Definition and origin of robotics – different types of robotics – various generations of robots – degrees of freedom – Asimov's laws of robotics – dynamic stabilization of robots.
1. Robotics and Automation
EC 6003
[ELECTIVE]
Prepared By
JAI GANESH S
Asst.Professor – ECE
RMK College of Engineering and Technology
2. Unit 1 – Basic Concepts
• Definition and origin of robotics
• Different types of robotics
• Various generations of robots
• Degrees of freedom
• Asimov's laws of robotics
• Dynamic stabilization of robots
3. List of Reference
Unit # No.of
Period
Topic Text Book and
Reference Book
UNIT 1 - BASIC CONCEPTS
1 2 Definition and origin of robotics Mikell P Groover ( T1)
1 2 Different types of robotics Mikell P Groover ( T1)
1 1 Various generations of robots Deb S R ( R1)
1 1 Asimov's laws of robotics Mikell P Groover ( T1)
1 1 Degrees of freedom Mikell P Groover ( T1)
1 2 Dynamic stabilization of robots Online / Notes
4. Definition of a Robot:
• Word robot was coined by a Czech novelist
Karel Capek in a 1920 play titled Rossum’s
Universal Robots (RUR).
• Robota in Czech is a word for worker or
servant
5. • Official definition of robot was given by Robot
Industry Association (RIA), formerly known
as Robot Institute of America,
“A robot is a reprogrammable, multifunctional
manipulator designed to move material,
parts, tools or specialized devices through
variable programmed motions for the
performance of a variety of tasks”
6. Basic Parts of a Robot
Parts of the robot
– Manipulator
– Controller
– Teach pendant
7. AXES OF MANIPULATOR
6 axes
Servo motor control
Safety drives enable
Pay load of 16 kgs
10. Basic Parts of a Robot
• Manipulator / Rover : This is the main body
of the Robot and consists of links, joints and
structural elements of the Robot.
11. Basic Parts of a Robot
• End Effectors : This is the part that generally handles
objects, makes connection to other machines, or
performs the required tasks. It can vary in size and
complexity according to the applications / requirements.
12. Basic Parts of a Robot
• Actuators : Actuators are the muscles of the
manipulators. Common types of actuators are
servomotors, stepper motors, pneumatic cylinders
etc.
13. Basic Parts of a Robot
• Sensors : Sensors are used to collect information about the internal
state of the robot or to communicate with the outside environment.
Robots are often equipped with external sensory devices such as a
vision system, touch and tactile sensors etc which help to
communicate with the environment
14. Basic Parts of a Robot
• Controller : The controller receives data from the
computer, controls the motions of the actuator
and coordinates these motions with the sensory
15. Origin of a Robot
• The origin of industrial robots lies way back
in 1700's and have grown tremendously
over decades
16. Mid 1700 – J.de vaucanson
Built several human sized mechanical dolls that plays music
20. And many improvements
• 1959 – first commercial robot introduced by
planet corporation controlled by switches
• 1960 – first unimate robot introduced for
manipulator control
• 1966 – Trallfa, built and installed spray
painting robot
• 1968 – mobile robot named “shakey”
• 1971 – stanford arm, a small electrically
powered robot arm
21. Contd…
• 1973 – first computer type robot programming
language developed. (AL , WAVE)
• 1974 – invention of all electric drive robot
• Followed by industrial implementations for
manufacturing works
• 1979 – development of SCARA type robot
• 1982 – IBM introduced Robots for assembly using
robotic arm
• 1990’s – invention of walking robots and
rehabilitation robots, space robots, defense
applications
• 2000’s – Micro and Nano robots using smart
materials, underwater and ariel vehicles
22. Future robots
• Robotic engineers are designing the next
generation of robots to look, feel and act
more human, to make it easier for us to
warm up to a cold machine.
• Realistic looking hair and skin with
embedded sensors will allow robots to
react naturally in their environment.
27. Classification of robots
Based on Applications
• Industrial Robots
• Tele Robots
• Explorer Robots
• Laboratory Robots
• Hobbyist Robots
• Educational Robots
• Medical Robots
Based on Configuration
• Polar Configuration
• Cylindrical Configuration
• Cartesian Coordinate
Configuration
• Jointed Arm Configuration
Entire robots can be classified in to 2 broad categories:
28. Classification Based on Applications
• Industrial Robots:
– An industrial robot is a robot system used for
manufacturing. Industrial robots are automated,
programmable and capable of movement on three
or more axes.
29. Defining Parameters for industrial robots
• Number of axes– two axes
are required to reach any
point in a plane;
• three axes are required to
reach any point in space.
• To fully control the
orientation of the end of
the arm(i.e. the wrist)
three more axes (yaw,
pitch, and roll) are
required.
• Some designs (e.g. the
SCARA robot) trade
limitations in motion
possibilities for cost,
speed, and accuracy.
30. Defining Parameters for industrial robots
• Degrees of freedom– number of
independent motions that are allowed to the
body, this is usually the same as the number
of axes.
31. Defining Parameters for industrial robots
• Working envelope– an envelope is the
region of space a robot can reach during its
normal range of motion.
32. Defining Parameters for industrial robots
• Kinematics – the actual arrangement of rigid
members and joints in the robot, which determines
the robot's possible motions.
• Classes of robot kinematics include articulated,
cartesian, parallel and SCARA.
“Kinematics” the branch of mechanics concerned with the motion of objects
without reference to the forces which cause the motion.
37. Defining Parameters for industrial robots
• Carrying capacity or payload – how much weight a
robot can lift.
• Speed– how fast the robot can position the end of its
arm. This may be defined in terms of the angular or
linear speed of each axis or as a compound speed i.e.
the speed of the end of the arm when all axes are
moving.
• Acceleration – how quickly an axis can accelerate.
Since this is a limiting factor a robot may not be able
to reach its specified maximum speed for
movements over a short distance or a complex path
requiring frequent changes of direction.
38. Defining Parameters for industrial robots
• Accuracy – how closely a robot can reach a commanded
position. When the absolute position of the robot is measured
and compared to the commanded position the error is a
measure of accuracy. Accuracy can be improved with external
sensing, for example a vision system or Infra-Red. Accuracy can
vary with speed and position within the working envelope and
with payload.
• Repeatability – how well the robot will return to a programmed
position. This is not the same as accuracy. It may be that when
told to go to a certain X-Y-Z position that it gets only to within
1 mm of that position. This would be its accuracy which may be
improved by calibration. But if that position is taught into
controller memory and each time it is sent there it returns to
within 0.1mm of the taught position then the repeatability will
be within 0.1mm.
40. Classification Based on Applications
• Tele Robots
Tele robotics is the area of
robotics concerned with the
control of semi-autonomous
robots from a distance,
chiefly using Wireless
network (like Wi-Fi,
Bluetooth, the Deep Space
Network, and similar) or
tethered connections. It is a
combination of two major
subfields, teleoperation and
telepresence
41. Classification Based on Applications
• Explorer Robots
They are used to go where
humans cannot go and fear to
go. Eg: to explore cave, in deep
under water, to rescue people in
sunken ships. Used in Hazardous
Environments. Eg: Military
application
42. Classification Based on Applications
• Laboratory Robots
Laboratory robotics is
the act of using robots
in biology or chemistry
labs. For example,
pharmaceutical
companies employ
robots to move
biological or chemical
samples around to
synthesize novel
chemical entities or to
test
43. Classification Based on Applications
• Hobbyist Robots
This category of robots are
generally used for
entertainment purpose and
experimenting purpose. These
robots usually equipped with
speech synthesis techniques
44. Classification Based on Applications
• Educational Robots
Educational robotics is a broad term that
refers to a collection of activities,
instructional programs, physical platforms,
educational resources and pedagogical
philosophy. There are many schools which
are using the robot teacher.
45. Classification Based on Applications
• Medical Robots
A medical robot is a
robot used in the
medical sciences. They
include surgical robots.
These are in most tele
manipulators, which
use the surgeon's
actions on one side to
control the "effector"
on the other side.
46. Classification Based on Configuration
• Polar Configuration
Has one linear motion and
two rotary motions. It uses a
telescoping arm that can be raised or
lowered about a horizontal pivot.(α)
.The pivot is mounted on a rotating
base.(θ). A arm also has the capability to
move in and out to provide a linear
motion(x). The various joints provide the
robot with the capability to move its
arm within a spherical space and hence
it is also referred as Spherical coordinate
robot.
47. Classification Based on Configuration
These robots uses a vertical
column and a slide that can be
moved up or down along the
column. The robot arm is
attached to the slide so that it
can be moved radially with
respect to the column. By
rotating the column, the robot is
capable of achieving a work
space that approximates a
cylinder.
Work Envelope: Cylinder
Cylindrical Configuration
48. Classification Based on Configuration
Cartesian Coordinate Configuration
These robots uses three
perpendicular slides to
construct the x,y and z axes. Other
names are sometimes applied to
this configuration such as XYZ
robots and rectilinear robot. By
moving the three slides relative to
one another, the robot is capable
of operating within a rectangular
work envelope.
Work Envelope: Rectangular
49. Classification Based on Configuration
Jointed Arm Configuration
Jointed arm
configuration can be
classified in to 2 types:
(i) Jointed Arm Vertical
Configuration
(ii) Jointed Arm
Horizontal Configuration
(SCARA)
50. Work Volume or work Envelope
• The work volume is determined by the
following physical characteristics of the
robot:
– The robot's physical configuration (type of
joints, structure of links)
– The sizes of the body, arm, and wrist
components
– The limits of the robot's joint movements
53. Various Generations of Robots
• The evolution of robotics can be illustrated
as 4 generations
54. First generation @
Attended Robots
• A first-generation
robot is a simple
mechanical arm.
• These machines
have the ability to
make precise
motions at high
speed, many times,
for a long time
55. Second generation @
Robotics Process and Automation
• A second-generation robot has
rudimentary machine
intelligence.
• Such a robot is equipped with
sensors that tell it things about
the outside world.
• These devices include pressure
sensors, proximity sensors,
tactile sensors, radar, sonar,
ladar, and vision systems.
• A controller processes the data
from these sensors and adjusts
the operation of the robot
accordingly
56. Third generation @
Self Service and Automation
• The concept of a third-generation robot
encompasses two major avenues of evolving smart
robot technology
– The autonomous robot
• An autonomous robot can work on its own. It contains a
controller, and it can do things largely without supervision, either
by an outside computer or by a human being
– Insect robot
• There are some situations in which autonomous robots do not
perform efficiently. In these cases, a fleet of simple insect robots,
all under the control of one central computer, can be used.
• These machines work like ants in an anthill, or like bees in a hive.
58. Fourth generation @
Cognitive Robotics
• Any robot of a sort yet to be seriously put into operation is a
fourth generation robot.
• Examples of these might be robots that reproduce and evolve, or
that incorporate biological as well as mechanical components.
59. Fifth Generation @
Artificial Intelligence Robotics
• Robot controller will involve complete artificial
intelligence (AI), miniature sensors, and
decision making capabilities.
61. Asimov's laws of robotics
• The Three Laws of Robotics or Asimov's
Laws are a set of rules devised by the science
fiction author Isaac Asimov
First Law - A robot may not injure a human being or,
through inaction, allow a human being to come to
harm.
Second Law - A robot must obey the orders given it
by human beings except where such orders would
conflict with the First Law.
Third Law - A robot must protect its own existence
as long as such protection does not conflict with the
First or Second Laws.
62. First Law - A robot may not injure a human being or, through inaction, allow a
human being to come to harm
• A tool must not be unsafe to use. Hammers
have handles and screwdrivers have hilts to
help increase grip.
• It is of course possible for a person to injure
himself with one of these tools, but that injury
would only be due to his incompetence, not the
design of the tool
63. SecondLaw - A robot must obey the orders given it by human beings except where
such orders would conflict with the First Law
• A tool must perform its function efficiently
unless this would harm the user.
• This is the entire reason ground-fault circuit
interrupters exist.
• Any running tool will have its power cut if a
circuit senses that some current is not
returning to the neutral wire, and hence
might be flowing through the user.
• The safety of the user is paramount
64. Third Law - A robot must protect its own existence as long as such protection does not
conflict with the First or Second Laws
• A tool must remain intact during
its use unless its destruction is
required for its use or for safety.
• For example, Dremel disks are
designed to be as tough as
possible without breaking unless
the job requires it to be spent.
• Furthermore, they are designed to
break at a point before the
shrapnel velocity could seriously
injure someone (other than the
eyes, though safety glasses should
be worn at all times anyway).
66. Degrees of freedom
• Industrial robots are designed to perform productive
work such as pick and place, welding, assembly, etc.,
the work is accomplished by enabling the robot to
move its body, arm and wrist through a series of
motion and positions. The individual joint motions
associated with the performance of a task are referred
to by the term Degrees of Freedom (DOF)
"Degrees of freedom, in a mechanics context, are
specific, defined modes in which a mechanical
device or system can move. The number of
degrees of freedom is equal to the total number
of independent displacements or aspects of
motion."
67. Joints and its types
• The robot's motion are accomplished by
means of powered joints.
• Three joints are associated with the action
of body and arm.
• Another three joints are generally used to
actuate the wrist
• Joints used in the industrial robotics are of
two types,
– Prismatic Joints - Used for Linear Motions
– Revolute Joints - Used for Rotational Motions
68. prismatic joint
• A prismatic joint provides a linear sliding
movement between two bodies, and is often
called a slider, as in the slider-crank linkage.
A prismatic pair is also called as sliding pair.
A prismatic joint can be formed with a
polygonal cross-section to resist rotation.
69. revolute joint
• A revolute joint (also called pin joint or hinge joint)
is a one-degree-of-freedom kinematic pair used in
mechanisms.
• Revolute joints provide single-axis rotation function
used in many places such as door hinges, folding
mechanisms, and other uni-axial rotation devices
70. types of rotating joints
• (i) Rotational joint (R Joint)
• (ii) Twisting joint (T Joint)
• (iii) Revolving joint. (V Joint)
71. Degrees of Freedom Associated with Arm and Body of the
Robot
• Vertical Traverse: This is
the capability to move the
wrist up or down to provide
the desired vertical attitude.
• Radial Traverse: This is the
capability to move the wrist
front and back which
provides the extension and
retraction movement.
• Rotational Traverse: This is
the capability to rotate the
arm in vertical axis.
72. Degrees of Freedom associated with wrist of robot
• Wrist Roll: Also called as wrist
swivel, this involves rotation of
the wrist mechanism about the
arm axis
• Wrist Pitch: Given that the
wrist roll is in the centre
position, the pitch would
involve the up and down
rotation of the wrist. this is also
sometimes called as wrist bend
• Wrist Yaw: Given that the wrist
roll is the centre position , the
Yaw would involve the right or
left rotation of the wrist.