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5/22/2018 Mikell P. Groover

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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. 1/29

Part VI MANUFACTURING

SUPPORT SYSTEMS

Chapters:

23. Product Design and CAD/CAM in the Production System

24. Process Planning and Concurrent Engineering

25. Production Planning and Control Systems

26. Just-In-Time and Lean Production



Manufacturing Support Systems

in the Production System


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Ch 23 Product Design and CAD/CAM

in the Production System

Sections:

1. Product Design and CAD

2. CAD System Hardware

3. CAM, CAD/CAM, and CIM

4. Quality Function Deployment



Manufacturing Support Systems

The procedures and systems used by a firm to manage its

production operations and solve the technical and logistics

problems associated with:

Designing the products, Planning the processes,

Ordering materials,

Controlling work-in-process as it moves through the

plant, and

Delivering quality products to customers


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The Design Process

The general process of design is characterized as an

iterative process consisting of six phases:

1. Recognition of need - someone recognizes the need that

can be satisfied by a new design

2. Problem definition - specification of the item

3. Synthesis - creation and conceptualization

4. Analysis and optimization - the concept is analyzed and

redesigned

5. Evaluation - compare design against original specification

6. Presentation - documenting the design (e.g., drawings)



The Design Process


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Computer-Aided Design (CAD)

Any design activity that involves the effective use of the

computer to create, modify, analyze, or document an

engineering design

Commonly associated with the use of an interactive

computer graphics system, referred to as a CAD system

The term CAD/CAM is also used if the computer system

supports manufacturing applications as well as design

applications



Reasons for Using a CAD System

To increase the productivity of the designer

To expand the available geometric forms in design - wider

range of mathematically defined shapes possible

To improve the quality of the design - more engineeringanalysis possible, consideration of more alternatives

To improve design documentation - better drawings than

with manual drafting

To create a manufacturing database - creation of the

design documentation also creates manufacturing data

To promote design standardization - use of design rules to

limit the number of hole sizes, fasteners, etc.


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The Design Process

Using CAD


Automation, Production Systems, and Computer-Integrated Manufacturing, Third Edition, by Mikell P. Groover. 10/29

How a CAD System is Used

in Product Design (Steps 3 - 6)

3. Geometric modeling

CAD system develops a mathematical description ofthe geometry of an object, called a geometric model

4. Engineering analysis

Mass properties, interference checking forassemblies, finite element modeling, kinematicanalysis for mechanisms

5. Design evaluation and review

Automatic dimensioning, error checking, animation

6. Automated drafting

Preparation of engineering drawings quickly


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Geometric Models in CAD

Wire-frame model

Solid model



CAD System Hardware

The hardware for a typical CAD system consists of the

following components:

1. One of more design workstations

2. Digital computer3. Plotters, printers, and other output devices

4. Storage devices


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Typical CAD System Configuration



Design Workstations

The interface between the computer and the user in the

CAD system

Functions:

1. Communicate with the CPU2. Continuously generate a graphical image

3. Provide digital descriptions of the image

4. Translate user commands into operating functions

5. Facilitate interaction between the user and the system


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CAD System Configurations

1. Host and terminal

Mainframe serves as host for graphics terminals

The original configuration in the 1970s and 1980s

when CAD technology was first developing

2. Engineering workstation

Stand-alone computer system dedicated to one user

Often networked for sharing data and plotters

3. CAD system based on a personal computer PC with high-performance CPU and high resolution

graphics display monitor



Host and Terminal Configuration

Original CAD system configuration in 1970s and 1980s

Host computer is a mainframe or large mini computer


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Engineering Workstation Configuration

An engineering workstation is a stand-alone computer

system dedicated to one user and capable of executinggraphics software and other programs requiring high-

speed computational power



CAD System based on a PC

This is a personal computer with a high-performance CPU

and high resolution graphics display screen

PC-based CAD systems can be networked (as shown) to

share files, output devices, and for other purposes


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Computer-Aided Manufacturing

The effective use of computer technology in

manufacturing planning and control

Most closely associated with functions in manufacturing

engineering, such as process planning and NC part

programming

CAM applications can be divided into two broad

categories:

1. Manufacturing planning

2. Manufacturing control



CAM Applications in

Manufacturing Planning

Computer-aided process planning (CAPP)

Computer-assisted NC part programming

CAD/CAM assisted NC part programming

Computerized machinability data systems

Computerized work standards

Cost estimating

Production and inventory planning

Computer-aided assembly line balancing


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CAM Applications in

Manufacturing Control

Process monitoring and control

Quality control

Shop floor control

Inventory control

Just-in-time production systems



CAD/CAM

Concerned with the engineering functions in both design

and manufacturing

Denotes an integration of design and manufacturing

activities by means of computer systems Goal is to not only automate certain phases of design

and certain phases of manufacturing, but to also

automate the transition from design to manufacturing

In the ideal CAD/CAM system, the product design

specification residing in the CAD data base would be

automatically converted into the process plan for

making the product


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Computer Integrated Manufacturing

Includes all of the engineering functions of CAD/CAM

Also includes the firm's business functions that are related

to manufacturing

Ideal CIM system applies computer and communications

technology to all of the operational functions and

information processing functions in manufacturing

From order receipt,

Through design and production,

To product shipment



The Scope of CAD/CAM and CIM


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Computerized Elements

of a CIM System



Quality Function Deployment

A systematic procedure for defining customer desires and

requirements and interpreting them in terms of product

features and process characteristics

A series of interconnected matrices are establishedbetween customer requirements and the technical

features of a proposed new product

The matrices are a progression of phases in which

customer requirements are first translated into product

features, then into manufacturing requirements, and

finally into quality procedures for controlling the

manufacturing operations


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Quality Function Deployment

Shown as a series of matrices that relate customer

requirements to successive technical requirements in atypical progression



The Starting Matrix:

The House of Quality


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Steps in QFD: The House of Quality

1. Identify customer requirements

2. Identify product features needed to meet customer

requirements

3. Determine technical correlations among product features

4. Develop relationship matrix between customer

requirements and product features

5. Comparative evaluation of input customer requirements

6. Comparative evaluation of output technical requirements

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