Function Behavior Structure Research Articles

Multilevel topology optimization

The paper proposes an extension of the Function-Behaviour-Structure (FBS) framework to multi-levelc design representation. The ontology based on function, behaviour and structure has been enriched with a new design entity, the topology, with the aim of connecting more levels of representation. According to this new paradigm, design activity is not focused exclusively on working principle, shape and material at macro level, but goes beyond, to greater levels of detail, designing for example how to dispose material in the inner structure of the product parts at microscopic level. Structural optimizers are excellent tools to design the topology of a structure according to its function and behaviour, but they have been conceived for working only at mono-level. This paper proposes a multi-step optimization process for improving the versatility of structural optimization tools allowing them working also in both macro and microscopic dimensional scales.

A FBS-based energy modelling method for energy efficiency-oriented design

Energy efficiency-oriented design is highly valued in reducing the energy consumption during product use and models for characterizing energy consumption are widely regarded as essential prerequisites of energy efficiency-oriented design. Unfortunately, correlating energy consumption with the products’ design features during the design process is a difficult task. To address this challenge, this paper uses the Function-Behaviour-Structure (FBS) ontology as a bridge to link design features and energy consumption throughout the design process and proposes a FBS-based energy modelling method. This method divides the energy modelling process into two steps. The first is to identify the required energy information and characteristics from available data on the design. The second step is to arrange the obtained information in a logical order to create energy models. Two tools, namely the modified FBS framework and the energy flow diagram, are introduced to aid designers in respectively dealing with the two energy modelling steps. To demonstrate this method, a case study considering mechanical linkage servo press is carried out.

A design approach for safety based on Product-Service Systems and Function–Behavior–Structure

Design for human safety is a complex issue because of the variability of human activities, machines and their environment as well as the variability of possible interactions between these components. The work situation is comprised of the means and the person(s) who act to carry out task(s) in a working environment in accordance with the conditions set for carrying out the task(s). The work situation can generate the hazardous conditions and undesirables events lead to harm. This paper deals with the work situation identifying and analyzing during design to improve safety. Product-Service System (PSS), which is an integrated combination of products and services that shift from product and service systems to Product-Service Systems has been used. The Function–Behavior–Structure (FBS), which covers behavior, is considered to include product and its utilization. The interaction between PSS and FBS, proposed in present paper, allows considering product behaviors and its interaction with service activities. This allows to distinguish the realization of functions by a product part, a service part or a combination of both. The analysis of this interaction is helpful for work situation analysis. Product and service behaviors modeling also are proposed in order to help this analysis. The applicability of the proposed approach is demonstrated through the application to the Power Take-Off (PTO) drive shaft.

A study on the Requirements to Support the Accurate Prediction of Engineering Change Propagation

ABSTRACTThis paper builds on previous work in the area of design representation to identify the types of modeling information required to support the accurate prediction of engineering change propagation during the design of complex engineering systems. It uses the Function–Behavior–Structure (FBS) framework as a basis to examine how engineering changes can occur and how they may subsequently propagate. It was revealed that the relationship between change requirements and product components, the functional dependencies between product components, the behavioral dependencies between product components, and the structural dependencies between product components are all essential modeling information that need to be considered to fully describe the propagation of engineering changes. The essential modeling information identified can serve as modeling requirements to support the development of change prediction methods. In this work, three example design methods were discussed to examine the feasibility of using the modeling requirements for method evaluation. It was concluded that the level of accuracy achievable depends on the design context and hence a direct comparison between methods developed for different design contexts may not be meaningful. This suggests that accuracy should not be used as the sole criterion to evaluate change prediction methods.

Can Pahl and Beitz’ systematic approach be a predictive model of designing?

Pahl and Beitz’ ‘Systematic Approach’ is generally seen as a prescriptive model of designing based on observations of professional design practice. In this paper, we examine whether this model can be used as a predictive model. This is done by testing its predictive capacity for the design behaviour of students that are formally taught design and design methods. The behavioural observations used in this study are based on protocols of 15 design sessions involving mechanical engineering students after their first year of design education and 31 design sessions of the students using various concept generation methods. The design protocols and the Systematic Approach are coded uniformly using the Function–Behaviour–Structure (FBS) design issue schema. Cumulative occurrence analysis is used to derive qualitative and quantitative measures as a basis for comparison between the Systematic Approach’s prediction and the students’ design behaviour. The results indicate that the Systematic Approach can predict some but not all of students’ design issue behaviour.

Research on the propagation path of function change in product conceptual design

Product design was a repetitive process. Given that product structure was closely related to functions, function change was vital to the final design and core of design change. The effect of predicting function change during conceptual design on the final product structure was important to improve the design quality. A model was proposed to predict the propagation path of function change during conceptual design. Based on function–behavior relationship and behavior–structure relationship, a function–behavior–structure model of product design history was established. The propagation scope of function change in the functional layer was determined by analyzing input/output streams of functions. Function change was mapped onto behavior structure. The propagation scope of behavior change in the behavior layer was determined by analyzing the input/output state consistency of behavior. The changed parts were identified through behavior–structure relationship. Finally, the propagation path of function change was represented completely. The proposed propagation model of function change can provide a reference for quick product design. The feasibility and validity of the proposed model were verified through a case study, particularly the function change of monocular ice crusher.

Diagrammatic Modeling Language for Conceptual Design of Technical Systems: a Way to Achieve Creativity

The product development process begins with the phase of problem definition and requirements, and this is followed by the phase of conceptual design, which is the subject matter of this paper, with a focus on the creation of a design diagrammatic description. The conceptual design phase is acknowledged, as the particularly critical and significant decisions made in this phase affect all subsequent design phases. The purpose of the work reported in this paper is to introduce a flow-based diagrammatic language as an alternative approach to a currently dominant framework in the area that is based on the framework of the function-behavior-structure (FBS). The paper adopts the method of re-designing some examples from the object-oriented conceptual design in the context FBS, using the proposed diagrammatic modeling language. Accordingly, a major contribution here is showing the capability of this language in playing a pivotal role in the conceptual design domain. Additionally, we claim that the flows in the proposed representation could trigger design creativity as an appropriate searching space for determining the decomposition of the design.

Characterizing Design Cognition of High School Students: Initial Analyses Comparing those With and Without Pre-Engineering Experiences

Reported in this article are initial results from of a longitudinal study to characterize the design cognition and cognitive design styles of high school students with and without pre-engineering course experience over a 2-year period, and to compare them with undergraduate engineering students. The research followed a verbal protocol analysis based on the function– behavior–structure (FBS) ontology, which employs a task-independent approach that is distinct from a task-based or an ad hoc approach. This approach to protocol analysis is applicable across any process-based view of designing and generates results based on a common comparative measure independent of the design task. In this article, Year 1 results are presented comparing only students in their junior year of high school who had formal pre-engineering course experience (experiment group) with those who did not have formal pre-engineering course experience (control group). Specifically, data collected from design sessions were analyzed for comparison of design issues and processes between experiment and control groups, respectively. Results from analysis of Year 1 data did not reveal any significant differences between the experiment and control groups in engineering design cognition. Based on these results, one would conclude that students with pre-engineering course experience do not demonstrate a stronger focus on the process of producing design solutions than do students without such experience. Although analysis of demographic data from high school participants indicates some degree of common prior preengineering experiences, it did not provide a sufficient explanation for why no significant differences in engineering design thinking were found between these groups. The researchers anticipate that Year 2 data will indicate that as the preengineering students continue engaging in formal engineering design experiences during their final year of high school, some degree of difference in design cognition will be demonstrated.

A method of implementing formalized multidisciplinary collaboration in product conceptual design process

Modern product design can be considered as a process, which involves intensive iteration, complex reasoning, and mutual cooperation among the design groups in different disciplinary areas. In order to meet the requirements of modern products on multidisciplinary collaboration, the traditional method, where the product conceptual design is usually solved only within a single discipline, should be improved. Based on the classic function–behavior–structure model of product conceptual design, this paper studied the collaborative mechanism of functions, behaviors and structures, and proposed a new method/system of implementing formalized multidisciplinary collaboration in the product conceptual design process. In this method, the model/system of conceptual design process with multidisciplinary collaboration was established first, and three collaboration mechanisms were developed. After the coupling relationship among the design sub-states and the disciplinary classification characteristics of the design sub-states were expressed by the mathematical ways, the particle swarm algorithm was applied for the discipline planning, next the solving process for multidisciplinary collaboration were proposed. Finally, the conceptual design process of a stylus printer was used to illustrate the application of the proposed method.

Research on new creative conceptual design system using adapted case-based reasoning technique

AbstractCreative conceptual design requires significant previous design knowledge. Case-based reasoning enables learning from previous design experience and has a great potential in supporting creative conceptual design by means of seeking to retrieve, reuse, and revise most appropriate cases to generate inspired solutions. However, traditional case-based reasoning based creative conceptual design models focus on design strategies research, pay little attention to defining a consistent knowledge representation model, and neglect the research to make various types of knowledge retrieval tractable. Faced with such drawbacks, the expected design knowledge cannot be retrieved properly, especially in cases where multidisciplinary knowledge is concerned or exact query terms are absent. In order to solve these issues, this paper presents a combined approach to support creative conceptual design process. First, function–behavior–structure knowledge cell is introduced as a unified consistent design knowledge representation model. Second, a hybrid similarity measure is proposed to increase the overall possibility of obtaining useful design knowledge by considering semantic understanding ability. Third, an intelligent creative conceptual design system has been developed with a case study of a novel insulin pump design to demonstrate its usage, and two experiments are conducted to evaluate the performance of the proposed approach. The results show that the proposed approach outperforms other case-based reasoning based creative conceptual design models.

Prototyping with your hands: the many roles of gesture in the communication of design concepts

ABSTRACTThere is an on-going focus exploring the use of gesture in design situations; however, there are still significant questions as to how this is related to the understanding and communication of design concepts. This work explores the use of gesture through observing and video-coding four teams of engineering graduates during an ideation session. This was used to detail the relationship between the function behaviour structure elements and individual gestures as well as to identify archetypal gesture sequences – compound reflective, compound directed one-way, mirroring, and modification. Gesture sequences occurred at critical periods during the design session, such as idea evolution and developing shared understanding. They are used to act out design concepts, repeat and learn from sequences, and establish shared understanding. Finally, a number of implications are identified for both researchers and those seeking to support practice.

Understanding Creative Design Processes by Integrating Sketching and CAD Modelling Design Environments: A Preliminary Protocol Result from Architectural Designers

This paper presents the results of a preliminary protocol study of the cognitive behaviour of architectural designers during the design process. The aim is to better understand the similarities and differences in cognitive behaviour using Sequential Mixed Media (SMM) and Alternative Mixed Media (AMM) approaches, and how switching between media may impact on design processes. Two participants with at least one-year’s professional design experience and a Bachelor of Design degree, and competence in both sketching and computer-aid design (CAD) modelling participated in the study. Video recordings of participants working on different projects were coded using the Function-Behaviour-Structure (FBS) coding scheme. Participants were also interviewed and their explanations about their switching behaviours were categorised into three types: S→C, S/C↹R and C→S. Preliminary results indicate that switching between media may influence how designers identify problems and develop solutions. In particular, two design issues were identified. These relate to the FBS coding scheme, where structure (S) and behaviour derived from structure (Bs), change to documentation (D) after switching from sketching to CAD modelling (S→C). These switches make it possible for designers to integrate both approaches into one design medium and facilitate their design processes in AMM design environments.

Software engineering process theory: A multi-method comparison of Sensemaking–Coevolution–Implementation Theory and Function–Behavior–Structure Theory

ContextSoftware engineering has experienced increased calls for attention to theory, including process theory and general theory. However, few process theories or potential general theories have been proposed and little empirical evaluation has been attempted. ObjectiveThe purpose of this paper is to empirically evaluate two previously untested software development process theories – Sensemaking–Coevolution–Implementation Theory (SCI) and the Function–Behavior–Structure Framework (FBS). MethodA survey of more than 1300 software developers is combined with four longitudinal, positivist case studies to achieve a simultaneously broad and deep empirical evaluation. Instrument development, statistical analysis of questionnaire data, case data analysis using a closed-ended, a priori coding scheme and data triangulation are described. ResultsCase data analysis strongly supports SCI, as does analysis of questionnaire response distributions (p<0.001; chi-square goodness of fit test). Furthermore, case-questionnaire triangulation found no evidence that support for SCI varied by participants’ gender, education, experience, nationality or the size or nature of their projects. ConclusionsSCI is supported. No evidence of an FBS subculture was found. This suggests that instead of iterating between weakly-coupled phases (analysis, design, coding, testing), it is more accurate and useful to conceptualize development as ad hoc oscillation between making sense of the project context (Sensemaking), simultaneously improving mental representations of the context and design space (Coevolution) and constructing, debugging and deploying software artifacts (Implementation).

Extending the situated function–behaviour–structure framework to human–machine interaction

Despite the increasing importance of human–machine interaction (HMI) in design, there are not reference models defining and describing design activities where users are directly involved in the team. Some years ago, the situated function–behaviour–structure (FBS) framework was developed to model traditional engineering design processes but these mainly focus on technological matters and users are not directly addressed. The goal of this research is to extend this framework to cover several aspects of the HMI field. To achieve this goal, an existing design aid named interaction design integrated method is exploited. The design activities based on this aid are mapped onto the situated FBS framework to highlight possible lacks or misalignment. The outcomes are used to find where and how to intervene to extend the framework. The mapping highlighted six criticalities and their analysis allowed for adding the users as a new agent in the design process, as well as for introducing new variables and design activities referred to this new actor.

Is designing independent of domain? Comparing models of engineering, software and service design

This paper presents a quantitative method for analysing process models of designing independently of the specific design domain. The method uses the situated function–behaviour–structure framework as the basis for a simulation model of a designer acting according to these models. The results of these simulations are sequences of design issues that are analysed using cumulative occurrence graphs with associated quantitative measures. The paper illustrates the approach by analysing and comparing three models of designing from different domains: Pahl and Beitz’ model of engineering design, the rational unified process of software design and a model of design for six sigma in service design. The quantitative results indicate some commonalities across the different models. These commonalities are related to the start of cognitive effort spent on design issues, the continuity of the cognitive effort throughout the design process and the constancy of the speed with which design issues are generated.

Approximate Life Cycle Assessment via Case-Based Reasoning for Eco-Design

Life cycle assessment (LCA) is a fundamental tool used in eco-design. However, it can be costly and resource intensive. We take steps toward the automation of the inventory and impact analyses stages of LCA via the proposal and development of a case-based reasoning (CBR) procedure to estimate the ecological effects of a product. The case memory in CBR, which contains representations and ecological effects of known products, is organized using an extension of the function-behavior-structure (FBS) representation for products. The extension includes ecological characteristics and values. We develop similarity metrics to measure the distance between cases in the case memory and the new product. The $k$ -medoids algorithm is used to cluster the case memory, our metrics enable cluster retrieval and case selection, and multiple linear regression analysis is employed for adaptation. Using a database of 100 fans, we test the accuracy of the proposed approach on a cross flow fan not in the database. The method gives ecological effect estimates within 3% of the true values when there are similar fans in the retrieved cluster and about 7% when the retrieved cluster does not contain similar fans.

Industrial evaluation of FBS Linkage – a method to support engineering change management

Engineering changes (ECs) are raised throughout the product life cycle and their management can determine the commercial success of products. A well-established method to support engineering change management (ECM) is the change prediction method (CPM). The function–behaviour–structure (FBS) linkage method enhances CPM with an FBS scheme and allows more detailed modelling and analysis of ECs. The goal of this paper is to provide an industrial evaluation of the FBS Linkage method. For that purpose, we provide first an overview of the FBS Linkage method, before applying it to a diesel engine design and evaluating it by a group of 10 experienced engineers from the diesel engine manufacturer. Overall, the engineers favoured the FBS Linkage method and ranked it on average 3.7 out of 5.0 against a set of 25 different requirements for ECM methods. The evaluation underlines the benefits of the method in terms of a systematic way for capturing, explaining and transferring knowledge about the product and effects of ECs on it. Identified improvement areas include more guidelines on the scope of the method, reduction of the effort required to build FBS Linkage models, and an integration of the method into other applied systems.

Computer-based creativity enhanced conceptual design model for non-routine design of mechanical systems

Computer-based conceptual design for routine design has made great strides, yet non-routine design has not been given due attention, and it is still poorly automated. Considering that the function-behavior-structure(FBS) model is widely used for modeling the conceptual design process, a computer-based creativity enhanced conceptual design model(CECD) for non-routine design of mechanical systems is presented. In the model, the leaf functions in the FBS model are decomposed into and represented with fine-grain basic operation actions(BOA), and the corresponding BOA set in the function domain is then constructed. Choosing building blocks from the database, and expressing their multiple functions with BOAs, the BOA set in the structure domain is formed. Through rule-based dynamic partition of the BOA set in the function domain, many variants of regenerated functional schemes are generated. For enhancing the capability to introduce new design variables into the conceptual design process, and dig out more innovative physical structure schemes, the indirect function-structure matching strategy based on reconstructing the combined structure schemes is adopted. By adjusting the tightness of the partition rules and the granularity of the divided BOA subsets, and making full use of the main function and secondary functions of each basic structure in the process of reconstructing of the physical structures, new design variables and variants are introduced into the physical structure scheme reconstructing process, and a great number of simpler physical structure schemes to accomplish the overall function organically are figured out. The creativity enhanced conceptual design model presented has a dominant capability in introducing new deign variables in function domain and digging out simpler physical structures to accomplish the overall function, therefore it can be utilized to solve non-routine conceptual design problem.

FBS Linkage ontology and technique to support engineering change management

Engineering changes are essential for any product development, and their management has become a crucial discipline. Research in engineering change management has brought about some methods and tools to support dealing with changes. This work extends the change prediction method through incorporation of a function–behaviour–structure (FBS) scheme. These additional levels of detail provide the rationales for change propagation and allow a more proactive management of changes. First, we develop the ontology of this method based on a comprehensive comparison of three seminal functional reasoning schemes. Then, we demonstrate the FBS Linkage technique by applying it to a diesel engine. Finally, we evaluate the method.

An FTPBM Model for Conceptual Design of Mechanical Execution System

Mechanical execution system is an important part of mechanical system that contributes to the delivery of system function. There is currently no conceptual design model that is specifically for the conceptual design of mechanical execution system. Based on the FBS (Function-Behavior-Structure) model, this paper investigates the characteristics of the conceptual design process of mechanical execution system, and subsequently proposed an FTPBM (Function-Technology-Process action-Motion behavior-Mechanism) model for its conceptual design. The model includes a functional prototype and six steps of design procedure as well as a number of design synthesis strategies and methods. A design case of press machine is also studied, which demonstrates the proposed model to be not only practicable, but also improve the designers innovation capability.