integration of electronic speed governor with rfid technology for speed limiting

ABSTRACT

The main aim of this project is to present a conceptual model of a microprocessor based

variable electronic speed governor that can be implemented to control the speed of any

vehicle depending on the local speed limit. The circuit is cost effective, efficient and easy

to implement on already existing vehicles. Every city, town or a village, can be marked and

divided into individual zones. The division depends upon the area under which the

business, residential, and industrial regions come. The central business district being a very

busy traffic zone demands the least speed limit, with the residential and industrial zones

having lesser traffic densities, the speed limits will vary accordingly.

Any city or town can be divided into physical zones which are classified according to

different speed ranges. A transmitter is placed at all exit and entry points of the interface of

any two zones that transmits a message signal at carrier frequency, indicating the upper

limit value of the zones speed range into which the vehicle is entering at that moment, to

the receiver which gives the message as an input to a preprogrammed ARM 7

Microprocessor embedded within the automobile which compares the speed of the vehicle

measured by a sensor at the maximum allowable speed and automatically regulates the

speed of the vehicle. The speed of the vehicle can be varied by varying the duty cycle of

the pulse input. The entire system is a low cost variable electronic speed governor, small in

size and easy to assemble onto an existing vehicle without disturbing its present

arrangement.

The output of project would be that speed of vehicle is reduced by 25% in zone1 and 50%

in zone 2.

Chapter-1

OVERVIEW OF THE PROJECT

The main aim of this project is to present a conceptual model of a microprocessor based

variable electronic speed governor that can be implemented to control the speed of any

vehicle depending on the local speed limit. The circuit is cost effective, efficient and easy

to implement on already existing vehicles.

The entire project is divided into three sections:

1. Input section

2. Control section

3. Output section

Input section:

The input section consists of aRFID module and non-contact type tachometer. This

Tachometer uses Non-contact IR Tachometer for measuring the speed of the shaft. This

circuit sends signal HIGH or LOW pulses to the processor.

Processing section:

In this section we use arm 7 microprocessor for processing the input. We have three

separate programs each for zone detection,speed calculation, speed display on LCD, error

detection and error correction via servo motor.

Output section:

The output is given to change the throttle valve position. This is done with the help

of a servo motor which is in turn connected to the valve. The arm7 calculates the error and

sends the appropriate error correction signal to the servo motor. Then the servo motor

rotates and in turn rotates the throttle valve thereby gear transmission system.

Fig 1.1BLOCK DIAGRAM OF THE PROJECT

1.1 Components used in the project:

1.ARM 7 micro processor

2.ATMEGA 8 micro controller

3.16x2 LCD display

4.RF Receiver and Transmitter

5.Variable DC motors

6.12v DC power supply

7.L293d motor driver IC

Chapter -2

LITERATURE REVIEW

The development of project was started with background study or literature review about

other system that related to road safety. This is done by find out the journal, articles and

books that relate with this project.Here are some previously used technologies related to

road safety.

Firstly most School Zone signs should have flashing lights, especially in hot zones, can

have these flashing lights as well because some drivers do not pay attention if there are no

flashing lights. The speed limit in hot zones should be reduced, especially if they keep

occurring so reducing the speed limit from 60km to 50km or even 40km if need be can be

an option.

Secondly, more sensory input needs to occur to get drivers attention like a loud warning

bell or beeping noise and a loud recorded voice on speakers before entering a certain area

or hot zone, for example You are about to enter a hot zone, please reduce speed

immediately, maintain control of the vehicle and secure seat belts.

Thirdly, more speed humps in certain areas and hot zones. This works well in general, and

for those who disobey the speed humps, it can be annoying and cause possible damage to a

car.

After understood all the related concepts, innovation of previous system is designed. Then,

the circuit of zone section and vehicle is designed. After all the designing process is done,

the circuit design is tested on test board.. After the test is satisfied, the circuit is fabricated.

Lastly, the prototype is tested and measured.

Chapter-3

ARM PROCESSOR

3.1 ARM Processor

ARM stands for Advanced RISC Machines. It is a 32 bit processor core, used for high end

application. It is widely used in Advanced Robotic Applications.

Fig: 3.1ARM Processor

3.1.1 History and Development

ARM was developed atAcron Computers ltd of Cambridge, England between 1983 and

1985.

RISC concept was introduced in 1980 at Stanford and Berkley.

ARM ltd was found in 1990.

ARM cores are licensed to partners so as to develop and fabricate new microcontrollers

around same processor cores.

3.1.2 Key Features

1. 16-bit/32-bit ARM7TDMI-S microcontroller in a tiny LQFP64 package.

2. 8 Kb to 40 Kb of on-chip static RAM and 32 Kb to 512 Kb of on-chip flash memory.

128-bit wide interface/accelerator enables high-speed 60 MHz operation.

3. In-System Programming/In-Application Programming (ISP/IAP) via on-chip boot loader

software. Single flash sector or full chip erase in 400 ms and programming of 256 bytes in

1 ms

4. Embedded ICERT and Embedded Trace interfaces offer real-time debugging with the on-

chip Real Monitor software and high-speed tracing of instruction execution.

5. USB 2.0 Full-speed compliant device controller with 2 Kb of endpoint RAM.

In addition, the LPC2146/48 provides 8 Kb of on-chip RAM accessible to USB by DMA.

6. One or two (LPC2141/42 vs. LPC2144/46/48) 10-bit ADCs provide a total of 6/14

Analog inputs, with conversion times as low as 2.44 s per channel.

7. Single 10-bit DAC provides variable analog output (LPC2142/44/46/48 only).

8. Two 32-bit timers/external event counters (with four capture and four compare channels

each), PWM unit (six outputs) and watchdog.

9. Low power Real-Time Clock (RTC) with independent power and 32 kHz clock input.

10. Multiple serial interfaces including two UARTs (16C550), two Fast I2C-bus (400 Kbit/s),

SPI and SSP with buffering and variable data length capabilities.

11. Vectored Interrupt Controller (VIC) with configurable priorities and vector addresses.

12. Up to 45 of 5 V tolerant fast general purpose I/O pins in a tiny LQFP64 package.

13. Up to 21 external interrupt pins available.

14. 60 MHz maximum CPU clock available from programmable on-chip PLL with settling

time of 100 s.

15. On-chip integrated oscillator operates with an external crystal from 1 MHz to 25 MHz.

Fig: 3.2 LPC2144/46/48 pinning

Fig: 3.3 Block diagram of ARM 7

3.1.3Architectute

3.1.3.1 Core Data path

Architecture is characterized by Data path and control path.

Data path is organized in such a way that, operands are not fetched directly from memory

locations. Data items are placed in register files. No data processing takes place in memory

locations.

Instructions typically use 3 registers. 2 source registers and 1 destination register.

Barrel Shifter preprocesses data, before it enters ALU.

Barrel Shifter is basically a combinational logic circuit, which can shift data to left or right

by arbitrary number of position in same cycle.

Increment or Decrement logic can update register content for sequential access.

3.1.3.2 Pipeline

In ARM 7, a 3 stage pipeline is used. A 3 stage pipeline is the simplest form of pipeline

that does not suffer from the problems such as read before write.

In a pipeline, when one instruction is executed, second instruction is decoded and third

instruction will be fetched.

This is executed in a single cycle.

3.1.3.3 Register Bank

ARM 7 uses load and store Architecture.

Data has to be moved from memory location to a central set of registers.

Data processing is done and is stored back into memory.

Register bank contains, general purpose registers to hold either data or address.

It is a bank of 16 user registers R0-R15 and 2 status registers.

Each of these registers is 32 bit wide.

3.1.3.4 Data Registers- R0-R15

R0-R12 - General purpose registers

R13-R15 - Special function registers of which,

R13 - Stack Pointer, refers to entry pointer of Stack.

R14 - Link register, return address is put to this when ever a subroutine is called.

R15 - Program counter

Depending upon application R13 and R14 can also be used as GPR. But not commonly

used.

Fig: 3.4 Data Registers- R0-R15

In addition there are 2 status registers

CPSR - Current program status register, status of current execution is stored. CPSR

contains a number of flags which report and control the operation of ARM7 CPU.

SPSR - Saved program status register, includes status of program as well as processor.

3.1.3.5 Vectored Interrupt Controller

The Vectored interrupt controller takes 32 interrupt request inputs and

programmable assigns them into 3 categories, FIQ, vectored IRQ, and non-vectored IRQ.

The programmable assignment scheme means that priorities of interrupts from the various

peripherals can be dynamically assigned and adjusted.

3.1.3.6 Features

1. ARM Prime cell vectored interrupt controller

2. 32 interrupt request inputs

3. 16 vectored IRQ interrupts

4. 16 priority levels dynamically assigned to interrupt requests

5. Software interrupt generation.

3.1.3.7 Description

1. Fast Interrupt request have the highest priority. If more than one request is assigned to FIQ,

the VIC ORs the requests to produce the FIQ signal to the ARM processor.

2. The fastest possible FIQ latency is achieved when only one request is classified as FIQ,

because then the FIQ service routine can simply start dealing with that device.

3. But if more than one request is assigned to the FIQ class, the FIQ service routine can read

a word from the VIC that identifies which FIQ source(s) is (are) requesting an interrupt.

4. Vectored IRQs have the middle priority, but only 16 of the 32 requests can be assigned to

this category.

5. Any of the 32 requests can be assigned to any of the 16 vectored IRQ slots, among which

slot 0 has the highest priority and slot 15 has the lowest.

6. Non-vectored IRQs have the lowest priority.

7. The victors the requests from all the vectored and non-vectored IRQs to produce the

i. IRQ signal to the ARM processor. The IRQ service routine can start by reading a register

from the VIC and jumping there. If any of the vectored IRQs are requesting, the VIC

provides the address of the highest-priority requesting IRQs service routine, otherwise it

ii. Provides the address of a default routine that is shared by all the non-vectored IRQs.

8. The default routine can read another VIC register to see what IRQs are active.

9. All registers in the VIC are word registers. Byte and halfword reads and write are not

supported.

10. Additional information on the Vectored Interrupt Controller is available in the ARM

i. PrimeCell Vectored Interrupt Controller (PL190) documentation.

3.2. ARM 7 LPC 2148 DEVELOPMENT BOARD

Fig:3.5. Arm 7 LPC 2148 development board

Increasingly, embedded systems developers and system-on-chip designers select specific

microprocessor cores and a family of tools, libraries, and off-the-shelf components to

quickly develop new microprocessor-based products and applications. ARM is one of the

major options available for embedded system developer.

Over the last few years, the ARM architecture has become the most pervasive 32-bit

architecture in the world, with wide range of ICs available from various IC

manufacturers. ARM processors are embedded in products ranging from cell/mobile

phones to automotive braking systems. A worldwide community of ARM partners and

third-party vendors has developed among semiconductor and product design companies,

including hardware engineers, system designers, and software developers.

ARM7 is one of the widely used micro-controller family in embedded system application.

This section is humble effort for explaining basic features of ARM-7.

ARM is a family of instruction set architectures for computer processors based on a

reduced instruction set computing (RISC) architecture developed by British company

ARM Holdings.

A RISC-based computer design approach means ARM processors require significantly

fewer transistors than typical processors in average computers. This approach reduces

costs, heat and power use. These are desirable traits for light, portable, battery-powered

devicesincluding smartphones, laptops, tablet and notepad computers), and

other embedded systems. A simpler design facilitates more efficient multi-core CPUs and

higher core counts at lower cost, providing higher processing power and improved energy

efficiency for servers and supercomputers.

STARTING WITH LPC2148

LPC2148 is the widely used IC from ARM-7 family. It is manufactured by Philips and it

is pre-loaded with many inbuilt peripherals making it more efficient and a reliable option

for the beginners as well as high end application developer.

8 to 40 kB of on-chip static RAM and 32 to 512 kB of on-chip flash program

memory.128 bit wide interface/accelerator enables high speed 60 MHz operation.

In-System/In-Application Programming (ISP/IAP) via on-chip boot-loader software.

Single flash sector or full chip erase in 400 ms and programming of 256 bytes in 1ms.

Embedded ICE RT and Embedded Trace interfaces offer real-time debugging with the

on-chip Real Monitor software and high speed tracing of instruction execution.

USB 2.0 Full Speed compliant Device Controller with 2 kB of endpoint RAM. In

addition, the LPC2146/8 provides 8 kB of on-chip RAM accessible to USB by DMA.

One or two (LPC2141/2 vs. LPC2144/6/8) 10-bit A/D converters provide a total of

6/14analog inputs, with conversion times as low as 2.44 us per channel.

Single 10-bit D/A converter provides variable analog output.

Two 32-bit timers/external event counters (with four capture and four compare channels

each), PWM unit (six outputs) and watchdog.

Low power real-time clock with independent power and dedicated 32 kHz clock input.

Multiple serial interfaces including two UARTs (16C550), two Fast I2C-bus(400 kbit/s),

SPI and SSP with buffering and variable data length capabilities.

Vectored interrupt controller with configurable priorities and vector addresses.

Up to 45 of 5 V tolerant fast general purpose I/O pins in a tiny LQFP64 package.

Up to nine edge or level sensitive external interrupt pins available.

On-chip integrated oscillator operates with an external crystal in range from 1 MHz to30

MHz and with an external oscillator up to 50 MHz.

Power saving modes include Idle and Power-down.

Individual enable/disable of peripheral functions as well as peripheral clock scaling for

additional power optimization.

Processor wake-up from Power-down mode via external interrupt, USB, Brown-Out

Detect (BOD) or Real-Time Clock (RTC).

FIRST STEP- HARDWARE REQUIREMENT

Here is the pin configuration of LPC 2148.

Now let us start with the hardware requirement of LPC2148.

LPC2148 need minimum below listed hardware to work properly.

1. Power Supply

2. Crystal Oscillator

3. Reset Circuit

4. RTC crystal oscillator

5. UART

1. Power Supply

LPC2148 works on 3.3 V power supply. LM 117 can be used for generating 3.3 V supply.

However, basic peripherals like LCD, ULN 2003 (Motor Driver IC) etc. works on 5V. So

AC mains supply is converted into 5V using below mentioned circuit and after that LM

117 is used to convert 5V into 3.3V.

Transformer:It is used to step down 230V AC to 9V AC supply and provides isolation

between power grids and circuit.

Rectifier: It is used to convert AC supply into DC.

Filter:It is used to reduce ripple factor of DC output available from rectifier end.

Regulator:It is used to regulate DC supply output.

Circuit for this is as shown below.

Here, Regulator IC 7805 is used to provide fix 5V dc supply. Now we can use LM 117 for

generating 3.3V supply from 5V using below circuit.

2. Reset Circuit

Reset button is essential in a system to avoid programming pitfalls and sometimes to

manually bring back the system to the initialization mode. Circuit diagram for reset is as

shown below. MCP 130T is a special IC used for providing stable RESET signal to LPC

2148.

3. Oscillator Circuit

Oscillations, the heartbeat, are provided using a crystal and are necessary for the system to

work.

The value of capacitors C20 & C21 depends upon the frequency of crystal Y3. General

circuit and its equivalent circuit is as shown below.

We can also use external oscillator for providing system clock. Circuit for this application

is as given below.

4. RTC Oscillator Circuit

It provides clock for RTC operation.

5. UART

LPC 2148 has inbuilt ISP which means we can program it within the system using serial

communication on COM0. It has also COM1 for serial communication. MAX 232/233 IC

must be used for voltage logic conversion. Related connections are as given below.

A Universal asynchronous receiver/transmitter, abbreviated UART is a piece of

computer hardware that translates data between parallel and serial forms. The universal

designation indicates that the data format and transmission speeds are configurable. The

electric signalling levels and methods (such as differential signalling etc.) are handled by a

driver circuit external to the UART. A UART is usually an individual (or part of an)

integrated circuit used for serial communications over a computer or peripheral device

serial port. UARTs are now commonly included in microcontrollers.

3.2.1 Universal Asynchronous Receiver/Transmitter 0

Features

16 byte receive and transmit FIFOs

Register locations conform to 550 industry standard

Receiver FIFO trigger points at 1, 4, 8, and 14 bytes

Built-in fractional baud rate generator with auto bauding capabilities.

Mechanism that enables software and hardware flow control implementation

3.2.2 Universal Asynchronous Receiver/Transmitter 1

Features

UART1 is identical to UART0, with the addition of a modem interface.

16 byte receive and transmit FIFOs

Register locations conform to 550 industry standard

Receiver FIFO trigger points at 1, 4, 8, and 14 bytes

Built-in fractional baud rate generator with auto building capabilities.

Mechanism that enables software and hardware flow control implementation

Standard modem interface signals included with flow control (auto-CTS/RTS) fully

supported in hardware (LPC2144/6/8 only).

3.3 Analog-To-Digital Converter (ADC)

Basic clocking for the A/D converters is provided by the VPB clock. A

programmable divider is included in each converter, to scale this clock to the 4.5 MHz

(max) clock needed by the successive approximation process.

Features

10 bit successive approximation analog to digital converter (one in LPC2141/2 and two in

LPC2144/6/8).

Input multiplexing among 6 or 8 pins (ADC0 and ADC1).

Power-down mode.

Burst conversion mode for single or multiple inputs.

Optional conversion on transition on input pin or Timer Match signal.

Global Start command for both converters (LPC2144/6/8 only).

3.3.1 Operation

3.3.1.1 Hardware-Triggered Conversion

If the BURST bit in the ADCR is 0 and the START field contains 010-111, the

ADC will start a conversion when a transition occurs on a selected pin or timer match

signal. The choices include conversion on a specified edge of any of 4 Match signals, or

conversion on a specified edge of either of 2 Capture/Match pins. The pin state from the

selected pad or the selected Match signal, XO Red with ADCR bit 27, is used in the edge

detection logic.

3.3.1.2 Real Time Clock

Features

Measures the passage of time to maintain a calendar and clock.

Ultra Low Power design to support battery powered systems

Provides seconds, minutes, hours, day of month, month, year, day of week, and day of year

Dedicated 32 kHz oscillator or programmable prescaler from VPB clock.

Dedicated power supply pin can be connected to a battery or to the main 3.3 V

3.3.2 Description

On, and optionally when it is off. It uses little power in Power-down mode. On the

LPC2141/2/4/6/8, the RTC can be clocked by a separate 32.768 KHz oscillator, or by a

programmable pre scale divider based on the VPB clock. Also, the RTC is powered by its,

which can be connected to a battery or to the same 3.3 V supply used by the rest of the

device.

Fig: 3.6 Architecture of Real Time Clock

3.3.3 Register Description

The RTC includes a number of registers. The address space is split into four

sections by functionality. The first eight addresses are the miscellaneous register group.

The second set of eight locations are the time counter group. The third set of eight

locations contain the alarm register group. The remaining registers control the reference

clock divider.

Chapter-4

INTRODUCTION TO ARDUINO

4.1. ARDUINO:

Arduino is a tool for making computers that can sense and control more of the

physical world than your desktop computer. It's an open-source physical computing

platform based on a simple microcontroller board, and a development environment for

writing software for the board.

Arduino can be used to develop interactive objects, taking inputs from a variety of

switches or sensors, and controlling a variety of lights, motors, and other physical outputs.

Arduino projects can be stand-alone, or they can communicate with software running on

your computer (e.g. Flash, Processing, MaxMSP). The boards can be assembled by hand or

purchased preassembled.

The Arduino programming language is an implementation of Wiring, a similar physical

computing platform, which is based on the Processing multimedia programming

environment.

4.2. ABOUT ARDUINO:

There are many other microcontrollers and microcontroller platforms available for

physical computing. PIC, Raspberry Pi, 8051, and many others offer similar functionality.

All of these tools take the messy details of microcontroller programming and wrap it up in

an easy-to-use package. Arduino also simplifies the process of working with

microcontrollers, but it offers some advantage for teachers, students, and interested

amateurs over other systems.

Inexpensive -Arduino boards are relatively inexpensive compared to other microcontroller

platforms. The least expensive version of the Arduino module can be assembled by hand.

Cross-platform - The Arduino software runs on Windows, Macintosh OSX, and Linux

operating systems. Most microcontroller systems are limited to Windows.

Simple, clear programming environment - The Arduino programming environment is

easy-to-use for beginners, yet flexible enough for advanced users to take advantage of as

well. For teachers, it's conveniently based on the Processing programming environment, so

students learning to program in that environment will be familiar with the look and feel of

Arduino.

Open source and extensible software- The Arduino software is published as open source

tools, available for extension by experienced programmers. The language can be expanded

through C++ libraries, and people wanting to understand the technical details can make the

leap from Arduino to the AVR C programming language on which it's based. Similarly,

you can add AVR-C code directly into your Arduino programs if you want to.

Open source and extensible hardware - The Arduino is based on

Atmel's ATMEGA8 and ATMEGA168microcontrollers. The plans for the modules are

published under a Creative Commons license, so experienced circuit designers can make

their own version of the module, extending it and improving it. Even relatively

inexperienced users can build the breadboard version of the module in order to understand

how it works and save money.

ARDUINO IMAGE:

Fig.4.1. Image of Arduino

4.3 ARDUINO LIBRARY:

Arduino library is a library which consists of various commands and syntaxes of various

functions used to implement our desired program.

4.3.1. ARDUINO COMMANDS for LCD programming:

1. setup():

The setup() function is called when a sketch starts. Use it to initialize variables, pin modes,

start using libraries, etc. The setup function will only run once, after each powerup or reset

of the Arduino board.

2. pinmode():

Configures the specified pin to behave either as an input or anoutput.As of Arduino 1.0.1,

it is possible to enable the internal pullup resistors with the mode INPUT_PULLUP.

Additionally, the INPUT mode explicitly disables the internal pullups.

Syntax:

pinMode(pin, mode)

Parameters:

pin: the number of the pin whose mode you wish to set

mode: INPUT, OUTPUT, or INPUT_PULLUP.

Returns:

None

3. digitalWrite()

Description

Writes a HIGH or a LOW value to a digital pin.

If the pin has been configured as an OUTPUT with pinMode(), its voltage will be set to the

corresponding value: 5V for HIGH, 0V (ground) for LOW.

If the pin is configured as an INPUT, writing a HIGH value with digitalWrite() will enable

an internal 20K pull up resistor. Writing LOW will disable the pullup. The pullup resistor

is enough to light an LED dimly, so if LEDs appear to work, but very dimly, this is a likely

cause. The remedy is to set the pin to an output with the pinMode() function.

Syntax:

digitalWrite(pin, value)

Parameters

pin: the pin number

value: HIGH or LOW

Returns

none

4. digitalRead():

Description

Reads the value from a specified digital pin, either HIGH or LOW.

Syntax:

digitalRead(pin)

Parameters:

pin: the number of the digital pin you want to read (int)

Returns

HIGH or LOW

4. delay()

Description

Pauses the program for the amount of time (in milliseconds) specified as parameter.

Syntax

delay(ms)

Parameters

ms: the number of milliseconds to pause (unsigned long)

Returns

Nothing

4.4.ATMEGA 8 MICROCONTROLLER

Atmega 8 is a high performance, low power Atmel AVR 8-bit microcontroller generally

used along with arduino boot-loader in automatic controlled products and devices. It is

available in 28-pin DIP and TQFP.

4.4.1 Features of Atmega 8

Memory: It has 8 Kb of Flash program memory (10,000 Write/Erase cycles durability),

512 Bytes of EEPROM (100,000 Write/Erase Cycles). 1Kbyte Internal SRAM

I/O Ports: 23 I/O line can be obtained from three ports; namely Port B, Port C and Port D.

SPI (Serial Peripheral interface): ATmega8 holds three communication devices integrated.

One of them is Serial Peripheral Interface. Four pins are assigned to Atmega8 to

implement this scheme of communication.

USART: One of the most powerful communication solutions is USART and ATmega8

supports both synchronous and asynchronous data transfer schemes. It has three pins

assigned for that. In many projects, this module is extensively used for PC-Micro

controller communication.

Analog Comparator: A comparator module is integrated in the IC that provides comparison

facility between two voltages connected to the two inputs of the Analog comparator via

External pins attached to the micro controller.

Analog to Digital Converter: Inbuilt analog to digital converter can convert an analog input

signal into digital data of 10bit resolution. For most of the low end application, this much

resolution is enough.

32 8 General Purpose Working Registers are available.

Pin diagram

Fig. 4.2 Pin Diagram of Atmega 8 Micro Controller

Pin Description

VCC

Digital supply voltage. Magnitude of the voltage range between 4.5 to 5.5 V for the

ATmega8 and 2.7 to 5.5 V for ATmega8L.

GND

Ground. Zero reference digital voltage supply.

PORTB (PB7.. PB0)

PORTB is a port I / O two-way (bidirectional) 8-bit with internal pull-up resistor can be

selected. This port output buffers have symmetrical characteristics when used as a source

or sink. When used as an input, the pull-pin low externally will emit a current if the pull-up

resistor is activated it. PORTB pins will be in the condition of the tri-state when RESET is

active, although the clock is not running.

PORTC (PC5.. PC0)

PORTC is a port I / O two-way (bidirectional) 7-bit with internal pull-up resistor can be



resistor is activated it. PORTC pins will be in the condition of the tri-state when RESET is


PC6/RESET

If RSTDISBL Fuse programmed, PC6 then serves as a pin I / O but with different

characteristics. PC0 to PC5. If Fuse RSTDISBL not programmed, then serves as input

Reset PC6. LOW signal on this pin with a minimum width of 1.5 microseconds will bring

the microcontroller into reset condition, although the clock is not running.

PORTD (PD7.. PD0)

PORTD is a port I / O two-way (bidirectional) 8-bit with internal pull-up resistor can be



resistor is activated it. PORTD pins will be in the condition of the tri-state when RESET is


RESET

Reset input pin. LOW signal on this pin with a minimum width of 1.5 microseconds will

bring the microcontroller into reset condition, although the clock is not running. Signal

with a width of less than 1.5 microseconds does not guarantee a Reset condition.

AVCC

AVCC is the supply voltage pin for the ADC, PC3 .. PC0, and ADC7 .. ADC6. This pin

should be connected to VCC, even if the ADC is not used. If the ADC is used, AVCC

should be connected to VCC through a low-pass filter to reduce noise.

Aref

Analog Reference pin for the ADC.

ADC7 .. ADC6

ADC analog input. There is only on ATmega8 with TQFP and QFP packages / MLF.

Programming an Atmega 8 using and arduino board

Place your Atmega chip into the Arduino board with the divot of the chip facing outward.

Set the jumper to an external power supply and connect a 12V power brick (your board

needs to be externally powered when using the AVR ISP mkII but is not needed with the

AVR tiny ISP). Then, attach the 6-pin female plug of your AVR programmer to the 6 male

header ICSP pins with the plastic nub of the ribbon cable head facing inward.

Fig.4.3 Arduino Board

Fig. 4.4 Arduino Pin Mappnig

CHAPTER-5

RADIO FREQUENCY IDENTIFICATION

5.1.INTRODUCTION

RFID is not a new technology and has passed through many decades of use in military,

airline, library, security, healthcare,sports, animal farms and other areas. Industries use

RFID forvarious applications such as personal/vehicle access control,departmental store

security, equipment tracking, baggage, fast-food establishments, logistics, etc. The

enhancement in RFIDtechnology has brought advantages that are related to

resourceoptimization, increased efficiency within business processes,and enhanced

customer care, overall improvements in businessoperations and healthcare.

RFID stands for Radio Frequency Identification and is aterm that describes a system of

identification. RFID is based on storing and remotely retrieving information or data as it

consists of RFID tag, RFID reader and backend Database. RFID tags store unique

identification information of objects and communicate the tags so as toallow remote

retrieval of their ID. RFID technology depends on the communication between the RFID

tags and RFID readers. The range of the reader is dependent upon its operational

frequency. Usually the readers have their own software running on their ROM and also,

communicate with other software to manipulate these unique identified tags. Basically, the

application which manipulates tag deduction information for the end user, communicates

with the RFID reader to get the tag information through antennas. Many researchers have

addressed issues that are related to RFID reliability and capability. RFID is continuing to

become popular because it increases efficiency and provides better service to stakeholder.

RFID technology has been realized as a performance differentiator for a variety of

commercial applications, but its capability is yet to be fully utilized.

5.2. RFID EVOLUTION

RFID technology has passed through many phases overthe last few decades. The

technology has been used in tracking delivery of goods, in courier services and in baggage

handling. Other applications includes automatic toll payments, departmental access control

in large buildings, personal and vehicle control in a particular area, security of items which

shouldnt leave the area, equipment tracking in engineering firms, etc.

Figure 5.1 shows RFID evolution over the past few decades.

The first RFID application was the "Identification Friend or Foe" system (IFF) and it was

used by the British in the Second World War. Transponders were placed into fighter planes

andtanks, and reading units could query them to decide whether to attack. Successors of

this technology are stillused in armies around the world.The first commercial RFID

application was the "Electronic Article Surveillance" (EAS). It was developed inthe

seventies as a theft prevention system. It was based on tags that can store a single bit. That

bit was readwhen the customer left the store and the system would sound alarm when the

bit was not unset. In theend-seventies RFID tags made its way into the agriculture for

example for animal tagging.In the eighties RFID technology got a boost when Norway and

several US states decided to uses RFID for toll collection on roads. In addition to toll

collection the following decade brought a vast number ofnew applications, such as ski

passes, gasoline cards, money cards, etc.In 1999 the MIT was founded. Its task was to

develop a global standard for item-leveltagging. The Auto-ID was closed in 2003 after

completing the work on the Electronic Product Code (EPC).At the same time the newly

founded continues the work.The probably first paper related to RFID technology was the

landmark paper by Harry Stockman,"Communication by Means of Reflected Power" in

October 1948. The first patent on RFID was issued in1973 for a passive radio transponder

with memory.

5.3. RFID System Working

Most RFID systems consist of tags that are attached to the objects to be identified. Each

tag has its own readonlyor rewrite internal memory depending on the type and

application. Typical configuration of this memory is to store product information, such as

an objects unique ID manufactured date etc. The RFID reader generates magnetic fields

that enable the RFID system to locate objects (via the tags) that are within its range. The

high-frequency electromagnetic energy and query signal generated by the reader triggers

the tags to reply to the query. The query frequency could be up to 50 times per second. As

a result communication between the main components of the system i.e. tags and reader is

established. As a result large quantities of data are generated. Supply chain industries

control this problem by using filters that are routed to the backend information systems. In

other words, in order to control this problem, software such as Savant is used. This

software acts as a buffer between the Information Technology and RFID reader .Several

protocols manage the communication processbetween the reader and tag. These protocols

(ISO 15693and ISO 18000-3 for HF or the ISO 18000-6, and EPC for UHF) begin the

identification process when the reader is switched on. These protocol works on selected

frequency bands (e.g. 860 915 MHz for UHF or 13.56MHz for HF). If the reader is on

and the tag arrives in the reader fields, then it automatically wakes-up and decodes the

signal and replies to the reader by modulating thereaders field. All the tags in the reader

range may reply at the same time, in this case the reader must detect signal collision

(indication of multiple tags). Signal collision is resolved by applying anti-collision

algorithm which enables the reader to sort tags and select/handleeach tag based on the

frequency range (between 50 tags

reader can perform certain

number and writing data into a tag

The reader performs thes

cycle can be seen in figure

5.4. Components

The RFID system consists of various components which

in the above section.

various operations on it. The

of an RFID solution. The RFID system consists of

Figure 5.3):

requency range (between 50 tags to 200 tags) and the protocol used. In this connection the

reader can perform certain operations on the tags such as reading the tags identifi

number and writing data into a tag.

Fig 5.2 A typical RFID System

The reader performs these operations one by one on each tag. A typical RFID s

figure 5.2.

of an RFID System

The RFID system consists of various components which are integrated in a manne

in the above section.This allows the RFID system to deduct the objects (tag)

ions on it. The integration of RFID components enables the implementation

ID solution. The RFID system consists of following five components (as shown in

ol used. In this connection the

reading the tags identifier

tag. A typical RFID system work

grated in a manner defined

tem to deduct the objects (tag) and perform

nables the implementation

following five components (as shown in

Tag (attached with an object, unique identification).

Antenna (tag detector, creates magnetic field).

Reader (receiver of tag information, manipulator).

Communication infrastructure (enable reader/RFID to work through IT infrastructure).

Fig. 5.3 Components of an RFID System

5.5. Tags:

Tags contain microchips that store the uniqueidentification (ID) of each object. The ID is a

serialnumber stored in the RFID memory. The chip is made up of integrated circuit and

embedded in a silicon chip.RFID memory chip can be permanent or changeabledepending

on the read/write characteristics. Read-onlyand rewrite circuits are different as read-only

tag containsfixed data and cannot be changed without re-programelectronically. On the

other hand, re-write tags can beprogrammed through the reader at any time without

anylimit. RFID tags can be different sizes and shapes depending on the application and the

environment atwhich it will be used. A variety of materials areintegrated on these tags. For

example, in the case of thecredit cards, small plastic pieces are stuck on variousobjects,

and the labels. Labels are also embedded in avariety of objects such as documents,

cloths,manufacturingmaterials etc.

.

Fig.5.4 Variety of RFID tags (various shape & sizes)

RFID tags can also be classified by their capabilitiessuch as read and write data.

Fig. 5.5 RFID tags classifications

There are three types of tags: the passive, semi-activeand active. Semi-active tags have a

combination of activeand passive tags characteristics. So, mainly two types oftags (active

and passive) are being used by industry and most of the RFID system. The

essentialcharacteristics of RFID tags are their function to theRFID system. This is based on

their range, frequency,memory, security, type of data and other characteristics.

These characteristics are core for RFID performance anddiffer in usefulness/support to the

RFID system operations. While considering thesecharacteristics, figure 5.6 compares the

active and passivetags.

Fig.5.6 RFID active and passive tags comparison

5.5.1. Tag Frequencies

The range of the RFID tags depends on their frequency.This frequency determines the

resistance to interferenceand other performance attributes. The use/selectionof RFID tag

depends on the application; differentfrequencies are used on different RFID tags. EPC

global and International Standards Organization (ISO) are the major organizations working

to developinternational standards for RFID technologies in theUHF band. These two

organizations are still evolvingand are not fully compatible with each other. Inorder to

avoid the use of different radio frequenciesstandards, most of the international

communities areobligated to comply with the InternationalTelecommunication Union

(ITU) standards.

Thefollowing are the commonly used frequencies:

Microwave :

Works on 2.45 GHz, it has good reader rate even faster than UHF tags. Althoughat this

frequency the reading rate results are notthe same on wet surfaces and near metals,

thefrequency produce better results in applicationssuch as vehicle tracking (in and out

withbarriers), with approximately 1 meter of tags read range.

Ultra High Frequency:

Works within a range of 860-930 MHz, it can identify large numbers oftags at one time

with quick multiple read rate at agiven time. So, it has a considerable goodreading speed. It

has the same limitation asMicrowave when is applied on wet surface andnear metal.

However, it is faster than highfrequency data transfer with a reading range of 3 meters.

High Frequency:

Works on 13.56MHz and has less than one meter reading range but isinexpensive and

useful for access control, itemsidentifications on sales points etc, as it can implanted inside

thin things such as paper.

Low Frequency:

Works on 125 kHz, it has approximately half a meter reading range andmostly used for

short reading range applicationssuch as shops, manufacturing factories, inventory.

5.6. RFID Reader:

RFID reader works as a central place for the RFIDsystem. It reads tags data through the

RFID antennas at a certain frequency. Basically, the reader is anelectronic apparatus which

produce and accept a radio signals. The antennas contains an attached reader,the reader

translates the tags radio signals throughantenna, depending on the tags capacity.

Thereaders consist of a build-in anti-collision schemes and asingle reader can operate on

multiple frequencies. As a result, these readers are expected to collect or write dataonto tag

(in case) and pass to computer systems. For thispurpose readers can be connected using

RS-232, RS-485, USB cable as a wired options (called serial readers) andconnect to the

computer system. Also can use Wi-Fi aswireless options which also known as network

readers. Readers are electronic devices which can beused as standalone or be integrated

with other devicesand the following components/hardware into it.

Fig.5.7. RF reader module

5.7. Advantages & Disadvantages of RFID System

Advantages: High speed

Multipurpose and many

format

Reduce man-power

High accuracy

Complex duplication

Multiple reading (tags)

Disadvantages:

Interference

High cost

signal problem

Chapter-6

LCD DISPLAY

6.1. DEFINITION

LCD (Liquid Crystal Display) screen is an electronic display module and has a wide range

of applications. A 16x2 LCD display is very basic module and is very commonly used in

various devices and circuits. These modules are preferred over seven segments and other

multi segment LEDs.

6.2. ABOUT LCD

The reasons being:

1. LCDs are economical.

2. Easily programmable.

3. Have no limitation of displaying special & even custom characters (unlike in

sevensegments), animations and soon.

6.3. 16x2 Display

A 16x2 LCD means it can display 16 characters per line and there are 2 such lines. In this

LCD each character is displayed in 5x7 pixel matrix. This LCD has two registers, namely,

Command and Data.

The command register stores the command instructions given to the LCD. A command is

an instruction given to LCD to do a predefined task like initializing it, clearing its screen,

setting the cursor position, controlling display etc. The data register stores the data to be

displayed on the LCD. The data is the ASCII value of the character to be displayed on the

LCD. Click to learn more about internal structure of a LCD.

Fig 6.1 pin diagram of LCD

Table 6.1 pin description of LCD

Pin No Function Name

1 Ground (0V) Ground

2 Supply voltage; 5V (4.7V 5.3V) Vcc

3 Contrast adjustment; through a variable resistor VEE

4 Selects command register when low; and data register when high Register Select

5 Low to write to the register; High to read from the register Read/write

6 Sends data to data pins when a high to low pulse is given Enable

7

8-bit data pins

DB0

8 DB1

9 DB2

10 DB3

11 DB4

12 DB5

13 DB6

14 DB7

15 Backlight VCC (5V) Led+

16 Backlight Ground (0V) Led-

Chapter-7

INTRODUCTION TO DC MOTOR

7.1 Electric DC Motor

An electric motor is a device which converts electrical energy to mechanical

energy. A DC motor relies on the fact that, like magnet poles repel and unlike magnetic

poles attract each other. A coil of wire with a current running through it generates a

electromagnetic field aligned with the center of the coil. By switching the current on or off

in a coil its magnet field can be switched on or off or by switching the direction of the

current in the coil the direction of the generated magnetic field can be switched 180.

A simple DC motor typically has a stationary set of magnets in the stator and an

armature with a series of two or more windings of wire wrapped in insulated stack slots

around iron pole pieces (called stack teeth) with the ends of the wires terminating on a

commutator. The armature includes the mounting bearings that keep it in the center of the

motor and the power shaft of the motor and the commutator connections.

The commutator allows each armature coil to be activated in turn. The current in

the coil is typically supplied via two brushes that make moving contact with the

commutator. Now, some brushless DC motors have electronics that switch the DC current

to each coil on and off and have no brushes to wear out or create sparks.

Fig 7.1 working of DC motor

In real life, though, DC motors will always have more than two poles (three is a very

common number). In particular, this avoids "dead spots" in the commutator. You can

imagine how with our example two-pole motor, if the rotor is exactly at the middle of its

rotation (perfectly aligned with the field magnets), it will get "stuck" there. Meanwhile,

with a two-pole motor, there is a moment where the commutator shorts out the power

supply (i.e., both brushes touch both commutator contacts simultaneously). This would be

bad for the power supply, waste energy, and damage motor components as well. Yet

another disadvantage of such a simple motor is that it would exhibit a high amount of

torque "ripple" (the amount of torque it could produce is cyclic with the position of the

rotor).

Fig 7.2. A Simple DC Motor

7.2.Features

100 RPM 12V DC motors with Gearbox

3000 RPM base motor

6mm shaft diameter with internal hole

125 gm weight

Same size motor available in various rpm

No-load current = 60 mA (Max), Load current = 300 mA(Max)

7.3. Motor Construction

7.3.1 Rotor

In an electric motor the moving part is the rotor which turns the shaft to deliver the

mechanical power. The rotor usually has conductors laid into it which carry currents that

interact with the magnetic field of the stator to generate the forces that turn the shaft.

However, some rotors carry permanent magnets, and the stator holds the conductors.

7.3.2 Stator

The stationary part is the stator, usually has either windings or permanent magnets. The

stator is the stationary part of the motors electromagnetic circuit. The stator core is made

up of many thin metal sheets, called laminations. Laminations are used to reduce energy

loses that would result if a solid core were used.

7.3.3.Air gap

In between the rotor and stator is the air gap. The air gap has important effects, and is

generally as small as possible, as a large gap has a strong negative effect on the

performance of an electric motor.

7.3.4.Winding

Windings are wires that are laid in coils, usually wrapped around a laminated soft

iron magnetic core so as to form magnetic poles when energized with current.

Electric machines come in two basic magnet field pole configurations: salient-

pole machine and nonsalient-pole machine. In the salient-pole machine the pole's magnetic

field is produced by a winding wound around the pole below the pole face. In

the nonsalient-pole, or distributed field, or round-rotor, machine, the winding is distributed

in pole face slots. A shaded-pole motor has a winding around part of the pole that delays

the phase of the magnetic field for that pole.Some motors have conductors which consist of

thicker metal, such as bars or sheets of metal, usually copper, although sometimes

aluminum is used. These are usually powered by electromagnetic induction.

7.3.5 Commutator

Fig.7.3 Commutator

A commutator is a mechanism used to switch the input of certain AC and DC

machines consisting of slip ring segments insulated from each other and from the electric

motor's shaft. The motor's armature current is supplied through the stationary brushes in

contact with the revolving commutator, which causes required current reversal and applies

power to the machine in an optimal manner as the rotor rotates from pole to pole. In

absence of such current reversal, the motor would brake to a stop. In light of significant

advances in the past few decades due to improved technologies in electronic controller,

sensorless control, induction motor, and permanent magnet motor fields,

electromechanically commutated motors are increasingly being displaced by externally

commutated induction and permanent magnet motors.

7.4 DC Servo Motor

A servomotor is a rotary actuator that allows for precise control of angular

position, velocity and acceleration. It consists of a suitable motor coupled to a sensor for

position feedback. It also requires a relatively sophisticated controller, often a dedicated

module designed specifically for use with servomotors.

Servomotors are not a different class of motor, on the basis of fundamental operating

principle, but use servomechanism to achieve closed loop control with a generic open loop

motor. In other words, a servomotor is just a regular motor with a sensor installed,

typically to measure angular position during operation.

As the name suggests, a servomotor is a servomechanism. More specifically, it is a closed-

loop servomechanism that uses position feedback to control its motion and final position.

The input to its control is some signal, either analogue or digital, representing the position

commanded for the output shaft.

Fig. 7.4 A Servo Motor

The motor is paired with some type of encoder to provide position and speed

feedback. In the simplest case, only the position is measured. The measured position of the

output is compared to the command position, the external input to the controller. If the

output position differs from that required, an error signal is generated which then causes

the motor to rotate in either direction, as needed to bring the output shaft to the appropriate

position. As the positions approach, the error signal reduces to zero and the motor stops.

The very simplest servomotors use position-only sensing via

a potentiometer and bang-bang control of their motor; the motor always rotates at full

speed (or is stopped). This type of servomotor is not widely used in industrial motion

control, but it forms the basis of the simple and cheap servos used for radio-controlled

models.

More sophisticated servomotors measure both the position and also the speed of the

output shaft. They may also control the speed of their motor, rather than always running at

full speed. Both of these enhancements, usually in combination with a PID

control algorithm, allow the servomotor to be brought to its commanded position more

quickly and more precisely, with less overshooting.

Chapter-8

L293 DRIVER IC

8.1.Dual H-bridge Motor Driver L293D IC

Generally, even the simplest robot requires a motor to rotate a wheel or performs particular

action.Since motors require more current then the microcontroller pin can typically

generate, you need some type of a switch (Transistors, MOSFET, Relay etc.,) which can

accept a small current, amplify it and generate a larger current, which further drives a

motor. This entire process is done by what is known as a motor driver.

Motor driver is basically a current amplifier which takes a low-current signal from the

microcontroller and gives out a proportionally higher current signal which can control and

drive a motor. In most cases, a transistor can act as a switch and perform this task which

drives the motor in a single direction.

Turning a motor ON and OFF requires only one switch to control a single motor in a single

direction. What if you want your motor to reverse its direction? The simple answer is to

reverse its polarity. This can be achieved by using four switches that are arranged in an

intelligent manner such that the circuit not only drives the motor, but also controls its

direction. Out of many, one of the most common and clever design is an H-bridge circuit

where transistors are arranged in a shape that resembles the English alphabet "H".

Fig 8.1. Circuit Diagram of H-bridge

As you can see in the image, the circuit has four switches A, B, C

and D. Turning these switches ON and OFF can drive a motor in

different ways.

Turning on Switches A and D makes the motor rotate clockwise

Turning on Switches B and C makes the motor rotate anti-clockwise

Turning on Switches A and B will stop the motor (Brakes)

Turning off all the switches gives the motor a free wheel drive

8.2. L293D IC:

L293D is a typical Motor driver or Motor Driver IC which allows DC motor to drive on

either direction. L293D is a 16-pin IC which can control a set of two DC motors

simultaneously in any direction, forward and reverse with just 4 microcontroller pins

(without enable pin being considered)

8.2.1. Features of L293D:

Supply voltage can be as large as 36 Volts. This means you do not have to worry much

about voltage regulation.

L293D has an enable facility which helps you enable the IC output pins. If an enable pin is

set to logic high, then state of the inputs match the state of the outputs. If you pull this low,

then the outputs will be turned off regardless of the input states]

The datasheet also mentions an "over temperature protection" built into the IC. This means

an internal sensor senses its internal temperature and stops driving the motors if the

temperature crosses a set point

Another major feature of L293D is its internal clamp diodes. This fly-back diode helps

protect the driver IC from voltage spikes that occur when the motor coil is turned on and

off (mostly when turned off)

Output current capability is limited to 600mA per channel with peak output current limited

to 1.2A (non-repetitive). This means you cannot drive bigger motors with this IC.

However, most small motors used in hobby robotics should work.

This integrated circuit not only drives DC motors, but can also be used to drive relay

solenoids, stepper motors etc.

Fig 8.2 PCB of H-bridge

Fig 8.3.Pin Diagram of L293 and IC

8.2.2 L293D Connections:

There are 16 pins sticking out of this IC and we have to understand the functionality of

each pin before implementing this in a circuit

Pin1 and Pin9 are "Enable" pins. They should be connected to +5V for the drivers to

function. If they pulled low (GND), then the outputs will be turned off regardless of the

input states, stopping the motors. If you have two spare pins in your microcontroller,

connect these pins to the microcontroller, or just connect them to regulated positive 5

Volts.

Pin4, Pin5, Pin12 and Pin13 are ground pins which should ideally be connected to

microcontroller's ground.

Pin2, Pin7, Pin10 and Pin15 are logic input pins. These are control pins which should be

connected to microcontroller pins. Pin2 and Pin7 control the first motor (left); Pin10 and

Pin15 control the second motor(right).

Pin3, Pin6, Pin11, and Pin14 are output pins. Tie Pin3 and Pin6 to the first motor, Pin11

and Pin14 to second motor

Pin16 powers the IC and it should be connected to regulated +5Volts

Pin8 powers the two motors and should be connected to positive lead of a secondary

battery. As per the datasheet, supply voltage can be as high as 36 Volts.

Suppose you need to control the left motor which is connected to Pin3 and Pin6 .As

mentioned above, we require three pins to control this motor - Pin1, Pin2 and Pin7. Here is

the truth table representing the functionality of this motor driver.

Fig 8.4. Interface of motor with L293

CHAPTER-9

TACHOMETER

9.1. Definition:

A tachometer is nothing but a simple electronic digital transducer. Normally, it is used for

measuring the speed of a rotating shaft. The number of revolutions per minute (rpm) is

valuable information for understanding any rotational system. For example, you can also

measure the speed of fans you use.

9.2. SELECTION OF TACHOMETER

Accuracy

Precision

Range

Acquisition Time

Contact type / Non-Contact type

Portable / Fixed

Digital / Analog

Cost

9.3. Types of Tachometers

Analog Tachometer

Has a needle and dial type of interface

No provision for storage of readings

Cannot compute average, deviation, etc.

Digital Tachometer

Has a LCD or LED readout

Memory is provided for storage

9.4. ARDUINO TACHOMETER CONSTRUCTION:

A tachometer is a useful tool for counting the RPM (rotations per minute) of a wheel or

basically anything that spins. The way we built a tachometer is using a transmitter and

receiver. When the link between them is broken, you know that something is spinning and

can execute some code that calculates the current RPM of whatever is spinning to break

the transmitter/receiver link.

9.4.1. OVERVIEW OF WORKING OF THIS TACHOMETER:

The purpose to choose this tachometer is we get a single input, single output system.

The input will come in the form of a signal state change from high (+5v) to low (+0v)

which will occur when the IR break-beam is interrupted and the Arduino will then

increment an internal counter. As time goes on, additional processing and calculation will

occur as interrupts are trigger and the LCD will output the calculated RPM.

To create the IR break-beam, we used an IR LED with a low value resistor so that it

shines very bright. The receiver will be a phototransistor which biases 'on' whenever the IR

LED's light is detected. A computer fan will be placed between the IR link and turned on

so as to continuously generate an interrupt through some additional transistor logic

circuitry. For output, the Arduino LCD interface will be used so that we can output the

final RPM value to the LCD.

9.4.2. PARTS :

The various parts we used for construction of tachometer are described below:

1.ArduinoUno

2.16x2LCD

3.Breadboard

4.5kohm Trimpot

5.Jumper Wire

6.SIPs

7.2x 2n2222 NPN Transistors

8.Infrared LED

9.Phototransistor

10. 10 ohm Resistor

11.100 kilo ohm Resistor

12.15 kilo ohm Resistor

13.Computer Fan

14.Servo motor

9.4.3 PART DETAILS:

The parts used in this project are all listed out above, but the more interesting and

necessary parts are listed out below with a little more detail to describe their function.

ARDUINO UNO:

This is the Arduino board that we will be using to process the IR break-beam pulses

that tell us when the CPU fan has moved. The Arduino will use these pulses along with a

timer to figure out what the current RPM of the fan is.

16x2 LCD:

After the Arduino has figured out what the current RPM is, it will be displayed on

this LCD so that it's obvious to the user.

5 KILO OHM TRIMPOT:

This trimpot will be used for setting the contrast of the 16x2 LCD. It's gives an analog

output varying from +5v to 0, which the LCD translates to a brightness setting.

IR EMITTER DIODE

The photo transistor turns on whenever intense Infrared light shines on it. So

whenever the IR LED is on and shining, it keeps the phototransistor biased 'on'

IR LED is blocked, by...for example a fan blade, the phototransistor is biased 'off'.

2n2222 NPN Transistors

These transistors will mainly be used as level shifters to ensure the pulses output

from the IR break-beam to the Arduino

between.

Schematic overview of the Tachometer:

The break-beam circuit's signal goes to the digital input on the Arduino. This will interrupt

the Arduino so it can count

reading data.

IR EMITTER DIODE AND PHOTO TRANSISTOR:


whenever the IR LED is on and shining, it keeps the phototransistor biased 'on'


2n2222 NPN Transistors:


beam to the Arduino come in the form of +0v to +5v and nothing in

Schematic overview of the Tachometer:

Fig 9.1. circuit diagram tachometer

beam circuit's signal goes to the digital input on the Arduino. This will interrupt

the Arduino so it can count that a pulse has just been registered and the tachometer is


whenever the IR LED is on and shining, it keeps the phototransistor biased 'on', but if the



come in the form of +0v to +5v and nothing in-

beam circuit's signal goes to the digital input on the Arduino. This will interrupt

that a pulse has just been registered and the tachometer is

CHAPTER-10

INTERFACING

10.1. DEFINITION

An interface is the point of interaction with software, or computer hardware, or

with peripheral devices such as a computer monitor or a keyboard. Some computer

interfaces such as a touchscreen can send and receive data, while others such as a mouse or

microphone, can only send data.

10.2. Interface Between 16x2 LCD And Arduino:

Parts used in interfacing:

1.Arduino UNO

2.16x2 LCD

3.Breadboard

4.5k Trimpot

5.Jumper Wire

6.SIPs

Parts List Details:

Luckily the list of parts for this project is very short. The main components are the

16x2 LCD and the Arduino UNO

Arduino UNO:

This is the bare bones and basic CPLD dev board that I developed a few years ago.

The core components are the CPLD, power circuitry and programming circuitry. The

additions from the previous cpld analog to digital converter project were left on the board

since we'll be using them in this project.

Fig 10.1 Arduino UNO

16x2 LCD:

This is the 128 Macrocell CPLD that we'll be using to output the digital PWM

signal to control the 10 LED bar fading-in and fading out.

Fig 10.2 16x2 LCD display

5kTrimpot:

We will use this LED bar to output both the exact 8-bit value that is converted from

analog to digital. A resistor network will be connected up to the LED bar to limit the

amount of current flowing through.

Fig 10.3 Trimpot

Breadboard:

Since the cplddev board is built on protoboard, we need to use sockets, SIPs and

wire wrap to connect everything together.

Fig 10.4 breaboard

SIPs:

SIPs are used to hold all the ICs in place and to make a large connection for the

motors on top of the board. Additionally SIPs are perfect for wire wrapping everything

together.

Schematic Overview:

Since this is purely an output system, we only need to look at the straight forward

interface from Arduino UNO to LCD. As you can see below, the connections are mostly

pin to pin with no funny business.

Fig 10.5 interface circuit

Schematic Specifics:

16x2 LCD Interface

3 control pins and 8 data pins are connected from the Arduino to the LCD. These

are what will tell the LCD what to do and when.

Trimpot Contrast Control

The contrast control uses an analog voltage to tell the LCD how dark or bright the

contrast should be. Using a trimpot here allows for easy adjusting.

Program for Static LCD Display:

#include

LiquidCrystallcd(7, 8, 9, 10, 11, 12); //Initialize LCD

void setup()

{

// set up the LCD's number of columns and rows:

lcd.begin(16, 2);

// Print a message to the LCD.

lcd.print("Current RPM:");

}

void loop()

{

while(1){

//Slow Down The LCD

delay(400);

//Clear The Bottom Row

lcd.setCursor(0, 1);

lcd.print(" ");

//Update The Rpm Count

lcd.setCursor(0, 1);

lcd.print(rpm);

}

10.3.Interface between tachometer and Arduino:

Parts:

1.Arduino UNO

2.16x2 LCD

3.Breadboard

4.5k Trimpot

5.Jumper Wire

6.SIPs

7.2x 2n2222 NPN Transistor

8.Infrared LED

9.Phototransistor

10.10 Resistor

11.100k Resistor

12.15k or 16k Resistor

13.Computer Fan

Parts List Details:

The parts used in this project are all listed out above, but the more interesting and

necessary parts are listed out below with a little more detail to describe their function.

IR Emitter Diode and Phototransistor


whenever the IR LED is on and shining, it keeps the phototransistor biased 'on', but if the

IR LED is blocked, by...for example a CPU fan blade, the phototransistor is biased 'off'.

Fig 10.6 IR transmitter

Fig 10.7 IR receiver

2n2222 NPN Transistors:


from the IR break-beam to the Arduino come in the form of +0v to +5v and nothing in-

between.

Fig 10.8 Transistor

Schematic Overview:

The circuit diagram for this project is a little more complicated.The LCD interface

is simplified to have only 2 control lines and 4 data lines. Then the tachometer IR break-

beam circuit is added on the side to make things a little more complex.

Fig 10.9 LCD display circuit

Schematic Specific:

16x2 LCD Interface

2 control pins and 4 data pins are connected from the Arduino to the LCD. These

are what will tell the LCD what to do and when.

IR Break-Beam Circuit

The break-beam circuit's signal goes to the digital input pin #2 on the Arduino. This

will interrupt the Arduino so it can count that a pulse has just been registered and the

tachometer is reading data.

Hardware circuit after interfacing:

The program for rpm count:

volatile float time = 0;

volatile float time_last = 0;

volatileintrpm_array[5] = {0,0,0,0,0};

void setup()

{

//Digital Pin 2 Set As An Interrupt

attachInterrupt(0, fan_interrupt, FALLING);

}

void loop()

{

int rpm = 0;

if(time > 0)

{

//5 Sample Moving Average To Smooth Out The Data

rpm_array[0] = rpm_array[1];




rpm_array[4] = 60*(1000000/(time*8));

//Last 5 Average RPM Counts Eqauls....

rpm = (rpm_array[0] + rpm_array[1] + rpm_array[2] + rpm_array[3] + rpm_array[4]) / 5;

}

voidfan_interrupt()

{

time = (micros() - time_last);

time_last = micros();

}

CHAPTER-11

SOFTWARE REQIUREMENTS

Software Tools used :

1. Keil Software

2. Arduino IDE

3. Fritzing

In this work Keil software used for c programming for automation of the vehicle.

Program is used to send the message form zonal section to vehicle section. Therefore the

microcontroller activated and controlled the speed of the vehicle.

11.1 About Keil Software

It is possible to create the source files in a text editor such as Notepad, run the

Compiler on each C source file, specifying a list of controls, run the Assembler on each

Assembler source file, specifying another list of controls, run either the Library Manager

or Linker (again specifying a list of controls) and finally running the Object-HEX

Converter to convert the Linker output file to an Intel Hex File. Once that has been

completed the Hex File can be downloaded to the target hardware and debugged.

Alternatively KEIL can be used to create source files; automatically compile, link and

covert using options set with an easy to use user interface and finally simulate or perform

debugging on the hardware with access to C variables and memory. Unless you have to use

the tolls on the command line, the choice is clear. KEIL Greatly simplifies the process of

creating and testing an embedded application.

11.1.1. Keil in Projects

The user of KEIL centers on projects. A project is a list of all the source files

required to build a single application, all the tool options which specify exactly how to

build the application, and if required how the application should be simulated. A

project contains enough information to take a set of source files and generate exactly the

binary code required for the application. Because of the high degree of flexibility required

from the tools, there are many options that can be set to configure the tools to operate in a

specific manner. It would be tedious to have to set these options up every time the

application is being built; therefore they are stored in a project file. Loading the project file

into KEIL informs KEIL which source files are required, where they are, and how to

configure the tools in the correct way. KEIL can then execute each tool with the correct

options. It is also possible to create new projects in KEIL. Source files are added to the

project and the tool options are set as required. The project can then be saved to preserve

the settings.

11.1.2 Simulator/Debugger

The simulator/ debugger in KEIL can perform a very detailed simulation of a micro

controller along with external signals. It is possible to view the precise execution time of a

single assembly instruction, or a single line of C code, all the way up to the entire

application, simply by entering the crystal frequency. A window can be opened for each

peripheral on the device, showing the state of the peripheral. This enables quick trouble

shooting of mis-configured peripherals. Breakpoints may be set on either assembly

instructions or lines of C code, and execution may be stepped through one instruction or C

line at a time. The contents of all the memory areas may be viewed along with ability to

find specific variables. In addition the registers may be viewed allowing a detailed view of

what the microcontroller is doing at any point in time. The vehicle section and zone section

programs are given in appendix.

11.2. Arduino IDE:

The Arduino integrated development environment (IDE) is a cross-platform application

written in Java, and is derived from the IDE for the Processing programming language and

the Wiring projects. It is designed to introduce programming to artists and other

newcomers unfamiliar with software development. It includes a code editor with features

such as syntax highlighting, brace matching, and automatic indentation, and is also capable

of compiling and uploading programs to the board with a single click. A program or code

written for Arduino is called a "sketch".

Writing Sketches

Software written using Arduino are called sketches. These sketches are written in

the text editor. Sketches are saved with the file extension .ino. It has features for

cutting/pasting and for searching/replacing text. The message area gives feedback while

saving and exporting and also displays errors. The console displays text output by the

Arduino environment including complete error messages and other information. The

bottom right-hand corner of the window displays the current board and serial port. The

toolbar buttons allow you to verify and upload programs, create, open, and save sketches,

and open the serial monitor.

Arduino programs are written in C or C++. The Arduino IDE comes with

a software library called "Wiring" from the original Wiring project, which makes many

common input/output operations much easier. Users only need define two functions to

make a runnable cyclic executive program:

setup(): a function run once at the start of a program that can initialize settings

loop(): a function called repeatedly until the board powers off.

Serial Monitor:

The tool called serial monitor helps one to view the data coming from the arduino

board using the in-built serial monitoring interface. It is the most effective communication

method available with a microcontroller. The serial port of the microcontroller provides the

easiest way by which the user and the microcontroller can write their data in the same

medium and both can read each others data. When the serial port of the microcontroller is

connected to the PC and the incoming and outgoing data is monitored using software and

displayed in a window, it forms the simplest text user interface (TUI) setup for the

microcontroller. Serial communication is a very useful debugging tool in the code

development process.

11.3 Fritzing:

Fritzing is the sophisticated new electronics application with the funny name. It is a

powerful tool for making schematics, prototyping circuits, and designing printed circuit

boards. This software

Arduino-based prototype and create a PCB layout for manufacturing.

Three Views

Fritzing can show your project in three views. The default is the Breadboard view

Breadboard View:

Breadboard view is a brilliant simulation that comes with a giant library of parts organized

by brand name and model, so you can drag and drop your exact parts into your diagram. If

the parts you want are not in the library, then you can use the Parts Designer t

them.

Fig 11.1.Sketch of Arduino



boards. This software allows the designer / artist / researcher / hobbyist to document their

based prototype and create a PCB layout for manufacturing.


oard view is a brilliant simulation that comes with a giant library of parts organized


the parts you want are not in the library, then you can use the Parts Designer t



allows the designer / artist / researcher / hobbyist to document their

based prototype and create a PCB layout for manufacturing.


oard view is a brilliant simulation that comes with a giant library of parts organized


the parts you want are not in the library, then you can use the Parts Designer to create

Schematic View:

Studying the schematics is a great way to learn to read them. Reading the schematics is

essential to hack electronics because schematics are product documentation and they tell

you everything about the hardware.



you everything about the hardware.



The Printed Circuit Board (PCB) view:

The breadboard view is a main feature of this software. It helps in designing the PCB for

the prototype created in the above steps. The final design can then be exported for

manufacturing of the PCB. It also has a great auto ro

designing.

Fig 11.2 The Printed Circuit Board (PCB) view

Any change you make in any of these views is automatically updated in the other views.

ed Circuit Board (PCB) view:



manufacturing of the PCB. It also has a great auto routing feature which helps beginners in





uting feature which helps beginners in



integration of electronic speed governor with rfid technology for speed limiting

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