Conceptual framework for the design and development of sustainability-oriented products: toward EQUID 4.0

Abstract

The commitment to a more sustainable world in social and environmental terms requires product design and development (PDD) models that will help achieve this goal. Based on a dialogue between theory and practice, this paper presents the reflections that led to such a sociotechnical model, including its main principles: Ergonomics Quality in Design (EQUID) 4.0. It is grounded on a broad concept of ergonomics and human factors (E/HF), going beyond the traditional, narrow view of E/HF in PDD. EQUID 2.0 included the organisational dimension in the design process but left its role only in the immediate sphere of product design. EQUID 4.0 recognises that E/HF quality in the design process depends on a higher level, i.e. the organisation itself and integrates the contributions of preceding versions in an expanded E/HF concept: one that proposes that E/HF should always include not just the social but also the environmental dimension of sustainability.

THEORETICAL RELEVANCE

If a tool or method that aims to contribute to inserting E/HF into production spheres is to be proposed, there is a need to establish a conceptual framework derived from a dialogue between E/HF theory and practice in relation to quality, sustainability, and product design and development.

Keywords:

• Product design and development
• ergonomics
• quality
• sustainability
• sociotechnical systems
• stakeholders

1. Introduction

Ergonomics Quality in Design (EQUID) is an International Ergonomics Association (IEA) initiative aimed at helping the general public to make well-informed decisions about product quality from the E/HF perspective and to promote the integration of E/HF into the design process. The first version was constructed by experts on behalf of IEA and was the result of work that lasted several years (2000-2007). Feedback for this version, entitled EQUID Requirements in the Design Process (v.1.11), was sought from professionals, who gave the initiative a positive appraisal. A version entitled ‘Key requirements for the IEA EQUID process’ was published as an attachment in 2011 (Nael 2011). Based on the recommendations added to version 1.11, the proposal was adjusted and published on the IEA website (https://iea.cc/publication/) as EQUID 2.0 (2008), which is available as a guide in terms of what is stated as ‘Ergonomically Designed Product’ (Nael et al. 2008,. 1), with a view to ensuring that ergonomic principles are incorporated into the design process. Various publications consider it to be an effective tool for designing and defining ergonomic and functional product characteristics (Helander et al. 2015; Schlick, Bruder, and Luczak 2018; Cantele et al. 2021).

At the time the first version of EQUID was being developed, International Organization for Standardization (ISO) launched ISO Standard 9241:210:2010 (Ergonomics of human-system interaction – Part 210: Human-centred design for interactive systems) (ISO 2010), the purpose of which overlapped the EQUID initiative, to some extent. An Institute of Ergonomics and Human Factors team at the Technical University of Darmstadt (IAD) therefore worked on a new version, in order to establish a differentiation with respect to the ISO standard in terms of coverage and focus and with a view to drawing up a complementary document that differed from existing standards, designed for a wider audience, thus promoting greater access, especially in product/services developer spheres. Construction of this complementary document implied not just the development of a Delphi Study (Linstone and Turoff 1975) but also documenting and analysing study cases, and this inevitably gave rise to a questioning and expansion of EQUID 2.0. The resulting proposal was presented and published succinctly in 2014 (Lange-Morales, García-Acosta, and Bruder 2014) and is called Version 3.0. The contributions to this version included: (a) incorporation of the systemic focus; (b) concurrent environment-oriented engineering (Riba I Romeva 2002); (c) bringing product design and development (PDD) phases and processes closer in time by taking ‘Product Life Cycle’ (PLC), managed classically both in literature and in practice, as the preliminary benchmark; (d) differentiation between organisation-oriented requirements and design process-oriented requirements; and, finally, (e) the explicit and extended involvement of all stakeholders. Stakeholders include individuals, groups, organizations, or entities who have agency or who are affected by decision-making in the PDD process.

The full version of EQUID 3.0 was disseminated and applied mainly in Latin America between 2015 and 2021, both in postgraduate courses and at international events such as ABERGO 2016 (Belo Horizonte, Brazil). This process of applying the model practically in the education environment and discussing it with peers with expertise in international scenarios resulted in an opportunity to reflect on lessons learned from these applications. Moreover, the interest in contributing to a more comprehensive PDD that took on board not only social but also environmental sustainability justified developing a more robust EQUID, in line with the European Commission’s Industry 5.0 proposal, where not only ergonomic interests were incorporated into the traditional human and social approach but also the switch to considering environment-oriented values (Lange-Morales, Thatcher, and García-Acosta 2014), with an ethical posture adopted in the PDD that considers social and environmental matters symmetrically (Thatcher, Lange-Morales, and García-Acosta 2020).

This article presents a practical application-based, sustainability-oriented theoretical reflection on EQUID 2.0 and 3.0, and the principles deriving from that reflection which form the basis of EQUID 4.0, a proposal that evolves from a guide to the requirements for guaranteeing that E/HF is included in the product design process to a model for changing the product design and development culture, with emphasis on the fact that E/HF is not only useful for the social and economic sustainability of companies but also that it can contribute to environmental sustainability in the production system in general.

2. Epistemological and methodological approach

The E/HF discipline is built around relations between various general dimensions, including theory, practice and education, as well as design (Karwowski 2005). This work approaches the aforementioned dimensions from the perspective of the following principles. Firstly, the E/HF community (as expressed in IEA initiatives) wants to expand its impact in an already-complex world, which implies developing approaches that take this complexity into account. Secondly, the PDD process can be understood as a sociotechnical system, meaning that the E/HF contribution is no longer limited to product design as such (microergonomics), but rather integrates the organisational dimension (macroergonomics). And thirdly, it is recognised that one of the paths that E/HF will follow in the future lies in its contribution to sustainability (Karwowski and Zhang 2021), where some authors consider that E/HF should include not only the social and economic dimensions but also the environmental dimension (Hanson 2013; Lange-Morales, Thatcher, and García-Acosta 2014).

The development process for the EQUID 4.0 model has a qualitative – interpretative approach which establishes relationships between the requirements proposed in EQUID 2.0 for guaranteeing E/HF quality in the PDD process and the challenges that companies face in that process, with emphasis on two key aspects included in the European Commission’s Industry 5.0 proposal (2022): the human-centred approach, and sustainability (Nahavandi 2019; Alves, Lima, and Gaspar 2023). The former is a fundamental part of E/HF theory and practice. On the other hand, one dimension of sustainability, namely the environment, is still incipient in production organisations, despite awareness and work worldwide increasing all the time. The human-centred approach takes on board the values and requirements of all stakeholders, whereas the sustainability-centred approach involves rethinking the inclusion not only of the social dimension of sustainability but also economic and environmental sustainability, on the understanding that no economy is sustainable unless it recognises the limits of natural capital and human capital.

In methodological terms, one way that a discipline advances is through dialogue between theory and practice. This dialogue can be in the form of an iterative process that reflects on the practical application of models which, for constructive design research, is understood as prototyping (Koskinen et al. 2011). In line with this, the present work conducts an iterative reflection on versions EQUID 2.0 and EQUID 3.0, their relationship with successful PDD cases in multiple production realities, and the application of EQUID 3.0 in fifteen study cases. This reflection was complemented by a non-exhaustive, theoretical review which focused on key, predefined concepts (quality and sustainability), as well as emerging ones (complexity, uncertainty and coherence). By comparing the model with multiple realities, supplemented by these theoretical reviews, it proved possible to infer principles that are applicable to different scales and organisational conditions, thereby giving meaning to the EQUID 4.0 proposal. Figure 1 shows the chronological development of EQUID 4.0.

Figure 1. Chronology showing development of EQUID 4.0.

3. Aspects approached in the reflective dialogue between theory and practice

3.1. Systemic approach framework

There are various ways of looking at systems sciences, including approaches oriented toward developing ideas for systems and others that are oriented toward applying ideas for systems in specific disciplines (Laszlo and Laszlo 2003). E/HF is in the second group, with a sociotechnical focus (Hendrick and Kleiner 2002) and an orientation toward design (Dul et al. 2012) and toward innovation (García Acosta and Lange Morales 2011). In this systemic focus, EQUID is considered to be a potentially useful approach to the growing number of VUCA contexts (volatile, uncertain, complex and ambiguous) that characterise the world today (Laszlo 2018). EQUID, in the system innovation context, is a strategy for ensuring that PDD is aligned with the design of evolutional systems and which seeks to transform the challenging aspects of VUCA into an acronym that is consistent with a more prosperous world, namely vision, understanding, clarity and agility (positive VUCA, as Laszlo states), one that considers conscious transformation toward social and environmental sustainability.

3.2. Reflections on EQUID 2.0 requirements and quality

The EQUID 2.0 document was drawn up so that there could be a guide to obtaining an ‘ergonomically designed product’ (Nael et al. 2008, 1), with this concept deemed to refer to a product that is developed by following a process that incorporates ergonomic principles into the design process. To achieve this, it proposes five groups of requirements: (1) organisational management and documentation, (2) initial definition of user requirements, (3) design reviews, (4) final ergonomic evaluation, and (5) post-sale user satisfaction evaluation (Nael et al. 2008). With a view to acquiring a deeper understanding of these requirements and their relationship to product design and development quality, a series of questions was drawn up, so that those requirements could be organised in the model that is explained below. These questions corresponded, broadly, to reviewing EQUID requirements using the traditional ‘W’ questions (i.e. who, what, where, when and how), with a view to determining their relationship to actors, processes, and procedures in a more precise manner.

3.2.1. Quality

EQUID includes the word ‘quality’ in its own name. However, what does quality mean? According to the Oxford Dictionary, quality is defined as ‘the standard of something measured, with respect to other similar things; the degree of excellence of something’ (Oxford Dictionaries 2014). These two definitions imply two things: a relational aspect and a quality, which leads us to think that quality has a Janic face (from Janus, the god of duality, usually depicted as having two faces). It could also be said, in line with what Cakir (2000) states, that one face is relevant for people who use the entity, while the other face is important for those who have to ‘bring to fruition’ what users want. The former relates to a quality of the entity, whereas the latter relates to the process whereby the entity is developed.

3.2.2. What does quality mean in E/HF?

The next question that has to be answered is what quality means in E/HF. Dul et al. (2012) propose that high-quality E/HF should consider three aspects: having a systemic focus, being design-oriented, and focusing at the same time on performance and wellbeing (Dul et al. 2012). Based on this approach, and considering that IEA took these authors’ proposal on board as a strategy that should be implemented by IEA, ergonomic quality in design can be understood as the degree of excellence in dealing with ergonomic matters and human factors throughout a product development cycle, considering a systemic approach, having a design-oriented strategy, and focusing on both performance and wellbeing.

3.2.3. Who is responsible for quality?

Many people with different roles participate in the process whereby an idea becomes a product, and E/HF is just one of the factors that must be considered. The next question, therefore, is whose responsibility for quality in the management of E/HF matters, and this depends on when a product is being configured. To answer the question, it is necessary to take into account the fact that the E/HF matters that should be considered in product design and development are not restricted to an advanced stage of the process. Twenty years ago, Fulton Suri and Marsch pointed to the frustration that ergonomists felt when called on to provide feedback on design processes when project direction decisions had already been made, and they stressed the need for E/HF to be involved right from the earliest stages of the design process (Fulton Suri and Marsch 2000). Secondly, Genaidy, Karwowski, and Shoaf (2002) state that, given the technological advances in, and the increased complexity of, manufacturing systems, the whole organisation is responsible for the product. These two arguments lead to the conclusion that responsibility for quality in the management of E/HF matters in a product depends not only on the E/HF expert, but rather on everyone involved in the decision-making process for the product.

3.2.4. When and where should E/HF quality be considered?

The above conclusion provides a direct answer to the questions of when and where E/HF quality should be considered in PDD. If E/HF quality depends on everyone involved in making decisions, it should be considered in every stage of PDD, which means that the involvement of all stakeholders becomes a primordial matter.

3.2.5. How is quality achieved in PDD?

Finally, we come to the question of how E/HF quality is achieved in PDD. It is here that we can look more closely at the five groups of requirements proposed by EQUID and go back to the Janic face of quality referred to above. Organisational management and documentation is a requirement that is linked to organisational culture, whereas initial definition of user requirements, design reviews, final ergonomic evaluation and post-sale user satisfaction evaluation are requirements that are related to the design process. This distinction is of vital importance, because it shows that the proposed requirements belong to two distinct, albeit interconnected, processes, which results in a differentiation in terms of their nature and application. Organisational culture requirements (1) extend beyond the product design and development process itself and establish the framework and conditions for ensuring that the following group of requirements, relating to the design process (2, 3, 4 and 5), can be successful (see Figure 2). Without this framework, inclusion of E/HF and, hence, its quality, depend on the skill and commitment of design team members, and they are frequently undervalued, compared to other design variables.

Figure 2. Quality of E/HF in design and its relation to EQUID requirements.

In short, E/HF quality in product design and development is a quality that can be seen in the product designed and depends on two relationships: an organisational structure with a culture that recognises and supports the inclusion and management of E/HF in the design and development process, and a consistent understanding of user needs in the context of the intended use and the transfer thereof to design requirements, which are, in turn, incorporated into product design and development.

3.3. Sustainability and product socio-technological cycle (PstC)

EQUID 2.0 set out the key requirements for ensuring quality when applying E/HF in PDD processes. However, it does not include sustainability as a complementary and booster criterion. EQUID 3.0 concerns itself with ensuring that design processes achieve maximum quality by involving E/HF (and ergonomists as stakeholders) in strategic decisions that are made in each and every stage of PDD. EQUID 4.0 aims to view quality and sustainability as an interdependent coupling, since it recognises that quality cannot now be separated from the different dimensions of sustainability. Including in the time flow the different phases of PDD in the time flow, from the perspective of the product socio-technological cycles (PstC), means that an appropriate directing toward sustainability can be meshed in from the initial stage.

3.3.1. Sustainability and sustainable development

It is important to start with the question of what is understood by sustainability from its basic meaning (Oxford Dictionaries online (2022): The ability to continue or to be able to continue for a long time). It also relates to using natural products and energy, so as not to harm the environment. These definitions imply two reflections. The first is related to an awareness of surviving in time, and this, in turn, implies recognising our interdependence as a species on Earth, together with all other beings (Fisch 2017), as against the anthropocentric vision that results from the dominant modernity, which makes nature a mere resource for humankind’s civilising processes. Sustainable resource management is not enough, since there is a need to transition to a more participative and collective process that involves both scientific and non-scientific or ancestral knowledge, based, for example, on the ‘communicative action’ proposed by Habermas, which emphasises respect and agreements deriving from sociocultural diversity (Rist et al. 2007). The second reflection is linked to the need to recognise that the dynamics of the various beings that exist in nature, except for humans, tend to remain close to equilibrium, so that they can subsist, coexist, and not become extinct prematurely and of their own accord, because, in normal evolutionary conditions, living beings have no contamination cycles, but rather cycles of regeneration and co-nutrition. It is thus fundamental that we learn from nature and emulate it in its entirety, as biomimicry proposes (Benyus 1997), and not just formally and mechanically, as conceived in bionics; rather, by understanding that technology and nature, together with their philosophical and ethical implications (Riechmann 2006; Beith 2021), are not separate areas of facts and knowledge but, rather, new conceptions and understandings, as nature technology, that were explored, in the work of Oxman (https://oxman.com/) (Fisch 2017)), for example.

This implies that the EQUID 4.0 model needs to distinguish between sustainable development (Brundtland 1987), an approach that is primarily linked to economic growth, which makes it an oxymoron (Redclift 2005), and the broad, holistic view of sustainability as a decentralised notion of economics which recognises not only three classical dimensions of the triple bottom line and its subsequent models (Dyllick and Hockerts 2002; Mauerhofer 2008), but rather multiple dimensions, namely social, economic, environmental, technological, political and cultural sustainability (Lange-Morales, Thatcher, and García-Acosta 2014). The advantage of sustainability based on this multidimensionality is that it generates more elements of understanding and analysis for facing up to the current problems that have emerged, such as climate change (the global heating of Earth, a position we share as authors). Quite apart from the debate and its solution, it is clear that humankind needs to be conscious of, and consistent with, its ability to have a negative impact on biotrophic systems deriving from anthropic systems, such as systems for the extraction of resources and the production and configuration of products and services, which take it ever further away from ecosystem balance.

3.3.2. E/HF, sustainability, and sustainable development

No relationship whatever was established between E/HF and sustainability for many years. Although initial ‘human-machine’ models included the environment in which they operated and possible impacts such as noise, air quality or thermal conditions, this notion of environment referred solely to the aspects of the physical environment that Hendrick (2000) called human-environment interface technology or environmental ergonomics.

It is important to ask ourselves what sustainability means in E/HF. Thatcher et al. (2020) drew up a timeline for identifying E/HF responses to the challenges posed by sustainability. Three complementary perspectives were identified: (a) the contribution made by E/HF to social sustainability and its relationship to corporate responsibility (Zink 2008), (b) the emergence of ergoecology as a multidiscipline for systematically studying the relationships between human activities and natural systems (García-Acosta et al. 2014), and (c) the green ergonomics proposal as a concrete approach both to research and to implementing design-oriented interventions with a pro-nature approach (Thatcher 2013). In line with this, E/HF sustainability has traditionally been implicit, but only in the social and economic dimensions, with emphasis placed on the corporate scenario. However, recognition of the environmental dimension has been growing, with concrete contributions based on the design-oriented and systemic vision. When IEA formed the Human Factors and Sustainable Development Technical Committee (HFSD-TC) in 2008, it was a landmark for this recognition. Nowadays, this committee has the broader perspective of designing more efficient work processes and boosting social, technical and organisational innovations that will help us to face up to the major environmental problems (International Ergonomics Association [IEA] 2022; Thatcher et al. 2022).

3.3.3. Sustainability, design, and PDD

The next question that needs to be answered is who, from an E/HF-relational perspective, the involvement of sustainability-oriented proposal depends on, when PDD is approached. The answer is that the decision as to whether or not to address sustainability in a PDD process should be made when the initial intention of developing the product is determined, namely, in the vision stage (García-Acosta 2016). This premature involvement means that decisions can be made throughout the PDD process, based on the values and interests stipulated by the stakeholders. If this is not determined in the preliminary, vision stage, decisions could be made that are capricious or by certain stakeholders who take on leadership roles at tension points and where there are conflicts of interest. Thus, an ergonomist concerned about sustainability, for example, should make his or her position clear in feedback on the design processes and ensure that matters agreed upon in the sustainability vision are adhered to, as this will help to increase product/service quality. Now, as far as sustainability is concerned, stakeholder responsibility is collective, but it is qualified at the same time by the fact that the persons who represent the organisations and who, hence, have the most active political roles, are the ones that carry most weight when it comes to making decisions.

All of the above leads to the question of when and where sustainability considerations should be established. Firstly, as far as when is concerned, the situation is similar to that relating to quality: sustainability should be approached by all stakeholders from the start of the PDD process, with special emphasis placed on the first stage of the process, namely, the vision. Secondly, with respect to where, the starting point is the first stage (vision), but with constant verification in every stage of the PDD process, in order to ensure that the goals relating to sustainability are achieved.

In his message entitled ‘Meaning of Design toward the Future’, Yukari Nagai, as member of the editorial board of the International Journal of Design, Creativity and Innovation (IJDCI) (2013), draws attention to the fact that a creativity-oriented society model requires a redetermination of the meaning of design, from three perspectives: (a) the product design affinity; (b) the relationship between society and products designed; and (c) the legacy (IJDCI Editorial board 2013). As far as the legacy that Nagai mentions is concerned, there is no doubt that hopes of, and dreams for, better worlds are directed toward the future, but inevitably, now, toward a sustainable future where creativity, to give examples, stimulates the ability to rethink production models and new technologies, so that they are no longer oriented toward economic enrichment but toward serving the needs of all species that live on Earth. Creativity and innovation that serve creation and nature, rather than purely economic capital interests, are required.

Meanwhile, ecoeffectiveness, which is one of the fundamental notions for achieving sustainability, has been stated by some researchers to be utopic, since it proposes, discretely and without equivocation, that sustainability should be sought, without any possibility of it being done gradually, as is the case with ecoefficiency. A system or a product is ecoeffective if it has no negative impacts such as contamination, and, better still, if it generates positive impacts such as restoring biodiversity or nutrition within ecosystems. Before the concept was formalised by McDonough and Braungart (2002), authors like Frei (1998) had already shown where the path forward lay for designing eco-effective products, by seeking to close the loop or the weak relationship that existed between environmental management and sustainable product design. Frei (1998) stressed the importance of thinking of the product system as a whole and its permanent universe of relationships and complex interdependencies with the environment, envisaging, for example, the cycle of relationships between (1) defining the function, (2) modelling the product system, (3) the flow of materials and energy, (4) the resulting impacts on the environment, (5) measuring those impacts, and (6) analysing the cause of the said impacts and then feeding this information back to (1), thereby defining the function of the product system. This stresses the importance of integrated environmental product design and development management throughout what Frei refers to as relationships with the ‘product life cycle’ and all its concomitant processes. Meanwhile, Howarth and Hadfield (2006) developed a sustainable product design model at the University of Bournemouth, aimed at providing greater holistic coverage, such as waste, end of life and ethical posture, and characterised, on one hand, by the active integration and participation of all stakeholders and, on the other hand, by ensuring a co-evaluation of product design impacts by documenting and grading (high, medium or low) the risks, benefits and opportunities of all PDD topics throughout a cycle, based on three focal points of sustainability, namely social, economic and environmental.

Karlsson and Luttropp (2006) emphasise the fact that eco-design prioritises both human sustainability and business. This limits the perception of sustainability to an anthropocentric state. However, they are correct in stating, on the one hand, that design specifications and objectives which aim to achieve high levels of sustainability take priority over thinking of eco-design tools. On the other hand, they stress the need to involve all stakeholders in visualising and forming more sustainable societies. However, they conclude with two unfortunate ideas. The first is linked to the modernity paradigm, where the market is unquestionable and design is subject to that. The second is to favour the anthropocentrism of lifestyles and the deception of dematerialisation without thinking of energy demands for services. Nevertheless, their third conclusion is understandable and of vital importance, since ecoefficiency, by thinking about reducing impacts, loads and consumption, has replaced the radical commitment that implies designing ecoeffective products, processes and materials. Their final conclusion is that it is not clear what sustainable development is, which reveals that they do not understand the paradox and the oxymoron that surround sustainable development when they suggest that we should go on progressing and wait to see what happens, so that we can learn from it.

The sustainability paradigm and sustainability models have traditionally concentrated on three dimensions, namely economic sustainability, social responsibility, and environmental sustainability, with economic sustainability being not only predominant but also the only project or investment viability benchmark. However, it has been shown that the availability of natural capital, in the form of natural resources (renewable and non-renewable), is the only real way (Mauerhofer 2008) to define growth limits, boosted, among other things, by PDD. The substantial dimension is therefore environmental sustainability rather than economic sustainability, which is dependent on natural capital. Now, in addition to the hegemony of economic sustainability, there is also the fact that other sustainability dimensions tend to get forgotten, yet when these are considered, they enrich the conceptual perspective. An understanding based on sociotechnical systems should be complemented by the overall sustainability perspective.

3.3.4. Product sociotechnical cycles (PstC) as an alternative to structuring the framework

Finally, if we are to enquire into the PDD-centred conceptual framework, we need to answer the question of how a synergic relationship can be achieved between E/HF and sustainability in PDD. The answer implies prioritising not only the market and technical matters, as Product Life Cycle (PLC) (Cao and Folan 2012) traditionally does, but also more holistic approaches, such as the product sociotechnical cycles (PstC) proposal (García-Acosta and Lange-Morales 2020). On the one hand, PstC are based on sociotechnical systems (Trist and Bamforth 1951), which E/HF recognises as part of its conceptual framework because a sociotechnical system can consist of, and be as simple as, one person using a mechanical tool, or as complex as a multinational organisation (Hendrick and Kleiner 2002). On the other hand, PstC also envisage multidimensional sustainability which, in addition to the social, environmental and economic dimensions, includes technological, cultural and political sustainability (Lange-Morales, Thatcher, and García-Acosta 2014). Every company or human project that takes resources from nature and transforms them into something else (i.e. work, activity or artifacts, mentifacts and sociofacts) (Vidal 2002), should be a subject for E/HF and can be understood and analysed as a sociotechnical system.

PstC proposes seven major stages: vision, concept, design and development, production, marketing (including logistics) and incorporation, use and services, and disuse and support. It is determined at the vision stage whether or not the sociotechnical status of a PDD process will assume environmental responsibility. Three categories of relationship with other biotrophic cycles and systems are accordingly recognised: (a) relationships with other systems that do not consider sustainability or the ecoefficiency and ecoeffectiveness perspectives; (b) relationships with other systems oriented toward reducing negative impacts, energy wastage or the recovery of waste (in other words, focused on ecoefficiency); and (c) the positive relationship with any other system that considers not only generating zero impacts but also going beyond that by restoring and recovering resources and biodiversity from biological and technological metabolisms – in other words, oriented toward ecoeffectiveness (García-Acosta 2016; García-Acosta and Lange-Morales 2020).

3.4. Practical application of EQUID

With a view to understanding how ergonomic decisions are made in PDD and how E/HF can have a bearing on PDD challenges, four successful prototype case studies relating to the incorporation of E/HF into different scenarios were analysed, and this resulted in what is proposed in version EQUID 3.0. Subsequently, analysing the application (prototyping) of this version in fifteen study cases of graduate students’ professional projects made it possible to contrast how the proposal operated in a diverse real-world context, as pointed out by Joseph (2004).

3.4.1. Analysis of successful prototype case studies

The successful benchmarks were diverse in nature. The first was the design and development of the Opel Insignia 2009 vehicle, the first car to be developed on the basis of Product Profiling by the Opel/General Motors multinational, in Germany. This vehicle was the first mid-range car to win the ‘Car of the Year’ award, as well as many others. According to the Human Vehicle Integration team leader (M. Vogler, personal communication, 2011), a large part of this success could be put down to E/HF management in the design process. The second case was the Legrand/Bticino S.p.A. product design process, headed by one of the experts who took part in the initial EQUID proposal, Lina Bonapace (personal communication, 2012). The third benchmark was the design process for an ischiatic support for a metro station in the city of Medellín, Colombia (Sáenz and Valencia 2012a 2012b), an item for use by the general public where the design was headed by a university institution that followed the User-Centred Design concept (García-Acosta et al. 2011). Finally, a preliminary version of the model was contrasted with the general PDD process carried out at the multinational Dräger AG & Co., an entity that is engaged in the design of medical equipment and which incorporates high ergonomic and usability standards into its PDD process. Table 1 summarises the main characteristics of the analysis.

Table 1. Main characteristics of the analysis of the prototype case studies.

	Case 1	Case 2	Case 3	Case 4
Institution / Company	Opel / General Motors.	Le Grand Biticino.	Pontificia Universidad Bolivariana.	Dräger GmBH.
Product type*	Consumer product.	Interactive systems.	Consumer product.	Consumer product / interactive systems.
Focus of the analysis	Design and development of the Opel Insignia 2009.	General design process used by the company.	Design and development of a isquial support.	General design and development process used by the company.
Study conditions	In-depth interviews with the leader who set up the process in the company. Audio recording, transcription and verification of the leader. Subsequent analysis.	In-depth interview with the consultant who led the process in the company. Audio recording and subsequent analysis.	Analysis of published papers. In-depth interview with the leader of the process. Audio recording and subsequent analysis.	One day workshop carried out in the company with the participation of key stakeholders. Audio recording and subsequent analysis.
Key questions and issues addressed	What the PDD process was like; who was involved and when; how decisions were made; what were the biggest challenges; what methods were used.

* Based on ISO 9241:11.

3.4.2. Application of EQUID 3.0

The fifteen study cases applied EQUID 3.0 in different types of products, as referred to in ISO 9241:11 (2018), namely consumer products (5), systems (4), interactive system (1), services (2), and constructed environments (3) (Pérez Paredes 2021). Unlike the prototype case studies used for developing EQUID 3.0, the analysis of these cases enabled the proposal to be contrasted with the production and organisational reality of a wide range of organisations, from multinationals to individual undertakings, where E/HF were not necessarily considered to be an important factor. In all cases, in-depth interviews were conducted, establishing three premises of enquiry, including (a) how well the proposed PDD phases matched the actual process carried out in the companies; (b) how well the requirements associated with E/HF management were applied in the PDD; and (c) which requirements for the understanding of user issues were considered. Analysing a wider range of diverse products in different contexts meant that the strengths and weaknesses of the proposal could be understood.

3.5. Matters relating to uncertainty, complexity and coherence

The analysis both of successful prototype case studies and of the application of EQUID 3.0 in the fifteen study cases led to three matters being inferred that are highly relevant because they appeared as common denominators in PDD, namely uncertainty, complexity, and coherence, and this resulted in the following theoretical review in a PDD dialogue.

PDD is a process in which a large number and great variety of elements and stakeholders come into play, such as values, resources, contexts and knowledge. Developing a product in a multinational company is not the same as if a small business does so, nor is working in an industrialised country or an agricultural country the same thing. However, despite the differences that can be seen in different organisations and contexts, three matters have been inferred that have a characteristic common denominator in the PDD process analysed by EQUID: uncertainty, complexity, and consistency. This is the conclusion that was reached in EQUID 3.0, after conducting a deductive analysis of benchmarks and study cases by means of in-depth interviews. After reviewing the theory of various authors who deal with these matters in greater depth, it was decided to change the notion of consistency and replace it with coherence. Guaranteeing E/HF quality throughout PDD is one way of contributing to the handling of these matters, by identifying transverse elements that are decisive when it comes to the design of the model, and they will be presented later as the six principles of the model.

3.5.1. Uncertainty

De Weck, Eckert, and Clarkson (2007) classify PDD uncertainty as endogenous or exogenous, according to the source, as do Han et al. (2020). However, internal classifications differ. For de Weck and assistants, endogenous uncertainties include product context (technology, durability, reliability and non-modelled interactions), corporate context (strategy, maintenance contracts and contractual arrangements), and also the use context. Han et al. (2020) point out that both exogenous and endogenous uncertainty have random uncertainty and epistemic uncertainty characteristics. This latter, in turn, is divided into data uncertainty (rough uncertainty) and descriptive (or diffuse) uncertainty. According to these same authors, exogenous uncertainty includes the market, requirements, technology, and standards and regulations, with requirements being the most important exogenous uncertainty. These requirements combine both user requirements and the requirements of the remaining stakeholders, both of which are of primordial importance for E/HF and sustainability.

PDD uncertainty is used for expressing both the likelihood of certain design conjectures being incorrect and the presence of facts that are completely unknown and could influence the future state of a product, as well as its success on the market (de Weck, Eckert, and Clarkson 2007). Uncertainty is related, first and foremost, to having or not having information for making decisions throughout the PDD process. Secondly, it is associated with conditions which, although uncontrollable, are foreseeable, which means that the performance of the products/services in the future can be foreseen, for example by constructing prospective scenarios.

In the first case, it is important to start from the idea that uncertainty has many meanings, depending on the scientific domain in question, and it is directly related to the notion of entropy in thermodynamics. It has two meanings in the field of communication and information. On the one hand, there is the meaning put forward by Brillouin around 1951 that is called negentropy (loss of information increases entropy). On the other hand is the proposal put forward in 1948 by Shannon, for whom excessive information is the same as entropy. Both conceptions are valid, but they have opposite perspectives with respect to the certainty – uncertainty relationship. For Brillouin, it is possible for all information to produce order and tend toward certainty, whereas for Shannon, an excess of information leads to uncertainty (Hayles 1990). If we follow Brillouin’s perspective during PDD, obtaining more information for making decisions means that we will reduce uncertainty. But if we follow Shannon’s perspective in PDD processes, the excess and saturation of information can overcome the ability to process and understand it, thereby affecting decision-making. This establishes a kind of range of action where care has to be taken with the quantity and quality of information for each PDD phase; in other words, it should be reliable and consistent, all aimed at reducing uncertainty, but, at the same time, an awareness is needed that excessive information that cannot be interpreted could lead to uncertainty. Working with ranges of uncertainty has to be accepted in PDD processes, as does the fact that this uncertainty will gradually decrease as the process advances, but the uncertainty should be at a level that is manageable for design teams, administrators, producers, marketers and consumers/users.

In the second case, the uncertainty related to uncontrollable conditions tends to be dealt with nowadays not in merely probabilistic terms oriented toward certainty but by constructing various scenarios based on future studies. Probable futures are frequently constructed by using use scenarios (Fulton Suri and Marsch 2000), where technologies can be projected toward future technologies. This process enables new solutions to be developed to meet human needs and demands. Each product has a different technological evolution. Now, user facts, and in this case expectations in all possible dimensions (physical, cognitive, emotional and even spiritual), need to be taken into account in every prospective exercise. The physical dimension tends to be more predictable in a timeline. On the other hand, cognitive, emotional and spiritual dimensions tend to undergo bigger transformations, both locally and globally. Tools like ethnographic studies and the participative construction of future scenarios are effective for dealing with cognitive, emotional and spiritual matters, thereby reducing uncertainty.

3.5.2. Complexity

PDD is a complex process. According to Mol and Law (2002), complexity occurs when things are related but do not add up, events occur not necessarily in a linear process, and phenomena cannot be mapped in terms of a single set of three-dimensional coordinates. From a systemic viewpoint, complexity occurs not only due to the quantity of causally-linked elements but also because of the feedback processes that are generated when decisions are made (Andrade Sosa et al. 2007). Many matters need consideration in PDD, including technical, economic, human, logistic and commercial ones, among many others. Each of these factors is promoted and boosted by different stakeholders and then administered and decided on by different agents, who have different roles. Each of these stakeholders speaks its own language and each agent is responsible for making the best decision, based on his specific skill. The problem lies in the fact that the best solution for one matter is not necessarily the best for another variable, and conflicts frequently arise when decisions have to be made. However, these conflicts can be settled successfully when all stakeholders understand that they are part of a system and when all agents are clear about their common goal, based on continuous agreements to deliver a successful product that is in accordance with the guidance established by the organisation.

Complexity is equivalent to the number of different elements that have to be dealt with simultaneously by an organism or organisation in a constant process of construction and emergency (Thompson 2004). Therefore, the more complex the matters to be considered in PDD are, the more stakeholders are involved and tensions increase because of the diversity of interests and postures. And, as a result, the complexity will be greater when decisions are made. This necessarily implies dealing with different languages, which leads to the need to translate from one language to another, in at least two directions. On the one hand, user needs should be translated from a vague or emotional description into a technical language that can be incorporated into the functions, structure or materials of the product, thereby enabling each characteristic to be measured and verified using checking and verification processes. Similarly, the technical characteristics of the final product should be translated again into a language that the user can understand.

On the other hand, parties involved in PDD should bring their knowledge and expertise into line, in order to make the product socio-technically viable, which implies recognising the importance of the values that guide the design, of all matters that play a role, and of the negotiating limits for each variable. According to Gibbons and Nowotny (2001), knowledge and expertise are transgressive, which means that there is a need to generate a language that transgresses the limits of each expertise like a silo and takes on board the codes of other areas. In other words, dealing with the complexity of PDD means passing to a transdisciplinary approach, one where a communication is established that overcomes the particular codes of each language. Participative ergonomics and participative design, among other approaches, are thus a potent tool for achieving this.

Complexity is also part of the structural dimensions of a work system (Hendrick and Kleiner 2002) and every PDD occurs within an organisation, which necessarily implies that such a system exists. The variables that are a part of the complexity of a work system include integration, which includes communication, coordination and control. If complexity is manged successfully, it helps to reduce uncertainty, and in order to achieve this, stakeholders have to reach a consensus, not just in part of the design process but throughout the entire product cycle. Now, if this consensus is to be achieved, strategies are needed that will simplify and facilitate integration processes both within the organisation and with stakeholders outside the company, and with emphasis placed on the user, albeit not exclusively. Within the organisation, the human factor, which is deemed to include all persons involved in the PDD process, is key to understanding the needs and expectations of the people who will use the product designed.

3.5.3. Coherence

The third matter identified initially was consistency, which came to be understood as coherence and stability when making decisions throughout the PDD process. It is directly related to product design goals and requirements, and to the capabilities and resources available in the organisation. It is therefore related to time. Developing a product can take anything from a couple of months to several years, depending on its complexity, and the challenge therefore lies in guaranteeing that requirements and parameters established in early stages of the process will enable E/HF quality to be consolidated and maintained throughout the entire PDD process. This requires strategies for checking that decision-making processes ensure that each ‘yes’ or ‘no’ given to a design variable, parameter, alternative or characteristic is always in line with the goal of the project and the product as the different stages are passed through.

Decision-making has been of interest in economics, management and psychology for centuries. This article limits itself to decisions that are made in the field of PDD, since it is deemed to be a primary component when it comes to solving problems (Mosier and Fischer 2010) relating to accepting what one person wants and rejecting what someone else does not want (Loup-Escande et al. 2010). When decisions have to be made as a group, a consensus is achieved not only by allocating scores and classifications to the alternatives (Roberts 2008, quoted by Loup-Escande et al. 2010), but also based on the experience and knowledge of the participants, the presentation and argumentation skills and capabilities of those who explain the alternatives, and the role, ability to convince and power of each stakeholder. All this means that the complex individual and collaborative processes have to be consistent and, above all, to be seen to be coherent. Decision-making is a critical process in PDD because, in systemic terms, it plays a valve role – in systems language – with repercussions that could lead to a product being a success or a failure. In other words, decisions regulate the flow by accelerating, dividing or reorienting the PDD process.

The challenge facing coherence in PDD linked to E/HF lies in not sacrificing user requirements in order to meet other requirements such as cost or style, for example. Given that PDD is dynamic and that circumstances change, teams should continually adapt, which leads to plans that were appropriate at one point being inadequate later (Mosier and Fischer 2010). The process should even show the interests of the roles played by each stakeholder, but not personal interests. People can therefore change but design goals should be maintained over time. This is even more challenging when sustainability is approached in an overall manner, since biodegradable raw materials, for example, tend to be more costly, in financial terms, due to the fact that non-biodegradable ones tend to be subsidised under market rules of the game and therefore seem to be cheaper. Anyway, computer tools exist, as well as joint work platforms, to facilitate the decision-making process from different angles, so that coherence can be a documented consequence (Loup-Escande et al. 2010; Østergård, Jensen, and Maagaard 2016; Christensen and Knudsen 2010).

Company personnel consider it strategic to integrate skills for sustainability, but in the future rather than as a present priority, and to limit themselves, for example, to the selection of materials and energy efficiency (Schulte and Hallstedt 2017). This short-term thinking leads to decision-making coherence being biased toward just the economic dimension, namely costs, thereby affecting the sustainability vision. Three recommendations by these authors can be stressed: creating a shared understanding of sustainability, balancing short- and long-term perspectives, and educating and training people (Schulte and Hallstedt 2017). Following this same line of thought and with ecodesign, Pigosso, McAloone, and Rozenfeld (2015) also stress the importance of a common language and having a shared vision. Implementing the above strategies, recognising people’s abilities in organisations and working to boost them all contribute to coherence when decisions are made.

4. EQUID 4.0 principles

Before presenting the principles of EQUID 4.0 and in order to facilitate a visualisation of the differences and relationships between the different versions of EQUID, Figure 3 compares the graphical schemes developed for versions 1.11, 2.0 and 3.0.

Figure 3. Basic diagrams taken from Nael et al. (2008) and Lange-Morales, García-Acosta, and Bruder (2014). EQUID versions 1.11 and 2.0 maintain the same outline and elements, formalised in what they call required documents (1 to 5), but only include 2 to 5 in the diagram. EQUID 3.0 takes the requirements of EQUID 1.11 and 2.0, including not only those related to the design process, but incorporating graphically the requirements related to the organisation (organisational management and documentation). in addition, it specifies the phases of the PDD, as well as the involvement of all stakeholders and not only end-users.

The principles of EQUID 4.0 are outlined on the basis of what has been stated conceptually above. Table 2 details the main elements inferred in the analysis of the practical study cases (uncertainty, complexity, and coherence), with each of the principal proposals.

Table 2. Relationship between matters identified in PDD practice and EQUID 4.0 principles.

Principles	Reduction of uncertainty by means of	Understanding of complexity by means of	Contribution to coherence by means of
PDD is situated.	Recognition of user, stakeholders and the organisation.	Consideration of multiple variables and the relationships between them.	Verification of decisions in existing conditions.
PstC acts as a structural axis.	Identification and implementation of each stage.	The excess/deficiency of information relationship and the classification of variables.	Feedback in and from any phase. Understanding space/time relationship in the entire PDD.
EQUID requirements are differentiated	Differentiating between organisational variables and design process variables.	Recognising conflicts between variables when decisions are being made.	Consensus, despite diversity of postures, interests and values.
Ecoefficiency or ecoeffectiveness	Observation of scales and inter-dependencies.	Verification of complexity – transition relationship on the PDD path to local/global sustainability.	Identification of materials and energy interdependence as per location (geopolitical).
Importance and agency of stakeholders.	Constructing common languages and targets.
	Respect for, recognition of, and openness when communicating goals, values, interests and concerns during PDD.	Consideration of different postures and making decisions that fairly recognise the importance of design variables.	Improvement of communication between stakeholders, which facilitates decision-making.

4.1. PDD is a situated process

Firstly, PDD is a process in place, meaning that it requires a social organisation which is usually an undertaking, a company, an institution, a network, or a community. In other words, a PDD process is not something that happens ‘in the air’. The organisation therefore has a series of sociotechnical dynamics and characteristics that make it what it is, as a result of a series of values, a context, a project, a journey, and some concrete resources.

4.2. PstC acts as a structural axis

Although PDD involves a series of stages that can vary significantly from one product to another, all of them can be located in the PstC, in order to ensure that decisions relating to technical, social and environmental requirements are fair in a given time and space, since the sociotechnical and environmental orientation is established from the vision right through to final disposal. It also enables stakeholders to be clearly located throughout the entire project -thereby facilitating documentation and tracking when decisions are made- from the values and principles defined in the vision to decisions relating to the destination of the project after it has completed its existing cycle.

4.3. EQUID requirements are differentiated

The requirements for guaranteeing E/HF quality and sustainability in PDD can be divided into two: those that relate to the organisational culture, and those that relate to the design process itself. The first group of requirements, organisational management and documentation, is part of the organisational culture, while the other four groups of requirements refer to the design process.

4.4. Ecoefficiency or ecoeffectiveness

A sustainability-oriented PDD follows two possible paths. The first one is to be guided by ecoefficiency: in other words, doing more with less and reducing negative environmental impacts, but recognising their limits. The second path is to seek ecoeffectiveness, which implies nourishing and reinstating resources taken from nature, without generating waste. In either of these cases, it is at the vision stage that the decision is made and, if it is to be really sustainable, the ultimate end is ecoeffectiveness.

4.5. Importance and agency of stakeholders

Quality and sustainability-oriented requirements can be located throughout the PstC and, if they are to be met, the different stakeholders need to participate. It is important to recognise that when stakeholders make effective decisions, they become actors who are able to get involved and affect the PDD process. The E/HF specialist must, inevitably, be a stakeholder and agent of change who looks after users and takes part when strategic decisions are going to be made. E/HF should care not only for the user and artefacts but also for what happens with all stakeholders, organisationally-speaking.

Figure 4 illustrates the principles described above.

Figure 4. Basic diagram of EQUID 4.0, locating its five principles: (1) PDD is situated; (2) PstC acts as a structural axis; (3) EQUID requirements are differentiated; (4) Ecoefficiency or ecoeffectiveness; and (5) importance and agency of stakeholders.

Finally, Table 3 sets out EQUID 4.0 principles, with the proposed interdependent quality-sustainability coupling.

Table 3. Relationship between matters identified in PDD theoretical matters and EQUID 4.0 principles.

Principle	Importance for E/HF quality	Importance for sustainability
PDD is situated.	The sociocultural and technological characteristics of the user and of the company and all stakeholders should be recognised.	The geographical characteristics and the practices that exist both where the product is generated and where it is used should be recognised.
PstC acts as a structural axis.	It favours recognition of values and stakeholders, and the making of fair socio-technical and environmental decisions.
	It facilitates the documentation and tracking of decisions that are made.	It facilitates product orientation from the early vision stage.
EQUID requirements are differentiated.	A distinction should be made between requirements which affect organisational culture matters and those that affect PDD matters.	In the organisational culture, training and conviction about sustainability. In PDD, reduction in or non-generation of negative impacts.
Ecoefficiency or ecoeffectiveness.	It provides certainty in the orientation of PDD and the decision-making process.	Visualization of company orientation and its transition toward the future.
Importance and agency of stakeholders	Persons act as a function of their knowledge and their values.
	Those who take part in PDD should understand not only the user but also the remaining stakeholders.	Those who take part in PDD should understand and consciously share the company’s orientation.

5. Discussion

Proposing an environmental sustainability-oriented sociotechnical model for PDD that is based on E/HF could seem ambitious and even unrealistic, since proposals in the field of design for sustainability have existed since the nineties (Ceschin and Gaziulusoy 2016). The same could be said of user-centred design, where there are not just proposals but even standards, such as ISO 9241:210:2019 (Ergonomics of human-system interaction – Part 210: Human-centred design for interactive systems), or ISO 6385:2016 (Ergonomics principles in the design of work systems). Nevertheless, the fact that proposals and standards exist which are aimed at design for sustainability or that approach design (and indirectly quality) in PDD does not mean that proposals based on E/HF cannot be made, especially when it is recognised that they can contribute much more than the traditional, generalised view of microergonomics, reduced to the physical or cognitive. The recent IEA publication ‘Giving your business the human factor edge’ (IEA 2022), which seeks to ensure that corporate strategic directives understand that E/HF does much more than make individual contributions, such as selecting a chair, is a clear step in the same direction: the importance of macroergonomics, sociotechnical systems and systemic ergonomics has increased dramatically (Waterson and Robertson 2022), and work should be done to introduce these into other areas. In that sense, EQUID 4.0 can serve as a framework for linking fields for sustainability-oriented design that consider the complexity of the real world.

Ceschin and Gaziulusoy (2016) propose an evolutionary framework where approaches to design for sustainability are mapped and four levels of innovation are identified: (a) product, (b) product-service system, (c) spatio-social, and (d) sociotechnical system (Ceschin and Gaziulusoy 2016). EQUID 4.0 can be categorised in this evolutionary framework as a proposal in the final level, namely, sociotechnical system innovation.

Meanwhile, Muriel Guisado and García Acosta (2019) also conducted a systematic review of methods and tools with an environmental approach, albeit not restricted to design but covering all stages of the product existence cycle and complemented by a Delphi study. These authors concluded that, despite the many contributions that exist (methods, tools, software), there are ontological and epistemological gaps that hinder the identification of differential conceptual trends in environment- and sustainability-oriented design. Moreover, despite the fact that all the experts who took part in the study agreed on the importance of including the human being as a stakeholder, this is reduced to seeing him, paradigmatically, as a simple consumer or customer, in the best of cases (Muriel Guisado and García Acosta 2019). In short, EQUID 4.0 breaks this asymmetry and proposes that human and environmental factors be considered in parallel, within a sociotechnical approach, thereby increasing the possibility of more comprehensive and holistic interventions that will better meet the challenges of PDD.

Now, it is important to recognise the limits of the study and of the principles proposed in EQUID 4.0. Firstly, the case studies focused on existing products, so the principles would need to be tested in new developments. Secondly, although it is based on the systems approach, the theoretical-practical reflection did not consider emerging matters in the field of design and E/HF like cross-scale interactions, as treated in ecosocial systems (Lemke 2000; Baumgärtner 2008), or complementary epistemological approaches like the theory of practices (Reckwitz 2002), to mention just two approaches. There are works based both on E/HF (Lange-Morales 2022) and on design for sustainability (DfS) (Bhamra, Lilley, and Tang 2011; Kuijer 2014; Lockton, Harrison, and Stanton 2010) that already integrate these approaches and could help to reinforce the proposal.

6. Conclusions

E/HF quality in product design and development (PDD) is a quality that can be seen in the product designed and which depends on two relationships. The first relationship is with the organisation into which the PDD is inserted, where there is a need for the organisational culture to recognise and support the inclusion and management of E/HF in the PDD process. The second relationship refers to a consistent understanding of user needs in the intended use context and the translation of these needs into design requirements which, in turn, are incorporated into the PDD. The success of the EQUID 4.0 proposal therefore lies in understanding it as a proposal for a change in organisational and design culture, rather than as simply a method or a tool.

The conceptual elements of EQUID 4.0 were defined, and these include a systemic focus that takes on board dynamics and relationships, PstC as a structural axis for the model, E/HF involvement throughout the PDD process based on the incorporation of EQUID 2.0 requirements in a differentiated manner into the organisational culture and the design process, integration of the E/HF specialist as a stakeholder when strategic decisions are made, the inclusion of sustainability in all its dimensions, and recognition of the organisational identity as the basis for understanding and applying the model.

The interdependent quality-sustainability coupling proposed for EQUID 4.0 increases and expands the E/HF perspective in the design process by offering an approach that is easier to incorporate at strategic level into organisations that do PDD.

E/HF in PDD cannot concentrate solely on user requirements, since it is the agency of the stakeholders that ultimately defines the result of the product design. E/HF specialists should therefore be empowered in both their macro (organisational culture) and their micro (design process) strategic role.

Sustainability can be understood in two ways. Firstly, it should be seen in the PDD process as a goal to be achieved, which is not absolute, but relative and dependent on stakeholder interests and agencies. Secondly, it is a quality or attribute, when looking at the direction and outcome achieved after its existence and deployment as a product or service. As a target and a process, it is defined from the start of the PDD proposal and which, by working on the product sociotechnical cycle (PstC) concept rather than the hegemonic product life cycle (PLC), increases the possibilities of dealing with social and environmental matters that are defined on the basis of stakeholder values and interests.

All of the above means that EQUID 4.0 is a strategy which, if PDD is conceived as an evolutionary system, can contribute to overcoming the vision of sustainability as utopia and focus on system design as protopia (Laszlo 2018). A protopia provides practices, pathways and eco-systemic designs for a desirable future that can be realised with the conditions and potentials available to us now (Luksha et al. 2017).

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Additional information

Notes on contributors

Karen Lange-Morales

Karen Lange-Morales is full time professor at Universidad Nacional de Colombia. She studied industrial design at Universidad Rafael Landívar and Iberoamericana University and has a PhD in Public Health, focusing on the complexity of the use of medical devices in healthcare institutions. During the development of her doctorate studies, she worked as research associate at the Technical University of Darmstadt. Her working areas (teaching and research) include organizational ergonomics, systems thinking, design project, ergonomics quality in design and sociomaterial practices. She has also worked as a consultant in ergonomics and design at public and private sectors including farming, oil, manufacturing, education, banking, and food areas among others. Karen is member of MIMAPRO Research Group and has several publications in renowned journals and books. She is also co-founder and editor of ACTIO – Journal of Technology in Design, Film Arts and Visual Communication.

Gabriel García-Acosta

Gabriel García-Acosta is full time professor at Universidad Nacional de Colombia. He studied industrial design at Universidad Nacional de Colombia, has a magister in design and ergonomics from the National Autonomous University of Mexico, and received his doctorate in project engineering and innovation at the Universitat Politècnica de Catalunya · BarcelonaTech. He leads the design observatory ‘water and energy’ and his current research interests are oriented towards participatory design, transitional design, ergonomics and sustainability, sociotechnical systems, and ethics. He has also worked as senior consultant in ergonomics for several productive sectors (banking, farming, oil industry, health, manufacturing among others). He is co-founder of a 23 years old private company dedicated to design and ergonomics (Ergofactos SAS), co-founder and leader of MIMAPRO Research Group, and co-founder and member of the Colombian Society of Ergonomics. Some of his contributions include several books, research articles and patents.

Ralph Bruder

Ralph Bruder is current president of Carl von Ossietzky University of Oldenburg. He studied electrical engineering at the Technical University of Darmstadt, where he also received his doctorate in 1992 and worked as a research associate. In 1996, he accepted an appointment at the University of Duisburg-Essen. There, he was a professor of ergonomics in design until 2005 and director of the Institute for Ergonomics and Design Research, which he founded. He was also founding president and, until 2006, executive director of the Zollverein School of Management and Design gGmbH. In 2006, he returned to TU Darmstadt as professor and head of the Institute of Ergonomics. As scientific director, he built up an umbrella organisation for early career researchers. From 2014 to 2019, he was full-time Vice President for Study, Teaching and Graduate Education. He also served as president of the German Society for Occupational Science. In addition to being a member of numerous professional bodies, he is currently chairman of the Academic Advisory Council of the Federal Institute for Occupational Safety and Health. He was also co-editor of the journal Applied Ergonomics and a member of the Academic Advisory Council of several national and international journals.