cim notes.pdf

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Computer integrated

manufacturing

(Lecture #13)

CIM (Computer Integrated CIM (Computer Integrated Manufacturing)Manufacturing)

=Historical background=What is CIM?=Definition of CIM=Implementation and operation of CIM=Hierarchical and Distributed Control= (Virtual) Enterprises & ERP Systems=Data mining=Lean Production & Agile Manufacturing=Flexible Manufacturing System=Flexible Manufacturing Cell=Concurrent engineering=Design for ‘X’=Reverse engineering

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Computer Integrated Computer Integrated ManufacturingManufacturing

CIM allows the online and batch-related acquisition of process and quality data.

The flow of material within a multi-stage production process can be planned at any time and monitored from the central station.

Computer Integrated Computer Integrated ManufacturingManufacturing

Job and materials management permits job-controlled production.

Even if complaints are received years after delivery of the components produced, both production and quality data and the materials used can be easily determined.

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CIM ConceptCIM Concept

l Acquisition of possible quality-relevant data of different process steps

l Serial interfacing of SPCs of a wide variety of manufacturers

l Assignment of data of each process step to individual silicon wafers (materials tracking)

l Acquisition of the wafer qualityl Visualisation of the possible quality-relevant data

on the wafer qualityl Evaluation of the datal Data storage for long-time CAQl Job and materials management

Historical Background (I)Historical Background (I)

1970s - 1980s…Flexible Manufacturing Systems/Cells

•“… a group of CNC machinery/equipment linked by an automated materials handling system, whose operation is integrated by supervisory computer control …”

•Provided efficient mid-volume, mid-variety production

•Increased machine utilization•Reduced work-in-process inventory, labor and

tooling costs, setup costs, lead time, lot size•Ability to react quickly to engineering changes

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Historical Background (I)Historical Background (I)

1980s...Computer Integrated Manufacturing

•“… computer assisted control and integration at all levels of a manufacturing enterprise …”

•Strict hierarchical information flow

•Totally automated, unmanned, paperless factory

•Integration problems in heterogeneousm environments

Historical Background (I)

1990s…Intelligent Manufacturing•“… architecture for highly decentralized

manufacturing systems, built from a modular mix of autonomous, cooperative, and intelligent elements (agents) …”

•Re-emergence of the human factor seeking to maximize the use of human intellectual skills and flexibility

•Migrating from hierarchy to Vertically•Capability of rapid self-reconfiguration by

incorporating human and machine intelligence

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Historical Background (I)

1990s…Extended Enterprises• “… global integration throughout the complete

supply chain in manufacturing: Virtual Enterprise …a community of factories each focused on what it does best, all linked by a network that would enable them to operate as one flexibly and inexpensively regardless of their location”

l An enterprise mostly made of functions provided by other enterprises

l Extensive use of standards and information technology tool

l Organizations and teams operate autonomously but cooperatively

l Pushing toward true integration of design and manufacturing

What is CIM?What is CIM?

l a computer system?l a management philosophy?l a competitive strategy?l a data management and networking

problem?l a concept?l a technology?l a method for eliminating direct labor?l a deterministic technical system?l a socio-technical system?

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What is CIMWhat is CIM??

technology, tool or method used to improve entirely the design and manufacturing process and increase productivity

What is CIMWhat is CIM??l using computers to help people and machines to

communicate series of integrated activities and operations involving – the design, – materials selection, – planning, – production, – quality assurance, – management – marketing of discrete consumer and durable goods

l deliberate integration of automated systems logical organization of individual engineering, production and marketing/support functions into a computer integrated system

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l focuses on the computer as the center of control of the entire factory, starting from the computerization of the fabrication and assembly processes to the information flow for

– production control,

– quality,

– maintenance,

– material handling,


l involves the use of computers to assist in

– the design,

– handling,

– processing,

– cataloging of materials as they flow through the manufacturing processes

l not computer controlled, but is the use of the computer assets to assist in difficult areas of manufacturing

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What is CIM?What is CIM?l use of electronic technology to

streamline traditionally separate phases,

– including concept,

– design,

– manufacture,

– analysis,

– maintenance,

into a single process in order to reduce lead time and improve quality of the product


l an approach to the organization and management of a firm, in which the functions of – design, – manufacturing, – production management are mutually

rationalized – completely coordinated, through the

use of appropriate levels of computer and information/communication technologies

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l use of computer hardware, software, and communications networks in all aspects of a manufacturing company including inventory control, quality control, planning, cost accounting, design, and manufacturing (machine control)


l utilizes the computer, not only to automate the design, control, assembly, and planning, but to link these processes into an organizational entity

l control of information flow and material or product flow to best serve the customer

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l including information, to best serve the customer; typically incorporating together the following technologies:

computer aided manufacturing,

computer aided design,

computer aided process planning,

computer aided quality control,

computer aided design


l concept of a completely automated factory in which all the functions of a company (design methods, production, administration, accounting, marketing, etc.) are integrated and controlled in the company and use common data shared through the same database

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l consists of three dimensions:

l the engineering dimension involves CAD/CAM and CAPP activities;

l the networking and systems dimension;

l the continuous improvement dimension that encompasses areas such as MRP II, TQM, JIT and theory of constraints (TOC)

Computer Integrated Manufacturingis the integration of the total

manufacturing enterprise through the use of integrated systems and data communications coupled with new managerial philosophies that improve organizational and personnel efficiency.

Definition of CIMDefinition of CIM

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Definition of CIMDefinition of CIM

DesignManufac-turing

Business

CIM

Major Subsystems in CIM

Marketing

CA- Storage &

Transportation(Logictics)

Information

System Quality

Product

CAD

Tool Machine

CAPP

PPS (MRP)

CAM

SFC CAPC TMS QC

Lower Level Controllers

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CIM Representative TopicsCIM Representative Topics

l Computer-aided concurrent engineering (CACE); Design for Manufacturability (DFM)

l PDES/STEP-based manufacturing applications l Computer numerical control (CNC); Direct/distributed

numerical control (DNC)l Computer process control, including adaptive process

controll Rapid prototyping principles & research

opportunitiesl Programmable controller/microcomputer applicationsl Computer aided process planning (CAPP), including expert

system applications l Industrial robot applications, including off-line

programmingl Group technology (GT) & GT manufacturing cells

CIM Representative TopicsCIM Representative Topics

l Flexible manufacturing systems (FMS's)l Local area networks, including MAP/TOP network

standards & ISO reference model l Production planning & control, including JIT andSAPl Product/process simulationl Automated material handlingl Data entry systemsl Automated inspection systems & quality engineeringl Productivity engineering, including manufacturing cost

analysisl MRP vs. JIT production systems; JIT vs. lean

manufacturing l AI applications in CIM l Other topics: Automation & human labor; green

manufacturing; AHP (decsion support tools)

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FLEXIBLE

MAUFACTURING

SYSTEM (FMS)

Conceptual idea is attributed to David Williamson in the 1960’s, but it took development of CNC and programmable controllers to make the concept truly viable.

Flexible ManufacturingFlexible Manufacturing SystemSystem

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A series of automatic machine tools or items of fabrication equipment linked together with an automatic material handling provision for random fabrication of parts or assemblies that fall within predetermined families


FMS is a group of NC machine tools that can

randomly process group of parts, having

automated material handling and central

computer control to dynamically balance

resource utilization so that the system can

adapt automatically to changes in parts

production mixes, and levels of output.

(Kearney and Treaker)


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A manufacturing system is a collection of integrated equipment and human resources, whose function is toperform one or more processing and/or assembly operations on a starting raw material, part, or set of parts.

Manufacturing System

=What are they?=How are they combined?=How are they organized?=Production machines=Material handling system=Computer control system=Human resources

Manufacturing System Components

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=Types of operations=Number of workstations & layout=Level of automation=Part or product variety (how to handle; types of flexibility)

Classification of Manufacturing System

=Mass production (transfer line)=Special systems=Flexible manufacturing system (FMS)=Flexible manufacturing cell (FMC)=Stand-alone CNC systems

Types of Manufacturing System

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FMS is a system dealing with ü high level distribution,ü data processingü and automated material flowUsing

computer controlled machines, assembly cells, industrial robots, inspection machines altogether with computer integrated material handling and storage systems.

( Mehdi Kaighobad)


vFMS is a collection of

production equipment

logically organized under a host computer

and physically connected by a central transport system.

(David Perish)


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FMS is a system consisting of 3 subsystems;fabricationmachiningassembly.

These subsystems are integrated with automatic storage; computer aided design, material handling devices and a computer.

(Kusiak)


FMS is Business Driven=Improved profitability=Reduced lead times=Reduced inventory levels=Rapid response to market changes=Lower staffing levels=Improved manufacturing effectiveness=Increased operational flexibility=Increased predictability=Increased control


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FMS: Impact on Manufacturing=Need for managing change=More complex products=Need for greater flexibility=Need for faster time-to-market


Definition: FMSGroup of machines or processes, integrated with material handling equipment, and under the direction of a (central) control system, to produce avariety of parts, at non-uniform production rates, batch sizes & quantities.


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Operating Flexibility

Part

Desi

gn F

lexib

ilit

y

Types of FMS FlexibilityProduct design —Makes it possible toaccommodate a variety of product designs,including new products and modified designs; stems from recent advances in manufacturing controls that allow design details to reside in a machine software rather than the mechanics of its physical structure.


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Types of FMS FlexibilityOperating — Makes it possible to reducemanufacturing costs while responding to changes in manufacturing conditions, such as production schedules and model mix; characterized by capability to make up lost production (achieved in past through large WIP inventory)


=Microprocessor=Digital system simulation=Design optimization tools=Computer aided process planning=Process controlled quality=More software control=Advanced industrial controls=Industrial robots

FMS: Important Technologies

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=Advanced sensors=Improved diagnosis=Higher speed=On-line/in-process inspection=Quick-change tooling=Tool wear monitor=Development with other processes,

e.g., forming; heat treat; assembly

FMS: Other SignificantTechnologies

=Type of equipment available vs. operations needed=Types of parts & number of part #'s=Part tolerances & material requirements=Design change expected=Operational/schedule change expected

Invest or Not Invest??

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=Production volumes=Product life & lead time requirements=Direct labor available=Dollars available to invest=Other investment alternatives for company



Product Flexibility (no. of part nos.Pro

ducti

on v

olu

me (

part

s/year)

Computer Integrated

Manufacturing Systems

(CIMS)CNC

Tra

nsf

er

line

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System Trade-offs

l Transfer lines

l Large volume production/high output rate (~15,000+ parts/yr)

l Parts are virtually identical; sometimes only one part

l Changeover difficult/requires shutdown of line & machine retooling

l Need to replace machines for major design changes

System Trade-offsl Stand-alone CNC

l Efficiently accommodates part design change

l Reprogram for design changeover/design change

l Low production quantities (~up to 800 parts/yr)

l CIMS

l Between high production rates & high flexibility (mid-volume)

l Fills in gap between transfer lines & low volume

l CNC machines

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FMS ConceptsFMS Concepts

l Single station routing part flow

l Sequential routing part flow

l Random routing part flow


l Single station

l Tailor to design or operational change need

l Attributes of both random & sequential flow

l Problem areas: overall accuracy & required head investment

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l Sequential flow

l Accommodates operational part mix change; higher throughput capacity

l Similar operation sequences

l Simpler material handling

l Potential problems: over & under utilization; machines repeated for repeated operations


l Random flow

l High degree of design flexibility & limited operating flexibility

l Complex material handling system

l Potential problems: availability of machine tools; reduced capacity with over & under utilized machine tools

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FMS: Machine Tool TradeFMS: Machine Tool Trade--offsoffs

Tooling Flexibility Prod. Rate

Head changer

Multiple tool Moderate Moderate

Head indexer

Multiple tool Lowest Highest

Machining center

Single point (spindle)

Highest Lowest

Computer Functions for FMS

=Control of each workstation=Distribution of control instructions to workstations=Production control=Traffic control=Shuttle control=Workhandling system monitoring=Tool control=System performance monitoring & reporting

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Personnel Requirementsfor FMS

=System manager=Electrical technician=Mechanical/hydraulic technician=Tool setter=Fixture setup & lead man=Load/unload man=Rover operator=Other: NC programmer; computer programmers;

other support staff

Manufacturing CellsManufacturing Cells

l Single station manned cells

l Single station automated cells

l Applications of single station cells

l Analysis of single station cells

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Single Station Manned CellsSingle Station Manned Cells

l Requires shortest amount of time to implement

l Requires least capital investment

l Technologically, easiest to install & operate

l Often results in lowest cost per unit produced

l Most flexible manufacturing system

Single Station Automated CellsSingle Station Automated Cells

l Reduced labor requirement/cost

l Easiest & least expensive among automated systems to implement

l Higher production rates possible

l First step in implementing integrated multistation automated system

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Applications of Single Station Applications of Single Station CellsCells

l CNC machining center with parts carousel & automatic pallet changer

l CNC turning center with parts storage tray & robot (same or different parts)

l Cluster of CNC turning centers, each producing different part

l Plastic injection molding machine with mechanical arm to remove part

l Automated electronic assembly machinel Robotic assembly celll Stamping press that punches & forms small sheet

metal parts

Analysis of Single Station CellsAnalysis of Single Station Cells

l Determine number of required workstations

l Include setup timel Consider availability & machine

utilizationl Consider worker efficiencyl Consider defect ratel Determine number of machines for

single worker (cluster of machines)

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WHY NAME IT

FLEXIBLE MANUFACTURINGSYSTEM (FMS) ??

The Eleven Flexibilities

1 Machine Flexibility: wide range of operations, minor set ups, generic fixtures, large tool magazines, automatic tool changers

2 Material Handling Flexibility: move various parts between machines and storage areas and, maintain proper oritentation

3 Operation Flexibility: ability to use different processing operations to produce part features

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4 Routing Flexibility: ability to use different machines to produce parts under the same set up to ensure against breakdowns and bottlenecks

5 Product Flexibility: ease of changing over the system to produce a new set of parts

6 Volume Flexibility: insensitivity of profit to production volume

7 Expansion Flexibility: ease of adding additional capacity

8 Control Flexibility : ability to run unattended for a long period

9 Production Flexibility : range of part types that could be produced without major capital expense Insensitivity of profit to production volume

10 Process Flexibity : Ability to Produce variety of Parts with the same set up time

11 Market Flexibility : sum of product, Process and Volume Expansion

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A general view of a flexible manufacturing system, showing several machine tools and an automated guided vehicle (Cincinnate Milacron Inc.)

Why FMSWhy FMS

Job Shops constitute 70% of the industrial systems

Its cheap

Its flexible

Its diverse

But highly inefficient production system

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Why FMSWhy FMS

=Increased Productivity=Cost-effective Investment=Flexibility

High Quality

Lower Cost

Shorter Lead Time

Resond to Change

Transfer Line

SpecialSystem

Flexible Manufacturing

Systems(FMS)

Manufacturing Cell

Standard and General Purpose

Machine

Low Product Variety High

High

Low


Pro

ducti

on v

olu

me

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A flexible manufacturing cell is a set of numerically controlled machines linked by a flexible material handling system ( e.g., robot, automated guided vehicle AGV) all controlled by a computer system.

Flexible Manufacturing Cell


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Automated Storage and Retrieval Systems

AGV

AGV Machine

Center 2

M/CCELL

Load area/unload

Machine Center 3

CELLCONTROLLER


Machines

· Backbone of system

· used for producing prismatic shapes

(including engine blocks, pumps casting having

no shapes as well as rotational parts)

· robots grip rotational parts

· fixtures grip prismatic parts

· tool changers /tool magazines to minimize

setup times

System Components

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Part Movement SystemØ ConveyorsØ tow cartsØ rail cartsØ AGVs

Parts are transported on palletized fixturesbetween stations

Docking areas are used for in process storage

Shuttles receive the loaded part and store indocks

Supporting Workstations

Provision of load/unload station

Automatic washers for parts cleaning

Centralized storage area containing pallets

Coordinate measuring machines (CMM)

for accurate measurements and locations

of features

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System Controller

= Brain of the cell

= It is a computer with an attendant

worker to keep track of performance

and intervene to change priorities

= Keeps track of system status

= The status includes location of all parts,

tools, carts including those in waiting

Watches operational status of each machine

Controller downloads commands to individual

machines and system components

In more advanced systems, the controller is

intelligent and thinks ahead

System Controller

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Sends AGVs to pick parts in advance

The controller makes sure the parts are

automatically routed to alternate

machines in case of machine breakdowns

System Controller

· Either the controller or the CNC machine

itself can keep track of cutting time for

each tool and know when it is time to

change the tool to prevent quality

problem

· Travel times of AGVs are monitored to

change the batteries

· Controller software development is the most

complex task

System Controller

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FMS DESIGN

Strategic issuesTactical issues

Why FMS be installed ?Strategic Issues

Message to customers as well as competitors

progressiveness

high tech processes

responsiveness

rapidness

meet customized market demand quickly

eagerness for embracing engineering changes

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Tactical issues

Select type of parts to be made on FMS

Decide operation sequence to be used for making these parts

Select experienced vendors and have consultations with them on FMS desirable features and costs

Hardware Decisions

It includes machining centers, tool changers, pallet loaders, cutting tools, pallets, fixtures, system storage, machine buffers, material handling carts and system controllers

Auxiliary components

tool wear sensors, on line inspection devices, data acquisition devices

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Computer Integrated ManufacturingComputer Integrated Manufacturing

Questions :1. Define computer integrated

manufacturing (CIM).2. What role does the computer (or

computer technologies) play in CIM?2. How is CIM different from

“conventional” manufacturing concepts?3. What is meant by the term concurrent

engineering?4. What is distributed control ?5. Why is distributed control easier to

maintain than a centralized computer planning and control system?

cim notes.pdf

Documents

flexible manufacturing systemfms

flexible manufacturing systemtypes

single station cellsl

flexible manufacturing cell

flexible manufacturing system

cim representative topicsl

computer integrated manufacturing

computer aided design