INDEXTOPIC PAGE NO.

01. Cover page01 02. certificate02 03. Decliration03 04. Acknowledgement04 05. Fire fighting robot08 06. Parts09 07. Circuit diagram10 08. Software11 09. Light sensor14 10. The light dependent resistor(LDR16 11. The light dependent resistor cell17 12. Code19 13.LDR switch20 14.Light level sensing circuit21 15.Arduino ATMEGA32822 16.Power25 17.Memory26 18. Communication 27 19. Programming 27 20. Automatic(software) reset 28 21. USB over current protection29 22. Physical characteristics 29 23. Buzzer and bleeper 30 24. Transistors 31 25. Light emitting diodes (LED) 32(a) Function 32(b) Connecting and soldering 32(c) Testing and LEDs 32(d) Colour of LEDs 33(e) Tri-colour LEDs 33

26. Resistors 33(a) Function 33(b) Connecting and soldering 34(c) Resistor values-the resistor colour code 34 27. Small values resistor 34 28. Tolerance of resistor 35 29. Variable resistors 35 30. Capacitors 36 31. Unpolarized capacitor 36 32. Capacitor no. code 38 33. Light dependent resistor 38 34. Project conclusion 39 36. Reference 40 37. Appendix 41

5LIST OF FIGURETOPIC PAGE N0.1. Fire fighting robot line diagram082. Circuit diagram103. LDR164. LDR Cell175. Voltage divider186. Light level sensing circuit207. ATMEGA328-Pinpoint diagram228. ATMEGA328-Circuit diagram239. Motor2910. Water pump 3011. Buzzer and bleeper 3112. Transistors 3113. Transistor circuit symbols3114. LED3215. Colour LEDs3216. Tri-colour LEDs 3317. Resistor 3318. Variable resistor 3519. Unipolarised capacitor 37

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AbstractThe electrical components required for low budget robotics projects are now readily available. Because of this, robotics research is no longer limited to institutions that can devote extensive resources for new technology. Smaller robotics projects provide a good base for students to apply a variety of engineering skills necessary to develop these low cost embedded systems.The project chosen by this group was to design a robotic device capable of maneuvering itself through a base, locating a light source placed within a floor and extinguishing the light intensity. It competed against other robots to see which design could locate and extinguish the light source in the shortest amount of time.By the end of the project, the robot could reliably navigate the contest maze and extinguish the candle. By using a combination of dead reckoning and landmark recognition, the robot can avoid maze obstacles and enter maze rooms.

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Fire Fighting RobotThe need for a device that can detect and extinguish a fire on its own is long past due. Many house fires originate when someone is either sleeping or not home. With the invention of such a device, people and property can be saved at a much higher rate with relatively minimal damage caused by the fire. Our task as electrical engineers was to design and build a prototype system that could autonomously detect and extinguish a fire. Also aims at minimizing air pollution. In this Project we design a Fuzzy based Microcontroller controlled Robot. It is the Robot that can move through a model structure, find a burning oil derrick (lit candle) and then extinguish it with help of a Blower. This is meant to simulate the real world operation of a Robot performing a fire extinguishing function in an oilfield. Fuzzy logic provided an appropriate solution to the otherwise complex task of mathematically deriving an exact model for the non-linear control system upon which conventional control techniques could then be applied. The fuzzy inference system was designed to act as a PID-like controller. We are using the Popular 8 bit Microcontroller the ATMEGA328 Microcontroller. Program code to control the fire fighting robot is written in C language & programmer is ARDUINO UNO BOARD.the differential amplifier to any particular light level making it ideal as a simple light sensor project circuit.

motormicrocontrollerMotor driver

Lightsensor

Pump driverWater pumpbuzzer

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PARTS;-1 light sensor LDR 12 atmega 328 microcontroller 13 variable resistor 100K 14 buzzer 6V 15 water pump 9V 16 gear motor 30 RPM 27 wheel 28 cursor wheel 19 chasis 110 led 5MM 311 battery 9v 312 regulated IC 7805 1 13 some resistors

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CIRCUIT DIAGRAM

10SOFTWARE/* Analog input, analog output, serial output

Reads an analog input pin, maps the result to a range from 0 to 255and uses the result to set the pulsewidth modulation (PWM) of an output pin. Also prints the results to the serial monitor.

The circuit: * potentiometer connected to analog pin 0. Center pin of the potentiometer goes to the analog pin.side pins of the potentiometer go to +5V and ground * LED connected from digital pin 9 to ground

created 29 Dec. 2008modified 9 Apr 2012by Tom Igoe

This example code is in the public domain.

*/

// These constants won't change. They're used to give names// to the pins used:11

constintanalogInPin = A0; // Analog input pin that the potentiometer is attached to // Analog output pin that the LED is attached to

intsensorValue = 0; // value read from the potintoutputValue = 0; constint ledpin1 = 6;constint ledpin2 = 7;constint ledpin3 = 8; // value output to the PWM (analog out)

void setup() { // initialize serial communications at 9600 bps:

pinMode(ledpin1 , OUTPUT);pinMode(ledpin2 , OUTPUT);pinMode(ledpin3 , OUTPUT);

}

void loop() { // read the analog in value:sensorValue = analogRead(analogInPin); // map it to the range of the analog out:12outputValue = map(sensorValue, 0, 1023, 0, 255); // change the analog out value:

// print the results to the serial monitor:

if(outputValue< 150 ) {digitalWrite(ledpin1 , HIGH);digitalWrite(ledpin2 , LOW);digitalWrite(ledpin3 , LOW);

delay(20);}else if(outputValue>= 150 ) {digitalWrite(ledpin1 , LOW);digitalWrite(ledpin2 , HIGH);digitalWrite(ledpin3 , HIGH);

delay(2000);

}

}

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Light Sensors

ALight Sensorgenerates an output signal indicating the intensity of light by measuring the radiant energy that exists in a very narrow range of frequencies basically called light, and which ranges in frequency from Infra-red to Visible up to Ultraviolet light spectrum.TheLight Sensoris a passive devices that convert this light energy whether visible or in the infra-red parts of the spectrum into an electrical signal output. Light sensors are more commonly known as Photoelectric Devices or Photo Sensors because the convert light energy (photons) into electricity (electrons).Photoelectric devices can be grouped into two main categories, those which generate electricity when illuminated, such asPhoto-voltaicsorPhoto-emissivesetc, and those which change their electrical properties in some way such asPhoto-resistorsorPhoto-conductors. This leads to the following classification of devices. Photo-emissive Cells These are photodevices which release free electrons from a light sensitive material such as caesium when struck by a photon of sufficient energy. The amount of energy the photons have depends on the frequency of the light and the higher the frequency, the more energy the photons have converting light energy into electrical energy. Photo-conductive Cells These photodevices vary their electrical resistance when subjected to light. Photoconductivity results from light hitting a semiconductor material which controls the current flow through it. Thus, more light increase the current for a given applied voltage. The most common photoconductive material is Cadmium Sulphide used in LDR photocells. Photo-voltaic Cells These photodevices generate an emf in proportion to the radiant light energy received and is similar in effect to photoconductivity. Light energy falls on to two semiconductor materials sandwiched together creating a voltage of approximately 0.5V. The most common photovoltaic material is Selenium used in solar cells.

14 Photo-junction Devices These photodevices are mainly true semiconductor devices

such as the photodiode or phototransistor which use light to control the flow of electrons and holes across their PN-junction. Photojunction devices are specifically designed for detector application and light penetration with their spectral response tuned to the wavelength of incident light.The Photoconductive CellAPhotoconductivelight sensor does not produce electricity but simply changes its physical properties when subjected to light energy. The most common type of photoconductive device is thePhotoresistorwhich changes its electrical resistance in response to changes in the light intensity.Photoresistors areSemiconductordevices that use light energy to control the flow of electrons, and hence the current flowing through them. The commonly usedPhotoconductive Cellis called theLight Dependent ResistororLDR.

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The Light Dependent Resistor

Typical LDRAs its name implies, theLight Dependent Resistor(LDR) is made from a piece of exposed semiconductor material such as cadmium sulphide that changes its electrical resistance from several thousand Ohms in the dark to only a few hundred Ohms when light falls upon it by creating hole-electron pairs in the material.The net effect is an improvement in its conductivity with a decrease in resistance for an increase in illumination. Also, photoresistive cells have a long response time requiring many seconds to respond to a change in the light intensity.Materials used as the semiconductor substrate include, lead sulphide (PbS), lead selenide (PbSe), indium antimonide (InSb) which detect light in the infra-red range with the most commonly used of all photoresistive light sensors beingCadmium Sulphide(Cds).Cadmium sulphide is used in the manufacture of photoconductive cells because its spectral response curve closely matches that of the human eye and can even be controlled using a simple torch as a light source. Typically then, it has a peak sensitivity wavelength (p) of about 560nm to 600nm in the visible spectral range.

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The Light Dependent Resistor Cell

The most commonly used photoresistive light sensor is theORP12Cadmium Sulphide photoconductive cell. This light dependent resistor has a spectral response of about 610nm in the yellow to orange region of light. The resistance of the cell when unilluminated (dark resistance) is very high at about 10Ms which falls to about 100s when fully illuminated (lit resistance).To increase the dark resistance and therefore reduce the dark current, the resistive path forms a zigzag pattern across the ceramic substrate. The CdS photocell is a very low cost device often used in auto dimming, darkness or twilight detection for turning the street lights ON and OFF, and for photographic exposure meter type applications.

Connect one pin of LDR to 5v and another pin to A0 input.This is a Light sensor usingLDR and Arduino, you can make it either Shadow detector or light detector by simply changing the code given below.

Connect one pin of 10k resistor to GND and another pin to A0 inputThe code below makes the arduino as a Shadow detector, to make it light detector you change the Condition statements, If Else partchange different things and get different outputs.. Enjoy

18CODE:

int LDR = 0; //analog pin to which LDR is connected, here we set it to 0 so it means A0intLDRValue = 0; //thats a variable to store LDR valuesintlight_sensitivity = 500;//This is the approx value of light surrounding your LDRvoid setup() { Serial.begin(9600); //start the serial monitor with 9600 buad pinMode(13, OUTPUT); //we mostly use13 because there is already a built in yellow LED in arduino which shows output when 13 pin is enabled }void loop(){ LDRValue = analogRead(LDR); //reads the ldrs value through LDR which we have set to Analog input 0 A0 Serial.println(LDRValue); //prints the LDR values to serial monitor delay(50); //This is the speed by which LDR sends value to arduino if (LDRValue 1F) | Unpolarised (< 1F) | Real Values | Variable & trimmersAlso see: Capacitance and Uses of Capacitors

FunctionCapacitors store electric charge. They are used with resistors in timingcircuits because it takes time for a capacitor to fill with charge. They are used to smooth varying DC supplies by acting as a reservoir of charge. They are also used in filter circuits because capacitors easily pass AC (changing) signals but they block DC (constant) signals. CapacitanceThis is a measure of a capacitor's ability to store charge. A large capacitance means that more charge can be stored. Capacitance is measured in farads, symbol F. However 1F is very large, so prefixes are used to show the smaller values. Three prefixes (multipliers) are used, (micro), n (nano) and p (pico): 1. means 10-6 (millionth), so 1000000F = 1F 2. n means 10-9 (thousand-millionth), so 1000nF = 1F 3. p means 10-12 (million-millionth), so 1000pF = 1nF

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Capacitor values can be very difficult to find because there are many types of capacitor with different labelling systems! There are many types of capacitor but they can be split into two groups, polarised and unpolarised. Each group has its own circuit symbol. Polarised capacitorExamples: Circuit symbol:

Unpolarised capacitors (small values, up to 1F)Examples: Circuit symbol: Small value capacitors are unpolarised and may be connected either way round. They are not damaged by heat when soldering, except for one unusual type (polystyrene). They have high voltage ratings of at least 50V, usually 250V or so. It can be difficult to find the values of these small capacitors because there are many types of them and several different labelling systems! Many small value capacitors have their value printed but without a multiplier, so you need to use experience to work out what the multiplier should be! For example 0.1 means 0.1F = 100nF. Sometimes the multiplier is used in place of the decimal point: For example: 4n7 means 4.7nF.37Capacitor Number CodeA number code is often used on small capacitors where printing is difficult: the 1st number is the 1st digit, the 2nd number is the 2nd digit, the 3rd number is the number of zeros to give the capacitance in pF. Ignore any letters - they just indicate tolerance and voltage rating. For example: 102 means 1000pF = 1nF (not 102pF!)For example: 472J means 4700pF = 4.7nF (J means 5% tolerance).

Light Dependent Resistor (LDR)An LDR is an input transducer (sensor) which converts brightness (light) to resistance. It is made from cadmium sulphide (CdS) and the resistance decreases as the brightness of light falling on the LDR increases. A multimeter can be used to find the resistance in darkness and bright light, these are the typical results for a standard LDR: Darkness: maximum resistance, about 1M. Very bright light: minimum resistance, about 100. For many years the standard LDR has been the ORP12, now the NORPS12, which is about 13mm diameter. Miniature LDRs are also available and their diameter is about 5mm. An LDR may be connected either way round and no special precautions are required when soldering.

38Project ConclusionThe robot can reliably navigate the contest maze and extinguish the light source. By using a combination of dead reckoning and landmark recognition, the robot can avoid maze obstacles and enter maze rooms. Other sensors allow the robot to pinpoint the location of the light source. Further improvements could be added to the project that would allow the robot to place better in future contests. A tone detector could be added that would allow the robot to be activated once a 3 kHz to 4 kHz tone is sounded (instead of a simple push button), simulating the noise emitted from a smoke detector. In addition, the robot could be programmed to adjust for uneven floors, requiring modifications to the robot chassis. Finally, the software implementation could be changed to allow the robot to return to its starting position once the light source has been extinguished.

39ReferencesContest References:1. http://www.trincoll.edu/events/robot/Rules/default.asp2. http://www.trincoll.edu/events/robot/Results04/default.asp

Robotics References:3.http://members.verizon.net/~vze2b2zf/robotpage.html4.http://abrobotics.tripod.com/Snuffy/snuffy.htm

Part References:5.http://bd.thrijswijk.nl/thrsim11/68hc11/about2.htm.6.http://abrobotics.tripod.com/Snuffy/uvtron.htm7.http://www.acroname.com8.http://www3.sympatico.ca/donroy/handson.html9. http://www.srl.gatech.edu/education/ME3110/primer/motors.htm10. http://lancet.mit.edu/motors/index.html11. http://e-www.ATMEL.com/webapp/sps/site/overview.jsp 12. http://www.woodweb.com/knowledge_base/Servo_vs_stepper_motors.html13. http://www.cs.uiowa.edu/~jones/step/14. http://www.cctc.demon.co.uk/stepper.htm15. http://www.euclidres.com/apps/stepper_motor/stepper.html16. http://www.robotics.com/motors.htmlBook References17.Software and Hardware Engineering, Fredrick M. Cady, Copyright 1997, Oxford University Press, Inc.40

APPENDIX

COMPONENT NAME QUALITYPRICE IN RUPECE

Light sensorLDR50.00

AT MAGA 328 Microcontroller300.00

Variable resister100K25.00

Buzzer6V50.00

Water pump9V125.00

Gear motor30RPM235.00

Wheel40.00

Chases30.00

Led5MM15.00

Battery9V39.00

Regulated IC780580.00

Some resisters50.00

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