ABSTRACT: We experimentally characterise the effect of layer temperature on the mechanical properties of PA6-CF manufactured by MEX. Ultimate tensile strength (UTS) and tensile modulus was investigated across layer temperatures ranging from 67 °C to 165 °C. UTS increased from 7.55 MPa at 67 °C to 36.04 MPa at 165°, while tensile modulus increased from 1.6 GPa at 67°C to 4.0 GPa at 140 °C. Measurements on a manufactured component show in-process layer temperatures between 88 °C and 123 °C. These findings quantify the attainable performance window and implications for functional component design.
ABSTRACT: This paper presents a novel research and development framework for “Design for R” (DfR), which aims to systematically translate R strategies into actionable targets in engineering design. Building on the principles of Design for X and guided by the Design Research Methodology, it outlines a comprehensive research structure for developing, testing, and iteratively refining the DfR approach. The goal is to facilitate specific and robust technical solutions as well as practically applicable sustainability integration at the product level through structured methods, tools, and design principles.
ABSTRACT: Barriers such as limited repair literacy and design-for-disposability continue to reinforce replacement cultures. This paper introduces AIFixer, an AI-powered interactive tool that guides consumers through electronic repair, promoting sustainable product lifecycles. Using a mixed-methods, user-centred approach, the study evaluates AIFixer’s usability and behavioural impact across real-world repair tasks. Findings show that conversational AI lowers barriers, builds confidence, and generates data for circular design, highlighting opportunities for multimodal and community-integrated development.
ABSTRACT: We introduce a method that turns online customer reviews into design insights. By analysing smartphone reviews, we extract the product features customers talk about and identify the sentiment linked to them. The approach combines Large Language Models (LLMs) with the Kano model, showing how specific features influence satisfaction or dissatisfaction. The results are coherent with the dimensions of the Kano model. The work demonstrates that LLMs can be informed and constrained by established design frameworks, bridging LMMs and design reasoning to provide theory-grounded insights.
ABSTRACT: Leveraging the vast interconnection of language and ideas through Large Language Models, a designer’s understanding of the needs, wants and desires of intended stakeholders defines the value proposition and product design requirements of a product or service through implementation of the Value Opportunity Analysis (VOA). The resulting VOA LLM Bot explores emotion, aesthetic and other human-valued attributes, and significantly increases perception of the VOA as a useful method for identifying product requirements, and analyzing opportunity solutions.
ABSTRACT: Long-COVID is a complex, multi-system condition with variable care across the UK. Using a systems and design engineering approach underpinned by Model-Based Systems Engineering (MBSE), this study examined Long-COVID clinic pathways through semi-structured interviews with 15 clinicians and patients. Thematic analysis identified five domains—attitudes, relationships, service integration, technology adoption, and safety netting. The final synthesised swimlane diagram revealed opportunities to improve coordination, operational efficiency, and patient safety within evolving care models.
ABSTRACT: Traditional design methods fall short for complex socio-technical systems where social and technical elements co-evolve and emergent behaviors resist decomposition. This paper proposes a seven-stage Design for Complexity Framework integrating systems science and design theory. Stages 3–6 form an iterative co-evolution space where modeling, architecture, and stakeholder co-design mutually shape problem and solution development. A healthcare example illustrates how the framework’s co-evolutionary approach addresses coordination failures that purely technical or purely participatory methods miss.
ABSTRACT: We examine how the social condition of work influences design cognition. By applying cognitive load theory, we explore that individual work fosters internal self-regulation and user-centered pragmatism, whereas group work creates the collaborative substitution paradox, in which digital resources supplant interaction, thus encouraging external regulation and experiential narratives. The findings suggest that social conditions act as a moderator of cognitive load, indicating that individual work is beneficial for deep learning, while structured group work help mitigate substitution effects.
ABSTRACT: Product development increasingly integrates generative AI tools to enhance creativity and efficiency. However, their actual impact on structured design work, particularly on method application and resulting designs, is not well understood. This study examines the effect of (1) method application quality on (2) product concept quality, influenced by (3) potential confounders like AI usage. Statistical analysis reveals that method application quality correlates positively with product concept quality, while higher AI usage correlates negatively with both, indicating limitations in AI usefulness.
ABSTRACT: Life cycle assessments identify environmental hotspots, yet translating these insights into design actions remains slow and expert-dependent. Existing AI tools lack a dynamic link to current research. Here, we present an LLM-driven pipeline that interprets LCA hotspots, mines recent literature, and extracts feasible, research-backed design alternatives. In a case study on a headlamp control unit, the method produced relevant and applicable improvements, indicating its value for accelerating sustainable product design.
ABSTRACT: This study synthesises interdisciplinary research on design strategies and attributes for extended product life of furniture. Through an integrative literature review, it develops the heuristic Longevity Trinity framework, comprising technical, functional, and emotional orientations. The framework consolidates dispersed design principles and highlight how the physical and psychological properties of furniture interact with the component of time, positioning product longevity as a design problem of continuity; continuity of materials, usefulness, and meaning across multiple lifecycles.
ABSTRACT: Solar photovoltaic systems are a key renewable energy solution, but behavioural rebound effects offset their environmental potential. As Solar Home System adoption expands in low- to middle-income countries, understanding how contextual factors (e.g., social norms) shape these effects is crucial, yet research on this topic is scarce. Through a systematic literature review, this study identifies 15 contextual factors influencing behavioural rebound mechanisms (BRM). Findings are integrated into a design tool, helping developers analyse contexts, anticipate BRM, and apply prevention strategies.
The transition to Industry 5.0 (I5.0) marks a shift toward human-centric, sustainable, and resilient manufacturing, leveraging technologies like collaborative robots (cobots) and AR/VR to enhance inclusivity, empowerment, and safety. This study investigates how Learning Factories (LFs) can effectively convey I5.0 principles to students and professionals. A simulated production line using AR/VR allowed participants to interact with virtual cobots, assessing key pillars of safety, inclusivity, and empowerment. A survey was used to assess the impact of this immersive environment on participants' perceptions and unconscious reactions. The findings demonstrate LFs' potential to prepare a workforce that integrates human creativity with technological innovation.
Digital transformation has reshaped the manufacturing sector, driving innovation and new business models. Simultaneously, sustainability pressures and stricter regulations push companies to adopt circular economy (CE) principles, focusing on reducing, reusing, and recycling materials. This transition requires adapting business models, product design, and management while integrating processes such as reverse logistics. Digital technologies play a crucial role by enabling data generation, processing, and analysis, optimizing production, and reducing resource use. However, many companies face knowledge gaps regarding how to implement these technologies effectively for CE. This study addresses these challenges through a systematic literature review, offering a framework that links digital technologies to CE principles, focusing on slowing, narrowing, and closing material loops.
The healthcare sector is a large contributor to climate change, due to their size, resource use and extensive use of single-use devices (SUDs). Despite the European Medical Device Regulation (MDR) permitting the resetting of SUDs, healthcare professionals are hesitant and seek evidence-based guidelines. This demonstration study investigates how design engineering can contribute to the feasibility of resetting SUDs that are theoretically suitable for reuse, contributing to the broader discussion on medical device sustainability. The research focuses on the quality evalualtion of reset SUDs through a detailed protocol ensuring that reused devices meet safety and performance standards. Results reveal a discrepancy between the theoretical feasibility of resetting SUD and its actual practicability. This finding highlights the necessity for more practically oriented protocols.
The main objective of this paper is the investigation of possibilities to enhance the resilience and sustainability of technical systems by means of function-oriented system design. Design for Resilience aims at creating technical systems capable of withstanding and adapting to internal and external changes. Design for Sustainability has the objective to create solutions that meet present needs without compromising future generations, for instance by means of avoiding environmental destruction, improving resource efficiency, and achieving a long-term ecological balance. Function-oriented design is the most abstract form of solution generation. This paper presents arguments to verify the hypothesis that function-oriented system design is a prerequisite for both Design for Resilience and Design for Sustainability, discusses connections between both aspects, and proposes a common process.
The properties of the external environment such as colour, light, sound and scent, have been shown to influence the emotional responses of the people in those spaces. However, these findings are typically drawn from studies using stimuli designed by researchers. It remains unclear whether workspace designers can intentionally elicit specific emotional responses in the occupants of those spaces. To address this, we evaluate two workspaces designed by students to ‘activate’ and ‘relax’ their occupants. The spaces were used as stimuli in a controlled experiment conducted during a design exhibition. Self-report measures of emotions showed that the activating room energised its occupants and the relaxing room both calmed and reduced the tension perceived by its occupants. Future analyses will determine whether physiological and behavioural measures are consistent with these findings
This study explores the impact of new work practices on product development in an Engineering Simulator by comparing traditional practices with new ways of working in a compressed product development process. By introducing flexibility, digital tools, and autonomy, the study highlights improvements in individual productivity and innovation. For example, teams employing new work practices developed their first prototypes 30% faster than control groups. However, challenges in communication and team dynamics emerge, underscoring the need for structured support systems. The findings further suggest that while these modern practices foster creativity and efficiency, successful implementation at the organizational level requires balancing autonomy with clear guidelines and effective management. This study provides actionable insights for adapting new work methods to engineering environments.
How well a team can design something depends on how well their collective understanding comes together. In the design of modern complex systems this involves multiple conceptualisations of the system undergoing design. These perspectives become instantiated in a large volume of design description that is deep, wide and diverse. This must carry shared meaning reliably, which is impossible to assure if the ontology in which every statement is nested is left implicit and unmanaged. This paper outlines a technical approach to assure ontological harmony without necessarily or only employing formal semantically rigorous knowledge representations. It empowers an incremental investment in description coverage and ontological coherence, better supporting the spectrum of thinking styles and description needs that design teams encounter when taking on complex systems development today.
This study proposes an ML-based interactive framework for early-stage design, addressing the challenge where physical prototypes are accurate but costly, and virtual prototypes are affordable but less reliable. The NN-based human-in-the-loop framework integrates pre-training and fine-tuning techniques to reduce reliance on extensive physical prototyping while maintaining model accuracy. Using projectile motion as an example, the framework demonstrates its ability to guide design by iteratively updating models based on limited experimental data and human expertise. The results highlight the framework’s effectiveness in achieving performance comparable to models trained on larger datasets, offering a cost-effective solution for creating accurate design models.
