This document provides an overview of flexible manufacturing systems (FMS). It defines FMS and discusses their typical components such as machining stations, material handling systems, and load/unload stations. The document outlines the objectives and advantages of FMS, including increased flexibility and responsiveness to changes. It also notes some potential disadvantages like high initial costs and complexity of implementation.

1. IMB 513
MANUFACTURING
SYSTEMS PROJECT
ID NO: 201101574
PROJECT ON
AUTOMATED
PROCESSES-FMS
FLEXIBLE MANUFACTURING
SYSTEMS
Mr Dingalo A Dingalo

2. TABLE OF CONTENTS
Contents
TABLE OF CONTENTS .................................................................................................................... 1
INTRODUCTION ............................................................................................................................ 2
Definition- ................................................................................................................................ 2
AUTOMATED MANUFACTURING CELL ............................................................................................ 3
MANUFACTURING FLEXIBILITY....................................................................................................... 4
EQUIPMENT OF FMS ..................................................................................................................... 5
PRIMARY EQUIPMENT............................................................................................................... 5
SECONDARY EQUIPMENT .......................................................................................................... 6
BASIC COMPONENTS OF A FMS ..................................................................................................... 6
MACHINING STATIONS .............................................................................................................. 7
CNC MACHINING CENTER .......................................................................................................... 7
LOAD/UNLOAD STATIONS ......................................................................................................... 7
MATERIAL HANDLING SYSTEM................................................................................................... 8
OBJETIVES OF FMS........................................................................................................................ 8
TYPES OF FMS-.......................................................................................................................... 9
APPLICATION OF FMS-............................................................................................................... 9
ADVANTAGES OF FMS................................................................................................................. 10
DISADVANTAGES OF FMS ............................................................................................................ 10
REFERENCES ............................................................................................................................... 12

3. INTRODUCTION
A flexible manufacturing system (FMS) is a group of numerically-controlled machine tools,
interconnected by a central control system. The various machining cells are interconnected,
via loading and unloading stations, by an automated transport system. Operational
flexibility is enhanced by the ability to execute all manufacturing tasks on numerous product
designs in small quantities and with faster delivery. It has been described as an automated
job shop and as a miniature automated factory. Simply stated, it is an automated production
system that produces one or more families of parts in a flexible manner. Today, this
prospect of automation and flexibility presents the possibility of producing nonstandard
parts to create a competitive advantage.
Definition-
“A Flexible Manufacturing System (FMS) is a production system consisting of a set of
identical and/or complementary numerically controlled machine which are connected
through an automated transportation system”.
Each process in FMS is controlled by a dedicated computer (FMS cell computer).
The concept of flexible manufacturing systems evolved during the 1960s when robots,
programmable controllers, and computerized numerical controls brought a controlled
environment to the factory floor in the form of numerically-controlled and direct-numerically-
controlled machines.
For the most part, FMS is limited to firms involved in batch production or job shop
environments. Normally, batch producers have two kinds of equipment from which to
choose: dedicated machinery or automated, general-purpose tools. Dedicated machinery
results in cost savings but lacks flexibility. General purpose machines such as lathes, milling
machines, or drill presses are all costly, and may not reach full capacity. Flexible
manufacturing systems provide the batch manufacturer with another option—one that can
make batch manufacturing just as efficient and productive as mass production.
The first FMS was patent in 1965 by Theo Williamson who made numerically controlled
equipment.

4. The word “automated” would distinguish this technology from other manufacturing systems
that are flexible but not automated, such as a manned GT machine cell.
The word “flexible” would distinguish it from other manufacturing systems that are highly
automated but not flexible, such as a conventional transfer line.
AUTOMATED MANUFACTURING CELL
Machine Tool
Machine Work
Robot
Figure 1: automated manufacturing cell
table
Parts Carousel
To qualify as being flexible, a manufacturing system should satisfy several criteria.
Four reasonable TESTS OF FLEXIBILITY:
a) Part variety test. Can the system process different part styles in a non-batch mode?
b) Schedule change test. Can the system readily accept changes in production
schedule: changes in either part mix or production quantities?

5. c) Error recovery test. Can the system recover gracefully from equipment malfunctions
and breakdowns, so that production is not completely disrupted?
d) New part test. Can new part designs be introduced into the existing product mix
with relative ease?
MANUFACTURING FLEXIBILITY
Flexibility
type
Definition Dependent on...
Machine
flexibility
Capability to adapt a given
machine (workstation) in the
system to a wide range of
production operations and part
styles. The greater the range
of operations and part styles,
the greater the machine
flexibility.
 Setup or changeover time.
 Ease of machine reprogramming
(ease with which part programs
can be downloaded to machines).
 Tool storage capacity of
machines.
 Skill and versatility of workers in
the system.
Production
flexibility
The range or universe of part
styles that can be produced on
the system.
 Machine flexibility of individual
stations.
 Range of machine flexibilities of
all stations in the system.
Mix flexibility Ability to change the product
mix while maintaining the
same total production
quantity; that is, producing the
same parts only in different
proportions.
 Similarity of parts in the mix.
 Relative work content times of
parts produced
 Machine Flexibility
Product
flexibility
Ease with which design
changes can be
accommodated. Ease with
which new products can be
introduced.
 How closely the new part design
matches the existing part family.
 Off-line part program
preparation.
 Machine flexibility
Routing
flexibility
Capacity to produce parts
through alternative station
sequences in response to
equipment breakdowns, tool
failures, and other
interruptions at individual
stations.
 Similarity of parts in the mix
 Similarity of workstations
 Duplication of workstations
 Cross-training of manual workers.
 Common tooling.

6. Volume
flexibility
Ability to economically
produce parts in high and low
total quantities of production,
given the fixed investment in
the system.
 Level of manual labor performing
production.
 Amount invested in capital
equipment.
Expansion
flexibility
Ease with which the system
can be expanded to increase
total production quantities.
 Expense of adding workstations.
 Ease with which layout can be
expanded.
 Type of part handling system
used.
 Ease with which properly trained
workers can be added.
EQUIPMENT OF FMS
PRIMARY EQUIPMENT
Work centres
 Universal machining centres (prismatic FMSs)
 Turning centres (rotational FMSs)
 Grinding machines
 Nibbling machines
Process centres
 Wash machines

7.  Coordinate measuring machines
 Robotic work stations
 Manual workstations
SECONDARY EQUIPMENT
Support stations
 Pallet/fixture load/unload stations
 Tool commissioning /setting area
Support equipment
 Robots
 Pallet/fixture/stillage stores
 Pallet buffer stations
 Tools stores
 Raw material stores
 Transport system(AGVs,RGVs,robots)
 Transport units(pallets/stillage’s)
BASIC COMPONENTS OF A FMS
Flexible manufacturing systems consist of hardware and software components. The
hardware components typically comprise of processing stations, material handling systems
and automated material storage and retrieval systems. The processing stations are the
workstations that perform different operations on part families. These workstations are CNC
machine tools, inspection equipment, assembly stations and material loading/ unloading
areas. Material handling systems include automated guided vehicle systems, roller
conveyors, tow line, shuttle cars etc. whereas automated storage and retrieval systems are
used to store and retrieve work parts automatically. Various types of storage and retrieval
systems are pallets, carousels etc. which help in convenient access of different types of
parts from stores and increase machine utilization of flexible manufacturing systems. The
processing and assembly equipment used in a flexible manufacturing system depend upon
the type of work being accomplished by the system. In a system designed for machining
operations, the principal types of processing stations are CNC machines like CNC machining
and turning centers. However, the FMS concept is applicable to various other processes like
automated assembly lines, sheet metal fabrication etc.

8. MACHINING STATIONS
One of the most common applications of flexible manufacturing system is in the machining
operations. The workstations designed in these systems, therefore, predominantly consist
of CNC machines tools. The most common CNC machines tools used include CNC machining
center, in particular, horizontal machining turning centers. These CNC machine tools possess
the features that make them compatible with the FMS. These features include automatic
tool changing and storage, use of palletized work parts, etc.
CNC MACHINING CENTER
A CNC machining center is a highly automated machine tool capable of performing multiple
machining operations under CNC control in one setup with minimal human attention.
Machining centers generally include automated pallet changers to load the work part to the
machine and to unload the finished part that can be readily interfaced with the FMS part
handling system. A CNC machining center is a sophisticated CNC machine that can perform
milling, drilling, tapping, and boring operations at the same location wi th a variety of tools.
LOAD/UNLOAD STATIONS
Load/unload station is the physical interface between an FMS and the rest of the factory. It
is the place where raw work parts enter the system and finished parts exit the system
.Loading and unloading can be accomplished either manually (the most common method) or
by automatic handling systems. The load/unload stations should be ergonomically designed
to permit convenient and safe movement of work parts. Mechanized cranes and other
handling devices are installed to assist the operator with the parts that are too heavy to lift
by hand. A certain level of cleanliness must be maintained at the workplace, and air houses
and other washing facilities are often used to flush away chips and ensure clean mounting
and locating points. The station is often raised slightly above the floor level using as open-grid
platform to permit chips and cutting fluid to drop through the openings for subsequent
recycling or disposal.
The load/unload station includes a data entry unit and a monitor for communication
between the operator and the computer system. Through this system, the operator receives
the instructions regarding which part to load on the next pallet in order to adhere to
production schedule. When different pallets are required for different parts, the correct
pallet must be supplied to the station. When modular fixing is used, the correct fixture must
be specified and the required components and tools must be available at the workstation to
build it. When the part loading procedure is completed, the handling system must launch
the pallet into the system, but not until then; the handling system must be prevented from
moving the pallet while the operator is still working. All of these conditions require
communication between the computer system and the operator at the load/unload station.

9. MATERIAL HANDLING SYSTEM
There are two types of material handling systems which are:
 Primary handling system establishes the basic layout of the FMS and is responsible
for moving work parts between stations in the system
 Secondary handling system consists of transfer devices, automatic pallet changing,
and similar mechanisms located at the workstations
Functions of the Handling System
 Random, independent movement of work pieces between stations.
 Handle a variety of work piece configurations.
 Temporary storage.
 Convenient access for loading and unloading work pieces.
 Compatible with computer control.
The material-handling equipment used in flexible manufacturing systems include robots,
conveyers, automated guided vehicle systems, monorails and other rail guided vehicles, and
other specially designed vehicles. There important features are that they are integrated with
the machine centres and the storage and retrieval systems .For prismatic part material
handling systems are accompanied with modular pallet fixtures .For rotational parts
industrial robots are used to load/unload the turning machine and to move parts between
stations.
OBJETIVES OF FMS
Stated formally, the general objectives of an FMS are to approach the efficiencies and
economies of scale normally associated with mass production, and to maintain the flexibility
required for small- and medium-lot-size production of a variety of parts.
Two kinds of manufacturing systems fall within the FMS spectrum. These are assembly
systems, which assemble components into final products and forming systems, which
actually form components or final products. A generic FMS is said to consist of the following
components:
1. A set of work stations containing machine tools that do not require significant set-up
time or change-over between successive jobs. Typically, these machines perform
milling, boring, drilling, tapping, reaming, turning, and grooving operations.
2. A material-handling system that is automated and flexible in that it permits jobs to
move between any pair of machines so that any job routing can be followed.

10. 3. A network of supervisory computers and microprocessors that perform some or all
of the following tasks: (a) directs the routing of jobs through the system; (b) tracks
the status of all jobs in progress so it is known where each job is to go next; (c)
passes the instructions for the processing of each operation to each station and
ensures that the right tools are available for the job; and (d) provides essential
monitoring of the correct performance of operations and signals problems requiring
attention.
4. Storage, locally at the work stations, and/or centrally at the system level.
The jobs to be processed by the system. In operating an FMS, the worker enters the job to
be run at the supervisory computer, which then downloads the part programs to the cell
control or NC controller.
TYPES OF FMS-
 Sequential FMS
 Random FMS
 Dedicated FMS
 Engineered FMS
 Modular FMS
APPLICATION OF FMS-
 Metal-cutting machining
 Metal forming
 Assembly
 Joining-welding (arc , spot), gluing
 Surface treatment
 Inspection
 Testing

11. ADVANTAGES OF FMS
The potential benefits from the implementation and utilization of a flexible manufacturing
system have been detailed by numerous researchers on the subject. A review of the
literature reveals many tangible and intangible benefits that FMS users extol. Thes e benefits
include:
 achieving a highly automated manufacturing process with rigorous computerized
monitoring and management of quality and productivity
 making manufacturing operations readily scalable for different levels of output
 allowing customization and reconfiguration of manufacturing processes with
minimal downtime and cost
 providing management with detailed and timely information about the
manufacturing process
 enabling manufacturers to coordinate their work processes with those of their
suppliers and customers to maximize efficiency and minimize costs
 Increased machine utilization
 Fewer machines required
 Reduction in factory floor space required
 Greater responsiveness to change.
 Reduced inventory requirements
 Lower manufacturing lead times
 Reduced direct labor requirements and higher labor productivity
 Opportunity for unattended production
DISADVANTAGES OF FMS
Despite these benefits, FMS does have certain limitations. In particular, this type of system
can only handle a relatively-narrow range of part varieties, so it must be used for similar
parts (family of parts) that require similar processing. Due to increased complexity and cost,
an FMS also requires a longer planning and development period than traditional
manufacturing equipment.
Equipment utilization for the FMS sometimes is not as high as one would expect. Japanese
firms tend to have a much higher equipment utilization rate than U.S. manufacturers
utilizing FMS. This is probably a result of U.S. users' attempt to utilize FMS for high-volume
production of a few parts rather than for a high-variety production of many parts at a low
cost per unit. U.S. firms average ten types of parts per machine, compared to ninety-three
types of parts per machine in Japan.

12. Other problems can result from a lack of technical literacy, management incompetence, and
poor implementation of the FMS process. If the firm misidentifies its objectives and
manufacturing mission, and does not maintain a manufacturing strategy that is consistent
with the firm's overall strategy, problems are inevitable. It is crucial that a firm's technology
acquisition decisions be consistent with its manufacturing strategy.
If a firm chooses to compete on the basis of flexibility rather than cost or quality, it may be a
candidate for flexible manufacturing, especially if it is suited for low- to mid-volume
production. This is particularly true if the firm is in an industry where products change
rapidly, and the ability to introduce new products may be more important than minimizing
cost. In this scenario, scale is no longer the main concern and size is no longer a barrier to
entry.
However, an FMS may not be appropriate for some firms. Since new technology is costly
and requires several years to install and become productive, it requires a supportive
infrastructure and the allocation of scarce resources for implementation. Frankly, many
firms do not possess the necessary resources. Economically justifying an FMS can be a
difficult task—especially since cost accounting tends to be designed for mass production of
a mature product, with known characteristics, and a stable technology. Therefore, it is
difficult to give an accurate indication of whether flexible manufacturing is justified. The
question remains of how to quantify the benefits of flexibility. In addition, rapidly-changing
technology and shortened product life cycles can cause capital equipment to quickly
become obsolete.
For other firms, their products may not require processes at the technological level of an
FMS. IBM found that a redesigned printer was simple enough for high-quality manual
assembly and that the manual assembly could be achieved at a lower cost than automated
assembly. Potential FMS users should also consider that some of the costs traditionally
incurred in manufacturing may actually be higher in a flexible automated system than in
conventional manufacturing.

13. REFERENCES
1) J. A. Buzacott,'The Fundamental Principles of Flexibility in Manufacturing Systems',
Proceedings of the 1st International Conference on Flexible Manufacturing Systems.
2) ASKIN R. G., and STANDRIDGE C. R., 1993 “Modelling and Analysis of Manufacturing Syste ms”.
John Wiley and Sons, Inc.
3) Mikell P. Groover, Automation, Production Systems, and Computer-Aided Manufacturing.
Prentice-Hall, Englewood Cliffs NJ (1980).
4) Tauseef Aized (2010). Flexible Manufacturing System: Hardware Requirements, Future
Manufacturing Systems, Tauseef Aized (Ed.), ISBN: 978-953-307-128-2,
5)http://www.intechopen.com/books/future-manufacturing-systems/flexible-manufacturing-system-
hardwarerequirements