Design & Implementation of Color Sensor

Presentation on Design & Implementation of Color Sensor.

Introduction

Light is a physical phenomenon.When the components of light are absorbed or transmitted in different proportions by an object, color occurs. The color of an object is apparent only when light strikes the object. For color to be perceived, the viewer must have blue, green, and red receptors. Depending upon its chemical make-up, matter has the ability to absorb, reflect or transmit visible light.

When all the components of visible light are absorbed by matter, the object is said to be black.On the other hand, if all the components of visible light are reflected or transmitted by the object, the object is considered white or clear. The visible light spectrum is a small part of the electro-magnetic spectrum. The visible spectrum has a wavelength range of about 380 to 740 nm. Human eye can perceived only the visible light.

Wavelength & frequency interval of different colors

Color Name	Wavelength Interval nm	Frequency Interval THz
Violet	380-450	668-789
Blue	450-495	606-668
Green	495-570	526-606
Yellow	570-590	508-526
Orange	590-620	484-508
Red	620-750	400-484

Objectives

The main objective of our project is to detect the color of an object. Our target is to detect ten colors.The target colors are Black, Green, Red, Blue, Yellow, Magenta, Yellow-lemon,Pink,
Gray, White.
To relate color system wherein color purity and mixings is identified perfectly and is independent of human observations or subjective judgments.
Possible Outcome

To detect the color of an object with high precision even under varying environment conditions, such as fluctuations in the ambient temperature or variations of incidence light on the object to be measured.

Experimental Design

A color sensor includes a light receiving element for receiving the light from an object(target) illuminated by the lights from the light emitting sources and a circuit arrangement for producing output signals representing the color of the object.

Experimental Design


Op-amp

The op-amp is basically a differential amplifier having a large voltage gain, very high input impedance and low output impedance. Most of the time operational amplifiers are used to compare voltages of unequal magnitudes. They are called ``operational'' amplifiers, because they can be used to perform arithmetic operations (addition, subtraction, multiplication) with signals.

Op-amp Circuit Notation


V ₊ : non-inverting input
V- : inverting input
V_out : output
Vs₊: positive power supply
Vs-: negative power supply
Pin Connection of LM741


Analog-to-digital converter (ADC)

An analog-to-digital converter (A/D) takes an analog voltage or current and after a certain amount of time it produces a digital output code that represents the analog input.

Simply, an analog-to-digital converter is a device which converts continuous signals to discrete digital numbers.

General Block Diagram (ADC)



Pin diagram & free running connection


Pin diagram of ADC0804


Free running connection

Microcontroller

Microcontroller is a programmable integrated circuit which contains Processor, memory and input/output functions in a single chip. It is a microprocessor emphasizing high integration. In contrast to a general-purpose microprocessor, the microcontroller integrates additional elements such as read write memory for data storage, read-only memory for program storage, EEPROM for permanent data storage, peripheral devices, and input/output interfaces.

Pin diagram (PIC16F84A)


Pin function


Circuit Diagram




Program

TRISA = 0
TRISB = 255
Dim a As Byte
PORTA = 0
WaitMs 10
main:
PORTA = 0
a = PORTB
If a < 11 Then PORTA = 1 '//Black
If a > 6 Then
If a < 27 Then PORTA = 2 '//Blue
Endif
If a > 26 Then
If a < 31 Then PORTA = 3 '//green
Endif
If a > 39 Then
If a < 44 Then PORTA = 4 ''// Pink
Endif
If a > 44 Then
If a < 50 Then PORTA = 5 '//Red
Endif
If a > 49 Then
If a < 57 Then PORTA = 6 '//Megenta
Endif
If a > 56 Then
If a < 63 Then PORTA = 7 '// White
Endif
If a > 64 Then
If a < 73 Then PORTA = 8 '//Yellow
Endif
If a > 89 Then
If a < 93 Then PORTA = 9 '//Gray
Endif
If a > 92 Then
If a < 96 Then PORTA = 10 '//Yel+lem
WaitMs 200
Goto main
Result

Our project is designed for detection of ten colors. But we have detected eight colors successfully. The detected eight colors are red, green, yellow, yellow-lemon, pink, gray, black & white.

Error

We can’t detect two colors. The colors are blue & magenta. This two colors are overlapped with green & red.
Limitation

1. The major limitation of our project is that it can’t detect the object which contains number of colors.
2. One limitation of this project is that it can’t display the color name. But it is possible to display the color name with the help of LCD display by proper programming.
3. Our blue sensor can’t work properly. So we can’t detect the blue color as well as other color.
4. We can’t filter the color perfectly.

Future study & improvement

1. To display the detected color name.
2. To increase the number of detected color.
3. To detect number of colors even exist as a narrow strip within the object.
4. Sort objects by color

Reference

1. “Digital Systems Principles and Applications” By, Ronald J. Tocci, Neal S. Widmer & Gregory L. Moss
2. “Digital Logic and Computer Design” By, M. Morris Mano
3. “Operational Amplifiers and Linear Integrated Circuits” , Sixth edition By, Robert F. Coughlin and Frederick F. Driscoll

Submitted By Anup Kumar Das and Prashanta Kumer Sarker

INTELLIGENT HOME SECURITY SYSTEM

Presentation on INTELLIGENT HOME SECURITY SYSTEM

INTRODUCTION:

Considering some present problems of a building or an area in our country, we have found that providing security is one of the main concerns. So we thought about a security system which will help in providing continuous safety to us and our assets. The basic aim of this project was to investigate different ways of intruders breaking into residential areas and to adopt an appropriate security system. We can protect our family and valuables with this microcontroller based security system that will let us rest our head knowing that should anyone trying to break into our home or building, an alarm will go on and the security will be alerted immediately.

OBJECTIVES:

1. The objectives of our project are as following:
2. To provide security to the residential and commercial areas.
3. To detect intruders entering into restricted regions.
4. To make a reliable security system.
5. To make a system with minimum cost and power consumption.

POSSIBLE OUTCOMES:

1. If a person wants to enter into the secured area in a wrong manner, corresponding LED and alarm will be on. The state is not changed until the system is reset.
2. If anyone tries to break the door of a flat in the absence of the owner, the security person will be alerted through the same process.
3. The system is also capable to detect fire and there is also an IR pair in the room to detect unwanted person in the house in the absence of the owner in case the person enters through the window or in any other way.
4. There is a switch to control the two IR pairs in the house because these two pairs will be on if there is no one in the house.

OVERVIEW OF THE PROPOSAL

BLOCK DIAGRAM

CIRCUIT DIAGRAM:

SIMULATION RESULT:

ADVANTAGES:

1. Cheap cost.
2. Negligible power consumption.
3. Low maintenance cost.
4. Flexible.
5. Reliability of operation.
6. Low installation cost.
7. Minimum load variation.

LIMITATIONS:

1. Coverage range of IR transmitters used are approximately 20 feet. So there will be need of “repeaters” to cover large areas.
2. We have proposed for a reliable system as far as we could have done. But like the other security systems, it is also breakable.
3. There is a chance of false alarm in the system but the probabilities are very small.
4. There is an effect of sunlight on infrared communication between transmitter and the receiver. The system is more reliable in the absence of daylight.

FUTURE DEVELOPMENTS:

1. With proper research, the system can be made wireless.
2. We can use CCTV with the existing system in order to increase reliability.
3. We can also use flashlight and camera with proper zooming abilities.
4. By using infrared lasers, we can increase the coverage area to a greater extent.

POWER CONSUMPTION:

For our project, the required dc voltage is approximately 5v and the required current is about 0.16A. So the required power for one hour is 0.8 Wh. Power consumption in a day will be around 19.2 Wh and the power required in a month will be 576 Wh or 0.576 KWh approximately. Sometimes the circuit may vary in case of the required supply voltage but we can assume the variation as constant. We can see that the project is very low power consuming which is one of our main objectives.

CONCLUSION:

The microcontroller based home security system has been introduced. Experimental results shows that the microcontroller is a reliable instrument to control the system. The system is applicable to different sizes of areas and high controlling capability over them. The simple design of it allows minimum of maintenance work and the price performance relationship is cost effective. Despite of having some limitations, our system is more applicable in the prospective of our country.

REFERENCES:

1. http//www_ee.stanford.edu/~jmk/pubs/proc.ieee.2.97.pdf
2. http://www.datasheetcatalog.com/datasheetspdf/…/PIC16F84A.shtml.
3. http://www.chipswinner.com/DS/LM339.pdf.
4. http://www.toshiba.com/taec/components2/datasheet_sync//152/59.pdf.
5. Orcad Pspice 9.2 (simulation software).
6. MPLAB IDE v 7.41 (microcontroller programming software)
7. http://en.wikipedia.org/wiki/Light_emitting_diode
8. http://en.wikipedia.org/wiki/Crystal_oscillator
9. http//en.wikipedia.org/wiki/Transistor

Submitted by RIZWAN HAIDER CHOWDHURY & A.K.M SAIFUL ISLAM

Satellite Based Train Monitoring System

Presentation on Satellite Based Train Monitoring System

Introduction

Transportation is a large & important part of the economy & the need for transportation increase continuously. Train is one of the main & biggest transportation system in Bangladesh. Everyday thousands of people travel in train to different destinations. For good customer service it is their responsibility to have a good management system.

So it is necessary for them to have a clear idea about the actual position, speed, time to reach destination of a particular train at every instant.

But unfortunately there is no such system that could give them clear idea about the situation. What they do is, they divide the total network in kilometer blocks & approximates the position of a particular train.

Existing Monitoring System

The existing conventional monitoring system most of the times relay on the oral communication through telephonic and telegraphic conversations. In our railway system, when train crosses a station & sets for next station the rail track between the two station is locked & no other train are permitted to enter in that locked section. A station can only senses a train within its 1200 ft. range.

When a train crosses this limit a station can only tell the train is somewhere between the two station but cannot tell in which particular position & at what speed the train is heading to the next station. This miscommunication may lead to wrong allocation of the track for trains, which ultimately leads to the train collision.

When a train passes a station it blocks the total link up to next station. If the train makes too late to reach the next station then they check the link manually. If problem exists it takes hours to know for them about the problem.

In our project we have implemented a Satellite based Train Monitoring System that would give the status of a train at any instant. This status can be viewed by the train control room as well as any passenger who want to access it.

Objectives:

1. To monitor the status of a particular train at any instant.
2. This system will also provide a way to minimize the accidents & helps to minimize the human errors which cause accidents.
3. Passengers who will travel by train can know the status of their train by internet at any time. This would help him to make decision about his traveling.
4. The monitoring could be done from various points which will reduce human errors.

Project Overview

GPS (global positioning system) is a device that can give its own longitude, latitude, speed etc. from the orbiting satellites. There are 24 satellites orbiting our earth. These satellites transmit transparent data to earth. A GPS receives the data from the satellites those can be viewed by the device & calculates its status.

Fig: AVL VT310 GPS-GPRS module.

Fig: Flow Diagram of GPS based train monitoring system

Fig: Position updating in Google Map from client end

In our system we will use GPS-GSM/GPRS module to collect the position information of a train at every instant & passes this information to a web-server via man –machine interface.

As new data being inserted to the database, it will update the location information containing speed, distance from a particular station etc. of the train at the client end when requested.

Man machine interface can also become a useful tool for preciously locating a train in a track. An operator in the train will continuously update the track number in the computer connected with the GPS.

With the introduction of man machine interface , our system should look somewhat like this:

The data served by GPS & from the computer will be accumulated by the server & the server will be able to give accurate position with track number & will make the decision when & in which track the train should arrive at the next crossing.

Important Attributes:

Our system will be cost effective. This system

1. will reduce the work force required;
2. will definitely reduce train accident;
3. Late running of trains can be prevented to large extend.

Conclusion

The implementation of our proposed system will contribute a lot in automation of our railway system. The introduction of digital maps could make the system even better & as the positions could be accurately measured.

We have made a small step in making our train controlling & monitoring system automatic & error free. We have to go a long way to make it fully functional. Our government has a big role to play in these regards.

Submitted by BY Rajesh Mozumder and Jiban Chandra Bhowmik

IMPLEMENTATION OF A VERTICAL AXIS WIND TURBINE

Presentation on IMPLEMENTATION OF A VERTICAL AXIS WIND TURBINE

RENEWABLE ENERGY

RENEWABLE ENERGY IS ENERGY GENERATED FROM NATURAL RESOURCES—SUCH AS SUNLIGHT, WIND, TIDES, AND GEOTHERMAL HEAT—WHICH ARE RENEWABLE. NOW A DAYS RENEWABLE ENERGY IS ONE OF THE MOST IMPORTANT TOPIC IN POWER GENERATION.

ADVANTAGES OF RENEWABLE ENERGY

1. We can use it repeatedly without depleting it.
2. No contribution to global warming.
3. No polluting emissions.
4. Low cost applications when counting all costs.
5. Saving on health and its costs.

RENEWABLE ENERGIES

1. KNOWN RENEWABLE ENERGIES ARE
2. SOLAR
3. WIND
4. BIOMASS
5. HYDRO etc…

TYPES OF WIND TURBINES
Horizontal axis
Turbines that rotate around a horizontal axis are more common. Horizontal-axis wind turbines (HAWT) have the main rotor shaft and electrical generator at the top of a tower, and are usually pointed into the wind
Vertical axis
Vertical-axis turbines rotate on a vertical axis.
VERTICAL AXIS
Vertical-axis turbines rotate on a vertical axis. Vertical-axis wind turbines (or VAWTs) have the main rotor shaft arranged vertically. Key advantages of this arrangement are that the turbine does not need to be pointed into the wind to be effective. This is an advantage on sites where the wind direction is highly variable. VAWTs can utilize winds from varying directions.
VAWT SUBTYPES

1. DARRIEUS WIND TURBINE
2. GIROMILL
3. SAVONIUS WIND TURBINE

ADVANTAGES

1. A MASSIVE TOWER STRUCTURE IS LESS FREQUENTLY USED.
2. THEY HAVE LOWER WIND STARTUP SPEEDS THAN HAWTS.
3. THEY MAY BE BUILT AT LOCATIONS WHERE TALLER STRUCTURES ARE PROHIBITED.
4. VAWTS SITUATED CLOSE TO THE GROUND CAN TAKE ADVANTAGE OF LOCATIONS.
5. THEY MAY HAVE A LOWER NOISE SIGNATURE.
6. SIMPLE MANTAINENCE.
7. SIMPLICITY OF MANUFACTURE AND INSTALATION.
8. DOES NOT DEPEND ON WIND DIRECTION

VAWT DISADVANTAGES

1. MOST PRODUCE ENERGY AT ONLY 50% OF THE EFFICIENCY OF HAWTS IN LARGE PART BECAUSE OF THE ADDITIONAL DRAG THAT THEY HAVE AS THEIR BLADES ROTATE INTO THE WIND.
2. A VAWT THAT USES TO HOLD IT IN PLACE PUTS STRESS ON THE BOTTOM BEARING AS ALL THE WEIGHT OF THE ROTOR IS ON THE BEARING.
3. HAVING ROTORS LOCATED CLOSE TO THE GROUND WHERE WIND SPEEDS ARE LOWER DUE TO WIND SHEAR, THEY MAY NOT PRODUCE AS MUCH ENERGY AT A GIVEN SITE AS A HAWT WITH THE SAME FOOTPRINT OR HEIGHT.

DARRIEUS WIND TURBINE
FOR IMPLEMENTING PURPOSE WE CHOOSE THE DARRIEUS TYPE VERTICAL AXIS WIND TURBINE. THE REASONS BEHIND IT ARE GIVEN BELOW.
DARRIEUS TURBINES, WHICH ARE LIFT-DRIVEN, HAVE A HIGHER POWER POTENTIAL THAN THE HORIZONTAL, OR DRAG-DRIVEN TURBINES. THE MAIN DRAWBACK WITH THEIR DESIGN IS THEIR INABILITY TO SELF-START. DARRIEUS TURBINES REQUIRE AN EXTERNAL ENERGY SOURCE TO BRING THE DEVICE TO A MINIMUM ROTATIONAL SPEED
COMPONENTS
Base: The base will be a truncated pyramid, about 3ft tall. This base was made by angles. It has different levels, one at ground level, one hold the way up and one at the top. There is two bearing mounted in the top and bottom of the top levels.

Shaft: Sitting in these bearings will be the shaft. The shaft is a 9ft tall length of steel mechanical tubing, with initial dimensions of 1” in the main part, 0.75” at bottom.
Blades: The dimensions of the blades are 20inch in length and 10inch in wide. Eight prototype blades were made to connect to the turbine. The blades were connected to the turbine body by two nuts at the bottom and the top.

Turbine structure : Attached to the shaft by set screws are 2 circle of steel bar which. These were fabricated at the workshop. The circles are joined to the shaft by two small circles.

GENERATOR
IN THIS DESIGN WE USED A PERMANENT MAGNET DC MOTOR. IT WAS REQUIRED TO USE SYNCHRONOUS GENERATOR BUT WE USED PARMANENT MAGNET MOTOR BECAUSE IT IS AVAILABLE IN THE LOCAL MARKET.

FINAL SETUP

WIND POWER CALCULATION
WIND POWER, P = 0.5 X RHO X A X V³
WHERE,
P = POWER IN WATTS
RHO = AIR DENSITY (ABOUT 1.225 KG/M³ AT SEA LEVEL, LESS HIGHER UP)
A = ROTOR SWEPT AREA, EXPOSED TO THE WIND (M²)
V = WIND SPEED IN METERS/SEC
WIND TURBINE POWER
P = 0.5 x rho x A x Cp x V³ x Ng x Nb
Where,
P = power in watts.
rho = air density.
A = rotor swept area, exposed to the wind (m²)
Cp = Coefficient of performance
V = wind speed in meters/sec
Ng = generator efficiency
Nb = gearbox/bearings efficiency.
WIND SPEED VS. TURBINE POWER

FUTURE IMPROVEMENTS
While the prototype did not perform as well as initially hoped, with a few changes to the design this should improve greatly:

1. The most important area of improvement is the turbine body construction, which could have been done by aluminum.
2. The blades are not perfectly shaped by making the blades perfectly shaped the efficiency of the turbine can be improved
3. Change that would improve the performance is altering the design of the arms.
4. Some of these improvements would be to purchase better bearings, install better bearing support, and add weatherproofing. A better bearing would enable the turbine to turn more freely; reducing the starting torque and making everything work much more smoothly

Submitted by SAYEDUR RAHMAN and SAQUIB SHARIF

Implementation of One cycle control technique for Buck converter

PRESENTATION ON Implementation of One cycle control technique for Buck converter.

INTRODUCTION:

The one cycle control technique is proposed to control the duty ratio ‘d’ of a switch such that in each cycle the average value of a switched variable of the switching converter is exactly equal to or proportional to the control reference in the steady state or in a transient.

The control technique is general and applicable to all types of PWM, soft-switched switching converters for either voltage or current control in continuous or discontinuous conduction mode.

OBJECTIVE:

Our aim to control the Buck converter output by one cycle control technique.

We Apply the control technique for the following condition By Orcad simulation.

1. Rejection to Power Source Perturbation
2. Following the Control Reference
3. Variation of load.

One-Cycle Control Circuit Diagram

One-Cycle Control Theory

A switch operates according to the switch function k ( t ) at a frequency fs = l/Ts,

where T_on+ T_off= Ts.

The input signal X(t) at the input node of the switch is chopped by the switch and transferred to the output node of the switch to form a switched variable y(t).

Y(t) = k ( t ) x ( t ) (5)

Suppose the switch frequency fs Is much higher than the frequency bandwidth of either the input signal x(t) or the control reference Vref.

The switched variable y(t) at the output node of the switch is the product of the input signal x(t) and the duty-ratio d ( t ) ; therefore, the switch is nonlinear

SIMMULATION OF ONE-CYCLE CONTROL CIRCUIT DIAGRAM:

At Normal condition:

The Buck converter Output:

(1) Rejection of Input Variation

(2) Output follows the control Reference:

Variation of Load:

Normal output at load 150 ohm.

If we Change the load 150ohm to 200ohm than the output

METHODOLOGY:

1. Theoretical study and analysis of One cycle control technique .
2. Simulate the One cycle control of Buck converter circuit with ORCAD 9.2.
3. Collect the necessary components.
4. Test each portion of circuit individually.
5. Implementation the One cycle control of Buck converter circuit practically.

Experimental Setup

Opto-coupler wave Shape

Flip-flop output waveform

Inverted amplifier output

Buck Converter

Integrator output wave shape:

Comparator Output

Future Works:

The One-Cycle Control technique will be applied for the following type of Switches.

1. Constant ON-time switch.
2. Constant OFF-time switch
3. Variable switch.

CONCLUSION:

converters with One Cycle Control are capable of rejecting the power source perturbations completely the average value of the switched variable at the switch output node is able to follow the control reference within one cycle. The One-Cycle Control concept is straightforward and its implementation circuits are simple, yet it provides excellent control.

REFERENCE:

1. One-Cycle Control of Switching Converters. Keyue M. Smedley, Member, IEEE, and

Slobodan Cuk, Senior Member, IEEE.

An Integrated One-Cycle Control Buck Converter With Adaptive Output and Dual Loops for Output Error Correction. Dongsheng Ma, Member, IEEE, Wing-Hung Ki, Member, IEEE, and Chi-Ying Tsui, Member, IEEE.

One cycle control of three-phase VAR compensators and active power filters. Sandeep Bala (99007013) Department of Electrical Engineering, Indian Institute of Technology, Bombay, April 2003.

Keyue Ma Smedly. “Control Art of Switching Converter” California Institute of Technology, Pasadena, California, June 21, 1990.

Submitted by Ratan Kanti Das and Sufal Chandra Dey.