2. Components of Industrial Robot
• Mechanical unit: It refers to the robot’s manipulative arm and its base.
• It Consists of fabricated structural frame with provisions for supporting
mechanical linkage and joints, guides, actuators and sensors.
• Drive: Drive system supplies the power which enables the robot to move.
• Drive for a robot may be hydraulic, pneumatic or electric.
3. • Control System: Controller is the brain of the robot.
• It is a communication and information processing
device that initiates, terminates and coordinates the
motions and sequences of a robot.
• Industrial robots incorporate microprocessor based
controllers that performs interface with sensors,
grippers ,tooling and peripheral devices.
• Tooling: it is manipulated by the robot to perform the
functions required for the application.
• According to functional capabilities, it may be
integrated with robot’s mechanical system or may be
attached at robot’s wrist end effector interface.
5. Robot Wrist and end of Arm Tools
• Six axis coordinates are required by a robot to
specify the location and orientation of an
object.
• Three Co-ordinates are x,y and z.
• Other three coordinates are achieved by
adding wrist and hand movements with the
end of arm tooling.
6. Three Basic types of wrist motions
• Pitch: Rotational or bending movement in a vertical
plane.
• Yaw: Rotational or twisting movement in a horizontal
plane.
• Roll: Rotational or swivel movement.
8. End Effector
• It is a device at the end of the robot arm.
• Two main types of end effectors:
A) Grippers
• Grippers are devices which can be used for holding or
gripping an object.
• These includes mechanical hands and may be hooks,
magnets and suction devices which can be used for
holding or gripping.
B) Tools
• Tools are devices which robots use to perform
operations on an object.
• E.g drills, grinders, paint sprays other tool which get a
specific job done.
10. Robot Terminology
1. Links and Joints: Links are solid structural
members of a robot.
• Joints are the moveable couplings between
them.
11. Robot with six degree of Freedom
2. Degree of Freedom(dof):
• It is the number of independent movements a robot can
realize with resect to its base.
• The number of axes is normally the same as the number of
degrees of freedom of robot.
• Each joint on the robot introduces a degree of freedom.
13. 3)Orientation Axis: If tool is held at fixed position, the
orientation determines which direction it can be
pointed.
• Pitch, yaw and roll are common orientation axes.
4) Position Axis: The tool can be moves to number of
positions in space.
14. 5)Tool Center Point(TCP): TCP is used when
referring to the robots positions as well as focal
point of the tool.
• TCP can be specified in Cartesian, Cylindrical
and spherical co-ordinates depending on the
robot.
15. 6) Accuracy: It describes how close the arm will be
when it moves to desired point.
7) Precision(validity): It is defined as how accurately a
specified point can e reached.
8) Repeatability(Variability): It is how accurately the
same position can be reached if the motion is repeated
many times.
16. 9)Work envelope/Workspace: A robot can only work in area in
which it can move.
It determines how far the robot’s arm can reach and how flexible
the robot is.
10) Stability: It refers to robot motion with the least amount of
oscillations.
11) Speed: It refers to the maximum velocity that is achieved by
TCP or by individual joints.
It vary over the workspace as the geometry of robot changes.
17. 12) Payload: It is the weight a robot can carry
and remain within its specifications.
13) Reach: It is the maximum distance a robot
can reach within its workspace.
14) Settling Time: It is the time required for the
robot to be within given distance from the final
positions.
18. Robotic Joints
• It is a mechanism that permits relative movement
between parts of a robot arm.
• Basic movements required for desired motion of a
robot:
a) Rotational movement: This enables the robot to
place its arm in any direction on horizontal plane.
b) Radial movement: This enables the robot to move its
end effectors radially to reach distant points.
c) Vertical Movement: This enables the robot to take its
end effectors to different heights.
19. Joints depending on the nature of relative
motion
1. Prismatic Joints(Sliding/linear): It permits links to make
linear displacement along a fixed axis.
• These joints are used in gantry, cylindrical or similar joint
configuration
2. Revolute Joints: It is used where a pair of links rotates about a
fixed axis.
20. Variations of Revolute joints
• Rotational Joint(R): This is identified by its motion,
rotation about an axis perpendicular to the adjoining
links.
21. Revolute Joints
• Twisting Joint(T): Rotation takes place about an axis that is
parallel to both adjoining links.
• Revolving Joint(V): Rotation takes place about an axis that is
parallel to one of the adjoining links.
• Links are aligned perpendicular to one another at this kind of
joint.
