Advanced Engineering 

Environments for 

Small Manufacturing 

Enterprises: Volume I 

Steven J. Fenves 

National Institute of Standards and 

Technology; Manufacturing Engineering 

Laboratory 

Ram D. Sriram 

National Institute of Standards and 

Technology; Manufacturing Engineering 

Laboratory 

Young Choi 

Chung-Ang University; Mechanical 

Engineering; Formerly, National Institute of 

Standards and Technology; Manufacturing 

Engineering Laboratory 

Joseph P. Elm 

Software Engineering Institute; 

Carnegie Mellon University 

John E. Robert 

Software Engineering Institute; 

Carnegie Mellon University 

May 2003 

TECHNICAL REPORT 

CMU/SEI-2003-TR-013 

ESC-TR-2003-013 

Pittsburgh, PA 15213-3890 

Advanced Engineering 

Environments for 

Small Manufacturing 

Enterprises: Volume I 

CMU/SEI-2003-TR-013 

ESC-TR-2003-013

Steven Fenves (NIST) 

Ram Sriram (NIST) 

Young Choi (Chung-Ang University/NIST) 

Joseph P. Elm (SEI) 

John E. Robert (SEI) 

May 2003 

Technology Insertion, Demonstration and Evaluation 

(TIDE) Program 

Unlimited distribution subject to the copyright. 
This work is sponsored by the U.S. Department of Defense. The Software Engineering Institute is a 

federally funded research and development center sponsored by the U.S. Department of Defense. 

Copyright 2003 by Carnegie Mellon University. 

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DISCLAIMER 

The report identifies candidate commercial off-the-shelf (COTS) products for the software components relevant 

to SMEs. The list of candidate products presented is by no means exhaustive; in the rapidly moving 

CAD/CAE/CAM software product market, only a few representative products could be identified. COTS 

components other than those mentioned here are available. The components listed herein are intended only as a 

sample of available technology as of the date of this report. Inclusion in this report is not an endorsement of 

these components by the National Institute of Standards and Technology (NIST), the Software Engineering 

Institute (SEISM), or the authors of this paper. 

NIST disclaimer: No approval or endorsement of any commercial product by the National Institute of Standards and 

Technology or by Carnegie Mellon University is intended or implied. Certain commercial equipment, instruments, or 

materials are identified in this report in order to facilitate better understanding. Such identification does not imply 

recommendations or endorsement by the National Institute of Standards and Technology or by Carnegie Mellon University, 

nor does it imply the materials or equipment identified are necessarily the best available for the purpose. Note that most 

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SM SEI is a service mark of Carnegie Mellon University. 
Table of Contents

Executive Summary................................................................................................. ix

Abstract................................................................................................................... xiii

1 Introduction....................................................................................................... 1

1.1 AEE Definition............................................................................................. 3

1.2 History......................................................................................................... 3

1.3 Purpose of Report....................................................................................... 4

2 Advanced Engineering Environments ............................................................ 5

2.1 Classification of AEEs................................................................................. 5

2.2 Basic AEE................................................................................................... 5

2.2.1 Overview......................................................................................... 5

2.2.2 Components.................................................................................... 6

2.3 Intermediate AEE........................................................................................ 7

2.3.1 Overview......................................................................................... 7

2.3.2 Components.................................................................................... 8

2.3.3 Possible extensions ........................................................................ 9

2.3.4 Applicability to SMEs ...................................................................... 9

2.4 Comprehensive AEE................................................................................. 10

2.4.1 Overview....................................................................................... 10

2.4.2 Components.................................................................................. 11

2.4.3 Applicability to SMEs .................................................................... 13

2.5 Usage scenarios....................................................................................... 13

2.6 Summary .................................................................................................. 18

3 Benefits of AEEs ............................................................................................. 19

3.1 Benefits Internal to the SME..................................................................... 19

3.1.1 Product Development and Production Time ................................. 19

3.1.2 Product Quality ............................................................................. 20

3.1.3 Cost in Product Development and Manufacturing ........................ 21

3.2 Benefits External to SME.......................................................................... 22

3.3 Summary .................................................................................................. 23

CMU/SEI-2003-TR-013 i 
4 Technical Considerations for AEE Adoption................................................ 25

4.1 Issues To Be Addressed........................................................................... 25

4.2 Choice of AEE Level and Scope .............................................................. 26

4.3 Understanding the AEE COTS Market ..................................................... 28

4.3.1 AEE COTS Solution...................................................................... 28

4.3.2 Targeted Users............................................................................. 29

4.4 Choosing COTS Products for AEE Components...................................... 30

4.5 Summary .................................................................................................. 31

5 COTS Elements of AEEs ................................................................................ 32

5.1 Classification of COTS AEE Architectural Elements................................. 32

5.2 CAD Tools................................................................................................. 33

5.3 Multidisciplinary Analysis and Optimization.............................................. 34

5.3.1 Engineering Analysis and Simulation Tools.................................. 34

5.3.2 Multiphysics Modeling and Analysis ............................................. 35

5.3.3 Optimization.................................................................................. 35

5.4 Interoperability of Tools, Data, and Models .............................................. 38

5.4.1 CAD-CAD Interoperability............................................................. 39

5.4.2 Accommodation of Legacy CAD Data .......................................... 41

5.4.3 CAE-CAE Interoperability ............................................................. 41

5.4.4 PDM-PDM Interoperability............................................................ 42

5.4.5 CAD-CAE Interoperability............................................................. 42

5.4.6 CAD-CAM Interoperability ............................................................ 43

5.4.7 CAD-PDM Interoperability ............................................................ 43

5.5 System Analysis and Synthesis................................................................ 44

5.5.1 Design Methodology Tools ........................................................... 44

5.5.2 Knowledge-Based Design Support Systems ................................ 45

5.5.3 Tools for System Analysis ............................................................ 46

5.6 Collaborative, Distributed Systems........................................................... 46

5.6.1 Support for Visual Collaboration................................................... 46

5.6.2 Support for Collaborative Product Definition................................. 46

5.6.3 OMG CAD Services...................................................................... 47

5.7 Virtual Environments, Immersive CAD, and Simulation Systems............. 48

5.8 Engineering ASP on the Web ................................................................... 49

5.8.1 CAD Data Translation................................................................... 49

5.8.2 Engineering Analysis .................................................................... 50

5.8.3 CAD and Data Repository ............................................................ 50

5.8.4 Parts Catalog Services ................................................................. 51

5.9 Summary .................................................................................................. 51

References............................................................................................................... 52

ii CMU/SEI-2003-TR-013 
Glossary................................................................................................................... 56

CMU/SEI-2003-TR-013 iii 
iv CMU/SEI-2003-TR-013 
List of Figures 

Figure 1: AEE Tool Integration................................................................................ 2

Figure 2: Model Idealization .................................................................................... 6

Figure 3: Basic Engineering Environment ............................................................... 7

Figure 4: Intermediate-Level AEE Architecture........................................................ 8

Figure 5: The NIST DPG COMPREHENSIVE AEE Architecture........................... 11

Figure 6: Retroactive Analysis Scenario................................................................ 14

Figure 7: Integrated Design-Analysis Scenario ..................................................... 15

Figure 8: Function-Driven Design Scenario........................................................... 16

Figure 9: Multifunctional Design-Analysis Scenario .............................................. 17

Figure 10: Data Interchange Map Between Application Areas ................................ 39

CMU/SEI-2003-TR-013 v 
vi CMU/SEI-2003-TR-013 
List of Tables 

Table 1: NRC AEE Elements................................................................................ 32

Table 2: Classification of AEE Components......................................................... 33

Table 3: Sample of COTS CAD and CAE Tools................................................... 36

Table 4: Interoperability of AEE Tools .................................................................. 44

CMU/SEI-2003-TR-013 vii 
viii CMU/SEI-2003-TR-013 
Executive Summary 

Small manufacturing enterprises (SMEs) can gain efficiency by integrating advanced design 

and engineering tools into the product development process. Such integration may involve 

not only the acquisition of the tools and training of the personnel to use them, but may also 

require changes to the SME’s design processes. Careful attention to issues such as tool 

integration with the design process, compatibility between multiple tools, appropriate design 

protocols, and data storage standards can maximize the interoperability between the tools and 

facilitate the creation of an advanced engineering environment (AEE). Such an environment 

can maximize design efficiency and accuracy through reduction of redundant efforts and 

enhancement of design data sharing. 

AEEs are defined as “computational and communications systems that can create virtual 

and/or distributed environments functioning to link researchers, technologists, designers, 

manufacturers, suppliers, and customers.” [NRC 99] Typically, they consist of design tools 

(e.g., computer-aided design (CAD), computer-aided engineering (CAE),), production tools 

(computer-aided manufacturing (CAM)), project management tools, data repositories 

(product data management (PDM), product lifecycle management (PLM)), and networks. 

AEEs can vary greatly in comprehensiveness, from a basic configuration utilizing limited 

CAE functions built into a CAD system, to a comprehensive configuration, maintaining a 

common database of design information accessible by all relevant design and analysis tools. 

An SME may benefit from adopting an AEE from both an internal and an external 

perspective. From an internal perspective, an AEE can offer benefits to the SME such as: 

• Schedule reduction. Product development and production schedules may be shortened 

by minimizing redundant work, enabling parametric design (i.e., a change in a design 

parameter such as a physical dimension producing a design embodying that change), 

minimizing the number of design iterations, maximizing reusability of designs, enabling 

collaboration, and improving communication; 

• Product quality improvement. Product quality can be improved by optimizing product 

design via analysis and simulation and by enhancing communication throughout the 

organization; and 

• Cost reduction. Production cost and product development cost can be reduced through 

design optimization, early problem detection and correction, and encouragement of a 

design-for–manufacturing approach. 

CMU/SEI-2003-TR-013 ix 
From an external perspective, AEEs can improve the SME’s interface to the world outside the 

company, providing the flexibility and responsiveness needed to quickly respond to the 

evolving global market. AEEs provide effective communication with customers and 

suppliers via collaboration tools and catalog facilities. 

When adopting an AEE, SMEs must consider business, technical, and organizational issues 

to achieve successful adoption and realize the business benefits. Key factors for success are: 

• clearly identified business objectives and metrics; 

• the readiness of the organization for the technology;

• suitability of the product structure; 

• executive commitment to the adoption; 

• interdepartmental communication practices; 

• AEE technology literacy and computer literacy of the staff; 

• skill levels of the design staff; and 

• risk identification management. 

The first step in successful AEE adoption is to analyze the current state of the organization. 

Once the organization’s current baseline is understood, the SME can define the targeted end 

state for AEE adoption . From this effort the SME will define the new design processes, a 

communication plan, a technology plan, a training plan, and strategies to effectively apply the 

AEE. In implementing the AEE, the SME should choose the level of AEE capability based 

on operational goals and business constraints. An evolving AEE that gradually expands in 

both scope and breadth is often the desired approach, but this can be difficult given that AEE 

tools are not always interoperable. Therefore, selection of the specific AEE elements will be 

based on a careful correlation of the technical requirements of the SME and the capabilities 

of candidate commercial off-the-shelf (COTS) tools. 

AEEs for SMEs are most often constructed through the integration of COTS information 

technology (IT) tools such as CAD, CAE, simulation, and design optimization tools. A key

aspect of the use of COTS components is interoperability, the ability of data to be shared 

among tools. Standard communication protocols and translation capabilities included in 

many tools are not always sufficient to ensure interoperability. This is often a limiting factor 

in the creation of AEEs using COTS components. Stand-alone translation tools and 

translation services are also emerging to address this need. 

A sophisticated AEE offers the SME access to improved design synthesis techniques. 

Iterative experience-based design methods can be replaced with formal design methods (e.g., 

axiomatic design theory, the Theory of Inventive Problem Solving, Quality Function 

Deployment, Design of Experiments) and knowledge-based CAD. An AEE also encourages 

x CMU/SEI-2003-TR-013 
collaboration. An inherent feature of AEEs is that virtually all data is stored in an electronic 

format. This makes it easily transportable to and available at many locations. This, in turn, 

encourages collaborative effort on design and production activities, with team members 

accessing a common design database and exchanging knowledge in real time. 

The optimization of manufacturing processes is also a powerful part of the design effort in 

an AEE-enabled environment. Virtual environments and simulation are useful tools to aid 

the designer in this process. COTS tools compatible with the other elements of the AEE are 

available to visualize and simulate workflow, operator working conditions, equipment 

utilization, etc. 

For many SMEs, the acquisition cost of the AEE components can be prohibitive. In response 

to this, the field of application service providers (ASPs) is growing. An ASP typically hosts 

AEE applications on a server and offers fee-for-service access to those applications to clients 

via the Internet. Through ASPs, SMEs can gain access to advanced IT tools on a pay-per-use 

basis without major capital investment. Today ASPs exist to provide services such as CAD 

file translation, engineering analysis services, data repository services, and parts catalog 

services. 

CMU/SEI-2003-TR-013 xi 
xii CMU/SEI-2003-TR-013 
Abstract 

Advanced engineering environments (AEEs) are computational and communications systems 

that can create virtual and/or distributed environments linking researchers, technologists, 

designers, manufacturers, suppliers, and customers, providing for the orderly integration of 

tools used and data developed during the design phase of a product. AEEs consist of design 

tools (e.g., computer-aided design (CAD), computer-aided engineering (CAE)), data 

repositories (e.g., design databases, supplier catalogs), and the networks linking these 

components and other enterprise processes. 

Although AEEs can improve the productivity of small manufacturing enterprises (SMEs), a 

key barrier to SME adoption is a lack of awareness of AEEs. This report provides an 

overview of AEE technologies for SMEs, starting with a description of the levels of AEE 

capability and a summary of the benefits of AEE technology.

AEEs for SMEs are most often constructed through the integration of commercial off-theshelf (COTS) information technology (IT) tools, but successful adoption of these tools 

requires planning and commitment. This report provides SMEs with an overview of 

technical considerations for AEE adoption to enable such planning. Interoperability of these 

tools and efficient communication between the users of these tools is also discussed. 

CMU/SEI-2003-TR-013 xiii 
xiv CMU/SEI-2003-TR-013 
1 Introduction 

Today, in many organizational settings, the concept of performing engineering tasks without a 

computer is almost unthinkable: 

• Project proposals, memos, technical reports, etc., are generated through word processing; 

• Technical research is done via the Internet; 

• Communication with customers and suppliers is accomplished via email; 

• Project schedules are developed and monitored using computerized scheduling tools; 

• Project budgets are generated and project costs are tracked using enterprise resource 

planning (ERP) systems; 

• Computer-aided drafting (CAD) tools are used to generate engineering drawings; 

• Computer-aided engineering (CAE) tools are used to analyze the behavior of product 

designs; 

• Product performance is evaluated prior to construction via modeling and simulation; 

• Engineering designs are realized using computer-aided manufacturing (CAM); 

• Electronic design automation (EDA) tools are used to generate schematics and lay out 

printed circuit boards; 

• Computer-aided software engineering (CASE) tools are used to design and manage 

software development; 

• Configuration control is maintained using product data management (PDM) systems; 

• Materials are purchased, received, and distributed using a materials requirements 

planning (MRP) system; and 

• Production workflow is planned, tracked, and managed with manufacturing execution 

systems (MES). 

The software tools used have radically changed the life of the engineer. 

If the difficult task of integrating these tools can be accomplished, the result is a powerful 

advanced engineering environment (AEE), as depicted in Figure 1. A synergy develops that 

makes the combination of these tools greater than the sum of their individual capabilities. 

Properly interfaced tools enable the user to transfer product models developed in threedimensional (3D) CAD directly to CAE tools for analysis, eliminating redundant model 

building. Printed circuit board designs may be transferred from an EDA tool to a CAE tool 

CMU/SEI-2003-TR-013 1 
for thermal analysis. The results of preliminary CAE analyses are imported into word 

processors and embedded into sales proposals, increasing their impact on the customer. 

High-bandwidth communications between members of the organization encourages 

collaboration and reduces the importance of coworkers being co-located. 

These and other factors arising from the introduction of an AEE can have far-reaching effects 

on all aspects of an organization’s structure and operation. 

Product Data 

Management

Materials Rqmts 

Planning 

Enterprise Resource 

Planning 

Computer Aided 

Software Dev 

Computer Aided 

Manufacturing 

Modeling & 

Simulation

Office 

Applications

Computer 

Aided Design

Computer Aided 

Engineering 

Electronic Design 

Automation 

SEAMLESS 

DATA 

SHARING 

Mfg. Execution 

System

Communications

Figure 1: AEE Tool Integration 

Adoption of a new technology is challenging for any organization, requiring commitments of 

capital and manpower. For new technologies these commitments are often substantial. 

Because large companies are more capable of meeting these challenges, they are typically the 

early adopters of new technologies; however, as the technology matures cost is often reduced 

to enable penetration of larger markets. When this occurs, the technology becomes 

accessible to SMEs. A recent study of SMEs ranging in size from 20 to 500 employees found 

that 75% use CAD tools and 62% use CAM tools [SPIRC 03].

2 CMU/SEI-2003-TR-013 
1.1 AEE Definition 

AEEs are integrated toolsets that enhance the productivity of participants in product 

development and production. AEEs are defined as “computational and communications 

systems that can create virtual and/or distributed environments functioning to link 

researchers, technologists, designers, manufacturers, suppliers, and customers” [NRC 99, 

NRC 00]. The physical elements of AEEs are: 

• Design tools—e.g., CAD and CAE tools; 

• Project management tools—a workflow management system used to plan, monitor and 

modify as necessary the various activities during the lifecycle of a product; 

• Data repositories—a design evolution database containing the complete description of 

the current product design and its design history, and a design repository database 

containing past product designs; 

• Networks—a design network linking the design tools and data repositories, with a 

planning gateway linking the AEE to the enterprise business functions, a production 

gateway linking the AEE to the downstream production processes, and a client gateway

linking the AEE to the end user of the product 

1.2 History 

As stand-alone engineering applications of the 1960s and 1970s began to be integrated in the 

1980s by means of shared user interfaces and/or shared internal information models, the term

“environment” and variations such as “integrated design environment” came into common 

usage to refer to such custom-built, domain-specific collections of tools and capabilities 

[Fenves 90, Fisher 89]. As the need for tools for building such environments became 

apparent, the term “framework” came into usage to refer to sets of domain-independent tools 

and components designed to assist in the construction and maintenance of environments 

[Sutton 98]. Environments and frameworks have continued to expand in number and scope 

as user needs for tighter integration increased and as strides in computing and information 

technologies vastly increased the range of possibilities. 

In anticipation of the next wave of developments, and to provide direction to these 

developments, the National Aeronautics and Space Administration (NASA) commissioned 

the National Research Council (NRC) to produce two reports on AEEs [NRC 99, NRC 00]. 

NASA and its major contractors have done considerable work on AEE components, but it

must be emphasized that the AEEs described in these reports, when they are developed and 

made operational, will fully apply only to NASA and the largest of its prime aerospace 

contractors. Small manufacturing enterprises (SMEs) are clearly small players in this array

of participants, occupying a place along the supply chain of the prime NASA contractors, 

where they would be linked into an AEE developed by the prime. 

CMU/SEI-2003-TR-013 3 
While full-fledged AEEs as described by the NRC reports appear only as a vision today,

SMEs have urgent computational and communications needs that require immediate 

attention. Furthermore, SMEs have an increasing role in the supply chains of larger 

manufacturing companies that are clearly moving toward the AEE vision. Therefore, it is 

reasonable to present architectures of engineering environments—whether advanced or not—

suitable for deployment by SMEs today that will enable transition to the engineering 

environments of tomorrow.

1.3 Purpose of Report 

This report is the first in a series of two reports addressing AEEs and their application to 

SMEs. The purpose of this two-volume report is to build awareness of the AEE concept and 

assist SMEs in evaluating the desirability and feasibility of incorporating AEEs into their 

business operations. 

Chapter 2 of the report discusses candidate architectures for AEEs and comments on their 

applicability to SMEs. 

Chapter 3 presents the benefits that may accrue to an SME from the adoption of an AEE in 

terms of internal and external effects. This chapter also discusses the technical considerations 

that affect the decision to adopt or upgrade an AEE. 

Chapter 4 discusses issues that an SME must consider when incorporating an AEE into its 

operation, such as: 

• evaluation of the current state; 

• definition of goals and strategies to achieve them; 

• definition of the AEE scope to be adopted; 

• specification of the requirements for the AEE components; and 

• selection of appropriate COTS components. 

Chapter 5 describes the general characteristics and capabilities of architectural elements or 

components for AEEs. The scope of the research leading to this paper was limited to 

geometry-centric design efforts. As such, the listed components reflect only geometry-centric 

design tools. These components are currently available or will be so in the near future. 

 

4 CMU/SEI-2003-TR-013 
2 Advanced Engineering Environments

2.1 Classification of AEEs 

The functionality of AEEs can vary widely. In this report, we utilize a three-level 

categorization, classifying AEEs as basic, intermediate, or comprehensive. Detailed 

descriptions of these levels are found in this section. 

2.2 Basic AEE 

2.2.1 Overview 

Many SMEs design and manufacture products in a mode in which the product’s form is 

determined first. Analyses to determine whether the product’s behavior matches the intended 

function are performed only later as a verification of the completed design. Of course, the 

initial form definition does not spring from a vacuum; it may come from a preliminary

analysis of a highly abstracted sketch of the product’s form or from the designer’s prior 

experience with similar products. Typically neither the designer’s experience base, abstract 

sketches, nor preliminary analyses are recorded in computer processable or retrievable forms. 

As such, the design support environment persists as if the form had been designed first. 

An SME employing this operational mode needs only the most basic form of engineering 

environment. Such an environment can be configured from no more than a CAD system and 

one or more CAE analysis tools. The product form is captured by the CAD system. This 

form may then be transferred to the CAE system for analysis of behavior. Within the CAE 

system, this model may be subjected to a process of idealization—the abstraction of the 

model to a form suitable for analysis. This often requires the simplification of the model, 

removing design detail that is appropriate in the CAD model and needed for production, but 

not significant to the analysis process. An illustration of idealization is seen in Figure 2. 

CMU/SEI-2003-TR-013 5 
Figure 2: Model Idealization 

This basic engineering environment can serve as a starting point of technology insertion for 

even the smallest SME and can be, in time, migrated to the intermediate level, as experience 

and expertise develop. Later sections of this report discuss the available alternatives, 

technical considerations, paths, and strategies involved in the migration. 

2.2.2 Components

As shown in Figure 3, a basic AEE consists of the following components: 

• CAD system. The CAD system provides a comprehensive set of tools for generating, 

manipulating, and updating the geometric form of the product being designed. In this 

architecture, it also provides persistent storage of the current, as well as previous designs. 

• Embedded analyzers. Many, if not most, CAE tool providers provide limited-capability

versions of their full-strength analysis tools embedded in the CAD tool. The advantage 

of these embedded versions is that they are directly accessible from the CAD tool 

interface and thus require considerably less setup time and user training. This makes it 

attractive and practical to invoke functional analyses at early stages of spatial design and 

use the analysis results to guide further design decisions. 

• Compatible analyzers. Embedded analyzers are often restricted in capacity and scope. 

In many cases, it will be necessary to eventually use a complete, full-capability CAE 

tool, particularly in the detailed design stage. If both the embedded and compatible CAE 

tools come from the same COTS vendor, transition from the former to the latter can be 

quite simple and natural. A CAE tool is deemed compatible with the CAD tool if it is 

capable of seamlessly receiving the spatial representation of the product to be analyzed 

from the CAD tool through a shared representation, a neutral file, or a translator. Since 

the CAD model is intended to provide information for production operations, it often 

contains more detail than is necessary for or compatible with CAE tools. The process of 

abstracting and simplifying the CAD model to make it suitable for CAE is called 

idealization or defeaturing. Idealization may be performed either within the CAD tool or 

within the CAE tool after the spatial model has been transferred. 

6 CMU/SEI-2003-TR-013 
CAD Tool 

Internal 

CAE Tool 

Internal 

Import / 

export 

Import / 

export 

Model 

generation and 

editing functions

Model 

generation 

and 

editing

functions 

Analysis

functions 

Figure 3: Basic Engineering Environment 

This is the simplest AEE possible, and is suitable for implementation by even the smallest 

SME with little or no previous experience in computer-aided design and analysis. With 

appropriate planning and choice of tools, the AEE can, in time, be upgraded to the 

intermediate level or higher.

2.3 Intermediate AEE 

2.3.1 Overview 

A potential intermediate-level AEE architecture emerges from the Core Product Model and 

the Design-Analysis Integration projects in the NIST Design and Process Group (DPG) 

([Fenves 03]). The product model architecture envisions a master information model 

containing all information about the product being designed, and multiple views of portions 

of that data relevant to specific functional domains or design disciplines. 

Two kinds of transformation occur between the core information model and the domainspecific views: 

• Models for functional analyses are extracted from the core model by idealization; and 

• Spatial models and other results generated by the analyses are transformed back to the 

core model by a process called mapping. 

The information architecture is based on two premises:

• It is possible to idealize analysis models for all functional analysis domains of interest 

from the information in the master model and to update the master model based on the 

mapping of the analysis models; and 

• Design can be initiated from any one of the functional analyses and the master model can 

be initialized from the information mapped to it from the functional analysis model. 

CMU/SEI-2003-TR-013 7 
Spatial design (traditional CAD) is just another “functional” design domain. The CAD 

model generated is just another view that can be mapped to the core model. 

2.3.2 Components

The information architecture presented above can be readily converted to a component-based 

AEE architecture by defining the components responsible for generating and maintaining the 

information models described above, as illustrated in Figure 4. 

CAD Tools 

INTERMEDIATE 

AEE 

Database 

Dynamic

... Catalog access 

PDM linkage 

Business 

processes 

Thermal

CAE Tools 

Structural AEE 

EXTENSIONS 

Figure 4: Intermediate-Level AEE Architecture 

Database. The database contains the common master information model and supports all 

concepts and data structures shared by the tools used in the design process. It is expected that 

all necessary translations can be grouped under the categories of idealization and mapping 

discussed above. Existing translators and/or standard protocols such as STEP AP 209 ([ISO 

94], [PDES 99]) may be used to support idealization, if not mapping. 

CAD system. Even though in the information architecture the spatial design or CAD model 

is treated as just another “functional” model, the reality of modern CAD-based design is that 

the CAD tool and CAD model play a key role in the design process. CAD systems provide 

comprehensive tools for generating, manipulating, and updating geometric forms, so that a 

predominant mode of design today is to create the geometric form first and later evaluate its 

behavior and compare it to the intended function. The information architecture supports this 

mode of design by allowing the geometric model and the CAD model to be one and the 

same; i.e., the idealization and mapping transformations between the CAD and core models 

are identity operators. 

8 CMU/SEI-2003-TR-013 
CAE tools. A variety of discipline-specific CAE tools, such as finite element analyzers, 

thermal analyzers, computational fluid mechanics simulators, etc., can interoperate with the 

CAD system and each other via the database. As stated before, the CAE tools receive the 

spatial representation of the product from the CAD system by way of the database. This 

occurs through idealization, which may remove features irrelevant to the analysis at hand 

(defeaturing) but may also make major modifications of the spatial model; e.g., replacing a 

solid by its medial axis transform. The CAE tool will typically build its own internal model. 

If this representation is to be returned to the database to reflect changes made in the design of 

the product, mapping, which in a sense is the inverse of idealization, needs to be performed. 

A simpler architecture results if no spatial changes are mapped back directly to the database 

and all spatial modifications are entered through the CAD system. 

2.3.3 Possible extensions 

Three extensions can be readily incorporated in the intermediate architecture. 

Catalog access facility. Short of a full-fledged function-to-form knowledge-based 

conceptual design tool or a design repository, designers in SMEs would be well served with a 

much simpler catalog access tool. SMEs could use it to access manufacturers’ and suppliers’

on-line catalogs for searching, browsing, and extracting component data in a form suited for 

direct entry in the database for representing product components. 

PDM linkage. A linkage to a PDM system that allows for (a) tracking the design process 

itself and (b) linking the completed design to the downstream manufacturing processes would 

be of great benefit to most SMEs. A further link to a Product Lifecycle Management (PLM) 

system could extend the linkage to the full lifecycle of the product, from conception to 

operation and disposal. 

Linkages to business processes. Any number of linkages to the organization’s business 

processes may be accommodated. Common linkages include: 

• A bill of materials (BOM) from the CAD system may serve as input to an MRP system; 

• Drawings from the CAD system may serve as inputs to an MES; and 

• CAD drawings may serve as inputs to a subcontract solicitation process. 

2.3.4 Applicability to SMEs 

The intermediate-level architecture is applicable to most SMEs with significant mechanical

or electromechanical design activities. It differs from the basic level primarily in the scope 

and sophistication of the CAD and CAE tools. A common configuration includes a CAD 

system and multiple interfaced CAE tools. The database function is often provided by the 

CMU/SEI-2003-TR-013 9 
CAD system’s native database facility. The user enters and modifies the spatial 

representation only through the CAD system user interface. With proper planning, this 

configuration can be extended in a number of ways, including: 

• adding further CAE tools; 

• implementing a common database independent of the CAD system’s facilities; 

• providing the extensions discussed above; and 

• providing mapping capabilities to convert the CAE tools’ internal representations to the 

shared database representation. 

2.4 Comprehensive AEE 

2.4.1 Overview 

The comprehensive-level AEE is illustrated with the NIST DPG AEE architecture. This 

architecture was developed primarily to serve as the basis for defining the standardization 

needs at the interfaces of the various component classes comprising a comprehensive AEE 

[Sriram 01]. This emerging engineering environment is seen to be distributed and 

collaborative, where designers, process planners, manufacturers, clients, and other related 

domain personnel work, communicate, and coordinate using a global web-like network. 

Designers may be using heterogeneous systems, data structures, or information models, the 

form and content of which may not be the same across all disciplines. Hence, appropriate 

standard exchange mechanisms are needed for realizing the full potential of sharing 

information models. The various applications are coordinated by a workflow management 

system using a product realization process (PRP) manager. The applications are connected 

by a design net, which provides the infrastructure for high bandwidth communications. The 

applications retrieve design data and knowledge from distributed design repositories and the 

evolving designs are stored in a database that provides snapshots in time of the evolving

design, with design artifacts and associated design rationale stored at various levels of 

abstraction. Finally, design applications communicate with other manufacturing applications

through various nets, such as the production, process planning, and user networks as shown 

on Figure 5. The classes of AAE components are further described below.

10 CMU/SEI-2003-TR-013 
Planning 

Gateway 

Planning to Production processes 

Gateway 

Traditional 

CAD 

Immersive 

CAD 

Knowledgebased CAD CAE 

Design 

Repository 

Design 

Evolution

Database

Workflow 

Manager 

to Planning processes 

Design Net 

Client 

Gateway 

to Clients 

Figure 5: The NIST DPG COMPREHENSIVE AEE Architecture 

2.4.2 Components

2.4.2.1 Applications 

The applications comprising the comprehensive AEE are as follows: 

Traditional CAD. Traditional CAD systems initially evolved out of attempts to provide 

better drafting aids. In these systems, the designer uses a computer to develop either twodimensional (2D) or 3D spatial models of the design. The drawback of traditional CAD 

systems is that they only aid in generating geometric forms. This limitation encourages 

designers to come up with the form of the product first and think about satisfying its intended 

function later (i.e., design by form-to-function transformation), an approach that can result in 

non-optimal designs. 

Immersive CAD. In immersive CAD applications, the human being becomes part of the 

design by using various immersive environments, including virtual displays and haptic 

interfaces (e.g., an instrumented glove providing input as well as force feedback, visual, and 

speech). Immersive CAD systems can aid in the evaluation of the operability and 

manufacturability of designs. With appropriate interfaces, designs can be directly modified 

to reflect the designers’ experience in manipulating the virtual prototype. 

CMU/SEI-2003-TR-013 11 
Knowledge-based CAD. Tools are needed to help designers to think in terms of function 

first, so that form subsequently results from function (i.e., design by function-to-form

transformation). Some knowledge-based design or synthesis systems implement this 

paradigm by first focusing on the symbolic aspects of design and later mapping the symbolic 

structure to a geometric model. Such systems can also capture the various semantic 

relationships between design objects. 

Analysis (CAE). CAE analysis tools such as finite element analysis tools, which focus on 

the analysis and evaluation of behavior, are closely integrated with traditional CAD systems. 

Work flow manager. The workflow management system acts as a project manager. It is 

used to plan, monitor, and modify as necessary the various design activities during the design 

lifecycle of a product and to establish and monitor project milestones. In addition, the 

workflow management system tracks the status of design documents and databases and 

enforces version control over them. 

2.4.2.2 Repositories 

Two repositories are envisioned in the comprehensive AEE, as follows. 

Design evolution database. The representation of the design as it evolves, together with all 

relevant documentation, is maintained in a design evolution database. In rare cases, the entire 

database may reside in one place and be homogeneous. More frequently, it will comprise 

distributed and heterogeneous systems, data structures, or information models, whose form

and content will generally not be the same across all applications participating in the design 

process. Nevertheless, the design evolution database must present every user with the 

information he/she needs in the format that user familiarly uses. This may necessitate 

syntactic as well as semantic translations of information passing to or from the database. 

Design repository. The design repository, the future form of historical design databases, 

replaces traditional file cabinets of drawings and documents defining past designs. The 

design repository stores descriptions of past designs, together with their rationale, in a form

suitable for browsing and retrieval for direct use in the active design process. Since design 

descriptions contain the products’ hierarchical decomposition, parts and components of 

previous products can be readily extracted for reuse. 

2.4.2.3 Networks and Gateways 

All elements of the AEE are linked via network connections. The design net is the active link 

between the diverse agents and repositories, which may all be geographically distributed. 

12 CMU/SEI-2003-TR-013 
The process planning gateway links the design environment with the downstream activities. 

The link is bidirectional: not only are design decisions communicated downstream, but 

information from manufacturing process planning and other tasks are brought upstream to 

bear on the design. 

The production gateway links the design environment with the production environment in a 

two-way fashion so that, for example, production experience on a previously designed 

product can be recorded in that product’s description in the design repository for future 

browsing or use. 

The client gateway links the engineering environment to the product’s users. Customer 

needs, specifications, requirements, and evaluations flow from customers to designers, while 

engineering specifications, proposals, prototype designs, etc. flow from the designers to the 

users. 

2.4.3 Applicability to SMEs 

The NIST DPG comprehensive-level architecture, like the NRC AEE architecture, is not 

directly applicable to SMEs who wish to develop an AEE for their own internal use. As 

comprehensive-level AEEs evolve from current prototypes in large aerospace and automotive 

manufacturing organizations, SMEs will eventually become connected into an AEE of the 

scope described above. This, however, would occur as they become incorporated into the 

supply chain of a major prime contractor. In such a case, the SME would link to the AEE 

designed and implemented by the prime through the appropriate network(s) described above. 

Hosting of the AEE elements could be distributed between the SME and the prime contractor, 

with the AEE elements used most intensively (e.g. traditional CAD, CAE) being hosted at the 

SME’s site. Data repositories could also be distributed or replicated at multiple sites. 

2.5 Usage scenarios 

AEEs may be used in a variety of ways by a design organization. Some possible usage 

scenarios are illustrated below.

The simplest scenario is the retroactive analysis scenario, as illustrated in Figure 6. 

Unfortunately, this non-optimal process is followed much too frequently. In this scenario, the 

spatial design is completed before any functional analysis is undertaken. The candidate 

design is advanced through the preliminary and detailed design stages based on designer 

experience and knowledge. The designer validates the design via analysis only after the 

completion of the detailed design stage. To accomplish this, he idealizes the model by

eliminating information not needed for analysis, either due to limitations of the analysis tools 

or because the mass of detail may hide important aspects of the design’s behavior. If the 

CMU/SEI-2003-TR-013 13 
analysis results are satisfactory or nearly satisfactory, the designer completes the final design 

as planned. If the analysis results are unsatisfactory, the designer must return to the detailed 

design or even preliminary design stages to resolve the deficiencies. Another iteration of 

analysis then follows. This retroactive analysis approach may result in overdesign—to 

reduce the expense or delay of design iterations caused by inadequate behavior revealed by

analysis—and/or multiple cycles of prototype building, testing, and modification. 

Designer Analyst

Final design 

Detailed design

major

change minor change satisfactory

Design changes unsatisfactory Evaluation

Idealization

Preliminary design

Conceptual design

Detailed analysis

Figure 6: Retroactive Analysis Scenario 

A more proactive and more effective scenario involves analyses at earlier stages so that 

analysis results may guide subsequent design decisions, as illustrated in Figure 7. As users 

develop more analytical experience and judgement, they often evolve from the retroactive 

analysis scenario to this one. In this integrated design-analysis mode, the designer analyzes 

the product throughout the design process. After completion of the preliminary design, the 

designer idealizes the model as it exists at that stage and analyzes the performance. If the 

performance is satisfactory, the designer proceeds to the detailed design stage with 

confidence. If not, he revises the preliminary design and reiterates the analysis. Due to the 

absence of detail in the preliminary design stage, design modification/analysis iterations can 

be performed quickly. In the detailed design stage, the designer adds the necessary model 

detail to suit the needs of the production processes. This detail addition causes significant 

14 CMU/SEI-2003-TR-013 
expansion of both the complexity and size of the product model. At the completion of the 

detailed design stage, the designer again analyzes the product performance. To accomplish 

this, he must suppress much of the added design detail and idealize the model to make it 

suitably simple for analysis. If the analysis predicts satisfactory or near satisfactory

performance, the designer may complete the final design. If not, he must repeat the detailed 

design stage; it is highly unlikely that he/she will have to revisit the preliminary design stage 

to correct the deficiencies. The chances of major redesigns indicated by analyses of detailed 

designs can thus be significantly reduced. 

Conceptual design

Detailed design Detailed 

analysis

Designer Analyst

Preliminary design

Design changes Evaluation

Final design 

unsatisfactory

satisfactory

major

change

Preliminary

analysis

Design changes Evaluation unsatisfactory

major

change

satisfactory

Idealization

Feature 

suppression 

& Idealization

minor

change

minor

change

Figure 7: Integrated Design-Analysis Scenario

The scenarios shown in Figure 6 and Figure 7 only use idealization transformations; changes 

to the spatial model are made only through the CAD system. If it is desired that spatial 

changes be made through the analysis models as well, then mapping transformations need to 

CMU/SEI-2003-TR-013 15 
be implemented. If one or more of the functional analysis tools are converted to conceptual 

or preliminary design tools, the scenario of function-driven design shown in Figure 8 

emerges. In such a function-driven design mode, the product engineer begins with a 

functional design of the product, rather than with a form-based design, and translates the 

functional design into a physical form. This form becomes the starting point for the product 

designer. He proceeds with the preliminary and detailed design efforts much the same as in 

the integrated design-analysis mode. 

Engineer Designer Analyst

Function-to-form

transformation

Mapping 

Preliminary 

design

Preliminary 

analysis 

Design

changes 

Evaluation unsatisfactory

major

c

s

hange

minor

change

atisfactory

Idealization

Detailed 

design

Detailed

analysis 

Evaluation Design

changes 

Final design

unsatisfactory

m satisfactory inor 

change

Feature 

suppression 

& idealization 

Conceptual

design

Conceptual 

Functional

design

major

change

Figure 8: Function-Driven Design Scenario 

16 CMU/SEI-2003-TR-013 
Finally, multiple functional analyses (structural, thermal, dynamic, etc.) may be introduced, 

in parallel or sequentially, resulting in the scenario shown in Figure 9. Like the functiondriven design scenario of Figure 8, this multifunctional design-analysis scenario begins with 

a conceptual design to meet specified functionality. This functional design is mapped to a 

physical conceptual design and then subjected to various analysis processes. More detail is 

added to the design as it progresses through the conceptual, preliminary, detailed, and final 

design stages. Within each design stage, the functionality of the design is analyzed and 

evaluated with respect to specified requirements and, if necessary, the design is iterated 

before proceeding to the next stage. 

Engineer Designer Analyst 

Conceptual

design

Function-toform transform

Conceptual

Functional

design

Mapping

Preliminary design 1

Preliminary design 2

Analysis A

Analysis B

Reconciliation

Detailed design 1 

Detailed design 2

Analysis 

C, D 

Analysis 

... Reconciliation

Final design

Each analysis block 

represents a cycle of 

idealization, analysis, 

evaluation, modification

and mapping in one

analysis domain. 

Opportunistic analysis 

tracks status of design for

each domain and invokes

analysis when 

preconditions are met. 

Figure 9: Multifunctional Design-Analysis Scenario 

CMU/SEI-2003-TR-013 17 
2.6 Summary 

Three levels of architecture of AEEs have been presented. The basic level is easily

implemented by the smallest SME and requires nothing more than two well-matched COTS 

software products. The intermediate level can also be implemented by SMEs, but requires 

some data integration. Architectures of similar complexity have been implemented by and 

are operational in many large and medium-size manufacturing entities, albeit without the 

tight data integration presented here. The comprehensive level, like the AEE described in the 

NRC reports, has not been fully implemented anywhere and serves primarily as a roadmap of 

future developments and standardization efforts at the component interfaces. 

18 CMU/SEI-2003-TR-013 
3 Benefits of AEEs 

3.1 Benefits Internal to the SME 

The adoption of an AEE affects many aspects of an SME’s business both in the short- and 

long-term perspectives. The short-term benefits may be more easily measured, quantitatively

or qualitatively, than long-term benefits. Although there are many areas of business where 

introducing or upgrading an AEE has an impact, the operational benefits can be generally

classified into three categories: 

• product development and production time reduction; 

• product quality improvement; and 

• cost reduction. 

3.1.1 Product Development and Production Time 

AEE components, singly or in combination, can significantly reduce product development 

and production times via the following methods: 

Provide accurate and rapid response to RFQs. In the current globally connected business 

environment, rapid and accurate response to a customer Request for Quotation (RFQ) is one 

of the crucial elements to remaining competitive in the market. The use of rapid design tools

and catalog search facilities can help to respond quickly to requests from customers. 

Integrated analysis tools are also useful to quickly assess whether the proposed configuration 

meets the key engineering requirements from the customer. 

Minimize duplicated and repetitive work. Substantial amounts of product development time 

can be saved by eliminating, or at least minimizing, duplicate and repetitive work in the 

design process. Parametric design technology not only facilitates the initial design process, it 

also provides great convenience if redesign with minor modifications is needed later. PDM 

and PLM tools for managing the design process and data are also useful for facilitating reuse 

of previous designs. 

Reduce the number of design iterations needed for successful design. Design iterations are 

inevitable during design, analysis and refinement. However, if functional analyses/evaluations are performed earlier in the design process, the number of iteration cycles and design 

CMU/SEI-2003-TR-013 19 
time can be reduced. Moreover, the SME can reduce the number of design iterations by

using previous functional analyses/evaluations for similar designs. Extensive analyses and 

simulations at the design verification stage can drastically reduce—but probably never fully

eliminate—the need for physical prototyping and testing. 

Maximize reuse of designs and design elements. Significant reductions in development time

can be achieved by the reuse of previous designs or design elements. Reuse has always been 

practiced, but with designs stored in notebooks or file drawers and poorly archived, the time 

taken to retrieve a design was often more than the time taken to design it from scratch. With 

the database tools of AEEs, there is an opportunity to index, search, and retrieve previous 

designs according to a wide range of criteria, thereby significantly reducing development 

time. 

Improve interdisciplinary communication and collaboration. Various collaboration tools in

the design process can also reduce design time. The use of collaboration tools in the design 

process with various engineering disciplines will reduce design/manufacturing 

misunderstandings, thus reducing physical testing and design/prototyping iterations, process 

risks, and potential delays. Collaboration tools are particularly valuable when problems are 

encountered at the manufacturing or assembly stages, and rapid re-designs/re-analyses are 

needed to rectify the situation. 

The tight integration of engineering processes, including CAD, CAE, and CAM, will 

contribute to shortening the product development cycle. The software integration 

technologies and smooth standards-based data interchanges that are adopted in many of the 

CAD/CAM/CAE tools eliminate unnecessary rework and potential sources of error in data 

preparation for sequences of engineering processes. 

3.1.2 Product Quality

The use of an AEE linking analysis and simulation tools not only reduces the product 

development cycle by eliminating prototypes and extensive physical tests, but also greatly

enhances the quality of the products developed via the following methods: 

Enhanced Depth of Performance Analysis. The low cost of simulations and quick 

design/simulation iteration cycles provided by AEEs allow design teams to thoroughly 

investigate the functional quality of a product before it is manufactured. It has often been 

observed that this capability of quickly evaluating whether the designer’s intent is satisfied is 

most critical in the earliest stages of conceptual design, where the designer attempts to 

synthesize a form to satisfy the most critical functional requirements. An AEE CAD 

component that can accept a coarse, almost sketch-like form description and an embedded 

CAE analyzer that can simulate the behavior of the product at this level of detail can be of 

great value in properly initiating the design process. 

20 CMU/SEI-2003-TR-013 
Optimization of Final Design. For subsequent, detailed stages of design, multiple levels of 

simulation tools are available for various requirements. The most basic and popular are 

general-purpose finite element analysis (FEA) tools. Specialized FEA tools are also available 

in the areas of non-linear analysis, mold flow analysis, metal forming, casting analysis, fluid 

dynamics analysis, etc. System analysis tools also contribute to the enhancement of product 

quality. Multi-disciplinary analysis and optimization tools are another category of tools for 

quality enhancement. Some optimization tools automate iterative analysis with numerical 

optimization, exploratory search, and expert system approaches. 

Improved Collaboration in Early Design Stages. AEEs also provide important means for 

effective collaboration at the earliest design stages between designers, analysts, and 

manufacturing engineers. This allows the design team to reflect all aspects of the product 

development process in the design so that later design changes are minimized. Last-minute 

design changes greatly affect the cost and quality of products. A number of collaboration 

tools are available from commercial sources. 

Expanded Reuse of Proven Designs. Design reuse, mentioned above, can also increase 

product quality, in at least two ways. First, by extending the database of previous designs 

with information about each product’s performance and success in the marketplace, searches 

and retrievals of previous designs for use in new situations can be restricted to successful 

products only. Second, by exercising design reuse within one product, the number of 

different kinds of product components such as bolts or switches can be greatly reduced, 

increasing the product’s maintainability.

Enhanced Methods of Quality Evaluation. Increased product reliability can be achieved 

through quality engineering tools, reliability-based design and optimization, and tools for 

robust design. 

3.1.3 Cost in Product Development and Manufacturing 

Cost reduction is one of the most important issues to maximize the profit in a manufacturing 

enterprise. Cost reduction can be achieved in many ways; however, this report deals only

with issues related to the engineering aspects supported by AEEs. Ways in which AEEs can 

produce cost reductions include the following: 

Design Optimization. The most immediate and direct cost reduction in a product can be 

achieved by design optimization. In most cases, the target functions for the optimization are 

related to cost. Combinations of various analysis and optimization tools can be used for 

specific optimization targets. Manufacturability and cost analysis tools also can be utilized at 

the early stages to save on product costs. Design reuse, as discussed above, can also reduce 

product cost by minimizing the number of different kinds of product components.

CMU/SEI-2003-TR-013 21 
Risk Reduction through Design Experiments. Design experiments at early stages of the 

design process reduce product development cost. Analyses, functional simulations, assembly

and manufacturing simulations all contribute to the early detection of potential design 

problems. Nearly 80% of the product cost is committed in the conceptual and preliminary

design stages, while most of the actual cost is incurred in the production stage. Also, the ease

of making design changes is dramatically reduced once the design is in the detail design 

stages. Therefore the early detection of potential design problems is crucial to reducing lead 

time and cost. 

Manufacturing Optimization through Simulation. Factory/manufacturing simulation tools 

can save substantial amounts of funds invested in production facilities. Manufacturing 

system simulation tools are used for determining the optimal equipment configuration and 

layout; troubleshooting existing systems, including identifying bottlenecks in the operation; 

and testing equipment controls prior to installation. These simulations lead to direct savings 

in capital investment and enhanced productivity.

3.2 Benefits External to SME 

AEEs provide benefits to the SME that are visible to external customers and suppliers. These 

benefits help the SME in a strategic sense in that the external customers and suppliers 

perceive a higher level of capability or responsiveness from the SME, as described below.

Coping with Global Enterprises and Markets. AEEs permit SMEs to provide quick response 

to the competitive global market in every aspect, including RFQ response, quickly changing 

market demands, and shortened product life. Flexibility can be accomplished by carefully

implementing AEEs to provide detailed and timely information that is suitable for the SME’s 

individual needs. 

For example, consider an SME that competes in a small market by specializing in high 

performance systems in an aerospace domain. The SME may create an AEE that enables 

timely and technically detailed information to be placed into proposals. In this case, the AEE 

is providing the SME with the capability to cost-effectively communicate confidence in a 

proposed design to customers who are most concerned with technical performance. 

Communication with Customers and Suppliers. Effective communication with customers 

and suppliers can be achieved with various collaboration tools and catalog facilities within an 

AEE. Efficient technical communication between customers and suppliers not only reduces 

the development time, but also enhances the quality of the product. Therefore, enabling close 

and efficient technical collaboration upstream with suppliers and downstream with customers 

improves competitiveness. 

22 CMU/SEI-2003-TR-013 
For example, an SME that adopts a 3D CAD tool that supports a common data standard can 

use this information to support supply chain communication. If a part must be manufactured 

at another location (outsourced), the 3D CAD tool can generate a data file that can be sent to 

the supplier to automatically generate a CAM file to manufacture the part. Additionally, the 

SME can send the final 3D CAD file to the customer to ensure the product integrates into a 

larger assembly. 

3.3 Summary 

Some of the benefits an AEE can offer to an SME include: 

• Reduction in product development time. AEEs encourage and support design

reuse and parametric design processes, eliminate redundant efforts during the design 

process, encourage functional analysis earlier in the design cycle, and encourage

collaboration among designers, engineers, manufacturers, suppliers, and customers; 

• Reduction in production time. AEEs enable design optimization by eliminating 

overly conservative assumptions. They minimize component inventories by

encouraging and supporting design reuse. They also enable process designers to 

simulate and optimize manufacturing processes during the product design stage 

• Improvement in product quality, AEEs encourage and support functional analysis 

and simulation prior to manufacturing. They enable design optimization by

evaluating the impacts of design trade-offs. They validate design performance prior 

to manufacturing. They encourage and support multi-disciplinary collaboration 

among designers, engineers, manufacturers, suppliers, and customers. They

encourage and support reuse of existing successful designs. They enable the use of 

advanced simulation techniques such as Monte Carlo and Taguchi methods 

• Reduction in product cost. AEEs enable design optimization, eliminating costly, 

overly-conservative assumptions. They encourage and support design reuse, 

minimizing the required component inventory. They enable process designers to 

simulate and optimize manufacturing processes during the product design stage 

• Reduction in product development cost. AEEs create reductions in the product 

development schedule (see above). They detect functional problems earlier in the 

design process, when they are less costly to fix. They encourage and support design 

experiments early in the design process 

• Improved market agility. AEEs enable the SME to cope with rapidly changing

global market demands and competitive environments 

• Improved communications. AEEs provide a means of improving communications 

with both customers and suppliers, strengthening the supply chain.

CMU/SEI-2003-TR-013 23 
24 CMU/SEI-2003-TR-013 
4 Technical Considerations for AEE 

Adoption 

4.1 Issues To Be Addressed 

The following is a brief outline of the technical issues that an SME needs to consider before 

adopting or implementing an AEE. Primary emphasis is placed on the engineering process 

within the enterprise, and to the design activities within that process. Similar issues may

arise from the marketing, manufacturing, and service processes. Depending on the scope 

anticipated for the AEE, such issues may have to be combined with the purely engineeringand design-oriented issues.

Evaluation of current state. The first consideration is the creation of an up-to-date and 

accurate evaluation of the firm’s current state. Key aspects of such an evaluation are: 

• the current mix of products, particularly their similarities, differences, and potential for 

creating product families; 

• the degree of integration and level of communication with marketing, manufacturing, 

service, etc., as well as with customers and suppliers: paper and telephone; electronic 

transfer and e-mail, PDM, PLM, etc.; 

• the current level of computer use, e.g., none, isolated design/analysis/manufacturing 

applications, basic AEE, or intermediate AEE; 

• the current skill and knowledge level of in-house designers, engineers, and analysts, as 

well as external consultants available to the SME; and 

• perceived problems for which AEE adoption or enhancement is a potential solution, e.g.,

time delays, cost overruns, communication bottlenecks, product quality and variability. 

Definition of goal state. The next consideration is to attempt to define, as clearly as possible 

at this stage, the expectations of the changed conditions and modes of operation that the 

adoption or upgrading of an AEE may bring to the organization. Such a definition must be 

driven by clear business objectives, and is best organized along the five axes used for 

describing the current state used above, as follows: 

• intended mix of products, whether to retain present mix, expand or contract it based on 

technical considerations, or create a hierarchy of product families; 

CMU/SEI-2003-TR-013 25 
• intended degree of integration and communication, which may range from further 

retrenchment to increased levels of both data and process integration within the 

organization (e.g., cross-train designers, analysts, and engineers or integrate/disperse 

design functions), and beyond (e.g., various forms of partnering with suppliers and 

customers); 

• intended level of computer use according to the scale given above (specifics of the AEE 

to be adopted will not be known at this stage, but a preliminary target level may be 

defined for the different roles involved);

• skill and knowledge need inventory and training needs, to correspond to target levels of 

professional activities; and 

• strategies to address and overcome perceived problems uncovered. 

With the current and goal states identified and documented, the strategic plan to move from

the former to the latter can be initiated. The succeeding sections discuss briefly the technical 

considerations that enter into the strategic plan. 

4.2 Choice of AEE Level and Scope 

Levels. As discussed in Chapter 2, AEEs may be categorized into three levels based on their 

capabilities as basic, intermediate, or comprehensive AEEs. 

Full-fledged comprehensive AEEs do not exist at the present time. The NRC defines them as 

goals [NRC 99], while the NIST architecture is intended to identify interfaces for potential 

standardization. [Sriram 01] Although not yet complete, the engineering environments 

presently in place at some of the largest aerospace, automobile, and shipbuilding enterprises 

are reasonable approximations of the NRC AEE concept. 

Intermediate-level AEEs constructed of COTS software components are routinely used by the 

majority of mid- to large-scale manufacturing enterprises. These environments are by no 

means standardized, and exhibit a large range of variation in at least three respects: 

• breadth in terms of the number and kind of design subdisciplines supported; 

• depth in terms of levels of the design process (e.g., conceptual, preliminary, detailed) or 

divisions of the organization supported (e.g., marketing, manufacturing, service); and 

• degree of data integration among the environment components, ranging from fully 

integrated databases supporting all components to totally disjunct components 

communicating through files or messages. 

Breadth and depth will collectively be referred to as the scope of the AEE. 

26 CMU/SEI-2003-TR-013 
Local engineering environments, routinely found in even the smallest manufacturing 

enterprises, typically consist of a CAD tool that also serves as the data repository and a 

discipline-specific CAE tool or, at most, a few such tools. In the mechanical manufacturing 

area, the CAE tool is, almost without exception, a finite element analysis tool for evaluating

mechanical behavior in terms of stresses and displacements. 

Direction of evolution. The choice of an appropriate AEE to effectively and efficiently

support an SME’s goal state will generally be some combination of: 

• expanding the scope of the current environment; 

• moving up a level in the AEE hierarchy; and 

• increasing the degree of data integration. 

Moves of more than one level in the AEE hierarchy, e.g., moving from a manual environment 

to an intermediate AEE level, are not encouraged, as there are too many conceptual and 

practical steps involved that are only learned by extended practice and exposure to the next 

higher level. 

The most common move direction is expansion of scope. Additional CAE analyses beyond 

those incorporated in the environment, as well as additional linkages to other phases of the 

product development process, frequently co-exist within an organization for considerable 

amounts of time before they are integrated into the environment. At other times, 

developments external to the engineering group necessitate expansion of the environment in 

breadth or depth or both. Finally, changes in the marketplace, such as the introduction of new 

products and services, may warrant expansion of scope by the addition of new tools. 

Explicit moves up the hierarchy may be warranted by either internal or external factors. The 

prime internal factor is the desire or need to move from an unstructured collection of tools to 

an integrated suite and eventually to full interoperability among the tools. A major 

component of this migration, the need for increasing the degree of data integration, is 

discussed separately below. External (to the engineering function) factors driving the move 

to a higher-level environment may be internal to the organization (e.g., increased scope of 

engineering design activities, closer linkage to other corporate activities), or external (e.g., 

tighter linkages along the supply chain, increased dependence on application service 

providers (ASPs)). In general, a move to a higher-level environment is warranted whenever 

there is increased need for the full set of tools to “speak as a single voice” with the external 

world. 

The means of communication among the tools comprising an engineering environment vary

enormously, from manual transcription of the output of one program to the input of another 

one—presumably a rarity today—through file transfers with or without standard formats 

and/or translations, to preprogrammed application program interfaces (APIs) on to full 

CMU/SEI-2003-TR-013 27 
interoperability. A common form of upgrading or migrating an engineering environment is 

by increasing the degree of data integration among the applications. One way of 

accomplishing this is through the introduction of shared databases. Databases have the 

further advantage of providing integrity and versioning controls, and can eventually evolve 

into searchable repositories of the organization’s past successful designs. 

4.3 Understanding the AEE COTS Market 

After an SME determines the desired level of AEE capability, the SME must examine 

available AEE components within the AEE market, select specific AEE COTS components 

and execute an AEE technology adoption plan. This section provides general concepts 

concerning the AEE COTS market. The next section provides a partial set of references to 

available resources for evaluating and selecting AEE COTS components. Chapter 5 presents 

the range of AEE COTS components in greater detail in order to increase awareness and 

focus attention on critical interoperability issues. 

4.3.1 AEE COTS Solution 

The significant consolidation within the AEE COTS market has resulted in many AEE 

vendors partnering with other vendors to provide a complete COTS solution for a 

manufacturer. This leads SMEs to decide between pursuing an AEE COTS solution from one 

vendor or combining a suite of AEE COTS components from multiple vendors. Each path 

has benefits and weaknesses. 

If an SME adopts an AEE COTS solution from one vendor, this approach minimizes some of 

the COTS component interoperability issues. In addition, the SME only contracts support 

from one vendor and simplifies employee training, because the vendors’ AEE tools often use 

common interfaces. However, this approach is typically a larger initial investment and 

increases the SME dependency on the COTS vendor. Specifically, the SME must follow the 

updates and product changes from that one vendor. In addition, if the SME determines that 

an AEE component is not suitable and considers a component from another vendor, the 

interoperability with AEE tools outside the COTS solution may be very limited. 

The SME can also choose to combine several AEE components from multiple vendors into a 

custom AEE, but this approach also raises issues. The interoperability across AEE 

components is not ensured by any one vendor, so this becomes the responsibility of the SME. 

The SME must also deal with multiple vendors and plan training to support multiple 

products, which may have different user interfaces. One key benefit of this approach is that 

the SME can start small and grow incrementally by choosing the specific AEE components 

that are the best fit for its needs. 

28 CMU/SEI-2003-TR-013 
The technical considerations in configuring an AEE are largely component- or design 

function-specific. It is taken for granted that in the engineering organization of any

manufacturing concern, a CAD tool will be the primary AEE component generating, 

visualizing, communicating, and modifying the physical form and the assembly of designs, as 

well as one of the primary linkages, with PDM or PLM, to manufacturing and CAM. CAD 

systems are categorized into entry, “light,” and “full strength” levels, with substantial, if not 

complete, compatibility between the last two. 

A further consideration in choosing a COTS tool is often interoperability with customers. 

SMEs frequently serve as subcontractors to larger prime contractors. In an effort to 

maximize interoperability and data sharing, some prime contractors mandate the use of 

specific COTS tools. This can be a significant difficulty for a small manufacturer, forcing 

him to adopt a new tool that may not be the best fit for its operation. This is further 

complicated when dealing with multiple prime contractors, each with its own preferred tool 

set. Fortunately, this occurrence is rare. AEE tool vendor implementation of data 

interchange standards such as STEP is improving data sharing capabilities among different 

tools, but this is an evolutionary change that requires buyers to thoroughly test AEE tool 

interoperability before committing to a specific tool. 

4.3.2 Targeted Users 

AEE tool vendors tend to have a variety of products that target a range of users. For SMEs, it 

is important to understand the targeted users of an AEE COTS tool and the level of training 

required to use the tool. 

For example, some CAE tools are complex and provide a wide range of functionality because 

they are targeted at analysts or lead engineers. However, many CAE tool vendors also sell 

lower cost tools that have been simplified to target engineers or designers. A common 

practice by vendors is that in addition to a full-fledged CAE tool, they provide a simplified 

version embedded in and compatible with various CAD systems. These embedded tools have 

limited capabilities, but are easier to learn and use. They are appropriate for use by designers 

and engineers in the conceptual and preliminary stages of the design process, even if the fullfledged version needs to be used by analysts later for detailed design and product verification. 

As other analysis technologies mature and become available to the designers (e.g., 

computational fluid mechanics, multiphysics, mathematical optimization), it can be expected 

that they will be either added to current tools or become available as separate AEE 

components. 

Increasingly, PDM will become an essential AEE component, in either embedded or 

integrated form, both for the control of the design process itself and for the integration of the 

engineering function into the total product delivery system. It is to be expected that PLM will 

CMU/SEI-2003-TR-013 29 
in short order also become an important AEE component, even for the smallest 

environments. 

Chapter 5 presents COTS examples of potential AEE components.

4.4 Choosing COTS Products for AEE Components 

There is a substantial body of literature on the topics of the evaluation of COTS products and 

of constructing systems comprised of COTS components [Carney 98]. Although much 

discussion of COTS evaluation is general in nature, a relevant example in the manufacturing 

domain is [Brownsword 00]. This literature can be used for choosing AEE COTS products 

as well, with a few important provisos: 

• There is typically less customization of the COTS products in this area than in other 

application domains, such as commerce or management; 

• Documentation is important, as always, but in addition to traditional forms of 

documentation, it is particularly important to have clear and credible documentation of 

the theoretical basis of the product, elaborated through numerous examples; 

• The degree of support and training from the vendor and the availability of local expertise 

on the product are very important selection factors; and 

• Similarly, the popularity of the tool and the upgrade plans of the vendor are important 

factors. 

The last two factors imply a degree of conservatism of the AEE users. Such conservatism is 

amply warranted by the ethical and professional responsibilities of engineers and designers 

for the products they design. This responsibility cannot be relegated to the tools they utilize. 

In addition to the general COTS evaluation criteria mentioned above, the evaluation must 

include technical criteria relevant to AEE. For example, a common CAE component is FEA. 

The technical considerations in choosing the appropriate FEA tool are many: 

• Will non-linear analyses be needed? If so, what kinds (material and/or geometric 

nonlinearities)? 

• Will dynamic analyses be needed? If so, what kinds (modal, harmonic, time-domain, 

frequency-domain)? 

• Will specialized finite elements and processing capabilities be needed (e.g., thick-walled 

cylinders, sheet metal)?

• Will special types of pre- and post-processing be needed? 

These technical issues are sometimes difficult for SMEs to identify, but Chapter 5 provides a 

summary of common criteria. 

30 CMU/SEI-2003-TR-013 
4.5 Summary 

Technical factors to be considered when adopting an AEE include: 

• evaluation of the current state of the SME to determine the current mix of products, 

degree of internal integration, current level of computer use, current skill and knowledge 

levels, and perceived problems; 

• definition of a goal state, including the desired future state of the SME, and the strategies 

to overcome the perceived problems; 

• definition of the scope and level of the AEE to be adopted, based on the foregoing 

evaluations; 

• specification of the requirements for the components of the AEE; and 

• selection of the COTS AEE components satisfying the requirements. 

CMU/SEI-2003-TR-013 31 
5 COTS Elements of AEEs 

5.1 Classification of COTS AEE Architectural 

Elements

The NRC identifies AEE components and their characteristics in three categories, as shown 

in Table 1 [NRC 99]. The check-marked entries are considered to be relevant to this report 

and are listed with references to the sections in which they are discussed. 

Table 1: NRC AEE Elements 

√ 1. Computation, Modeling, and Software 

√ A. Multidisciplinary analysis and optimization Section 5.3 

√ B. Interoperability of tools, data, and models Section 5.4 

√ C. System analysis and synthesis Section 5.5 

√ D. Collaborative, distributed systems Section 5.6 

E. Software structures that can be easily reconfigured 

2. Human-Centered Computing 

A. Human-adaptive interfaces

√ B. Virtual environments Section 5.7 

√ C. Immersive systems 

D. Telepresence

E. Intelligence augmentation 

3. Hardware and Networks 

A. Ultrafast computing systems 

B. Large high-speed storage devices 

C. High-speed and intelligent networks 

Chapter 2 defines three levels of AEEs and their respective components. The correspondence 

between the NRC AEE components and those previously identified is shown in Table 2. 

While all the components listed in the NRC report need to be exploited for full-scale AEE 

systems for large manufacturing organizations such as Boeing or General Motors, SMEs need 

only a portion of the components identified. When it comes to the urgent and short-term

implementation needs of SMEs, currently available AEE components are very limited. The 

goal of this report is to identify candidate COTS products for each AEE software component 

32 CMU/SEI-2003-TR-013 
relevant to SMEs, with increased specificity and breadth at the intermediate and 

comprehensive levels. 

The presentation is generally organized according to the classification of the NRC report. 

Table 2: Classification of AEE Components 

SOURCE

Engineering 

Function 

NRC AEE Comprehensive

AEE level 

Intermediate

AEE level 

Basic 

AEE level 

Form Capture • Not specifically 

addressed 

• Traditional 

CAD 

• Traditional CAD • Traditional CAD

Functional 

Analysis 

• Multidisciplinary

analysis, 

optimization 

• System analysis 

and synthesis 

• Knowledgebased CAD 

• CAE Tools 

• Immersive 

CAD 

• CAE tools • Embedded 

analyzers 

• Compatible 

analyzers 

Process 

Management 

• Not specifically 

addressed 

• Work flow 

manager 

• PDM linkage • Not specifically 

addressed 

Data Storage • Large high-speed 

storage devices 

• Interoperability of 

tools, data, and 

models 

• Design 

evolution

database 

• Design 

repository

• Design database 

• Design repository

• Catalog access 

facility

• CAD database 

Human Interface • Virtual environ. 

• Immersive systems

• Immersive 

CAD 

• CAD interface 

• CAE interface 

• CAD interface 

• CAE interface 

Communications • Collaborative, 

distributed systems

• Interoperability of 

tools, data, and 

models 

• Design net 

• Process 

planning net 

• Production net 

• Client net 

• Local area 

network (LAN) 

• Internet 

• LAN 

• Internet 

5.2 CAD Tools 

Geometric CAD tools, not specifically discussed in the NRC report, are among the most 

important and widely used COTS components. Most current geometric CAD tools support 

feature-based parametric modeling, with some small variations in the capabilities among 

them. The choice of the right CAD tool depends on a number of different concerns, 

including current design practices, budget, the software environment, the main product line of

the SME, available add-on modules, other existing tools within the company for 

interoperability and integration, etc. Specific modeling capabilities, such as surface modeling 

or assembly modeling, may have to be checked for the company’s particular needs. 

Historically, CAD tools began to be available on mainframe computers and workstations, and 

these tools eventually evolved into CAD/CAM/CAE tools with a variety of add-on modules. 

CMU/SEI-2003-TR-013 33 
Representative “full-featured” mechanical CAD tools include Pro/Engineer 

(http://www.ptc.com/), CATIA (http://www.catia.com/), IDEAS (http://www.plmsoleds.com/) and Unigraphics NX (http://www.plmsolutions-eds.com/). As personal computers 

(PCs) become more powerful, PC-based low-cost CAD tools with more limited capabilities 

appeared in the market. In fact, today the border between the full-strength CAD tools and the 

PC-based “light-duty” CAD tools becomes obscure, in that PC-based CAD tools have 

gradually been providing increasingly more sophisticated capabilities and add-ons. “Lightduty” CAD tools include SolidWorks (http://www.solidworks.com/), Solid Edge 

(http://www.plmsolutions-eds.com/), Autocad Inventor (http://www.autodesk.com/), 

IronCAD (http://www.ironcad.com), think3 (http://www.think3.com), Cadkey

(http://www.cadkey.com), Microstation (http://www.bentley.com), and Visual CAD 

(http://www.visualcad.com). A comprehensive evaluation of the above CAD tools, along with 

several others, can be found in the CAD Rating Guide by B. Holtz and available from

http://www.cyonresearch.com. Other useful sites for discussion and evaluation of CAD tools 

are http://www.eareport.com, http://www.upfrontezine.com, and http://www.tenlinks.com. 

5.3 Multidisciplinary Analysis and Optimization 

Engineering analysis and optimization techniques are evolving from single or uncoupled 

problem solving in single domains to multi-disciplinary or coupled problem solving. In this 

section, examples of commercial analysis tools that can model and solve single-domain and 

coupled multiphysics problems are reviewed. A structural optimization tool as an example of 

optimization software and two multidisciplinary engineering optimization environments are 

also introduced. 

5.3.1 Engineering Analysis and Simulation Tools

The most popular and frequently used CAE analysis tools are FEA tools for structural, 

thermal, and fluid flow analysis. The major CAE software vendors provide FEA modules 

with convenient user interfaces to CAD models. Frequently, the core analysis modules are 

licensed from vendors specializing in analysis software and interfaced with CAD systems. 

Two popular general purpose FEA tools are Ansys (http://www.ansys.com/) and Nastran 

(http://www.mscsoftware.com/).

Some of the more specific analysis needs and representative corresponding specialized 

analysis tools are non-linear analysis (Marc, http://www.mark.com/, LS-DYNA, 

http://www.ls-dyna.com/); mold flow analysis (Moldflow, http://www.moldflow.com/); metal 

forming analysis (DEFORM, http://www.deform.com/); casting analysis (MAGMA, 

http://www.magmasoft.com/); and fluid dynamics analysis (FLUENT,

http://www.fluent.com/). 

34 CMU/SEI-2003-TR-013 
Dynamic mechanical system simulation and analysis tools are also commercially available 

with varying degrees of specialization. ADAMS 

(http://www.mscsoftware.com/products/products_detail.cfm?PI=413), Pro/ENGINEER 

Mechanism Dynamics (http://www.ptc.com/), and DADS (http://www.lmsintl.com/) are 

representative examples of such products. 

In order to bridge the gap between CAD and CAE activities in the product development 

process, CAE tools for preliminary and simplified analysis embedded in CAD systems have 

recently emerged. Examples in this category are DesignSpace (http://www.ansys.com/), 

VisualNastran (http://www.mscsoftware.com/), CATIA Generative Part Stress Analysis 

(http://www.catia.com/) and Unigraphics Strength Wizard 

(http://www.eds.com/products/plm/). The goal of these products is to provide the capability

of early assessment of the behavior of the design, before going into elaborate detailed design. 

Since these tools are to be used by designers, not analysis specialists, the user interfaces are 

designed to be simple and easy to use. After the preliminary analyses are completed, the 

models generated for analysis may be further used in detailed CAD operations. 

5.3.2 Multiphysics Modeling and Analysis 

Multiphysics modeling is important, since real-world mechanical behavior is often the result 

of not one, but several, physical factors acting simultaneously. A chemical reaction, for 

instance, cannot take place without mass and heat transfer also occurring. FEMLAB 

(http://www.femlab.com/), based on MATLAB (http://www.mathworks.com/), is a simulation 

tool that can arbitrarily couple any number of nonlinear physical processes into a single 

model and solve them simultaneously. This analysis tool solves a system of partial 

differential equations simultaneously, rather than sequentially, to improve convergence. This

implies that analysts can model and simulate their applications as close to reality as possible 

and necessary for the problem at hand. Similarly, Professional Multiphysics 

(http://www.algor.com/) and ANSYS/Multiphysics (http://www.ansys.com/) enable engineers 

from multiple disciplines to couple the effects of different types of physical behavior and 

study their impact on a design, thus performing more realistic simulations.

5.3.3 Optimization 

Every effort in product development in a manufacturing enterprise is targeted, informally at 

least, towards optimizing some design feature or manufacturing process. More formal 

optimization approaches are available to enhance the efficiency and effectiveness of the 

optimization process. A broad range of tools is available focused on different aspects of 

optimization, including shape, geometry, and topology optimization of a machine part or 

structure, mechanical system optimization, and distributed multidisciplinary optimization. 

CMU/SEI-2003-TR-013 35 
Altair OptiStruct (http://www.altair.com/) is one of the finite element based structural 

analysis and optimization tools for conceptual design and design refinement. Its capabilities 

for topology, shape, and size optimization can be used to design and optimize structures to 

reduce weight and tune performance. 

ADAMS (http://www.adams.com/) provides suites of mechanical system simulation tools for 

specialized application domains, including the automotive, aerospace, machinery, and railcar 

industries. The capabilities include modeling of mechanical systems, mathematical and 

visual simulation, and optimization for user-defined optimization criteria. 

NuEngineer (http://www.numan.com/) allows engineers to design, analyze and optimize 

designs with artificial intelligence techniques, across engineering applications with different 

tools. The software provides integration tools for CAD and analysis tools. The software 

enables engineers to automatically search through many new designs across different 

engineering applications and platforms with intelligent search criteria. 

iSIGHT (http://www.engineous.com/engineous.html) is an optimization tool that integrates 

analysis tools and enables design explorations. It automates iterative analysis with numerical 

optimization, exploratory search, and expert system approaches. It also provides quality

engineering tools such as Monte Carlo analysis, reliability-based design and optimization, 

and the Taguchi method for robust design. 

A summary of the COTS tools presented in Sections 5.2 through 5.3.3 is shown in Table 3. 

Table 3: Sample of COTS CAD and CAE Tools 

Tool Supplier Function 

Pro/Engineer PTC High-end CAD

CATIA Dassault Systemes High-end CAD 

IDEAS Electronic Data Systems High-end CAD 

Unigraphics Electronic Data Systems High-end CAD 

SolidWorks SolidWorks Corp. Midrange CAD

Solid Edge Electronic Data Systems Midrange CAD 

Autocad Inventor AutoDesk Inc. Midrange CAD 

Ansys ANSYS, Inc. Full-featured FEA 

Nastran MSC Software Corp. Full-featured FEA 

Marc MSC Software Corp. Nonlinear FEA 

LS-DYNA Livermore Software

Technology Corporation 

Nonlinear FEA 

Moldflow Moldflow Corp. FEA for injection molding 

DEFORM Scientific Forming

Technologies Corp. 

FEA for metal forming 

36 CMU/SEI-2003-TR-013 
MAGMA MAGMA Foundry

Technologies, Inc. 

FEA for casting 

CMU/SEI-2003-TR-013 37 
FLUENT Fluent Inc. FEA for fluid dynamics 

ADAMS MSC Software Corp. Dynamic mechanical 

simulation and analysis 

Pro/ENGINEER 

Mechanism

Dynamics 

PTC Dynamic mechanical

simulation and analysis 

DADS LMS International Dynamic mechanical

simulation and analysis 

DesignSpace ANSYS, Inc. Entry-level FEA

VisualNastran MSC Software Corp. Entry-level FEA 

CATIA Generative 

Part Stress 

Analysis 

Dassault Systemes Entry-level FEA 

Unigraphics 

Strength Wizard 

Electronic Data Systems Entry-level FEA 

FEMLAB COMSOL, Inc. Multiphysics FEA 

MATLAB The MathWorks Environment for data 

analysis, visualization, and 

application development 

Professional 

Multiphysics 

Algor, Inc. Multiphysics FEA 

ANSYS/ 

Multiphysics 

ANSYS, Inc. Multiphysics FEA 

OptiStruct Altair Engineering, Inc. Structural FEA and 

optimization

NuEngineer Numan Intelligence, Inc Integrating/optimizing

environment for CAD and 

CAE tools 

iSIGHT Engineous Software, Inc Integrating/optimizing 

environment for CAD and 

CAE tools 

5.4 Interoperability of Tools, Data, and Models 

Interoperability of tools, data, and models becomes increasingly important for the close 

integration of engineering processes in an extended enterprise. CAD must communicate with

CAE to facilitate the engineering analysis needed in the design process. CAD must 

communicate with CAM to provide the smooth transition from design to manufacturing. 

CAM must communicate with numerically controlled (NC) machine tools to execute the 

manufacturing activities. CAD must communicate with PDM to ensure proper product 

configuration control. Communication protocols such as IGES (Initial Graphics Exchange 

Specification) (www.nist.gov/iges/), STEP (STandard for the Exchange of Product model 

data) [ISO 94], and various OMG (Object Management Group) standards have been created 

to facilitate this inter-tool communication. In this section, current solutions and near-future 

38 CMU/SEI-2003-TR-013 
plans to address interoperability issues in engineering environments are discussed. Various 

data interchange paths, depicted in Figure 10, are addressed below in detail, with examples of 

available commercial tools and protocols. 

IGES, STEP, Direct translation of 3D shape 

Direct translation with features and history data

OMG CAD Services

OMG PDM Enablers 

STEP extension for parametric model 

Embedded system

PDM

Other 

Applications

(Incl. CAx)

CAE

CAD 

CAM

CAD 

CAD

PDM 

STEP AP209

STEP PDM

STEP-NC

NC

Figure 10: Data Interchange Map Between Application Areas 

5.4.1 CAD-CAD Interoperability

Computer technology began to penetrate into product development and manufacturing 

processes with the emergence of CAM technology in the 1950s. However, it was only after 

the 1970s that computer use became popular in product design under the name of CAD. 

CAD technology had been supporting the development of the product’s shape description 

with two-dimensional drafting and three-dimensional modeling capabilities until featurebased parametric design technology emerged in the mid 1980s. The major motivations for 

using CAD were digital archiving, ease of reuse, and potential linkage to CAM. Tighter 

integration of CAD with downstream applications, such as CAM and CAE, came later. Even 

before the advent of three-dimensional parametric design technology, there existed several 

different commercial CAD products and in-house software developed by manufacturing 

enterprises. Users of CAD products began to realize that the data created with one system

was not interchangeable with other systems and their internally developed databases. An 

effort to create a standard for the exchange of CAD data began in 1979; this standard later 

became IGES. The fundamental idea of IGES was to transfer two-dimensional drawing data, 

later including three-dimensional shape data, in fixed file format, with an electronic form. 

CMU/SEI-2003-TR-013 39 
Although IGES served its purpose of exchanging CAD data between different CAD systems, 

limitations of the standard were observed. The major deficiencies were large file sizes, long 

processing times, lack of upward compatibility due to the fixed file format and, most 

importantly, the restriction of information exchange only to shape data rather than covering 

complete product data. Despite these limitations, IGES is being supported by most CAD 

products and is still widely used for CAD data exchange. 

In the meantime, the idea of utilizing a geometric modeling kernel for developing CAD 

products emerged in 1987. The first commercial modeling kernel, ACIS, appeared in 1990. 

Later, similar kernels, such as Parasolid, Designbase, and Open CASCADE, became 

available as products. It was contemplated that the interoperability problem of exchanging 

three-dimensional shape data might be solved if one of the kernels were widely adopted for 

CAD product development. However, this never happened, for several obvious reasons. 

Major CAD vendors did not want to give up their own proprietary modeling kernels due to 

both technical reasons and company policies. Even if one modeling kernel had been widely

adopted at the time, the interoperability problem would have not been solved because of the 

new modeling paradigm, with feature-based, parametric, and history-based modeling, which 

began to appear in the mid 1980s. However, three-dimensional solid shape data exchange 

with a kernel-based data format, such as the ‘.sat’ files from ACIS, is also currently supported 

and used between CAD products that utilize the same modeling kernel. 

After the shortcomings of the IGES had been observed, a new standardization effort for the 

representation of product model data began in 1984. This new standard was based on 

existing standards and was targeted to provide a mechanism for the exchange of lifecycle 

product model data in computer interpretable electronic form. The resulting international 

standard, ISO 10303, was informally named STEP [ISO 94]. One of the significant 

departures from existing standards was that a formal information modeling technology was 

adopted to represent data in the standard, instead of using fixed file formats. Another 

ambitious goal was the idea of sharing product data between various departments and 

organizations beyond simple data exchange. In 1994, the first STEP standard at the 

application level, AP 203 Configuration Controlled 3D Designs of Mechanical Parts and 

Assemblies, was approved by ISO [ISO 94]. Fourteen application protocols (APs) have been 

approved as international standards at the time of writing this report. Among these, AP 203 is 

still the most widely supported standard in commercial products and is used extensively. 

PDES Inc., an international industry/government consortium devoted to accelerating the 

development and implementation of STEP, examines commercial products for STEP

translation capabilities and reports the results periodically

(http://pdesinc.aticorp.org/vendor.html). Also, US PRO, a nonprofit membership 

organization established by industry, began STEP certification in 1998 

(http://www.uspro.org/). STEP-certified products are those that have successfully completed 

a syntacticevaluation of the product’s adherence to the STEP standard in accordance with the 

testing procedures and guidelines that form a part of the standard. 

40 CMU/SEI-2003-TR-013 
Although STEP AP 203 is widely supported in commercial products, it exhibits serious 

deficiencies in handling feature-based parametric product model data. The new modeling 

paradigm, namely feature-based parametric modeling, came into the market in the mid 1980s, 

and the technology has been adopted by most major CAD/CAM vendors since then. 

However, STEP AP 203 was designed toward the conventional static three-dimensional shape 

representation with configuration data. Currently there is no agreed-upon standard to 

represent feature-based parametric product data, except STEP AP 214 [ISO 214:01] and AP

224 [ISO 224:01], in which there are limited feature-based representation schemes for 

machining purposes. However, several research activities are in progress to address the 

interoperability of CAD models with parametric capability [Pratt 01].

In response to the urgent need of solving parametric CAD data interchange problems, 

companies have recently begun to provide translators for exchanging product data, including 

feature, history, and constraint information, with their own proprietary technology. 

Proficiency (http://www.proficiency.com/) and TTI (http://www.translationtech.com/) 

provide similar functionalities for exchanging native feature and history data between four 

major CAD products: CATIA, Unigraphics, Pro/Engineer, and SDRC IDEAS. However,

their business models differ. Proficiency markets its translating software as an enterprise 

solution, while TTI provides pay-per-use translation service as an ASP, as discussed below. 

Theorem Solutions (http://www.theorem-usa.com/) and ITI (http://www.DEXCenter.com/) 

also provide software and pay-per-use services for direct translation between major CAD 

tools and standard-based translation. InterOp (http://www.spatial.com/) is a standalone 

translator with the same translation capability.

5.4.2 Accommodation of Legacy CAD Data

3D CAD-translated data from other systems or static solid model data in legacy databases are 

hard to edit and utilize further within modern parametric feature-based systems. Some CAD 

tools offer feature recognizer modules for building their own native parametric feature-based 

data automatically from static 3D data. The data generated this way may not represent 

exactly the designer’s intention or modeling process, but it will at least allow easier 

modification of the model later. SolidWorks (http://www.solidworks.com/index.html) and 

Solid Edge (http://www.solid-edge.com/) provide feature recognition modules for this 

purpose. 

5.4.3 CAE-CAE Interoperability

Data interchange problems between CAE systems have not been seriously addressed until 

recently. Various analysis systems had their own proprietary interfaces and internal 

representations for preparing analysis models and representing analysis results. Occasionally, 

input data formats of the more popular analysis software have been supported by other 

systems for interoperability. However, design and collaboration on a product model in an 

CMU/SEI-2003-TR-013 41 
extended enterprise of many companies necessitated a standard for describing the analysis 

data (http://pdesinc.aticorp.org/pilots/engineering.html). STEP AP 209 provides a neutral 

data format representation of analysis models needed to conduct engineering analyses within 

an iterative design-analysis environment using heterogeneous analysis tools [ISO 209:01]. 

STEP AP 209 enables version control of design and analysis information linked to a product 

structure; it is thus a powerful CAD/CAE interoperability aid as well. STEP AP 209 was 

approved as an international standard in 2001, and it is expected to be widely supported by

analysis systems.

5.4.4 PDM-PDM Interoperability

Collaboration on product data in an extended enterprise of many companies also necessitated 

a standard for describing product data within PDM systems. Although the work is still in 

progress, the ISO 10303 STEP PDM Schema provides a reference information model for the 

exchange of a central, common subset of the data being managed within PDM systems. It 

represents the intersection of requirements and data structures from a range of STEP

application protocols, all generally within the domains of design and development of discrete 

electro/mechanical parts and assemblies. Although the STEP PDM Schema is still under 

development, several PDM systems currently support it. 

In an alternative approach, the OMG PDM Enablers is intended to provide access to the 

services of product data management systems from various application software systems in a 

manufacturing enterprise (ftp://ftp.omg.org/pub/docs/mfg/99-10-04.pdf). Activities 

supported by such “client” applications encompass product conception and planning, product 

design, manufacturing engineering, production, delivery, and maintenance. The emphasis is 

on providing interfaces for the management of product data. 

5.4.5 CAD-CAE Interoperability

Some system analysis tools, such as kinematic and dynamic analysis software, have their 

own modeling interfaces, not compatible with other systems. However, most FEA analysis 

tools offer capabilities for importing 3D shape data from CAD systems. Major vendors of 

CAD systems offer FEA modules “integrated” with CAD tools, even though the integration 

means only a convenient user interface and the smooth transfer of 3D shape data from the 

CAD module to the FEA module. Most of the independent FEA tools compatible with CAD 

systems provide data interface modules for major native CAD data formats and for standard 

formats such as IGES and STEP. STEP AP 209, discussed above, provides explicit linkages 

between the shape data in the design (i.e., CAD) and analysis models. 

However, successful data import from a CAD module to an FEA module does not guarantee 

a successful analysis. There are two categories of practical problems that impede the smooth 

integration of CAD and analysis tools. The first category is related to improper geometry

data that is not suitable for processing in the analysis, mainly due to erroneous practices of

42 CMU/SEI-2003-TR-013 
CAD operators and to problems resulting from data translation. This kind of problem can be 

solved by properly training CAD operators and by using geometry healing tools such as 

GeometryQA

(http://www.cadfem.de/knowledge_engineering/pqa/geometryqa_download.pdf), CAD/IQ 

and CADfix (http://www.transcendata.com/products_cadfix.htm).

The second category is related to the fact that the models needed for analysis are usually

different from the detailed 3D design model. Very often, a significant amount of time is 

consumed in idealization or remodeling for analysis after the detailed 3D design is finished. 

This effort can be reduced by the feature suppression capabilities of some CAD tools and/or 

supplementary modeling tools such as mid-plane extraction tools for mold flow analysis. 

The feature suppression capability may be very efficient when the CAD operator or designer 

has some knowledge of the needs of the downstream analysis activities, since successful 

feature suppression operations heavily depend on how the model is created. On the other 

hand, technologies for automatic or even semi-automatic idealization from detailed 3D 

shapes to analysis models, which may involve multiple levels of abstraction for various 

domain-specific analyses, are not yet commercially available, except for mid-plane 

generation from thin 3D solid models for mold flow analysis. 

5.4.6 CAD-CAM Interoperability

Data interchange between CAD and CAM tools has not been a serious issue in the past, 

because CAM tools operate only on the final detailed geometry. Most of the problems 

encountered during numerical control code generation are related to geometry details such as 

surface discontinuities due to different tolerances between CAD and CAM tools, and cracks,

sliver surfaces, duplicate surfaces, reversed surfaces, etc., due to CAD operators’ poor 

practices. These problems can be solved by properly training CAD operators and by using 

geometry analysis or fix/healing tools. Current CAM tools provide data interface for IGES,

STEP and major native CAD formats and generate ISO 6983 G-code for NC controllers. A

new initiative, STEP-NC [STEPNCRef], is being carried out in the STEP community to 

develop a standard for more streamlined and intelligent interfaces between CAD and CAM, 

which will eventually make ISO 6983 obsolete. With the new standard, future NC controllers 

will operate on 3D shape data and high-level machining operations instead of direct 

commands for motion control in machine tools 

(http://www.steptools.com/library/stepnc/index.html).

5.4.7 CAD-PDM Interoperability

It is not necessary for the typical SME to implement a full-scale PDM system for product 

data management. Implementation of full-scale data management solutions requires a 

substantial investment in time and money for planning, setup, and deployment. However,

some PC-based CAD tool vendors have begun to include essential components of PDM 

capabilities in their CAD tools (http://www.solid-edge.com/insight/default.htm, 

CMU/SEI-2003-TR-013 43 
http://www.think3.com/products/). Capabilities of these tools include data vaulting, revision 

management, engineering change order processing and bill of materials (BOM) management 

so as to help companies capture, share, and reuse the collective knowledge of their design 

engineering organizations. Although this built-in PDM capability may not fit perfectly every

company’s needs and may not be easily customized, it is worth investigating during any CAD 

tool selection process. 

The interoperability protocols discussed in Sections 5.4.1 through 5.4.7 are summarized in 

Table 4. 

Table 4: Interoperability of AEE Tools 

CAD CAE CAM PDM

CAD STEP AP203 STEP AP209 STEP NC 

CAE STEP AP209 STEP AP209 

CAM STEP NC

PDM STEP PDM

5.5 System Analysis and Synthesis 

5.5.1 Design Methodology Tools 

Traditionally, the design process has been considered an iterative process of applying art, 

experience, and science by designers. Although this is largely true, more systematic design 

approaches can be applied in order to reduce iterations and to generate better designs from

design concepts. These methods are particularly useful in the integrated design-analysis, 

function-driven design, and multifunctional design-analysis usage scenarios of Section 2.5, 

which feature early analysis-driven design iterations.

Axiomatic design is one such design methodology. Axiomatic design theory is based on the 

notion that axioms, or universally accepted principles, can be used as the foundation for good 

design. Acclaro (http://www.axiomaticdesign.com/) helps designers make better design 

decisions, based on a fundamental set of principles that determine good design practices. The 

fact that the axiomatic design methodology is based on a fundamental set of design principles 

that operate in multiple domains differentiates its applicability from that of knowledge-based

design support systems that are closely tied to their application domain. 

44 CMU/SEI-2003-TR-013 
TRIZ (Theory of Inventive Problem Solving) is based on information extracted from patents, 

and provides analytical and knowledge-based tools that serve as a systematic path to 

innovation. Innovation WorkBench and its companion tools (http://www.ideationtriz.com/) 

based on TRIZ can be used to solve innovative problems in design and engineering. 

Quality Function Deployment (QFD) is a systematic process for motivating a business to 

focus on its customers. It is used by cross-functional teams to identify and resolve issues 

involved in developing products for customer satisfaction. Tools based on the QFD 

approach, such as QFD/CAPTURE (http://qfdcapture.com/), can be used in product design to 

provide a customer-oriented point of view. 

Design of Experiments (DOE), using the Taguchi approach, attempts to improve product 

quality, defined as consistency of performance. The prime motivation behind the Taguchi 

experiment design technique is to achieve reduced variation, hence producing robust designs. 

Qualitek-4 (http://www.rkroy.com/wp-q4w.html) and iSIGHT

(http://www.engineous.com/engineous.html) are examples of tools that support robust design 

processes with the Taguchi approach. 

5.5.2 Knowledge-Based Design Support Systems 

CAD systems are basically shape defining tools, while important design decisions are made 

by designers reasoning about function, using their expertise, experience, and supporting

tools, such as analysis tools, in their particular domain. The concept of knowledge-based 

design is to capture domain-specific design rules in design support systems, whether these 

rules are represented in mathematical form or in rule-based form, and to help non-expert 

designers to make better design decisions. This technology is supported in the commercial 

market in two ways. One is the so-called “knowledgeware” that provides easily customizable 

tools to represent or supply links to a knowledge base of experts and such information as 

product rules, performance data, and legislative and safety codes, and to provide interfaces to 

CAD models. ICAD from Knowledge Technologies International 

(http://www.ktiworld.com/our_products/icad.shtml), and AML (http://www.technosoft.com/) 

belong to this category of products. More general design environments, not restricted to 

specific application areas, can be built using Catia Generative Knowledge 2 

(http://www.catia.com/) and Unigraphics NX 

(http://www.eds.com/products/plm/unigraphics_nx/ ). 

Another approach is the “design wizard” available as a design support tool tightly linked to a 

specific CAD system. In this case, the design support system is already implemented 

towards a specific application domain such as mold design, sheet metal part design, or piping 

design. SolidWorks Piping (http://www.solidworks.com/), CATIA Sheetmetal Design 

(http://www.catia.com/), Unigraphics Mold Wizard (http://www.eds.com/products/plm/), and 

I-DEAS Harness Design (http://www.plmsol-eds.com/) are examples of such products. 

CMU/SEI-2003-TR-013 45 
5.5.3 Tools for System Analysis 

Matlab (http://www.mathworks.com/) is a tool for technical computation, modeling, analysis, 

and visualization. It can be customized for specific engineering applications such as 

automotive and aerospace engineering. It allows quick system analysis of specific problems 

for which an off-the-shelf tool is not readily available. Many third party application tools 

built on top of Matlab are available in various application areas. Another tool which offers 

capabilities for general scientific computing is Mathematics (http://www.wolfram.com/ ). 

5.6 Collaborative, Distributed Systems 

With the development of software integration technologies over the network, many

engineering systems are finding their way into collaborative distributed systems for 

efficiency and improved productivity. PDM systems, product design systems, CAD systems, 

and analysis systems are among systems that exploit the advantages of collaborative and 

distributed systems concepts. Although many software products claim that they support

collaborative engineering, the most practical, affordable, and widely accepted products for 

collaboration for now are 3D data viewers over the network, described below.

5.6.1 Support for Visual Collaboration 

CAD data viewers are used for visual collaboration on product data between manufacturing 

enterprises and their supply chains. With these viewers, people around the world can work 

together on the same visual data, simultaneously and in real time, across organizational and 

technological boundaries. This software is also useful when multiple CAD systems are used 

throughout the organizations, because viewers support multiple CAD formats for

visualization. Viewers allow every authorized member in the organization to deal with 

heterogeneity, visualizing designs from a variety of formats without running CAD software. 

Viewers enable design review meetings over the Internet by allowing project members to 

view and analyze a model concurrently while shifting control between members. Common 

functionalities other than visualization over the network include markup, geometric 

measurement, extraction of inertial properties, and generation of cut views. Popular products 

in this category include e-VIS (http://www.e-vis.com/), 3DView (http://www.actify.com/), 

Cimatron QuickConcept (http://www.cimatron.com/), and AutoVue 

(http://www.cimmetry.com/). 

5.6.2 Support for Collaborative Product Definition 

Collaboration for product development in a distributed environment goes beyond just visual 

collaboration in design meetings between remote parties. Engineers must be linked up with

their colleagues over the Internet and develop products together. In this way design 

challenges can be identified and solved without delays and misunderstandings. 

46 CMU/SEI-2003-TR-013 
One of the products with such an idea is OneSpace (http://www.cocreate.com/). OneSpace 

products, with a built-in CAD tool at the core, enable design teams to capture real-time input 

from an extended design team. The user interface allows engineers to discuss and 

collaboratively improve the design together with manufacturers, external development 

partners, and colleagues in other disciplines. OneSpace products also enable designers to 

further develop and enhance the parts and assemblies created by others by treating imported 

designs like native designs. This capability is useful because designers often need to share 

ideas and expertise, even when they are working with separate models on different CAD 

systems. For efficient collaboration, OneSpace provides modules to manage access rights, 

data, and projects in a way that encourages close collaboration while protecting each 

company’s intellectual property.

Alibre Design (http://www.alibre.com/) takes a different approach to accomplish 

collaboration in product design and real-time team modeling. It provides CAD modeling and 

data repository capabilities through the Web-based server. Engineers need only minimal 

client interface software to access interactive and collaborative 3D design service and data 

management service at the server. The Web-based service bureau mechanism allows 

members of the extended enterprise and all tiers of the supply chain to share data and 

collaborate in real time. The low-cost standard hardware requirements and the ease of 

deployment of this approach could be beneficial to SMEs. However, data security is one of 

the major concerns. 

Recently, several vendors have focused on Product Lifecycle Management (PLM) 

frameworks, which support collaborative design activities throughout the product lifecycle. 

The PLM market is currently dominated by EDS’ Teamcenter 

(http://www.eds.com/products/plm/teamcenter/), PTC’s Windchill (http://www.ptc.com), 

MatrixOne’s Matrix10 (http://www.matrixone.com/), and IBM/Dassoult’s Smarteam/Enovia 

(http://www-1.ibm.com/solutions/plm/), with other players such as Alventive 

(http://www.alventive.com) providing support for real time 3D collaboration, project data 

space, and project tracking. In addition, companies such as Toyota Motor Corporation are 

commercializing software developed for addressing in-house needs (see 

http://www.xxen.net/e-home/). An analysis of these and other PLM frameworks can be found 

in reports from Gartner (http://www.gartner.com), DH Brown Associates Inc. 

(http://www.dhbrown.com), Daratech (http://www.daratech.com) and CIMdata 

(http://www.cimdata.com). 

5.6.3 OMG CAD Services 

While most of the standard activities related to product design are focused on the 

representation of product data, the OMG has initiated a standard called CAD Services for 

high-level functional and operational interfaces for mechanical CAD systems 

(http://www.omg.org/homepages/mfg/mfgppe.htm). The aim of this standard is to provide 

CMU/SEI-2003-TR-013 47 
users of design and engineering systems the ability to seamlessly integrate best-in-class 

software across a wide variety of CAD/CAM/CAE tools through Common Object Request 

Broker Architecture (CORBA) interfaces. These standard interfaces make possible a 

distributed product design environment that includes a variety of CAD systems. The intent is 

to expose the existing CAD functionality through high-level functional and operational 

interfaces. These interfaces are to complement existing standards such as STEP. This 

activity is currently under progress and is supported by 12 organizations including software 

vendors such as Dassault Systems, Spatial Technologies, and Theorem Solutions. 

5.7 Virtual Environments, Immersive CAD, and 

Simulation Systems 

The immersive environment is an extension of virtual reality. In this environment, the user is 

an active participant in the virtual scene. A display unit mounted in the user’s headset 

projects a virtual view that moves as the user’s head is moved. The user wears an

instrumented glove, the image of which moves in the virtual view as the user’s hand is 

moved. In some immersive systems the glove provides pressure feedback to the user as 

she/he “grabs” an object in the virtual view. 

There are numerous engineering design applications of immersive environments. 

Automobile, truck, and other equipment operators are doing extensive ergonometric studies 

to design and analyze their equipment for human comfort and efficiency. Similarly,

simulations of manufacturing operations, such as manual part assembly, are performed in 

immersive environments. Increasingly, immersive environments are beginning to augment, if 

not replace, physical simulators such as flight and driving simulators. 

An “inverted” immersive environment arises when the projected computer output is 

superimposed on the user’s view of the real world through the use of a wearable computer 

with a head-mounted display. Practical engineering applications of wearable computers 

abound, particularly in the maintenance and inspection of complex systems that are difficult 

or dangerous to reach. The maintenance worker or inspector has both hands free, and with 

simple commands can call up relevant parts of the design model, operating or maintenance 

instructions, or previous inspection reports she/he needs to perform the work required. 

One application area of graphical virtual reality (VR) technology, combined with discrete 

simulation technology, has been for simulating and optimizing manufacturing systems in the 

early stages of factory design. Manufacturing system simulation tools are used for 

determining the optimal equipment configuration and layout, troubleshooting an existing 

system, including identifying bottlenecks in the operation, and testing equipment controls 

prior to installation. The simulation can also predict problems related to material flow and 

working conditions of human operators in the workplace. 

48 CMU/SEI-2003-TR-013 
Usually, factory layout and design modules provide a user-definable component library of 

shop floor and assembly equipment, as well as related information such as dimensions and 

possibly cost. The planner designs a layout by browsing through the library, selecting desired 

equipment and positioning it in the 3D-workplace layout. Some simulation tools allow the 

planner to analyze line throughput while taking into account different product mixes, 

variants, and production volumes. Human models are also provided to allow the planner to 

design a manual workplace that is optimized for assembly time, reachability, fields of view, 

and detailed hand motions for assembly. 

Representative tools for virtual factory simulation include the AutoMod suite of simulation 

software (http://www.autosim.com/), a suite of simulation products for factory simulation, 

robotics, and machining from Delmia (http://www.delmia.com/), products including eMWorkplace from Technomatix Technologies Ltd. (http://www.tecnomatix.com/), and factory

modeling and layout analysis products from EDS (http://www.eds.com/products/plm/). 

5.8 Engineering ASP on the Web 

An environment component not considered by the NRC report but of considerable potential 

interest to SMEs is the concept of application service providers (ASPs). ASP is a new type of

business model that provides various application services on a pay-per-use basis on the 

Internet. ASP for engineering tasks came later than in other application domains such as 

business transactions. The complex nature of engineering data and activities, including the 

handing of complex structures of product data and 3D shape data, is a challenge to the ASP

concept in the engineering domain. However, in some engineering areas related to product 

development processes, the ASP concept is well accepted and several service providers are 

active in the market. Several of these are discussed below.

5.8.1 CAD Data Translation 

This is probably the most widely accepted ASP application related to product development 

processes. There are two reasons that justify wide acceptance of CAD data translation 

through ASPs. One reason is that CAD data translation is not an everyday engineering 

activity. Furthermore, there are many combinations of source and destination pairs for 

translation, of which a few pairs are occasionally used. Therefore, with ASPs there is no 

need to purchase expensive software and maintain the software to catch up the version 

changes of data formats of commercial tools and standards. The second reason is that, unlike 

other interactive engineering activities, input data for translation requests is simple and the 

output is a single file. As described previously, translation services are available between and 

across standard formats, kernel-based formats, and native CAD system formats with optional 

feature-based parametric data. 

CMU/SEI-2003-TR-013 49 
STEP Tools, Inc. (http://www.steptools.com/) offers free STEP translation service and 

markets standalone STEP translators for Parasolid and ACIS solid models. ITI 

(http://www.DEXCenter.com/) offers CAD translation service for IGES, STEP, and STL

formats and four major commercial CAD formats, along with CAD data repair and “healing” 

service. TTI (http://www.translationtech.com/) provides pay-per-use translation services for 

feature-based parametric data between four major CAD systems. Theorem Solutions 

(http://www.theorem-usa.com/) also provides direct translation services between major CAD 

tools and standard-based translation services. 

5.8.2 Engineering Analysis 

FEA is another area of engineering application potentially well suited for the ASP model. It 

is computation intensive and requires little interaction during the actual computation, if the 

analysis model is well formulated in advance. Analysis with ASP is not appropriate for 

simple preliminary analyses that require rapid response time during frequent design 

modification and analysis iterations; in this case the computations are not likely to be 

intensive. However, ASP analysis will be cost-efficient for the occasional detailed analyses 

with complex models that require considerable computational resources. By using ASP

analysis services, SMEs with occasional demands for computation-intensive analyses can 

avoid the costly investment for software and high performance hardware and maintenance 

costs for upgrades. 

The e-compute service from Altair (http://www.altair.com/) requires its pre-processing 

module to be installed on the client computer. The server is connected through the client preprocessing module, and the analysis job is sent to the server. Then the server carries out the 

computations and generates analysis reports. The simulation center by MSC software 

(http://simulate.engineering-e.com/) does not require any client code installed on the local 

computer. Several analysis tools, including a CAD tool, are available through a graphical 

interface that looks like the standalone analysis tool to the user. The e-CAE from ANSYS 

(http://www.ansys.com/ecae/) provides similar service by receiving analysis models through 

the Internet. Web4Engineers’ (http://www.web4engineers.com/) site provides various 

engineering tools including CAD, CAE, and CAD viewers through the Web. 

5.8.3 CAD and Data Repository 

As mentioned above, some companies offer usage of CAD tools through the Web interface. 

Alibre Design (http://www.alibre.com/) offers CAD modeling and data repository capabilities 

through the server. Engineers need only minimal client interface software to access 

interactive and collaborative 3D design and data management services at the server. 

Web4Engineers (http://www.web4engineers.com/) offers 2D CAD tools through the Web. 

The simulation center at MSC Software (http://www.mscsoftware.com/) offers IronCAD 

through a Web interface. 

50 CMU/SEI-2003-TR-013 
5.8.4 Parts Catalog Services 

The availability of electronic 3D part catalogs can reduce the total time required for product 

design. This technology can also be used for quick configuration of design variations with 

detailed geometries. For the supplier, supplying a standard parts catalog with 3D data means 

tighter engineering integration with the customers. With this technology, suppliers can 

interact with their customers at the early stages of product design with engineering details. 

The PartLib Web site (http://www.partlib.com/) offers a free repository for CAD parts, 

libraries, and catalogs. PARTsolutions (http://www.part-solutions.com/) offers both a part 

catalog server and tools for viewing, publishing, and catalog searching. 

5.9 Summary 

Technology trends and representative product examples of common COTS elements for AEE 

components for SMEs have been presented in this report. The AEE components and 

characteristics from the NRC AEE Phase 1 report have been expanded into more detailed 

levels so as to be able to relate AEE elements to their corresponding commercial products. It 

is to be emphasized again that the lists of COTS products presented are intended to be 

illustrative rather than exhaustive, and that the range of COTS elements is expected to 

continue to grow in the future. Another trend discernible from the descriptions is the 

increasingly tighter integration or “bundling” of vendors’ products and services, to the point 

where specialized “mini-AEEs” may soon become available as COTS. 

The components described in this report cover a wide range of characteristics necessary to 

implement AEEs. A single SME does not need to implement all of these components, but 

needs to carefully identify the components necessary for its specific needs, the planned 

interactions between them, and the range of COTS products implementing the needed 

components. A carefully prepared plan will lead to successful expansion of the AEE with 

additional components in the future. 

CMU/SEI-2003-TR-013 51 
References 

[Brownsword 00] Brownsword, L. & Place, P. Lessons Learned Applying Commercial 

Off-the-Shelf Products: Manufacturing Resource Planning II 

Program (CMU/SEI-99-TN-015, ADA379746). Pittsburgh, PA: 

Software Engineering Institute, Carnegie Mellon University, June 

2000. 

[Carney 98] Carney, David J. Quotations from Chairman David - A Little Red 

Book of Truths to Enlighten and Guide on the Long March Toward

the COTS Revolution. Pittsburgh, PA: Software Engineering 

Institute, Carnegie Mellon University, 1998. 

[Fenves 90] Fenves, S. J.; Flemming, U.; Hendrickson, C.; Maher, M. L.; & 

Schmitt, G. “Integrated Software Environment for Building Design 

and Construction.” Computer-Aided Design 22, 1 (1990): 27-36. 

[Fenves 01] Fenves, S. J. A Core Product Model For Representing Design 

Information (NISTIR 6736). Gaithersburg, MD: National Institute 

for Standards and Technology, 2001. 

[Fenves 03] Fenves, S. J., Y. Choi, B. Gurumoorthy, G. Mocko and R. D. Sriram, 

Master Product Model for the Support of Tighter Integration of

Spatial and Functional Design (NISTIR 7004). Gaithersburg, MD: 

National Institute of Standards and Technology, 2003. 

[Fisher 89] Fisher, G.; McCall, R.; & Morch, A. Design Environments for 

Constructive and Argumentative Design, in Human Factors in 

Computing Systems, K. Brice and C. Lewis (editors). Special Issue 

of SIGCHI Bulletin, 269-275. New York, NY: ACM, 1989. 

[ISO 94] ISO 10303-203:1994, Industrial automation systems and 

integration -- Product data representation and exchange -- 

Part 203: Application protocol: Configuration controlled 

design. 

52 CMU/SEI-2003-TR-013 
[ISO 209:01] ISO 10303-209:2001, Product data representation and 

exchange: Application protocol: Composite and metallic 

structural analysis and related design. 

[ISO 214:01] ISO 10303-214:2001, Industrial automation systems and 

integration -- Product data representation and exchange -- 

Part 214: Application protocol: Core data for automotive 

mechanical design processes 

[ISO 224:01] ISO 10303-224:2001, Industrial automation systems and 

integration -- Product data representation and exchange -- 

Part 224: Application protocol: Mechanical product 

definition for process planning using machining features 

[NRC 99] National Research Council. Advanced Engineering Environments, 

Phase 1. Washington, DC: National Academy Press, 1999. 

[NRC 00] National Research Council. Design in the New Millennium, 

Advanced Engineering Environments, Phase 2. Washington, DC: 

National Academy Press, 2000. 

[PDES 99] PDES Inc. Recommended Practices for AP209. 

<http://pdesinc.aticorp.org/rec_prac.html> (1999). 

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Design 33, 7 (2001):531-543. 

[SPIRC 03] Mitchell, P. & Trichtinger, J. SPIRC-SEI/TIDE Project. Pittsburgh, 

PA: Southwestern Pennsylvania Industrial Resource Center (now 

Catalyst Connection), 2003. 

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July 29-Aug. 1, 2001. ISBN:0-9710461-0-7, 2001.

[Sutton 98] Sutton, P. R. & Director, S. W. “Framework Encapsulations: A New 

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Approach to CAD Tool Interoperability,” 134-139. Proceedings of 

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ACM Press, 1995.

54 CMU/SEI-2003-TR-013 
CMU/SEI-2003-TR-013 55 
Glossary 

2D two-dimensional 

3D three-dimensional 

AEE advanced engineering environment 

ANSI American National Standards Institute 

AP application protocol 

API application program interface 

ASP application service provider 

CAD computer-aided design 

CAE computer-aided engineering 

CAM computer-aided manufacturing 

CORBA Common Object Request Broker Architecture 

CMU Carnegie Mellon University 

COTS commercial off-the-shelf

DOE Design of Experiments 

DPG Design and Process Group (of NIST) 

FEA finite element analysis 

IGES Interim Graphics Exchange Standard 

ISO International Standards Organization 

LAN local area network 

NASA National Aeronautics and Space Administration

NC numerical control 

NIST National Institute of Standards and Technology

NRC National Research Council 

OMG Object Management Group 

PC personal computer 

PDES Product Data Exchange using STEP 

56 CMU/SEI-2003-TR-013 
PDM product data management 

PLM product lifecycle management 

PRP product realization process 

QFD Quality Function Deployment 

RFQ request for quotation 

SEI Software Engineering Institute 

SME small manufacturing enterprise 

STEP STandard for the Exchange of Product model data 

TIDE Technology Insertion, Demonstration, and Evaluation 

URL Uniform Resource Locator 

CMU/SEI-2003-TR-013 57 
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Advanced Engineering Environments for Small Manufacturing 

Enterprises: Volume I 

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Steven Fenves, Ram Sriram, Young Choi, Joseph P Elm, John E. Robert 

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13. ABSTRACT (MAXIMUM 200 WORDS) 

Advanced engineering environments (AEEs) are computational and communications systems that can create 

virtual and/or distributed environments linking researchers, technologists, designers, manufacturers, 

suppliers, and customers, providing for the orderly integration of tools used and data developed during the 

design phase of a product. AEEs consist of design tools (e.g., computer-aided design (CAD), computer-aided 

engineering,), data repositories (e.g., design database, evolution database, ), and the networks linking these 

components and other enterprise processes. 

Although AEEs can improve the productivity of a small manufacturing enterprise (SME), a key barrier to SME 

adoption is a lack of awareness of AEEs. This report provides an overview of AEE technologies for SMEs, 

starting with a description of the levels of AEE capability and a summary of the benefits of AEE technology. 

AEEs for SMEs are most often constructed through the integration of commercial off-the-shelf (COTS) 

information technology (IT) tools, but successful adoption of these tools requires planning and commitment. 

This report provides SMEs with an overview of technical considerations for AEE adoption to enable such 

planning. Interoperability of these tools and efficient communication between the users of these tools is also 

discussed 

14. SUBJECT TERMS 15. NUMBER OF PAGES

16. PRICE CODE

17. SECURITY CLASSIFICATION 

OF REPORT

Unclassified 

18. SECURITY CLASSIFICATION OF 

THIS PAGE

Unclassified 

19. SECURITY CLASSIFICATION OF 

ABSTRACT

Unclassified 

20. LIMITATION OF ABSTRACT

UL 

NSN 7540-01-280-5500 Standard Form 298 (Rev. 2-89) Prescribed by ANSI Std. Z39-18 298-102