In the field of individualized medical implants for bone replacesment, additive manufacturing offers far-reaching advantages for bridging bone defects and supporting the production of natural form and function. The article uses the example of a large, customized cranial implant to show the challenges of manufacturing with osteoinductive bone cements. The process is shown, starting with planning and design, through to functional integration using adapted manufacturing strategies to create defined porosity.

The use of design methods across multiple design phases of the product development process often leads to inconsistency, the loss of transparency, and the rejection of design methods by practitioners. The authors of this work intend to develop a central modelling approach that supports consistency, based on the integrated function modelling (IFM) framework. Therefore, various design methods from the literature were examined for their techniques and content to identify indicators for supporting consistency. The results led to an enhancement of the IFM framework.

Decisions made in the concept generation phase have a significant effect on the product. While product- related risks typically can be considered in the early stages of design, risks such as supply chain and manufacturing methods are rarely easy to account for in early phases. This is because the currently available methods require mature data, which may not be available during concept generation. In this paper, we propose an approach to address this. First, the product and the non-product (manufacturing and/or supply chain) attributes are modelled using the enhanced function means (EF-M) modelling method. The EF-M method provides the opportunity to model alternative solutions-set for functions. Dependencies are then mapped within the product and the manufacturing models, and also in between them. An automatic combinatorial method of concept generation is employed where each generated instance is a design concept-manufacturing method pair. A risk propagation algorithm is then used to assess the risks of all the generated alternatives.

The transmission of information between requirements modelling and function modelling in the product development process often appears challenging because of multiple used models and different terminology of specific disciplines. The integrated function modelling (IFM) framework is used for functional analysis of technical moderate complex systems and supports cross-disciplinary modelling and communication in the design team. To improve the applicability of this method and its supporting purpose in the modelling process, the authors combined requirements as an additional entity with the existing entities of this method. Furthermore, the extended framework has been used to visualise the procedure with this approach as an example. The outlook provides the potential for further development of the method.

Lattice structures are lightweight and possess other unique mechanical and physical properties. Additive manufacturing techniques are often used to produce these structures. Additive manufacturing provides manufacturing freedom that significantly surpasses the one provided by conventional subtractive manufacturing. However, a gap exists between the manufacturing freedom and the geometric modelling freedom in additive manufacturing: it can be extremely challenging to model the designed part because of its high geometric complexity, such as heterogeneous lattice structures. While several tools on the market allow geometric modelling of such structures available on the market, the customization of lattice parameters can still be significantly improved. Moreover, no open-source tools exist to address this issue or to model lattice structures in general. This work presents a novel open-source library for the geometric modelling of lattice structures with customized parameters. The parameter customization is enabled with the function representation approach.

In the last few years, the growing need of highly reliable and time-effective strategies to perform preliminary design of complex systems has led industries to adopt the Model Based System Engineering (MBSE) approach. In MBSE, systems are split into multiple sub-systems and the relevant physical phenomena are described via analytical or numerical models. When a significant number of design variables are to be considered, a smart approach to reduce the number of analyses to perform would be to make use of the Global Sensitivity Analysis (GSA) to higlight those variables that have a more significant influence on the system output. Moreover, an even more significant reduction of computational cost to perform the GSA can be achieved if the complex system modelled via the MBSE approach is exported under the Functional Mock-Up Interface (FMI) norm. In this context, this paper proposes an original approach to address the study of two constructive solutions of an acceleration measuring device typically used on airbags for which the use of a new solution characterized by a porous material is compared with a classical one.

Due to an expanding number of mechatronic functionalities in modern technical products, the proportion of software and electronic components is also increasing. As a result, the products are developed by different engineering domains in complex development processes. To handle the growing complexity, Systems Engineering (SE) is increasingly important for development organizations of enterprises. System Engineering (SE) is understood as an approach to network the individual engineering domains and shall lead to a collaborative development of complex systems. Model-Based System Engineering (MBSE) expands SE by using common models and software tools to describe und visualize the systems. However, MBSE is not widely established in enterprises today. On the one hand, the introduction requires a distinct and consistent system understanding and collaborative way of working. On the other hand, the application of the existing tools requires extensive tool competencies due to many possible functions and features. Therefore, this paper presents a concept and a software based tool for a lean implementation of SE/MBSE to support the collaborative development of complex technical systems in small and medium-sized enterprieses.

Model-Based Systems Engineering (MBSE) is increasingly used across industries for the integrated modelling of complex systems to support model-based development and provide enhanced traceability between requirements and verification and validation of the system. This paper seeks to strengthen the function modelling methodology in MBSE by introducing an approach based on flow heuristics guided by the System State Flow Diagram schema. This provides function representations with an enhanced integrity in MBSE facilitating the solution-agnostic architecture modelling, and supports integrated simulation and function failure reasoning based on MBSE. The approach is illustrated with a case study of an electric bicycle implemented in the MathWorks System Composer environment.

This paper presents an evaluation study for the System State Flow Diagram function modeling framework based on a large-scale study with an automotive OEM. Technical reports are used to evaluate the usage of the framework within the organization. The paper also introduces a list of the type of problems that engineers are interested in in practical function modelling. The findings suggest that there is a widespread uptake of the framework across the organization and it supports the usage of relevant key engineering tools within the context of a broader model-based Failure Mode Analysis methodology.

The main focus of this paper is the exploration of fault accommodation possibilities in the context of function development. Faults occur in complex technical systems and may lead, if no accommodation entities or processes are present, to catastrophic failure. Several entities and processes exist and are applied, but mainly on the concrete levels. Faults very often concern more than one physical domain and accommodation possibilities are present in many physical or even non-physical domains. This paper explores this specific challenge and proposes an initial collection of countermeasures.

This paper investigates the use of ANNs to model human behaviour in design by comparing the predictive capability of ANNs and engineering students. Function structure models of 15 products are used as input for prediction. The type of information provided varied between topology and vocabulary. Analysis of prediction accuracy showed that ANNs perform comparably to students. However, students are more precise with their predictions. Finally, limitations and future work are discussed, with research questions presented for subsequent research.

This paper presents the re-design approach of an urban motorcycle helmet to prevent users bypassing the strap fastening system. Related studies show that although a full-face helmet provides the maximum protection to a rider, in practice, full-face helmeted riders in urban traffic tend to improperly fasten it. On that notion, the design goal was to conceive a helmet that combines the advantages of different helmet types while responding to urban driving needs. During design ideation possible solutions were examined focusing on different ways of accessing and fixating the helmet on a rider’s head, without using a strap fastening system. Preliminary concept development produced three design concepts, that were evaluated using two sets of prototypes: (a) the 3D printing method under a 1:2 scale was used to detect any design faults, while the 3D modeled concepts were evaluated in four different crash impacts regarding total deformation and von-Mises stress, and (b) 1:1 models of the three concepts were used by experienced riders to assess possible usability issues during helmet placement/removal. Results of the two-phase evaluation of the three concepts and design issues for further development of them are discussed.

The design of ITER, a large-scale nuclear fusion reactor, is intertwined with profound research and development efforts. Tough problems call for novel solutions, but the low maturity of those solutions can lead to unexpected problems. If designers keep solving such emergent problems in iterative design cycles, the complexity of the resulting design is bound to increase. Instead, we want to show designers the sources of emergent design problems, so they may be dealt with more effectively. We propose to model the interplay between multiple problems and solutions in a problem network. Each problem and solution is then connected to a dynamically changing engineering model, a graph of physical components. By analysing the problem network and the engineering model, we can (1) derive which problem has emerged from which solution and (2) compute the contribution of each design effort to the complexity of the evolving engineering model. The method is demonstrated for a sequence of problems and solutions that characterized the early design stage of an optical subsystem of ITER.

There is an inherent tension between functional descriptions of products and structural descriptions. Traditionally system architecture combine the two, by mapping system elements to functions. In this process fundamental decisions about the embodiment of a product are often taken without proper scrutiny. Axiomatic design advocates a zigzag between functional decomposition and system break down. While this approach makes sense for ab initio design these are rare and most products are developed incrementally., This paper takes up the idea of a functional reference architecture.

Conventional functional modelling advocates a hierarchical decomposition into sub function. By contrast FRAs decompose function into function chain, i.e., dependent sequences of sub function required to carry out an overall function. This allows the identification of common sub-functions in different chains, and thereby generates a lattice structure of functions rather than a tree. This enables a detailed but solution neutral description of the product.

This concept has attracted interest in industry but does not have many tools and methods to develop FRA. The paper discusses some of the areas that require research

Patent analysis is a popular topic of research. However, designers do not engage with patents in the early design stage, as patents are time-consuming to read and understand due to their intricate structure and the legal terminologies used. Manually produced graphical representations of patent working principles for improving designers’ awareness of prior art have been demonstrated in previous research. In this paper, an automated approach is presented, utilising Natural Language Processing (NLP) techniques to identify the invention working principle from the patent independent claims and produce a visualisation. The outcomes of this automated approach are compared with previous manually produced examples. The results indicate over 40% match between the automatic and manual approach, which is a good basis for further development. The comparison suggests that the automated approach works well for features and relationships that are expressed explicitly and consistently but begin to lose accuracy when applied to complex sentences. The comparison also suggests that the accuracy of the proposed automated approach can be improved by using a trained part-of-speech (POS) tagger, improved parsing grammar and an ontology.

Comparing the propensity for risk in concepts with little commonality, such as different working principles, different number of functions and components, is challenging to achieve in a systematic and traceable manner. This paper builds on the Function Integrity Diagnosis and Documentation method to introduce a Function Integrity indicator as a means to quantitatively compare dissimilar design concepts based on risk assessment. The proposed indicator is intended to support designers converge on a suitable design concept based on considerations of risk to concept functions.

The multidisciplinary nature and lack of comprehensive ‘materials-product-manufacturing’ knowledge of Functionally Graded Additive Manufacturing (FGAM) require training to support the future Additive Manufacturing experts. INEX-ADAM, an EU funded project is building a transnational platform to promote FGAM. Brunel University London conducted two-day workshop on FGAM at the University of Zagreb in Croatia with academics and industry professionals. The workshop will strengthen the research capabilities to harness the potential of the FGAM and mitigate the constraints to industrial applications.

Although well researched and praised in academic publications, function modelling (FM) does not have gained much traction in industrial application. To investigate into possible reasons for this, this publication researches literature of nine different projects where enhanced function-means modelling has been applied. The projects are analysed for their purpose of FM-use, applied benefits and discovered challenges of the FM approach. From this, the main challenges for FM application are the abstraction level of the modelling language as well as the lack of an interface to CAD modelling.

The digitalization of the Industry is one of the megatrends taking place, but many companies struggle to follow this trend. The main reason is the absence of simple solutions for the integration of sensory functions, which are applicable to the existing system. Therefore, this paper discusses the aspects of simplicity in the context of integrating sensory functions into existing systems, to support the development of digitalized products.

Two general requirements can be formulated for a solution to be applicable simple: The first requirement is affected by the product structure. The solution must affect the least possible amount of modules and must not interfere with the interfaces of the modular platform. The second requirement is affected by the effort to model the behaviour of the desired information and the possible data a sensory function is delivering. The effort to develop a reliable solution has to be compared with the commercial potential of the solution.

To consider the mentioned requirements, the paper explains three approaches to assess the simplicity of solutions on an example of the desired monitoring of the functions of a rotary plug valve.

The aerospace industry experiences a considerable growth in product development costs. Many research works aim at identifying evolution laws characterizing this large-scale phenomenon and at developing design strategies which could help mitigate it. This paper aims to clarify the evolution dynamics governing this phenomenon by studying how the products delivered by these costly projects evolve with time. Increasing complexity is often held responsible for surging costs. If complexity is generally defined as the price to be paid for improving product functionalities, it is rarely specified whether the improvement affects existing functionalities or involves new ones. We aim to identify the patterns of cost growth which can be associated with phenomena of existing functionalities upgrade and new functionalities introduction, and to identify the associated design capabilities that designers need to deploy in order to keep product change and cost growth under control. To that end, we introduce a model which generates curves, each of which featuring a trend of cost growth, specific to a scenario of product evolution and being interpretable as a signature of a strategy used by designers.