Dtmf Based Dc Motor Speed And Direction Control 726p1l

DTMF BASED SPEED AND DIRECTION CONTROL OF DC MOTOR The main aim of the project is to design a versatile device that can control DC motor by using DTMF technology of wireless communication. This device can be used to control the speed and direction of the DC motor. In manufacturing industries like plastic, textile, chemical & pharmaceuticals speed control of DC motors is important for efficient

and

consistent

production.

Depending upon the requirements & applications, the motor may be huge or small.Various DC motor drivers are available for speed control of these motors. There are several methods for controlling the speed of DC motors. One simple method is to add series resistance using rheostat. As considerable power is consumed in the rheostat, this method is not economical. As the method is to use a series switch that can be closed/open rapidly. This type of control is termed as chopper control. Here we use a PWM based chopper that smoothly control the speed of DC motor. In this project we use DTMF generator (mobile phone) and the receiver circuit .Mobile phone generate DTMF tones which is received by the another phone which feed the DTMF data to the DTMF decoder IC 8870 which produce the four digit binary which is further feed to demultiplexer (4 to 16 line decoder).This project is designed in such a way that a DTMF will be interfaced to the controller through port interface along with a DC motor through voltage driver IC L293D.The microcontroller will be programmed in such a way that some predefined messages will be assigned to the controller for controlling the speed and direction of the DC motor. When ever the wants to control the motor, he has to send predefined messages to vary the speed and direction of the motor to the modem. When the modem receives data, it will intimate the

same to the microcontroller. Now, it is the job of the controller performs the predefined task of rotating the motor clockwise, anticlockwise and increasing, decreasing the speed of the dc motor in accordance with the message received from the modem. A 16X2 LCD will be interfaced to the controller to display the status of the DC motor. This project uses regulated 5V, 500mA power supply. 7805 three terminal voltage regulator is used for voltage regulation. Full wave bridge rectifier is used to rectify the ac output of secondary of 230/12V step down transformer. POWER SUPPLY

Step Down Transformer 

BLOCKDIAGRAM

Bridge Rectifier

Filter Circuit

Regulator

section

LCD DISPLAY POWER SUPPLY

DTMF DECODER

8051 MICROCONTROLL ER

L 2 9 3 d

RESET CKT

OSCILLATO R CKT

LIST OF COMPONENTS :-

MOTOR1

1. 230V-12V STEP DOWN Transformer 2. Bridge Rectifier 3. 1000 uf Capacitor 4. 100 uf Capacitor 5. 7805 Voltage Regulator IC 6. 11.0592 MHz crystal 7. 33 pf Capacitors (2 Nos.) 8. 8.2k resistor 9. 10uf Capacitor 10.

Push to ON switch

11.

5 mm LEDs

12.

AT89S52 Controller

13.

16*2 LCD

14.

DC Motor

15.

L293 Motor Driver IC

16.

DTMF Decoder