INDUSTRIAL ROBOTICS Module- II.pdf

1
Complied By- Kamesh Mechrocks
INDUSTRIAL ROBOTICS
Course code-MEP504
Module-II
Grippers and Manipulators-Gripper joints, Gripper force, Serial manipulator, Parallel
Manipulator, selection of Robot-Selection based on the Application (8hrs)
Grippers:
 A gripper is a robotic end-effector or tool designed to grasp and hold objects. Grippers are
crucial components of robotic systems, allowing robots to interact with their environment
and perform various tasks.
 Grippers come in different types, each with specific features to accommodate various
object shapes, sizes, and materials.
 Gripper joints are the movable components that enable the gripper to adapt to different
shapes and sizes.
Let's explore some common types of grippers and their joints:
Common Types of Grippers:
 Finger Joints:
Finger Joints in Grippers:
Description:
Finger joints in grippers emulate the structure and movement of human fingers. This design allows
robotic systems to mimic the dexterity and adaptability of the human hand.
Design:
 Structure: Grippers with finger joints typically consist of two or more fingers. These fingers can
move independently or in coordination.
 Independence: The ability of the fingers to move independently provides a high degree of
adaptability, enabling the gripper to conform to the shape of irregularly shaped objects.
 Articulation: The joints between the fingers allow for articulation, making it possible for the
gripper to grasp objects from various angles and orientations.

2
Applications:
Finger joint grippers find application in scenarios where flexibility in grasping various object
shapes is crucial. Some specific use cases include:
 Irregularly Shaped Objects: Finger joints excel at grasping objects with non-uniform or irregular
shapes, adapting to the contours of the items.
 Variable Size Objects: The flexibility of finger joints allows the gripper to adjust its grip to
accommodate objects of different sizes.
 Dynamic Environments: In environments where the objects to be manipulated are diverse and
unpredictable, finger joint grippers offer versatility.
Examples:
 Pick and Place Tasks: Finger joint grippers are often employed in pick and place tasks where the
gripper needs to handle a variety of items with different shapes and sizes.
 Assembly Lines: In assembly processes that involve components with varying geometries, finger
joint grippers provide the adaptability required for efficient handling.
In summary, finger joint grippers play a crucial role in applications that demand the ability to grasp
and manipulate objects with diverse shapes and sizes, showcasing the importance of mimicking the
human hand's flexibility in certain robotic tasks.
Parallel Jaws in Grippers:
Description:
Parallel jaws in grippers feature two parallel surfaces that move together. This design is particularly
well-suited for grasping flat or regularly shaped objects with a consistent geometry.
Design:
 Parallel Surfaces: The key characteristic of parallel jaws is the presence of two surfaces that
maintain a parallel orientation throughout the gripping process.

3
 Simultaneous Movement: The jaws move in parallel, meaning they close or open together. This
design simplifies the gripping process and enhances the efficiency of object manipulation.
 Precision: The parallel motion ensures a uniform grip on the object, making it suitable for
applications where precise positioning and alignment are essential.
Applications:
Parallel jaw grippers find applications in scenarios where precision and simplicity in object
manipulation are critical. Some specific use cases include:
 Flat Objects: Well-suited for grasping flat materials, such as sheets, boards, or panels.
 Regularly Shaped Items: Effective in handling objects with consistent geometries, where
maintaining parallel contact is crucial.
 Pick and Place Tasks: Commonly used in pick and place applications, especially when the objects
have uniform shapes and dimensions.
Examples:
 Packaging Lines: Parallel jaw grippers are employed in packaging systems to handle boxes,
cartons, or other regularly shaped packaging materials.
 Material Sorting: In manufacturing processes where materials with standardized shapes need to be
sorted, parallel jaw grippers provide a straightforward and efficient solution.
In summary, parallel jaw grippers are designed to excel in applications that demand precision and
simplicity, particularly when dealing with regularly shaped or flat objects. Their parallel motion
simplifies the gripping process and enhances the overall efficiency of the robotic system.
Suction Cups in Grippers:
Description:
Suction cup grippers utilize vacuum pressure to hold objects securely. This design is particularly
effective for objects with smooth or flat surfaces.

4
Design:
 Suction Cup Mechanism: The gripper incorporates a suction cup, a flexible and airtight material
that conforms to the object's surface.
 Vacuum System: Connected to the suction cup is a vacuum system. This system creates a pressure
differential between the inside of the cup and the external environment, resulting in a vacuum seal
when attached to the object.
 Attachment and Release: The suction cup attaches to the object by removing the air within the
cup, creating a vacuum. To release the object, air is allowed back into the cup, breaking the vacuum
seal.
Applications:
Suction cup grippers are well-suited for applications where holding objects with smooth or flat
surfaces is necessary. Specific use cases include:
 Glass Handling: Ideal for lifting and moving glass sheets or products with glass surfaces.
 Tile Handling: Effective in picking up and placing tiles during manufacturing or assembly
processes.
 Smooth Object Manipulation: Suitable for handling objects like metal sheets, plastic sheets, or
any item with a smooth and flat surface.
Examples:
 Automated Assembly Lines: Suction cup grippers are commonly used in assembly processes,
especially when dealing with objects that require careful handling and precise placement.
 Material Transfer in Warehouses: In logistics and warehouses, suction cup grippers are employed
for moving items like smooth-surfaced boxes or packages.
In summary, suction cup grippers provide a reliable and efficient solution for handling objects with
smooth or flat surfaces. Their vacuum-based mechanism ensures a secure grip, making them
valuable in applications where precision and gentle handling are crucial.

5
Rotary Joints in Grippers:
Description:
Grippers with rotary joints are designed to enable the gripper to rotate an object. This rotational
capability is particularly valuable when manipulating objects with specific orientations, and it
allows for enhanced flexibility in the grasping and handling process.
Design:
 Rotational Freedom: The key feature of a gripper with rotary joints is the ability to rotate around a
specific axis. This provides additional degrees of freedom to the gripper, enhancing its adaptability
to various object orientations.
 Axis of Rotation: The joint allows the gripper to rotate around a predefined axis, which can be a
vertical or horizontal axis, depending on the design and application requirements.
 Controlled Rotation: The gripper can be designed to rotate the object with precision, ensuring
accurate positioning during manipulation.
Applications:
Rotary joint grippers find valuable applications in scenarios where the orientation of the grasped
object is critical to the task. Some specific use cases include:
 Assembly Processes: Useful for assembling components that require a specific orientation.
 Packaging Tasks: Beneficial in packaging applications where the proper alignment of items is
essential.
 Material Handling: Valuable in situations where the orientation of the material being transported
needs to be controlled.
Examples:
 Automotive Assembly: Grippers with rotary joints can be utilized in assembling automotive parts
that have specific alignment requirements.
 Electronics Manufacturing: In the manufacturing of electronic devices, rotary joint grippers can
assist in positioning components accurately.
In summary, grippers with rotary joints provide an additional level of flexibility and control in
robotic manipulation, particularly when precise orientation of the grasped object is critical to the
success of the task at hand. Their ability to rotate objects contributes to the versatility of robotic
systems in various industrial applications.
 Rotational Joints:
Rotational joints in grippers are mechanical components that allow the gripper to rotate
around a specific axis. These joints provide a pivotal or twisting motion, enabling the gripper to
change the orientation of the grasped object. Grippers with rotary joints offer an additional degree
of freedom, enhancing the versatility of robotic systems in manipulating objects with specific
alignment requirements.

6
Applications:
1. Assembly Processes:
o Description: In assembly tasks where components need precise positioning or alignment,
grippers with rotary joints facilitate controlled rotation during the assembly process.
o Application: Used in manufacturing lines for assembling products that require specific
orientations of individual parts.
2. Packaging Tasks:
o Description: Grippers with rotary joints play a crucial role in packaging applications, where
items need to be oriented correctly before being packaged.
o Application: Employed to manipulate items on conveyor belts or assembly lines to ensure
they are in the desired orientation for packaging.
3. Material Handling:
o Description: In material handling scenarios, rotary joints are valuable for manipulating
objects with specific orientations, such as rotating sheets of material for further processing.
o Application: Applied in industries where the orientation of materials (e.g., metal sheets,
glass panels) is critical for subsequent manufacturing steps.
Examples:
1. Automotive Assembly:
o Description: Grippers with rotary joints are used in automotive assembly lines to position
and assemble components that require specific orientations.
o Example: Placing and aligning a part like a wheel or a gear in an automobile assembly
process.
2. Electronics Manufacturing:
o Description: Grippers with rotary capabilities are essential in electronics manufacturing for
handling and positioning components on circuit boards.
o Example: Orienting electronic components like microchips or connectors for precise
placement on a circuit board.
3. Food Industry:
o Description: In the food processing and packaging industry, grippers with rotary joints are
employed to handle and position food items before packaging.
o Example: Ensuring that food products like cookies or candies are properly aligned on a
conveyor belt before being packaged.
In summary, rotary joints in grippers enable controlled rotation, making them valuable in
applications where precise object orientation is crucial. Whether in assembly, packaging, or
material handling, these gripper joints contribute to the efficiency and accuracy of robotic systems.
Linear Joints in Grippers:
Description:
Linear joints in grippers facilitate controlled linear motion, allowing the gripper to move in a
straight line. These joints are crucial for adjusting the grip width, enabling the gripper to adapt to
objects of varying sizes and shapes. Linear motion is often essential for precise and controlled
manipulation during the grasping process.

7
Applications:
1. Precision Gripping:
o Description: Linear joints are used in grippers for tasks that require precise and controlled
gripping, especially when dealing with objects that demand careful handling.
o Application: Applied in industries where accuracy in grasping is critical, such as electronics
assembly or delicate materials handling.
2. Variable Object Sizes:
o Description: Grippers with linear joints are effective in handling objects of different sizes,
as the linear motion allows for the adjustment of the grip width.
o Application: Commonly used in scenarios where the gripper needs to handle a range of
object sizes on the same production line.
3. Pick and Place Operations:
o Description: Linear joints are valuable in pick and place applications where the gripper
must precisely position objects at specific locations.
o Application: Used in manufacturing and logistics for accurately placing items on conveyor
belts or packaging lines.
Examples:
1. Electronics Assembly:
o Description: Linear joints in grippers are utilized in the assembly of electronic components,
where precise and controlled manipulation is essential.
o Example: Handling delicate electronic parts and placing them on a circuit board with
accuracy.
2. Warehousing and Logistics:
o Description: Grippers with linear joints find applications in warehouses for picking and
placing items of various sizes onto shelves or conveyor systems.
o Example: Efficiently handling packages of different dimensions in a logistics center.
3. Pharmaceutical Industry:
o Description: Linear joints are employed in grippers for pharmaceutical manufacturing,
ensuring the precise and careful handling of medication packaging.
o Example: Picking up and placing pharmaceutical products on a production line with
accuracy.
In summary, linear joints in grippers play a crucial role in enabling controlled linear motion. This
feature is particularly valuable in applications that demand precision, adaptability to variable object
sizes, and accurate positioning during pick and place operations.
Pneumatic or Hydraulic Actuation in Grippers:
Description:
Pneumatic or hydraulic actuation refers to the method by which grippers are powered and
controlled. In this system, either compressed air (pneumatic) or hydraulic fluid (hydraulic) is used
to generate the force needed to open and close the gripper, allowing it to grasp and release objects.
Both systems leverage the principles of fluid dynamics to transmit power and achieve controlled
motion.

8
Pneumatic Actuation:
 Working Principle: Pneumatic grippers use compressed air as the working fluid to create
motion. The controlled release of compressed air generates force, enabling the gripper to
move and apply pressure.
 Advantages:
o Quick Response: Pneumatic systems offer rapid response times, making them suitable for
high-speed applications.
o Simple Design: Pneumatic grippers are often simpler in design, which can result in cost-
effective solutions.
 Applications:
o Pneumatic grippers are commonly used in manufacturing and industrial automation for
tasks requiring rapid and straightforward gripping, such as pick and place operations on
assembly lines.
Hydraulic Actuation:
 Working Principle: Hydraulic grippers use hydraulic fluid (usually oil) as the working
medium. The controlled flow of hydraulic fluid through a system of valves and cylinders
generates the force necessary for gripping and releasing.
 Advantages:
o High Force: Hydraulic systems can provide substantial gripping force, making them suitable
for handling heavy loads.
o Precise Control: Hydraulic grippers offer precise control over force and speed, making them
suitable for applications requiring accuracy.
 Applications:
o Hydraulic grippers are often employed in heavy-duty industrial applications, such as lifting
and manipulating large and heavy objects in manufacturing or construction.
Considerations:
1. Speed vs. Force: Pneumatic systems are generally faster, while hydraulic systems excel in
providing high force. The choice depends on the specific requirements of the application.
2. Environmental Factors: Hydraulic systems may be preferred in environments with
extreme conditions, as hydraulic fluids can handle a wider range of temperatures and resist
contaminants better than compressed air.

9
3. Complexity and Cost: Pneumatic systems are often simpler and more cost-effective for
lighter applications, while hydraulic systems may be more complex but offer higher force
capabilities.
In summary, the choice between pneumatic and hydraulic actuation in grippers depends on factors
such as the required force, speed, precision, and environmental conditions of the application. Each
system has its advantages, and the selection is based on the specific needs and constraints of the
task at hand.
Electric Actuation in Grippers:
Description:
Electric actuation in grippers involves the use of electric motors or solenoids to generate the force
needed for gripping and releasing objects. Unlike pneumatic or hydraulic systems, electrically
actuated grippers rely on the conversion of electrical energy into mechanical motion to control the
opening and closing of the gripper.
Working Principle:
 Electric Motors or Solenoids: Electric grippers typically feature motors or solenoids as the
primary actuation components. The motor-driven mechanism or solenoid action generates
the force required to operate the gripper.
 Controlled by Electrical Signals: The motion and force of the gripper are controlled by
electrical signals, allowing for precise and programmable operation. This enables the
adjustment of grip force and speed according to specific application requirements.
Advantages:
1. Precision and Control:
o Electric grippers offer precise control over grip force and speed, making them suitable for
applications requiring fine manipulation and accuracy.
2. Adjustability:
o The parameters of electric grippers can often be easily adjusted, allowing for flexibility in
handling various objects and accommodating changes in the production process.

10
3. Clean and Quiet Operation:
o Electric actuators produce less noise compared to pneumatic systems. They also do not
require compressed air or hydraulic fluid, contributing to a cleaner and quieter working
environment.
4. Energy Efficiency:
o Electric grippers can be more energy-efficient than pneumatic or hydraulic systems,
especially in applications where precise control is needed, and the gripper is not in constant
operation.
Applications:
1. Electronics Assembly:
o Electric grippers are commonly used in the assembly of electronic components, where
precise and controlled manipulation is essential.
2. Laboratory Automation:
o Electric grippers find applications in laboratory settings where precision and
programmability are critical for handling delicate samples or equipment.
3. Small Part Handling:
o Electric grippers are suitable for tasks that involve handling small parts or components
where fine motor control is required.
Considerations:
1. Force and Load Capacity:
o Electric grippers come in various sizes and force capacities. The selection should match the
specific requirements of the application, considering the weight and type of objects to be
manipulated.
2. Response Time:
o While electric grippers can offer precise control, the response time may be slower compared
to pneumatic systems. The application's speed requirements should be considered.
3. Cost:
o Electric grippers can have a higher upfront cost, but this may be offset by reduced operating
costs over time, especially in energy-efficient and low-maintenance applications.
In summary, electrically actuated grippers provide a versatile and precise solution for applications
that demand controlled and programmable gripping. The choice between electric, pneumatic, or
hydraulic actuation depends on specific application requirements and considerations.
Gripper Force:
Gripper force refers to the strength or pressure exerted by a robotic gripper during the grasping or
holding of an object. It is a critical parameter in robotic systems as it determines the gripper's
ability to securely hold objects of varying sizes, weights, and shapes. The force applied by the
gripper must be carefully controlled to prevent damage to delicate objects while ensuring a secure
grip on heavier or more rigid items.
Key Points:
1. Adaptability:

11
o Gripper force needs to be adaptable to different objects and applications. A gripper should
be capable of adjusting its force based on the characteristics of the object being
manipulated.
2. Precision:
o Precision in gripper force is essential for tasks that require accurate positioning or delicate
handling. The ability to finely control the force allows the gripper to manipulate objects
without causing damage.
3. Variable Gripping Scenarios:
o Gripper force requirements can vary based on the application. For example, delicate tasks
such as handling glass or electronic components may require a gentle grip, while tasks like
material handling may demand a stronger force.
4. Safety:
o Controlling gripper force is crucial for ensuring the safety of both the robotic system and its
surroundings. Excessive force can lead to damage or injury, and insufficient force may
result in dropped or mishandled objects.
Factors Influencing Gripper Force:
1. Object Properties:
o The weight, size, shape, and surface characteristics of the object being gripped influence the
required force. Irregularly shaped or slippery objects may require different gripping
strategies.
2. Application Requirements:
o The specific task or application determines the optimal gripper force. For example,
assembly tasks may require a different force than pick-and-place operations or material
handling.
3. Gripper Design:
o The design of the gripper, including the type of joints, fingers, or end-effectors, can impact
the force it can exert. Different gripper designs are suitable for different force applications.
4. Sensors and Feedback:
o Advanced robotic systems often incorporate force sensors and feedback mechanisms to
continuously monitor and adjust the gripper force in real-time. This ensures adaptability to
changing conditions.
Examples:
1. Assembly Line:
o In an assembly line, grippers need to apply enough force to securely hold and position
components during the assembly process without damaging them.
o Grippers used in material handling applications must exert sufficient force to lift and
transport heavy objects, ensuring a secure grip throughout the process.
3. Electronics Manufacturing:
o Grippers in electronics manufacturing must be capable of exerting precise and controlled
force to handle delicate electronic components without causing damage.
In conclusion, gripper force is a critical parameter in robotic systems, impacting their ability to
perform tasks accurately, safely, and efficiently. The proper control and adjustment of gripper force
contribute to the overall effectiveness of robotic applications across various industries.

12
Serial Manipulator:
A serial manipulator is a type of robotic arm composed of a series of connected segments or links.
These links are joined by joints, and each joint allows rotational or translational motion, providing
the robot with multiple degrees of freedom (DOF). The end-effector, located at the tip of the
manipulator, is responsible for interacting with the environment, grasping objects, or performing
specific tasks.
Key Features:
1. Linked Segments:
o A serial manipulator consists of a sequence of linked segments, often referred to as links or
arms. These links are connected by joints, allowing relative motion between them.
2. Joints:
o Joints are the articulation points connecting adjacent links. Different types of joints provide
various degrees of freedom, enabling the robot to move in specific ways.
3. Degrees of Freedom (DOF):
o The total degrees of freedom of a serial manipulator are the sum of the individual DOFs of
its joints. Each joint contributes to the robot's ability to move in a particular direction or
orientation.
4. End-Effector:
o The end-effector is the tool or device located at the end of the manipulator. It is responsible
for interacting with the environment, performing tasks, or manipulating objects.
5. Control System:
o Serial manipulators are controlled through a system that manages the movement of each
joint. The control system interprets commands and coordinates the motion of the
manipulator to achieve the desired tasks.
Applications:
1. Industrial Manufacturing:

13
o Serial manipulators are widely used in manufacturing for tasks such as assembly, welding,
painting, and material handling. Their versatility allows them to adapt to various production
line requirements.
o Serial manipulators excel in material handling applications, where they can pick up,
transport, and place objects with precision and efficiency.
3. Pick and Place Operations:
o Serial manipulators are well-suited for pick and place tasks, commonly found in industries
such as logistics, warehousing, and packaging.
4. Assembly Lines:
o In automated assembly lines, serial manipulators play a crucial role in assembling
components, aligning parts, and performing intricate tasks with high precision.
5. Surgery and Medical Applications:
o In the field of medicine, serial manipulators are utilized in robotic surgery, allowing for
precise and minimally invasive procedures.
Advantages:
1. Versatility:
o Serial manipulators are versatile and can be adapted for various applications, making them
suitable for a wide range of industries.
2. Precision:
o With precise control over each joint, serial manipulators can perform tasks with high
accuracy, making them valuable in applications requiring precision.
3. Scalability:
o Serial manipulators can be designed with different sizes and configurations to meet specific
requirements, making them scalable for different tasks and workspaces.
In summary, serial manipulators are integral components of industrial automation, known for their
flexibility, precision, and applicability to diverse tasks across different industries.
Parallel Manipulator:
A parallel manipulator is a type of robotic system that features multiple arms (kinematic chains)
connected to a common platform, and the end-effector is manipulated by the coordinated motion of
these arms. Unlike serial manipulators, where the links are connected in series, in a parallel
manipulator, the links act in parallel to control the position and orientation of the end-effector.

14
Key Features:
1. Multiple Kinematic Chains:
o Parallel manipulators consist of several kinematic chains, each with its own set of joints and
links. These chains operate concurrently to manipulate the end-effector.
2. Common Platform:
o The arms are connected to a common platform, providing a rigid and stable structure. This
platform is often referred to as the mobile platform or the end-effector platform.
3. Actuation:
o Actuators are responsible for driving the motion of each kinematic chain. The coordinated
movement of these actuators allows precise control over the position and orientation of the
end-effector.
4. High Precision:
o Parallel manipulators are known for their high precision and stiffness. The parallel structure
enhances rigidity, making them suitable for applications that demand accurate and
controlled movements.
5. Reduced Inertia:
o The parallel configuration typically results in lower inertia compared to serial manipulators,
enabling faster acceleration and deceleration during motion.
Applications:
1. Precision Machining:
o Parallel manipulators are utilized in precision machining tasks, such as milling, drilling, or
engraving, where high accuracy and stability are crucial.
2. Flight Simulators:
o In the aerospace industry, parallel manipulators are employed in flight simulators to provide
realistic and precise motion control.
3. Medical Robotics:
o Parallel manipulators find applications in medical robotics for surgical procedures requiring
accuracy and stability, such as image-guided surgery.
4. 3D Printing:

15
o The high precision and stability of parallel manipulators make them suitable for 3D printing
applications, ensuring accurate layer-by-layer deposition of materials.
5. Optics and Camera Systems:
o Parallel manipulators are used in applications involving optics, cameras, or sensors where
precise positioning and stability are essential.
Advantages:
1. High Rigidity:
o The parallel structure contributes to high rigidity, making parallel manipulators suitable for
tasks that require resistance to external forces and vibrations.
2. Accuracy and Precision:
o Parallel manipulators offer superior accuracy and precision in positioning the end-effector,
making them ideal for applications demanding high levels of control.
3. Stable Platform:
o The common platform provides stability, allowing for controlled and precise movements
without the risk of deflection or deformation.
4. Reduced Inertia:
o The reduced inertia enables faster and more dynamic movements, making parallel
manipulators suitable for applications requiring rapid and precise motion.
In summary, parallel manipulators are valued for their exceptional precision, stability, and rigidity.
They are particularly well-suited for applications demanding high levels of accuracy and control,
such as precision machining, medical robotics, and aerospace simulations.
Selection of robots:
 The selection of robots indeed involves careful consideration of various factors to ensure
optimal performance in specific applications. Here's a concise recap:
Application-Based Selection:
o Choose robots equipped with grippers suitable for efficient picking, placing, and
transporting of materials.
2. Assembly Line:
o Opt for robots with precise manipulators to ensure speedy and accurate assembly of
components on the production line.
3. Welding:
o Select robots with specialized end-effectors designed for welding applications, considering
factors such as precision and heat resistance.
4. Painting/Coating:
o Choose robots with appropriate tools for uniform and controlled painting or coating
processes, ensuring even application.
5. Medical:
o For delicate medical tasks, select robots with specialized end-effectors designed for surgery,
diagnostics, or other medical applications.

16
Other Considerations:
1. Payload Capacity:
o Ensure the robot has the necessary payload capacity to handle the weight of the objects it
will manipulate during its tasks.
2. Reach and Workspace:
o Select a robot with the required reach and workspace, considering the spatial requirements
of the specific application.
3. Speed and Accuracy:
o Consider the desired speed and precision for the tasks at hand, choosing a robot that aligns
with these performance requirements.
4. Environmental Conditions:
o Evaluate the environmental conditions of the application (e.g., temperature, humidity) and
choose a robot that can operate effectively in those conditions.
In conclusion, a thorough understanding of the application's requirements, combined with
considerations such as payload capacity, reach, speed, and environmental suitability, is crucial for
the successful selection of robots. This ensures that the chosen robotic system is well-suited to
perform the intended tasks efficiently and effectively.
Multiple choice questions:
Module-II:
1. Grippers and Manipulators - Gripper Force:
Question: What is the primary function of gripper force in a robotic system?
a. To determine the robot's speed
b. To calculate the power consumption
c. To assess the gripping capability
d. To regulate the robot's temperature
Answer: c. To assess the gripping capability
Reference: Gripper force is crucial for evaluating a gripper's ability to securely hold and
manipulate objects during robotic tasks.
2. Grippers and Manipulators - Serial Manipulator:
Question: In a serial manipulator, how are the robot's links connected?
a. In parallel
b. In series
c. In a mesh network
d. In a circular configuration

17
Answer: b. In series
Reference: In a serial manipulator, the links are connected in a series, with one link following the
other.
3. Grippers and Manipulators - Parallel Manipulator:
Question: What is a characteristic feature of parallel manipulators?
a. High payload capacity
b. Low mechanical stiffness
c. Limited workspace
d. Independent movement of multiple limbs
Answer: d. Independent movement of multiple limbs
Reference: Parallel manipulators have multiple limbs connected to the end-effector, allowing for
independent movement.
4. Selection of Robot - Selection based on the Application:
Question: When selecting a robot for a pick-and-place application requiring high speed and
precision, which type of robot is generally preferred?
a. SCARA Robot
b. Cartesian Robot
c. Delta Robot
d. Articulated Robot
Answer: c. Delta Robot
Reference: Delta robots are often preferred for high-speed pick-and-place applications due to their
rapid and precise movements.
Important Questions:
Gripper Joints (Remember - Level 1):
Q. List and name three types of gripper joints commonly used in robotic systems. Provide a brief
description of each.
Ans: Gripper joints play a crucial role in robotic systems, enabling the manipulation and control of
objects. Here are three commonly used types of gripper joints along with brief descriptions:

18
1. Rotational (or Revolute) Joint:
o Description: The rotational joint allows rotation around a specific axis. It provides a
single degree of freedom, enabling the gripper to rotate or pivot. This type of joint is
often employed in robotic arms and grippers for tasks that require simple rotational
movement, such as pick-and-place operations or assembly tasks.
2. Linear (or Prismatic) Joint:
o Description: The linear joint facilitates linear or translational motion along a
specific axis. It allows the gripper to move in a straight line, providing a single
degree of freedom for linear positioning. Linear joints are commonly used in
applications where precise linear movements are essential, such as in CNC
machining or material handling.
3. Universal Joint:
o Description: The universal joint, also known as a Cardan joint, allows rotational
movement in two perpendicular axes. It provides more flexibility than a single
rotational joint and is often used when the gripper needs to adapt to objects at
different angles. Universal joints are suitable for tasks that require a wider range of
motion, such as manipulating objects with varying orientations.
These gripper joints are chosen based on the specific requirements of the robotic application,
considering factors like the desired motion, the type of objects to be manipulated, and the level of
precision needed for the task. The selection of the appropriate gripper joint is crucial for the overall
efficiency and effectiveness of the robotic system.
Gripper Force (Understand - Level 2):
Q. Explain the concept of gripper force in manipulators. How does understanding gripper force
contribute to the effective handling of objects in a robotic system?
The concept of gripper force in manipulators refers to the amount of force exerted by the gripper to
hold, manipulate, or grasp an object. It is a critical parameter in robotic systems as it directly
influences the system's ability to handle objects effectively. Understanding gripper force is
essential for the following reasons:
1. Object Handling and Stability:
o Gripper force is crucial for ensuring that the robotic system can securely hold and
manipulate objects of varying sizes and weights. The force exerted by the gripper
must be sufficient to maintain a stable grip on the object throughout the
manipulation process.
2. Adaptability to Object Properties:
o Different objects may have varying surface textures, shapes, and weights.
Understanding gripper force allows the robotic system to adapt its gripping force
based on the properties of the object being handled. For delicate or fragile objects,
the gripper force may need to be lower to avoid damage, while for heavier objects, a
higher gripper force may be required.
3. Preventing Slippage:
o Gripper force is essential in preventing slippage during object manipulation. If the
force is too low, the object may slip out of the gripper, leading to errors in the

19
handling process. On the other hand, if the force is too high, it may damage or
deform the object.
4. Energy Efficiency:
o Understanding the optimal gripper force contributes to energy efficiency in robotic
systems. Unnecessarily high gripping forces can lead to increased energy
consumption and wear on the gripper components. Optimizing the gripper force
ensures that the system operates efficiently while conserving energy.
5. Safety Considerations:
o Gripper force is also important from a safety perspective. Excessive force can pose a
risk, especially in environments where human-robot collaboration is present.
Ensuring that the gripper force is within safe limits minimizes the risk of injury or
damage in case of unintended contact.
6. Programming and Control:
o The ability to control and program the gripper force is essential for the robot
operator. This control allows for fine-tuning the robotic system's behavior based on
the specific requirements of different tasks and objects.
In summary, understanding gripper force is fundamental for effective object handling in a robotic
system. It ensures stability, adaptability, and safety during the manipulation process, contributing
to the overall efficiency and reliability of the robotic system.
Serial Manipulator (Remember - Level 1):
Q. Recall and name two characteristics of a serial manipulator. Provide a brief description of how
serial manipulators operate.
Ans: A serial manipulator is a type of robotic manipulator characterized by its serial chain
structure. Here are two key characteristics of serial manipulators along with a brief description of
how they operate:
1. Serial Chain Structure:
o Characteristic: A serial manipulator consists of a chain-like structure where each
link is connected in series, forming a sequential chain from the base to the end-
effector. The joints connecting the links allow rotational or translational motion, and
the end-effector is positioned at the end of the chain.
2. Sequential Movement:
o Characteristic: Serial manipulators operate in a sequential fashion, where each
joint or link in the chain moves one after the other to achieve the desired end-
effector motion. The movement is typically coordinated through the control of
individual joint angles or lengths, and the end-effector's final position is determined
by the cumulative effect of these sequential movements.
Description of Operation: In a serial manipulator, the movement of the end-effector is achieved
by changing the joint angles or lengths in a step-by-step manner. The control system determines the
desired position and orientation of the end-effector, and the individual joints are adjusted
sequentially to achieve this goal. The sequence of joint movements is often determined by

20
mathematical algorithms or control algorithms that take into account the kinematics of the
manipulator.
For rotational joints, the rotation angle is adjusted, while for prismatic joints, the length is altered.
The end result is that the end-effector follows a trajectory defined by the coordinated movements of
the individual joints. Serial manipulators are widely used in various applications, including
manufacturing, assembly, and pick-and-place tasks, due to their versatility and ability to reach into
confined spaces.
While serial manipulators offer flexibility and a wide range of motion, they may have limitations in
terms of speed, payload capacity, and precision, especially for complex tasks. These limitations are
often addressed through careful design considerations and advanced control strategies.
Parallel Manipulator (Understand - Level 2):
Q. Describe the key differences between serial and parallel manipulators. How does the design of a
parallel manipulator impact its performance?
Ans: Key Differences Between Serial and Parallel Manipulators:
1. Configuration:
o Serial Manipulator: In a serial manipulator, the links are arranged in a sequential
chain, and each link is connected in series from the base to the end-effector. The
movement is achieved by sequentially controlling each joint.
o Parallel Manipulator: In a parallel manipulator, multiple chains of links are
connected to a common end-effector platform. The movement is achieved through
the coordinated motion of these parallel chains.
2. Degrees of Freedom:
o Serial Manipulator: The degrees of freedom in a serial manipulator are determined
by the number of joints in the chain. Each joint adds one degree of freedom to the
system.
o Parallel Manipulator: The degrees of freedom in a parallel manipulator are
determined by the combination of degrees of freedom of each individual chain.
Parallel manipulators often exhibit a higher degree of kinematic redundancy.
3. Accuracy and Precision:
o Serial Manipulator: Serial manipulators are generally more accurate and precise
for tasks that require high precision. However, achieving high precision may involve
trade-offs in terms of speed and payload capacity.
o Parallel Manipulator: Parallel manipulators can provide high precision and
accuracy, especially in applications where the end-effector needs to maintain a
specific orientation. They are known for their stiffness, which contributes to
improved accuracy.
o Serial Manipulator: Serial manipulators may have limitations in terms of payload
capacity, especially for tasks that require lifting heavy loads. The payload capacity
is often limited by the strength of the individual links and joints.

21
o Parallel Manipulator: Parallel manipulators can offer higher payload capacities
due to the parallel arrangement of multiple chains. The load is distributed among the
parallel links, contributing to increased strength and stability.
5. Workspace:
o Serial Manipulator: Serial manipulators often have a larger workspace compared
to their parallel counterparts. The sequential arrangement of links allows for
extended reach.
o Parallel Manipulator: Parallel manipulators may have a more constrained
workspace compared to serial manipulators. However, they excel in applications
where a compact workspace is sufficient, and precision is crucial.
Impact of Design on Performance in Parallel Manipulators:
1. Stiffness:
o A well-designed parallel manipulator exhibits high stiffness, contributing to
improved accuracy and stability during operation.
2. Redundancy:
o The design of a parallel manipulator may incorporate kinematic redundancy,
allowing for multiple ways to achieve a specific end-effector position. This
redundancy can be exploited to optimize performance in terms of speed, accuracy,
or energy efficiency.
3. Actuation System:
o The choice of actuation system (hydraulic, pneumatic, electric) in the design affects
the performance in terms of speed, precision, and response time.
4. Control System:
o The control algorithms and strategies play a crucial role in the performance of a
parallel manipulator. Real-time control and feedback mechanisms contribute to
accurate and dynamic motion.
In summary, the key differences between serial and parallel manipulators lie in their configuration,
degrees of freedom, accuracy, payload capacity, and workspace. The design of a parallel
manipulator significantly impacts its performance, with considerations for stiffness, redundancy,
actuation, and control systems being critical factors.
Selection of Robot (Remember - Level 1):
Q. List and identify factors to consider when selecting a robot based on its application. Provide an
example scenario for each factor.
Selecting a robot based on its application involves considering various factors to ensure that the
chosen robot is well-suited for the specific task or operation. Here is a list of factors to consider
along with example scenarios for each:
o Factor: The maximum weight that the robot can carry or manipulate.

22
o Example Scenario: In an automotive assembly line, a robot needs to lift and
position heavy car parts like engine components or chassis. The payload capacity
should be sufficient to handle the weight of these parts.
2. Precision Requirements:
o Factor: The level of accuracy and precision needed for the task.
o Example Scenario: In electronics manufacturing, a robot is tasked with soldering
tiny components onto a circuit board. High precision is crucial to ensure accurate
placement and soldering of the components.
3. Speed and Cycle Time:
o Factor: The required speed of the robot and the time it takes to complete a cycle.
o Example Scenario: In a packaging line, a robot needs to quickly pick products
from a conveyor belt and place them into boxes. The robot's speed should match the
production rate to maintain efficiency.
4. Workspace Requirements:
o Factor: The physical area within which the robot needs to operate.
o Example Scenario: In a warehouse, a robot is tasked with moving and organizing
inventory on shelves. The robot's design and reach should be suitable for the spatial
constraints of the warehouse environment.
5. End-Effector (Tool) Compatibility:
o Factor: The type of end-effector or tool required for the specific task.
o Example Scenario: In a material handling application, a robot may need a gripper
to pick and place items, or a welding tool for an assembly line. The robot's
compatibility with the required end-effectors is crucial.
6. Flexibility and Adaptability:
o Factor: The ability of the robot to handle a variety of tasks or adapt to changes in
the production process.
o Example Scenario: In a research and development setting, a robot is used for
various experimental tasks. The robot should be programmable and easily adaptable
to different tasks without significant reconfiguration.
7. Environment:
o Factor: The operating environment, including temperature, humidity, and
cleanliness conditions.
o Example Scenario: In a food processing plant, a robot is involved in handling and
packaging food products. The robot should be designed to meet hygiene standards
and operate in a clean and food-safe environment.
8. Safety Considerations:
o Factor: Ensuring that the robot meets safety standards and can operate alongside
human workers safely.
o Example Scenario: In a collaborative manufacturing environment, a robot and
human workers share the workspace. The robot should have safety features such as
sensors and emergency stop mechanisms to prevent accidents.
9. Cost and Return on Investment (ROI):
o Factor: The overall cost of the robot and the expected return on investment over
time.
o Example Scenario: In a small-scale production facility, cost-effectiveness is a
priority. The chosen robot should provide the necessary functionality at a reasonable
cost, ensuring a positive return on investment.
10. Integration with Existing Systems:

23
o Factor: Compatibility with existing automation systems, control software, and
communication protocols.
o Example Scenario: In an industrial setting with an established manufacturing
system, a new robot should seamlessly integrate with existing machinery and
control systems to maintain workflow efficiency.
Considering these factors helps in selecting a robot that aligns with the specific requirements and
challenges of the application, ensuring optimal performance and efficiency in the intended
operational context.
Robot Application Scenarios (Understand - Level 2):
Q. Discuss how the type of gripper and manipulator selection is influenced by the specific
requirements of an application. Provide an example of a real-world application.
The selection of grippers and manipulators in robotics is highly influenced by the specific
requirements of an application. Different applications demand different functionalities, precision
levels, and adaptability. Here's a discussion on how the type of gripper and manipulator is
influenced by specific application requirements, along with a real-world example:
Gripper Selection:
1. Requirements for Gripper Force:
o Influence: The force exerted by the gripper must match the requirements of the application.
Delicate objects may require low force to avoid damage, while heavier or bulkier items may
need a higher gripping force for stability.
o Example: In an electronics assembly line, a gripper with adjustable force control may be
needed to delicately handle small and sensitive components without causing damage.
2. Type of Object to be Gripped:
o Influence: Grippers are designed for different types of objects, such as parallel jaw grippers
for simple objects, three-fingered grippers for irregular shapes, or vacuum grippers for flat
and smooth surfaces.
o Example: In a warehouse with various shaped packages, a robotic system may use a
versatile three-fingered gripper that can adapt to different package geometries.
3. Adaptive Gripper Design:
o Influence: For applications with a variety of objects, an adaptive gripper that can adjust its
shape or fingers to the object's form may be preferred.
o Example: In a logistics setting where the robot needs to handle packages of various shapes
and sizes, an adaptive gripper with compliant fingers or soft materials might be
advantageous.
Manipulator Selection:
1. Precision and Accuracy:
o Influence: Applications requiring high precision and accuracy, such as microelectronics
assembly or medical surgeries, may demand manipulators with precise control over joint
movements.
o Example: In a microelectronics assembly facility, a serial manipulator with high-precision
joints may be chosen to accurately position and place tiny components on circuit boards.

24
2. Speed and Efficiency:
o Influence: For applications with a need for high throughput or rapid movements, a
manipulator with high-speed capabilities is essential.
o Example: In an automotive manufacturing line, a parallel manipulator might be selected for
tasks like spot welding, where the speed of operation is critical to maintain production
efficiency.
o Influence: The size and shape of the workspace dictate the choice of manipulator. Serial
manipulators may be preferable in situations requiring an extensive reach, while parallel
manipulators may be more suitable for confined spaces.
o Example: In a narrow and confined environment like a pharmacy automation system, a
parallel manipulator may be selected to efficiently handle medications within a limited
workspace.
4. Collaborative vs. Industrial Setting:
o Influence: For applications where robots need to work alongside humans, collaborative
manipulators with safety features and sensors are crucial. In traditional industrial settings,
manipulators optimized for heavy-duty tasks may be preferred.
o Example: In a manufacturing facility where human-robot collaboration is essential, a
collaborative robot (cobot) with force-limiting capabilities might be selected for tasks like
assembly alongside human workers.
In summary, the selection of grippers and manipulators is highly application-specific. The gripper
and manipulator chosen must align with the specific needs of the task at hand, considering factors
such as force requirements, adaptability, precision, speed, workspace constraints, and the
collaborative nature of the working environment. The choice directly impacts the efficiency,
productivity, and overall success of the robotic system in a given application.
Gripper Types (Remember - Level 1):
Q. Name and list two different types of grippers used in robotics. Briefly describe the advantages
and disadvantages of each type.
There are various types of grippers used in robotics, each designed for specific applications. Here
are two different types of grippers along with their advantages and disadvantages:
1. Parallel Jaw Gripper:
o Advantages:
 Simple Design: Parallel jaw grippers have a straightforward design with two
opposing jaws that move parallel to each other.
 Versatility: They are versatile and can handle a wide range of object shapes
and sizes.
 High Precision: Parallel jaw grippers can provide high precision in gripping
tasks, making them suitable for applications where accuracy is crucial.
o Disadvantages:
 Limited Grasping Geometry: The parallel nature of the jaws can limit the
gripper's ability to grasp objects with irregular shapes or contours.
 Limited Dexterity: Compared to more complex gripper designs, parallel
jaw grippers may have limitations in terms of dexterity and adaptability to
complex objects.

25
2. Vacuum Gripper:
o Advantages:
 Suitable for Flat Surfaces: Vacuum grippers excel at handling flat and
smooth objects, such as sheets of paper, glass, or metal.
 Non-Damaging: Vacuum grippers are non-contact devices, which makes
them suitable for delicate or sensitive objects that should not be subjected to
mechanical forces.
 High Speed: They can operate at high speeds, making them efficient for
applications with a need for rapid pick-and-place operations.
o Disadvantages:
 Limited to Flat Objects: Vacuum grippers are most effective with flat and
non-porous surfaces, limiting their suitability for irregularly shaped or
porous objects.
 Dependency on Surface Conditions: The effectiveness of vacuum grippers
can be affected by surface conditions, such as dust, moisture, or uneven
surfaces.
 Requires a Vacuum Source: The operation of vacuum grippers necessitates
a vacuum source, adding complexity to the system and requiring additional
equipment.
It's important to note that the selection of a gripper type depends on the specific requirements of the
application. Engineers and roboticists often choose grippers based on factors such as the nature of
the objects to be handled, the required precision, speed considerations, and the overall design of the
robotic system. Integrating grippers with complementary features can enhance the overall
versatility and performance of a robotic system.
Manipulator Selection Criteria (Understand - Level 2):
Q. Explain the importance of considering application-specific requirements in the selection of a
manipulator. How does this understanding impact the efficiency and effectiveness of the robotic
system?
Considering application-specific requirements in the selection of a manipulator is crucial for
ensuring that the robotic system meets the unique demands and challenges of a given task. The
importance of this consideration lies in how well the manipulator can perform its intended
functions within the context of the application. Here's why it's vital and how it impacts the
efficiency and effectiveness of the robotic system:
Importance of Considering Application-Specific Requirements:
1. Precision and Accuracy:
o Importance: Some applications require high precision and accuracy, such as tasks in
electronics assembly or medical surgeries. The manipulator's ability to precisely position
the end-effector is critical for successful operations.
o Impact: If a manipulator lacks the required precision, it may result in errors, defective
products, or compromised outcomes in applications that demand accuracy.
2. Speed and Throughput:

26
o Importance: Certain applications, like manufacturing and assembly lines, may prioritize
high-speed operations to meet production targets and optimize efficiency.
o Impact: Choosing a manipulator that aligns with the desired speed requirements ensures that
the robotic system can achieve the necessary throughput, contributing to overall production
efficiency.
o Importance: Different tasks involve handling objects of varying sizes and weights. The
manipulator's payload capacity must match the demands of the application to ensure stable
and safe operation.
o Impact: Selecting a manipulator with inadequate payload capacity may lead to mechanical
failures, reduced lifespan, or safety hazards if the system is required to handle loads beyond
its capability.
o Importance: The physical space in which the manipulator needs to operate can vary widely.
Some applications require extended reach, while others may operate in confined spaces.
o Impact: Choosing a manipulator with an appropriate workspace ensures that it can reach all
necessary locations, preventing limitations that may hinder the system's ability to perform
tasks effectively.
5. Collaborative or Industrial Setting:
o Importance: In collaborative environments where robots work alongside humans, safety
features and compliance with industry standards are critical. In traditional industrial
settings, manipulators optimized for heavy-duty tasks may be preferred.
o Impact: Failing to consider the collaborative nature of the workspace may pose safety risks
in human-robot interaction scenarios, affecting both the efficiency and safety of the robotic
system.
6. Flexibility and Adaptability:
o Importance: Some applications require robots to handle various tasks or adapt to changes in
the production process. Flexibility in the manipulator's design and control is essential in
such cases.
o Impact: An adaptable manipulator can enhance the system's versatility, allowing it to
efficiently switch between different tasks or adapt to changes in production requirements.
Impact on Efficiency and Effectiveness of the Robotic System:
1. Task Optimization:
o Considering application-specific requirements ensures that the manipulator is optimized for
the specific tasks it needs to perform. This optimization directly impacts the efficiency of
task execution.
2. Resource Utilization:
o A well-matched manipulator maximizes the utilization of resources, including time and
energy. It allows the robotic system to operate efficiently and effectively in line with the
demands of the application.
3. Reduced Downtime and Errors:
o The right manipulator minimizes downtime and reduces the likelihood of errors. Tasks are
executed with precision, leading to fewer interruptions and improved overall system
reliability.
4. Enhanced Safety:
o In collaborative settings, considering safety requirements ensures the well-being of human
workers. This, in turn, contributes to the overall effectiveness of the robotic system by
creating a secure and collaborative work environment.
5. Cost-Effectiveness:

27
o Proper selection based on application-specific needs prevents unnecessary investments in
features that are not essential for the task. This contributes to the cost-effectiveness of the
robotic system.
6. Adaptability to Changes:
o An understanding of application-specific requirements allows the robotic system to adapt to
changes efficiently. Whether there are modifications in the production process or new tasks
are introduced, the manipulator can respond effectively.
In summary, considering application-specific requirements when selecting a manipulator is
paramount for optimizing the efficiency and effectiveness of a robotic system. It ensures that the
chosen manipulator is well-suited for the intended tasks, leading to improved performance,
reliability, and overall success in meeting the goals of the application.

INDUSTRIAL ROBOTICS Module- II.pdf

Recommended

Recommended

More Related Content

Similar to INDUSTRIAL ROBOTICS Module- II.pdf

Similar to INDUSTRIAL ROBOTICS Module- II.pdf (20)

Recently uploaded

Recently uploaded (20)

INDUSTRIAL ROBOTICS Module- II.pdf