RF Based Remote Control Robot

INTRODUCTION:

This project controls a remote robot through RF. The ordinary 433mhz

RF modules are used in this project. AT89C51 microcontroller is used in

this project. It is also an 8051 microcontroller. You can burn the same

hex file into any 8051 microcontroller.

You can make the robot to move front and back, turn left and right. Also

you can control the speed of the robot from the remote. The RF wireless

technique is used for obtaining the control of the motor using

microcontroller.

Circuit Diagram:

RF TRANSMITTER:

RF RECEIVER:

POWER SUPPLY AND MOTOR DRIVING CIRCUIT

DIAGRAM:

BLOCK DIAGRAM DESCRIPTION:

I] Microcontroller: 1. PORT 0: (PIN NO. 39- PIN NO. 32): P0.0 P0.7 of

the micro controller is connected to the motor driver circuit.

2. Pin no. 9 is RESET pin, which is connected to the reset circuit.

3. Pin no. 9 and 10 of ADC are serial data line (SDA) and serial clock line

(SCL) respectively. Both are connected to a positive supply through a

pull-up resistor. These pins are connected to the P1.6 & P1.7 of the

micro controller.

II] DRIVER CIRCUIT:

1. The L293 and L293D are quadruple high-current drivers.TheL293is

designed to provide bidirectional drive currents of up to 1 A at voltages

from 4.5 V to 36 V. The L293D is designed to provide bidirectional drive

currents of up to 600-mA at voltages from 4.5 V to 36 V. Both devices

are designed to drive inductive loads such as relays, solenoids, dc and

bipolar stepping motors, as well as other high-current/high-voltage loads

in positive-supply applications.

2. All inputs are TTL compatible. Each output is a complete totem-pole

drive circuit, with a Darlington transistor sink and a pseudo-Darlington

source. Drivers are enabled in pairs, with drivers 1 and 2 enabled by

1,2EN and drivers 3 and 4 enabled by 3,4EN.

3. When an enable input is high, the associated drivers are enabled and

their outputs are active and 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. With the proper data inputs, each pair of

drivers forms a full-H reversible drive suitable for solenoid or motor

applications.

4. A Vcc1 terminal, separate from Vcc2, is provided for the logic inputs

to minimize device power dissipation.

III] TRANSMITTER CIRCUIT:

KEYPAD

This unit consists of four switches which are used for controlling the

robot.

ENCODER

The encoder IC used in the circuit is HT12E. It converts the parallel data,

which is inputted with the help of switches, into serial data. It is an

active low IC.

TRANSMITTER MODULE

This module transmits the data from the encoder at a frequency of

434MHz. Efficient transmission can take place within a range of 60

meters with the help of an antenna. Amplitude Shift keying modulation

is used for transmission of data.

IV] RECEIVER CIRCUIT:

RECEIVER MODULE

The receiver module consists of two sections; reception and

demodulation. The reception module receives the data transmitted from

the transmitter module. The other unit demodulates the received data

and separates the wanted data, which is then sent to the decoder.

DECODER

The decoder IC used is HT12D. It converts the serial data, from the

receiver, into parallel data. It is an active low IC.

OPERATION OF ROBOT:

1. Initially we will assume the rest position of entire system.

2. A signal is sent to the microcontroller which is burnt with program

which tells what operation is to be performed at this stage.

3. For understanding operation, let us rename the two motors used here.

Let the name of gantry motor be M1 and that for end effecter motor is

M2.

4. Now forward key is pressed, it moves motor M1 in say clockwise

direction and m2 in anti-clock direction for a time till we press forward

key and robot moves forward direction..

5. As left key is pressed there, M1 stops and now motor M2 is started in

say anti-clockwise direction and robot turns in left direction.

6. As M2 gets off, motor M1 is moved again in clockwise direction till the

time right key is pressed and robot turns in right direction.

7. Now if backward key is pressed, it moves motor M1 in say anti-

clockwise direction and m2 in clockwise direction for a time till we press

backward key and robot moves in backward direction.

APPLICATIONS:

1. It can be used in Production industry.

2. In mass production.

3. In Automobile Industry.

FUTURE SCOPE:

1. Bottle filling Plant uses as pick and place robot

2.It is used further as wireless controlled mine detecting robot in

military.