The project given here controls speed and direction of DC motor using joystick. To change the direction of the motor, the supply given to motor has to be reversed and to vary DC motor speed the applied input voltage has to be varied. The PWM method is very popular method to vary DC motor speed. In this method PWM wave is applied to DC motor whose pulse width can be varied. As pulse width increases the average voltage applied to motor increases and vice versa. This means as the pulse width varies the DC motor speed also varies. In this project, we will learn How to interface a L293D based DC Motor Driver in PWM mode with AVR ATmega16 microcontroller. The PWM mode is used to control the speed of DC motors. Higher the duty cycle of the PWM signal higher is the speed of DC motor. The ATmega16 microcontroller will generate PWM signals of different duty cycle using its Timer Counter 1 and will give the PWM signal to the two enable pins of the L293D.

1. JOYSTICK BASED DC MOTOR
CONTROL
PROJECT GUIDE - Mr. Rajkumar Rajoria
TEAM MEMBERS - Vaishnavi Agrawal [0905EC131178]
Shivani Bhargava [0905EC131152]
Electronics & Comm. Engineering Dept.

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CONTENTS
1. Introduction
2. Requirements
3. Block Diagram
4. Concept of PWM
5. Joystick Operation
6. Schematic Diagram
7. Simulation
8. Sequence of Operations
9. PCB Design
10. Applications
11. Project Schedule
12. Budget
13. References

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INTRODUCTION
•This is the primary movement system for any accelerating /
de-accelerating vehicle or object.
•By this module we can control the speed of two DC motors
and its direction in X & Y axis.
•Pulse Width Modulation Technique is used to control the
speed of DC motors
• Gradual speed change in dual directions using only one
Mechanical switch/ component is not possible with
potentiometer ,hence we are using Joystick as an input
device.

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REQUIREMENTS
1. ATmega16
2. Joystick
3. Crystal Oscillator(16MHz)
4. Capacitors
5. LED
6. Resistance
7. Diodes
8. Voltage Regulator IC(7805)
9. Transformer
10. Proteus 7
11. CodeVision AVR
12. Express PCB
13. Burner
Power Supply
Software
Hardware

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BLOCK DIAGRAM
JOYSTICK
+5V
GND
8 Bit ADC
ATMEGA16MOTOR DRIVING IC
L293D
M1 M2
PWM
SIGNAL
Output
from D
Port Pin

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CONCEPT OF PULSE WIDTH MODULATION
•The PWM mode is used to control the speed of DC motors.
•Higher the duty cycle of the PWM signal higher is the speed of DC motor.
•The ATmega16 microcontroller will generate PWM signals of different duty cycle
using its Timer Counter 1 and will give the PWM signal to the two enable pins of
the L293D.
• Here, we will use the DC Motor Driver to control the speed of two DC motor .
•In this way, the microcontroller will run the motors in forward/ backward direction
with different speeds.
Example:-
Analog input=1.25 V
Digital output= 256 (in 10 Bit ADC)
So,
Ton=256 ms
Toff= 1024-256=768 ms
Simply, we are controlling the average value(DC value) of output waveform.

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JOYSTICK OPERATION
•We are using a joystick to control speed as
well as direction of DC motor.
•When joystick is at centre position the motor
is rest.
•When joystick is moved forward or backward
the motor rotates forward and reverse.
•Also the motor speed increases when joystick is
moved further forward or reverse.
•It rotates motor as well as varies its speed as joystick is
moved.

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SCHEMATIC DIAGRAM

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SIMULATION

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SEQUENCE OF OPERATIONS
Joystick
Movement
8 Bit ADC
Checking for required speed
wrt obtained digital value
Motor Driving IC L293D
Motor Rotation in Desired
direction
Change in
analog input=?
STOP
Analog Input
Input not equals to zero Input=0
Digital O/P
PWM Signal
Enable Signal
YES NO
MICROCONTROLLER

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PCB DESIGN

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•Remote controlled toys like RC (remote controlled) plane,
helicopter, boat, car etc
•Joystick controlled video camera crane
•Industrial Jog controller
•Robotic arm or robotic vehicle
•Surveillance camera controller
•Joystick controlled Wheel Chair (Major Project)
APPLICATIONS
Joystick control for DC motor is used in many different
applications like -

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PROJECT SCHEDULE
TASK STATUS
•Block Diagram Completed
•Understanding Concepts Completed
•Schematic Diagram Completed
•Simulation Completed
•PCB Designing Completed
•Fabrication of Board Left to do
•Testing & Troubleshooting Left to do
•Improvisations In Major Project

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References..
•Avr Microcontroller and Embedded systems by Muhammad Ali Mazidi
•Op-amps & linear integrated circuit techmology by Gayakward
•Alldatasheet.com
•www.avrfreaks.net
•www.extremeelectronics.co.in
•www.Ablab.in
•www.engineersgarage.com
•www.instructables.com
BUDGET
•Estimated Project Cost = Rs. 300 (excluding the cost of motors)

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THANK YOU