Module 1 Lecture 1 Introduction To Automation In Production Systems.ppt

MT308 Industrial Automation
Mechatronics Engineering Department
Faculty of Engineering
Sana’a University
Dr. Khalil A. Al-Hatab

Week # Module Name Lecture # & Heading Reading Sections
1-3
Module 1: Introduction and Basic Concept
of Automation
Lecture 1: introduction & Basic Concept of
Automation
Ch. 1 & Ch. 4
Lecture 2: Components & Applications of
Automation System
Ch1*
Lecture 3: Overview of Manufacturing:
Operations, Metrics and Economics
Ch. 2 & Ch. 3
4
Module 2: Mechanical System:
Components, Dynamics & Modeling
Lecture1: Mechanical System: Components,
Dynamics & Modeling
Ch3*
5 Module 3: Industrial Control Systems Lecture1: Industrial Control Systems Ch. 6 & Ch5*
6-10
Module 4: Hardware Components
for Automation
Lecture1-2: Automation Sensory Devices Ch. 6 & Ch5*
Lecture3-4: Control of Actuators in Automation
Mechanisms
Ch. 6 & Ch4*
Lecture5: Digital Data Acquisition (DDA) Ch. 6
10-14 Module 5: Industrial Automation Systems
Lecture1: Design an Example for Industrial
Automation System
Ch6*
Lecture2-3: Numerical Control Ch. 7
Lecture4: Material Handling & Identifications Ch. 10-Ch. 12
Lecture5: Single-Station Manufacturing Cells Ch. 13 & Ch. 14
15 Review for Final Exam
*: Industrial Automation: An Engineering Approach
2
Brief Course Contents

Course Information
 Instructor
 Associate Professor Dr. Khalil Al-Hatab, (PhD)
 k.alhatab@eng-su.edu.ye
 Time and place
 Lecture: Monday 8-12, xxx Wed. 8-10d. 10-12
 Lab (class & practicing): Lab 2 Wed. 12-2
 Grading Policy
 Homework & Attendance: 10%
 Quizzes: 10%
 Labs: 10%
 Mid-term: 30%
 Mini-Projects 10%
 Final Exam: 30%
 Textbook
1. Mikel P. Groover, Automation, Production Systems, and Computer-Integrated Manufacturing,
4th ed., Pearson Higher Education, 2015.
2. Lecture Notes: Industrial Automation: An Engineering Approach, JM 608 INDUSTRIAL
AUTOMATION, Politeknik Port Dickson, 2013 3

Module 1 - Lecture 1:
Introduction To
Automation In Production
Systems
©2008 Pearson Education, Inc., Upper Saddle River, NJ. All rights reserved. This material is protected under all copyright laws as they currently exist.
No portion of this material may be reproduced, in any form or by any means, without permission in writing from the publisher. For the exclusive use of adopters of the book
Automation, Production Systems, and Computer-Integrated Manufacturing, Third Edition, by Mikell P. Groover. 4

Module 1 - Lecture 1: Introduction To
Automation In Production Systems
Sections:
 Definitions & Overview of Industrial Automation
 Production Systems
 Automation in production systems
 Manual Labor in Production Systems
 Types of Automation
 Basic Elements of an Automated System
 Control System
 Advanced Automation Functions
 Reason for automated and not automated
 Automation Principles and Strategies
 Levels of Automation

Objectives:
• Upon completion of this course, students should be able to:-
 To explain the definition and classification of automation in
industry of automation in industry
 Explain the basic concept of automation terminology
 To classify the element of automation function and level
 To define the reason of automation.
 Explain the positioning concept of automation

Definition of industrial automation
Automation refers to a technology which based on the usage of mechanical,
electronic and computer system in handling process and manufacturing process
control. The usage of automation technology started when work done by labor/worker
was started replace by machine. Technology development process continuous
improve until human started introduce the usage of robotic, CAD/CAM, Flexible
manufacturing system (FMS) and others technology to increase human quality of life
and increase productivity in the industrial.
Industrial: In a general sense the term “Industry” is defined as follows: Systematic
Economic Activity that could be related to Manufacture/Service/ Trade. In this
course, we shall be concerned with Manufacturing Industries only.
Automation: The word ‘Automation’ is derived from Greek words “Auto”(self) and
“Matos” (moving). Automation therefore is the mechanism for systems that “move
by itself”. However, apart from this original sense of the word, automated systems
also achieve significantly superior performance than what is possible with manual
systems, in terms of power, precision and speed of operation.

Automation is a set of technologies that results in operation of machines and
systems without significant human intervention and achieves performance superior
to manual operation
A Definition from Encyclopedia Britannica: The application of machines to tasks
once performed by human beings or, increasingly, to tasks that would otherwise be
impossible. Although the term mechanization is often used to refer to the simple
replacement of human labor by machines, automation generally implies the
integration of machines into a self-governing system.
From Wikipedia: Automation, is the use of various control systems for operating
equipment such as machinery, processes in factories, boilers and heat treating ovens,
switching in telephone networks, steering and stabilization of ships or aircraft and
other applications with minimal or reduced human intervention.
Some processes have been completely automated. Although saving labor is a
common objective, automation is also used to save energy and materials and improve
quality, accuracy and precision.

From this course: Automation can be defined as the technology by which a
process or procedure is accomplished without human assistance.
Mechanization refers to the use of machinery (usually powered) to assist or replace
human workers in performing physical tasks, but human workers are still required
to accomplish the cognitive and sensory elements of the tasks. By contrast,
automation refers to the use of mechanized equipment that performs the physical
tasks without the need for oversight by a human worker.

OVERVIEW OF INDUSTRIAL
AUTOMATION
1950s, manufacturing operations used traditional machinery:
 lacked flexibility,
 required high skilled labor,
 have to retooled the machinery on each different product
manufactured,
 the movement of materials have to be rearranged,
 product with complex shapes required trial and error attempts by
the operator in order to set the proper processing parameters on the
machine,
 time-consuming
 labor cost and production cost increase.

AUTOMATION
 How to improve PRODUCTIVITY? By
MECHANIZATION. Operation runs with the use of
various mechanical, hydraulic, pneumatic, or electrical
devices.
 But still operator have to control the process and check
the machine’s performance, thus to IMPROVE THE
EFFICIENCY of manufacturing process =
AUTOMATION.

AUTOMATION

AUTOMATION
 An automated system is a collection of devices working
together to accomplish tasks or produce a product or family of
products.
 Industrial automated systems can be one machine or a group of
machines called a cell.
 The term “programmable automation technology” actually
refers to three individually distinct technologies that have a
common thread: programmability. These technologies are
computer numerical control (CNC) technology, robotics
technology, and programmable logic control (PLC).

The Realities of Modern Manufacturing
 Globalization - Once underdeveloped countries (e.g., China,
India, Mexico) are becoming major players in manufacturing
 International outsourcing - Parts and products once made in
the United States by American companies are now being made
offshore (overseas) or near-shore (in Mexico and Central
America)
 Local outsourcing - Use of suppliers within the U.S. to provide
parts and services

More Realities of Modern Manufacturing
 Contract manufacturing - Companies that specialize
in manufacturing entire products, not just parts, under
contract to other companies
 Trend -toward the service sector (economy)
 Quality expectations - Customers, both consumer and
corporate, demand products of the highest quality
 Need for operational efficiency - manufacturers must
be efficient in in their operations to overcome the labor
cost advantage of international competitors

Modern Manufacturing
Approaches and Technologies
 Automation - automated equipment instead of labor
 Material handling technologies - because manufacturing
usually involves a sequence of activities
 Manufacturing systems - integration and coordination of
multiple automated or manual workstations
 Flexible manufacturing - to compete in the low-
volume/high-mix product categories
 Quality programs - to achieve the high quality expected by
today's customers
 CIM - to integrate design, production, and logistics
 Lean production - more work with fewer resources

Manual Labor in Production
Systems
Is there a place for manual labor in the modern
production system?
 Answer: YES
 Two aspects:
1. Manual labor in factory operations
2. Labor in manufacturing support systems

Manual Labor in Factory
Operations
 The long term trend is toward greater use of automated systems to
substitute for manual labor.
 When is manual labor justified?
 Some countries have very low labor rates and automation
cannot be justified
 Task is too technologically difficult to automate
 Short product life cycle
 Customized product requires human flexibility
 To cope with ups and downs in demand
 To reduce risk of product failure
 Lack of capital.

Labor in Manufacturing
Support Systems
 Product designers who bring creativity to the design
task
 Manufacturing engineers who
 Design the production equipment and tooling, and
 Plan the production methods and routings
 Equipment maintenance
 Programming and computer operation
 Engineering project work
 Plant management

Production System Defined
 Production System is a collection of people,
equipment, and procedures organized to accomplish
the manufacturing operations of a company
Two categories:
 Facilities – the factory and equipment in the facility
and the way the facility is organized (plant layout)
 Manufacturing support systems – the set of
procedures used by a company to manage production
and to solve technical and logistics problems in
ordering materials, moving work through the factory,
and ensuring that products meet quality standards

The Production System
Fig. 1.1

Production System Facilities
 Facilities - include the factory, production machines and
tooling, material handling equipment, inspection equipment,
and computer systems that control the manufacturing operations.
 Plant layout – the way the equipment is physically arranged in
the factory
 Manufacturing systems – logical groupings of equipment and
workers in the factory
 Production line: More complex manufacturing systems
consist of collections of machines and workers.
 Stand-alone workstation and worker

Manufacturing Systems
 Three categories in terms of the human participation in the processes
performed by the manufacturing system:
1. Manual work systems - a worker performing one or more tasks
without the aid of powered tools, but sometimes using hand tools
(i.e. A quality control inspector using a micrometer to measure the
diameter of a shaft)
2. Worker-machine systems - a worker operating powered
equipment. A combinations of one or more workers and one or
more pieces of equipment (i.e. A machinist operating an engine
lathe to fabricate a part for a product)
3. Automated systems - a process performed by a machine without
direct participation of a human. Automation is implemented using
a program, control system & Power. Two levels of automation can
be identified: semiautomated and fully automated.

Manual Work System
Fig. 1.2 (a)

Worker-Machine System
Fig. 1.2 (b)

Automated System
Fig. 1.2. (c)

Manufacturing Support Systems
 Involves a cycle of information-processing activities that consists of four
functions:
1. Business functions - sales and marketing, order entry, cost accounting, customer
billing
2. Product design - research and development, design engineering, prototype shop
3. Manufacturing planning - The information and documentation that constitute
the product design flows into the manufacturing planning function. The
information- processing activities in manufacturing planning include: process
planning, master scheduling, material requirements planning, and capacity
planning.
4. Manufacturing control - is concerned with managing and controlling the
physical operations in the factory to implement the manufacturing plans. The
flow of information is from planning to control. Included in this function are
shop floor control, inventory control & quality control

Information Processing Cycle in
Fig. 1.3

Automation in Production Systems
• In an industrial context, we can define automation as a
technology that is concerned with the application of mechanical,
electronic and computer based systems to operate and control
production process.
• Examples of industries for automation:
 Manufacturing (e.g. on factory shop floors)
 Services (e.g. voice menus for banks)
 Transport (e.g. planes, ships, cars)
 Process control (e.g. nuclear/electrical power stations, chemical
plants)
 Offices (e.g. word processing, spreadsheets, photocopying, email)

 Automation and robots are two closely related technologies. Both are
connected with the use and control of production operations. Automation is a
technology dealing with the application of mechatronics and computers for
production of goods and services.
 Example of this technology in Automated Manufacturing System
includes:
 Transfer lines that perform a series of machining operation
 Mechanical assembly machines
 Feedback control systems
 Numerically controlled machine tools
 Logistic support tools
 Automated inspection system for quality control
 Automated material handling system and storage system to integrate
manufacturing operation
 CAD/CAM system and robots- robots are mechatronic devices that
assist industrial automation.

 The automated elements of the production system can be
separated into two categories:
1. Automation of manufacturing systems in the factory
2. Computerization of the manufacturing support systems
 In modern manufacturing systems, the two categories overlap
because the automated manufacturing system operating on the
factory floor are often implemented by computer systems; and
connected to the computerized manufacturing support system
and management information system operating plant and
enterprise level.
 Computer-Integrated Manufacturing (CIM)

Automated Manufacturing Systems
• In an industrial context, we can define automation as a technology that
is concerned with the use of mechanical, electrical /electronic and
computer based system to control production process.
• Examples of this technology include:
• Transfer lines that perform a series of machining operation
• Automated assembly systems
• Feedback control systems
• Numerically controlled machine tools
• logistic support tools
• Automatic inspection system for quality control
• Automated material handling system and storage system to integrate
manufacturing operations
• Industrial robots (CAD/CAM system and robots- robots) that perform
processing or assembly operations.

Computer Integrated
Manufacturing (CIM)
Fig. 1.4

Objectives of Computerized
 To reduce the amount of manual and clerical effort in product design,
manufacturing planning and control, and the business functions.
 Computer technology is used to implement automation of the manufacturing
systems in the factory.
 CIM (computer integrated manufacturing) denotes the pervasive use of computer
system to design the products, plan the production, control the operations, and
perform the various business-related functions in one system that operates
throughout the enterprise.
 CIM includes CAD/CAM and the business functions of the firm
 Integrates computer-aided design (CAD) and computer-aided manufacturing
(CAM) in CAD/CAM. CAD denotes the use of computer systems to support the
product design function. CAM denotes the use of computer systems to perform
function related to manufacturing engineering such as process planning and
numerical control part programming.

Automated Manufacturing Systems
Three basic types:
1. Fixed automation
2. Programmable automation
3. Flexible automation

Fixed Automation
 Fixed Automation is a manufacturing system in which the sequence of
processing (or assembly) operations is fixed by the equipment
configuration. The operation are usually simple, it used with high
demand rates and inflexible product design.
 Typical features:
 Suited to high production quantities
 High initial investment for custom-engineered equipment
 High production rates.
 It is therefore appropriate to design specialized equipment to
process products at high production rates and low cost (custom-
engineered with special purpose equipment to automate a fixed
sequence of operation
 Relatively inflexible in accommodating product variety

Fixed Automation
• A good example of fixed automation can be found in the automobile
industry, where highly integrated transfer lines are used to perform
machining operation on engine and transmission component.
• The economics of fixed automation is such that the cost of the special
equipment can be divided over a large number of units produced, so that
the resulting units cost can be lower relative to alternative method of
production.
• The risk encountered with fixed automation is that the initial investment
cost is high and if the volume of production turns out to lower than
anticipated, then the unit costs become greater.
• Another problem with fixed automation is that the equipment is specially
designed to produce only one product and after that product’s life cycle
is finished, the equipment is likely to become obsolete. Therefore, for
products with short life cycles, fixed automation is not economical.

Programmable Automation
 A manufacturing system designed with the capability to change the sequence of
operations to accommodate different product configurations.
 The operation sequence is controlled by a program which is a set of instructions
coded so that they can be read and interpreted by the system. New programs can
be prepared and entered into the equipment to produce new products.
 The physical setup of the machine must also be changed, tools must be loaded.
Fixtures must be attached to the machine table and the required machine setting
must be entered. This change over procedure takes time.
 Typical features:
 High investment in general purpose equipment. The production equipment is
designed to be adaptable to variations in a product configuration.
 Lower production rates than fixed automation
 Flexibility to deal with variations and changes in product configuration
 Most suitable for batch production
 Physical setup and part program must be changed between jobs (batches)

Programmable Automation
• This adaptability feature is accomplished by operating the equipment under the control of
a “program” of instructions that has been prepared especially for a given product.The
program is read into the production equipment and the equipment performs that particular
sequence of operations to make that product.
• The system must be reprogrammed with the set machine instructions that correspondent to
the new product when a new batch of different product needs to produce. Physical setup of
the machine must be changed:
 Tool must be loaded
 Fixtures must be attached to the machine table
 Required machine setting must be entered.
• In terms of economics, the cost of the programmable equipment can be spread over a large
number of products even though the products are different. Because of the programming
feature and the resulting adaptability of the equipment, may different and unique products
can be processed economically in small batches (batches production and medium volume).
 Example : SMT production line in PCBA manufacturing
- SMT – Surface Mount Technology
- PCBA – Printed Circuit Board Assembly

Flexible Automation
 Flexible Automation is an extension of programmable automation in
which the system is capable of changing over from one job to the next
with no lost time between jobs.
• There is no lost production time while reprogramming the system and
altering the physical combination and schedules of parts or products
instead of requiring that they be made in batches.
• It is designed to manufacture a variety of product or parts with low
production rates, varying product design and demand.
Typical features:
 High investment for custom-engineered system
 Continuous production of variable mixes of products
 Medium production rates
 Flexibility to deal with soft product variety

Flexible Automation
• This type of automation is most suitable for the mid-volume
production range. Flexible automation possesses some of the features
of both fixed and programmable automation. Other terms used for
flexible automation include FMS and CIM.
• Flexible automation typically consists of a series of workstations that
are interconnected by material-handling and storage equipment to
process different product configurations at the same time on the same
manufacturing system.
• A central computer is used to control the various activities that occur
in the system, routing the various parts to the appropriate stations and
controlling the programmed operations at the different stations.
• One of the features that distinguish programmable automation from
flexible automation is that with programmable automation the
products are made in batches. When one batch is completed, the
equipment is reprogrammed to process the next batch. (Flex. Auto
can produce one of a kind, batches not required)

Flexible Automation
• With flexible automation, different products can be made at the same
time on the same system. This feature allows a level of versatility
that is not available in pure programmable automation.
• This means that products can be produced on a flexible system in
batches, if desirable, or that several products can mix on the same
system. The computational power of the control computer is what
makes this versatility possible.
• Flexible Automation advantages:
1. Increased speed and productivity.
2. Reduced manual labor.
3. Improved consistency.
4. Greater reliability.
5. Greater accuracy and consistency.
6. Reduced cost of assembly

Automation Comparison
Automation When to consider Advantages Disadvantages
Fixed - High demand
volume,
- Long product life
cycles
- Maximum
efficiency
- Low unit cost
- Large initial
investment
- Inflexibility
Programmable - Batch
production,
- Product with
different options.
- Flexibility to deal
with changes in
product.
- Low unit cost for
large batches.
-New products
requires long setup
time.
- High unit cost
relative to fixed
automation.
Flexible - Low production
rates.
- Varying demand.
- Short product life
cycles.
- Flexibility to deal
with designs
variations.
- Customized
products.
- Large initial
investment .
- High unit cost or
programmable
automation.

Product Variety and Production
Quantity for Three Automation Types
Fig. 1.5

Elements of an Automated System

1) Power to accomplish the automated process
2) Program Instruction
3) Control System
1) Power to accomplish the automated process
• An automated system is used to operate some process and power
is required to drive the process as well as the controls.
• The principal source of power is electricity:
 Available at moderate cost.
 Can be readily converted to alternative energy forms (mechanical,
thermal, light, acoustic, hydraulic and pneumatic).
 Low level power can be used to accomplish functions such as signal
transmission, information processing and data storage and
communication.
 Can be stored in long-life batteries for use in remote locations
Basic Elements of An Automated System

a) Power for the Process
 The term ‘process’ refers to the manufacturing operation that is
performed on work unit as follows:
 Material handling functions:
Loading and unloading the work unit
Material transport between operations
Manufacturing process and their power requirements

b) Power for Automation
• Controller unit:Need electrical power to read the program
of instructions, calculations and execute the instructions by
transmitting the proper commands to actuating devices.
• Power to actuate the control signals:Controller sent the
commands by means of low-voltage control signal to provide
the proper power level for actuating device (motor).
• Data acquisition and information processing: Keeping the
records of process performance or product quality.

2) Program of instructions
The action performed by an automated process are defined by a program of
instructions. Whether the manufacturing operation involves low, medium or high
production, each part require one or more processing steps performed during the
work cycle.
Program is a set of commands that specify the sequence of steps in the work
cycle and the details of each step. The set point is the value of the process
parameter or desired value of the controlled variable in the process.
 Work cycle programs
• The simplest automated processes, the work cycle consists of 1 step (set
point control). The more complicated systems consist of multiple steps.
• The process parameter changes in each step. A process parameter is an input
to the process, whereas a process variable is the corresponding output of the
process.
 Decision making in the Programmed Work Cycle
• Each work cycle consists of the same steps and associated process changes
with no variation from one cycle to the next.
• Operator interaction Different part or product styles are processed by the
system  Variations in the starting work unit.

50
Work Cycle programs
 In the simplest automated processes, the work cycle consists of essentially one
step, which is to maintain a single process parameter at a defined level. It is
assumed that loading and unloading of the work units into and from the furnace
is performed manually and is therefore not part of the automatic cycle.
 Process parameter : is an input to the process, such as the temperature dial
setting.
 Process variable: is the corresponding output of the process, which is the actual
temperature of the furnace
 During each step, there are one or more activities involving changes in one or
more process parameters
 Examples of process parameters include: desired coordinate axis value in a
positioning system, valve open or closed in a fluid flow system, and motor on
or off.
 Examples of corresponding process variables include the actual position of the
coordinate axis, flow rate of fluid in the pipe, and rotational speed of the
motor.

Five Categories Of Work
Cycle Programs
 Set-point control, in which the process parameter value is constant during the work
cycle (as in the furnace example).
 Logic control, in which the process parameter value depends on the values of other
variables in the process.
 Sequence control, in which the value of the process parameter changes as a function of
time. The process parameter values can be either discrete (a sequence of step values) or
continuously variable.
 Interactive program, in which interaction occurs between a human operator and the
control system during the work cycle.
 Intelligent program, in which the control system exhibits aspects of human intelligence
(e.g., logic, decision making, cognition, learning) as a result of the work cycle program.
 A work cycle consisting of multiple steps that are repeated with no deviation from one
cycle to the next. Most discrete part manufacturing operations are in this category. A
typical sequence of steps (simplified) is the following: (1) load the part into the
production machine, (2) perform the process, and (3) unload the part. During each step,
there are one or more activities that involve changes in one or more process parameters.
51

Example 4.1 An Automated
Turning Operation
Consider an automated turning operation that generates a cone-shaped product The system
is automated and a robot loads and unloads the work units. The work cycle consists of the
following steps: (1) load starting workpiece, (2) position cutting tool prior to turning, (3)
turn, (4) reposition tool to a safe location at end of turning, and (5) unload finished
workpiece. Identify the activities and process parameters for each step of the operation.
Solution:
Automation, Production Systems, and Computer-Integrated Manufacturing, Third Edition, by Mikell P. Groover. 52/20
Process parameters
Activities
step #
axis values, gripper value (open or closed),
chuck jaw value (open or closed).
reaching, lifting and positioning the raw work
part, then retreating to safe position.
(1) Robot
manipulator
x- and z-axis position of the tool.
movement to a “ready” position.
(2) cutting tool
speed (rev/min), (mm/rev), radial distance
(changed continuously at a constant rate
/revolution) For a consistent finish on the
surface, the rotational speed must be
continuously adjusted to maintain a constant
surface speed (m/min)
workpiece rotation, cutting tool feed &
position, cut the conical shape, finishing
operation (multiple turning passes).
(3) turning
operation
process parameters are the same.
are the reverse of steps (2) and (1), respectively
4
5

Decision-Making in a
Programmed Work Cycle
 The two features of the work cycle were:
(1) The number and sequence of processing steps and
(2) The process parameter changes in each step.
 The following are examples of automated work cycles in which
decision making is required:
 Operator interaction (input data)
 Automated teller machine
 Different part or product styles processed by the system
 Robot welding cycle for two-door vs. four door car models
 Variations in the starting work units
 Additional machining pass for oversized sand casting

54
Features of a Work Cycle
Program
The following summarizes the features of work cycle programs (part programs)
used to direct the operations of an automated system:
1. Number of steps in the work cycle: A general sequence in discrete
production operations is (1) load, (2), process, (3) unload, but the process
may include multiple steps.
2. Manual participation in the work cycle (e.g., loading and unloading
workparts)
3. Process parameters - How many process parameters must be controlled
during each step? Are the process parameters continuous or discrete? Do
they change during the step?
4. Operator interaction - does the operator enter processing data?
5. Variations in part or product styles
6. Variations in starting work units - some adjustments in process
parameters may be required to compensate for differences in starting units

Control System – Two Types
 The control system causes the process to accomplish its defined
function, which is to perform some manufacturing operation.
 The control element of the automated system executes the program
of instructions.
1. Closed-loop (feedback) control system – a system in which the
output variable is compared with an input parameter, and any
difference between the two is used to drive the output into
agreement with the input
2. Open-loop control system – operates without the feedback loop, so
no comparison is made between the actual value of the output and the
desired input parameter.
 Simpler and less expensive
 Risk that the actuator will not have the intended effect

Closed-loop (Feedback)
Control System
1. The input parameter (i.e., set point) represents the desired value of the output.
2. The process is the operation or function being controlled.
3. The output variable (process variable) that is being controlled in the loop, perhaps a critical performance
measure in the process, such as temperature or force or flow rate.
4. A sensor is used to measure the output variable and close the loop between input and output. Sensors perform
the feedback function in a closed-loop control system.
5. The controller compares the output with the input and makes the required adjustment in the process to reduce
the difference between them.
6. The adjustment is accomplished using one or more actuators, which are the hardware devices that physically
carry out the control actions, such as electric motors or flow valves.
56/75
Figure 4.3 shows only one loop. Most industrial processes require multiple
loops, one for each process variable that must be controlled

Open-Loop Control System
 In this case, the controls operate without measuring the
output variable.
 The controller relies on an accurate model of the effect of
its actuator on the process variable.
 With an open-loop system, there is always the risk that the
actuator will not have the intended effect on the process,
and that is the disadvantage of an open-loop system. Its
advantage is that it is generally simpler and less expensive
than a closed-loop system.

Positioning System Using
Feedback Control
A one-axis position control system consisting of a leadscrew driven by
a servomotor and using an optical encoder as the feedback sensor.
For the open-loop case, the diagram for the positioning system would be similar to the
preceding, except that no feedback loop is present and a stepper motor would be used in place
of the dc servomotor. A stepper motor is designed to rotate a precise fraction of a turn for each
pulse received from the controller. Since the motor shaft is connected to the leadscrew, and the
leadscrew drives the worktable, each pulse converts into a small constant linear movement of
the table. To move the table a desired distance, the number of pulses corresponding to that
distance is sent to the motor. Given the proper application, whose characteristics match the
preceding list of operating conditions, an open-loop positioning system works with high reliability.

When to Use an
Open-Loop Control System
Open-loop systems are usually appropriate when the following
conditions apply:
 Actions performed by the control system are simple
 Actuating function is very reliable
 Any reaction forces opposing the actuation are small enough as
to have no effect on the actuation
 If these conditions do not apply, then a closed-loop control
system should be used

Advanced Automation
Functions
 In addition to executing work cycle programs, an automated system may be
capable of executing advanced functions that are not specific to a particular work
unit. Advanced automation functions include the following: (1) safety
monitoring, (2) maintenance and repair diagnostics, and (3) error detection
and recovery, are made possible by special subroutines included in the program of
instructions.
 Safety Monitoring: is the use of sensors to track the system's operation and
identify conditions that are unsafe or potentially unsafe.
 Reasons for safety monitoring: To protect workers and equipment
 Possible responses to hazards:
 Complete stoppage of the system
 Sounding an alarm
 Reducing operating speed of process
 Taking corrective action to recover from the safety violation

1) Safety Monitoring
• An automated system is often installed to perform a potentially dangerous operation that
would otherwise be accomplished manually. Two reasons for providing an automated
system with a safety monitoring capability:
a) To protect human workers in the vicinity of the system
b) To protect the equipment associated with the system
 Example: Emergency stop buttons, Limit switches, photoelectric sensors, temperature
sensors, heat or smoke detectors, pressure-sensitive floor pads and machine vision
systems.
2) Maintenance and repair diagnostics: Three modes of operation are typical of a
modern maintenance and repair diagnostics subsystem:
 Status monitoring: To monitor and record the status of key sensors and parameter of the
system during normal operation.
 Failure diagnostics: The failure diagnostics mode is invoked when a malfunction or
failure occurs.
 Recommendation of repair procedure: The subsystem provides a recommendation
procedure to the repair crew as to the steps that should be taken to effects repairs.
 Status monitoring serves two important functions in machine diagnostics: (1) providing
information for diagnosing a current failure and (2) providing data to predict a
future malfunction or failure
Advanced Automation Functions

Advanced Automation
Functions
3) Error Detection and Recovery:
 Error detection – in analyzing a given production operation, the possible errors can be
classified into one of three general categories:
1. Random errors, occur when the process is in statistical control. Large variations in part
dimensions, even when the production process is in statistical control, can cause problems
in downstream operations.
2. Systematic errors, are those that result from some assignable cause such as a change in raw
material or drift in an equipment setting.
3. Aberrations errors that results from either an equipment failure or a human mistake
 Functions:
 Use the system’s available sensors to determine when a deviation or malfunction has
occurred
 Correctly interpret the sensor signal
 Classify the error
 The two main design problems in error detection are (1) anticipating all of the possible
errors that can occur in a given process, and (2) specifying the appropriate sensor systems
and associated interpretive software so that the system is capable of recognizing each error

Advanced Automation
Functions
 Error recovery – is concerned with applying the
necessary corrective action to overcome the error
and bring the system back to normal operation.
 Possible strategies:
 Make adjustments at end of work cycle
 Make adjustments during current work cycle
 Stop the process to invoke corrective action
 Stop the process and call for help

Reasons for Automating
Companies undertake projects in automation and computer-integrated
manufacturing for good reasons, some of which are the following:
1. To increase labor productivity
2. To reduce labor cost
3. To mitigate the effects of labor shortages
4. To reduce or remove routine manual and clerical tasks
5. To improve worker safety
6. To improve product quality
7. To reduce manufacturing lead time
8. To accomplish what cannot be done manually
9. To avoid the high cost of not automating

REASON FOR AUTOMATED
• Improved product quality: Automation performs the manufacturing
process with greater uniformity and conformity to quality
specifications. Reduction of fraction defect rate is one of the chief
benefits of automation.
• To accomplish processes that cannot be done manually: Certain
operation cannot be accomplished without the aid of a machine.
These processes have requirements for precision, miniaturization or
complexity of geometry that cannot be achieved manually. Example:
manufacturing process based on CAD models and rapid prototyping.
• Increased labor productivity:
 Value of output per person per hour increases-automating a
manufacturing operation usually increases production rate and
labor productivity.
Reason for Automated and Not Automated

• Reduce labor cost:
 Higher investment in automation has become economically
justifiable to replace manual operation. Machines are increasingly
being substituted for human labor to reduce unit product cost.
• To reduce or eliminate routine manual and clerical tasks:
 An argument can be put forth that there is social value in automating
operations that routine, boring, fatiguing and possibly irksome.
Automating such tasks serves a purpose of improving the general
level of working conditions.
• Lower costs: Reduce scrap, lower in-process inventory, superior
quality, shorter lines.
• Reducing manufacturing lead time and reduces work-in-
progress: Respond quickly to the customers’ needs and rapid
response to changes in design.
• Improve worker safety: By automating a given operation and
transferring the worker from activate participation in the process to a
supervisory role, the work is made safer.

• To avoid the high cost of not automating:
• The advantage of automating cannot easily be demonstrated on a
company’s authorized from. The benefits of automation often show
up in unexpected and intangible ways, such as improved quality,
higher sales, better labor relationship and better company image.
• Companies that do not automate are likely to find themselves at a
competitive disadvantage with their customers, their employees
and the general public.
• Competition: Lower prices, better product, better image, better labor
relation.
• New process technologies require automation: Example; Robot
controlled thermal spray torch for coating engine blocks.
• Potential for mass customization and reduced inventory.
• High cost of raw materials

Reason for not automated
• Labor resistance
• Cost of upgraded labor :
Example : Chrysler Detroit plant spend 1 million hours of
retraining
• Initial investment
• Management of process improvement
• Intellectual assets versus technological assets
• Appropriate use of technology
• A system approach to automation is important
• Equipment incompatibilities

Automation Principles and Strategies
1. The USA Principle
2. Ten Strategies for Automation and Process
Improvement
3. Automation Migration Strategy

U.S.A Principle
1. Understand the existing process:
 Input/output analysis: What are the inputs? What are the outputs? What
exactly happens to the work unit between input and output? What is the
function of the process?
 Value chain analysis: How does it add value to the product? What are the
upstream and downstream operations in the production sequence, and can
they be combined with the process under consideration?
 Charting techniques(such as the operation chart and the flow process
chart) and mathematical modeling
2. Simplify the process: Reduce unnecessary steps and moves
3. Automate the process:
 Ten strategies for automation and production systems
 Automation migration strategy

Ten Strategies for Automation and
Process Improvement
If automation seems a feasible solution to improving productivity, quality, or other
measure of performance, then the following ten strategies provide a road map to
search for these improvements
1. Specialization of operations: use of special-purpose equipment
2. Combined operations: performing more than one operation at a given machine,
thereby reducing the number of separate machines needed.
3. Simultaneous operations
4. Integration of operations
5. Increased flexibility
6. Improved material handling and storage
7. On-line inspection
8. Process control and optimization
9. Plant operations control
10. Computer-integrated manufacturing

Automation Migration Strategy
For Introduction of New Products
1. Phase 1 – Manual production
 Single-station manned cells working independently
 Advantages: quick to set up, low-cost tooling
2. Phase 2 – Automated production
 Single-station automated cells operating independently
 As demand grows and automation can be justified
3. Phase 3 – Automated integrated production
 Multi-station system with serial operations and
automated transfer of work units between stations

Automation
Migration
Strategy

Levels of Automation
Cell or system level
Machine level
Device level
Plant level
Enterprise level

1) Device
• The lowest level and it includes the actuators, sensors and other hardware
components that comprise machine level.
• The devices are combined into the individual control loops of the machine.
Example: the feedback control loop for one axis of a CNC machine.
2) Machine
• Hardware at the device level is assembled into individual machines.
Example: CNC machine tools and similar production equipment, industrial
robot and AGV.
• Control function at this level includes performing the sequence of steps in
the program of instructions in correct order and making sure that each step
is properly executed.
3) Cell or system
• Manufacturing cell or system level, this cell operates under instructions
from the plant level. It is a group of machines or workstations connected
and supported by a material handling system, computers, and other
equipment appropriate to the manufacturing process.

4) Plant level
• This is the factory or production systems level. It received
instructions from the corporate information system and translates
them into operational plans for production.
• The functions include: order processing, process planning, inventory
control, purchasing, material requirement planning, shop floor control
and quality control.
5) Enterprise level
• This is the highest level, consisting of the corporate information
system. It concerned with all of the function necessary to manage the
company: marketing and sales, accounting, design, research,
aggregate planning and master production scheduling.
 A manufacturing system is defined in this book as a collection of
integrated equipment designed for some special mission, such as
machining a defined part family or assembling a certain product.
Manufacturing systems include people. The manufacturing systems
in a factory are components of a larger production system,

Fig. 4.6 Production system, which is defined as
the people, equipment, and procedures that
are organized for the combination of
materials and processes that comprise a
company’s manufacturing operations.
Production systems are at level 4, the plant
level, while manufacturing systems are at
level 3 in the automation hierarchy.
Production systems include not only the
groups of machines and workstations in
the factory but also the support procedures
that make them work.
Procedures include process planning,
production control, inventory control &
material requirements planning, shop

Homework
1) A beverages plant plan to mass produce orange flavor drink
for 4 different brands. All 4 brands using the same aluminium
can size but different in printing label on the can. In your
opinion what types of automated manufacturing system is
most suitable to produce 10,000 can/day and each brand is
different in quantity?
2) Identify the situations in which manual labor is preferred over
automation?
3) Review questions: 1.1 to 1.16 & 4.1 to 4.10

Module 1 Lecture 1 Introduction To Automation In Production Systems.ppt

Module 1 Lecture 1 Introduction To Automation In Production Systems.ppt

Recomendados

Más contenido relacionado

Was ist angesagt?

Was ist angesagt?(20)

Similar a Module 1 Lecture 1 Introduction To Automation In Production Systems.ppt

Similar a Module 1 Lecture 1 Introduction To Automation In Production Systems.ppt(20)

Más de Khalil Alhatab

Más de Khalil Alhatab(20)

Último

Último(20)

Module 1 Lecture 1 Introduction To Automation In Production Systems.ppt

Hinweis der Redaktion