Room Switch Light Control Using Visitor Counter free essay sample

Department of Electronics and communication Engineering MINI PROJECT REPORT 2011 CERTIFICATE Certified that this project report â€Å"AUTOMATIC ROOM LIGHT CONTROLLER WITH BIDIRECTIONAL VISITOR COUNTER† is the bona fide work of ? SHILPA VINOD† who carried out the project work under my supervision. HEAD OF THE DEPARTMENT SUPERVISOR INTERNAL EXAMINER EXTERNAL EXAMINER 4 ACKNOWLEDGEMENT Before we get into the thick of things, we present our wholehearted compliments, with higher regards and warm thanks to one and all, who were the bone behind the sinews of this project. We give all glory and honour to Almighty God whose blessings and help made this endeavour a success. We wish to express our sincere thanks to our Principal, Dr. C. E. Krishnan, for providing an opportunity to undertake this project. We hereby acknowledge our sincere thanks to Prof. Arumuga Samy, our H. O. D. for his invaluable remarks and supervision in completing this project work successfully. Also we would like to express our boundless thanks and gratitude to Mr. Deepak P. , Mr. Mahesh P S, Mr. Vishnu, Lecturers in ECE Dept. for their valuable guidance and suggestions in the whole course of our mini project activity. It would be unfair if we do not mention the invaluable contribution and timely co-operation extended by staff members of our dept. We would like to thank our Institution without which this project would have been a distant reality. We also extend our heartfelt thanks to our family and well wishers. Not the least, but the most, we are grateful to all the 6th semester students of this institution, our beloved companions for the inspiration and the co-operation they have shown at all levels of our work. 5 ABSTRACT This Project ? Automatic Room Light Controller with Bidirectional Visitor Counter? s a reliable circuit that takes over the task of controlling the room lights as well us counting number of persons / visitors in the room very accurately. When somebody enters into the room then the counter is incremented by one and the light in the room will be switched ON and when any one leaves the room then the counter is decremented by one. The light will be only switched OFF until all the persons in the room go out. The total number of persons inside the room is also displayed on the seven segment displays. The microcontroller does the above job. It receives the signals from the sensors, and this signal is operated under the control of software which is stored in ROM. Microcontroller AT89S52 continuously monitor the Infrared Receivers. When any object pass through the IR Receivers then the IR Rays falling on the receivers are obstructed. This obstruction is sensed by the Microcontroller. 6 TABLE OF CONTENTS CHAPTER NO. TITLE PAGE NO. LIST OF FIGURES 1. Block Diagram of Circuit 2. Transmission Circuit 3. Receiver Circuit 10 13 15 19 20 20 20 22 23 24 25 35 4. Infrared Sensor 5. Block Diagram of TSOP 1738 6. Application Circuit 7. Timer IC (555) 8. LTS 542 (7-Segment Display) 9. LM7805 (Voltage Regulator) 10. Relay Circuit 11. Flow Chart 12. Circuit Diagram in PCB 1. 2. INTRODUCTION BLOCK DIAGRAM DESCRIPTION 2. 1 Power Supply 2. 2 Enter and Exit Circuits 2. 3 89S52 Microcontroller 2. 4 Relay Driver Circuit 9 11 11 11 12 12 3. CIRCUIT DESCRIPTION 3. 1 Transmission Circuit 3. 2 Receiver circuit 13 13 15 7 4. 5. LIST OF COMPONENTS DESCRIPTION OF THE COMPONENTS USED 5. 1 Microcontroller AT89S52 5. 2 TSOP1738 5. 3 555 (TIMER IC) 5. 4 LTS 542 5. 5 LM7805 5. 6 Relay Circuit 16 17 17 19 20 22 23 24 6. FLOW CHART 25 7. PROGRAM 26 8. PCB FABRICATION 30 9. CONCLUSION 36 10. BIBLIOGRAPHY 37 8 INTRODUCTION Project title is ? AUTOMATIC ROOM LIGHT CONTROLLER WITH BIDIRECTIONAL VISITOR COUNTER?. The objective of this project is to make a controller based model to count number of persons visiting particular room and accordingly light up the room. Here we can use sensor and can know present number of persons. In today’s world, there is a continuous need for automatic appliances. With the increase in standard of living, there is a sense of urgency for developing circuits that would ease the complexity of life. Also if at all one wants to know the number of people present in room so as not to have congestion, this circuit proves to be helpful. 9 BLOCK DIAGRAM ENTER SENSOR SIGNAL CONDITIONING EXIT SENSOR SIGNAL CONDITIONING A T 8 9 S 5 2 RELAY DRIVER LIGHT POWER SUPPLY 7-SEGMENT DISPLAY 10 BLOCK DIAGRAM DESCRIPTION The basic block diagram of the bidirectional visitor counter with automatic light controller is shown in the above figure. Mainly this block diagram consists of the following essential blocks. 1. Power Supply 2. Entry and Exit sensor circuit 3. AT89S52 micro-controller 4. Relay driver circuit 1. Power Supply:Here we used +12V and +5V dc power supply. The main function of this block is to provide the required amount of voltage to essential circuits. +12V is given to relay driver. To get the +5V dc power supply we have used here IC 7805, which provides the +5V dc regulated power supply. 2. Enter and Exit Circuits:This is one of the main part of our project. The main intention of this block is to sense the person. For sensing the person we are using a TSOP 1738 sensor. By using this sensor and its related circuit diagram we can count the number of persons. 11 3. 9S52 Microcontroller:It is a low-power, high performance CMOS 8-bit microcontroller with 8KB of Flash Programmable and Erasable Read Only Memory (PEROM). The device is manufactured using Atmel’s high-density nonvolatile memory technology and is compatible with the MCS-51TM instruction set and pin out. The on-chip Flash allows the program memory to be reprogrammed in-system or by a conventi onal nonvolatile memory programmer. By combining a versatile 8-bit CPU with Flash on a monolithic chip, the Atmel AT89S52 is a powerful Microcontroller, which provides a highly flexible and cost effective solution for many embedded control applications. . Relay Driver Circuit:This block has the potential to drive the various controlled devices. In this block mainly we are using the transistor and the relays. One relay driver circuit we are using to control the light. Output signal from AT89S52 is given to the base of the transistor, which energizes the particular relay, because of this, appropriate device is selected and which performs its allotted function. 12 CIRCUIT DESCRIPTION There are two main parts of the circuits. 1. Transmission Circuit (Infrared LEDs) 2. Receiver Circuit (Sensors) 1. Transmission Circuit: 13 This circuit diagram shows how a 555 timer IC, configured to function as a basic astable multivibrator. The astable multivibrator generates a square wave, the period of which is determined by the circuit external to IC 555. The astable multivibrator does not require any external trigger to change the state of the output. Hence the name free running oscillator. The time during which the output is either high or low is determined by the two resistors and a capacitor which are externally connected to the 555 timer. IR Transmission circuit is used to generate the modulated 36 kHz IR signal. The IC555 in the transmitter side is to generate 36 kHz square wave. Adjust the preset in the transmitter to get a 38 kHz signal at the o/p. Then you point it over the sensor and its o/p will go low when it senses the IR signal of 38 kHz. 14 2. Receiver Circuit: Fig. 3. 4 Receiver circuit The IR transmitter will emit modulated 38 kHz IR signal and at the receiver we use TSOP1738 (Infrared Sensor). The output goes high when there is an interruption and it return back to low after the time period determined by the capacitor and resistor in the circuit i. e. around 1 second. CL100 is to trigger the IC555 which is configured as monostable multivibrator. Input is given to the Port 1 of the microcontroller. Port 0 is used for the 7-Segment display purpose. Port 2 is used for the Relay Turn On and Turn off Purpose. LTS 542 (Common Anode) is used for 7-Segment display and that time Relay will get voltage and triggered, so light will get voltage and it will turn on and when counter will be 00 and at that time Relay will be turned off. Reset button will reset the microcontroller 15 LIST OF COMPONENTS ? Microcontroller – AT89S52 ? IC – 7805 ? Sensor – TSOP 1738 (Infrared Sensor) ? Transformer – 12-0-12, 500 mA ? Preset – 4. 7K ? Disc capacitor – 104,33pF ? Reset button switch ? Rectifier diode – IN4148 ? Transistor – BC 547, 2N2222 ? 7-Segment Display 16 DESCRIPTION OF THE COMPONENTS USED 1. Microcontroller AT89S52: The AT89S52 is a low-power, high-performance CMOS 8-bit microcontroller with 8K bytes of in-system programmable Flash memory. The device is manufactured using Atmel’s high-density nonvolatile memory technology and is compatible with the Industry-standard 80C51 instruction set and pin out. The on-chip Flash allows the program memory to be reprogrammed insystem or by a conventional nonvolatile memory pro-grammar. By combining a versatile 8-bit CPU with in-system programmable Flash on a monolithic chip, the Atmel AT89S52 is a powerful microcontroller which provides a highly-flexible and cost-effective solution to many embedded control applications. The AT89S52 provides the following standard features: 8K bytes of Flash, 256 bytes of RAM, 32 I/O lines, Watchdog timer, two data pointers, three 16-bit timer/counters, a six-vector two-level interrupt architecture, a full duplex serial port, on-chip oscillator, and clock circuitry. In addition, the AT89S52 is designed with static logic for operation down to zero frequency and supports two software selectable power saving modes. The Idle Mode stops the CPU while allowing the RAM, timer/counters, serial port, and interrupt system to continue functioning. The Power-down mode saves the RAM contents but freezes the oscillator, disabling all other chip functions until the next interrupt or hardware reset. 17 FEATURES:? 8 KB Reprogrammable flash. ? 32 Programmable I/O lines. ? 16 bit Timer/Counter—3. ? 8 Interrupt sources. ? Power range: 4V – 5. 5V ? Endurance : 1000 Writes / Erase cycles ? Fully static operation: 0 Hz to 33 MHz ? Three level program memory lock ? Power off flag ? Full duplex UART serial channel ? Low power idle and power down modes ? Interrupt recovery from power down modes ? 256 KB internal RAM ? Dual data pointer 18 2. TSOP1738 (INFRARED SENSOR) Fig. Infrared Sensor Description: The TSOP17.. – Series are miniaturized receivers for infrared remote control systems. PIN diode and preamplifier are assembled on lead frame, the epoxy package is designed as IR filter. The demodulated output signal can directly be decoded by a microprocessor. TSOP17.. s the standard IR remote control receiver series, supporting all major transmission codes. Features: ? Photo detector and preamplifier in one package ? Internal filter for PCM frequency ? Improved shielding against electrical field disturbance ? TTL and CMOS compatibility ? Output active low ? Low power consumption ? High immunity against ambient light ? Continuous data transmission possible (up to 2400 bps) ? Suitable burst length . 10 cycles/burst 19 Block Diagram: Fig. Block Diagram of TSOP 173 Application Circuit: Fig. Application circuit 3) 555 (TIMER IC): Fig. Timer IC (555) 20 Description The LM555 is a highly stable device for generating accurate time delays or oscillation. Additional terminals are provided for triggering or resetting if desired. In the time delay mode of operation, the time is precisely controlled by one external resistor and capacitor. For astable operation as an oscillator, the free running frequency and duty cycle are accurately controlled with two external resistors and one capacitor. The circuit may be triggered and reset on falling waveforms, and the output circuit can source or sink up to 200mA or drive TTL circuits. Features: ? Direct replacement for SE555/NE555 ? Timing from microseconds through hours ? Operates in both astable and monostable modes ? Adjustable duty cycle ? Output can source or sink 200 mA ? Output and supply TTL compatible ? Temperature stability better than 0. 005% per  °C ? Normally on and normally off output ? Available in 8-pin MSOP package Applications: ? Precision timing ? Pulse generation ? Sequential timing 21 ? Time delay generation ? Pulse width modulation ? Pulse position modulation ? Linear ramp generator 4) LTS 542 (7-Segment Display) Description: The LTS 542 is a 0. 52 inch digit height single digit seven-segment display. This device utilizes Hi-eff. Red LED chips, which are made from GaAsP on GaP substrate, and has a red face and red segment. Fig. 7 Segment Display Features: ? Common Anode ? 0. 52 Inch Digit Height ? Continuous Uniform Segments ? Low power Requirement ? Excellent Characters Appearance ? High Brightness High Contrast ? Wide Viewing Angle 22 5) LM7805 (Voltage Regulator) Fig. Voltage Regulator Description: The KA78XX/KA78XXA series of three-terminal positive regulator are available in the TO-220/D-PAK package and with several fixed output voltages, making them useful in a wide range of applications. Each type employs internal current limiting, thermal shut down and safe operating area protection, making it essentially indestructible. If adequate heat sinking is provided, they can deliver over 1A output current. Although designed primarily as fixed voltage regulators, these devices can be used with external components to obtain adjustable voltages and currents. 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 Protection 23 6) RELAY CIRCUIT: Fig. Relay A single pole dabble throw (SPDT) relay is connected to port RB1 of the microcontroller through a driver transistor. The relay requires 12 volts at a current of around 100ma, which cannot be provided by the microcontroller. So the driver transistor is added. The relay is used to operate the external solenoid forming part of a locking device or for operating any other electrical devices. Normally the relay remains off. As soon as pin of the microcontroller goes high, the relay operates and releases. Diode D2 is the standard diode on a mechanical relay to prevent back EMF from damaging Q3 when the relay releases. 4 FLOW CHART: Fig. 4. 7 Flow Chart ? If the sensor 1 is interrupted first then the microcontroller will look for the sensor 2, and if it is interrupted then the microcontroller will 25 increment the count and switch on the relay, if it is first time interrupted. ? If the sensor 2 is interrupted first then the microcontroller will look for the sensor 1, and if it is interrupted then the microcontroller will decrement the count. ? When the last person leaves the room then counter goes to 0 and that time the relay will turn off, and light will be turned off. PROGRAM / Program to make a bidirectional visitor counter using IR sensor #include #define msec 1 unsigned int num=0; sbit dig_ctrl_4=P2^6; //declare the control pins of seven segments sbit dig_ctrl_3=P2^5; sbit dig_ctrl_2=P2^6; sbit dig_ctrl_1=P2^5; sbit relay1 = P2^0; sbit pin = P3^7; unsigned char digi_val[11]={0xFE,0x18,0x6D,0x3d,0x1B,0X37,0x77,0x1C,0xfF,0x3F}; unsigned int dig_1,dig_2,dig_3,dig_4,test=0; unsigned char dig_disp=0; sbit up=P1^0; //up pin to make counter count up sbit down=P1^1; //down pin to make counter count down void delay(int x) { char y = 200; pin = ! pin; while((x)) { 6 while((y)); } } void init() // to initialize the output pins and Timer0 { up=down=1; dig_ctrl_4 = 0; dig_ctrl_3 = 0; dig_ctrl_2 = 0; dig_ctrl_1 = 0; relay1 = 0; TMOD=0x01; TL0=0xf6; TH0=0xFf; IE=0x82; TR0=1; P0= 0x00; } void delay1() //To provide a small time delay { TMOD=0x01; TL0=0x36; TH0=0xF6; TR0=1; while(TF0==0); TR0=0; TF0=0; } void display() interrupt 1 // Function to display the digits on seven segment. For more details refer seven segment multiplexing. { TL0=0x36; TH0=0xf6; P0=0xFF; dig_ctrl_1 = dig_ctrl_3 = dig_ctrl_2 = dig_ctrl_4 = 0; dig_disp++; dig_disp=dig_disp%2; 7 switch(dig_disp) { case 0: P0= ~digi_val[dig_1]; dig_ctrl_1 = 1; break; case 1: P0= ~digi_val[dig_2]; dig_ctrl_2 = 1; break; case 2: P0= ~digi_val[dig_3]; dig_ctrl_3 = 1; break; case 3: P0= ~digi_val[dig_4]; dig_ctrl_4 = 1; break; } } void main() { unsigned int cnt=0; init(); relay1 = 0; dig_ctrl_2 = 0; dig_ctrl_1 = 0; cnt = 0; relay1 = 1; delay(100); relay1 = 0; delay(100); while(1) { 28 if(up==1) { cnt=0; delay(1000); if(down==1) { if(test0)test; if(test == 0) { relay1 = 0; } dig_2=test%10; dig_1=test/10; } } } } 29 PCB FABRICATION Printed Circuit Board (PCB) is piece of art. The performance of an electronic circuit depends on the layout and the design of PCB. A PCB mechanically supports and connects components by conductive pathways, etched from copper sheets laminated on to insulated substrate. PCB ape used to rotate electrical currents and signals through copper tracts which are firmly bonded to an insulating base. PCB Fabrication involves the following steps: 1. Drawing the layout of the PCB in the paper. The track layout of the Electronic circuit should be made in such manner that the paths are in easy routes. It is then transferred to a Mylar sheet. The sheet is then touched with black ink. 2. The solder side of the Mylar sheet is placed on the shiny side of the fiveStar sheet and is placed in a frame. Then it is exposed to sunlight with Mylar sheet facing the sunlight. 3. The exposed five- star sheet is put in Hydrogen Peroxide solution. Then it is put in hot water and shook till unexposed region becomes transparent. 4. This is put in cold water and then the rough side is stuck on to the silk screen. This is then pressed and dried well. 5. The plastic sheet of the five-star sheet is removed leaving the pattern on the screen. . A copper clad sheet is cut to the size and cleaned. This is placed under screen. 7. As it resistant ink if spread on the screen so that a pattern of tracks and a pad is obtained on a copper clad sheet. It is then dried. 8. The dried sheet is then etched using Ferric chloride solution (32Baume) till all the unwanted Copper is etched away. Swish the board to keep each fluid moving. Lift up the PCB and check whether all the unwanted Copper is removed. Etching is done by immersing the marked copper clad in Ferric Chloride solution after that the etched sheet is dried. 9. The unwanted resist ink is removed using Sodium Hydroxide solution Holes are them dried. 30 PCB PARAMETERS Copper thickness Track width Clearance Pad width Pad height Pad shape Pad hole size On board Hole size Base PCB Quality 72mil (1mm=39. 37 mils) 60mil 60mil 86mil 86mil Oval 25mil Through 0. 9mm (36mil) Paper phenolic, Hylam FRC4 SOLDERING Soldering is the process of joining metals by using lower melting point to weld or alloy with joining surface. SOLDER Solder is the joining material that melts below 427 degree connections between components. The popularly used solders are alloys of tin (Sn) and lead (Pb) that melts below the melting point of tin. Types: 1. Rosin core: 60/40 Sn/Pb solders are the most common types used for electronics assembly. These solders are available in various diameters and are most appropriate for small electronics work (0. 02’’-0. 05? dia is recommended) 31 2. Lead free: lead free solders are used as more environmental-friendly substitutes for leaded solder, but they are typically not as easy to use mainly because of their higher melting point and poorer wetting properties. 3. Silver: Silver solders are typically used for low resistance connections but they have a higher melting point and are expensive than Sn/ Pb solders. 4. Acid –core: Acid-core solders should not be used for electronics. They are intended for plumbing or non-electronics assembly work. The acid-core flux will cause corrosion of circuitry and can damage components. 5. Other special solders 😕 Various melting point eutectics: These special solders are typically used for non-electronic assembly of difficult to construct mechanical items that must be assembled in a particular sequence. Paste solders: These solders are used in the field application or in specialized manufacturing application. FLUX In order to make the surface accept the solder readily, the components terminals should be free oxides and other obstructing films. The lead should be cleaned chemically or by abrasion using blades or knives. Small amount of lead coating can be done on the portion of the leads using soldering iron. This process is called thinning. Zinc chloride or ammonium chloride separately or in combination is mostly used as fluxes. These are available in petroleum jelly as paste flux. 2 Flux medium used to remove the degree of wetting. The desirable properties of flux are:? It should provide a liquid cover over the materials and exclude air gap up to the soldering temperature. ? It should dissolve any Oxide on the metal surface. ? It should be easily replaced from the metal by the molten soldering operation ? Residue should be removable after completing soldering operation. The most common flux used in hand soldering of electronic components is rosin, a combination of mild organic acids extracted from pine tree. SOLDERING IRON It is a tool used to melt the solder and apply it at the joints in the circuit. It operates in 230V supply. The iron at the tip gets heated while few minutes. The 50W and 25W soldering irons are commonly used for soldering of electronics circuit. SOLDERING STEPS 1. Make the layout of the component in the circuit. Plug in the chord of the soldering iron the mains to get heated. 2. Straighten and clean the component leads using a blade or a knife. 3. Mount the components on the PCB by bending the leads of the components. Use nose pliers. 4. Apply flux on the joints and solder the joints. Soldering must be in minimum time to avoid dry soldering and heating up of the components. 5. Wash the residue using water and brush. 6. Solder joins should be inspected when completed to determine if they have been properly made. 33 CHARACTERISTICS OF A GOOD SOLDER JOINTS: A. Shiny surface. B. Good, smooth fillet. CHARACTERISTICS OF A POOR SOLDER JOINTS: 1. Dull or crystallized surface: This is an indicator of a cold solder joint. Cold solder joint result from moving the component after soldering has been removed, but before the solder has hardened. Cold solder joints may work at first, but will eventually fail. 2. Air pocket: Air pocket (voids) result from incomplete wetting of surface, allowing air to be in contact with the connecting metals. This will cause oxidation of the joints and eventual failure. Blow holes can occur due to vaporization of the moisture on the surface of the board and existing through the molten solder. Boards should be clean and dry. Prior to soldering. Ethanol (100%) can be used as a moisture chaser if boards are wet prior to soldering. 3. Dimples: Dimples in the surface do not always indicate a serious problem, but they should be avoided since they are precursors to voids. 4. Floaters: Black spots ? floating? in the soldering fillet should be avoided because they indicate contamination and a potential for failure as in the case of voids. These black spots usually result from overheated (burnt) Rosin or other contaminants such as burnt wire insulation. Maintaining a clean tip will help to avoid these problems. 5. Balls: A solder balls, instead of a fillet can occur if the trace was heated but the leads was not (vice versa). This prevents proper wetting of both surfaces and result in solder being attached to only one surface (component or trace) 6. Excess solder: Excess solder usage can cover up other potential problems and should be avoided. It can lead to solder bridges. In addition, spherical solder joints can result from the application of too much solder. 34 CIRCUIT DIAGRAM IN PCB 35 CONCLUSION Here by we come to the end of our project ? AUTOMATIC ROOM LIGHT CONTROLLER WITH BIDIRECTIONL VISITOR COUNTER? ? Application of this project ? For counting purposes ? For automatic room light control ? Advantages of this project ? Low cost ? Easy to use ? Implement in single door ? Future Expansion ? By using this circuit and proper power supply we can implement various applications such as fans, tube lights, etc. ? By modifying this circuit and using two relays we can achieve a task of opening and closing the door. 36 BIBLIOGRAPHY ? Reference Books ? Programming in ANSI C: E BALAGURUSAMY ? The 8051microcontroller and embedded systems: MUHAMMAD ALI MAZIDI JANICE GILLISPIE MAZIDI ? The 8051 microcontroller: KENNETH J. AYALA ? Website ? ? ? www. datasheets4u. com www. datasheetcatalog. com www. 8051. com 37