Additive manufacturing (AM) is a versatile technology that could add flexibility in manufacturing processes, whether implemented alone or along other technologies. This technology enables on-demand production and decentralized production networks, as production facilities can be located around the world to manufacture products closer to the final consumer (decentralized manufacturing). However, the wide adoption of additive manufacturing technologies is hindered by the lack of experience on its implementation, the lack of repeatability among different manufacturers and a lack of integrated production systems. The later, hinders the traceability and quality assurance of printed components and limits the understanding and data generation of the AM processes and parameters. In this article, a design strategy is proposed to integrate the different phases of the development process into a model-based design platform for decentralized manufacturing. This platform is aimed at facilitating data traceability and product repeatability among different AM machines. The strategy is illustrated with a case study where a car steering knuckle is manufactured in three different facilities in Sweden and Italy.

The current ways of coping with uncertainty such as changes during product design or use have been through methods such as easy restructuring (e.g., modularity with buffer in interface definition), by overdesign and so on. The present investments on maintaining products in the economy for “as long as possible” is challenging these strategies from a cost and environmental perspective. Moreover, these strategies often lead to highly overdesigned products. An alternative strategy is to introduce features in a design, called “resilient objects”, which are able to absorb such uncertainties without wasteful overdesign of other parts. By applying a ‘text-mining’ approach on patents, this paper has identified 5,552 candidates for such resilient objects that can be recombined and inserted in regions of the product that are likely to be most affected by current and future uncertainties. The application of resilient objects is demonstrated on a case study (a cooling system for battery electric vehicles). The case study highlights the ability of these objects to 1) significantly increase protection against uncertainties without the need for restructuring, 2 ) reduce the risk for overdesign and 3) dampen effects of change propagation.

The Covid-19 outbreak forced many universities across the world to transition from a traditional or blended format to fully online education. This paper presents a case study on the transition to an online education format for a circular design course. Both quantitative and qualitative data were collected through a survey with 26 students and interviews with six course teachers. The findings revealed that students preferred the on-campus versions over the online course components. They indicated the perceived lack of motivation, lack of sense of community, and a high workload as influencing factors. Teachers indicated the lack of connection with students as a drawback to online education but identified advantages to their teaching and the student’s learning experience. Suggestions for addressing an optimal blended course format are provided.

Customer preference modeling provides quantitative assessment of the effects of engineering design attributes on customers’ choices. Utility-based approaches, such as discrete choice model (DCM), and network analysis approaches, such as exponential random graph model (ERGM), have been developed for customer preference modeling. However, no studies have compared these two approaches. Our objective is to identify the distinctions and connections between these two approaches based on both the theoretical foundation and the empirical evidence. Using the vehicle preference modeling as an example, our study shows that when network structure effects are not considered, results from ERGM are consistent with DCM in most of the test cases. However, in one case where customers have varying choice set with multiple alternatives, inconsistencies are observed, possibly due to the discrepancies of the two models in taking different information when calculating choice probabilities. The insights will lead to valuable guidance for choosing the technique for customer preference modeling and co- developing the two frameworks to support engineering design.

This paper presents an EEG (Electroencephalography) study that explores the correlation between the EEG variation across design stages and the quality of the design outcomes. The brain activations of 33 volunteers with engineering backgrounds were recorded while performing a design task using a morphological table to develop an amphibious bike. The EEG variations from the analysing/selecting stage to the illustrating stage were analysed based on the EEG frequency band and channel sets. A significant correlation between the detail level of the design outcome and the power variation mode was observed in theta, alpha and gamma bands, each involving different channel sets. Compared to the assessment results from two evaluators, using EEG variations as a proxy of the detail level of the design outcome could reach a maximum accuracy of 0.727, precision of 0.765, and recall of 0.889. These results also provide suggestions on the selection of the frequency bands and channel sets to achieve better prediction performance according to each metric.

The increasing need to motivate and engage participants in the co-design has led to the trend of employing game elements in the early phase of the design process to facilitate the activities. However, most have described the gamified co-design by its methods, purposes, and functions. How games theoretically contribute to achieving those goals is still uncovered. This research aims to bridge this theoretical-practical gap by first defining the game principles from the literature. Then investigate how those principles manifested in two case studies with detailed game elements. Finally, we present a framework that links the game principles and purposes/functions by reflecting the cases.

Within the scope of Design for Sustainable Behaviour, the connection between behavioural change strategies and design idea generation has received limited attention. This paper highlights metaphorical thinking in product design to stimulate sustainable behaviour. In particular, the current study proposes a metaphor-based design method to guide designers on how to associate product features with behavioural and experiential cues through metaphors. We next report two design cases to evaluate this method. In the end, the shortcomings of current research and future developments are also discussed.

Sketching ideas and building physical prototypes are common in early stage product development. They are used for learning, testing ideas, proving concepts and sharing knowledge. Laser cutting is a popular tool for making physical prototypes due to its accuracy, robustness and speed. Computer aided design and vector graphics software are the main tools used for designing parts for laser cutting. Several sketch- based interfaces have been developed to support the process, using tools such as stylus pens with intuitive sketch-like commands.

A proof-of-concept prototype for capturing a hand drawn sketch and converting it to a laser cuttable file has been developed. In this pilot study we attempt to discover when drawing design by hand on paper can be better or more efficient than conventional methods, for developing physical prototypes with laser cutting in the context of early stage product development. This includes testing the accuracy of the tool, a pilot experiment comparing drawing speed and accuracy, example use cases utilizing pencil and paper, and a simple design challenge experiment.

Established companies turn to new ventures for bolstering exploration activities, but we know relatively little of the product development processes of startups and new ventures and how different stakeholders are utilized in these. The current study investigated the product development activities and experiments of eight Finnish food and beverage ventures in a multiple case study based on 22 interviews. How the developed products fit into the existing portfolio and experience of the ventures seemed to define their enacted development process. Internal experimentation was a constant feature, although the type of experiments varied between different phases of the development process. External-facing experiments were less frequent and more for validation than concept generation. On the other hand, they also carried important market creation functionalities. The results suggest that more nuanced terminology around experimentation would be useful to determine what type of experiments serve different goals in the development process.

The breadth of media and approaches used when prototyping are vast, with each holding inherent properties that vary their suitability for a given prototyping activity.

While several have established classifications of types and purposes of prototypes, there is little by way of guidance for designers on how select and strategise prototyping given their activity needs, or how the prototype chosen may influence their process, success or efficiency.

This paper presents nine affordances of prototypes derived from literature, together characterising the properties of prototyping media or approaches that affect their suitability across prototyping activities.

The affordances are illustrated through application to physical and digital classes of prototypes and four real prototype cases, showing descriptive capability, inherent differences between the media, and enabling direct and consistent comparison.

By mapping affordances across many media and approaches, this work enables better method selection to align with activity needs, better description and comparison of media and approaches, and the ability the broadly interrogate and direct future development of prototyping technologies.

Structuring the early design phase of automotive systems is an important part of efficient and successful development processes. Today, safety considerations (e.g., the safety life cycle of ISO 26262) significantly affect the course of development. Preliminary designs are expressed in functional system architectures, which are required to form safety concepts. Thus, mapping tasks and work products to a reference process during early design stages is an important part of structuring the system development. This contribution describes the systematic creation and notation of the functional safety concept within the concept phase of development of an unmanned protective vehicle within the research project aFAS. Different stages of preliminary design and dependencies between them are displayed by the work products created and used. The full set of functional safety requirements and an excerpt of the safety argument structure of the SAE level 4 application are presented.

A central part of the design process is collaboration, harnessing specialist expertise often in meetings. We understand relatively little about how meetings serve teams of designers and their work and this study uses soft systems methodology to attempt to create structures that describe and explain meetings. The results suggest extension of the boundary of interest and suggest a conceptual framework which reveals some under-addressed stages and activities which may help designers improve their meetings.

Product-service systems (PSS) are being increasingly employed as opportunities to keep innovating. The design of PSS value propositions should focus on the value visualization for stakeholders. However, the PSS representations are still oriented to the customer’ perspective and focus on a process or technological role. This study aims to represent the PSS value proposition in a structured-diagram adapted from the journey map method in combination with the use of the elements of value. A case research was conducted with a high-tech agricultural start-up for representing its value proposition by following a process founded in the practices of journey mapping. Qualitative data analysis was employed to associate the elements of value with the solution, and to verify the consistency of the results. The representation enables the visualization of the stakeholders’ perception regarding the content of the solution as well as the potential value that may be related to it. The experience-centric perspective derived from the journey map associated with the value-related information provides a richer view of the PSS value proposition, which can lead to reflections regarding the solution.

Aircraft cabin monuments must be optimized in terms of lightweight design, cost structure and variance. Model-based approaches support the aircraft data and help to modify them consistently during further development. In this paper, a holistic methodological approach for product families of aircraft cabin development is shown, which integrates lightweight and cost-efficient aspects, in addition to the variance focus. For this purpose, the development of cost-efficient and ligthweight optimized cabin modules is supported in a model-based way.

In industry, there is at once a strong need for innovation and a need to preserve the existing system of production. Thus, although the literature insists on the necessity of the current change toward Industry 4.0, how to implement it remains problematic because the preservation of the factory is at stake. Moreover, the question of the evolution of the system depends on its innovative capability, but it is difficult to understand how a new rule can be designed and implemented in a factory. This tension between preservation and innovation is often explained in the literature as a process of creative destruction. Looking at the problem from another perspective, this article models the factory as a site of creative heritage, enabling creation within tradition, i.e., creating new rules while preserving the system of rules. Two case studies are presented to illustrate the model. The paper shows that design in the factory relies on the ability to validate solutions. To do so, the design process can explore and give new meaning to the existing rules. The role of innovation management is to choose the degree of revision of the rules and to make it possible.

Function and constraints modelling are implemented to design two gridded ion thrusters for additive manufacturing (AM). One concept takes advantage of AM design freedom, disregarding AM limitations and is not feasible. The other concept considers AM limitations and is manufacturable and feasible. Constraints modelling highlights AM capabilities that can be improved, showing where future investment is needed. Constraints representation can also support the creation of technology development roadmaps able to identify areas of AM technologies that must be improved.

The rise in the number of people living with long-term conditions is precipitating a shift towards the development of wearable technologies that can monitor our health remotely. This shift makes it possible to rethink the healthcare structure towards awareness and proactive prevention instead of treatment through empowering users, e.g. patients for self-management of their health. In a sector towards individual specialization and relying on personal healthcare management, design has a key role in user participation and engagement. This paper reports a co-design study that empowered the participants as designers to design human-centred interventions that foster sun protection behaviour in young men. The findings from this study show the following: 1) sun protection concepts to enhance young men's engagement in sun protection behaviour, 2) the integration of gender-aware design in digital health wearables contributes towards better user engagement in wearable technologies of the future.

Additive manufacturing enables new possibilities for the design of end products. These are rooted in the potentials of the manufacturing technology, such as flexible, tool-free production. These potentials can be used for the economic and flexible production of customized products. To support the use of the potentials, a development method was created which identifies optimization areas within a product. Therefore, the complexity is reduced by using of product functions. Characteristic functions and structural configurations are used to identify optimization areas. This contribution describes the application of the new development method to an existing mechanical transtibial prosthesis. In doing so optimization areas are identified which may make use of the potentials provided by additive manufacturing. One area is the interface between the prosthesis and the ground. By analyzing walking environments and the gait cycle the need for walking assistance on deformable surfaces was identified. Significant improvements were achieved through a functional integrated, additive manufactured foot sleeve.

The success of complex product development projects strongly depends on the clear definition of target factors that allow a reliable statement about the fulfilment of the product requirements. In the context of tolerancing and robust design, Key Characteristics (KCs) have been established for this purpose and form the basis for all downstream activities. In order to integrate the activities related to the KC definition into product development as early as possible, the often vaguely formulated requirements must be translated into quantifiable KCs. However, this is primarily a manual process, so the results strongly depend on the experience of the design engineer.

In order to overcome this problem, a novel computer-aided approach is presented, which automatically derives associated functions and KCs already during the definition of product requirements. The approach uses natural language processing and formalized design knowledge to extract and provide implicit information from the requirements. This leads to a clear definition of the requirements and KCs and thus creates a founded basis for robustness evaluation at the beginning of the concept design stage. The approach is exemplarily applied to a window lifter.

Various aspects of the design process often lead to stress. This study used pre- and post-task surveys to gather information regarding the designer's cognitive experience, physiological response, and perceived sources of stress during concept generation, concept selection, and prototyping. Results confirmed that design is highly cognitive, and that mental stress is present. Variability in the results also suggests that a physiological stress component might be present. Additionally, perceived sources of stress were examined, and recommendations were offered for instructors of design courses.