The enabling of product information in the conceptual phase

(1)

DOCTORA L T H E S I S

Luleå University of Technology

Department of Applied Physics and Mechanical Engineering Division of Computer Aided Design

The Enabling of

Product Information in the

Conceptual Phase

(2)

(3)

The Enabling of Product

Information in the Conceptual

Phase

PATRIK BOART

May 2007

Division of Computer Aided Design

Department of Applied Physics and Mechanical Engineering Luleå University of Technology

(4)

ISSN: 1402-1544

ISRN: LTU-EX—07/16--SE

Department of Applied Physics and Mechanical Engineering Division of Computer Aided Design

Luleå University of Technology SE-971 87 Luleå

SWEDEN

(5)

Preface

This research has been carried out in corporation between Luleå University of Technology and the Volvo Aero Corporation. The research and case studies were performed at the Design Methods & Systems department at Volvo Aero. I am very grateful for the funding by Volvo Aero and NFFP (VINNOVA’s Nationellt

Flygtekniskt Forskningsprogram), thereby allowing me to concentrate on this specific research area that is close to my passion for engineering and computers.

I would like to express my gratitude to my supervisor, Bengt-Olof Elfström, for his enthusiasm, experience, energy and belief in my ideas and excellent guidance in my research efforts. I would also like to thank Ola Isaksson for always finding some spare time to give me guidance. Thanks to all my colleagues at Volvo Aero who has participated in my research and contributed by educating me in my daily work. At the university I like to thank all my colleagues at the Division of Computer Aided Design for ideas and insights, my co-authors and Lennart Karlsson for making it all possible.

Last I would like to thank my family and friends who have always stood by me giving me their support and comfort.

Luleå, Maj 2007 Patrik Boart

(6)

(7)

Abstract

It is implied that Functional Products fundamentally change how the product

development process is performed in global settings. An extended product definition together with the need to evaluate product properties earlier creates new demands on engineering methods and tools needed during the product development process. A trend is for the customer to want to buy extended solutions provided by many companies in a network. The companies are then forced to cooperate as early as possible in the product development phase to minimize the business risks. Functional products increase the amount of design parameters considered in the conceptual phase. Hardware, manufacturing, service and business parameters are all essential. However, there is a lack of methods to vary the extended set of design parameters in the conceptual design stage.

The aerospace industry as well as other manufacturing companies with an increased product complexity develops their offers together globally, meaning that a design parameter can be distributed between several partners. Changing a parameter forces each partner to perform the necessary activities and share the result to gather the overall view. Inserting the functional product perspective into the aerospace industry creates totally new demands on the product development process with a life cycle perspective. Design parameters not normally involved in the early phases should now be considered. The purpose of this research is to develop a method that can enable this extended set of design parameters to be evaluated and manipulated in the early stages of product development.

The research strategy is to combine participatory action research process with a case study approach and to verify the approach close to technology and product

development activities in industries. The research approach is to combine KBE, CAD and CAE technologies to create a more generative product model, which can

automate activities in the conceptual phase of the product development process. Using a generative technical product model that adapts different design parameter settings extends the set of product properties to be evaluated. The generative model can also be used globally and distributed, enabling the evaluation of an extended set of design parameters in a global and distributed conceptual phase.

With an increased ability to generate different models more product life cycle properties can be simulated and increase the conceptual information basis. This improves the ability to address product life cycle properties for functional product offers already in the conceptual phase.

(8)

(9)

Appended Papers

This thesis is based on the work contained in the papers listed below: Paper A

Boart, P., Nergård, H., Sandberg, M. and Larsson, T.

A multidisciplinary design tool with downstream processes embedded for conceptual design and evaluation.

In the proceeding of International Conference on Engineering Design, ICED 05, August 15-18 2005, Melbourne, Austraila.

Paper B

Sandberg, M., Boart, P. and Larsson, T.

Functional Product Life-cycle Simulation Model for Cost Estimation in Conceptual Design of Jet Engine Components.

Published in Concurrent Engineering: Research and Application. Paper C

Boart, P., Andersson, P. and Elfström, B-O.

Knowledge Enabled Pre-Processing for structural analysis.

In the proceedings of 1st Nordic Conference on Product Lifecycle Management – NordPLM’06, January 25-26 2006, Göteborg, Sweden.

Paper D

Boart, P. and Elfström, B-O.

Making cross-company information available in the conceptual phase.

Published in Computer-Aided Design and Application, Vol. 3, No. 6, 2006, pp 675-682.

Paper E

Boart, P. and Isaksson, O.

Enabling variation of Manufacturing Process Parameters in Early Stages of Product Development.

In the proceedings of 2006 ASME International Mechanical Engineering Congress and Exposition, November 5-10 2006, Chicago, Illinois, USA.

(10)

(11)

1 Introduction

Increased globalization and competition, changes in the value system and technical advances are driving forces addressed in 1999 by Technical Foresight in Sweden [1]. Technical Foresight presents a vision of how these driving forces may affect the development of future product systems. A view is outlined where many companies have been forced to specialize due to the increased complexity in all parts of the product system and increased competition. This increases the need for cooperation between different companies to operate the product system and makes the boundaries of the companies more buoyant. Allowing the project organisation to work in a network creates a need for information sharing methods, as well demands development of methods to operate all parts of the product systems.

Globalization, specialization and new business models have created a need for

product developing companies to perform their product development process globally and distributed, see Figure 1. Functional Products (Total Care Products) are implied to fundamentally change how the product development process is performed globally [2-4]. An extended product definition together with the need to evaluate the product properties earlier creates new demands on engineering methods and tools needed during the product development process.

One challenging factor during product development is time. Time pressure leads to product development decisions often being made without enough information [5]. New information technologies reduce the cost and time of experimentation and enable companies to increase the experimental iterations expanding the available information [6]. Design is about making the best possible decisions throughout the product development process. To accomplish this, the aim is to obtain a full and accurate forecast about the product’s life cycle properties [7]. The use of computer support in the conceptual phase is complicated by the imprecise and incomplete design requirements [8-9]. The lack of design requirements can be compensated by using experience and product strategies [10].

There is a lack of information in the conceptual phase regarding how decisions affect activities performed later (downstream) in the product development process. For example, the manufacturing selection process is dependent on the stage reached in the design process, as this determines the degree of detail required to evaluate the

manufacturing properties [11]. In a product development process the degree of detail increases as the product development process proceeds. Different tools and

methodologies will have to be developed, enabling an assessment of the consequences of different design solutions [12].

To improve available information in the conceptual phase a better use of available technologies is needed.

(14)

Sustainable Society Globally Distributed Engineering Business Models

Total Care Offer (Functional Products) Specialization Conceptual Design Information Technology Knowledge Technology Engineering Design Methods Globalization Increased Product System Complexity

Figure 1. Globalization, specialization and new business models impacts the conceptual phase triggering a more efficient use of information and knowledge technologies to improve the

engineering design methods.

2 Areas Affecting Work in the Conceptual Phase

This chapter describes several areas that affect the requirements on the conceptual phase of the product development process.

2.1 Globalization and Specialization

The global economy is growing and the boundaries between countries are dissolving. Outsourcing product development activities to specialized suppliers allows their specialized design and technology expertise to be used [13-14], thus allowing

companies to focus upon their areas of interest, and facilitate and protect the strategic advantages of market share.

Growing product systems increase the complexity of product development, especially when this becomes a global activity between specialized suppliers located around the world. Today’s Product Data Management (PDM) systems store, manage, control information used to define, manufacture and support products [15].

2.2 The Functional Product

Demands on sustainable growth add complexity to the product development activity challenging multinational companies to develop new business strategies [16]. One business strategy is to take a holistic product perspective where products and services are seen as parts of a market offer. The holistic product perspective will have

(15)

important implications in managing product and service development and to communicate between marketing and engineering.

To address a typical holistic product in business-to-business relations the aerospace industry uses the term functional product (total care product). The term addresses the new product development requirements during product development in aerospace [17]. In this offer the customer buys the function of the product instead of the product itself, meaning that the product provider will be responsible to deliver the function throughout the life cycle of the product. The product provider will then own the product and be responsible for all costs to develop, manufacture, support and continuously upgrade the product.

Before the 1990s, services were seen as add-ons to the physical artefact within product offers from the aerospace industry. In this business model, most of the profits are made on aftermarket activities such as maintenance and spare parts. Even if this type of offer still exists a clear trend is that it is moving towards a business model of selling the function of the product instead. Products developed in the interest of making profit on the aftermarket may then become high-risk products when the ownership is transferred from the customer to the function provider.

Another trend for the customer is to buy more comprehensive solutions provided by many companies in a network [3]. These companies will then be forced to cooperate as early as possible in the product development phase to minimize the risks. The concept phase becomes most important with a development process supported by very fast simulation tools to achieve many iterations and the possibility to optimize over the total system.

One trigger for industrial Functional Products is the interest to control the aftermarket activities for the physical artefact. The driving force to control the aftermarket also enables ecological sustainability, through remanufacturing and design with respect to technological advances [3], and minimises the cost of maintenance and spare parts because it is at the provider’s own cost. Fundamentally, this evolving view implies an extension of the product development companies life-cycle commitments (i.e.

suppliers retain ownership throughout the total life-cycle) and an increased demand to collaborate in global alliances between value chain partners (i.e. the extended

enterprise) [2]. Extending the life-cycle commitment creates new demands on the hardware development process with additional needs and requirements emanating from the aftermarket. One challenge is to integrate environmental requirements throughout the entire lifetime of a product, requiring a new way of thinking and new decision tools to be applied [18]. In a larger perspective, future customers will judge the physical artefact by the functions it provides, i.e. an optimisation to the

customer’s business as a whole. Table 1 presents two different definitions of functional products.

(16)

Table 1. Functional Product definitions.

Definitions of the term Functional Products Authors

Functional P = products, also known as ‘total care products’, are products that comprise combinations of ‘hard’ and ‘soft’ elements. Typically, they are described as comprising hardware combined with a service support system.

Alonso-Rasgado et al. [3]

A Functional Product (FP) is an offer developed by a network of companies and consisting of capital intensive hardware integrated with accompanying services that are necessary for keeping it operational during the lifecycle

Karlsson, L. et al. [2]

Developing a functional (Total Care) product in a Business-to-Business relation creates a need to share information between the involved companies. As the development of the functional products includes the development of both hardware and accompanying services, people from all areas and their knowledge will be needed in the decision-making.

Even if there are well-established methods for design [3,19,20], one major challenge when addressing the life cycle aspects of a functional product is the new methods in the conceptual design phase.

2.3 Information Technologies in the Conceptual Design Phase

Information technologies are computers and software used to generate information. These technologies are rapidly evolving and generating new abilities, requiring the development of new methods and tools.

It is widely accepted that much of the product cost is already committed in the conceptual design phase, while occurring later in the process. Thomke and Fujimoto [21] present a conceptual model of front-loading, a concept that moves problem-identification and solving upstream in the product development process.

“We define front-loading as a strategy that seeks to reduce development time and cost by shifting the identification and solving of [design] problems to earlier phases of product development”

One approach identified by Thomke and Fujimoto that supports front-loading is effective deployment of advanced technologies and methods.

To take design decisions, engineers are involved in an iterative process, where the engineer uses methods, models and computer support to play with different design parameters. Different design parameter settings result in different expected properties that need to be evaluated before decision-making.

(17)

2.3.1 The Bottleneck of Preparing Analysis Models

Today, industry best practice allows 3D analyses to be made for many Design Parameters (DP’s). For Manufacturing Process Parameters, the preparation lead time is still a bottleneck for early phase design. Prasad [22] addressed a challenge to “Consider manufacturing constraints up-front e.g., during a conceptual stage of a

product development process”. This challenge today is due to the time to generate

advanced analysis models, each requiring several weeks to build.

To predict product properties engineers build different models. FE models are one type of model. Depending on what kind of FE model the time to generate them can span from hours to weeks. Important product properties needed early are quite often dependent on models that are time consuming to generate, creating problems during the earlier phases when the time pressure is greater.

Finite Element Methods have been used since the early 1970s to predict stresses and deformations resulting from welding [23-24]. Eliott [25] described how a manually prepared 3D finite element idealization of a diesel engine piston occupied a qualified engineer for four weeks full time during the late-70s. Eliott claimed that interactive graphical pre-processing and automatic generation may cut the pre-processing time to a few days. Rather than cutting the lead-time for simplified models the size and complexity of analysis models tend to increase. Consequently, the time for

performing the pre-processing still constitutes a significant proportion of the total. Due to the lack of computer power two-dimensional analysis was mainly used until the late 1980s when the first three-dimensional methods started to appear [26-27]. In the conceptual phase where the pre-processing, analysis and post-processing times must remain short, two-dimensional models and material models are preferred to reduce pre-processing and analysis time [28]. A two-dimensional model is not good enough if the magnitude of stresses and deformations is needed in three dimensions. To allow three-dimensional models to be used in the conceptual phase, methods that can reduce the pre-processing and analysis times are needed.

2.4 Knowledge Technologies in the Conceptual Design Phase

Knowledge technologies are important since they enable knowledge storage and thereby support design processes. By supporting the design processes with knowledge technologies the lead-time of performing engineering activities can be reduced as the quality of the supported activities increases.

2.4.1 Knowledge Based Systems

Knowledge Based Systems (KBS) and especially Knowledge Based Engineering (KBE) Systems are being used more frequently to store knowledge and support design processes, see Table 2. Historically, principles from Expert Systems

technology and CAD systems were used to develop KBE. Expert Systems coupled to CAD-tools emerged in the 1970s as a way of controlling and evaluating the geometry by means of rules [29]. These same types of models are often repeatedly created and

(18)

contain a minimum of innovation and little reuse of pre-existing know-how [30]. Parametric CAD-models store some amount of design knowledge, enabling the solid model to be scaled and reused. However, it is difficult to make “traditional”

parametric models that allow topological changes in the geometry. Likewise, it is not obvious how to associate non-geometric design variables to the parametric CAD model. Expert systems have previously been used to solve these issues. Numerous knowledge- modelling techniques have been used to support different steps in the product development. Table 3 show where and how they have been used.

There have been many development methodologies suggested for the KBS domain, such as KADS and STAGES [30]. One commonly used methodology for building KBE systems is MOKA. MOKA provides the elements needed to structure knowledge and to build representations of it, prior to producing code for KBE platforms [31].

Numerous efforts have been done to support different disciplines where many knowledge-modelling techniques have been developed. The main idea has been to show how these methods can reduce the lead-time of the product development process and increase the quality of the processes. So far, methods used to improve the basis for conceptual decisions have received little attention. Today’s effort mostly comes from design and manufacturing analysis. To gain knowledge of how the life cycle of a product will be affected by early decisions, more disciplines need to be involved.

2.5 Engineering Design Methods in the Conceptual Phase

The main idea of an engineering design method is to support and improve a design activity. Still, few methods presented within academia have been widely adopted in industry, even though the industrial needs are evident and the application potential stated [32-33]. To improve engineering design research, Blessing has worked on a research methodology to improve the current status and make design research an established scientific discipline [34].

“the formulation and validation of models and theories about the phenomenon of design as well as the development and validation of knowledge methods and tools – founded on these models and theories – in order to improve the design process”

Blessing [34].

To take design decisions, engineers are involved in an iterative process. Roosenburg and Eekels [35] illustrate this in the Basic Design Cycle, shown in Figure 2. In this iterative process the engineer uses his methods, models and computer support to play with different design parameters. Different design parameter settings result in

(19)

Table 2. Definitions on KBS and KBE.

Definitions on KBS and KBE Author

“Knowledge Based Systems are a special class of computer programs that purport to perform, or assist humans in performing, specified intellectual tasks.”

Dixon [36]

“KBE systems aim to capture product and process information in such a way as to allow businesses to model engineering design processes, and then use the model to automate all or part of the process.”

Chapman and Pinfold [37]

“A Knowledge-Based System is the one that captures the expertise of individuals within a particular field, and incorporates it and makes it available within a computerized application.

A KBE application is further specialized and typically has the following components: Geometry, Configuration and Engineering Knowledge.”

Lovett [38]

“KBE is a technology that allows an engineer to create a product model based on rules that capture the methodology used to design, configure and assemble products.

KBE facilitates the capture of the intent behind the product design by representing the why and how in addition to the what of a design.”

Bailey [39]

“Knowledge Based Engineering is the execution of engineering tasks using knowledge that is not normally immediately accessible to the designer or engineer, and that has been purposefully accumulated and stored for use by the designer or engineer, usually (but not always) in some computer-mediated form. Thus, KBE usually (but not always) implies the use of some kind of computer system, examples of which include the so-called expert systems, web-based knowledge bases, and the like.”

Penoyer & Burnett [40]

Knowledge Based Engineering:

“The use of advanced software techniques to capture and re-use product and process knowledge in an integrated way.”

Stokes [31]

One of the most challenging aspects of product development is to manage trade-offs [3]. Reducing the weight of the product can improve performance, but will probably increase manufacturing cost. To understand how different design parameter settings impact different disciplines, information must be shared.

2.5.1 Concurrent Engineering

Concurrent Engineering (CE) is a method to improve integration between different disciplines in a company’s product development process [41]. The integration allows the different disciplines to work more in parallel shortening the development time and improving the information exchange. Kusiak [12] describes CE as:

“...the practice of incorporating various values of a product into the design at its early stages of development. These values address the entire life cycle of the product and include not only its primary functionality but also the ability of manufacturing, assembling, testing, service and recycling.”

(20)

Table 3. Knowledge Modelling Techniques. Knowledge

Modelling Technique

Product Discipline Discipline relationship Author

Expert system (ES)

Generic Design, Manufacturing

Feature extraction and cost estimation of manufacturing

Venkatachalam, 1993 [42] Kitchen

design

Design Capturing of design rationale for design of kitchen Mørch, 1994 [43] Design rationale (DR) Chemical Plant

Design Capturing of design rationale behind a chemical plants

Chung and Goodwin, 1998 [44]

Wing Structure

Performance and manufacturing

Performance and manufacturing analysis of a wing Zweber et al., 1998 [45] Wing Structure Design, Cost analysis

Design, Cost estimation (manufacturing concerns)

Blair and Hartong, 2000 [46]

Car body structure

Design, Analysis Pre-processing of design Chapman and Pinfold, 2001 [37] Aerospace Design, Analysis,

Manufacturing

Manufacturing and performance evaluation of design

Schueler and Hale, 2002 [47]

Knowledge based engineering (KBE)

Buildings Design, Analysis Cost estimation, scheduling on buildings

Mohamed and Celik, 2002 [48]

- Manufacturing, Analysis

Moulding evaluation Lou et al., 2004 [49] Insurance Analysis Risk analysis of drivers Daengdej et al. ,1999

[50] Low Power

Transformers

Design, Analysis Product and process design Kwong and Tam, 2002 [51]

- Design, Analysis Material selection Amen and Vomacka,

2001 [52] Travel

Agency

Analysis Travel planner Chaudhury et al.,

2004 [53] Agents and case based reasoning (CBR) Induction motors

Product Support Diagnostics Yang et al., 2004

[54]

Prasad [22] described design as an open ended problem where each decision limits possible solutions until the final solution is created. The challenge is to take decisions that lead to a successful product.

2.6 Conceptual Design of Functional Products

Functional products increase the amount of design parameters to be considered in the conceptual phase, Figure 3. Hardware, manufacturing, service and business

parameters are all essential. The problem is a lack of methods that allow a variation of this extra set of design parameters in the conceptual design stage [2]. The

aerospace industry is jointly developing their offers globally. The variation of Design Parameters requires a tightly coordinated decision-making process between partners. Changing a design parameter forces each partner to perform the necessary activities and share the results to gather an overall view.

(21)

Analysis Synthesis Simulation Evaluation Decision Criteria Provisional Design Expected properties Value of design Approved design

Figure 2. The Basic Design Cycle by Roosenburg et al.

FP • Repair /exchange • Recycle • Upgrade • … • Tolerances • Casting / fabric • Material properties • … • Dimensions • Material properties • Tolerances • … • Return of capital • Brand • Environment • Safety • Assurance •… Hardware Parameters Service Parameters Business Parameters Manufacturing Parameters

Figure 3. Functional Product Design Parameters.

Working globally together in the new virtual environments presented as services on different websites does not give a better view in the early phases. The iteration cycle

(22)

is presently too long to allow iteration over the entire aerospace system. Virtual environments allow the sharing of activities, but do not increase the speed to perform the activities needed to evaluate different parameter settings.

2.7 Purpose and Limitation of the Research Project

The purpose of this research project is to develop methods that allow an extended set of design parameters in the conceptual phase of the globally distributed product development process to be evaluated and better address the product life cycle properties of a total offer.

The research process was performed within the aerospace business. However, some cooperative studies were conducted in the automotive and tool manufacturing industries. The studied development process and methods are commonly used by the above-mentioned industries. The information technology environment has evolved during the research process following the aerospace industry’s needs.

3 Industrial Frame of References

This research project began in 2002 as a strategic approach from Volvo Aero to create the means needed to define and evaluate conceptual jet engine components where hardware only represents part of the product. This research projects was conducted within the framework of National Aeronautics Research Program (NFFP) [55], founded by the Swedish government with the aim to create the necessary conditions for Swedish participation in international research programs within aerospace. The purpose of NFFP is to strengthen the competitiveness of Swedish aerospace by reinforcing and coordinating national research resources in industries, institutes and universities.

A close relation to Luleå University of Technology (LTU) and Volvo Aero has enabled this research to be performed closely with people in the industrial and academic environments. Not only has this occurred internally at Volvo Aero, but also externally through other research projects within LTU such as ProViking, VIVACE, the Polhem Laboratory and the Faste Laboratory research.

Figure 4 presents all stakeholders and how they are located within this research project. The European aerospace industry is searching for processes, models and methods to develop their products more efficiently. The integrated project VIVACE [56], EC Frame Work 6 program is an aeronautical collaborative design environment with associated processes, models, methods and tools. This environment will help to design an aircraft and its engines as a whole, and provide all requested functionality and components in each phase of the product-engineering life cycle of the virtual product to the aeronautics supply chain in an extended enterprise. The project consists of 52 partners, 35 companies, 6 research institutes and 11 universities. Luleå University of Technology (LTU, www.ltu.se) is one of the partners in

(23)

concurrent engineering and functional products. The Faste laboratory sponsored by VINNOVA, LTU and companies will now focus on Functional Product Innovation. Within LTU a new guest professorship in Functional Products has been created. To strengthen Sweden’s competitiveness, The Foundation for Strategic Research in Sweden aims to support research in engineering, materials and medicine science. ProViking [57] is a program within the foundation whose purpose is to strengthen the competitiveness of the Swedish manufacturing industry. This program should create improved production systems and new methods for product development through projects conducted between industry and academia. The research result should be transferable and used in the Swedish industry to give cost-efficient production and new or improved products that are competitive on the international market. LTU has made interaction between VIVACE, NFFP, ProViking, the Polhem Laboratory and the Faste Laboratory possible, thus creating a wide basis for the research, see Figure 4.

Volvo Aero (www.volvo.se), whose business idea is to be an independent risk and revenue sharing partner in cooperation with major engine manufacturers, develops and manufactures components for commercial and military aircraft engines and gas turbines. They are partners with GE in the GEnx engine for Boeing’s new 787 Dreamliner aircraft, where they are responsible for the design, development, manufacturing and product support of the Fan Hub Frame, Turbine Rear Frame and Booster Spool, and with Rolls Royce in the Trent 900 engine for the super jumbo Airbus A380, where they are responsible for the design, development and

manufacturing of the Intermediate Compressor Case, a complex structural component between the IP and HP compressors. Here, their responsibility covers the

development, design, manufacturing and product support for the supply of spare parts throughout the entire lifetime of the engine. The company’s specialization strategy has proven highly successful: more than 80 percent of all new commercial aircraft with 100 or more seats are equipped with engine components from Volvo Aero. Volvo Aero is one of the few companies in the European space program that provides rocket engine turbines and combustion chambers/ nozzles. Over the last 25 years, Volvo Aero has produced more than 1,000 combustion chambers and nozzles for the Ariane 4’s and 5’s.

(24)

Customer RR LTU NFFP VINNOVA This thesis SFF EC FP6 VIVACE Polhem Faste National EC Figure 1 VAC Figure 4. Stakeholders.

4 Research Question

The research question was gradually developed during the research process. At the beginning of the research project the author was confronted with the total care offer and the functional product perspective. The initial research question was formulated as:

How is the engine component conceptual design process affected by a service provision approach?

From the limitations needed to reduce the scope of the research the final research question was defined as:

How can an extended set of design parameters be evaluated in the conceptual phase of the globally distributed product development process to better address product life cycle properties for total offers?

5 Research Strategies

To investigate the research question the following strategy is outlined. The research approach is:

- to study and improve the efficiency of the conceptual product development process

- to develop a methodology to use a combination of KBE, CAD and CAE technologies to create a more generative product model which can automate activities in the conceptual phase of the product development process - to use participatory action research with a case study strategy

- to verify the research approach by case studies close to technology and product development activities in industries.

(25)

5.1 Process, Methodology and Tools Development

Industries have developed their products through a gated process during the last 20 years. This process at AB Volvo is named the Global Development Process (GDP), see Figure 5. Volvo’s ability to structurally execute projects is critical to their success. GDP is the basis of this structure.

Figure 5. Global Development Process (GDP).

The gates are GDP checkpoints, where Project Management confirms that the gate criteria are met for the current gate, demonstrates preparation for the next gate and updates the project prediction of final delivery and associated risks. At each gate certain decisions need to be made by conducting work between the gates to gather the needed information. In this research most of the work was carried out in the

conceptual study phase between gate 1 and gate 2, see Figure 6.

The approach taken here is to use a combination of KBE, CAD and CAE technologies to automate activities in the conceptual phase of the product development process. Activities with too long lead times are shortened and

performed within the conceptual time frame. Each extra-performed activity builds up available information regarding the products prediction of final delivery and

associated risks.

KBE technology uses a functional programming technique closely coupled to the CAD or CAE system. KBE allows the building of a program that performs an activity within the CAD or CAE system. By executing the program the activity within the CAD or CAE system follows the instructions given by the KBE system, thus reducing the time to generate models needed to simulate downstream product properties.

Figure 7 illustrates how three pre-processing activities can be captured and performed by a program. This program is built up by combining the advantages of KBE, CAD and CAE techniques.

(26)

Figure 6. The Global Product Development Process as a flow chart. Program KBE CAD CAE Requirement Specification Geometry Definition Geometry Idealization Mesh Generation Solver Input Definition Analysis Post Processing Requirement Specification Geometry Definition Program Analysis Post Processing

Figure 7. KBE,CAD and CAE combined in a program that automates three pre-processing activities.

(27)

5.1.1 The Ability of the KBE System

The KBE system uses a functional programming language closely integrated into the CAD and CAE system, see Figure 8. The functional programming language support lazy evaluation and object oriented programming [58]. With a KBE system

controlling the CAD or CAE system, it becomes possible to go from manually building geometry or analysis models to building a program that performs the same activity. By executing the program with different parameter settings different geometries or analysis models can be generated.

KBE

A functional programming language • Object oriented

• Lazy evaluation

• CAD functionality integrated • CAE functionality integrated

Figure 8. KBE based on functional programming language with CAD and CAE functionality integrated.

This approach was used to capture activities from different product development processes described in case studies 1 to 4.

5.2 The Research Methodology of this Thesis: The Participatory Action Research Process using a Case Study Strategy

The research methodology is to combine participatory action research process (described in chapter 5.3) with a case study strategy (described in chapter 5.4) and is named by the author as Participatory Action Research process using a Case Study Strategy (PARCSS).

The research was performed with an exploitative approach by testing how well computer support can be used to bring downstream parameters to the conceptual phase. The strategy initially explored what is possible through pilot studies. The possibilities were then introduced into the industrial product development process through case studies. When the case studies were successful, the approach was implemented and used in real product development projects.

This section describes a five-step approach with a participatory action research process using a case study strategy, see Figure 9. In Figure 9 the approach is composed of one action cycle, one case study cycle and one research cycle. The action cycle and research cycle comes from the participatory action research process (described in chapter 5.3) and the case study cycle comes from the case study research process (described in chapter 5.4) The action research process is of a

participatory form, as the researcher participates in both the action cycle and research cycle, defining and performing case studies together with participants from the process addressing the problem. The strategy consists of two different case study

(28)

approaches called the pilot case study and case study. The Pilot case is used initially to increase the understanding of the topic studied as well as investigate what

possibilities exist with new techniques (KBE technologies in this case). If the pilot study was successful, the next step is to generate a case study. Both studies were preformed with the process described in Figure 9.

1. Identify problems to solve and other opportunities, causal factors, environmental

constraints and relevant practice.

2. Formulate proposed changes and the implementation plan.

3. Initiate changes in target areas.

4. Asses changes and implementation.

5. Deepen, institutionalize and diffuse change.

Action Cycle

1. Define research question.

2. Design case study.

3. Perform case study.

4. Collect evidence.

5. Analyze the result.

Case Study Cycle

1. Define research question.

5. Analyze the result. 1. Define research question.

5. Analyze the result.

Case Study Cycle

1. Identify topic to study and review relevant knowledge.

2. Operationalize hypotheses.

3. Select sample to observe.

4. Select other research methods, gather data, and generate findings. 5. Derive and

disseminate implications for theory and practice.

Research Cycle

disseminate implications for theory and practice. 1. Identify topic to study and review relevant knowledge.

Research Cycle

Figure 9. Participatory Action Research Process using a Case Study Strategy: based on [59-60].

The first step in the PARCSS cycle is to identify problems, topic to study and to define a research question for the case study. This step can also be compared to the first step in Blessing et al. [61] research methodology framework.

To address the initial problems discussed in the introduction where the conceptual phase lacks information a success criterion is defined (step 1 in PARCSS):

Increase the available information in the conceptual phase of the globally distributed product development process to better address product life cycle properties for total offers.

Case studies have been used to introduce different automation attempts some with a more pilot approach and others directly into real projects. Pilot case studies have been used to explore what factors that influence the criterion. During a pilot case study attempt is made to answer the research questions without measuring the details of success. With less measuring of details enables iteration over the entire PARCSS cycle (step 1 to 5) to be performed. More information is then generated which later can be used to understand what factors that influence the criterion. This information about the important factors is critical to the success in defining case studies needed to answer the research question of interest.

(29)

To understand the participatory action research approach one need to understand the environment from where the research has been conducted. As a researcher moving between participating and observing the team building engineering support systems, has enabled access directly into the company’s product development processes and the people addressing their needs. To illustrate the research process Figure 10 is used. Focus Criteria Synthesis System Support Development Process Synthesis System Support Development Process Result Analysis

• Reduce lead time • Improve quality • Improve availability

Product Development Process

A

c

ti

v

ity

Figure 10. System Support Development Process.

From the identified needs in the product development process (e.g. reduce lead time, improve quality and increase availability to the weld simulation pre-process activity), a focus criterion is defined. From the addressed need the system support team begins to synthesising and generating solutions that can fulfil the needs. The solutions ability to solve the focus criteria is evaluated.

5.2.1 Synthesising New Automation Solutions

Working in a team has helped my research as the team members educate each other about their new findings and consequently gather more information for me than I would be able to do by myself. I have often received new information through only observing discussions between team members. Another benefit of working as a team is that one can have several projects running in parallel to generate more results in a shorter timeframe.

5.2.2 Analysis

When the result of the developed support system becomes available the work to verify how well it solves the initial criteria begins. If the approach is successful the next step is to implement the method into the product development process. This usually means that the method in the implementation process is improved when new requirements are addressed.

(30)

5.3 Participatory Action Research

5.3.1 What is Participatory Action Research

A participatory action research (PAR) approach was used in this study to verify the hypothesis. Participatory action research is explained by Wadsworth [62] as

“ … participatory action research is not just research which we hope will be followed by action! It is action which is researched, changed and re-researched, within the research process by participants. Nor is it simply an exotic variant of consultation. Instead, it aims to be active co-research, by and for those to be helped. Nor can it be used by one group of people to get another group of people to do what is thought best for them - whether that is to implement a central policy or an

organisational or service change. Instead it tries to be a genuinely democratic or non-coercive process whereby those to be helped, determine the purposes and

outcomes of their own inquiry. Paradoxically it is quite close to a common-sense way of ‘learning by doing’. But at the same time it is very hard to achieve the ideal conditions for putting it fully into practice”.

In participatory action research, the case created inside a company’s own process consists of suitable actions to conduct research upon. By arranging the case in the actual product development process, those to be helped in the process determine the purposes and outcomes of their own inquiry.

5.3.2 The Participatory Action Research Process

The PAR process is divided into five steps, see Figure 11. The action cycle is performed in parallel with the research cycle. Each step of the research process can be viewed as potentially contributing to or being informed by the corresponding aspect of the action process. At each stage, broadening the pattern of participation can potentially strengthen both the knowledge and the action outcomes.

5.3.3 Quality Criteria for Action Research

Herr and Andersson [63] offer the following goals of action research and validity criteria to create a dialogue with both academics and practitioners, see Table 4. Each criteria is described accordingly to Table 5.

Rigour in action research refers to how the data are generated, gathered, explored and evaluated, and how events are questioned and interpreted through multiple action research cycles, see Table 6.

(31)

constraints and relevant practice. 2. Formulate proposed changes and the implementation plan.

Action Cycle

Research Cycle

disseminate implications for theory and practice. 1. Identify topic to study and review relevant knowledge.

Research Cycle

Figure 11. Action, Research and their Potential Integration ([59] page 123).

Table 4. Goals of Action Research ([63] page 55)

Goals of action research Quality/validity criteria

1) The generation of new knowledge Dialogic and process validity 2) The achievement of action-oriented

outcomes Outcome validity

3) The education of both researcher and

participants Catalytic validity

4) Results that are relevant to the local

setting Democratic validity

5) A sound and appropriate research

methodology Process validity

5.3.4 The Insider Collaborating with Other Insiders

The participatory action research process is a very democratic approach, when it works.

“…participation may be stronger at the problem-posing and data-gathering part of the study” ([63] page 32)

Participation is not achieved by only being on the inside. Relations need to be built up. In a working environment relations are built up by contributing to the daily work or becoming involved in informal discussions during coffee breaks, etc.

Still, having access to all the data, one needs to be careful and examine the data to reveal its source of origin.

“..tacit knowledge is an advantage in that it would have to be reproduced from scratch through ethnographic observation at a new site. However, it raises

(32)

epistemological problems in the sense that unexamined, tacit knowledge of a site tends to be impressionistic, full of bias, prejudice, and unexamined impressions and assumptions that need to be surfaced and examined. Further more, insiders, because they are often true believers in their particular practices, are too often tempted to put a positive spin on their data.” ([63] page 35)

Table 5. Quality/validity criteria descriptions ([63] page 55). Quality/validity criteria Description

Outcome validity The extent to which actions occur, which leads to a resolution of the problem that led to the study Process Validity

To what extent problems are framed and solved in a manner that permits ongoing learning of the individual or system.

Democratic validity

The extent to which research is done in collaboration with all parties who have a stake in the problem under investigation

Catalytic validity

The degree to which the research process reorients, focuses, and energizes participants toward knowing reality in order to transform it

Dialogic validity How well the definition of problems and its findings fit with the intuitions of the practitioner community

Table 6. How to maintain rigour in action research ([64] page 28). Description

1 How you engaged in the steps of multiple and repetitious action research cycles (how diagnosing, planning, taking action and evaluating were done), and how these were recorded to reflect their true representation of what was studied.

2

How you challenged and tested your own assumptions and interpretations of what was happening continuously through the project, by means of content, process and premise reflection, so that your familiarity with and closeness to the issues are exposed to critique.

3 How you accessed different views of what was happening, which probably produced both confirming and contradictory interpretations.

4

How your interpretations and diagnoses are grounded in scholarly theory, rigorously applied, and how project outcomes are challenged, supported or disconfirmed in terms of theories underpinning those interpretations and diagnoses.

5.4 Case Study Research

5.4.1 What is Case Study Research?

Accordingly to Yin [60] the preferable research strategy of performing case studies is when a “how” or “why” question is being asked about a contemporary set of events that the investigator has little or no control over, see Table 7. As this is the case here where a “how” research question is included, a case study strategy seems the best choice.

(33)

“In other words, the case study as a research strategy comprises an all-encompassing

method – covering the logic of design, data collection techniques, and specific approaches to data analysis. In this sensem the case study is not either a data collection tactic of merely a design feature alone (Stoecker, 1991) but a comprehensive research strategy” ([60] page 14)

Table 7. Relevant situations for different Research Strategies (original source: COSMOS Corporation) [60] page 5. Strategy Form if Research

question Requires Control of Behavioral Events Focuses on contemporary events

Experiment How,why? Yes Yes

Survey Who,what,where,how

many, how much No Yes

Archical analysis

Who,what where, how many, how

much?

No Yes/No

History How,why? No No

Case study How,why? No Yes

To perform experiments with an exploratory motive, one usable research approach is exploratory case studies [60].

However, choosing the case study method does not mean that one could proceed to the data collection phase. The relevant field contact depends on an understanding – or theory – of what is being studied ([60] page 28).

5.4.2 Pilot Case Study (the role of a Laboratory)

A pilot case study allows a much broader approach of observing different phenomena from many different angles ([60] page 78), see Figure 12. It is also a good method to gather knowledge and information about the phenomena of interest. This method can be seen as an initial attempt to answer the research question without measuring the details of success. Pilot cases are of a qualitative nature and have been used as the initial attempt to understand the activity being captured. A pilot case is used as an initial test of the hypothesis possibilities to answer the research question. For a positive outcome the hypothesis can be further investigated, thus creating new case studies where the method is implemented. When the method can finally be tested in a real environment, measuring the success of the change becomes possible.

5.4.3 The Case Study Process

After a successful pilot case study has indicated that the research question can

perhaps be answered, the creation of a case study is the next approach. The case study is implemented directly in an actual industrial project where it is possible to measure the effectiveness of the implemented methods.

(34)

“The essence of a case study, the central tendency among all types of case study, is that it tries to illuminate a decision or set of decisions: why they were taken, how they were implemented, and with what result.” (Schramm, 1971, emphasis added, [60]

page 12).

6 Case Studies – Results and Analysis

In participatory action research, the case created inside a company’s own process consists of suitable actions to conduct research upon. By arranging the case of the actual product development process, those to be helped in the process determine the purposes and outcomes of their own inquiry [62]. Figure 13 describes the relation between the case studies and published papers in this thesis.

6.1 The Participatory Action Research Process

This section will enumerate the participatory action research process where 11 applications were developed and tested during this thesis work, see Table 8. As a researcher stationed at an aerospace manufacturing company working with the development of computer support in the conceptual phase, participatory action research became a natural way to perform the research. The conditions for participatory action research are ideal, since its purpose is initially stated at the company, which attempts to go from hardware development to the development of functional products. Develop theory Select cases Design data collection protocol Conduct 1st case study Write individual case report Define & design Prepare, collect & analyze

Draw cross-case conclusions Modify theory Develop policy implications Conduct 2st case study Conduct remaining case studies Write individual case reports Write individual case report Write cross-case report Analyze & conclude

(35)

Globalization, specialization and new business Thesis Analysis Discussion Conclusions Research approach Research Question Scientific Contribution Industrial Contribution Future Work Case Study 1 Case Study 2 Case Study 3 Case Study 4 Paper A Paper B Paper C Paper E Paper D

Figure 13. Structural View of the Thesis.

The first seven applications developed were mainly used to test the possibilities available in the commercial system used at the company, see Table 8 and Figure 14. Application 8 to 10 are brought to a higher level of maturity and tested in real projects. During the testing of the systems, a close relation was built up between the system’s providers, allowing the needed functionality to be directly integrated into the commercial system.

Participating in a project (case study) with people who have knowledge regarding how the activity of interest should be performed also allows me to perform with them the participatory action cycle with a case study strategy. This enables:

1. Identifying opportunities, causal factors and environmental constraints, and discussing it together to address the actual problem to solve.

2. Arranging a development and implementation plan.

3. Starting a case study and initiating developed capability in the target areas. 4. Full access to how the changes in the target area work.

(36)

Table 8. The main purpose investigated in the different applications.

Application Purpose Studies

1

Pilot test of Knowledge Fusions abilities to generate Intermediate Case shell geometry and a initial meshing test

Master thesis

2 Pilot test to generate a solid and shell Turbine Rear

Frame geometry Observed study

3

Design parameters coupled to downstream processes from design, manufacturing and maintenance activities enable the ability to analyze their impact on each other.

Case study 1

4 A smaller application to automate the generation of

standard bosses Observed study

5

A first study to generate an Intermediate Compressor Case solid and shell model where assembly

technologies are used

Observed and participated study 6 A smaller application to automate the generation of

standard inserts Observed study

7 This application is used to automate the pre-process

activities Case study 2

8

This application is used to automate the pre-process activity, but with a parametric approach combined with knowledge fusion.

Case study 2

9 This application is used to automate the generation of

the blades from the aero definition Observed study

10 This application is used to automate the pre-processing

step during the generation of a weld simulation model. Case study 4 11 System support for cross-company cooperation in the

development process Case study 3

This process can then be iterated until a satisfactory improvement is reached. To ensure the data collection quality, the strategy is to fulfil Yin’s three tests considered relevant for my research:

1. Construct validity: the operational measures are the people being supported. Having them in the same team to analyse the effect of the implementation gives direct access to operational measures of the concept implementation being tested.

2. External validity: the technique has been used outside Volvo Aero in other areas. The researcher has supported work in other companies (Sandvik, SAAB Automobile).

3. Reliability: implemented support was used between different products and concepts (success of repeat).

When working to support an activity in one of the company processes, a number of factors affecting the reliability and validity of the data collected exist. Information regarding development process activities is stored in company archives in the form of design instructions, earlier project documentation, etc. Still, using these instructions

(37)

normally requires knowledge from the people within the organization. Building a support system of an activity requires information (design instructions) and knowledge (people in the organization) of how the activity should be performed.

(38)

According to Yin, it is important to have a purpose of the collected source and understand the level of quality and reliability of what has been collected. I have participated in evaluating, interpreting, and reflecting upon the data generated through the research process and gone through a rigorous process of checking the facts with those having firsthand knowledge before the analysis of any reports are written, as suggested by Whyte [59].

By working on the inside, I can analyse the documentation and the archival records and have access to the people who have written them. Access has not been a problem in this research.

The main source of evidence has been collected through participation and direct observations.

6.2 Case Study 1: Flange Design Application

The main objective with the initial and first case study was to explore how computer system support can be used to make downstream parameters available in the

conceptual phase. A case to support a flange design process was chosen, since it involves aspects of design, manufacturing and maintenance. It was decided that design parameters of a rotational symmetric flange joint would be suitable, see Figure 15. This flange joint constitutes an important function within jet engines, acting as an interface or link between different parts. It transfers loads, while keeping the engine free from leakage. The bolts used in the flange joint have to keep the joint tight during engine operation. As always in design projects, several disciplines are involved to create a product. Factors to be considered when designing a new bolt connection are loads, leakage and accessibility. The leakage problem is also

dependent on the surface roughness between the two joining flanges, which in turn is dependent on the manufacturing process. The flange geometry is not only determined by geometrical restrictions from the surrounding components, but also the ability to make assembly and maintenance efficient.

Load Load

Geometric Dimensions

Sealing requirements - Surface roughness Torque

Requirement • Manufacturing Req. • Performance Req. • Maintenance Req. Easy to assemble Radius

Figure 15. Section of a circular flange with its requirements and loads.

Case study 1 was done in cooperation with two other Ph.D students from Luleå University of Technology (the outsiders). They were responsible for the manufacturing and maintenance parameters and I was responsible for the performance parameters.

The enabling of product information in the conceptual phase

DOCTORA L T H E S I S

The Enabling of

Product Information in the

Conceptual Phase

The Enabling of Product

Information in the Conceptual

Phase

PATRIK BOART

May 2007

Preface

Abstract

Appended Papers

Contents

1 Introduction

2 Areas Affecting Work in the Conceptual Phase

3 Industrial Frame of References

4 Research Question

5 Research Strategies

6 Case Studies – Results and Analysis