Paraplegic Wheelchair

Prototype of a wheelchair made for handicap people. It is controlled using a touchpad and an arduino board.

1. PARAPLEGIC WHEELCHAIR

INTRODUCTION

Our project is especially for those people who are physically handicapped specially
the lower half of the body. They are unable to carry out their daily activities due to
their helplessness. We have emerged out with an idea of making the paraplegic
people able to carry out their day to day chores with proper ease, making them
independent.
The touchpad is used to move smoothly, instead of applying so much mechanical
energy on the typical wheelchairs having those big round wheels .They can control
the chair using just a single touch.
Our project is just a prototype of wheelchairs, withstanding 15-20 kilograms of
weight, including a touchpad circuits as shown thereafter in this report.

2. BLOCK DIAGRAM

The main block in this block diagram is the Arduino board

1. ARDUINO :

3. The Arduino Board is the main working board and the master of the block diagram
as shown above. We need to upload program on it.
Arduino is an open source electronics prototyping platform based on flexible, easy
to use hardware and software. It’s intended for artists, designers, hobbyists and
anyone interested in creating interactive environment. Arduino can sense the
environment by receiving input from a variety of sensors and can affect its
surroundings by controlling lights, motors and others actuators. The
microcontroller on the board is programmed using Arduino Programming
Language based on wiring and the Arduino Development Environment based on
processing .Arduino projects can be stand alone or they can communicate with
software running on a computer.

2. TOUCHPAD :
Resistive touch-screen or touchpad are touch sensitive computer displays
composed of two flexible sheets coated with a resistive material and separated by
an air gap or micro dots. There are two types of metallic layers the first type is
called as Matrix in which stripped electrodes on substrates such as glass or plastic
face each other. The second type is called Analogue which consists of transparent
electrodes without any patterning facing each other.
When contact is made to the surface of touchscreen the two sheets are pressed
together on these two sheets there are horizontal and vertical lines that when
pushed together register the precise location of the touch.

4. 3. MOTOR DRIVER IC-L298 :
The L298 is an integrated monolithic circuit in a 15-lead Multiwatt and PowerS020
packages. It is a high voltage, high current dual full-bridge driver designed to
accept standard TTL logic levels and drive inductive loads such as relays,
solenoids, DC and stepping motors. Two enables or disable the device
independently of the input signals. The emitters of the lower transistor of each
bridge are connected together and the corresponding external terminal can be used
for the connection of an external sensing resistor. An additional supply input is
provided so that the logic works at a lower voltage.

5. 4. Motors:
A DC motor relies on the fact that like magnet poles repel and unlike magnetic
poles attract each other. A coil of wire with a current running through it generates
an electromagnetic field aligned with the center of the coil. A simple DC
motor typically has a stationary set of magnets in the stator and an armature with a
series of two or more windings of wire wrapped in insulated stack slots around iron
pole pieces (called stack teeth) with the ends of the wires terminating on
a commutator. The armature includes the mounting bearings that keep it in the
center of the motor and the power shaft of the motor and the commutator
connections. The winding in the armature continues to loop all the way around the
armature and uses either single or parallel conductors (wires), and can circle
several times around the stack teeth. The total amount of current sent to the coil,
the coil's size and what it's wrapped around dictate the strength of the
electromagnetic field created.

6.  60 RPM DC Motor:
Specification:
18000 RPM base motor
Shaft : 6mm
Gearbox diameter : 37 mm.
Motor Diameter : 28.5 mm
Length : 63 mm with shaft
Shaft length : 15mm
Weight : 300 gm
No-load current = 800 mA(Max),
Load current = up to 9.5 A(Max)


 10 RPM DC Motor:
Specifications:
18000 RPM base motor
Shaft : 6mm
Gearbox diameter : 37 mm.
Motor Diameter : 28.5 mm
Length : 63 mm without shaft
Shaft length : 15mm
Weight : 300 gm
No-load current = 800 mA(Max),
Load current = up to 9.5 A(Max)
BATTERIES:
A rechargeable battery, storage battery, or accumulator is a type of electrical
battery. It comprises one or more electrochemical cells, and is a type of energy
accumulator. It is known as a secondary cell because
its electrochemical reactions are electrically reversible. Rechargeable batteries
come in many different shapes and sizes, ranging from button cells to megawatt
systems connected to stabilize an electrical distribution network. Several different
combinations of chemicals are commonly used, including: lead–acid, nickel

7. cadmium (NiCd), nickel metal hydride (NiMH), lithium ion (Li-ion), and lithium
ion polymer (Li-ion polymer).

ARDUINO PROGRAM:
void setup()
{
Serial.begin(9600);
Serial.print("Start");

pinMode(6,OUTPUT);//PWM FOR FORWARD WHEELS
pinMode(9,OUTPUT);

pinMode(2,OUTPUT); //FORWARD WHEELS
pinMode(3,OUTPUT);
pinMode(4,OUTPUT);

8. pinMode(5,OUTPUT);

pinMode(10,OUTPUT);//PWM FOR BACKWARD WHEELS
pinMode(11,OUTPUT);

pinMode(7,OUTPUT);
pinMode(8,OUTPUT); //BACK WHEELS
pinMode(12,OUTPUT);
pinMode(13,OUTPUT);
}

void loop()
{
//////////////////////////////////////////////////////
pinMode(A0,OUTPUT);
pinMode(A1,INPUT);
pinMode(A2,OUTPUT);
pinMode(A3,INPUT);

digitalWrite(A0,HIGH);
digitalWrite(A2,LOW);
int x=analogRead(A1);

9. Serial.print(x);
Serial.print(" ");

pinMode(A1,OUTPUT);
pinMode(A0,INPUT);
pinMode(A3,OUTPUT);
pinMode(A2,INPUT);

digitalWrite(A1,HIGH);
digitalWrite(A3,LOW);

int y=analogRead(A0);

Serial.print(y);
Serial.println(" ");
////////////////////////////////////////////////////////

if(y>600 && x<600 && x>400) //forward
{

analogWrite(10,150);
analogWrite(11,150);
delay(500);

10. digitalWrite(7,HIGH);
digitalWrite(8,LOW);
digitalWrite(12,HIGH);
digitalWrite(13,LOW);

digitalWrite(2,LOW);
digitalWrite(3,LOW);
digitalWrite(4,LOW);
digitalWrite(5,LOW);
}

///////////////////////////////////////////////
else if(y<450 && x<600 && x>400) //reverse
{

analogWrite(10,150);
analogWrite(11,150);
delay(500);

digitalWrite(7,LOW);
digitalWrite(8,HIGH);
digitalWrite(12,LOW);

11. digitalWrite(13,HIGH);

digitalWrite(2,LOW);
digitalWrite(3,LOW);
digitalWrite(4,LOW);
digitalWrite(5,LOW);
}

/////////////////////////////////////////////
else if(x>600 && y<600 && y>450) //right
{
digitalWrite(7,LOW);
digitalWrite(8,LOW);
digitalWrite(12,LOW);
digitalWrite(13,LOW);

analogWrite(6,150);
analogWrite(9,150);
delay(500);

digitalWrite(2,LOW);
digitalWrite(3,HIGH);
digitalWrite(4,LOW);

12. digitalWrite(5,HIGH);
}
///////////////////////////////////////////////
else if(x<400 && y<600 && y>450) //left

{

digitalWrite(7,LOW);
digitalWrite(8,LOW);
digitalWrite(12,LOW);
digitalWrite(13,LOW);

analogWrite(6,150);
analogWrite(9,150);
delay(500);


digitalWrite(2,HIGH);
digitalWrite(3,LOW);
digitalWrite(4,HIGH);
digitalWrite(5,LOW);
}
////////////////////////////////////////////////////////////

13. else if(y>600 && x<400) //immediate left
{

analogWrite(10,255);
analogWrite(11,255);
digitalWrite(7,LOW);
digitalWrite(8,HIGH);
digitalWrite(12,HIGH);
digitalWrite(13,LOW);
}
////////////////////////////////////////////////////////////
else if(y>600 && x>600) //immediate right
{
analogWrite(10,255);
analogWrite(11,255);
digitalWrite(7,HIGH);
digitalWrite(8,LOW);
digitalWrite(12,LOW);
digitalWrite(13,HIGH);
}
///////////////////////////////////////////////////////////////
else
{

14. digitalWrite(7,LOW);
digitalWrite(8,LOW);
digitalWrite(12,LOW);
digitalWrite(13,LOW);

digitalWrite(2,LOW);
digitalWrite(3,LOW);
digitalWrite(4,LOW);
digitalWrite(5,LOW);
}
}