Kinematics and Dynamics of Robotics

1. Chapter 1
Introduction to Robotics
Dr. Pramod Sreedharan
Dept of Mechanical Engineering
Amrita Vishwa Vidyapeetham, Amritapuri Campus

2. Karel Capek (January 9, 1890 – December 25, 1938)
He wrote the play R.U.R. (Rossum’s Universal Robots) staged on 2nd January 1921
and introduced the word Robot meaning forced labor.
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3. Isaac Asimov (January 2, 1920 – April 6, 1992)
“Three laws of robotics” (introduced in his 1942 short story “Runaround”)
1. A robot may not injure a human being or, through inaction, allow a human
being to come to harm.
2. A robot must obey the orders given to it by human beings except where such
orders would conflict with the First Law.
3. A robot must protect its own existence as long as such protection does not
conflict with the First or Second Laws.
4. Near the end of his book Foundation and Earth, a zeroth law was introduced:
0. A robot may not injure humanity, or, by inaction, allow humanity to come
to harm.
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4. Deliverables:
To become a Robotics engineer to build robots, which are
economical, to solve problems in society.
Requirements:
Interest
Imagination and
Creativity
Applied Science
or Technology
Physical Systems
Mathematics
Physics
of
System
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5. Robot Types:
1. Manipulators, eg. Painting, Welding, Material
Handling, Pick and Place, etc.,
2. Mobile Robots, Wheeled and Legged types,
3. Hybrid Robots, eg. Humanoid Robots,
4. Prosthesis,
5. Intelligent Environments,
6. Multi-body System or Swarm Robots.
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6. Intelligence Requirements:
1. Perception using Sensors such as Computer
Vision and Digital Image Processing,
2. Communication using Natural Language
Processing,
3. Knowledge Representation developed from First
Order Logic, Boolean Algebra and Learning
such as Supervised, Unsupervised, Reinforced
Learning,
4. Automated Reasoning.
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7. Software Requirements:
1. C++, C#, Java,
2. Python (interpreter language) using various
libraries and packages including:
Jupyter and Spyder for interactive
programming,
Pandas, NumPy, SciPy, Matplotlib, etc., which
are data analysis packages,
3. Robot Operating System (ROS), along with
Gazebo and RViz, etc.,
4. Solidworks, Ansys, Adams, Matlab, Simulink,
Simechanics, etc.
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8. Hardware Requirements:
Robot is a computer controlled intelligent electro-
mechanical machine using suitable electronic
circuitry between computer and electrical
actuators, sensors, SLAM systems.
1. Computer,
2. Electronic circuitry,
3. Electrical, Pneumatic or Hydraulic Actuators,
4. Mechanical System,
5. Sensors,
6. Instrumentation, Control System, GPS, etc.
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9. Mathematical Requirements:
1. Calculus and Differential Equations,
2. Vector and Linear Algebra,
3. Vector and Matrix Calculus,
4. Boolean Algebra and First-Order Logic,
5. Optimization theory,
6. Statistics and Probability.
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10. Definition
A robot is a software-controllable
mechanical device that uses sensors to
guide one or more end-effectors through
programmed motions in a workspace in
order to manipulate physical objects.
Industrial Robots are also called as
Robotic Arms or Robotic Manipulators.
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11. Robotic Manipulator
modelled as a chain of links
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12. Serial Robotic Manipulator and it’s
ideological parent - the human arm
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13. Serial Robotic Manipulator
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14. Serial Robotic Manipulators
▪ They are the most common type of
Industrial Manipulators.
▪ They are a $ 2 Billion industry.
▪ They are an open kinematic chain of
mechanical links.
▪ They are physically anchored at the
base.
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15. Components of a Robotic
Manipulator
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16. Base and Tool Coordinate
Frames for a Manipulator
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17. Schematic Diagram of a
Robotic Manipulator
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18. Few types of Manipulators
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19. Master Manipulator
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20. Surgery Robot (Slave
Manipulator)
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21. Master-Slave Control
Scheme
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22. Hard and Soft Robots
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23. Control Scheme of a Robotic
Manipulator
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24. Relative cost-effectiveness
of Soft Automation
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25. Types of Robot Joints
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26. Classification of Robots
1. Drive Technologies such as Electric,
Pneumatic and Hydraulic. Electric drives
are generally DC Servomotors or DC
Stepper motors.
2. Work-Envelope Geometries.
3. Motion Control Methods:
i. Point-to-point control and,
ii. Continuous path control.
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27. Work Envelope Geometries
based on Major Axes
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28. Work-Envelope Geometries (contd.)
a. Cartesian,
x-y-z or P-P-P,
b. Gantry,
x-y-z or P-P-P,
c. Cylindrical,
θ-z-r or R-P-P,
d. Spherical,
θ-Φ-r or R-R-P,
e. SCARA,
θ-Φ-z or R-R-P,
f. Articulated,
θ-Φ-Ψ or R-R-R.
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29. 29

30. Cartesian Robotic Manipulator
(P-P-P)
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31. Gantry Robotic Manipulator
(P-P-P)
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32. Cylindrical Robotic
Manipulator (R-P-P)
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33. Spherical Robotic Manipulator
(R-R-P)
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34. SCARA (Selective Compliance
Assembly Robot Arm) Robotic
Manipulator (R-R-P)
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35. Articulated Robotic
Manipulator (R-R-R)
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36. Articulated Robotic Manipulator
(Z-Y-Z Spherical Wrist)
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37. Parallel Robotic
Manipulators
a. Closed Chain with
Parallelogram.
b. Parallel.
eg. Stewart’s Platform.
c. Hybrid parallel-serial.
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38. Delta Robot (Parallel Robot)
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39. Gough-Stewart Platform
(Hexapod Platform) Parallel
Robot
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40. Gough-Stewart Platform
(6 DoF Platform) Parallel Robot
AMiBA Radio Telescope
Application: Flight Simulator
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41. Comparison between Parallel
and Serial Manipulators
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42. Configuration of Spherical Wrist
Designs
a. pitch-yaw-roll (YXZ) b. roll-pitch-roll (ZYZ)
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43. Robotic Arm with a Spherical
Wrist
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44. Main operating area and secondary
operating area for a robotic arm with a
spherical wrist
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45. Robot Motion Control
Applications
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46. 46

47. Robot Applications (valued at $
12.3 billion globally), 2019
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48. Applications of Industrial
Robots
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49. Robot Specifications or
Characteristics
1.Number of axes,
2.Load carrying capacity, kg,
3.Maximum speed, mm/s,
4.Reach and Stroke, mm,
5.Tool orientation, deg,
6.Repeatability, mm,
7.Precision and Accuracy, mm,
8.Operating environment.
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50. Rhino XR-3 Robot
Specifications (contd.)
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51. Rhino XR-3 Robot
Specifications (contd.)
Load Shaft Precision
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52. Function of Robot Axes
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53. Reach and Stroke of a
Cylindrical robot
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54. Tool Orientation
(Yaw-Pitch-Roll or X-Y-Z system)
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55. Repeatability, Precision and
Accuracy
Repeatability is a measure of the ability of a robot
to position the tool tip in the same position
repeatedly.
Precision of a robot is the spatial resolution with
which the tool can be positioned within the work
envelope.
Accuracy of a robot is a measure of the ability of
the robot to place the tool tip at an arbitrarily
prescribed position in The work envelope.
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56. Repeatability, Precision and
Accuracy (contd.)
Note: Error depends on:
1. gear backlash,
2. elastic deformations in links due
to loading.
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57. Repeatability, Precision and
Accuracy (contd.)
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58. Horizontal Precision of a
Cylindrical Robot
where, ∆h = overall horizontal precision,
∆p = total robot precision,
∆Φ = load shaft precision.
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59. Slotted Disk with 2-bit Gray
Code
where, ∆Φ = overall incremental
load shaft precision,
m = gear reduction ratio,
k = number of slots around
the circumference of
the disk,
d = number of emitter-detector
pairs.
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60. Operating Environment
1.Harsh, dangerous and unhealthy
environments such as transport of
radioactive materials, spray painting,
welding, loading and unloading of
furnaces, etc.
2. Clean rooms are required for
semiconductor industry, where
temperature, humidity and airflow are
controlled.
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61. Thank You
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