This comprises of compact yet detailed description about basic robotics. It gives description about different components that make up a robot and gives an idea on how to become advanced in robotics with an easy, user-friendly start.
1. A basic guide to a
technical journey……
A COMPILATION COMPRISING OF BASIC KNOWLEDGE ON ROBOTICS..
2. What do we first imagine to hear of
robotics ?
Is it chitti or iron man or some other action hero . It is one which
may talk ,walk , laugh and remind us of one of our favourite
heroes like the Terminator.
Yes they too soon may be there in existence with advancing
technology and researches.
They fascinate us ,climb up to our nerves but it too started with a
small step which we are going to discuss.
Let’s start with the basics of robotics and help you make a real
manually controlled car.
3. What we need ?
How to get started ?
Here is the answer .
As all the electronic components which we come across can be
broadly divided to be made up of a few categories . We are going to
discuss the same.
Before this you need to have a basic knowledge about the small
articles which we are going to use for our endeavor.
Let’s discuss the components and branches you need to emphasize
upon to make by yourself a self controlled car.
4. These are the individual broad fields in
the field of robotics.
LOCOMOTION
Power and locomotion
comprises the mechanical
design (the first steps :P)
POWER
SOURCE
SENSORS
These in company of
control system makes
the user friendly
interface for execution .
CONTROL
SYSTEM
5. PARTS OF MOBILE ROBOT TO
DISCUSS :
POWER SOURCE
LOCOMOTION SYSTEM
RECTIFIER CIRCUIT
SENSORS
H- BRIDGE
COMPARATORS
SWITCHES
ASSEMBLING
6. THE POWER SYSTEM
Without food as none can work same applies to the working live structures
we make.
In India , the main power which is available is 220V at 50 Hz. But most of the
components which are easily available and are used, are designed to have
lesser rating of around 12 V . They are D. C. components .
This problem can be sorted by use of :
1 • A battery of required rating .
2 • An Adapter
3 • A rectifier circuit
7. COMPONENTS TO BE USED.
TRANSFORMER
• Increase voltage of generator’s
output and adjusts voltage to a
usable level.
Transmit high power at low current
PRINTED CIRCUIT BOARDs
A printed circuit board, or PCB, is
used to mechanically support and
electrically connect electronic
components using conductive
pathways and tracks.
8. ADAPTER
It converts A.C. supply to a D.C. supply
It is used in video games, speaker etc.
It has internal transformer in-built.
SOLDER
This is the binding solution to
electronic components.
It is used to design our own circuit
and bind wires together.
9. RELIMATES
These are wires with special
attachments at the end enabling
easy switching mechanism.
DIODES
These are bidirectional components
meant to act as valves to the
direction of flow current.
10. CAPACITORS
This is a charge storage which
stores electrical energy and
discharges it slowly.
Integrated circuits
These are designed for specific
tasks and may function from
smoothening the pulsating waves
to acting as the fundamental part.
11. SENSORS (the feedback mechanism)
These are the sensory organs of the robots.
With advancing technology and researches robots too possess the power of senses .
VARIOUS APPLICATIONS OF SENSORS.
Sensor interfacing:
It’s direct application may be seen in line or wall following robots. They are a
link between us and bots as they act as an interface.
Acts as a trusted safeguard
It is used in fire alarms, parking sensors in vehicles etc.
It is used in Xbox series and is a major component of artificial intelligence in
robotics.
12. 1. Their eyes
As we have eyes robots too have a vision mechanism in which combination of LDR and
LEDs form the most basic system. They even find application in image processing.
Light Dependent Resistors
It’s resistance depends upon the
intensity of light and it’s made of CdS
.
Light Emitting Diodes
This is used to give a visible response
of the bot to the stimuli to the user.
13. 2. LISTENING and SPEAKING
The sound receptors in combination with speaking mechanism is an essential field in
of artificial intelligence. Besides today this is found in almost every mobile. It’s the
speaking animals that imitate us and is used as a fun tool in almost every mobile.
It’s most common use may be seen in speech recognitions sensors in computers and
mobiles.
14. 3. NOSE
The electronic nose was developed in order to mimic human olfaction that
functions as a non- separative mechanism: i.e. an odour / flavor is perceived as a
global fingerprint.
Electronic noses include three major parts: a sample delivery system, a detection
system and a computing system.
And who is going to forget the Google nose though it was a prank.
15. THE LOCOMOTION SYSTEM
In the robotics world we come across a lot new mechanisms meant for
different types of venture. Similarly in locomotion as well a lot new
mechanisms have been invented depending upon our need like the ones in
the upcoming slides.
Basically we’ll be dealing with differential drive which is one of the most
common and simpler driving mechanism.
And at the end , creativity is what
brings in a visually appealing special
touch to it.
16. 1. DIFFERENTIAL
DRIVE
This is the most common
drive used for manually
controlled bots.
It comprises of chasse having
wheels and motor connected
with a control box ( which is
an organized assembly of
switches, wires )
It enables your bot to move
forward , backward ,take left
or right turns and even zero
radius turns.
17. 2. Skid Steer Drive
It is used mostly in tracked
machines e.g. tanks.
The left and right wheels are
driven independently.
Multiple drive wheels on each
side give increased traction.
This effect enables it to have
better control .
Finds application in some
four /six wheeled robots.
18. 3. CAR TYPE
DRIVE
It is characterized by a pair of
driving wheels and a separate
pair of steering wheels.
The turning mechanism must be
accurately controlled .
He system is Non- Holonomic
hence path planning is extremely
difficult as well as in accurate
There is no direct directional
actuator.
19. 4. ARTICULATED
DRIVE
An articulated robot is one
which uses rotary joints to
access its work space.
Usually the joints are
arranged in a “chain”, so that
one joint supports another
further in the chain.
These are in great use in
industrial robots from steel
industries to bakeries.
20. 5. PIVOT DRIVE
It is composed of a four
wheeled chassis and a platform
that can be raised or lowered .
The wheels are driven by a
motor for translation motion in
a straight line
For rotation one motor is
needed to lower/raise
the platform & another to
rotate the chassis around
the platform
This system can guarantee
perfect straight line motion as
well as accurate in – place
turns to a desired heading
21. 6. SYNCRONOUS
DRIVE
These function same as
they sound . This is an
assembly of drive belts,
steer belts, steering and
driving motors.
These together work in a
synchronous manner to
enable movement in
desired direction.
This is quite a complex
system.
22. 7. DUAL
DIFFERENTIAL
DRIVE
We use two differentials
because the excess force
from one differential
automatically feeds into the
2nd diff, and therefore we
have a mechanical guarantee
of straight-line motion.
These are used in making
stronger robots which may
work well even on rough
terrains.
23. THE H-BRIDGE
An H bridge is an electronic
circuit that enables a voltage
to be applied across a load in
either direction.
These circuits are often used
in robotics and other
applications to allow DC
motors to run forwards and
backwards.
H bridges are available
as integrated circuits, or can
be built from discrete
components
24. COMPARATORS
These are not sensors.
These are meant for analog
to digital conversion.
It is the main component
which makes the input data
as sensed by the bot be
electrically judged.
They are available in
different models based on the
need.
These find wide applications
in embedded system of
robotics.
25. THE RECTIFIER CIRCUIT
Rectifiers are combination of
diodes ,capacitors, ICs ,
transformer in such a way that
it may convert A.C. current
into D.C. .
It works as one way valve
allowing current to pass
through only one direction.
The output wave form is a
pulsating dc wave which after
passing through capacitors
and ICs turn into a usable D.C.
source.
26. Components needed
1 PCB
4 x diodes
1 x 1000μF Electrolytic
Capacitor 25 V
1 x IC7812
Soldering rod and wire
2 pin Relimates
Transformer 12V
Plug connected to a long
strand of wire
Single/ Multi stranded wire
2 x 12V D.C. motors of 100rpm
2 x normal wheels
1x caster wheel
27. SWITCHES
As clear from the name it’s the
key which turns our bot to
power.
It even facilates us to have
multiple controlling methods.
Here to make a differential drive
we need a two way switch with
the following arrangement of
wire.
This gives us a two way control
The middle parts are connected
to power source.
While the wires coming from the
ends are connected to the motors
as shown in the figure.
28. ASSEMBLING THE DIFFERENT PARTS.
Once the rectifier circuit is made
and the switch is connected to the
motors , we can see the model
working but we need a strong
framework or chasse.
The chasse comprises of a solid
base of wood or metal having the
motors and wheels placed in
position.
You may use a caster wheel in front
to balance it.
Once done we may switch on the
power supply and see our mobile
manually controlled differential
drive working.
30. CONCLUSION
This is just the starting. A new era is waiting for us
though the exposure is quite less we may see the impact which they have
made upon us . Robotics has a global platform in world level
competitions as well like Robosoccer and FIRA . You may find them in
almost every field and soon it will be an integral part of life.
Have fun with
your differential
drives :D