To make electronic products fit for circular economy strategies such as life extension, refurbishment, and recycling, ease of disassembly is a key design quality. Several tools are available to assess the ease of disassembly of products during the design process, such as the ease of Disassembly Metric (eDiM) and Hotspot Mapping (HSM). The eDiM method uses the time-to-dismantle as a unit for calculating the ease of disassembly. The longer it takes to reach a priority part, the lower the ease of disassembly. Hotspot mapping scores the different parts in the product architecture and ranks them on its failure rate (priority parts), activity, time-to-disassemble, embodied environmental impact, and embodied economical value. These tools help designers prioritize which parts of the product need to be redesigned to improve its circularity. The eDiM tool is quick and easy to use but is based on generic proxy times, which may not be applicable to specific fastener designs or product types. On the other hand, the hotspot mapping tool uses actual recorded times to accurately identify disassembly hotspots. Recording the time-to-disassemble is more accurate, but is also more time consuming and depends on the operator's experience. Therefore it is difficult to come up with reproducible numbers. It is crucial to find the right balance for these tools, to be able to accurately identify hotspots while maintaining the usability. In this paper, we research how to develop product-specific proxy times in order to reduce the effort required for assessing hotspots. To reach our goal, we conducted a series of experiments to measure the actual disassembly times of different computer mice, and compared them with the predictions from eDiM. The results indicate that the tools provide accurate results for the most dominant fastener type used in this type of product (Phillips screws) but largely deviate from actual results for some other common fastening techniques, such as adhesives. Consequently, generic proxy times could not be used to correctly identify the product design hotspots. The authors suggest specific modifications to the ease-of-disassembly tools to improve their applicability, thereby supporting the design of circular electronics.

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Most products require a redesign to be viable in a circular economy. For instance, by implementing design for disassembly, remanufacturing, recyclability, and using long-lived components. Typically, different solutions can be chosen to improve a products' circularity, and different strategies can be aimed at keeping the product, its components, and materials in the loop. When developing products for a circular economy, designers and manufacturers want to assess their solutions and choose between alternatives early in the design process. This paper describes the Circularity Calculator, a tool that has been developed to help designers assess the potential resource circularity and value capture of products in the first design stages. The tool provides quantitative indicators that help determine whether and which circular strategies are potentially viable for the company. This paper discusses the methodology behind the Circularity Calculator, which uses four KPIs that have been developed for assessment; a Circularity indicator, Value Capture indicator, Recycled Content indicator and a Reuse Index. We will explain how the dashboard interface is used to model a linear and circular product system which can be compared on its economic potential. The tool is illustrated with an example concerning the analysis of a household blender.@en

Designing products for the Circular Economy requires closing and slowing of loops by means of repair, reman-ufacturing, refurbishment, parts reuse and/or recycling. Ease of product disassembly facilitates these processes to be more cost-effective, resulting in a better circular strategy fit. In this paper we present the Hotspot Map-ping method. The objective of this method is to help designers in (re)designing their products for ease of disas-sembly, by assessing which parts in the product architecture are most critical for ease of disassembly. Critical parts are parts with a high failure rate or maintenance need and/or with a high economic and environmental value, that should be easily accessible with low effort to enable cost-effective recovery processes. A product’s ease of disassembly is determined by factors that help or hinder the disconnection of critical parts from the rest of the product. The Hotspot Mapping method is a spreadsheet-based tool that indicates ease-of-disassembly by flagging five ‘hotspot’ indicators: (i) time needed to disconnect parts, (ii) difficulty of access, (iii) priority parts, (iv) environmental impact and (v) economy valuable parts. The Hotspot Mapping method adds to recent repairability assessment methods proposed in standards such as EN45554:2020, by also taking into account other aspects than failure-rate and functionality, such as economic and environmental value of the parts and materials. This paper describes the Hotspot Mapping method and applies the method to a household blender.@en

A timber guardrail made of sustainable tropical hardwoods has been developed in the Netherlands. The guardrail is an environmentally friendly alternative for zinc-coated steel barriers. The guardrail is made of a combination of two durable hardwood species: angelim vermelho (Dinizia excelsa) from Brazil and azobé (Lophira alata) from Africa. Full-scale tests have shown that the guardrail is able to withstand the impact of a 13000 kg bus driving at a speed of 70 km/h and an impact angle of 20° as well as that of a car of 900 kg having an impact speed of 100 km/h and same angle. Steam bent curved boards are used as energy absorbers from the passenger car impact. After the full-scale tests with the bus, no damage was found in the timber elements, and the guardrail had only to be straightened, saving repair costs during the service life of a guardrail. The guardrail fulfils the requirements specified in European standard EN 1317 Road Safety Systems for the H2 level with accident severity index of 1.0. @en

By combining the lessons learned from the four ResCoM industrial cases, a generic methodology was developed for other companies that want to engage in the development of multiple-lifecycle products. This report describes a stepwise approach for developing such products. The approach includes a suite of design tools as well as a practical case study example to illustrate the implementation in practice.@en

The Circular Pathfinder tool, which provides guidance to companies looking for appropriate circular design strategies, was developed based on OEM (original equipment manufacturer) case studies. Ease of use was one of the main requirements during development of the tool, resulting in a software-based guide that asks a maximum of ten product-related questions, after which it gives a recommendation for one or more specific circular design strategies. The advantage of a practice-based tool is that the practical relevance is, in all likelihood, high. The disadvantage, however, is the lack of scientific validation. This paper presents a literature review of the decision variables and heuristics of the Circular Pathfinder, with the aim to uncover any discrepancies between practice and literature. The main finding is that the focus on practical usefulness of the tool has led to excessive reduction of the complexity inherent in strategic circular design decisions. Recommendations for improving the Circular Pathfinder tool are given.@en

The transition within business from a linear to a circular economy brings with it a range of practical challenges for companies. The following question is addressed: What are the product design and business model strategies for
companies that want to move to a circular economy model? This paper develops a framework of strategies to guide designers and business strategists in the move from a linear to a circular economy. Building on Stahel, the terminology
of slowing, closing, and narrowing resource loops is introduced. A list of product design strategies, business model strategies, and examples for key decision-makers in businesses is introduced, to facilitate the move to a circular economy. This framework also opens up a future research agenda for the circular economy.
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BACKGROUND: Making a lightweight seat that is also comfortable can be contradictory because usually comfort improvement means adding a feature (e.g. headrest, adjustable lumbar support, movable armrests, integrated massage systems, etc.), which makes seats heavier. OBJECTIVE: This paper explores the design of an economy class aircraft seat that aims to be lightweight, comfortable and sustainable. METHODS: Theory about comfort in seats, ergonomics, lightweight design, Biomimicry and Cradle to cradle was studied and resulted in a list of requirements that the new seat should satisfy. RESULTS: The design process resulted in a new seat that is 36 lighter than the reference seat, which showed that a significant weight reduction can be achieved. This was completed by re-designing the backrest and seat pan and integrating their functions into a reduced number of parts. Apart from the weight reduction that helps in reducing the airplane's environmental impact, the seat also satisfies most of the other sustainability requirements such as the use of recyclable materials, design for disassembly, easy to repair. A user test compared the new seat with a premium economy class aircraft seat and the level of comfort was similar. CONCLUSIONS: Strong points of the new design were identified such as the lumbar support and the cushioning material, as well as shortcomings on which the seat needs to be improved, like the seat pan length and the first impression. Long term comfort tests are still needed as the seat is meant for long-haul flights.

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In the field of sustainable product design, the use of nature-inspired design (NID) strategies such as biomimicry and cradle to cradle has become more widespread, resulting in a variety of nature-inspired products. Research so far has studied NID on the basis of individual, key design cases and student projects. This paper assesses the state of NID at nine companies that have applied either biomimicry or cradle to cradle in product design. NID comes to the forefront as a promising but challenging new design paradigm. Analysis of best practice reveals that companies that applied a top-down approach, invested in training and/or external NID-experts, set positive and ambitious design targets, and included value chain partners early on in their projects were generally successful in removing barriers towards project success.@en