Friends, Welcome to this course on robotics.
I will be giving the introduction this is
the first lecture in this course and in this
lecture I will give you an overview of what
the area of robotics is and in the subsequent
part of the course we will go through the
way more details of this particular area.
So let me begin without many preliminaries
you directly go into the subject of robotics
by giving you details beginning with what
we call as automation.
There are two types of, one is hollow domination
this has been there for along long time most
of you are familiar with it both at home and
in the industry or elsewhere at work familiar
examples are swinging machines washing machines
electric irons these are all forms of automation
these are what are known as hard automation.
Many of these forms in the sense that you
cannot do much of a change over from one particular
type of work that the automatic machine does
to another type of work that you desire it
cannot handle product design variation the
sort of automation on the shop floor if there
are changes in the design of the product this
sort of automation cannot handle but it has
served as well for several years for example,
in a you have these automatic devices in a
lathe you have these in a shape all.
These served us very well subsequently people
came out with what is known as adjustable
automation you want to adjust the stitch length
in your sealing machine there are some adjustments
which are provided and you could adjust the
stitch length similarly you could adjust the
pitch of the screw you are turning on your
lathe and so on these are what are known as
adjustable devices which have been used after
when once people thought a variety of products.
But of the same nature subsequently came what
is known as gram below automation though it
is not very clear as to when this emerge this
began particularly with the arrival of computers
when people started reprogramming machines
to do a variety of tasks and then we have
come to the highest level today what we call
as autonomous devices this is a robots belong
to this class of autonomous devices and perhaps
a very good example of what can we achieve
if we combine.
The power of the molecular processor with
conventional automation systems and arrive
at very powerful systems the number of systems
which are available to you in this class today
are enormous it is very difficult to describe
or list down what are the various systems
which fall into this class of highly programmable
and autonomous systems.
These autonomous systems are they in load
with lesson waking capability and that’s
a very important thing you would like the
machine itself to take addition rather than
human being continuously interfering and resetting
or changing whatever it is if there is a fault
the machine itself detects and corrects itself
so we're slowly reached this high-level of
automation and we are tending towards living
beings you know animals have such a degree
of autonomy.
When they move around they see food they move
towards it they sense the results of food
or a threat through several ways through site
through smell and so on and they react to
the environment and do what they desire or
what is best for them at the given moment
perhaps among the most autonomous devices
or autonomous capabilities process they are
possessed by human beings there is the most
advanced in terms of autonomous capabilities
we think and we react and we can change our
actions we can plan new actions this is the
level of autonomy.
Which most of us encounter the well as the
robot fall into this many people seem to think
that robots are like human beings is not really
so we can develop machines which can be autonomous
like humans and machines but do not reach
the same level of autonomy this is because
there has been tremendous development in digital
electronics and a lot of development in sensors
all these put together as the marriage of
these devices together have made it possible
for us to now come out with autonomous devices
which have many time called robots there is
no definite this definition of robots.
I shall now show you a short clip to indicate
to you how much of what you call that how
much is possible autonomy is possible when
we have a marriage between electronic systems
and mechanical systems let's have a look at
this particular clip here is a two-wheel machine
which is balancing itself this has been built
by an IIT student and yeah this particular
machine has been using gyroscope so in order
to balance itself.
What is the utility of such systems such an
animal systems can be used to undertake hazardous
tasks you know painting on the shop floor
is every hazardous toss because you’re handling
toxic material and it is indeed yes to the
health of workers Welding is a hazardous task
and also welding is a difficult task the human
being if he has to weld two pipes together
sitting on one side he has to weld all around
the pipe whereas he is able to see only one
side of the pipe then loading and unloading
jobs from a press or from alathehe is a tedious
repetitive task.
This is one more place where robots come in
and can handle with ease assembly operations
for example when you assemble a chip you have
a very fine you wafer silicon wafer to which
you have to solder very fine wires lot of
precision is required it’s not so easy to
do because human beings cannot handle such
very precise tasks and that's where the robots
come such tasks will handle by rewards from
his consistent quality that's a very important
reason why robots are being increasingly used.
Second thing is you could reprogram the robot
if there is any change in the design of the
product for example if you are welding or
if you are solar in 50 leads in a chip and
the next step requires say maybe 30 to only
then the robot can be reprogrammed to sold
as 32 yet another reason for our use of robots
is safety when they are handling dangerous
material chemicals bio chemicals and nuclear
material safety is paramount and robots can
handle this material with ease with smooth
operations and repetitively without fatigue.
And so safety is promoted I have already spoken
to you about handling of fragile and mini
pie miniature parts fragile parts like wells
of Medicine these require careful handling
and that's one more place where robots come
into the picture and can do the tasks with
much ease.
Further we must have all heard of exploration
of planets like Mars and all other you know
like the moon here we need devices to move
around gather samples you know tests and so
on when you want to operate in such are mote
areas it is very easy to use robots and undertake
the task even on for terrestrial applications
they have been recently use of robots for
exploring volcanoes for exploring remote heights
in an inaccessible places.
In mountain ranges all these have been done
by robots or underneath the sea that is another
place where you all familiar with the titanic
and how the wreckage of the Titanic was unveiled
by an underwater robot okay, now we have seen
all these things.
Let us now go to a few of these whatever I
have mentioned such as I mention here I show
you a picture of it robot painting a car the
car leasing on the conveyor the car does not
stop for the reward to paint it the conveyor
moves at a very slow speed and the robot keeps
painting it you get uniform coat and all the
cars on the conveyor because the robot has
been properly programmed it repeats the same
thing over and over again infinitely okay
so that's one of the reasons why robots are
used in order to get uniform quality and good
quality let's see a picture of a painting
robot.
You can see the painting robot painting a
car here notice that these painting robots
have a high degree of flexibility in the sense
that they can maneuver inside through the
window of the car they can maneuvering and
paint the ceiling of we are the roof of the
interior of the car these things can be done
these robots can do it with ease a man if
he is supposed to worker who is required to
do this will have to carry a heavy painting
gun.
We have to mask himself to keep the toxic
gases out of his breath and there is always
the hazards that there would be afire now
painting robots are special in the sense that
they should be able to ensure that no fire
breaks out when they’re acting what is the
status today of these robots there are one
alone as industrial robots.
There is one like the painting robot you see
there are robots similarly in industry which
unload and unload what are known as press
these are very hazardous tasks in a press
when a sheet of metal is introduced there
have been many accidents where the workers
fingers have been injured by the moving ram
of the press which sometimes comes in the
worker forgets to remove his fingers in time
from the loading point and gets them crushed.
There are medical robots which help a surgeon
undertake intricate surgery there are mobile
robots which allow you to go in survey various
planets remote areas in nuclear power plants
or in chemical power plants inaccessible areas
these could be wheeled or leg wheeled robots
can go wherever there is a smooth surface
or an incline but also on off the road very
elect robot on the other hand can step over
obstacles.
Wherever, a human can go the legs are what
can go there are many places all you have
to do is imagine that wherever a horse or
a goat or a human can go elect robot can theoretically
work them where people are still trying to
build devices which will approach that level
of confidence and performance people also
started many scientists began coming out with
what are known as a hopping and running robot.
There are robotic aircraft you must have read
about these where these aircraft without any
pilots were inside with a enemy trajectory
and you know guide the land armies towards
the enemies of fortifications these have also
been used in rescue operations to spot people
who are trapped during earthquakes and other
places these robots have been used these are
all autonomous they keep flying around and
when they using cameras onboard people can
direct the reward towards the robotic aircraft
towards.
That are get there are also robotic submarines
of course robotic toys are there they have
become very popular you find them almost in
every shop now there are also robots for entertainment
little robot we will show you one as we go
along which are banning is to the elderly
and entertain them one of the most important
tasks at home and in industry is cleaning
there are robots for clean this is just as
an example of a few applications of robots
if you were to really ask me I would say there
are much more number of applications possible
today through this marriage of mechanical
engineering electronics Computer Sciences
artificial intelligence sensors.
I mean it is a multi-dimensional area involving
almost all aspects of engineering if you want
to look at smell some aspects of chemical
engineering coming then there is no end it
is a very big area which grows in upon the
scientific expertise in almost every known
technology in the technology known to humans
so we will begin with industrial robots.
I show you here a simple industrial robot.
Built in our laboratory here it is known as
a SCARA robot it is a very simple device we
had built it this one of the earliest ones
we had built it has been built out of stepper
motors something which most of you are familiar
with and is controlled by a microprocessor
which into the right it could conduct and
replicate simple tasks repeatedly there were
three motions the main motion is the motion
of the base around vertical axis.
Second there is a sort of an elbow motion
and third there is an up-and-down motion of
the gripper as it moves up and down these
three motions we had put together using a
set of planes a set of drives stepper motor
drives and also arrack and pinion system for
the up and down motion we control these stepper
motors using the microprocessor and in between
the microprocessor and the robot you have
the drivers for the stepper motor and in such
through such a naughty fees we could control
the robot to do a variety of tasks here is
another robot.
We had in our laboratory this is driven by
servo models opposed to stepper motors so
obviously if you want to know in a stepper
motor you give the number of steps you know
how much the motor has rotated in a servo
motor the same thing is done by having what
is known as a feedback there are encoders
here which provide you the feedback and as
you notice the motors convey their motion
to the various joints through a set of chains
well as we go on we will see how this particular
device works.
I will now show you a short clip on this particular
device let me just show you how this device
can be used to transfer the contents of one
glass into another now it is a clip which
runs on for about one and a half minutes you
can see the robot you see the motions the
various motions the robot has got two fingers
you see the robot has approached the you have
got a glass there containing orange juice
the robot is speaking rapid picking it up
by the stem.
It is now lifting it up it is turning around
towards us you watch it will turn it is stretching
its arm goes to that position then turns and
then it is emptying this orange juice into
another cup very slowly it does not want to
spill and you see there it has completed emptying
the orange juice into another cup now it is
returning the stem glass to its original places.
So, we will now see apart from these robots.
We have got what are known as mobile robots
I show you here is a picture of one mobile
robot which is a tracked vehicle which can
explore uneven terrain as you can see you
can see a couple of motors driving through
chains the tracks here is another view you
can see the battery all the birds more or
less are required to carry their power on
board but they are not connected through wires
to a land source of power in the laboratory
or in the industry mobile robots invariably
have to carry their source of power on themselves
robots which are stationary like the Rhino
I had shown you they could be powered by from
a stationary power source but mobile robots
so whenever one designs these mobile robots
the ability to carry a lot of power in a compact
package becomes a limiting factor here is
another little robot.
Which can follow a line on the ground this
has been built by one of the companies established
by our students this robot can follow a line
which is drawn on the ground you have a white
line on the ground and this robot follows
it which always is you can draw shape figure
of eight and there are what would follow how
does it do it heroes it through a set of sensors
which allow me to sense the position of the
line and guides our abort accordingly here
is what is known as a walking device earlier
I had told you that walking robots can cross
over obstacles.
Can cross dead debris wherever there has been
an accident something which a wheeled robot
cannot do track vehicles can do but supposing
a track vehicle is asked to step over a pipe
which is at a height of maybe two feet from
the ground without damaging the pipe a track
vehicle will not be able to do it if you damage
the pipe whereas it walking device can step
over’s the pipe and walk off just like a
human being does without damaging a pipe.
I can cross a pipe here is one needle one
of the earliest walking machines built in
our laboratory here and it has one unknown
a single degree of freedom legs you can see
the leg is a mechanism what the leg essentially
does is this mechanism does means it permits
the leg to lift itself or throw itself forward
and come down so it was a single degree freedom
leg these are the limited capabilities.
There were six legs in the machine as you
could see here three leg on this side three
legs on the other side and it had a limited
capability because it has single degree of
freedom legs the legs were driven by stepper
motors so we could control when one legs moving
in there another.
Leg is stationary watch how you walk you notice
that when you lift and throw one of your legs
forward the other leg is stationary in the
case of these six legs robots here we have
three legs stationary at a time on the ground
to provide a tripod support and three other
legs are thrown forward thereby achieve stability
and as a robot where we have a leg with two
degrees of freedom a little bit of more freedom
than the previous leg you notice this leg
robot also has bought six legs again we are
aiming at static stability in order to keep
it stable there are six legs you can see the
black boxes there is these are the servo motors.
Which drive individual legs each leg has two
degrees of freedom so two servo motors are
they require to drive the leg now what do
I mean by two degrees of freedom look at yourself
you can move your shoulder and your elbow
can move this upland down and your elbow up
and down you need one motor here you need
one motor here similarly when you lift your
leg you need a hip joint and you also need
at the motor is the hip joint and they also
need a motor as the knee joint so this particular
robot has got something similar okay now we
will see this robotics shown carrying a camera.
On the front to go around and survey places
where there has been a little damage we use
this as a laboratory robot for our experiments
and it did work successfully it could see
and locate objects with the camera and move
towards.
Them here is a very sophisticated four legs
robot this is I bow built by son corporation
in its nose it has got an infrared sensor
which can detect the orange ball out there
then it has got a sound sensors which can
receive sound sand it can know determine from
which direction the sound is coming it has
many other sensors built into the system in
order to enable it to we have almost like
a real puppy this picture shows the AIBO playing
football.
The orange colored bar the curve ball is colored
orange in order to identify the ball to the
eyeball dog is a very popular one and it is
now being used as an entertainment pet by
senior citizens we now come to one more robot
which has been built here at it Bombay the
six select robot called Natraj this has six
legs unlike the previous robots which also
has six legs these six legs are disposed around
a circle as you notice here see.
There are six legs so we have them disposed
around a circle and you can notice that there
are red colored units on the robot these are
the actuators which actuate individual legs
each leg has three motors and a total of 18
legs are there as you can see there here the
red colored these are the motors each leg
has three motors so six legs makes it 18motors
in the central portion if the electronics
in the central well there is also a 486 computer
sitting in the central portion which synchronizes
the motion of all these 18 motors in order
to arrive at the particular way of walking
that's what we have done without natural reward
I will now show you a clip of the nitrogen
boot.
You will know watch the robot walking forward
and backwards as it walks forward and backwards
here we will see.
Here is the robot you can see the size of
the robot in comparison to the humans around
them you can have a look you can see the motors
the red and green ones as a motor then there
are ball screws which are used and then we
have all these now you can watch the walk
you can very clearly see the robot lifting
up three legs throwing them forward okay in
order to move the front two and the rear one
leg is moving is a very slow motion.
Because the robot is very heavy this was the
first walk it took.
I am showing you the video of the very first
walk the robot has taken it has taken about
two steps is taking a third you can see the
lights from the electronics the LEDs on the
central electronics in the central well which
are controlling all the motors all the18 motor
simultaneously notice that I am walking backwards.
So this robot can climb because it has three
degree of freedom legs it can lift the leg
up and climb any object now that you have
seen these all these types of robots let us
just summarize what we have seen?
When we extrapolate from nature we find that
there is an equivalence between humans and
animals and we are trying to imitate these
human and animal what if all that their abilities
that's what we are trying to visit the abilities
of the humans and animals for example we have
arms and fingers to manipulate objects robots
have similar capabilities we have legs for
locomotion robots have similar capabilities
and actuators are muscles in our case we have
electric actuators there have been hydraulic
actuators and pneumatic actuators.
In robot our eyes provide us vision and we
have cameras mounted on these robots I showed
you one little walking robot with the camera
which I all sit to see various objects around
it we have of course many more additional
sensors like the ability to sense smell scientists
are trying to develop equivalent for this
which could be used in robots we can hear
robots can hear using microphones converts
the sound into something useful we have a
tongue Forte we have a tongue in order to
taste food or whatever it is one day scientists
hope.
They could come out with robots for a similar
purpose and you know we have some very surprising
sensors like the skin which can sense temperature
which can send such a tactile sensing people
are attempting to come out with sensors of
similar nature for robots and we have nerves
for communicating with the brain there are
electronic devices for communicating with
the computer in a robot so when you look at
nature we are trying to mimic nature through
robotics and many a time in order to understand
robotics it suffices if you understand the
corresponding nature whenever I try to explain
to students how a NAM works .I am like the
one I had shown you transferring orange juice
from one class to another.
I usually use my hand as an example and tell
them that look if I were to command you to
rotate you are shoulder or your elbow by this
much 90degrees you would respond and the muscles
would as I actuators and they would fold the
elbow in a similar fashion in a robot also
we need this we need the muscles in the form
of portals we need something which could hear
our command convert it into your command to
the motors.
And move the motors through the necessary
angle so you can always use the analogy of
a human being or an animal in order to explain
many of the things that these robots could
do the we do the more easily we do not realize
how complex it is to convert our performance
into how to make a machine which would mimic
our performance is quite a complex task now.
Here I show you something which mimics fish
a submarine which was underwater this was
built by one of our students there is a small
propeller which is not shown here and it has
some electronics which allows it to send the
quality of water in a pipe or an air tank
both on the surface and below the surface
and transmit this data to a land station this
what happened here is a photo of a medical
robot.
Any surgeon if he wants to operate he cuts
open the body and then operates this is always
a dangerous thing because many bacteria aggression
and infection sets in now what they do is
they make a simple keyhole and through the
keyhole they send a little device in order
to cut a structure or suck blood or whatever
device is used for doing an operation the
devices are very tiny and they’re sent in
through a tube you can see three tubes being
sent into the body.
In this particular picture one tube carries
a camera so that the subject can visualize
what is going on and then he guides the little
robot which is passing through another tube
and guides it and commands it to do the task
which he thinks it ought to do okay, here
are examples.
So having seen the various types of robot
so let us look at some of the robotic components
here are the three motors which he had used
in our Natraj we had converted conventional
motors into servo motors you do get rid of
eight servo motors also in these motors you
have a feedback let us assume that the motor
rotates through about 20degrees how do you
know whether it has rotated through 20 degrees
obviously a potentiometer will allow you to
determine.
How much rotation has been you can always
measure the voltage output of the potentiometer
and determine such devices are incorporated
into servomotors and together with the assistance
of the two electronic boards which are shown
one can command the servo motor to rotate
through the given angles so on so here are
examples.
Of servo motors you will be seeing this as
you go along in the post here.
Is a leg of the robot you can see three motors
the Nataraj robot which we had built you can
see the three motors clearly they were reddish
looking once these three motors are the servo
motors.
I had mentioned in the earlier slides.
I had shown you in the earlier slide and these
three served to move the foot up down or to
the side left or to the right or to the front
or to the back this is what these three motors
are all so you see you have an upland down
motion which is provided by one of these three
motors a forward and backward motion provided
by a second motor and an ability to look to
the left or to the right provided by a third
motor okay now these three motors.
You know we had designed the special mechanism
as you can see there is a mechanism for the
leg this mechanism allowed us to decouple
these motions to a certain extent if not fully
and by commanding these three waters we could
get a variety of motions for the tip of the
foot of Natraj so here is an example of execution
of this all that we know in robotics into
something like this now the leg and the robot
or the other robot.
I had shown you earlier somewhat similar they
have the same what you call if you watch your
own leg and your hand you compare them the
shoulder is equal to the hip and the elbow
is equivalent to the knee so you know what
if you know how to design a robotic hand which
will transfer objects from place to place
you also know how to design leg for a walking
robot let me just show you a movie of the
walking robot the neckties the robot.
I will be showing you a movie of generalizing
about no he Nataj robot was built at it Bombay
as ahead set here you can see it is a massive
robot can see the various motors and I am
just repeating this in order to show you give
you an appreciation of the size of the robot
as well as you can see this so we have seen
these robots how they are whether they are
armed for robotic arm or a robotic leg they
are equivalent now let us see how is one going
to tell the robot what it is supposed to do
for the painting robot.
Once ready Channel he does it by what is known
as teaching by showing teaching by walkthrough
this is what we call it whenever you have
a child when you want the child to write the
alphabet what you tend to do is you have all
the child's hand and make them write the letter
A or B or whatever it is the child is holding
the chalk you hold the child's hand and lead
it through the places.
So this is called as lead through okay teaching
now this is typically used in painting as
you notice the birthday is handling the robot
he paints the card with this the motion of
the individual joints of the robot you have
seen that they are a robot group there are
motions as individual joints these are recorded
and when one’s replaced them you get the
robot performing the same tasks flawlessly
and repeatedly if the worker has painted it
badly there were obviously the result would
be a bad job of painting.
But very skilled workers are used for this
task they do an excellent job and then third
motion of the various joint is recorded and
replayed and whenever a car comes on the conveyor
there are what automatically replace a program
that it has been the replacing particular
you know program which has been stored and
painting is flawless so let us now go to the
next here is another way of teaching a robot
showing.
It what is the task to be done the entire
robot a listener on wilt is replicated as
a virtual world on a computer and the robot
is put through spaces in this virtual world
all the motion parameters all the parameters
associated with control of the robot are captured
taken down to the shop floor and the risk
is fed to the robot on the soft floor and
the robot on the soft floor faithfully reproduces
what has been programmed in the virtual world
the virtual world contains all the machines
sitting close to the robot all the loading
stations all the components so without much
of wastage of software time these robots are
programmed compare robots.
With the nature manipulation arms and fingers
raven by motors and as form a fluctuation
for vision we have cameras for hearing we
have microphones for smell they are yet to
develop for taste they are developing for
field what are known as tactile senses for
communication we have wires five fiber optics
and radio systems and for brains computers
and microprocessor.
This is what we have in robots as compared
to nature robots need not be so advanced you
know there are very simple devices which can
be used where you have hazardous tasks to
be conducted here.
I show you one such simple device.
This is device to climb up a pipe here you
have got one below in the center and two balloons
at each end now let us assume this is pushed
into a pipe and the balloon on the extreme
left is inflated it is in to pushed into a
vertical pipe with a balloon on the extreme
left interjects it is a vertical pipe and
the balloon inflates the whole thing hangs
said because the balloon top balloon is holding
on to the side of the walls then you push
it further and inflates the bottom balloon
the bottom balloon will hold on that deflects
the top balloon.
Once you do this you influence the intermediate
bellow so as to push the top balloon up though
it is deflated you can push it up very easily
once the top balloon has reached a particular
position.
okay you inflate it and grip the side of the
cube with it then deflect the bottom balloon
so that it does not touch the wall of the
tube and deflate the what if all the bellows
the bottom balloon Rises and goes up then
you repeat the cycle again by inflating the
bottom balloon deflating the top balloon deflating
the inflating the bellows you repeat the entire
cycle.
This how these simple devices can be used
you know we had done this device and used
it to climb the pipe it can go through curved
pipe salts so we have seen friends a lot about
various robots starting from very advanced
ones we also seen that it is possible to come
out very simple devices for robots now I shall
close this lecture before in the subsequent
lectures you will learn more details about
what are known as industrial robots and industrial
manipulators but before I do that I will show
you what is an example of autonomous capability
in this particular clip you will see an autonomous
robot solving a maze it is going through the
maze you can see that this has been built
by one of our it Bombay students wherever
there is a gap it senses the gap and moves
you can see how it has gone from the edge
of the maze to the center.
I will replay it again you will see the robot
.I know it senses a gap it moves you see the
speed at which it turns all this requires
a very careful attention to mechanical engineering
dynamics Saur on would have control and artificial
intelligence he uses artificial intelligence
to know where exactly the robot is going and
he captures the motions of the robot the turns
which has made memorizes them so that the
next time are only does not make the same
mistake it smacks the maze and solves them
a second time around.
At a very high-speed such a low robots could
be used to explore mines where you have no
reference points in order to know where you
are going you can move around randomly first
and find out and determine a map of the mind
use it to come back so such as the capabilities
here this particular example which I show
you is typically the capability of computer
science and artificial intelligence carried
to mechanical engineering the dynamics because
if you want to turn so fast you have to really
work out the dynamics properly otherwise.
It will keep spinning on the spot then electronics
you have to sense where the walls are if there
is ambient light changes the sensors will
not show you the exact location of the walls
because it will show you the ball and cross
the gap process and the fact that there is
a gap here all these factors so here is an
example of several disciplines coming together
into a successful product robotic product
and an autonomous award.
I think we will in the next class look at
industrial robots with this I conclude my
lecture and thank you for your attention.
