J. Faludi
Please Note
17 records found
1
This project developed a strategic sustainability assessment framework that closes this gap. It embeds three established assessment methods into the existing development process at early stages, where design flexibility is still high, structuring sustainability information to inform design decisions rather than producing designs itself. Its value is twofold: it gives teams a structured basis for comparing design options before they are locked in, and it produces audited lifecycle data operators can use for their reporting obligations. Although developed with Infosys, it targets a structural problem common to telecom hardware value chains, suggesting relevance beyond this setting.
The framework was developed using Design Science Research, in which knowledge is generated by designing and evaluating an artifact that solves a real-world problem (Peffers et al., 2007), suiting a project aimed at building and testing a solution rather than only describing it. The work ran in two phases. The first mapped the problem context through a literature review, a value chain analysis, and an analysis of the internal development process, drawing primarily on semi-structured interviews with eight stakeholders across the chain, including operators, a supplier, and logistics and refurbishment partners. The findings were synthesised in a SWOT analysis of Infosys's position. The SWOT analysis surfaces a central tension. Infosys holds the position and the data to act: it sits at the centre of the value chain and can already access the lifecycle data scattered across actors (strength and opportunity). Yet the structure works against using them. The data is never consolidated before development begins, assessments arrive after design decisions are fixed, and no monetary value is attached to Scope 3 reductions, so the actor best placed to act has the weakest incentive to do so (weaknesses and threat).
The second phase developed and tested the framework on top of the existing process rather than replacing it. Three methods were introduced where they add the most value. Whole System Mapping brings a cross-functional team together to map the product system and identify high-leverage interventions before detailed data is required. Quick LCA scores the resulting ideas on environmental impact using incomplete or estimated data, showing which options have the most potential. A Total Cost of Ownership model then makes trade-offs between design options explicit in annual cost and annual CO2e, once supplier proposals are in. Each method feeds the next, together producing a prioritised set of interventions before the request for proposal, trade-off advice for vendor selection, and a third-party audited lifecycle assessment at the end of the cycle that supports operators' CSRD reporting. The methods were adapted from existing work in sustainable design and refined through workshops and validation sessions.
The framework was validated through separate sessions, each testing one method with a different group and a distinct goal. Participants valued Whole System Mapping for surfacing cross-functional perspectives that would not have emerged within a single team. They valued Quick LCA for quantifying the impact of ideas previously set aside without assessment, giving a basis for revisiting earlier decisions. And they valued the Total Cost of Ownership model for making long-term cost and CO2e trade-offs directly comparable for the first time, a dimension not previously considered systematically at Liberty Global. The complete framework was also presented to the ESG teams of Liberty Global and its operators, who valued it for structuring lifecycle data, presenting trade-offs, and improving reporting. Across the sessions, decision-makers recognised the logic of the methods immediately, but had never had a structured moment to apply them.
Together, the framework moves sustainability assessment from a post-production reporting activity to a structured part of development, at the points where design decisions are still open, and reinforces Infosys's position as an advisor rather than solely a development partner. The clearest sign it meets a real need is Infosys's decision to pilot it in the upcoming WiFi 8 modem cycle, for which a request for proposal is expected in the second half of the year. Its effectiveness under full conditions remains to be confirmed, as it has not yet run through a complete cycle and depends on data availability and cross-actor cooperation. Running the pilot and formalising data-sharing arrangements with Liberty Global are the immediate next steps. ...
This project developed a strategic sustainability assessment framework that closes this gap. It embeds three established assessment methods into the existing development process at early stages, where design flexibility is still high, structuring sustainability information to inform design decisions rather than producing designs itself. Its value is twofold: it gives teams a structured basis for comparing design options before they are locked in, and it produces audited lifecycle data operators can use for their reporting obligations. Although developed with Infosys, it targets a structural problem common to telecom hardware value chains, suggesting relevance beyond this setting.
The framework was developed using Design Science Research, in which knowledge is generated by designing and evaluating an artifact that solves a real-world problem (Peffers et al., 2007), suiting a project aimed at building and testing a solution rather than only describing it. The work ran in two phases. The first mapped the problem context through a literature review, a value chain analysis, and an analysis of the internal development process, drawing primarily on semi-structured interviews with eight stakeholders across the chain, including operators, a supplier, and logistics and refurbishment partners. The findings were synthesised in a SWOT analysis of Infosys's position. The SWOT analysis surfaces a central tension. Infosys holds the position and the data to act: it sits at the centre of the value chain and can already access the lifecycle data scattered across actors (strength and opportunity). Yet the structure works against using them. The data is never consolidated before development begins, assessments arrive after design decisions are fixed, and no monetary value is attached to Scope 3 reductions, so the actor best placed to act has the weakest incentive to do so (weaknesses and threat).
The second phase developed and tested the framework on top of the existing process rather than replacing it. Three methods were introduced where they add the most value. Whole System Mapping brings a cross-functional team together to map the product system and identify high-leverage interventions before detailed data is required. Quick LCA scores the resulting ideas on environmental impact using incomplete or estimated data, showing which options have the most potential. A Total Cost of Ownership model then makes trade-offs between design options explicit in annual cost and annual CO2e, once supplier proposals are in. Each method feeds the next, together producing a prioritised set of interventions before the request for proposal, trade-off advice for vendor selection, and a third-party audited lifecycle assessment at the end of the cycle that supports operators' CSRD reporting. The methods were adapted from existing work in sustainable design and refined through workshops and validation sessions.
The framework was validated through separate sessions, each testing one method with a different group and a distinct goal. Participants valued Whole System Mapping for surfacing cross-functional perspectives that would not have emerged within a single team. They valued Quick LCA for quantifying the impact of ideas previously set aside without assessment, giving a basis for revisiting earlier decisions. And they valued the Total Cost of Ownership model for making long-term cost and CO2e trade-offs directly comparable for the first time, a dimension not previously considered systematically at Liberty Global. The complete framework was also presented to the ESG teams of Liberty Global and its operators, who valued it for structuring lifecycle data, presenting trade-offs, and improving reporting. Across the sessions, decision-makers recognised the logic of the methods immediately, but had never had a structured moment to apply them.
Together, the framework moves sustainability assessment from a post-production reporting activity to a structured part of development, at the points where design decisions are still open, and reinforces Infosys's position as an advisor rather than solely a development partner. The clearest sign it meets a real need is Infosys's decision to pilot it in the upcoming WiFi 8 modem cycle, for which a request for proposal is expected in the second half of the year. Its effectiveness under full conditions remains to be confirmed, as it has not yet run through a complete cycle and depends on data availability and cross-actor cooperation. Running the pilot and formalising data-sharing arrangements with Liberty Global are the immediate next steps.
Healing Without Harm
Designing Medical Devices for a Circular Economy
A particular challenge within this context is posed by medical devices containing electronic components. These devices depend on critical raw materials and energy-intensive production processes and are composed of complex multi-material assemblies. At end of life, their disposal raises environmental concerns, as collection and recycling systems achieve only partial material recovery, while improper treatment of electronic waste can release hazardous substances into the environment. Together with rapid technological development and strict regulatory requirements, these factors complicate the application of circular approaches in design. This dissertation examines not only why this is the case, but also how it can be improved.
The central research question of this dissertation is therefore:
How can medical devices containing electronic components be redesigned to support a circular economy while ensuring clinical and regulatory compliance?
To answer this question, the dissertation is structured in five parts. Part I introduces the problem, exploring healthcare’s environmental impact, medical device design challenges, and the rationale for circular economy principles. Part II investigates the current state of medical device design through literature review and qualitative methods, identifying barriers and opportunities for circularity and clarifying how stakeholders can collaborate effectively. It also presents the Circular Healthcare Flows visual taxonomy, which shows how R-strategies can be implemented and maps how materials, components, and devices can circulate within clinical, regulatory, and operational contexts, providing a shared language and conceptual clarity for designers, clinicians, and policymakers. Part III presents two design case studies, demonstrating practical application of circular economy principles and highlighting trade-offs, integration challenges, and strategies to overcome them. Part IV translates these insights into practical approaches, forming the foundation for a Circular Design Guide. Finally, Part V discusses lessons learned, reflections, and directions for future research.
The research shows that circular strategies in healthcare are possible but context dependent. Analysis of over 1,400 medical devices revealed that while some devices incorporate reuse, most remain single use. Barriers are not only technological—they stem from regulations, institutional practices, and risk perceptions, while inconsistent terminology and concepts complicate coordination across stakeholders. The visual taxonomy helps address this conceptual ambiguity, enabling stakeholders to align on terminology, understand circular flows, and make context-sensitive decisions.
Design experiments illustrated how insights can be applied. Mid-level R-strategies such as reuse, repair, and refurbishment provide tangible environmental benefits without disrupting clinical workflows. Broader strategies, such as refuse, rethink, and reduce, offer greater impact but require reconsidering device use and care delivery. Trade-offs between circularity, safety, usability, and compliance can be navigated—and sometimes leveraged—through careful design, stakeholder engagement, and iterative testing.
These findings informed recommendations for a Circular Design Guide, offering practical steps to embed circularity into everyday medical device development. The research demonstrates that circular design in healthcare is achievable when environmental ambitions are balanced with clinical, regulatory, and operational realities.
Beyond individual devices, the work emphasizes broader implications. Collaboration across disciplines and organizations, digital tools to track and optimize device lifecycles, and education to embed circular thinking into practice are essential to scaling impact. Overall, this dissertation shows that sustainability and circularity in healthcare are not abstract ideals, but actionable approaches supported by tools such as the visual taxonomy and Circular Design Guide for medical devices, which can guide policy, industry practice, and future research. ...
A particular challenge within this context is posed by medical devices containing electronic components. These devices depend on critical raw materials and energy-intensive production processes and are composed of complex multi-material assemblies. At end of life, their disposal raises environmental concerns, as collection and recycling systems achieve only partial material recovery, while improper treatment of electronic waste can release hazardous substances into the environment. Together with rapid technological development and strict regulatory requirements, these factors complicate the application of circular approaches in design. This dissertation examines not only why this is the case, but also how it can be improved.
The central research question of this dissertation is therefore:
How can medical devices containing electronic components be redesigned to support a circular economy while ensuring clinical and regulatory compliance?
To answer this question, the dissertation is structured in five parts. Part I introduces the problem, exploring healthcare’s environmental impact, medical device design challenges, and the rationale for circular economy principles. Part II investigates the current state of medical device design through literature review and qualitative methods, identifying barriers and opportunities for circularity and clarifying how stakeholders can collaborate effectively. It also presents the Circular Healthcare Flows visual taxonomy, which shows how R-strategies can be implemented and maps how materials, components, and devices can circulate within clinical, regulatory, and operational contexts, providing a shared language and conceptual clarity for designers, clinicians, and policymakers. Part III presents two design case studies, demonstrating practical application of circular economy principles and highlighting trade-offs, integration challenges, and strategies to overcome them. Part IV translates these insights into practical approaches, forming the foundation for a Circular Design Guide. Finally, Part V discusses lessons learned, reflections, and directions for future research.
The research shows that circular strategies in healthcare are possible but context dependent. Analysis of over 1,400 medical devices revealed that while some devices incorporate reuse, most remain single use. Barriers are not only technological—they stem from regulations, institutional practices, and risk perceptions, while inconsistent terminology and concepts complicate coordination across stakeholders. The visual taxonomy helps address this conceptual ambiguity, enabling stakeholders to align on terminology, understand circular flows, and make context-sensitive decisions.
Design experiments illustrated how insights can be applied. Mid-level R-strategies such as reuse, repair, and refurbishment provide tangible environmental benefits without disrupting clinical workflows. Broader strategies, such as refuse, rethink, and reduce, offer greater impact but require reconsidering device use and care delivery. Trade-offs between circularity, safety, usability, and compliance can be navigated—and sometimes leveraged—through careful design, stakeholder engagement, and iterative testing.
These findings informed recommendations for a Circular Design Guide, offering practical steps to embed circularity into everyday medical device development. The research demonstrates that circular design in healthcare is achievable when environmental ambitions are balanced with clinical, regulatory, and operational realities.
Beyond individual devices, the work emphasizes broader implications. Collaboration across disciplines and organizations, digital tools to track and optimize device lifecycles, and education to embed circular thinking into practice are essential to scaling impact. Overall, this dissertation shows that sustainability and circularity in healthcare are not abstract ideals, but actionable approaches supported by tools such as the visual taxonomy and Circular Design Guide for medical devices, which can guide policy, industry practice, and future research.
Advancing Repairability in Consumer Electronics
Design Guidelines and Evaluation Methods
To fulfill this aim, this dissertation combines three complementary research activities. First, an in-depth observational study followed 24 participants, with and without prior repair experience, while they diagnosed faults in four common appliances and verbalized their reasoning. This qualitative data was supported by video analysis and post-task interviews. Second, more than ten thousand timed repair actions carried out by professional technicians on fifty-two appliances fed a quantitative model that links specific disassembly and reassembly operations to realistic proxy times, yielding the DaRT model (Disassembly and Reassembly Timing). Third, two successive studies compared six widely used repairability scoring systems against state-of-the-art design literature and then tested three of them empirically on sixteen products, comparing proxy-time and step-count approaches and probing best- and worst-case interpretations for each scoring systems.
Findings show that product architecture shapes user success in fault diagnosis more strongly than prior repair expertise. Clear visual or auditory feedback, component visibility, and unobstructed access prompt a direct or “pinpointed” search strategy, whereas hidden fasteners and recessed modules push users toward trial-and-error and early abandonment. Disassembly difficulty emerged as one of the main barriers that makes most people give up the diagnostic task. These insights were translated into a set of design guidelines that extend conventional principles of modularity and accessibility with new emphases on facilitating testing and providing component-level fault cues.
The DaRT model was able to predict real disassembly times for vacuum cleaners, washing machines and televisions with high accuracy while remaining easier to apply than complex methods such as eDiM. By explicitly including reassembly, DaRT provides a fuller picture of ease of a complete repair cycle. Validation against independent product assessment confirms accuracy.
Analysis of existing scoring systems revealed that most scoring systems weigh ease of disassembly appropriately but treat other decisive criteria such as spare-part price, diagnostic information and safety too sparsely or with ambiguous wording. In scenarios where repair is deemed infeasible or too expensive, the research demonstrated that the current scoring systems do not accurately represent the actual repairability of products. To address this issue, the study proposed the implementation of a limiting factor approach for criteria that determine the feasibility of repair. Proxy-time metrics like DaRT correlated more closely with measured effort than simple step counts, recommending a shift toward time-based assessment in future scoring systems with more weight on physical repairability of products.
This dissertation advances scientific understanding of repairability by emphasizing the critical yet underexplored role of fault diagnosis within product design and user interaction, presenting a holistic perspective that bridges technical elements with user cognition and behavior. It refines existing repairability assessment frameworks by highlighting gaps such as inadequate coverage of diagnostic aids and inconsistent weighting criteria, proposing improvements that enhance assessment validity and reliability. Moreover, this research introduces the DaRT proxy time model as a practical, accurate alternative to complex existing metrics, beneficial across diverse product categories. Societally and environmentally, this work supports the right to repair movement by empowering users to confidently diagnose and repair devices, thereby reducing electronic waste, informing purchasing decisions, and enabling manufacturers and policymakers to create genuinely repairable, sustainable products aligned with broader climate and circular economy goals.
...
To fulfill this aim, this dissertation combines three complementary research activities. First, an in-depth observational study followed 24 participants, with and without prior repair experience, while they diagnosed faults in four common appliances and verbalized their reasoning. This qualitative data was supported by video analysis and post-task interviews. Second, more than ten thousand timed repair actions carried out by professional technicians on fifty-two appliances fed a quantitative model that links specific disassembly and reassembly operations to realistic proxy times, yielding the DaRT model (Disassembly and Reassembly Timing). Third, two successive studies compared six widely used repairability scoring systems against state-of-the-art design literature and then tested three of them empirically on sixteen products, comparing proxy-time and step-count approaches and probing best- and worst-case interpretations for each scoring systems.
Findings show that product architecture shapes user success in fault diagnosis more strongly than prior repair expertise. Clear visual or auditory feedback, component visibility, and unobstructed access prompt a direct or “pinpointed” search strategy, whereas hidden fasteners and recessed modules push users toward trial-and-error and early abandonment. Disassembly difficulty emerged as one of the main barriers that makes most people give up the diagnostic task. These insights were translated into a set of design guidelines that extend conventional principles of modularity and accessibility with new emphases on facilitating testing and providing component-level fault cues.
The DaRT model was able to predict real disassembly times for vacuum cleaners, washing machines and televisions with high accuracy while remaining easier to apply than complex methods such as eDiM. By explicitly including reassembly, DaRT provides a fuller picture of ease of a complete repair cycle. Validation against independent product assessment confirms accuracy.
Analysis of existing scoring systems revealed that most scoring systems weigh ease of disassembly appropriately but treat other decisive criteria such as spare-part price, diagnostic information and safety too sparsely or with ambiguous wording. In scenarios where repair is deemed infeasible or too expensive, the research demonstrated that the current scoring systems do not accurately represent the actual repairability of products. To address this issue, the study proposed the implementation of a limiting factor approach for criteria that determine the feasibility of repair. Proxy-time metrics like DaRT correlated more closely with measured effort than simple step counts, recommending a shift toward time-based assessment in future scoring systems with more weight on physical repairability of products.
This dissertation advances scientific understanding of repairability by emphasizing the critical yet underexplored role of fault diagnosis within product design and user interaction, presenting a holistic perspective that bridges technical elements with user cognition and behavior. It refines existing repairability assessment frameworks by highlighting gaps such as inadequate coverage of diagnostic aids and inconsistent weighting criteria, proposing improvements that enhance assessment validity and reliability. Moreover, this research introduces the DaRT proxy time model as a practical, accurate alternative to complex existing metrics, beneficial across diverse product categories. Societally and environmentally, this work supports the right to repair movement by empowering users to confidently diagnose and repair devices, thereby reducing electronic waste, informing purchasing decisions, and enabling manufacturers and policymakers to create genuinely repairable, sustainable products aligned with broader climate and circular economy goals.
3D printing for repair
Design tools and methods for printed spare parts by manufacturers and consumers
In this dissertation, we explore how additive manufacturing can be used to produce plastic spare parts for the repair of consumer products. By reviewing the repairs of consumer products in repair café’s, we estimate that around 8-29% of plastic spare parts are currently suitable for additive manufacturing. As most parts are currently unsuitable for additive manufacturing, the design of these printed spare parts needs to be aligned with the capabilities of the technology. This requires a better understanding of the specific design considerations. We need to find what design aspects are suitable for the use of additive
manufacturing and which are more difficult. This will help us to determine the design complexity and what the biggest design challenges will be. Also, we investigate how to design parts that facilitate the use of additive manufacturing. Since parts can be designed by either the consumer or the manufacturer, it is important to distinguish between design in consumer self-repair and in manufacturer-enabled professional repair. These design perspectives are explicitly included in this dissertation.... ...
In this dissertation, we explore how additive manufacturing can be used to produce plastic spare parts for the repair of consumer products. By reviewing the repairs of consumer products in repair café’s, we estimate that around 8-29% of plastic spare parts are currently suitable for additive manufacturing. As most parts are currently unsuitable for additive manufacturing, the design of these printed spare parts needs to be aligned with the capabilities of the technology. This requires a better understanding of the specific design considerations. We need to find what design aspects are suitable for the use of additive
manufacturing and which are more difficult. This will help us to determine the design complexity and what the biggest design challenges will be. Also, we investigate how to design parts that facilitate the use of additive manufacturing. Since parts can be designed by either the consumer or the manufacturer, it is important to distinguish between design in consumer self-repair and in manufacturer-enabled professional repair. These design perspectives are explicitly included in this dissertation....
This research is structured in a three-phase iterative framework. The initial phase involves problem analysis and the development of design specifications. The next phase, material exploration, identifies a list of potential bio-based materials suitable for design exploration, followed by a literature review to understand their flammability and moisture resistance properties, which are critical for compliance with the rigorous standards of aircraft applications.
From the material exploration, a family of hardwood, natural fibers, and mycelium emerged as potential materials for further design exploration. Lightweighting method was employed to optimize their geometry and meet the required mechanical strength established in the design specifications (Load bearing strength up to 100kgs). This method led to the development of a more practical option: the Designing of Composites. Static load-bearing capacity calculations were conducted to assess the feasibility of the composite design with the variations in facesheet materials. The pretreated Baxis Sinica wood panel with a mycelium core emerged as a feasible solution, primarily due to its weight-to-strength ratio, ability to meet the functional requirements of aircraft, and its circularity.
In the pursuit of material optimization, studies were undertaken in exploring bio-based coatings, to enhance the flammability and moisture resistance properties ensuring its suitability for the stringent requirements of aircraft applications. With established research on enhancing the flammability and water resistance of wood-based composites, the focus was to improving the properties of mycelium. Initial post-treatment methods using inorganic flame retardants like sodium silicate effectively demonstrated flame-extinguishing properties; however, further research is required to further enhance the material's water resistance. Additionally, there is promising potential for utilizing bio-based coatings to simultaneously improve both the flame retardancy and moisture resistance of mycelium. As it is well-established that bio-derived materials can degrade over time, it is crucial to develop strategies and treatments to ensure this does not compromise the product's lifespan. Current efforts also focuses on understanding the long-term behavior of these materials and their coatings under extreme conditions. However, as these materials have not yet reached full maturity, further optimization and enhancement remain within the scope of future research.
Positioned within the framework of Circular R-strategies, this study proposes an ambitious design, utilizing a wood and mycelium to develop a composite, with textile serving as the adhesive layer. The proposed design not only eliminates the need for fossil-based materials but also reduces weight by up to 50% compared to conventional thermoplastics in seat trims. This weight reduction is significant, as even a single kilogram less can lead to a decrease of 5,000 to 15,000 kg CO2 emissions over the aircraft's lifetime. ...
This research is structured in a three-phase iterative framework. The initial phase involves problem analysis and the development of design specifications. The next phase, material exploration, identifies a list of potential bio-based materials suitable for design exploration, followed by a literature review to understand their flammability and moisture resistance properties, which are critical for compliance with the rigorous standards of aircraft applications.
From the material exploration, a family of hardwood, natural fibers, and mycelium emerged as potential materials for further design exploration. Lightweighting method was employed to optimize their geometry and meet the required mechanical strength established in the design specifications (Load bearing strength up to 100kgs). This method led to the development of a more practical option: the Designing of Composites. Static load-bearing capacity calculations were conducted to assess the feasibility of the composite design with the variations in facesheet materials. The pretreated Baxis Sinica wood panel with a mycelium core emerged as a feasible solution, primarily due to its weight-to-strength ratio, ability to meet the functional requirements of aircraft, and its circularity.
In the pursuit of material optimization, studies were undertaken in exploring bio-based coatings, to enhance the flammability and moisture resistance properties ensuring its suitability for the stringent requirements of aircraft applications. With established research on enhancing the flammability and water resistance of wood-based composites, the focus was to improving the properties of mycelium. Initial post-treatment methods using inorganic flame retardants like sodium silicate effectively demonstrated flame-extinguishing properties; however, further research is required to further enhance the material's water resistance. Additionally, there is promising potential for utilizing bio-based coatings to simultaneously improve both the flame retardancy and moisture resistance of mycelium. As it is well-established that bio-derived materials can degrade over time, it is crucial to develop strategies and treatments to ensure this does not compromise the product's lifespan. Current efforts also focuses on understanding the long-term behavior of these materials and their coatings under extreme conditions. However, as these materials have not yet reached full maturity, further optimization and enhancement remain within the scope of future research.
Positioned within the framework of Circular R-strategies, this study proposes an ambitious design, utilizing a wood and mycelium to develop a composite, with textile serving as the adhesive layer. The proposed design not only eliminates the need for fossil-based materials but also reduces weight by up to 50% compared to conventional thermoplastics in seat trims. This weight reduction is significant, as even a single kilogram less can lead to a decrease of 5,000 to 15,000 kg CO2 emissions over the aircraft's lifetime.
DIW samples, achieving a balance between the required ink volume and the output volume was crucialto ensure consistent printing. Iterative adjustments to the g-code parameters and air pressure weremade to fine-tune the printing process, resulting in the production of samples for mechanical testing. Three-point bending tests were conducted on both casted and printed samples to evaluate their mechanical properties. Stress-strain curves obtained from these tests were analysed to determine the flexural strength and overall mechanical performance of each ink formulation. Among the various recipes tested, Carob combined with alginate emerged as the strongest, demonstrating mechanical properties comparable to those reported in existing literature. Confirming its potential as a viable candidate for use in prototyping.
The findings of this research underscore the importance of optimising both material composition and production parameters in DIW processes. By successfully identifying and validating an ink formulation, this work contributes to the advancement of sustainable 3D printing technologies. ...
DIW samples, achieving a balance between the required ink volume and the output volume was crucialto ensure consistent printing. Iterative adjustments to the g-code parameters and air pressure weremade to fine-tune the printing process, resulting in the production of samples for mechanical testing. Three-point bending tests were conducted on both casted and printed samples to evaluate their mechanical properties. Stress-strain curves obtained from these tests were analysed to determine the flexural strength and overall mechanical performance of each ink formulation. Among the various recipes tested, Carob combined with alginate emerged as the strongest, demonstrating mechanical properties comparable to those reported in existing literature. Confirming its potential as a viable candidate for use in prototyping.
The findings of this research underscore the importance of optimising both material composition and production parameters in DIW processes. By successfully identifying and validating an ink formulation, this work contributes to the advancement of sustainable 3D printing technologies.
Improving the return rate of a smart pillbox in a circular economy
From product redesign to comprehensive guidelines
The investigation combined thorough analysis, engaging users and refining designs through iterations. The key findings emphasized the crucial factors of product hardware design and strategic communication in influencing users' abilities and willingness to return the smart pillboxes. Innovations in designing smart pillboxes, such as state switches, clear printed instructions, and digital reminders, have been introduced. Preliminary validations suggest that they are effective, but there is a need for further research to explore their combined impacts. Interestingly, this research highlights the importance of "Returners" as crucial stakeholders in the product return ecosystem. This underscores the need for tailored comprehension and design to meet their unique requirements.
Although the recommended guidelines have the potential to benefit a wider range of smart health devices, it is essential to validate them with more extensive participant groups. It is worth noting that the current research mostly focused on user ability, however, future studies are encouraged to explore the motivation dimension, which participants identify as a critical factor. This would help create a holistic approach to encourage voluntary product returns. ...
The investigation combined thorough analysis, engaging users and refining designs through iterations. The key findings emphasized the crucial factors of product hardware design and strategic communication in influencing users' abilities and willingness to return the smart pillboxes. Innovations in designing smart pillboxes, such as state switches, clear printed instructions, and digital reminders, have been introduced. Preliminary validations suggest that they are effective, but there is a need for further research to explore their combined impacts. Interestingly, this research highlights the importance of "Returners" as crucial stakeholders in the product return ecosystem. This underscores the need for tailored comprehension and design to meet their unique requirements.
Although the recommended guidelines have the potential to benefit a wider range of smart health devices, it is essential to validate them with more extensive participant groups. It is worth noting that the current research mostly focused on user ability, however, future studies are encouraged to explore the motivation dimension, which participants identify as a critical factor. This would help create a holistic approach to encourage voluntary product returns.
This thesis addresses the core issue of lower print quality in room-temperature printing of biomaterials. Its primary aim is to develop and optimize the print quality of these materials, fostering a deeper understanding of the key factors that influence their printing performance. Within the context of print quality, the study examines parameters such as dimensional accuracy, bridging, overhang performance, warpage, corner sharpness, surface finish, and precision. Furthermore, the research investigated the feasibility of reprinting these materials and its impact on their print quality. Extra attention was dedicated to investigating the influence of the rheology characteristics of the materials on the resulting print quality.
The research led to the creation of two materials, AB1 and CLAB4 and the optimization of print parameters to enhance their print quality. In doing so it elaborates on the influences of material composition, preparation and printing parameters on the print quality of biomaterials printed at room temperatures.
Of the materials developed, AB1 demonstrated exceptional bridging capabilities, achieving distances of up to 15 mm, minimal shrinkage (averaging 6% in the xy-directions and 4% in the z-direction), and good result precision. In contrast, CLAB4 excelled in surface finish, printing overhangs up to 40 degrees, and showcased higher efficiency in material preparation. Most noteworthy of both materials is their reprintability without evident degradation in print quality, a crucial feature for sustainable printing methodologies.
In this Research, rheology characteristics have proven to be pivotal due to their direct influence on material flow and behaviour. Unlike conventional melting-based printing, where materials flow upon heating and solidify once they are extruded, ambient printing requires inks to have specific rheology behaviours caused by changes in shear. Rheology governs how easily the ink flows when extruded and its ability to retain shape once extruded. Optimizing the shear-thinning behaviour and elastic recovery behaviour is crucial. This study elaborates on the specific aspect of rheology to improve enhancements in print quality, including Yield stress, flow stress, storage modulus, loss tangent and thixotropic response and recovery. Additionally, it presents interesting insights into how to optimise them based on material composition and preparation. Mixing the material before extrusion, for example, was shown to significantly increase the thixotropic response time, leading to more precise extrusion.
...
This thesis addresses the core issue of lower print quality in room-temperature printing of biomaterials. Its primary aim is to develop and optimize the print quality of these materials, fostering a deeper understanding of the key factors that influence their printing performance. Within the context of print quality, the study examines parameters such as dimensional accuracy, bridging, overhang performance, warpage, corner sharpness, surface finish, and precision. Furthermore, the research investigated the feasibility of reprinting these materials and its impact on their print quality. Extra attention was dedicated to investigating the influence of the rheology characteristics of the materials on the resulting print quality.
The research led to the creation of two materials, AB1 and CLAB4 and the optimization of print parameters to enhance their print quality. In doing so it elaborates on the influences of material composition, preparation and printing parameters on the print quality of biomaterials printed at room temperatures.
Of the materials developed, AB1 demonstrated exceptional bridging capabilities, achieving distances of up to 15 mm, minimal shrinkage (averaging 6% in the xy-directions and 4% in the z-direction), and good result precision. In contrast, CLAB4 excelled in surface finish, printing overhangs up to 40 degrees, and showcased higher efficiency in material preparation. Most noteworthy of both materials is their reprintability without evident degradation in print quality, a crucial feature for sustainable printing methodologies.
In this Research, rheology characteristics have proven to be pivotal due to their direct influence on material flow and behaviour. Unlike conventional melting-based printing, where materials flow upon heating and solidify once they are extruded, ambient printing requires inks to have specific rheology behaviours caused by changes in shear. Rheology governs how easily the ink flows when extruded and its ability to retain shape once extruded. Optimizing the shear-thinning behaviour and elastic recovery behaviour is crucial. This study elaborates on the specific aspect of rheology to improve enhancements in print quality, including Yield stress, flow stress, storage modulus, loss tangent and thixotropic response and recovery. Additionally, it presents interesting insights into how to optimise them based on material composition and preparation. Mixing the material before extrusion, for example, was shown to significantly increase the thixotropic response time, leading to more precise extrusion.
Redesign of Ultrasound Gel Bottle
A Systematic Sustainable Solution for the Radiology Department at the Leiden University Medical Center
Repair scorecards are used to evaluate products on those parameters. However, the current scorecards have abstract scores that are difficult to interpret. Therefore, this thesis proposes a quantitative tool that calculates the total cost of ownership (TCOO) and service life of a product by modelling product lifetimes using failure modes.
This thesis begins with performing a literature study of linear economy and planned obsolescence, current scorecards, and their limitations. Questionnaires and interviews were conducted to understand what consumers wanted from a repair scorecard. The results from these were used to design the label and website of the TCOO tool. A system was created to facilitate the TCOO Excel tool, label, and website.
The mathematical model to calculate the TCOO was built-in to an Excel tool, and sample data was used to iterate upon them. Sensitivity analysis was also conducted to test the Excel tool. User tests were conducted to test if the Excel tool was intuitive to use and the flow of the tool iterated upon. User tests were conducted to refine the design of the label and the website.
The main contribution of this thesis lies in presenting the factors of repairability, durability and product lifespan in terms of cost, modelling product lifetimes, and moving from a priority component-based calculation system to a failure mode-based system. Using this tool, consumers can make informed purchase decisions, and manufacturers get data regarding failure, and legislators get data to introduce new laws and mandates.
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Repair scorecards are used to evaluate products on those parameters. However, the current scorecards have abstract scores that are difficult to interpret. Therefore, this thesis proposes a quantitative tool that calculates the total cost of ownership (TCOO) and service life of a product by modelling product lifetimes using failure modes.
This thesis begins with performing a literature study of linear economy and planned obsolescence, current scorecards, and their limitations. Questionnaires and interviews were conducted to understand what consumers wanted from a repair scorecard. The results from these were used to design the label and website of the TCOO tool. A system was created to facilitate the TCOO Excel tool, label, and website.
The mathematical model to calculate the TCOO was built-in to an Excel tool, and sample data was used to iterate upon them. Sensitivity analysis was also conducted to test the Excel tool. User tests were conducted to test if the Excel tool was intuitive to use and the flow of the tool iterated upon. User tests were conducted to refine the design of the label and the website.
The main contribution of this thesis lies in presenting the factors of repairability, durability and product lifespan in terms of cost, modelling product lifetimes, and moving from a priority component-based calculation system to a failure mode-based system. Using this tool, consumers can make informed purchase decisions, and manufacturers get data regarding failure, and legislators get data to introduce new laws and mandates.
Because of the preceding, this thesis aimed to design and fabricate a cost-effective spectrally resolved albedometer that will measure the global and reflected irradiance in three different parts of the solar spectrum using photodiodes as sensing elements. This thesis demonstrates how the device's optical, electrical, and mechanical characteristics can be optimized to obtain a more accurate estimation of the spectral albedo.
Additionally, a bio-inspired casing design with self-shading properties was created to reduce the temperature inside the device. Two prototypes were fabricated with two different colour-diffuser configurations (Grey-N-BTK diffuser and White-Hybrid diffuser). Data measured by the final prototypes was calibrated and validated with measurements from an EKO MS700 spectroradiometer. The final sensors have an average error of 20.4% and 7.3% and operate at 17ºC and 8.6ºC above ambient temperature. The albedometers have a volume of 810 cm2 and cost around €978. ...
Because of the preceding, this thesis aimed to design and fabricate a cost-effective spectrally resolved albedometer that will measure the global and reflected irradiance in three different parts of the solar spectrum using photodiodes as sensing elements. This thesis demonstrates how the device's optical, electrical, and mechanical characteristics can be optimized to obtain a more accurate estimation of the spectral albedo.
Additionally, a bio-inspired casing design with self-shading properties was created to reduce the temperature inside the device. Two prototypes were fabricated with two different colour-diffuser configurations (Grey-N-BTK diffuser and White-Hybrid diffuser). Data measured by the final prototypes was calibrated and validated with measurements from an EKO MS700 spectroradiometer. The final sensors have an average error of 20.4% and 7.3% and operate at 17ºC and 8.6ºC above ambient temperature. The albedometers have a volume of 810 cm2 and cost around €978.
will last for ever. Starting off with two audio inputs and one output, it can also expand, with the installation of additional audio mod- ules, in order to accommodate more audio sources. Moreover, with extension plug-ins, it can support music protocols other than a raw audio signal, in order to keep up with new technologies. Those form fitted blocks can introduce Bluetooth, AirPlay, Optical, or even Phono Pre-amplification functional- ities and so on. Wi-Fi connectivity enables remote control of the console’s motorised volume knobs, through a mobile application. IR receivers and transmitters, hidden out of sight, can identify pattern signals of tradi- tional remote controls and replicate them, gaining this way control of other devices in the room. Each audio channel is also equipped with a customisable button and its function can be programmed to the users liking.
Sustainable design, with minimised environ- mental impact and great repairability. IMO is using a short bill of materials, most of which are either already recycled or great for recycling at end of life. Reversible fasteners are dominating the structure, without the use of any destructive adhesives. The sim- ple assembly of the housing and the elec- tronics, make repairs easy and essentially fool-proof. A single HEX key (Allen key), is needed to fully dismantle the entire product. Common, off-the-shelf electronics, that are easy to understand and identify, are used for the internal circuits. Internal circuitry communications are handled by connectors widely available to the public, making re- pairs even more manageable. ...
will last for ever. Starting off with two audio inputs and one output, it can also expand, with the installation of additional audio mod- ules, in order to accommodate more audio sources. Moreover, with extension plug-ins, it can support music protocols other than a raw audio signal, in order to keep up with new technologies. Those form fitted blocks can introduce Bluetooth, AirPlay, Optical, or even Phono Pre-amplification functional- ities and so on. Wi-Fi connectivity enables remote control of the console’s motorised volume knobs, through a mobile application. IR receivers and transmitters, hidden out of sight, can identify pattern signals of tradi- tional remote controls and replicate them, gaining this way control of other devices in the room. Each audio channel is also equipped with a customisable button and its function can be programmed to the users liking.
Sustainable design, with minimised environ- mental impact and great repairability. IMO is using a short bill of materials, most of which are either already recycled or great for recycling at end of life. Reversible fasteners are dominating the structure, without the use of any destructive adhesives. The sim- ple assembly of the housing and the elec- tronics, make repairs easy and essentially fool-proof. A single HEX key (Allen key), is needed to fully dismantle the entire product. Common, off-the-shelf electronics, that are easy to understand and identify, are used for the internal circuits. Internal circuitry communications are handled by connectors widely available to the public, making re- pairs even more manageable.
Sustainable opportunities in the Fashion industry
Easing the transition to a slower, user-inclusive production model for Maium
Maium is an Amsterdam-based fashion company that produces recycled PET raincoats and that highly values sustainability in its practices, wanting to lead as an example for other fashion brands.
Market and brand analysis (through tools such as 4C analysis and SWOT analysis) are the starting point of this research, which aimed at analysing Maium’s environmental impact through Life Cycle Assessments and finding more sustainable alternatives to their current production model. The design process consisted in applying tools like VentureWell’s Whole System Mapping and Presidio Sustainability Booster to the results of the LCAs. The process has been an iterative one, so as to best define pain points and opportunities, and thoroughly think of the possible solutions that could be implemented.
The design solution has the intent of including the final users in the clothes’ lifetime extension process by teaching them techniques and skills that they can apply to their raincoats and to other pieces of clothing as well. Moreover, the intent has been also to provide them with as much information and transparency as possible for what concerns the production processes, the supply chain and alternative business models to the linear one. ...
Maium is an Amsterdam-based fashion company that produces recycled PET raincoats and that highly values sustainability in its practices, wanting to lead as an example for other fashion brands.
Market and brand analysis (through tools such as 4C analysis and SWOT analysis) are the starting point of this research, which aimed at analysing Maium’s environmental impact through Life Cycle Assessments and finding more sustainable alternatives to their current production model. The design process consisted in applying tools like VentureWell’s Whole System Mapping and Presidio Sustainability Booster to the results of the LCAs. The process has been an iterative one, so as to best define pain points and opportunities, and thoroughly think of the possible solutions that could be implemented.
The design solution has the intent of including the final users in the clothes’ lifetime extension process by teaching them techniques and skills that they can apply to their raincoats and to other pieces of clothing as well. Moreover, the intent has been also to provide them with as much information and transparency as possible for what concerns the production processes, the supply chain and alternative business models to the linear one.
The Pavilion Roof
Modular Roof-System for Sustainable Household Provision