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1999 Systems Engineering Capstone Conference • University of Virginia
DEVELOPMENT OF AN INTEGRATED MANUFACTURING WORK INSTRUCTION
SYSTEM
Student Team: William E. Hancock IV, Jon J. Handel, Brandon K. Lucado, Sara E. Matys
Faculty Advisor: Christina Mastrangelo, Department of Systems Engineering
Client Advisors: Mark Tran and Neil Currie
The Boeing Company
Process Assembly Manufacturing Business Unit
Seattle, WA
E-mail [email protected]
KEYWORDS: Work Instructions, Data Model,
Manufacturing Engineer, Aileron, User Interface
ABSTRACT
In order to improve their manufacturing work
instructions, Boeing enlisted the help of a Capstone
Team at the University of Virginia to develop an
integrated prototype work instruction system. After
detailed analysis, the Capstone group determined that a
custom developed product would be better suited to
meet the needs of the Process Assembly MBU. This
prototype was developed through PowerSite, for the
user interface, and SQL Anywhere as the database. The
prototype development included the following steps:
analysis of the current work instructions, database
design, and development of the user interfaces for the
manufacturing engineer and the factory mechanic. The
developed prototype proves the effectiveness of an
integrated work instruction system, but the Capstone
team recommends that the Process Assembly MBU
either use alternative development products, or wait for
a more suitable off-the-shelf product.
documents with graphics, audio, and video into a userfriendly single source of information. Boeing enlisted
the help of a Capstone Team at the University of
Virginia to develop an electronic integrated prototype
work instruction system.
OBJECTIVES
The primary objective of the capstone project is to
develop a prototype work instruction delivery system
for the aileron – a composite part manufactured in the
Process Assembly Manufacturing Business Unit. There
are several additional project goals:





To create a system that integrates a graphical
representation of the build process
To create an easily updateable system
To create a system that is easy to understand and
use for both the manufacturing engineer and the
factory mechanic
To decrease reference retrieval time for factory
workers
To increase efficiency and decrease rejected parts
in the Process Assembly MBU
To cut the overall cost of making a part
INTRODUCTION

Manufacturing companies regularly look for ways to
increase efficiency in their factories. One approach is
to improve their manufacturing work instructions.
Work instructions that are text based, difficult to
understand, and not easily accessible tend to slow
workers and factories down. Even in today’s modern
manufacturing environments, paper-based work
instructions and other documents tend to be the norm.
However, there are many documented success stories of
companies that have switched to electronic work
instruction systems that integrate multiple text
These goals provide the basis for an analysis of the
options available to Boeing for a prototype work
instruction system, and the next section describes how
these goals serve as the basis for our analyses.
TWO-TIERED ANALYSIS
The analysis of alternatives was performed in two
tiers. The first tier involves analyzing existing products
and a University of Virginia developed system. In the
second tier, various combinations of software are
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Development Of An Integrated Manufacturing Work Instruction System
analyzed in order to determine which software products
the team should use to develop the work instruction
system.
Criteria for evaluating and comparing alternatives were
developed and prioritized through discussions with our
client. In this phase, the following measures of
performance (MOPs) were used to analyze four
commercially available software solutions and a
prototype developed by the capstone team:
1. Ease of Use for Mechanics
2. Configuration Control (tied for first in order of
importance)
3. Information Retrieval Time
4. Cost
5. Creation Time*
6. Ease of Integration*
7. System Development Time*
Note: * means MOPs are all of approximately the same
importance
As a result of this analysis, the preferred alternative
is a prototype developed by the UVA team that is
tailored to meet the specific needs of Boeing. The cost
criteria influences this outcome because the commercial
packages are very expensive and partly duplicate
systems already in place at Boeing.
The second phase of the analysis identified
implementation alternatives for the prototype. The team
developed a list of measures with which they could
determine the best software products to use in the
development of a prototype. These measures take into
account the factors that the team felt are the most
important in delivering a prototype that will provide all
of the necessary capabilities. The following list
represents a full list of MOPs in order of importance to
the completion of the project.
1.
2.
3.
4.
5.
6.
Learning Curve for the team
Future Scalability (expanding the database to
include all parts in the Process Assembly MBU)*
Technical Support (at Boeing) *
Cost (for students)
Cost (of implementation)**
World Wide Web Capability**
Note: MOP 2&3 and 5&6 are of approximately the
same importance.
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The result of the second analysis was to use the
Sybase product PowerSite to develop the user interface
for the World Wide Web. In addition, it determined
that prototype should use an Oracle database.
The steps taken to develop the prototype began with
a thorough analysis of the current work instructions.
Next, the design of the database was designed, and
finally, the user interfaces for the manufacturing
engineer and the factory mechanic were designed and
implemented.
ANALYSIS OF WORK INSTRUCTIONS
Analyzing the current work instructions was
necessary in order to determine the best way to develop
new work instructions. The main procedures for
analyzing the documents were reading, questioning, and
comparing. Reading the documents provided the team
with knowledge of how the instructions are laid out,
how they are worded, and how they refer to other
documents. The team also looked at documents cited in
the work instructions to determine what exactly the
instructions were referencing. The most important tool
used to analyze the current work instructions has been
asking Boeing employees questions. Talking with both
a Manufacturing Support Manager and a Manufacturing
Engineer helped to determine the essential parts of these
instructions and the points which mechanics seem to
have trouble. The success of the new system depends
on the identification of trouble spots, so that the
prototype can include more detailed instructions at these
points. Comparing the current work instructions to some
of the other work instruction systems from related
literature has helped determine which aspects of
instructions have been included in other systems and
how well it worked.
SYSTEM ARCHITECTURE
The visual work instruction system consists of three
major parts: the database, the web server, and the web
browser. A SQL Anywhere database stores all of the
manufacturing plans. The web server stores the
Hypertext Markup Language (HTML) files and
processes server side script. This script is used to
retrieve information from the database based on the
requests of the user. PowerDynamo, which is marketed
by Sybase and sold with PowerSite, acts as the web
server. Finally, a web browser provides the interface to
the system for the user. Microsoft Internet Explorer
1999 Systems Engineering Capstone Conference • University of Virginia
must be used as the web browser. Figure 1 displays the
relationships between all of these components needed to
complete the prototype.
SQL
Anywhere
Database
User
Interface
PowerDynamo
Web
Server
Figure 1 - Components of the work
instruction system
Figure 1 – Components of the work instruction system
DATABASE
In order to effectively store and retrieve work
instructions, the team designed and developed a
relational database. The database design and
architecture determines how the work instructions are
stored and retrieved. Thus, the time it takes to add,
delete, update, or view the work instructions depends on
the database effectiveness. In order to ensure proper
design and development, this project followed
prescribed database development and modeling
techniques and methodologies (Watson, 1998). The
database development was divided into the following
phases: database design, physical design, and
implementation.
employees and through thorough examination of the
current work instructions:
 Part Family
 Part
 Process
 Configuration Control
 Section
 Step
 Picture
 Material
 Tool
 Best Practices
 Boeing Airplane Configuration (BAC)
The next step in developing a logical data model
was to define relationships between the entities. A
relationship is a fact or association between two entities
(Fleming and von Halle, 1989). Relationships were
used in this database to logically separate and relate
different parts of the work instructions together.
An enterprise data model was developed to display
the relationships between the entities. An enterprise
data model is a high-level conceptual model that
displays the entities and their relationships (McFadden
and Hoffer, 1991). The enterprise data model shown in
Figure 2 defines the preliminary structure of the
database.
Picture
Part Family
Part
DATABASE DESIGN
The goal of the database design phase is to develop
a logical and robust data model. The data model is
essential to the success of the database, because it
determines the basic architecture of the database.
First, the entities and their relationships were defined.
Next attributes were assigned to each entity and the
primary keys were identified. Finally, the relational
data model was developed according to relationships
between the entities and their attributes.
The first step in developing a logical data model for
this project was to determine and define the entities
needed in a work instruction database. An entity is a
person, place, thing, or concept about which you wish to
record information (Fleming and von Halle, 1989). The
following finalized list of entities was developed
through conversations with the Process Assembly MBU
Material
Process
Section
Tool
Best Practice
Configuration
Control
Step
BAC
- Denotes the many side of the relationship
- Denotes a dependent relationship
Figure 2: Enterprise Data Model
The last step in developing a logical data model was
to identify the attributes associated with each entity.
Attributes are facts or pieces of information describing
an entity (Fleming and von Halle, 1989). After all
attributes have been defined, primary keys for each
entity needed to be identified. A primary key is an
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Development Of An Integrated Manufacturing Work Instruction System
attribute or group of attributes that uniquely identifies
an instance of an entity. This enables the different parts
of the work instructions to be distinguished from one
another.
The physical database was designed using the
Enterprise Data Model from the previous section. The
physical design for the tables used the following rules:
The Table is comprised of all the attributes contained in
the entities in the Enterprise Data Model plus any
foreign keys received from tables they are related to.
The foreign key is part of the primary key of the table if
the relationship between the tables is dependent. If the
relationship is independent, then the foreign key is
added as an attribute for that table, but is not part of the
primary key (Watson, 1998). Shown below are a few
tables developed using the rules above.
Manufacturing Area
Process
Process Name (PK)
Part Name (PK)(FK)
Inherited from Part Family
USER INTERFACE DESIGN
After completing the database, the next step was
developing user interfaces for the factory mechanics
and manufacturing engineers. A quality user interface
should meet or exceed the standards set by the
following objectives (Ambler,1998 and Nielsen,1993).
1.
2.
Process Order Process Desc
Section
Section Number (PK)
Process Name (PK)(FK) Part Name (PK)(FK) Section Setup Section
Name
Desc
Inherited from Process Inherited from
Process
3.
Figure 3: Example Database Tables
In the above tables, underlined columns denote the
primary key, with PK denoting a primary key and FK
denoting a foreign key. The remaining tables were
developed with the same rules and had a similar format.
4.
The final step in the physical design was testing the
integrity of the tables. Tables were tested by using a
technique called Normalization (Codd, 1970).
Basically, these rules test the design integrity through
Normalization rules that determined if the attributes in a
table related only to that table’s primary key. Tables
were altered if they violated the following rules:
5.

6.
A database is in first normal form if each table does
not contain repeating groups and each attribute has a
unique meaning.
 A database is in second normal form if it is in first
normal form and if each non-key attribute is fully
dependent on the primary key for all tables. A nonkey attribute is any attribute that is not in the
primary key.
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A database is in third normal form if it is in second
normal form and all non-key attributes are
dependent on only the primary key.
After the design was validated through
normalization rules, the database was implemented
using SQL Anywhere.
PHYSICAL MODEL
Part Family
Part Name (PK)

Consistency throughout the system – Put buttons in
the same places and use the same color scheme.
Being consistent allows users to get accurate
mental pictures of the way the user interface works.
This decreases learning time.
Support both novices and experts – Each user
needs the system to support their needs and level of
experience.
Navigation through the interface is important – The
flow of the interface should match the flow of work
that people will do using the prototype. Since
different people do work different ways, this aspect
must also include flexibility. Shortcuts for
navigation cater to the distinction between expert
and novice users.
Word things appropriately – For example,
messages should not condemn users for making
errors. Instead the error messages should state the
problem clearly. Dialogues should contain only
relevant information. Extra information diminishes
the visibility of relevant information.
Minimize the user’s memory load – The user
should not have to remember information from one
part of the dialogue to another. Instructions on how
to use the system should be easy to retrieve when
appropriate.
Clearly marked exits – Users need to be able to
leave a screen or the entire system at any time. The
exit buttons bring the user to the beginning of the
system.
The prototype system will support both of these
users with interfaces that follow the guidelines set forth
above.
1999 Systems Engineering Capstone Conference • University of Virginia
MANUFACTURING ENGINEER USER
INTERFACE
The Manufacturing Engineer (ME) has three uses
for the work instruction system: to create work
instructions, to edit existing instructions, and to delete
existing instructions. The flow diagram below shows
how an ME would create instructions:
Digital
Camera
Video
Camera
Text
Work
Instructions
Picture
Editor
(PhotoShop)
Video
Editor
developed. Navigation capabilities are a very important
part of user interface design (Nielsen, 1993). In this
case, navigation means the different paths that users can
take to arrive at the necessary information. Users have
differing needs and learning abilities, but the system
must support all potential users. The best way to
facilitate the need for flexibility in a system is to design
several paths of navigation through the screens. Figure
5 is a high level diagram of the navigation paths for the
user interface.
Novice User
Expert User
Opening
Screen
Selection
Menu
File
Server
Web
Browser
Search
Screen
Database
Figure 4: Flow Diagram for Creating Instructions
Pictures can be taken with a digital camera and
stored as either .gif or .jpeg files. These pictures can be
edited with Microsoft Photoshop in order to mark-up
the pictures. Editing the picture will allow the ME to
highlight certain parts of the picture. After the video
and pictures are edited, they would be stored on a file
server. The ME would use a web browser to enter the
instructions into the database. The ME when entering
the instructions would enter the address of the visuals
into the database. All of the information entry boxes
which correspond to the elements in the database are
parsed into small entry menus. When entering data, a
user cannot proceed to the next menu until all of the
required information is entered. If the user tries to
proceed, an error message will be displayed. Similarly,
an alert box is displayed each time a menu of
information is successfully entered. When a user edits
data, menus of part families and sections allow easy
navigation through the maze of instructions. Each entry
in the menu is a hyper-link to more detailed menu.
FACTORY MECHANIC USER INTERFACE
Factory mechanics use the work instructions to learn
how to build parts and for future reference. The new
system allows new mechanics to use the instructions for
training and current employees to use them as quick
memory refreshers.
Before the implementation of the interface in
PowerSite could be completed, the navigation paths for
the factory mechanic to use the interface needed to be
Part
Menu
Process
Menu
Part
Menu 2
Process
Menu 2
Process
and
Part
And
Section
Process
and
Section
And
Step
Process
and
Part
And
Section
Process
and
Section
And
Step
Figure 5: Navigation paths for factory mechanic user
interface
Development and implementation of the user
interface in PowerSite requires extensive knowledge of
the relationship between the information in the database
and the interface capabilities of PowerSite. The
database contains all of the necessary information,
however, it is not in a displayable format. Using the
features of PowerSite and the supporting database, the
user interface was developed.
EVALUATION OF POWERSITE
PowerSite was used to implement the web-based
work instructions for the ME interface. PowerSite
facilitated the process of connecting to the database in
order to add, create, and delete information. PowerSite
also made it easy to visually enhance the web site. In
order to add functionality to a web site beyond these
features, a thorough understanding of JavaScript was
needed, which created many difficulties. PowerSite
provides several methods for learning how to use the
software. A well-developed tutorial leads the user
through the process of connecting a web page to a
database. Furthermore, an electronic manual is
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Development Of An Integrated Manufacturing Work Instruction System
provided, which was found to be limited in the range of
topics it covers. The web site for PowerSite, which has
the Internet address: www.sybase.com, provides a
bulletin board for developers to ask questions, but does
not provide much documentation. It should also be
noted that instructional books for PowerSite could not
be found at local bookstores or on-line web sites. The
lack of documentation made it difficult to utilize all of
PowerSite’s features.
Summary Comment on Effectiveness of PowerSite
The interface for the ME to the visual work
instruction system is functionally better suited for
Process Assembly than any of the off-the-shelf software
products that was evaluated. The prototype is better
because it is customized to the needs of Process
Assembly. Most of the off-the-shelf software products
allow the user to design the interface and edit the
pictures. Although, these options allow the user more
flexibility in creating visual work instructions, there is a
larger learning curve for the ME, which requires more
time to become acclimated to the software. In this
prototype, it is both straightforward and easy to enter
information into the database from the web. On the
other hand, as more features are added to the system,
the risk associated in developing a project increases.
New features might include the ability of the ME to edit
the pictures without a secondary tool or the ability to
access pictures from other systems. Risks include
delays in development and failure to implement desired
attributes.
The proof-of-concept system should be tested using
protocol analysis. Protocol analysis utilizes a test
subject who verbalizes his or her thoughts while
performing a process (Eberts, 1997). This verbalization
should be recorded on a video or audio tape. In the
case of the visual work instruction system, a ME should
be asked to edit or create portion of a work instruction.
The ME should talk to the observer about what he or
she is currently doing, what he or she intends to do next,
and how they feel about their actions. Points in the
process should be noted when the ME becomes
confused or when he or she has difficulty doing
something that he or she wants to do. Protocol analysis
will help identify new features that could be added to
the system as well as ways to improve the flow of the
process. A similar test should be given to the mechanic.
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CONCLUSIONS
The combination of multimedia with the current
text-based work instructions offers a tremendous
advantage. The quality of the work of the mechanics
would increase. Better quality results in fewer mistakes,
which means fewer costs associated with remaking or
fixing bad parts. Two options for implementing visual
work instructions exist for Process Assembly: buy offthe-shelf software or create their own system. A simple
system can be developed that would be easier to use for
the mechanics and MEs than off-the-shelf software as
well as more customized to the needs of Process
Assembly; however, as more features are added to the
system the risk associated in developing a project
increases. In the development of such a system, it is
recommended that PowerSite not be used as a
development tool, because it is relatively new product
that has many notable problems. If Process Assembly
desires more complexity than the prototype offers, offthe-shelf software should be considered. Techedit
offers a sound alternative for Process Assembly.
REFERENCES
Ambler, Scott W. “User Interface Design: Tips and
Techniques.” Building Object Applications that Work.
http://www.ambysoft.com/userInterfaceDesign.pdf (3
May 1998).
Codd, E. F. Relational Database Design. New York,
NY: John Wiley & Sons, 1970.
Eberts, Ray. “Protocol Analysis” (slide presentation).
http//.gilbreth.ecn.purdue.edu/~ie486/class/lecture/lect1
5/index.htm. 1997.
Fleming, Candice and von Halle, Barbera. Handbook
of Relational Database Design. New York, NY:
Addison-Wesley Publishing Company, Inc., 1989.
McFadden, Fred and Holler, Jefferey. Modern
Database Management. Redwood City, CA: Benjamin
and Cummings Publishing Company, Inc., 1991.
Nielsen, Jakob. Usability Engineering. Mountain View,
CA: AP Professional Academic Press, 1993.
Watson, Richard T. Data Management: Databases and
Organizations. New York, NY: John Wiley & Sons,
1998.
1999 Systems Engineering Capstone Conference • University of Virginia
BIOGRAPHIES
William Edwards Hancock IV is a fourth-year
Systems Engineering major from Columbia, SC,
concentrating in Management Information Systems.
His principal concentration to the project was in the
area of database design and development. Mr. Hancock
has accepted a position with Ernst & Young as a staff
consultant and will begin training in Atlanta, GA in
September.
Jon J. Handel is a fourth year Systems Engineering
major from Lafayette, CA, concentrating in
Management Information Systems. His principal
contribution to the project was the analysis of the
current work instructions. Mr. Handel has accepted a
position with Performance Engineering Corporation and
will begin working in late August, after a summer of
golf and travel.
Brandon Lucado is a student at the University of
Virginia and will be graduating with a BS degree in
systems engineering. He has had the opportunity to
work on several IT projects including a training tool
written in Visual C++ for Vector Research, Inc. and a
web site for The Boeing Company. Mr. Lucado plans
to begin his career at MicroStrategy where he will
working on data warehouse decision support solutions.
Sara E. Matys is a fourth-year Systems Engineering
major from Bowie, MD, concentrating in management
information systems. Her principle contribution to the
project is the user interface for factory mechanics. Ms.
Matys has accepted a job with Ciber, Inc. in Herndon,
VA, and will begin in late August after taking the
summer off.
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Development Of An Integrated Manufacturing Work Instruction System
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