1. WIRELESS DC MOTOR SPEED AND DIRECTION CONTROL USING RF COMMUNICATION
Project Title
WIRELESS DC MOTOR SPEED AND DIRECTION CONTROL USING RF COMMUNICATION
Under the Guidance of
Submitted by

2. ABSTRACT
The main scope of project is to control the DC motor remotely using primarily the RF mode.
The remote control besides being Omni directional has the advantage of adequate range (up to 200 meters with proper antenna).
However, the microcontroller being used for the project has latched outputs and as such one does not have to keep the buttons on remote control pressed for more than a few milliseconds, this helps prolonging the battery life for remote. 
This project uses the above principle to control the speed of the motor by varying the duty cycle of the pulse applied to it (popularly known as PWM control).

3. PROJECT BLOCK DIAGRAM
Transmitter section

4. Receiver Section

5. MICROCONTROLLER (AT89S52/AT89C51) RF Transmitter and RF Receiver
HARDWARE REQUIREMENTS
POWER SUPPLY BLOCK
MICROCONTROLLER (AT89S52/AT89C51)
RF Transmitter and RF Receiver
HT12E/HT12D
L293D
DC MOTOR
PUSH BUTTONS
BC547
LED
1N4007
RESISTOR
CAPACITOR

6. POWER SUPPLY Bridge rectifier 5v Regulator 230 V AC 50 Hz 5V DC
Filter(470µf)
12V step down
transformer

7. It is a smaller computer Has on-chip RAM, ROM, I/O ports...
MICROCONTROLLER
It is a smaller computer
Has on-chip RAM, ROM, I/O ports...
RAM
ROM
I/O Port
Timer
Serial COM Port
Microcontroller
CPU
A single chip

8. INTERNAL STRUCTURE OF A MICRO CONTROLLER-AT89S52/51
CPU
On-chip RAM
On-chip ROM for program code
4 I/O Ports
Timer 0
Serial Port
OSC
Interrupt Control
External interrupts
Timer 1
Timer/Counter
Bus Control
TxD RxD
P0 P1 P2 P3
Address/Data
Counter Inputs

9. Features of AT89S51/52 Compatible with MCS®-51 Products
8K Bytes of In-System Programmable (ISP) Flash Memory
Endurance: 10,000 Write/Erase Cycles
4.0V to 5.5V Operating Range
Fully Static Operation: 0 Hz to 33 MHz
256 x 8-bit Internal RAM
32 Programmable I/O Lines
Three 16-bit Timer/Counters
Eight Interrupt Sources
Full Duplex UART Serial Channel
Interrupt Recovery from Power-down Mode
Watchdog Timer
Dual Data Pointer

10. Pin Description

11. RF Transmitter and Receiver
RF modules are normally divided into three groups, RF transmitter module, RF receiver module and RF transceiver module
433MHz ASK transmitter and receiver is used for the remote control.
Fig : RF Transmitter

12. Features of RF Range in open space(Standard Conditions) : 100 Meters
RX Receiver Frequency : 433 MHz
RX Typical Sensitivity : 105 Dbm
RX Supply Current : 3.5 mA
RX IF Frequency : 1MHz
Low Power Consumption
Easy For Application
RX Operating Voltage : 5V
TX Frequency Range : MHz
TX Supply Voltage : 3V ~ 6V
TX Out Put Power : 4 ~ 12 Dbm
Fig RF Receiver

13. HT 12 ENCODER Operating voltage is 2.4V~12V for the HT12E.
Features
Operating voltage is 2.4V~12V for the HT12E.
Low power and high noise immunity CMOS technology
Low standby current: 0.1_A (typ.) at VDD=5V
HT12A with a 38kHz carrier for infrared transmission medium
Minimum transmission words are Four words for the HT12E
Built-in oscillator needs only 5% resistor
Data code has positive polarity
Minimal external components
HT12A/E: 18-pin DIP/20-pin SOP package

14. HT12 DECODER Features Operating voltage: 2.4V~12V.
Low power and high noise immunity CMOS technology.
Low standby current.
Capable of decoding 12 bits of information.
Binary address setting.
Address/Data number combination for HT12D: 8 address bits and 4 data bits.
Valid transmission indicator
Minimal external components
18-pin DIP, 20-pin SOP package

15. MOTOR DRIVER (L293D) Wide supply-voltage range: 4.5V to 36V
Features:
Wide supply-voltage range: 4.5V to 36V
Separate input- logic supply
Internal ESD protection
Thermal shutdown
High-Noise-Immunity input
Functional Replacements for SGS L293 and SGS L293D
Output current 1A per channel (600 mA for L293D)
Peak output current 2 A per channel (1.2 A for L293D)
Output clamp diodes for Inductive Transient suppression(L293D)

16. DESCRIPTION
L293D is a dual H-bridge motor driver integrated circuit (IC).
In its common mode of operation, two DC motors can be driven simultaneously, both in forward and reverse direction.
The motor operations of two motors can be controlled by input logic at pins 2 & 7 and 10 & 15.
Input logic 00 or 11 will stop the corresponding motor. Logic 01 and 10 will rotate it in clockwise and anticlockwise directions, respectively.
Enable pins 1 and 9 (corresponding to the two motors) must be high for motors to start operating. When an enable input is high, the associated driver gets enabled

17. DC- MOTOR
A DC motor is an electric motor that runs on direct current (DC) electricity. In any electric motor, operation is based on simple electromagnetism.
A simple 2-pole DC electric motor (here red represents a magnet or winding with a "North" polarization, while green represents a magnet or winding with a "South" polarization).
Every DC motor has six basic parts -- axle, rotor (a.k.a., armature), stator, commutator, field magnet(s), and brushes.

18. BC547 (NPN –Transistor)
The BC547 transistor is an NPN Epitaxial Silicon Transistor.
It is used in general-purpose switching and amplification BC847/BC547 series 45 V, 100 mA NPN general-purpose transistors.
The ratio of two currents (Ic/Ib) is called the DC Current Gain of the device and is given the symbol of hfe or nowadays Beta, (β).

19. The current gain from the emitter to the collector terminal, Ic/Ie, is called Alpha, (α), and is a function of the transistor itself

20. WORKING OF PROJECT
The DC motor can be remotely controlled by one transmitting unit
and a receiving unit using motors for its moment.
Push buttons are arranged and fed to MC which in turn help the DC motor to move in a direction.
HT12E Encoder which convert’s 4 bit data to serial output fed to the RF
transmitter, the same to be received by the RF receiver module the output
of which is fed to HT12D the serial decoder IC, the output of which is fed to MC
The data so received at the receiver end operates the motor through motor
driver IC L293D as required being interfaced from the Microcontroller  

21. Software Requirements
Keil an ARM Company makes C compilers, macro assemblers, real-time kernels, debuggers, simulators, integrated environments, evaluation boards, and emulators for ARM7/ARM9/Cortex-M3, XC16x/C16x/ST10, 251, and 8051 MCU families.
Compilers are programs used to convert a High Level Language to object code. Desktop compilers produce an output object code for the underlying microprocessor, but not for other microprocessors.

22. i.e the programs written in one of the HLL like ‘C’ will compile the code to run on the system for a particular processor like x86 (underlying microprocessor in the computer).
For example compilers for Dos platform is different from the Compilers for Unix platform  So if one wants to define a compiler then compiler is a program that translates source code into object code.

23. BIBILOGRAPHY
“The Microcontroller and Embedded systems” by Muhammad Ali Mazidi and Janice Gillispie Mazidi , Pearson Education.
ATMEL 89S52 Data Sheets.

24. THANKYOU