Robotics course information

1. Robotics and Control (ME452 )
Dr. Himanshu Pathak
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2. Course Syllabus
Course Content:
• Introduction to Robotics: Basic definitions, mechanism, degree of freedom, classification
and specifications of Robots, Industrial Robots, sensors, controller, actuator.
• Robot Kinematics: Position and orientation of links, Coordinate transformation, d-h
parameters, joint variable and position of end effectors, forward and inverse kinematic
analysis. Velocity analysis – Jacobian and Singularity. Static force analysis.
• Trajectory Planning: Joint Space Trajectory Planning, Cubic Polynomial Path Generation,
Obstacle Avoidance.
• Robot Dynamics: Derivation of dynamics equation based on Newton Eulers formulation and
Lagrangian formulation.
• Robot Control: Actuators - hydraulic, pneumatic, electric motors, Sensors – position,
velocity, proximity, force and pressure, Position control- Proportional-Integral-Derivative
control, servo compensation. Force control – Impedance control, hybrid control (force +
position control), introduction to nonlinear control of manipulators.
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3. Course Reference & Evaluation
Textbook:
• Craig John J., “Introduction to robotics: Mechanics & Control”, 3rd Ed., Pearson. 2008.
• Tsuneo Yoshikawa, “Foundations of Robotics – Analysis and Control”, 1990.
• Subir Kumar Saha, “Introduction to robotics”, Mc Graw Hill.
• Mittal R.K., Nagrath I.J., “Robotics and Control”, Mc Graw Hill.
Assignments/Tutorial 10 %
Quiz-I 25 %
Quiz-II 25 %
End-term Exam 40 %
Total 100 %
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Assessment Scheme ???
Lecture: Mon, Tues & Thurs
Consult Time: Tues 2:00 – 3:00 at G1-110. himanshu@iitmandi.ac.in

4. Course Objective
Students who successfully complete the course will demonstrate the following outcomes by
lectures, tutorials, quiz and tests:
• To introduce the basic concepts, parts of robots and types of robots.
• To make the student familiar with the various drive systems for robot, sensors and their
applications in robots and programming of robots.
• An understanding of the basic concepts associated with the design and functioning
and applications of Robots.
• An understanding of the robotics kinematics, inverse kinematics and designing of robot
components for expected objectives.
• A knowledge of Trajectory Planning for robot moving members.
• A knowledge of various kind of control systems for robotics application.
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5. Lecture-1 Questions
• Make a chart showing the major events in the development of industrial robots over the
past 30 years in chronically manner.
• Give all possible application of robots.
• List all components of robotic system.
• Define Degree of Freedom.
• In a sentence of two, define: Kinematics, Workspace and Trajectory.

6. Robot: A multi-functional operator which can be controlled by programs. It moves the
materials, components, tools and other special apparatus through control programs to
finish a series of work. (American Robots Association)
Karel Capek (1920): A Czech novelist coined term Robot in his
novel titled Rassum’s Universal Robots (RUR). Robot in Czech
is a word for worker or servant.
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Leonardo da Vinci (1500): Created many human-inspired,
robot-like sketches, designs, and models in the 1500’s.
Historical Aspects
Isaac Asimov (1930): A visionary who envisioned a positronic
brain for controlling robots; much earlier than the invention of
computer.
Joseph Engleberger and George Devoe (1961): Fathers of
industrial robots; built the first industrial robot (PUMA),
inspired by the human arm.

7. Robotics Timeline

8. Real vs Fiction
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9. Automation
Hard Automation: Can’t handle product design
variation.
Programmable: Flexible because of computer
control.
Autonomous: Endowed with decision making
capability through use of sensors and feedback
system.
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Automation: The complete process to achieve desirable product/service
without human intervention.

10. Utility of Robot
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Hazardous
Environment
Painting
Handling
Toxic/Explosive/Nuc
lear/Biological
Material
Welding
Repetitive
Task
Assembly
Operations
Loading and
Unloading
Machine Tools
Handlin Fragile
and Tiny parts
Exploration
Space Rovers
Strategic
Operations &
Surveillance
Deep Sea Search

11. Law of Robotics
1st Law: A robot should not injure a human being
or, through inaction, allow a human to be
harmed.
2nd Law: A robot must obey orders given by
humans except when that conflicts with the first
law.
3rd Law: A robot must protect its own existence
unless that conflicts with the first or second law.
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Issac Asimov: Introduce humanoids and postulated rules for their ethical conduct.

12. Components
Arms and Fingers: to Manipulate objects.
Leg: for locomotion.
Muscles: Actuators.
Eye, Nose, Tounge, Skin: Sensors.
Nerves: for Communication.
Brain: Controller
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Extrapolating Robotics Parts from Nature
Actuators: Motors, Pneumatic and Hydraulic,
Polymer, Shape Memory alloy.
Sensor: Camera, Microphone, Tactile Sensor.
Communication: Wire, Fibre Optics, Radio.
Controller: Computers and Micro-processor
Energy Source: AC Supply, Generator, Battery.

13. Components
1. Mechanisms (Mechanical Structure)
2. End Effecters
3. Tools
4. Sensors
5. Actuators
6. Controllers
7. Energy Source
8. Locomotion (Wheel/Leg)
9. Programming Interface
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Parts of Industrial Robot System

14. 1. Dynamic system Modeling and analysis
2. Feedback control
3. Sensors and signal conditioning
4. Actuators (muscles) and power electronics
5. Hardware/computer interfacing
6. Computer programming
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Typical knowledgebase for the design and operation of robotics systems
Knowledgebase for Robotics

15. Mechanism
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Links: Links are rigid parts.
Joints: Joints permit relative motion between links.

16. Kinematic Pair/Joints in Robotics
According to nature of relative motion:
• Prismatic/Sliding Pair: Links have a sliding motion relative to each other.
• Revolute/Turning Pair: Pairs has a turning/revolving motion between them.
• Rolling Pair: Pair are connected in such a way that one rolls over another fixed link.
• Screw pair: One element can turn about the other by screw threads.
• Spherical pair: Elements of a pair are connected in such a way that one element
(with spherical shape) turns or swivels about the other fixed element.
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17. Degree of Freedom
A rigid body free in space has six degree of freedom:
3 for translation (position) and 3 for rotation (orientation).
3 Translations: Representing linear motions along three mutually perpendicular axes.
3 Rotations : Represent angular motions bout the three axes.
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DOF: Number of independent movements that an object can perform in a 3D space.
• 3 translation motion along x, y and z axis.
• 3 rotational motion in yz, xy and xz plane.
The connection of link with another impose
certain constraints on their relative motion.
DOF = 6 – Number of restrains,

18. Mobility of Mechanism
Number Synthesis:
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N= total number of links in mechanism; P1 = Number of pairs having one DOF;
P2= Number of pairs having two DOF; F = Total DOF for mechanism.
In mechanism, one link if fixed.
Number of movable link = (N-1); DOF of (N-1) movable links = 6(N-1)
The pairs having 1 DOF, will impose 5 restrains can reduce DOF by 5P1; pairs having 2 DOF
will impose 4 restrain on each corresponding link will reduce DOF by 4P2.
Similarly, 3, 4 and 5 DOF links will reduce corresponding DOFs of the mechanism.
Therefore, F = 6(N-1) - 5P1 - 4P2 - 3P3 - 2P4 – P5 (3-D Mechanism)
For 2-D mechanism: F = 3(N-1) - 2P1 - 1P2 (Gruebler’s Criterion)
F = 3(N-1) - 2P1 (Kutzback’s Criterion)

19. Arm Configuration
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Arm is used to provide reachable workspace to wrist.
Mechanism of arm depends on type of three joints employed and their
arrangement.
Links are long enough to provide for maximum reach in the space.
Arm must be mechanically robust to provide sufficient strength and stiffness to
bear load of work piece, wrist and endeffector.
According to joint movements and arrangement of links:
Cartesian Configuration- all three P joints.
Cylindrical Configuration- one R and two P joints.
Polar (spherical) Configuration – two R and one P joints
Articulated (Revolute or Jointed Arm) Configuration- all three R joints.

20. Arm Configuration
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Cantilevered Cartesian Gantry/Box Cartesian
PPP Joints

21. Arm Configuration
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Cylindrical Configuration
PRP Joints RRP Joints
Spherical Configuration

22. Arm Configuration
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Articulated Configuration/
Arthropomorphic Manipulator
Combined Cylindrical and Articulated
SCARA Configuration
RRR Joints

23. Wrist Configuration
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Wrist: Part of Manipulator, enable manipulator to orient the end-effecter to perform
the task properly.
Hold only rotary joints, 3-DOF wrist may provide rotation about three mutually
perpendicular direction.
Must be Compact.
Wrist assembly attached to end of arm.
End effecter is attached to wrist assembly.
3-DOF of Wrist.
Roll.
Pitch
Yaw

24. End-Effecter
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End-Effecter: External part of Manipulator, attached to wrist and use to interact with
environment to get done desirable work.
It’s DOF do not combine with the manipulator’s DOF.
1. Gripper: Use to grasp or hold the work piece during the work cycle.
2. Tools: A assembly mounted with wrist to apply some work on the contact of
other material.

25. Gripper
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Mechanical grippers
Vacuum gripper
Magnetic gripper
Gripper with Adhesive Strips

26. Tools
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Spray Paint Guns
Welding guns
Tool head for Drilling and Milling
Welding/Heating Torch
Screw Driver

27. Human Arm vs Robotic Arm
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The design of Human Arm mechanism is unique Marvel and is still a challenge to
replicate with the same DOF and flexible movement.
1. -180o ≤ Roll ≤ +90o
2. -90o ≤ Pitch ≤ +50o
3. -45o ≤ Yaw ≤ +15o
A. 2-DOF Upper Arm
B. 1 DOF Forearm
C. Upperarm length/forearm length=1.2
D. 4-DOF Fingers

28. Sensor
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Reads actual variables in robot motion for use in control.
Human senses: sight, sound, touch, taste, and smell provide us vital information to
function and survive.
Robot sensors: measure robot configuration/condition and its environment and send
such information to robot controller as electronic signals (e.g., arm position, presence
of toxic gas)
Robots often need information that is beyond 5 human senses (e.g., ability to: see in
the dark, detect tiny amounts of invisible radiation, measure movement that is too
small or fast for the human eye to see)

29. Actuators
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Provides force/torque for robot motion.
Common robotic actuators utilize combinations of different electro-mechanical
devices.
 Synchronous motor
 Stepper motor
 AC servo motor
 Brushless DC servo motor
 Brushed DC servo motor

30. References
• Craig John J., “Introduction to robotics: Mechanics & Control”, 3rd Ed., Pearson. 2008.
• Tsuneo Yoshikawa, “Foundations of Robotics – Analysis and Control”, 1990.
• Subir Kumar Saha, “Introduction to robotics”, Mc Graw Hill.
• Mittal R.K., Nagrath I.J., “Robotics and Control”, Mc Graw Hill.