Vehicle Speed Control System Using Rf Communication 1i3438

VEHICLE SPEED CONTROL SYSTEM USING RF COMMUNICATION

Guide Ms. SHALLY. K 1

Group MAHESH .N ANUBIN VISHNU GLADSTON GEORGE KRISHNAPRASAD .M.U

ABTRACT  To avoid accidents , it is necessary to alert the driver and to control the speed of vehicle automatically.  This project is developed based on EMBEDDED and RF Technology.  Every zone like school, highway and etc may have a transmitter tag to transmit the zone information by RF signal and a RF receiver in the vehicle to receive information  When a vehicle enters a Danger Zone then the signal will be detected by the Rx which was transmitted by the Tx placed in the Zone.  The Signal received will be decoded by the microcontroller and alert the driver through a LCD Screen.  According to signal received by Microcontroller controls the DC Motor Speed after a few seconds from the time it received the signal .  An actuator control the throttle of the vehicle.. 2

CURRENT TECHNOLOGIES  

Sign board displays Speed breakers

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OBJECTIVE To control the speed of a moving vehicle according signal received by the receiver from transmitter. The Main Components of Project • Microcontroller • Vehicle or Robot • DC Motors, to run the Vehicle • RF Transmitter • RF Receiver • LCD, to display the status of Vehicle and alert about the ZONE. • Power Supply

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CIRCUIT DIAGRAM

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RF TRASMITTER MODULE

RF RECIEVER MODULE

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POWER SUPPLY  Provide a constant 5V of DC supply from a 230V of AC supply.  This 5V DC will acts as power to different standard circuits. It mainly uses 3 devices 1. Bridge wave rectifier 2. Voltage regulator

BRIDGE WAVE RECTIFIER  Converts the whole of the input waveform to one of constant polarity (positive or negative) at its output.  Converts both polarities of the input waveform to DC (direct current) is more efficient.  Center tapped transformer (9-0-9) is used. 7

VOLTAGE REGULATOR  This will connect at the output of rectifier to get constant Dc supply instead

of ripple voltages. It mainly consists of 3 pins 1. Input 2. Output 3. Ground  The capacitor C2 is used to get thee ripple voltage as input to regulator instead of full positive cycles.

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MICRO CONTROLLER • The 89C51 is a low cost Micro controller from either ATMEL or PHILIPS. • It has a 40-pin configuration • Other components are interfaced to its ports. • The entire function of the CLIP device is under the control of Micro controller. • The Microcontroller takes input from the external sources and routes them to the appropriate devices as programmed in it. FEATURES  89C51 Central Processing Unit Speedup to 33 MHz  RAM expandable externally up to 64 Kbytes  ROM expandable externally up to 64 Kbytes  Four interrupt priority levels  Six interrupt sources  Four 8-bit input output ports  Three 16-bit timers/counters T0, T1and additional T2  Programmable clock out  Second DPTR  Asynchronous port reset  Power control modes -Clock can be stopped and resumed -Idle mode -Power down mode  128bytes of internal RAM memory  4KB of internal Rom memory

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PIN CONFIGURATION:

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MAX 232  The RS 232 is not compatible with micro controllers, so a line driver converts the RS 232's signals to TTL voltage levels.  It is a 16 pin DIP package.  The MAX232 is a dual driver/receiver  Includes a capacitive voltage generator to supply TIA/EIA-232-F voltage levels from a single 5-V supply.  Receiver converts TIA/EIA-232-F inputs to 5-V TTL/CMOS levels.  Receivers have a typical threshold of 1.3 V, a typical hysteresis of 0.5 V, and can accept ±30-V inputs.  Each driver converts TTL/CMOS input levels into TIA/EIA-232-F levels.

Figure

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TLP434A ASK RF Transmitter Module General Description:  TLP434A is

an Ultra Small Transmitter manufactured by Laipac Technology, Inc. This transmitter transmits RF signals upon reception of digital serial data from its Data In  It operates between 2.0-12V and uses the Amplitude Shift Keying modulation.  Pin 4 of this transmitter can be connected directly to an appropriate antenna via a 50P resister in order to provide a power output of 14 dBm at 5V operation.  This project used the 433.92 MHz version of the transmitter. Stature:

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HT12E 212 series Encoder General Description:  The HT12E encoder is a CMOS IC built especially for remote control system applications. It is capable of encoding 8 bits of address (A0-A7) and 4 bits of data (AD8-AD11) information.  Each address/data input can be set to one of the two logic states, 0 or 1.  Upon reception of transmit enable (TE-active low), the programmed address/data are transmitted together with the header bits via an RF medium. Features:  2.4-12V Operation  Low power, high noise immunity CMOS technology  Low standby current of < 1μA at 5V supply  Built-in oscillator with only a 5% resister  Minimal external components

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Pin Configuration

RLP434A ASK RF Receiver Module General Description:  RPL434A is a Surface Acoustic Wave (SAW) based receiver, which receives ASK modulated RF signals and outputs the serial format of data which were embedded in the received signal via its Digital data out (pin 2).  It operates between 3.3S to 6.0V and also has an analog output (linear out) for received signal testing purposes this project used  The 433.92 MHz version of the receiver.

Stature:

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HT12D 212 Series Decoder General Description:  The HT12D is a decoder IC made especially to pair with the HT12E encoder.  It is a CMOS IC made for remote control system applications.  The decoder is capable of decoding 8 bits of address (A0-A7) and 4 bits of data (AD8-AD11) information.  Like the encoder, this decoder’s address pins can be set to logic low by grounding and set to logic high by either connecting the pins to +5V  The decoder receives serial addresses and data from a programmed encoder transmitted by a carrier using RF or an IR transmission medium

Features:  2.4 – 12V operation  Low power and high noise immunity CMOS technology  Low standby current of < 1μA at 5V supply  Binary address setting  Three times of received address checking  Built-in oscillator with only a 5% resistor  Valid transmission indicator  Easy interface with a RF or IR transmission medium  Minimal external components

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DC MOTOR  Really a multi-phase AC motor, but can control it like a DC motor using trick  Like a DC motor turned inside out, commutation done on windings  Medium construction complexity, multiple fields, delicate magnets  High reliability (no brush wear), even at very high achievable speeds  High efficiency  Driven by multi-phase Inverter controllers  Sensorless speed control possible  Higher total system cost than for DC motors

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L293D DRIVER  Because of induction of the windings, power requirements, and temperature management, some glue circuitry is necessary between digital controllers and motor.  In our project to interface DC motor with microcontroller we use L293D driver.L293D are quadruple high-current half-H drivers.  The L293D is designed to provide bidirectional drive currents of up to 600-mA at voltages from 4.5 V to 36 V.  When an enable input is high, the associated drivers are enabled, and their outputs are active in phase with their inputs. When the enable input is low, those drivers are disabled, and their outputs are off and in the high-impedance state.

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LIQUID CRYSTAL DISPLAY [LCD]  The display contains two internal byte-wide s, one for commands (instructions) (RS=0) and the second for characters (data) to be displayed (RS=1).  It also contains a -programmed RAM area that can be programmed to generate any desired character that can be formed using a dot matrix.  The display takes varying amounts of time to accomplish the functions as listed. LCD bit 7 is monitored for logic high (busy) to ensure the display is overwritten.  A slightly more complicated LCD display (4 lines*40 characters) is currently being used in medical diagnostic systems to run a very similar program.

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Pins Description 1 Ground 2 Vcc 3 Contrast Voltage 4 "R/S“ Instruction(0)/data(1) Select 5 "R/W" Read(1)/Write(0) LCD s 6 "E" Clock 7 -14 Data I/O Pins 8 A(anode) back light power supply 5V 9 K(cathode) back light power supply GND

Gnd

+5

1

2

Vd

A

K

3

15

16

16x2 Liquid Crystal Display

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5

6

7

8

9

10

11

12 13

14

19 RS

R/W En

D0

D1 D2

D3

D4

D5

D6

D7

THANK YOU...

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