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Table of Contents Content
List of Figures..IIChapter 1
1.2 Development Methods
2.1 Optical flow or image subtraction in
human detection from infrared camera
on mobile robot
22.1.2 Research Highlights
3.1 Statement of Problem
3.2 Advanced Technology
4.1 Design & Development of Hardware
4.1.1 Total Circuit Internal Working
4.2 Regulated Power Supply
4.3 Encoder HT12E
4.4 Decoder HT12D
4.5Encoding & Decoding Process
4.5.1 What is encoding & decoding
4.5.2 HT12D &HT12E
4.6 DPDT Switch Connection with Encoder
4.7 RF Transmitter & Receiver
Result & Discussion
Conclusion & Future Scope
6.2 Future Scope
ABSTRACTThe mainaim theproject istodesign LIVEHUMANBEINGDETECTION WIRELESS REMOTE CONTROLLED ROBOTAT89S51, RF remote control,HT12D Decoder, HT12E Encoder, PIR sensor, DriverIC and DC motor.In the existing method we are controlling the robot by using IR remote which cancontrol therobot in the lineof sight only. The main disadvantage of thismethod iswe can control the robot up to shortest range only and also during the earthquakes person cannot move into the places along with the robot for detection of the live person inside the area where person movement is not possible.In the proposed method we are using RF remote control which can be used to control the robot at any range. To detect the live person we are using PIR sensorcalledaspassiveinfraredsensorwhichisusedtodetectthepersonswhethertheyarealiveornot. The remote uses certain range of Radio frequencies which is used to transfer the commands from the remote to the robot. By using this we can change the directions of the robot. Programs are developed in Embedded C. Flash magic is used for loading programs into Microcontroller.Used to detect the live persons where earthquakes are generated.Low cost, easy to use for rural areas, automated operation, and low power consumption.
ILIST OF FIGURES
Name of Figure
Transmitter & power Supply Circuit
LM7805 Regulator Pin Diagram
HT12E Pin Diagram
HT12E (Tx Side)
HT12E Parallel Input & Serial Output
HT12D Serial Input & Parallel Output
DPDT Switch Connection with Encoder
II Chapter 1
Live Human Being Detection Wireless Remote Control Robot is used to detectthe live persons. This robot is very helpful in detecting live persons under the buried andpillarsetc.,wheneverthereisanyearthquakeoccurred,tsunamioranyotherbuildingcollapse. At the time ofthese effects people may fell down and buriedunder the bridgesand under the pillars etc., in some cases we cant get into that felled contactsand we canthelp them. In such cases to save them immediately we use this robot. This robots job is todetect the live personandindicate the signal tothe helpers.
1.2 Development MethodsTo implement thismechanism weused discrete components tocontrol the robot,movement, and indicating signal purpose. We used ARM7 microcontroller to control theentire robot function it has vast advantages, and PIR sensor to detect live persons. DCmotors are used to for robot movement and it can be controlled by user.When we send this robot to such places where man movement is not possible, It willtry to find out the live persons. The user will control the robot movement with the remote.The liveperson can bedetectedby thebody temperature radiation.Normally human body will have 96.8to105ctemperaturerange. ThePIR (passiveinfrared)sensor willbedesigned like that itwill activate when it willdetect that much temperature.This project issophisticated in the market since it is a real time embedded project. Intheadvancedmarkettheserobotsarefurtherimplemented using the new technologies like GSM, GPS and LCD displays. Using theseGSM technologies we canoperate therobot fromthe far distances and wecan identify thelocation using GPS. Using Camera at the Robot and LCD display at the user section we canoperate the device accurately and it provides live section. Gear wheels can provide theaccurate movement in all areas.
1 Chapter 2LITERATURE REVIEW2.1 Optical flow or image subtraction in human detection from infrared camera on mobile robot
Perceiving the environment is crucial in any application related to mobile robotics research. In this paper, a new approach to real-time human detection through processing video captured by a thermal infrared camera mounted on the autonomous mobile platform mSecuritTMis introduced. The approach starts with a phase of static analysis for the detection of human candidates through some classical image processing techniques such as image normalization and thresholding. Then, the proposal starts a dynamic image analysis phase based in optical flow or image difference. Optical flow is used when the robot is moving, whilst image difference is the preferred method when the mobile platform is still. The results of both phases are compared to enhance the human segmentation by infrared camera. Indeed, optical flow or image difference will emphasize the foreground hot spot areas obtained at the initial human candidates detection.
2.1.2 Research highlights
Use of infrared camera on mobile robot.Comparison of performance of optical flow vs. image subtraction in motion detection. Introduction of the mSecurit mobile robot.
3.1 Statement of ProblemThere is manydifferent kind of catastrophe innatural andman-madedisaster :earthquake,flooding, hurricaneand they causedifferentdisasterarea like collapsedbuilding,landslideorcrater.Duringtheseemergencysituations,andspeciallyinurban disaster,manydifferentpeopleare deployed(policeman, firefightersand medical assistance).They need to cooperate to savelives, protect structural infrastructure, and evacuate victims to safety. In these situations, human rescuers must make quick decisions under stress, and try to get victims to safety often at their own risk. They must gatherdetermine the location and status of victimsand the stability of the structures asquickly aspossibleso thatmedicsand firefighterscanenterthedisasterareaand save victims.Allofthese tasks are performed mostly by human and trained dogs, often in very dangerous and risky situations. This is why since some years, mobile robots have been proposed to help them and to perform tasks that neither humans dogs nor existing tools can do. For thisproject,wewillfocusedonlyonrobotswhichwillwork inadisasterenvironment ofmanmade structure, like collapsed buildings.3.2 Advanced TechnologyTheadventofnewhighspeedtechnologyandthegrowingcomputercapacityprovidedopportunityfornewrobotcontrolsandrealizationofnewmethodsofcontrol theory. This technical improvement together with the need for high performance robots created faster, more accurate and more intelligent robots using new robots control devices, new drives and advanced control algorithms. This Project deals with live personal detection robot is based on 8 bit Microcontroller. This Robot follows which is drawn overthe surface. Here we are using PIR sensor for detect the which are detect human.The project is mainly used in the DEBRIS for Earth quake rescue. Internally it consists of IR sensors. The infrared sensors are used to sense the live persons. All the above systems are controlled by the Microcontroller. In our project we are using the popular 8 bit microcontroller .TheMicrocontroller isused tocontrol themotors. Itgets thesignalsfrom the PIR sensors and it drives the motors according to the sensor inputs. Two DC gearmotors are used to drive the robot.
4.1 DESIGN AND DEVELOPMENT OF HARDWAREMAIN CIRCUIT DIAGRAM AND ITS OVERALL OPERATION
Fig 4.1: Transmitter and power supply circuit8
4.2 INTERNAL WORKING EXPLANATION:Mainly the block diagram consists of following parts:
Power supply circuit
HT12E Encoder ICThe devices that act as input are
Power supply Switch box
The devices that act as output are
RF transmitter4.3 Total circuit internal working explanation:The main aim is to design LIVE PERSON DETECTION ROBOT USING RF WIRELESSCOMMUNICATION.This robot is developed by using LPC2148 micro controller to it RF receiver is connected and driver IC and DC motors are used. The robot movement is controlled by using RF remote control. This remote consists of RF transmitter through this remote robot movementiscontrolledbysendingcommandstorobotthroughRFtransmitterwhich receives data through RF receiver connected to controller and then based on commands received by controller for changing direction of robot. To change the position of robot RF transmitter is used which is used to change toparticulardirection. ConsiderTo moverobot inforward directionthen particularcommand is send to controller through RF remote this remote internally contains RF encoder, The RF encoder to transmit the position change wirelessly to robot. HT12E is RF encoder which receivesthe parallel data fromthe controller andconverts thisparallel datainto serial data and to transmit the serial data to RF transmitter through Dout pin in RF encoder TE pin should always be kept high to transmit it to data pin of RF transmitter. Then serial data is received by the data pin of transmitter and is send out wirelessly by the antenna to RF receiver present at robot. The RF receiver connected to robot receives the data through antenna and sends to controller. The sent data by the RF transmitter is received by the RF receiver and send that data RF decoder which decodes the signal ie., serial data into parallel by using HT12D. Thesignal is received by DIN pin and sends out using data pins and through data pins data issend to controller. Then controller sends received data to Driver IC which is used to changethe direction of robot.
4.3.1 REGULATED POWER SUPPLYA variable regulated power supply, also called a variable bench power supply ,is one where you can continuously adjust the output voltage to your requirements. Varying the output of the power supply is the recommended way to test a project after having double checked parts placement against circuit drawings and the partsplacement guide. This type of regulation is ideal for having a simple variable bench power supply. Actually this is quite important because one of the first projects a hobbyist should undertake is the construction of a variable regulated power supply. While a dedicated supply is quite handy, it's much handier to have a variable supply on hand, especially for testing.
Regulator:The filter output is not a pure d.c and it is not a constant d.c voltage it varies with the fluctuations in the main power supply. But our requirement is to get constant d.cpower supply. The regulator can give constant d.c power supply. These are two types ve power supply and +ve power supply. The 78xx series gives+vepowersupply (78indicates+ve andxxindicatesany voltagevalue).TheLM79xxseries gives ve power supply ( 79 indicates ve and xx indicates anyvoltage value). In our project AT89c51, HT12E and HT12Dneeds +5v power.LM7805gives +5vconstant powersupply.
Fig.220.127.116.11 LM7805 regulator pin diagram
LM7805 Features Output Current up to 1A
Output Voltages of 5, 6,8, 9, 10, 12, 15, 18, 24V
Thermal Overload Protection
Short Circuit Protection
Output Transistor Safe Operating Area Protection4.3.2 ENCODER HT12EHT12Eis anencoder integrated circuitof 212series of encoders. They are paired with 212series of decoders for use in remote control system applications. It is mainly used in interfacing RF and infrared circuits. The chosen pair of encoder/decoder should have same number of addresses and data format.
Simply put, HT12E converts the parallel inputs into serial output. It encodes the 12 bit parallel data into serial for transmission through an RF transmitter. These 12 bits are divided into 8 address bits and 4 data bits.
HT12E has a transmission enable pin which is active low. When a trigger signal is received on TE pin, the programmed addresses/data are transmitted together with the header bits via an RF or an infrared transmission medium. HT12E begins a 4-word transmission cycle upon receipt of a transmission enable. This cycle is repeated as long as TE is kept low. As soon as TE returns to high, the encoder output completes its final cycle and then stops.
Fig 18.104.22.168: Pin Diagram- HT12E4.3.3 DECODER HT12D
HT12Dis adecoder integrated circuitthat belongs to 212series of decoders. This series of decoders are mainly used for remote control system applications, like burglar alarm, car door controller, security system etc. It is mainly provided to interface RF and infrared circuits.They are paired with 212series of encoders. The chosen pair of encoder/decoder should have same number of addresses and data format.
In simple terms, HT12D converts the serial input into parallel outputs. It decodes the serial addresses and data received by, say, an RF receiver, into parallel data and sends them to output data pins. The serial input data is compared with the local addresses three times continuously. The input data code is decoded when no error or unmatched codes are found. A valid transmission in indicated by a high signal at VT pin.
HT12D is capable of decoding 12 bits, of which 8 are address bits and 4 are data bits. The data on 4 bit latch type output pins remain unchanged until new is received.4.4 ENCODING AND DECODING PROCESS4.4.1 What is Encoding and Decoding:
In simple words, encoding is wrapping up the data. The data could be anything like simple binary data (in the form of 1s and 0s) or it could be an audio signal or it could be certain text. But here we are dealing with the encoding that is used for binary signals. The wrapped data is called as a Packet. This packet is sent through a medium (Through wire or wireless) to the decoder part where it gets unwrapped or decoded. Yes, now what you are thinking is right, it is exactly similar to posting an envelope. Encoding is when you put the letter into envelope, the postman is medium to take the envelope to the recipient and when recipient opens the envelope then it is called decoding.So, essentially to apply encoding and decoding technique in our digital world we need three entities: (1). A sender or in electronics sense it is Transmitter. (2). To receive this sent data we need a receiver. (3). And of course we need an address of the receiver. The role of address in electronics is played by address lines.
4.4.2 HT12D and HT12EEncoder-decoder IC pair. In market, it is available with the name as HT12E and HT12D. The 12 in the name means 8-address lines and 4-data lines while E and D letters represents Encoder and decoder respectively.HT12E(Transmitter side) Fig22.214.171.124: HT12E(Tx Side)Lets first take the Encoding side. The encoder has four input lines. Theses lines are used to give input which we want to encode. In encoding, we are wrapping up the data which means if we want to send a binary signal 1001 to other end, we have to make data pins as 1001. Now, to make data pin like this, what we need to do is to give high or 5 volts (which in digital means 1) to pins D0 and D3 while we have to provide pins D1 and D2 with 0 volt. (Ground). This altogether gives us 1001 which is transmitted out from the Data out pin of the HT12E. The input given to data pin is in parallel form which is being transmitted into serial form from the data output pin. The figure below will clear this:
Fig 126.96.36.199: HT12E Parallel Input & Serial OutputOur data is now been encoded and will be transmitted. The transmission medium could be anything, it could be our regular wire, or wireless. In this tutorial, we are going to use our steady single core wire which we use to provide connections in breadboard (nothing fancy!).
The data flows in serial form through the wire and reaches the other end i.e. to the receiver. Receiver now decodes this signal. So, lets see how decoder works:HT12D (Receiver side):Below is the pin diagram of HT12D decoder IC.
Fig 188.8.131.52: HT12D(Rx Side)Now neglect all the pins for this moment and just concentrate on Din (Data in) pin and the for Data lines pin. The encoded data which is coming from the transmitter side goes into the Data in (Din) pin. The data which was in serial order gets decoded and the output is generated at the for data line pins in same order as that on transmitter pin.
When there is no input at the data in pin, the output pins i.e. data lines remains high.
The figure below shows the decoding taking place in HT12D
Fig 184.108.40.206: HT12D Serial Input & Parallel OutputRole of Address Lines:When using a single pair of encoder-decoder IC, we generally leave the address pins as it is i.e. we do not connect them to either ground or VCC. But what if there is more than one decoder but only single encoder. In that case we need to give an address to the data that it might travel to specific decoder only and our data should not leak at unnecessary decoders. This is very useful in wireless communication.
To define an address, what we need to do is to connect specific address pins to the ground on both encoder and decoder side; remember that the order of connecting the address pins to the ground must be same. See the animation below for; it will remove all the twists in your mind:
Oscillator Pins:When we first hear the word oscillations, the first thing that comes in our mind is the to and fro waving motion, yup as always you are correct. The role of oscillator in digital electronics is to produce waves which are in Sine wave form or rectangular wave form. The device used to generate this waveform is called Oscillator. The waveform generated by the oscillator is called as Pulses (like our heart beat). So, in digital world the oscillator works identical to our Heart. Unfortunately, we will not be able to see the oscillator device itself because in HT12D and HT12E, the oscillator comes inbuilt, what we have to do is to put a resistor between the oscillators pins. But, in our coming tutorial over microcontrollers, the need of oscillator is must, so we will learn about it in that tutorials only.
VT Pin (Valid Transmission):The valid transmission pin in decoder shows that the transmitter address and the receiver address are same and is ready to receive the data from the encoder side.
During implementation of the circuit, we will see how to get notification about the valid transmission through this pin.
So, now we are loaded with all the essentials needed to implement Encoder-Decoder circuit. Lets start implementing one:Components Required:1.IC- HT12E/HT12D (generally comes in pair).
2.Breadboard with complete Power supply.
4.Resistors (Four 125 ohm for LEDs)
(750k ohm for oscillator of Encoder)
(27k ohm for oscillator of Decoder).
5.Reset Switch (4).
6.Battery (6-24 volts)
Step1.Take the power supply circuit and insert the encoder and decoder ICs at some distance. Also provide the VCC and ground to the pins (Pin number 9 ground and pin number 18 VCC for both the ICs). See the figure below:
Step2.Now, we will first make the encoder part. Insert the 750k ohm resistor in pin number 15 and 16 i.e. you have to short both the pins using this resistor. Connect the Transmission Enable pin (TE) to ground. This action will enable the IC to transmit the data through data out pin. Now connect four reset switches in data line. Remember, reset switch has two legs. One will go into the data line and the other one will go to ground. So, whenever you will press the switch, the pin will get connected to the ground. See the figure below which how actually you have to connect the switches:
Step3.Yup, our encoder part is completed. You are ready to encode your secret data. But there should be something which shows the reception of data at data output lines. We are using LEDs for that purpose. The LED will glow when data is received. So, lets put down hands over decoder circuit.
Connect all for LEDs separately with the four data lines of decoder IC. To have a better understanding, I am not showing the 125 ohm resistor. If you dont know how to connect resistor or having doubt over polarity, thenclick hereto have quick tutorial.
Also connect or short pin number 15 and 16 with 27k ohm resistor.
Step4.Thats it, we are almost done. Now connect our last LED at the VT pin of the decoder. When circuit is given power, the LED at VT pin glows, it gives the indication that decoder address is matched with the encoder and ready to have Valid Transmission. At last connect the data out and data in of encoder and decoder respectively. The circuit will work in the same way as shown in the window below.
Click the button D0, D1, D2, or D3 at the encoder circuit to view the working of our encoding and decoding circuit.The complete circuit on breadboard will look like this. The bold blue line in centre of the breadboard connects the data in and data out pins. You can also do this with real breadboard by taking the wire through the slot provided in centre of breadboard. This makes the circuit look less messy:
4.5 DPDT SWITCH CONNECTION WITH ENCODER
Fig 4.5.1: DPDT Switch Connection with Encoder4.6 RF TRANSMITTER & RECEIVERRF TRANSMITTER:General Description:The ST-TX01-ASK is an ASK Hybrid transmitter module.ST-TX01-ASK is designed by the Saw Resonator, with an effective low cost, small size,and simple-to-use for designing.Frequency Range:315 / 433.92 MHZ.Supply Voltage: 3~12V.Output Power : 4~16dBmCircuit Shape: Saw
Applications*Wireless security systems*Car Alarm systems
*Remote controls.*Sensor reporting*Automation systems
RESULT AND DISCUSSION5.1 RESULTTheprojectLIVEPERSONDETECTIONROBOTUSINGRFWIRELESSTECHNOLOGYTRANSMITTER SECTION has been successfully designed and tested.It has been developed by integrating features of all the hardware components used. Presence of every module hasbeen reasoned out and placed carefully thus contributing to the best workingof the unit. Secondly, using highly advanced ICs and with the help of growing technology theproject has been successfully implemented.
CONCLUSION & FUTURE SCOPE6.1 CONCLUSION
TheprojectLIVEPERSONDETECTIONROBOTUSINGRFWIRELESSTECHNOLOGYTRANSMITTER SECTION has been successfully designed and tested.It has been developed by integrating features of all the hardware components used. Presence of every module hasbeen reasoned out and placed carefully thus contributing to the best workingof the unit. Secondly, using highly advanced ICs and with the help of growing technology theproject has been successfully implemented.
BIBLIOGRAPHYBIBLIOGRAPHY1. Citation from book Electronic Components- D.V.Prasad Wireless Communications- Theodore S. Rappaport Mobile Tele Communications- William C.Y. Lee2. Citation from website www.alldatasheet.com33