_init_or_exit(1); http_init(); tcp_reserveport(80); while (1) { update_outputs(); http_handler(); } }

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This code helps to functionalize this 4 navigation buttons, that when you press a button, that data will be sent to the Wi-Fi

module through wireless data packets and that will pull 3.3V

CMOS level voltage in deferent output ports. (say if we press

UP button, port A pin 1 will be high at the moment, and will

be low when pressed again)

This image shows the IP configuration of the Laptop. Our network

address is 10.10.6.0 and we used Ad-Hoc method for communication.

3. Control Circuit and AGV

Our AGV has a one main motor to rotate the axial and this is used to move the vehicle forward and reverse.

Additionally it has a steering handle that can be controlled using a motor and some mechanical components.

By rotating the handle, we can manually steer the vehicle instead. However for the handle manufacture company

does not give a motor. So our main primary objective was just to move the AGV forward and reverse.

To achieve the task we designed a transistor based relay drive circuit that can control 24V AGV motor using 3.3

V CMOS logic. Control block diagram, AGV and designed circuit are shown above.

AGV which is able to lift 600 kg

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>> When a button pressed in web GUI, the relevant pin

of the module set to 3.3V.

>> That CMOS voltage is supplied to transistors related to

S1 & S4 or S2 & S3 simultaneously.

>> Those transistors drive S1 & S3 or S2 & S4 respectively

>> This will change the direction of the front weel

>> The circuit is called relay hybrid drive circuit

PCB design and Implementation

This is the final step of our project. To design a PCB, we used “PCB Wizard” software and all the

fabrication stuffs done by us. We bought required electronic components, not the Relays since they were

available at company’s stores.

Components - 2 Drive Transistors D400 (For max coil current-

70mA of relays)

2 Relays (Omron 24V DC / 10A max)

2 Diodes (1N4001)

3/4 plastic connectors

16 pin male header

Circuit Wire

Testing and Difficulties We Faced

We could control and complete our AGV project successfully. We tested it for 3 times and analyze the system

parameters of it (Current for different loads, Frictional impact to the wheel etc.) You can refer the testing and

the performance of the AGV here.

http://www.youtube.com/watch?v=77CNzZqCDBw

Difficulties :-

• There are less online resources, examples available for Rabbit core module to get an idea about

the project.

• When testing the AGV, the Relay components were burnt due to the higher current.

• We had to wait several days due to lack of resources.

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Industrial Automation Components Beside above applications, the automation industry consists of few more auxiliary devices like

Pneumatics, Motor Drives, VFDs and Industrial Printers etc. Lets discuss about those devices and

their appliances.

1. Pneumatics

Pneumatics is a branch of technology that deals with the study and application of pressurized gas to

effect mechanical motion. Pneumatic systems are extensively used in industry, where factories are comm-

-only plumbed with compressed air or compressed inert gases because a centrally located and electrically powered

compressor that powers cylinders and other pneumatic devices through solenoid valves is often

able to provide motive power in a cheaper, safer, more flexible, and more reliable way than a large number of electric

motors and actuators. Pneumatics also has applications in dentistry, construction mining, and other areas.

Attotech System Engineering Company provides pneumatic solution for various industrial applications

and they have approximately 15 million worth pneumatic stock. Fortunately we had a chance to learn about

this field which is not covered in our degree program.

Pneumatic Products can be divided into 4 categories

i) Air Combination

This system called FRL consist 3 stages. All three combinations are required for a proper operation.

Those are,

� Filter - Used to remove contaminants that can damage to the component. Filters can be added to

where,

i at the intake of the compressor that takes outside air

ii at the outlet of the compressor

iii at the input of some pneumatic driven machines

� Regulator - Adjust the pressure level to desired level and maintain a constant pressure level

When the sir supply pressure is too high for pneumatic components, we can control

it using the level knob.

� Lubricant - Many components in a pneumatic system are lubricated, specially moving parts !

So that helps to reduce the friction between the surfaces of those parts.

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ii) Control Equipment

A solenoid valve is an electromechanical valve for use with liquid or gas. The valve is controlled by an electric current

through a solenoid, (typically 24V) in the case of a two-port valve the flow is switched

on or off, in the case of a three-port valve, the outflow is switched between the two outlet ports. Multiple solenoid

valves can be placed together on a manifold. Solenoid valves are the most frequently used control elements in fluidics.

Their tasks are to shut off, release, dose, distribute or mix fluids. Solenoids offer fast and safe switching, high

reliability, long service life, good medium compatibility of the materials used, low control power and compact design.

iii) Execute Equipment

Pneumatic cylinders (air cylinders) are mechanical devices which use the power of compressed gas to produce a force

in a reciprocating linear motion. Like hydraulic cylinders, pneumatic cylinders use the stored potential energy of a

fluid, in this case compressed air, and convert it into kinetic energy as the air expands in an attempt to reach

atmospheric pressure. This air expansion forces a piston to move in the desired direction. The piston is a disc or

cylinder, and the piston rod transfers the force it develops to the object to be moved. Engineers prefer to use

pneumatics sometime because they are quieter, cleaner, and do not require large amounts or space for fluid storage.

iv) Pneumatic fittings

These powerful diverse ranges of pneumatic fittings are easily fitted for any

system. This kind of items use for instant tubing connection, controlling the operation

speed of a driving device, turning air pressure on and off for pneumatic devices and

controlling air pressure and discharging the residual pressure. We can find various types

of fittings. They are one touch fitting, speed controller, hand valve, hand slide valve and

check valve.

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2. Motor Drivers and VFDs

Motor is the heart of Electrical industry. Even in the Automation, Mechanical and Control engineering industries,

motors do the significant part of the process. Hence the motor controlling is an essential task to be done in every

application. As the electronic undergraduate students we have deal with electronic servo motors in robotic

applications. But when we come to the industry, the motor controlling takes place in 3 phase generation, CNC

machines etc. Here I am going to describe about AC servo motor drivers and Variable Frequency Drivers.

AC Servo Motor Drivers

SIMODRIVE 611 U

Simodrive 611U is a SIEMENS product which can be universally used in the modular SIMODRIVE 611

converter system as a result of its communication interfaces, the motors and encoder systems and option

modules which can be used. Two independent drive controls are implemented on a 2–axis board.The closed

–loop drive controls can be operated in the following operating modes with motor frequencies up to 1400 Hz:.

Motors can be used :

> 1FK6, 1FT6 servomotors up to 140 Nm

> 1FE1 permanent–magnet synchronous motors

> 1PH induction motors up to 100 kW (1PH6, 1PH4, 1PH2, 1PH7)

> Induction motors without encoder

> Standard 1LA induction motors up to 100 kW

Each drive has 2 modules, Infeed Module and Power Module. Wiring diagram has been included in CNC part.

To program the servo drive, SIEMENS provides “Simocom U” software and the communication is done via

RS232 protocol. This driver can also be parameterized using LCD and interface buttons on it.

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Handling Exceptions

The segment display is automatically changed over into the alarm mode when one or several faults or warnings

occur. The faults and warnings are output flashing on the display unit. They can be displayed as follows.

When the fault will occur it will show on display as above example. We faced such kind of situation, when

we power on the SIMODRIV to control the motor. And we could come up with that problem by following

the instructions in user manual according the error number.

Error007 (Error when initializing Supplementary info: \%X)

An error occurred when loading the firmware from the memory module. Cause: Data transfer

error, FEPROM memory cell defective Supplementary information: only for Siemens internal

error diagnostics.

Variable Frequency Drivers

VFD is just one part of a process but the entire process may be depending on that VFD. It is used for controlling

the rotational speed of an alternating current(AC) electric motor by controlling the frequency of the electrical

power supplied to the motor. A variable frequency drive is a specific type of adjustable-speed drive. Variable

frequency drives are also known as adjustable-frequency drives (AFD), variable-speed drives (VSD), AC drives,

micro drives or inverter drives.

Variable-frequency drives are used in a wide number of applications to control pumps, fans, hoists, conveyors,

and other machinery.

Benefits :-

1. Energy Saving

AC motor-driven applications that do not require full speed, can save energy by controlling the motor

with a variable speed drive. Energy cost saving with variable torque can be significant, often paying for

the cost of VFD within a matter of months. In variable torque applications such as fans and blowers, the

torque required varies roughly with the square of the speed, and the horsepower required varies roughly

with the cube of the speed, resulting in a large reduction of horsepower for even a small reduction in

speed. The motor will consume only 25% as much power at 63% speed than it will at 100% speed

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2. Starting torque control

Across-the-line single-speed starters start motors abruptly, subjecting the motor to a high starting torque

and to current surges that are up to 8 times the full-load current. Variable speed drives instead gradually ramp

the motor up to operating speed to lessen mechanical and electrical stress, reducing maintenance and repair

costs, and extending the life of the motor and the driven equipment. Reduced voltage starting methods

also accelerate a motor gradually, but VF drives can be programmed to ramp up the motor much more

gradually and smoothly, and can operate the motor at less than full speed to decrease wear and tear.

Siemens Micro Master 420 VFD

Typical installation for Single and Three Phase Connection

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Operation

1. Rectifier Stage

The 3-phase AC voltage goes into the rectifier section which is

made up of a group of gated diodes. In most VFDs, these diodes

are in a group of 6 as diagramed above. One VFD manufacturer

has stressed that there should be more sets of diodes, 12, 18, even

24. Diodes (D1 through D6) allow current to flow only in one

direction when enabled by the gate signal.

In this diagram, the AC power on L1 goes into Diodes D1 and

D2. Because of the position of these diodes, current flow can only

go up. The D1 diode conducts when the AC is positive and D2

conducts when the AC goes negative. This drives the top line (+) more positive and the bottom line (-) more

negative. Diodes D3 and D4 convert L2 power to DC and Diodes D5 and D6 convert L3. A volt ohmmeter or

VOM can be used to measure this DC voltage. In this type of circuit, the DC voltage is 1.35 times the AC line

voltage.

If 240 Vac is coming in, 324 Vdc is generated.

2. Intermediate Circuit (DC Link)

The Intermediate Circuit also known as a DC Link, can be seen

as a power storage facility for the next section, the inverter section.

There are 2 major components to the DC Link section, capacitors

and coils.

In the diagram above only one capacitor is shown but it is always

a series of capacitors. With Danfoss VFDs, this intermediate section

always uses DC coils also known as DC Line Reactors or DC chokes.

3. Inverter

The next part of the VFD is the Inverter section. This section takes

the DC voltage from the intermediate section and, with the help of

the control section, fires each set of IGBT (Insulated Gate Bipolar

Transistors) to the U, V and W terminals of the motor. This firing of

the IGBTs is known as Pulse Width Modulation (PWM) and is

described in the next couple of slides.

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These transistors switch the input signal, as the length of time is

increased for the IGBT to be ON and then OFF, the motor

responds to it as a sinusoidal waveform. The positive IGBT fires

first in the diagram followed by its negative counterpart. Only one

motor terminal (U) is shown but the same type of activity would

appear on V and W. This modulation is called pulse width

modulation.

4. Control & Regulation Section

The control section coordinates and regulates signals

inside the drive. This is where numerous calculations

are completed to properly switch the IGBTs.

This control section uses Vector technology, which

separates the torque producing current from the

magnetizing current. In the diagram above the current

going to the AC motor is being monitored.

Industrial Ink-Jet Printers

All of us at least once in our life have seen, worked with Printers. Ink-Jet, Dot-Matrix, Laser printers are widely

used in many applications. During our training period we learnt about Ink-Jet printers used for industrial application.

Mainly production and manufacturing companies use them for product marking and labeling their brand names,

technical data etc.

>> What is industrial inkjet printing?

Industrial inkjet printing essentially means using inkjet technology as a printing or deposition process

in manufacturing or on production lines. While all inkjet technologies can fundamentally be described as the

digitally controlled ejection of drops of fluid from a print head onto a substrate.

>> Industrial inkjet technology

Industrial inkjet printing systems, industrial inkjet print heads they are based on, broadly classified

as either continuous (CIJ) or drop on demand (DOD), with variants within each classification.

-- Continuous Inkjet Printing (CIJ)

Continuous inkjet printing is primarily used for coding and marking of products and packages.

In this technology, a pump directs fluid from a reservoir to one or more small nozzles, which eject

a continuous stream of drops at high frequency (in the range of roughly 50 kHz to 175 kHz) using

a vibrating piezoelectric crystal. The drops pass through a set of electrodes which impart a charge

onto each drop. The charged drops then pass a deflection plate which uses an electrostatic field to

select drops that are to be printed and drops to be collected and returned for reuse.

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--Drop on Demand Inkjet Printing (DOD)?

Drop on demand is a broad classification of inkjet printing technology where drops are ejected

from the print head only when required. In general, the drops are formed by the creation of a pressure

pulse within the print head. The particular method used to generate this pressure pulse creates the

primary subcategories within DOD, namely thermal and Piezo.

LEIBINGER JET 3 industrial printer

Attotech System Engineering provides continuous inkjet printers like LEIBINGER JET 3 and

technical components, service for any kind of printers industrial labeling systems for non-contact

food and product labeling in all industries. The industrial inkjet printers code and mark products,

packagings and food with data matrix codes, bar codes, lot numbers, etc. with various inks. They

are equipped with the LEIBINGER automatic nozzle seal to prevent a drying of ink..

Printer with Print Head

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Specifications:

� Printing speed Up to 6,6 m/s (10 cpi)

� Ink colors: Black, yellow, red, orange, white, blue, green

� Environmental conditions and Supplies

* 100 V-240 V, 50-60 Hz, max. 40 VA

* Temperature range +5 °C to +45°C

* Relative humidity max. 90% non condensing

* No external supply of compressed air is required

* Cabinet according to class IP 54

� Amount drops: 32 Drops

Managing Director asked us to repair few of those printers that had a block in ink flow of the Suction

Pumps. In order to repair the printer first we cleaned all the ink carrying tubes by using solvent. The

problem has occurred inside the suction filter and the pump.

There was a ink flowing disturbances at the suction filter out put tube and after cleaning that we could

solve the ink flowing jam problem. As well as we have encountered another problem at the print head.

So we cleaned the drop generator unit to make the drop production process properly.

.

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Conclusion

The opportunity to work at Attotech System Engineering provided me a chance to experience

A variety types of engineering projects and applications. Further that opportunity allowed us

to recognize the engineering requirements in Sri Lanka and how to work as a problem solver

in the industry.

This Training Period benefits us....

1. PLC programming and Automation

2. CNC Training and Machine Tools Automation

3. Wi-Fi Communication and AGVs

4. Industrial Automation Devices and Tools like Servo Drives, VFDs etc.

5. Finally a great working experience in many fields

As an apprentice who has been enlisted under NAITA, I hope to complete my next training

program after completing my final year.

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References…….

1. VFD 101 Lessons 3 - Concepts and Basic (EE1- 2009)

http://www.danfoss.com/NR/rdonlyres/B07BD285-5895-48C9-AB04-2B0FBED854F6/0/vfdlesson3.pdf

2. Siemens Automation Support Forum

http://www.automation.siemens.com/WW/forum

3. Siemens, Kyocera Catalogs at Attotech System Engineering (Pvt) Ltd

4. SIMODRIVE 611U Functional Manual and Configure Manual (05/2008 Edition)

http://www.automation.siemens.com/doconweb/content.asp?cd=sinumerik_simodrive_611U

5. Machine Tool Tutorial

http://www.machinetools.com/us/listings/group/1023

6. SINUMERIC 802D Controller Manual (V01.06.00 /20.09.2004)

http://www.automation.siemens.com/doconweb/content.asp?cd=sinumerik_802D

7. Rabbit 4400W Wi-Fi OEM User Manual (019–0160 • 080131–F)

ftp://ftp1.digi.com/support/documentation/0190160_g.pdf

8 Micromaster 420 Variable frequency Drive(V1.1)

www.acpd.co.uk/sei/s/1488/f199.pdf

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