This document provides an overview of robotics and robots. It begins with definitions of a robot and discusses the history and development of robotics. It then covers the three laws of robotics proposed by Isaac Asimov. The document describes the main components of a robotic system including the robotic arm, end effector, sensors, and control computer. It discusses different robot configurations, specifications, applications, and the needs and disadvantages of robots.

1. ME8099 ROBOTICS
Presented by,
Mr. Abilash S
Assistant Professor
Department of Mechanical Engineering

4. UNIT I FUNDAMENTALS OF ROBOT
Robot – Definition
• A machine that looks and acts like a human being.
• An efficient but insensitive person
• An automatic apparatus.
– Something guided by automatic controls.
E.g. remote control
• A computer whose main function is to produce
motion.
An industrial robot is a programmable,
multi-functional manipulator designed to move
materials, parts, tools, or special devices through
variable programmed motions for the performance
of a variety of tasks”

5. Robotics History
 The term “robot” was derived from Czech word
“robota”.
 “robota” means labourer or worker.
 Karel Capek used the term in his play “Rossum's
Universal Robots”.
 Isaac Asimov coined the term “Robotics” and
postulated the three laws of robotics.

6. Three Laws of Robotics
 A robot may not injure a human being or through
inaction, allow a human being to come to harm.
 A robot must obey the orders given to it by
human beings except where such orders would
conflict with the First Law.
 A robot must protect its own existence as long as
such protection does not conflict with the First or
Second Law.

7. Robot System
 A robotic arm with actuators
 End effector
 Sensors
 Control computer system
 Communication peripherals
 Power supply

8. Robotic Arm

9. Wrist Motion
 Yaw – Rotary motion executed about 𝑧 axis.
Causes movement in left and right directions.
 Pitch – Rotary motion executed about 𝑦 axis.
Causes movement in up and down directions.
 Roll – Rotary motion executed about 𝑥 axis.

10. Robot Specification – Physical
Mechanical
• Robot configuration
• Number of axes of movement
•Floor space required for
mounting
• Weight
• Physical dimensions
• Physical details
Power
• Power drive system
• Power/services requirements
Control
 Programming method
 Type of control system
 External sensors
supported
 Program backing
storage device
 Memory size

11. Co-ordinate Systems or Robot
configurations
 Rectangular (or) Cartesian
configuration
 Cylindrical (or) Post-type
configuration
 Spherical (or) Polar configuration
 SCARA (Selective Compliance Assembly Robot Arm)
or Joint-arm configuration

12. Work Envelope
Robot Work Envelope or Reach
Robot reach, also known as the work envelope or
work volume, is the space of all points in the
surrounding space that can be reached by the robot
arm. Reach is one of the most important characteristics
to be considered in selecting a suitable robot because
the application space should not fall out of the selected
robot's reach.

13. Work Envelope
 For a Cartesian configuration the reach is a rectangular-
type space.
 For a cylindrical configuration the reach is a hollow
cylindrical space.
 For a polar configuration the reach is part of a hollow
spherical shape.
 Robot reach for a jointed-arm configuration does not have
a specific shape
 The work envelop is described by the surface of the work
space.

14. Rectangular (or) Cartesian configuration
Robots with Cartesian configurations consist of
links connected by linear joints (L). Gantry robots are
Cartesian robots (LLL).

15. Cylindrical (or) Post-type configuration
Robots with cylindrical configuration have one
rotary (R) joint at the base and linear (L) joints
succeeded to connect the links

16. Spherical (or) Polar configuration
Robots with cylindrical configuration have two
rotary (R) joints at the base and link with one linear (L)
joint succeeded to connect the link.

17. Pendulum Robot System

18. SCARA (Selective Compliance Assembly Robot
Arm) or Joint-arm configuration
The jointed-arm is a combination of cylindrical and
articulated configurations. The arm of the robot is
connected to the base with a twisting joint. The links in
the arm are connected by rotary joints. Many
commercially available robots have this configuration

19. Robot configurations
Configuration Advantages Disadvantages
Cartesian
coordinates
3 linear axes, easy to visualize,
rigid structure, easy to program
Can only reach front of itself,
requires large floor space, axes
hard to seal
Cylindrical
coordinates
2 linear axes +1 rotating, can
reach all around itself, reach
and height axes rigid,
rotational axis easy to seal
Can’t reach above itself, base
rotation axis as less rigid, linear
axes is hard to seal, won’t reach
around obstacles
SCARA
coordinates
1 linear + 2 rotating axes,
height axis is rigid, large work
area for floor space
2 ways to reach point, difficult to
program off-line, highly
complex arm
Spherical
coordinates
1 linear + 2 rotating axes, long
horizontal reach
Can’t reach around obstacles,
short vertical reach
Revolute
coordinates
3 rotating axes can reach above
or below obstacles, largest work
area for least floor space
Difficult to program off-line, 2
or 4 ways to reach a point, most
complex manipulator

20. Robot Motion and Trajectories
Robot Motion
 Point to point motion – The path has no importance.
 Continuous path motion – The path taken is very important.
Trajectories
 Path taken by the robot end effector within the work
volume is known as trajectory.
 Trajectory planning.
 Joint interpolated trajectory planning.
 Cartesian path trajectory planning.

21. Robot Classification
 Classification based on intelligence level
 Classification based on servo control system
 Classification based on drive systems
 Classification based on geometric configuration of the arm
 Miscellaneous types

22. Classification Based on Intelligence
Level
 Sequence control robots – Fixed sequence and Variable
sequence control robots
 Playback robots – Point to point and continuous path robots
 Numerically controlled robots
 Servo control robots – Hydraulic and electric robots. Uses
closed loop control system
 Non servo control robots – Pneumatic robots. Uses open
loop control system
Classification Based on Servo Control
System

23. Classification Based on Drive Systems
 Pneumatic robots – light load, cheaper, no accurate
positioning, light weight mechanism.
 Hydraulic robots – heavy load, expensive, firm and rigid
positioning, bulky mechanism.
 Electric robots – medium load, accurate positioning, easily
controlled by electronic controllers, light weight
mechanism.

24. Classification Based on Geometric
Configuration of the Arm
 Cartesian coordinate robots
 Polar coordinate robots
 Cylindrical robots
 Articulated or Jointed arm robots
 Pendulum robots
 Spine robots
 Multiple arm robots

25. Robot Specifications
 Accuracy, resolution, repeatability, speed and payload.
 Number of degrees of freedom.
 Geometric configuration of the manipulator.
 Maximum and Minimum reach.
 Type of Drive system.
 Type of Control system.

26. Robot Specifications
 Programming method.
 Memory capacity.
 Supported communication protocols and interface ports.
 Input power supply requirements.
 Total robot weight and installing procedures.

27. Degrees of Freedom
 Degrees of freedom (DOF) is defined as the ability of a
joint to produce linear or rotary movement when
actuated.
 Number of DOF for a robot is equal to the number of
joint axes in the robotic arm.

28. The Robotic Joints
A robot joint is a mechanism that permits relative
movement between parts of a robot arm. The joints of a
robot are designed to enable the robot to move its end-
effector along a path from one position to another as
desired.

29. Robotic Joints Notation

30. Robot Parts and Functions
 Controller: Every robot is connected to a computer, which
keeps the pieces of the arm working together. This
computer is known as the controller. The controller
functions as the "brain" of the robot.
 Arm: Robot arms come in all shapes and sizes. The arm is
the part of the robot that positions the endaffector and
sensors to do their pre-programmed business.
 Drive: The drive is the "engine" that drives the links (the
sections between the joints into their desired position.
Without a drive, a robot would just sit there, which is not
often helpful

31. Robot Parts and Functions
 End-Effector: The end-effector is the "hand" connected to
the robot's arm. It is often different from a human hand -
it could be a tool such as a gripper, a vacuum pump,
tweezers, scalpel, blowtorch - just about anything that
helps it do its job.
 Sensor: Most robots of today are nearly deaf and blind.
Sensors can provide some limited feedback to the robot
so it can do its job. The sensor sends information, in the
form of electronic signals back to the controller

32. Robot Parts and Functions
 End-Effector: The end-effector is the "hand" connected to
the robot's arm. It is often different from a human hand -
it could be a tool such as a gripper, a vacuum pump,
tweezers, scalpel, blowtorch - just about anything that
helps it do its job.
 Sensor: Most robots of today are nearly deaf and blind.
Sensors can provide some limited feedback to the robot
so it can do its job. The sensor sends information, in the
form of electronic signals back to the controller

33. Need for Robots
 Consistent production quality.
 High production quantity.
 Can be employed at hazardous places.
 Improvement in productivity, minimal Material wastage,
reduced work in Progress and faster through put times.
 Highly flexible to accommodate product Design changes.

34. Need for Robots
 Working conditions are improved.
 Occupational safety for workers is achieved.
 Higher load carrying capacity.
 Available at all times.
 Manufactures can stay ahead in the market with state of
the art robotic production facilities.

35. Applications of Robot
With different payload capability, reach and design,
articulate robots are designed to employ in the following
applications:
 Arc welding
 Spot welding
 Assembly
 cleaning/spraying
 Cutting
 Deburring
 Die casting
 Gluing/sealing

36. Applications of Robot
• Grinding/Polishing
• Injection moulding
• Machine tending
• Material handling
• Packing
• Palletizing
• Picking
• Pre-machining
• Press brake tending

37. Disadvantages of Robots
 High initial investment.
 Inventory of endeffectors should be maintained.
 Expensive spares and accessories.
 Needs skilled personnel for programming.
 Increases the risk of human unemployment.

38. THANK YOU