A SEMINAR PRESENTATIONON

“MINOR PROJECT”NAMED AS

PROPELLER CLOCK

Submitted to:MS. Monika SuranaMs. Anshu Toshniwal(Project Coordinators)

Submitted by:Pankaj Singh Bhadauriya (EC/09/46)Rahul Agarwal (EC/09/108)Pradeep Rathore (EC/09/45)IV Year, EC – B

Department of Electronics and Communication Engineering 

POORNIMA COLLEGE OF ENGINEERINGISI-6, RIICO INSTITUTIONAL AREA, SITAPURA, JAIPUR-302022

2012 - 2013

CONTENT : Project Selection

Propeller Clock : An Introduction

Basic Principle

Block Diagram

Circuit Diagram

Component List

Power Supply

Motor Diagram

Final Looking

Circuit Working

Advantages & Applications

PROJECT SELECTION :After doing a lot of search work and survey, we have

submitted thee synopsis as:

1. Electronic Code Lock with User Defined

Password

2. Automatic Bidirectional Visitor Counter

3. Propeller Clock

Then according to the guidance of project coordinators

and our interest we chose the “PROPELLER CLOCK” as our

minor project.

WHAT IS PROPELLER CLOCK ???

Propeller is a term associated with a circular rotating object.

As this project needs to rotate whole circuit assembly, there

must be some prime mover attached to it. So, the term

‘Propeller’.

This project using bright light emitting diodes for displaying

the analog clock on its assembly.

That’s why this project is named as “PROPELLER CLOCK”.

Basic principle behind this project:

POV (Persistence Of Vision):

This is the phenomenon which is related to vision capability

of human eye by which an after- image is thought to persist

for approximately 1/25th of a second.

So, if someone is observing the images at a rate of 25

images per second, then they appear to be continuous.

The best example of this property is the red circle we

observe when we rotate the firecracker or incense stick in

circle.

BASIC PRINCIPLE :

INTRODUCTION : In this project, our aim is to use PIC 16F84 microcontroller

to control a row of LEDs to display some images and function

it as a clock.

Due to the slow response of the human eye, we get the

impression that the lights are on all together and we can

read the display.

A limited number of LEDs are placed in a row and attached

to a rotating board.

CONTD .... :

The LEDs are turned on and off at very precise times and

places.

This gives the impression that there are several LEDs

making up a complete display.

All we can see are the lighted dots from the LEDs making a

readable display that seems to float.

Several sensors including infrared proximity sensors are

used to detect the completion of one revolution.

BLOCK DIAGRAM :

Microcontroller

LEDDisplay

IRSensor

BeamInterruptIn each

revolution

DCmotor

DC Regulated

power supply

CIRCUIT DIAGRAM :

COMPONENTS LIST :S.NO. COMPONENT NAME QUANTITY

1. PIC 16F84 12. Transformer 13. LED 84. IR LED 15. Resistor, 100 ohm 96. Resistor, 10k, 3.6k 27. Capacitor , 10uf/63V 18. Battery, 5V 49. Crystal Oscillator, 11.0592 MHz 110. Photo Diode 111. ON – OFF Switch 312. Battery, 12V 113. Rectifier 114. IC, 7805 115. Capacitor, 1000uf 1

POWER SUPPLY :

MOTOR DIAGRAM :

FINAL LOOKING :

5V GND

MOC7811

Circuit LEDs

CIRCUIT WORKING :

In this section we will emphasize on detailed overview of

each of the block

shown in previous block diagram. In every description of the

block

respective schematics and working is explained.

The propeller display consists of following blocks, as shown

in the block

diagram.

Interrupter Module

Microcontroller

LED module

DC motor

DC power supply

CONTD.... : Interrupter Module :

MOC7811 is the sensing part of the interrupter module,

while rest of the circuitry works as signal conditioning

circuit.

3 wires emerge out from the module, respectively Vcc,

Signal and Ground. Output of the module is LOW, if

interrupt occurs, otherwise it remains HIGH.

It consists of IR LED and Photodiode mounted facing each

other enclosed in plastic body.

This sensor is used to give position feedback.

CONTD.... : Microcontroller :

Requirements: -> Moderate speed

-> Ports required : 2

-> Small Sized

-> Code memory > 1kB

Component Selected: PIC 16F84

DC Motor :

Repeated scanning of the display is must for continuous vision. This task is achieved using circular rotation of the whole circuit assembly. So, we used a DC motor as the prime mover.

CONTD.... : LED Module :

LED module consisting of 8 bright LEDs are fixed in another

side of the arm of our project.

These LEDs are connected with each of the port pin of

microcontroller, with a series current limiting resistor of 100

ohm.

DC Power Supply :

For microcontroller, as well as the DC motor, a regulated DC

power supply is required. We have to provide +5V to the

microcontroller, while +12V to the motor.

It can be used to replace various public LCD screens thereby

providing a cheaper solution.

It can also be used as a stopwatch.

So, this was a brief introduction and basic functioning

phenomenon of

our project, which was named as “PROPELLER CLOCK”. Now

we are

going to show you a video, from that you will be familiar

with our project…

Lets watch out

that……..>

ADVANTAGES & APPLICATIONS :