Bicycle Powered Phone Charger
Bicycle Powered Phone Charger
Bicycle Powered Phone Charger
The world is a storehouse of energy. Energy can neither be created nor be destroyed but can be
transformed from one form to another. We are wasting resources that can produce energy as though
they are limitless. If we can use the energy we waste, it would help in some way to solve the problem
of scarcity of energy, which is the major threat of the present world. Humans are able to generate
power while riding bicycles. However, this power goes to waste without any use. If we can make use
of this energy, we would be able to power many electronic devices.
Bicycles are also the main mode of transportation for many Indian villagers. Most of these villages
are without power. Power generated by pedalling can be converted from mechanical to electrical
energy by using either a dynamo or an alternator. This is where pedal powered phone chargers come
in. It allows the user to charge his phone while on the move.
The charger charges the phone based on rotation of the cycles wheels. If the user is at standstill then
the device switches over to a solar charging mechanism in which, solar cells help charge the cell
phones battery.
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ACKNOWLEDGEMENT:
On the very outset of this project, I would like to extend my sincere and heartfelt gratitude towards
my guide Mrs. B Gayathri Devi for her constant support throughout the course of this venture.
I am ineffably indebted to Mrs Pushpa for her conscientious guidance and encouragement to
accomplish this assignment.
I would also like to sincerely express my gratitude to my friend, Bhargava Venkatesh, for his timely
assistance and help through the course of the project
I am extremely thankful and express my earnest gratitude to the faculty members of electrical and
electronics department of PESIT for providing me with valuable information in our endeavour.
I would also like to show my appreciation for my HOD Dr.B Keshavan and my principal Dr K.N.B
Murthy, for providing me with the opportunity to take this task upon myself.
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TABLE OF CONTENTS
Chapter 1: Introduction
Chapter 2: Design
2.0: Block Diagram Representation
2.1: Choice of Components
2.1.1: Regulator
2.1.2: Microcontroller
2.1.3: Solar Photovoltaic Cells
2.1.4:IR Sensors
2.1.5:DC Motors
4
5
6
6
7
7
7
Chapter 3: Implementation
3.0: Bread Board View
10
Bibliography
11
Appendix
13
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CHAPTER 1
INTRODUCTION
Cycles are widely used modes of transportation. Researchers from Imperial College London and the
Public Health Foundation of India and discovered that 68.3 per cent of people in rural areas cycled
and 11.9 percent walked to their workplace, compared with 15.9 percent who cycled, and 12.5
percent who walked in urban areas. Information was collected from almost 4000 participants across a
certain area.
A lot of energy is used up in travelling. If this mechanical energy is converted to electrical energy
and appropriately utilized, it can be used to charge cell phones. The device takes higher-voltage
alternating current (AC) from an alternator, converts it to direct current (DC), and steps it down to a
safe voltage for charging your cell phone or other mobile device. The charger circuit consists of a
rectifier, a capacitor, and a voltage regulator. The rectifier contains four one-way electrical gates
called diodes which, working together, convert the charges in AC to a series of DC charge pulses.
The large capacitor connected between the DC terminals of the rectifier smooths out these pulses,
charging up when theres more energy in the system and discharging when theres less. Finally, the
voltage regulator holds the incoming DC power down at a steady 5V, which is what most cell phones
and other mobile devices are designed to accept. Without the regulator in place, the charger might
deliver more than 5V to your device, which could damage it.
This model can be replicated by utilizing two dc motors and connecting them to a regulator. The two
dc motors are used to represent the rotating wheel of the cycle and the rotating shaft of the dynamo,
along with the conversion of mechanical energy to electrical energy. The dc voltage produced is
passed into a regulator, which brings the voltage to 5V and is used to power the phone. This would
represent the prototype for the pedal power phone charger.
At standstill, the cyclist would need to revert to the solar charging unit, to power his phone.
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CHAPTER 2
DESIGN
2.0 BLOCK DIAGRAM REPRESENTATION:
We consider two cases of operation. Charging the phone when the cyclist is pedalling being the first
and the charging the phone when the cyclist is at standstill.
CASE 1: PEDALLING
DC Motor
DC Motor and
IR Sensor
Voltage
Regulator
Phone
CASE 2: STANDSTILL
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Solar Photovoltaic
Module
Voltage Regulator
Phone
2.1.2 MICROCONTROLLER:
The microcontroller is used to calculate the rate at which the motor is spinning. This is done with the
assistance of the IR sensor.
Parameters
Microcontroller
Arduino
ATMega328
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Data Bus
8 bit
Speed
16Mhz
Storage
32KB
RAM
2KB
Digital I/O
14 Channels
Analog I/O
6 Channels
IDE
Arduino v1.0.1 IDE
Language
Arduino C
Kit Cost
Rs.1200
Arduino is open source and its community support is unmatched. The arduino was chosen as it is
easier to prototype with.
2.1.3 SOLAR PHOTOVOLTAIC MODULE:
Photovoltaics is a method of generating electrical power by converting solar radiation into direct
current electricity using semiconductors that exhibit the photovoltaic effect. Photovoltaic power
generation employs solar panels composed of a number of solar cells containing a photovoltaic
material. In order to generate the required voltage we use two panels in series and the voltage
produced is regulated to 5V.
2.1.4 IR SENSORS:
An IR LED, also known as IR transmitter, is a special purpose LED that transmits infrared rays in
the range of 760 nm wavelength. They, along with IR receivers, are used as sensors in order to
determine the rotations per minute, which is proportional to the amount of voltage being generated.
2.1.5 DC MOTORS:
Two dc motors are used. A battery is used to supply the first dc motor, which models the cycle, and it
converts the electrical energy to mechanical energy. This rotates the shaft of the second dc motor,
which is to model a dynamo, and it converts mechanical energy to electrical energy.
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CHAPTER 3
IMPLEMENTATION
3.1 BREADBOARD VIEW
Following is a diagram of the breadboard view of our final circuit.
Software Used: Fritzing
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CHAPTER 4
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CHAPTER 5
FUTURE ENHANCEMENTS
This project can be extended to include functioning of the phone as a speedometer. This will be in
operation during the pedalling mode.
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This can be implemented by using a Bluetooth module and an arduino in collaboration. The arduino
would calculate the rate at which the dynamo is rotating and this will help determine the speed at
which the user is travelling.
BIBILIOGRAPHY
[1] Pedal Powered Charger by makezine
[2] L7805 Datasheet
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APPENDIX
SOURCE CODE FOR RPM CALCULATION
/********************************************************************************
PESIT EEE 6th Sem Mini Project
May 2013
PEDAL POWERED PHONE CHARGER
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1PI10EE019
********************************************************************************/
/*****************************************************************************
DECLARATIONS
******************************************************************************/
volatile
unsigned
unsigned
unsigned
unsigned
unsigned
int flag
double rpmcount;
int rpm;
long timeold;
long interruptTime;
long lastInterruptTime = 0;
long timeBetween;
= 0;
/*****************************************************************************
FUNCTION TO COMPUTE ROTATIONS PER MINUTE
******************************************************************************/
void setup()
{
Serial.begin(9600);
attachInterrupt(0, rpm_fun, RISING);
//rpmcount = 0;
rpm = 0;
//timeold = 0;
}
void loop()
{
unsigned long time = millis();
if(flag == 0){
detachInterrupt(0);
rpm = 60*(1000/timeBetween);
attachInterrupt(0, rpm_fun, RISING);
flag = 1;
}
if((time - lastInterruptTime) > 2000){
rpm = 0;
}
Serial.println(rpm);
}
void rpm_fun()
{
interruptTime = millis();
if((interruptTime - lastInterruptTime) > 20){
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timeBetween = interruptTime-lastInterruptTime;
lastInterruptTime = interruptTime;
flag = 0;
}
}
/***************END OF RPM CALCULATION FUNCTION****************/
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