Inflators play a crucial role in interventional radiology and cardiology to restore blood flow to obstructed veins. Given the high-risk nature of these procedures, inflators must be sterile. Consequently, they are designed for only single-use. This practice results in the annual incineration of around 100.000 inflators annually in the Netherlands, contributing to approximately 62500 kg of CO₂-eq emissions.
Our research, employing literature review, HotSpot and Disassembly maps, interviews and observations identified key barriers to reuse of the current inflators. These devices are designed for single-use, applying materials that cannot withstand decontamination and lacking the ability to be disassembled. In addition, parts are fixed together to reduce the chances of failure during the procedure.
This master’s thesis proposes a circular model for endovascular inflators, focusing on the reuse of valuable components within healthcare institutions while disposing of the rest. POMPA. POMPA is a circular redesign of the inflators. It aims to make inflators easy and safe to use, disassemble, decontaminate, reassemble and reuse. POMPA adopts materials suitable for decontamination and redesigns the architecture of inflators to achieve complete dis- or reassembly of the product in less than a minute without compromising its functions and performance.
The new system and product-level interventions enable the decontamination and reuse of key components for about 1000 patient procedures. POMPA has a lower environmental and economic impact than current single-use inflators after just nine uses.
In conclusion, POMPA offers a sustainable, convenient, and safe alternative to single-use inflators. This conceptual solution has many features that can be further explored and improved, but for now, it is intended to be a first step towards more circular inflators and to inspire similar innovation change in other medical devices.

This graduation project, conducted in collaboration with Sony Corporation, explores how over-ear wireless headphones can be redesigned to better align with the principles of the circular economy. The current design of consumer electronics, including headphones, largely follows a linear model. This results in short product lifespans, limited repair options and significant challenges for recycling. This project takes a different approach, fundamentally rethinking how users interact with and care for their products.

While most consumer electronics are designed as closed systems, this project investigates how design can shift the perception of headphones from being a ‘black box’ to an understandable and approachable object.

The analysis of five existing headphone models identified key barriers to circular user behaviour, including complex design, inaccessible critical components, difficult disassembly processes due to interdependencies, the extensive use of adhesives, lack of intuitiveness and the product being perceived as a ‘black box’.

In response, a new concept was developed that centres on re-teaching the practice of product care through clarity. Central to the design is an illustrated book featuring transparent elements that serves as a walk-through of the headphones. This allows users to familiarise themselves with the headphones’ internal architecture, functions and maintenance possibilities without risking damage.

According to the principles of this book, the Sony WH-1000XM5 has been redesigned to follow the same modular, layered structure. Transparent structural parts and colour coding by function reinforce the visual connection between the two. The book and the headphones work together as a single system, with each one strengthening the other.

The final concept demonstrates how design can encourage users to take care of their products by teaching them how to maintain, repair and handle them responsibly throughout their lifecycle.

This project introduces a new approach to circular design and product design in general, placing the supply of information at the centre and adapting and optimising the design of the product to support it.

This report aimed to take a look at the relation between repair and recycling, while considering the user aspects and application. This has been done by analysing two waterproof linear shaped luminaires on their ease of installation, repairability, and recyclability by doing interviews with installers and recyclers, using the Disassembly and Recyclabity map, and conducting a shredding experiment.

Insights from analyses which were interesting in the scope of this project included: repair of the luminaire on site is hardly done due to high labour costs and low failure rates of the components and installers are willing to disassemble at the end of life to improve liberation in recycling. Shredding experiments showed complications in the recyclability of the seal, metal folding around other parts and materials not being recycled in the WEEE line, like PC.

As a result of the analyses, redesign directions have been identified and ideas have been generated. From those ideas, one concept has been chosen with the help of experts to maximise the benefits in the installation, repairability and recyclability, as well as the feasibility and costs.

In the redesign focus lay on making the parts in need of maintenance (the battery and driver) and the electrical connector quickly and easily accessible for the installer on site, while improving the recyclability of the luminaire and considering the application requirements of waterproofness. The redesign shows both the driver and batteries are accessible on site in 10 seconds with a complete battery replacement taking 31 seconds in total (compared to 148 in the old design). Next to that, uni-material assemblies have been strived for to increase the recyclability.

The thesis finalises with an advice to designers on how to design for recycling, repair, and for all domains simultaneously and shows the relevance of keeping in touch with the intended user throughout the project.

Neurodegenerative diseases like Parkinson’s and Alzheimer’s have a huge impact on patients, their close ones and society as a whole. The negative consequences of these diseases are ever increasing due to our ageing society and growing shortage of healthcare personnel. Worldwide research efforts have thus far been unable to find effective treatment options.

Brain deterioration in neurodegenerative diseases sets in 15 to 20 years before clinical symptoms become noticeable. This means that even if better treatment options become available, much irreversible damage has been inflicted before we know to administer the treatment.

Early deterioration of smelling ability has been shown to provide a good risk indicator for future disease development. This thesis dives into the sense of smell as a means of recognizing neurodegenerative diseases preclinically.

An olfactory evaluation tool, called Knowse, was developed. This concept product was designed to make the well-known ODOFIN Sniffin’ Sticks test suitable for the context of case-finding for neurodegenerative diseases. Knowse transforms the Sniffin’ Sticks into an automatic self-test that people may use at a brain health clinic or optician. The product provides people with a relative trendline of their smelling ability, from which conclusions can be drawn over time.

This thesis report features a deep-dive into the neurodegenerative diseases Alzheimer’s and Parkinson’s, their impact and their current procedures. Possible future test locations, ethics of diagnostics and the current olfactory test market are explored through interviews and literature research.

Several design methods, prototypes and design iterations are described as they lead towards the final concept product of this thesis, Knowse. Design focused much on the technical, usability and error-proofing aspects of the concept product.

Plastic pollution in Dutch waterways is a growing environmental challenge, contributing to ecological damage, public health risks, and increased operational costs for maintenance and cleanup. This report focuses on the redesign of Noria’s floating litter tracker, the TrashTracer, to address key limitations in the original design, including water ingress, insufficient durability, and high production costs. By employing a user-centered design process, the project incorporated modularity, improved waterproofing, better signal reliability, easier recovery, lower chances of losing the tracker and extended battery life, resulting in a more effective research tool.
Through iterative prototyping, stakeholder feedback, and technical analysis, the redesigned tracker enhances operational efficiency and creates added value. The project also ensures the tracker aligns with Noria’s mission to research and mitigate plastic pollution, contributing to broader efforts to improve the quality of aquatic ecosystems in the Netherlands. The report concludes with an evaluation of the project’s results and recommendations for implementation.

This project aims to develop an easy-to-use method to (re)design products for ease of disassembly and subsequently for circular strategies, such as repair, refurbish, remanufacture, etc. Improving repairability is one of the first steps in decreasing the environmental impact of products by prolonging their technical lifespan. This thesis focuses on two separate tools that have the potential to be integrated: the Hotspot Mapping tool and the Disassembly Map. Both tools assess a product by disassembling it into its core parts and recording the properties of the parts and the disassembly steps (Fazio & et al., 2021; Flipsen et al., 2020).
The Hotspot Mapping tool highlights parts and disassembly activities that are important due to their failure rate, functionality, disassembly effort, and environmental and economic impact. On the other hand, the Disassembly Map uses these highlighted features to create a visual representation of the product architecture. Since the inputs for both tools are similar, it raises the question of whether it is possible to link them together.
The tools are analysed by literature review and usability questionnaires, resulting in a usability score of the original tool and strengths and weaknesses in terms of features and usability. Through an iterative approach, a new tool is developed, that uses a node/edge lists data structure to describe the product architecture of a product. This data-structure allows for the automatic generation of a dynamic Disassembly Map (Figure 1) in the visualisation software program yEd Graph Editor. The dynamic Disassembly Map allows designers to select which properties to display and which to hide, enabling focused attention and a better overview.
Through user testing the new method has been proven to offer increased usability, requiring less time to fill in, and an overall preference by all usability test participants over the original Hotspot Mapping and Disassembly Map tools.

Action is working on sustainability in social compliance, materials, packaging and circularity but they still have a long way to go in becoming circular. The European Union is taking steps towards a circular economy with the New Circular Economy Action plan, The Green Deal and the Right to Repair. Countries and companies are taking measures where legislation on the European level is taking too long. Action’s geographic expansion is ending and needs to look for new opportunities. This thesis will focus on helping Action to take their responsibility in the cycle of products to make them more circular. This will help Action to stay resilient with upcoming European legislation, by being in compliance with present and foreseeable circularity legislation .This has led to the following research question: How to help Action in becoming Circular to stay resilient with present and foreseeable legislation?

Using the double diamond method the most vulnerable product group and corresponding circularity strategy was selected. The first diamond was used to select a product group to focus on and what strategy should be applied. The focus should be on repairability as it is a starting point for other CE strategies. Electrical and electronic equipment is the most vulnerable product group to legislation and is forcing Action to take responsibility after Energy Related Products (ErP) have been sold. ErP have the biggest potential to reduce CO2 emissions. Therefore, Action should focus on selling repairable ErP as a step towards circularity. The buyer has a lot of power in making decisions but is lacking the knowledge of making decisions in terms of circularity. The problem that needs to be solved is that the buyer is making decisions on purchasing ErP products while lacking repairability knowledge. This is developed in the last diamond of the double diamond method.

To help Action stay resilient with present and foreseeable legislation a repairability index is made which Action can use to quantify the repairability of products. This repairability index is specific for every ErP group and is made by Action. This is made possible through an index guide that helps select priority parts and reference values for the repairability index of every specific ErP group. Suppliers can fill in the repairability index using the supplier guide. A repairability index feedback system is used by the buyers to keep track of the repairability of the products they buy. The repairability index is accompanied by a future vision which aims that Action has build a vibrant ecosystem through innovative partnerships and collaborations in 2035, where Action works together with its manufacturers, repairers and customers to create a circular future where customers are empowered to repair Action's durable products more easily. Getting here is explained through a roadmap with three horizons.

This graduation project delves into the use of Additive Manufacturing (AM) to produce spare parts through a case study of vacuum cleaners. Waste from Electrical and Electronic Equipment (WEEE), including products like vacuum cleaners, challenges the European Union’s (EU) sustainability goals. In 2020 alone, the EU collected an estimated 12.4 million tonnes, representing 10.5 kilograms per person. To address this issue, the “Right to Repair” was adopted. This initiative aims to promote repair as a strategy to slow down WEEE by mandating companies offer 10 years of post-warranty spare parts availability and 15 days of lead time. This mandate challenges companies’ responsiveness due to the extended period of support and limited lead time. Am provides an opportunity to fulfil these requirements while also offering additional benefits such as the digitalisation of the supply chain and reducing the environmental impact of the company’s operations.
The main research goal of the project is the development of a framework for evaluating the suitability of components within a product to be AM printed as spare parts. The framework is established through a literature review across three primary research areas: Priority components (identifying key components for repair activities), Printability (assessing component suitability for AM printing) and Spare Part Suitability (evaluating components’ suitability for supply chain considerations). The proposed framework, encompassing three primary steps, narrows down the components from a complex product to focus on those that present greater AM eligibility. This, in turn, guides the company’s effort in designing, testing and making these eligible parts commercially available.
Step 1. Cut-off criterion: Aims to exclude components defined as not suitable for AM printing, such as standardized elements and electronics.
Step 2. Eligibility Evaluation: Assess components eligibility for AM spare parts printing within the research areas.
Step 3. Component Selection: A top-down approach is employed. It begins with the selection of repair priority components, from his group those deemed AM printable are identified, and finally, components aligned with supply chain suitability are selected.
Takeaways from the conducted research also involve the insights gathered from the conducted framework validation, which involved two Philips vacuum cleaners and the use of Selective Laser Sintering (SLS) for the printing of spare parts. Lastly, this thesis establishes a foundation for the exploration of AM potential in the realm of spare parts manufacturing and future product design.

Electric toothbrushes are the most effective method for maintaining oral hygiene, but also the method with the greatest environmental impact. Most of the impact of electric toothbrushes comes from transport, materials and parts. This means that by extending the product life and enabling local loops, the environmental impact of electric toothbrushes can be reduced. The circular economy encompasses multiple strategies that can be leveraged to achieve this.

So far, there has been little research into designing small waterproof personal care appliances for the circular economy. In this thesis, the challenges and opportunities for transitioning electric toothbrushes to the circular economy are uncovered and a design solution to these challenges and opportunities is proposed. The primary research question for this thesis is:

How can an electric toothbrush be designed suitable for the circular economy?

The first two phases of this thesis were dedicated to uncovering the challenges and opportunities for transitioning electric toothbrushes to the circular economy. In the first phase, research into the state of the circular economy of current electric toothbrushes was performed in which the academic, manufacturer and user perspectives were researched. This led to three key insights for the circular design of an electric toothbrush. In the second phase, an analysis was performed of the implementation of circular design strategies in a representative set of current electric toothbrushes. This led to four key insights for the circular design of an electric toothbrush.

In the third phase of the thesis, the key insights were translated to design challenges and a design solution to tackle these design challenges was conceived. This resulted in the Everbrush electric toothbrush concept.

The battery has been made user replaceable to tackle the primary reason for reaching the end of life, reduced battery performance. An aluminium main body was introduced that aims to increase product attachment by ageing with dignity, which should also increase repair considerations. Another aim of the aluminium main body is to reduce hygiene concerns when purchasing refurbished. The ease of disassembly has been improved significantly which can open up additional opportunities for product life extensions. The amount of elastomers has been reduced by introducing a rotating magnetic power switch, eliminating the need for a power switch seal and increasing high-value recycling performance. Lastly, permanent connections were avoided throughout the design, also increasing high-value recycling performance.

In this graduation project the design process: the Potential to Value Circle, for designing from a waste stream is presented. The Potential to Value Circle creates a structured way of working in which the potential of a waste stream is translated to value. Value is generated by combining the perspectives of material, stakeholders and context around a waste stream into a concept direction. Through this process, The Bin guides their clients to take the next steps in becoming part of a circular economy.

This project was done in collaboration with The Bin. The Bin is a startup in the circular economy. They help their clients to become part of a circular economy by creating circular concepts out of their waste streams and setting up a circular system around these concepts. These waste streams can be defined as products at their end-of-life or by-products from a production line.

Currently, the Bin bases its process on the circular frameworks the Value Hill (Achterberg et al., 2016), R9-list (Potting et al., 2017) and the Butterfly diagram (EllenMacArthur Foundation, 2019). These frameworks give the bin a high-level overview of circular value creation. However, they want to have a more step by step process that helps to turn waste streams into circular concepts. This was the essence of their request for this graduation project and resulted in the Potential to Value Circle.

The Potential to Value Circle approaches a waste stream from different perspectives, resulting in opportunities that get turned into a concept direction that uses the waste stream to move towards a circular economy. The Potential to Value Circle is built up in three phases, 1) Analysis, 2) Combining, and 3) Circular design goal. The first phase presents how an understanding of the elements around a waste stream can be created, by analysing material, stakeholders and context. Based on this, potentials are formulated. In phases 2 and 3, the potentials of phase 1 are combined, which allows translating the potentials of the waste stream into opportunities. With these opportunities, a concept direction is formulated that creates value. Three ways of applying the Potential to Value Circle are presented, on which the Workshop is elaborated further. The workshop shows how to work in three hours with the Potential to Value Circle to a circular design goal with the client.

With the already happening governmental regulations(The Netherlands), an increase in consumer price of natural gas is noticeable. With COVID-19 and now the war in Ukraine energy resources are becoming increasingly expensive. 90 percent Dutch houses are heated with gas. Based on the energy consultant, gas supplies an average to 9769 kWh of energy per m3. Each house use up to 1500 m3 per year. 14654 kWh for a year on an average is needed for one household. A heat pump (HP) needs about 6513 kWh average per year depending on type house, size and season. From society we are going through a shift from gas to electricity. For a house this can be done with replacing a gas based boiler with for instance a heat pump. But it doesn’t necessarily provide people the same scale of thermal comfort. Shouldn’t we rethink the way we feel comfortable in our homes? Design opportunities that contributes to Bosch’s future vision and mission are explored. The problem at the heart of this project is defined as: To what extent can a product increase the personal thermal comfort of the user and be more energy efficient? And can therefore a personal product provide the necessary heat if the central heating temperature settings is set to 18°C? User-centered design and thermal comfort are the key methodology and research supporting this project. Both were used for exploring the relationship between users’ behaviour (personal heaters) and the influencing factors, thereby providing valuable insights for all design directions. This project is finalized with a product concept, “Ori”, a flexible Far Infrared (FIR) heater that has multi product configurations and use-cases. It applies various design criteria based on the inputs of thermal comfort research, user interviews, heating technology research, aiming and product flexibility configurations to create a personal experience for users. If the challenges are addressed, Ori could be a valuable product for Bosch’s consumer products portfolio and offer the user financial benefit and a decrease in yearly electrical energy consumption. Ori will use up to 229 kWh per year which is nearly 10 times less compared to a conventional personal heater (2148 kWh). The performance would be measurable through a simulation of a working HP, a room, a user, Ori and a Predicted Mean Vote (PMV) measurement device that address thermal comfort (ISO 7730). In addition to this concept, this project has addressed possible opportunities and requirements in the field of FIR heating, which could be used as an input for other relevant product developments within Bosch’s (thermal) comfort and well-being department.

To improve efficiency, dairy farmers monitor the inputs and outputs of their cows based on data collected by sensors. Currently the main sources for this data are the given food and information about the milk (composition and volume). This data helps the farmer make better decisions regarding animal welfare and feeding practices. However, one of the outputs of the cow is currently not monitored, namely the manure.

A system that monitors herd manure data in a barn using sensor technology was proposed. It should give the farmer interpreted feedback enabling him to have more control over farm efficiency both financially and ecologically.

This Thesis report covers the creation and validation of a spreadsheet-based self-declared quantitative cost of ownership tool. The accompanying labelling Scheme informs customers about the Total Cost of Ownership (TCO) of their products with a focus on the Repair Costs. The Total Cost of Ownership Tool (TCOT) offers customers a better comparative potential with regard to the longevity of products.

The tool distinguishes itself from currently existing initiatives and tools for it provides a quantitative scoring of the cost of ownership and repair. This quantitative scoring is detrimental to the fair comparison of products. Previously existing tools mainly provided a qualitative grading. For this concept to work product manufacturers will be obliged by legislative organs to fill in the TCOT to get a corresponding label that needs to be displayed at the place of purchase. The tool in return provides the manufacturers with valuable data on how to improve their products. The newly obtained quantitative data can be used by legislators to assess the progress of longevity of products to assess the effectiveness of the newly adopted TCOT legislations.

To explore this solution space the cost of ownership and repair needed to be expressed in a mathematical formula. Thereafter the factors that influence the variables in this formula needed to be quantitatively expressed. One major qualitative element however remained. The grading of the chance of a successful repair was performed by including conditions and criteria of the French Repairability Index (FRI).
The development of the tool relied on iterative cycles of performing case studies with data on smartphones. The early iteration cycles revealed that small variations in the input variables resulted in significant differences in the outputs. Not only was the available literature on some of these variables limited. Often sources provided contradicting figures making conclusive results difficult to obtain. To test the technical aspects of the tool and assess the individual impacts of the input variables, different scenarios were explored. This provided insights into how the tool deals with the varying input data. The outcome of these tests fell within the bounds of expectation and revealed what further steps need to be undertaken to further develop the TCOT.

The quantitative display of these often unknown and intangible ownership costs provides the customer with the information that she needs to better be able to choose a longer-lasting product. This newly acquired transparency towards the customer can help legislators nudge manufacturers into producing longer-lasting products. The further development of the tool and its accompanying label scheme will help with the transition towards the envisioned circular European Union by 2050

At this moment, the problem of plastic pollution does not need an introduction. Although recycling rates are slowly rising, plastic pollution remains one of the biggest threads to the global ecosystem. Especially in low-to-middle-income countries, industrial recycling systems are sparse due to their required investment.

Precious Plastic is an organization aiming to tackle plastic pollution, step by step. They openly distribute blueprints of recycling machines for anyone to use, which enables local recyclers to start their own informal recycling workshop. Over 40,000 people in 400 workspaces are connected through the Precious Plastic Universe, in which recyclers, designers and plastic collectors collaborate. One of their machines is an injection machine, capable of injecting recycling plastic into a mold (figure 1). This machine is low cost, easy to build, and creates a beautiful marbled aesthetic that convincingly tells the story of the value of recycled plastic.

However, the design of the machine has quite a number of problems. Mainly, it requires an excessive amount of hand-force which exceeds human ergonomic limits. The machine also has a number of safety and buildability issues. Lastly, the machine does not easily enable tailoring due to its monolithic design. Next to the problems relating to the injection machine, Precious Plastic has noticed they often miss out on gathering improvements that builders implement in their machine. Due to this, valuable opportunities for development of the machine are not redeemed. This project aims to tackle these problems through two design outcomes. The first outcome is an online framework where users can tailor their injection machine based on their needs and upload their machine improvements. The concept aims to transform the current monolithic design sharing system into an inviting modular framework.

The second outcome is an advanced version of the injection machine. The goal aimed to develop, validate and document a functioning prototype of an advanced arbor injection machine. The design of the machine decreases the required input force by 70%, while producing a higher injection pressure and solving the prior safety and usage problems. The design of the machine was developed in active collaboration with a group of experienced machine builders and will be distributed throughout the Precious Plastic Universe.

In the end, both design outcomes contribute towards a more sustainable world, in which people are empowered through Open Source Hardware and plastic is in fact precious.

In this design research the goal is to design a Sustainable HiFi Solution that the user can and are willing to use during their Audio Life. Context Listening to music in the domestic domain is something everyone does, but not all in the same way. In this research user of HiFi systems are the focus. HiFi Enthusiast listen to music to experience their Music. For decades HiFi systems were quite sustainable, put together out of separate components, if one failed only that one needs replacement. However things have changed, digital and analog systems are combined in one enclosure. Problem All-in-One HiFi solutions gain in popularity amongst Music Enthusiasts. All-in-One solutions are small, everything is contained in one enclosure. Easy to use, a mobile phone and application can be used to control the system. Analog and digital systems are put together to increase the use cases, however the technical lifetime of the different components is different. The digital parts can last for 5 to 10 years, the amplification part 10 to 20 years. A sustainable alternative needs to be designed, with the same benefits for the Music Enthusiast. Approach During this design research the double diamond approach is utilized. First to discover the current situation and fill in knowledge gaps using expert interviews and Hotspot Mapping. Thereafter online questionnaires and in-depth interviews provided the remaining data to start the design process. The design process is split in two, first the gathered data is used to design an overall ‘enclosure’, which is tested with the Music Enthusiast. Thereafter the technical implications of the design are researched, prototyped and implemented. Findings For the Sustainable HiFi solution to be saleable in traditional HiFi stores it has to be usable in a demo room. The HiFi solution should be adaptable to the changing needs and wishes of the Music Enthusiast during their Audio Life. By focusing on adaptability the sustainability aim can best be achieved via a new product design. For the Sustainable HiFi Solution to utilize its sustainable potential to the fullest different parts of the system should be designed using different circular design methods. In the new design unused functions should not be present in the system. Results The Critical Design Challenges for a Sustainable HiFi solution have been met. A modular design was made that can adapt to the Music Enthusiast wishes and needs with regards to Aesthetics, Functionality and Ease of Use. The different modules are easy to replace, without any tools, with the push of a button. The current status of the design is enough to clearly communicate the ideas and reasoning behind the concept. The next step would be to make a minimal viable product to demonstrate the potential of the IMS system to the Music Enthusiast.

Trust is a major contributor to a team's performance. Trust needs time to be built. Engaging into an open discussion can shorten the time needed to build trust. The well-being tracking tool support students and coaches in their way of communicating their emotions about the project. This leads to: 1. A lower chance of conflicts within the team 2. A higher chance of understanding each other 3. A better teamwork experience 4. By talking about emotions, you are being open and vulnerable, which can only happen in a trusted environment.

This thesis project aims at exploring the challenges of sustainability within the segment of ski-helmets. It should lead to locating opportunities for transitioning them into the Circular Economy.

Ski-helmets are single-impact items, comprised of multiple different materials in inseparable product assemblies that prevent disassembly and recyclability. They are discarded after critical impacts, when safety critical parts fail. This also happens, when product parts with crucial perceived value deteriorate visually or fail to fit current fashion trends. Facilitating repair or refurbishment is currently obstructed through certifications and future developments seem promising but unsure. After discarding, helmets are not recycled, which leads to the loss of resources, energy and value.
Different ski-helmets were analysed on their ease of disassembly and their environmental impact using tools like HotSpot-Mapping, Disassembly Maps and Life Cycle Assessment. A survey and interviews were conducted for gaining insights into user-behaviour and expertise in ski-helmets and beyond.

The project’s outcome is a visionary concept for transitioning ski-helmets into the Circular Economy — the Airguard concept. The proposal includes a novel approach on energy-management, rather than using single-impact EPS-foam. A system of TPU air-vessels enables the absorption of multiple impacts and the structure can be easily restored through remanufacturing.

The Airguard concept is developed to fit into processes like recycling and remanufacturing. It is integrated into an assembly base with less different materials used, enabling product disassembly and improved access to parts with high impact, embedded energy and economic value — The priority parts.

The assembly base includes the possibility to change parts which subject to deterioration, like visors and soft-liners. Additionally, it provides a modular base for product add-ons and upgrades, increasing usability, flexibility and longevity.
After the product’s end of use, an incentive take-back system should enable retrieving used products to regain their value through recycling and remanufacturing.
As an intermediate step, the Eco-Savor concept was developed, focusing on recycling, while using the same assembly base as the Airguard concept, built around a core of trusted EPS. As a stepping stone, it should be used to improve product architecture and for gathering insights on part durability for later remanufacturing. A roadmap was developed to indicate development steps over the timeline of six years.

In the end, both concepts should stand as a vision towards sustainability, with many features to further explore and the possibility to gradually decrease environmental impact in ski-helmets.

Refurbishment is a critical strategy in the circular economy (Bocken et al., 2016). Despite the environmental and financial benefits, refurbished products are not a popular consumer choice (Mugge et al., 2017). Refurbished products are seen as old, used and of low quality, and consumers worry that products are contaminated with traces of a prior user (Mugge et al., 2017). This lack of consumer acceptance is perceived as too risky for companies to make the financial investments needed for refurbishment. In theory, refurbishment can be implemented in any product category. But, not every product category is equally popular. Partly due to the lack of consumer interest, the refurbishment of personal care products remains unexplored (Mugge et al., 2017). Because of this, many products and components go to scrap before the end of their functional life. To exploit this potential, consumers need to see the value of refurbished personal care products. To this end, this project has aimed to explore ways for designers to enhance the consumer acceptance of refurbished products through product design. This raised the question of how hygiene perception influences the will to buy refurbished. Hygiene is related to the consumer’s fear of contamination. Consumer interviews suggest that hygiene is mainly perceived in relation to complexity. Features like buttons, small corners, and split lines negatively influence the refurbished product’s acceptance. This suggests that product complexity negatively affects the perceived ease of cleaning. Findings also show that the colour white and smooth surface finishing are favourable for a refurbished product due to their associations with hygiene and medical products. From this research, it can be stated that improving the hygiene perception will cause a slightly increased willingness to buy refurbished. The research findings led to the following conclusion on the influence of design aesthetics on the acceptance of the refurbished product: ‘Aesthetics influence the acceptance via associations but will not be the deciding aspect for solving the overarching societal problem that stands in the way of refurbished product acceptance; misconceptions about refurbishment’. That does not mean that aesthetics have no influence at all. Creating positive associations through aesthetics can increase the willingness to buy refurbished (Huang et al., 2020). This project concludes that, for the Lumea, especially associations with luxury, hygiene and durability positively influence the acceptance of the refurbished product. Based on this redesign process, it was concluded that design for refurbishment is not a quick fix or stand-alone design activity. It is a mindset best developed through experience. Every product and context is unique. There are no guidelines or rules to follow, which apply in every situation. The proposed skills for designers to incorporate the refurbishment design mindset are (1) consumer empathy, (2) product lifetime management and (3) ecosystem thinking. To help designers to develop these skills, a tool was created in the shape of a canvas. Each box on this canvas focuses on a different aspect of refurbishment, ranging from the different consumers in different lifetimes to ideation on aesthetics features and concerns.

This project started with the following assignment: redesign the Adria Action caravan to fit in a circular economy and to have less CO2 emissions. However, the outcome of this project is not a redesign of a caravan but a framework for Adria to work towards (partial) circular As an example of the functioning of this framework, a redesign of the bathroom floor was done.To get to know the particular caravan and the caravan industry an analysis of the context was conducted. An eco-analysis on material basis of the Action caravan was done and visits to experts in the industry, repairmen and a caravan recycling company, were made. The main conclusions from the analysis were that the structural body has the most value, both economically as environmentally, and therefore needs to be used for a longer time. There already is an effort made but it is complicated due to components that are hard to repair and due to a lack of support and instructions and availability of spare parts. In the caravan industry and this company there is also little standardization which means there are a lot of unique parts. This makes it hard to find fitting components and to reuse perfectly good components in other vehicles. The successful business of repair and recycling companies shows that there is value after the sale of the caravan but it is made unnecessary complex to retain this value by the organization of the caravan companies.The framework shows that designing caravans for a circular economy involves more aspects than just redesigning the individual parts for reuse, repair and recycling possibilities. There are different levels on which actions can take place and to become completely circular, these levels must work together. First, analytical capabilities, such as LCA and hot spot mapping, are needed to assess the current condition of the caravans and evaluate improvements. To do this, a different way of documenting will be required within Adria. Next, with this objective way of assessing the caravan, focus points can be found and components can be redesigned using the circular economy ideals. Those adjustments can then again be evaluated.One of the focus points found is the bathroom floor. It is a critical part because it protects the frame from moisture, the bathroom is not functional without the floor and it is very difficult to disassemble and reassemble the floor. At the moment, the floor is being repaired with polyurethane, which restores the value of the caravan at that time, but the repair makes the component non-recyclable and therefore no longer part of the circular economy. It is more sustainable to replace the tray as a whole. So when redesigning the tray, it was looked at how this can be done easier. It requires minor adjustments to the part and larger adjustments at a company level. On a company level, some variables should be agreed on as a fixed standard. This makes future designs backward compatible and therefore makes it easy and cost-efficient to produce an extra part when a customer orders it, enabling the replacement of the tray.

This project focuses on how we can provide consumers with the right tools and the right knowledge so that they can take care of their coffee makers. The final outcome of this project is a toolkit that includes all the necessary items for maintenance and repair and a website to help consumers through the fault diagnosis process (i.e. help them find out what is wrong with their coffee maker).