1. Robotics: Unit-I

2. Industrial Robotics Sections: Robot Anatomy Robot Control Systems
End Effectors
Industrial Robot Applications
Robot Programming

3. Industrial Robot Defined
A general-purpose, programmable machine possessing certain anthropomorphic characteristics
Hazardous work environments
Repetitive work cycle
Consistency and accuracy
Difficult handling task for humans
Multishift operations
Reprogrammable, flexible
Interfaced to other computer systems

4. Industrial Robot Applications
Material handling applications
Material transfer – pick-and-place, palletizing
Machine loading and/or unloading
Processing operations
Welding
Spray coating
Cutting and grinding
Assembly and inspection

5. Robot Anatomy Manipulator consists of joints and links
Joints provide relative motion
Links are rigid members between joints
Various joint types: linear and rotary
Each joint provides a “degree-of-freedom”
Most robots possess five or six degrees-of-freedom
Robot manipulator consists of two sections:
Body-and-arm – for positioning of objects in the robot's work volume
Wrist assembly – for orientation of objects
Base
Link0
Joint1
Link2
Link3
Joint3
End of Arm
Link1
Joint2

6. Manipulator Joints Translational motion Linear joint (type L)
Orthogonal joint (type O)
Rotary motion
Rotational joint (type R)
Twisting joint (type T)
Revolving joint (type V)

7. Joint Notation Scheme
Uses the joint symbols (L, O, R, T, V) to designate joint types used to construct robot manipulator
Separates body-and-arm assembly from wrist assembly using a colon (:)
Example: TLR : TR
Common body-and-arm configurations …

8. The Anthropomorphic System
The articulated system
Like a human arm (sections are joined together)
“Shoulder” and “Elbow” are used to refer to the two joints
More sections can be added if needed.
Most manoeuvrable
Used for paint spraying
Cannot cover a large area
Difficult to move the end of the arm in a straight line

9. Polar Coordinate Body-and-Arm Assembly
Notation TRL:
Consists of a sliding arm (L joint) actuated relative to the body, which can rotate about both a vertical axis (T joint) and horizontal axis (R joint)

10. The Polar System Spherical system Same Y and Z axes as cylindrical
Arm is pivoted so that it can rotate in the vertical plane instead of moving up and down along the z axis
This robotic arm can cover the surface of a sphere
Can move faster in the vertical direction than a cylindrical arm
Range of movement is much more restricted

11. Cylindrical Body-and-Arm Assembly
Notation TLO:
Consists of a vertical column, relative to which an arm assembly is moved up or down
The arm can be moved in or out relative to the column

12. The Cylindrical System
Similar to the cartesian except no X axis
Arm can rotate on a central support
Angle of rotation is referred to by the symbol ø
Three axis of motion (X, Y, and Z )
This robotic arm can move over the surface of an imaginary circle
Can move much faster than the cartesian robot arm
Can be used for loading or unloading

13. Cartesian Coordinate Body-and-Arm Assembly
Notation LOO:
Consists of three sliding joints, two of which are orthogonal
Other names include rectilinear robot and x-y-z robot

14. The Cartesian System The X, Y Z system – three independent directions
Best used when a large area needs to be covered
Not good when intricate movements are required
X axis allows the arm to move along the work piece
Y axis allows the arm to move towards and away from the work piece
Z axis allows movement upwards and downwards
The three movements are at 90 degrees to the other two
This robotic arm can move over the surface of an imaginary rectangle

15. Jointed-Arm Robot
Notation TRR:

16. SCARA Robot Notation VRO
SCARA stands for Selectively Compliant Assembly Robot Arm
Similar to jointed-arm robot except that vertical axes are used for shoulder and elbow joints to be compliant in horizontal direction for vertical insertion tasks

17. The SCARA System Selective Compliant Assembly Robot Arm
All revolute joints in the arm rotate about the vertical axes
Three degrees of freedom
Used for assembly operations

18. Wrist Configurations Wrist assembly is attached to end-of-arm
End effector is attached to wrist assembly
Function of wrist assembly is to orient end effector
Body-and-arm determines global position of end effector
Two or three degrees of freedom:
Roll
Pitch
Yaw
Notation :RRT

19. Example Sketch following manipulator configurations
(a) TRT:R, (b) TVR:TR, (c) RR:T.
Solution:

20. The Work Envelope
The work envelope is the area that a robot can cover.
The exact size and shape of the work envelope will be one of the main factors in deciding whether the robot is suitable for a particular job.
The size and shape vary enormously

21. Working Envelope