ELG4135-Electronics IIIELG4135-Electronics IIIProfessor: Dr. Riadh Habash Professor: Dr. Riadh Habash

Presentation date: Nov 28Presentation date: Nov 28thth, 2006, 2006

Group Members:Group Members:

Yichen FanYichen FanGefei ZhouGefei Zhou

Zhanglei SongZhanglei Song

Infrared Entrance Monitor SystemInfrared Entrance Monitor System

OutlineOutline

IntroductionIntroduction System AnalysisSystem Analysis Simulation ResultsSimulation Results Further ImprovementFurther Improvement ConclusionConclusion

IntroductionIntroduction We design and implement the basic infrared systemWe design and implement the basic infrared system This system can be used in many areas such as:This system can be used in many areas such as:

Door entrance monitoring Door entrance monitoring Guest/visitor monitoring Guest/visitor monitoring Home security Home security

Infrared techniques are widely used in many areas. It Infrared techniques are widely used in many areas. It has a wavelength of approximately between 750nm and has a wavelength of approximately between 750nm and 1mm. 1mm.

System DescriptionSystem Description

The infrared systems contains two parts-transmitter part The infrared systems contains two parts-transmitter part and receiver part.and receiver part.

The transmitter part uses an IR led to radiates the infrared The transmitter part uses an IR led to radiates the infrared signal.signal.

The receiver part uses an IR receiver module to receive the The receiver part uses an IR receiver module to receive the signal.signal.

The IR led (Light Emitting Diode) is an infrared led which The IR led (Light Emitting Diode) is an infrared led which can produces an infrared wave between 750nm to can produces an infrared wave between 750nm to 950nm.950nm.

The IR receiver module is an receiving device which can The IR receiver module is an receiving device which can detect an infrared light and produce an inputs to the detect an infrared light and produce an inputs to the receiver.receiver.

Overview when the beam is onOverview when the beam is on

The transmitter part will generate a modulated signal to The transmitter part will generate a modulated signal to the IR (Infrared) led through which it can radiates an the IR (Infrared) led through which it can radiates an infrared signal to the receiver.infrared signal to the receiver.

The receiver will recognize the radiated signal by the IR The receiver will recognize the radiated signal by the IR (Infrared) receiver module and make an alternative (Infrared) receiver module and make an alternative square wave voltage (0 and +5V) as the input of the square wave voltage (0 and +5V) as the input of the receiver circuit. This will make the whole circuit works receiver circuit. This will make the whole circuit works and the LED will be on which means the signal between and the LED will be on which means the signal between them is connected well.them is connected well.

Overview when the beam is offOverview when the beam is off

When the IR (Infrared) beam between the transmitter When the IR (Infrared) beam between the transmitter and the receiver is broken, the IR (Infrared) receiver and the receiver is broken, the IR (Infrared) receiver module will recognize there is no more infrared signal module will recognize there is no more infrared signal and it will produce a constant high voltage (+5V) as the and it will produce a constant high voltage (+5V) as the input of the receiver circuit.input of the receiver circuit.

This will shut down the whole circuit and the LED will be This will shut down the whole circuit and the LED will be off which indicates that the beam between the off which indicates that the beam between the transmitter and the receiver is being blocked. transmitter and the receiver is being blocked.

Transmitter BoardTransmitter Board

Square-wave oscillators Square-wave oscillators made by using two 555 timer ICs set up as “astable” multivibrators made by using two 555 timer ICs set up as “astable” multivibrators

Resistors & CapacitorsResistors & Capacitors set the IC frequency set the IC frequency

DiodesDiodes create a “symmetrical” output create a “symmetrical” output

IR LEDIR LED pulsed at 38kHz and transmit the IR beam to receiver pulsed at 38kHz and transmit the IR beam to receiver

Transmitter descriptionTransmitter description

555 Timer Description555 Timer Description Initialize capacitor discharged Initialize capacitor discharged Lower comparator sets the FFLower comparator sets the FF Charging through R1Charging through R1 Charge timeCharge time

Tc = 0.693 * R1 * CTc = 0.693 * R1 * C Upper comparator resets the Upper comparator resets the

FFFF Discharging through R2Discharging through R2 Discharge timeDischarge time

Td = 0.693 * R2 * CTd = 0.693 * R2 * C FrequencyFrequency F = 1/(Tc +Td) = 1/(0.693* R1+R2)*C)F = 1/(Tc +Td) = 1/(0.693* R1+R2)*C)

SimulationSimulation

Output of IC1 (250Hz)Output of IC1 (250Hz)

Simulation (Cont)Simulation (Cont)

Output of IC2 (38KHz)Output of IC2 (38KHz)

Infrared Entrance Monitor Infrared Entrance Monitor ReceiverReceiver

Block DiagramBlock Diagram Circuit AnalysisCircuit Analysis Simulation Data ComparisonSimulation Data Comparison ImprovementImprovement

Block DiagramBlock Diagram

IR Beam Detector

Receiver

0-5 5kHz Square wave output

Charging capacitor

Light ON

Receiver 5V DC output Unable to pass the capacitor Light Off

Relay Off

Relay On

Circuit AnalysisCircuit Analysis

Data Comparison -- XSC1Data Comparison -- XSC1

Data Comparison -- XSC2Data Comparison -- XSC2

Data Comparison – Channel B Data Comparison – Channel B

BlockedBlocked

Data Comparison -- XSC1Data Comparison -- XSC1

Data Comparison -- XSC2Data Comparison -- XSC2

Video of The Simulation ResultsVideo of The Simulation Results

ConclusionConclusion

We have successfully implemented the circuits We have successfully implemented the circuits in the multisim as well as the hands work.in the multisim as well as the hands work.

The simulation meets the theoretical results and The simulation meets the theoretical results and also it meets the results implemented from the also it meets the results implemented from the hands work.hands work.

The design can be used for commercial The design can be used for commercial purpose.purpose.

Further Improvement for our circuitFurther Improvement for our circuit

Add a counter to the relay to counts the Add a counter to the relay to counts the number of people entering the shop or the number of people entering the shop or the number of cars entering the entrance.number of cars entering the entrance.

Change the values of capacitors or the Change the values of capacitors or the input voltage to make the discharging time input voltage to make the discharging time shorter or longer depends on what we shorter or longer depends on what we need.need.

ReferencesReferences

Iguana Labs, “Oscillators, Pulse Generators, Capacitors and the Iguana Labs, “Oscillators, Pulse Generators, Capacitors and the 555 Timer IC”, 555 Timer IC”, http://www.iguanalabs.com/555kit.htmhttp://www.iguanalabs.com/555kit.htm, August 6, August 6thth, , 20042004

John Hewes, “Relays”, John Hewes, “Relays”, http://www.kpsec.freeuk.com/components/relay.htmhttp://www.kpsec.freeuk.com/components/relay.htm, 2006, 2006

Wikipedia, the free encyclopedia, “Counter”,Wikipedia, the free encyclopedia, “Counter”, http://en.wikipedia.org/wiki/Counterhttp://en.wikipedia.org/wiki/Counter, 31 October 2006 , 31 October 2006

Data sheet, Data sheet, http://pdf1.alldatasheet.com/datasheet-pdf/view/5642/MOTOROLA/http://pdf1.alldatasheet.com/datasheet-pdf/view/5642/MOTOROLA/SN74LS107D.htmlSN74LS107D.html, 2006, 2006

Thank you very much Thank you very much

Especially thank you for the Professor Especially thank you for the Professor Habash and the TAs who helping us a lot Habash and the TAs who helping us a lot on the project.on the project.

Questions and Concerns?Questions and Concerns?