Testing prototypes with intended end users is critical to the design process. There is limited research on testing prototypes with certain types of end users, specifically children for toy products. Additionally, prototypes evolve in fidelity throughout a project, adding to the complexity in developing best practices for prototype testing. This paper analyzes children's understanding of physical prototypes at various levels of fidelity throughout a university semester-long design project developing wooden toys. Through analyzing students’ feedback on their prototype testing sessions, aspects of the prototypes that aid or inhibit children from understanding both form and function are uncovered. These aspects relate to Norman's principles of interaction and their inclusion in prototypes, specifically mental models, signifiers, and affordances. This paper suggests to include these principles in prototypes early in development to guide the user during testing. The goal of this research is to be a resource for those developing products for children, as well as adding knowledge around prototyping testing at various levels of fidelity.

A Contradiction Matrix of TRIZ that classifies problems to solve as contradictions of features is an effective framework of knowledge management for problem solving. The features, however, may have a problem of completeness because they may not cover contradictions about all physical phenomena. In addition, rigidly structured Contradiction Matrix may have a problem of searchability because a relevant contradiction may not be properly searched if a recorder and a retriever describe it differently. To solve these problems, this paper proposes a semistructured contradiction matrix using not TRIZ features but physical quantities in SI unit. To enable not only exact match but also partial match in searching for relevant contradictions, dimensional similarity and qualitative value similarity of physical quantity and similarity between contradictions are defined. The proposed method is implemented as software in Python and contradictions are described in XML and stored in a semistructured matrix. From the result of similarity calculation between stored contradictions, possible effectiveness of the proposed method is confirmed.

Design is a highly nonlinear chaotic dynamic process with many possible solutions, which requires enormous knowledge for designers. This paper investigates how environment-based design (EBD) methodology can help designers use only necessary knowledge for their creativity based on three methods: information search, knowledge acquisition and knowledge application. The methods are applied in an aircraft pylon design, which is evaluated by two aerospace design specialists. The paper discussed the different roles of EBD for novice and expert designers in regard to overcoming emotion and knowledge barriers to achieving designer creativity.

How can we design and engineer research that leads to the development and effective implementation of complex healthcare interventions? We advocate for a systems design-based approach when initiating clinical research to anticipate the proposition of complex interventions. Using cognitive care as an example, we investigate how hybrid design-inspired methodologies can promote organisational effectiveness and how strong clinical evidence can support successful conceptualisation and uptake of novel interventions into routine clinical practice.

This contribution explores the potential of lead user research for early-stage designing for intelligent ecosystems through a literature review and a single case study concerning a lead user research initiative on blood pressure monitoring. The results suggest advantages of executing lead user research in early-stage designing for intelligent ecosystems from the points of view envisioning broad initial ecosystem boundaries, developing first intelligence components, and overcoming research challenges related to technical issues.

This paper reports the application of the methods and tools of fault-tolerant design to an automated shifting system and their reflection and extension. Fault-tolerant design has emerged in the last years and is generally understood as a collection of strategies, methods, algorithms, tools and insights which are intended to support the development of technical systems which are fault-tolerant because of their controllability but also their inherent fault-tolerant design qualities. The field of application is a shifting system for the gear system of a formula student driverless race car.

Tuned mass dampers may be used to improve vibrational behavior of structures. However, they require space to move. This paper presents an approach to incorporate tuned mass dampers into a lightweight-optimized structure without extra space requirement. It is based on (1) topology optimization (TopOpt) with unit cells and (2) vibration reduction with multiple tuned mass dampers (m-TMD) within the unit cells. The topology optimization is performed with a physics-informed penalty factor, unique to the chosen unit cell. Subsequently, the weight optimal density distribution is realized by populating the design domain with unit cells of ten different densities. To reduce the induced vibration, m-TMDs are placed inside the cavities of the unit cells in the grey scale regions. The effectiveness of the approach is demonstrated for the design of a 2-segment robot arm. The resulting unit cell robotic arm (UC-Arm) is 3.6% lighter than the reference model, maintains the same static performance, and shows a 60% smaller dynamic displacement in the observed frequency range. No extra space is required for the motion of the m-TMD.

A new design methodology for long life and large size (Ll-Ls) products called Design for Installation (DfI) is proposed. Ll-Ls products are usually made up of large parts that need to be assembled on field. The proposed methodology, based on adapted Design Structure Matrix (DSM) and Design for Manufacturing and Assembly (DfMA) methods, enables to optimize the design of a Ll-Ls product in order to reduce time and cost of the installation process. The new methodology works with a conceptual design of the product and the weight and size restrictions given by logistic factors as inputs.

Digital media are a means to deliver products and services, but also a channel to interact with consumers and a source of information on users’ preferences. Data shared by customers on the web, the User-Generated Content (UGC), can give entrepreneurs a detailed perspective of the market. This work examines an application of Natural Language Processing techniques on UGC to discover insights on users' opinions. We collected more than 13.000 reviews of software from digital stores and review website to gather information on the customers’ perspective and their response to a given marketing strategy in two case studies on digital product's launch. The objective is to give support to two Italian companies in the process of business model development through data-driven evidence. We aim to discover who are the users and which are their needs using a lexicon-based approach to mine unstructured text. The results provide qualitative and quantitative descriptions of the market segments. We propose a method to examine UGC and to explore customers’ behavior on social media. The findings helped managers for the development of their business model, enhancing an informed decision-making process.

Global resource consumption is steadily rising. One option for stopping this upward trend is to reduce material consumption in general. With economics built for growth, this is not a practical path to pursue. Another recently explored alternative is the paradigm shift from a linear economy to a circular economy. The most common concept among practitioners and academics comprises the 6R's: Reuse, Repair, Refurbish, Remanufacture, Repurpose, and Recycle. In addition to business cases and supply chains that have been adapted to the circular economy, the products themselves must be circular. Developers face the challenge of developing novel products without appropriate experience from previous tasks.

This paper takes up the challenge of gathering relevant methods in the context of circular product development. A classification with regard to the required input data and use case shall help users effectively and efficiently find development methods suitable for their given development task. With the categorization via a product development framework it is pointed out in which phase existing methods support users and where a lack of support occurs.

This paper introduces a new concept for the automation of the assembly planning process, to enable Design for Assembly (DfA). The approach involves the application of reinforcement learning (RL) to assembly sequence planning (ASP) based on a 3D-CAD model. The ASP algorithm determines assembly sequences through assembly by disassembly. The assembly sequence is then used for the generation of subassemblies by considering the product contact information. The approach aims to support the creation of the manufacturing bill of materials (MBOM) by automating the assembly planning process.

The development of product-service systems (PSS) requires the design of value propositions, which involves challenging activities. In the context of business model innovation, gamification is presented as a practical mechanism to support the design process. This study aims to create a prototype of a gamified approach to design PSS value propositions and to compare its application to a traditional design approach. Based on a design experiment, the advantages and problems for both approaches were evaluated, providing insights for further development of the new version of the gamified approach.

Increasing complexity of products and design processes leads to intensive collaboration of different stakeholders in technical product development. This causes a demand for suitable methods of collaboration across department interfaces, as between design and simulation. The paper investigates typical barriers of collaboration at this interface and measures to overcome them. Methods of complexity management form links based on literature and empirical data from online surveys and interview studies. The framework uses a set of structural metrics to analyse collaboration networks systematically.

This paper presents five industrial cases where design automation (DA) systems supported by design optimization has been developed, and aims to summarize the lesson learned and identify needs for future development of such projects. By mapping the challenges during development and deployment of the systems, common issues were found in technical areas such as model integration and organizational areas such as knowledge transfer. The latter can be seen as a two-layered design paradox; one for the product that the DA system is developed for, and one for the development of the DA system.

This paper is an invitation to a debate on the positioning of engineering design as a field of research. The paper lists a multiplicity of interpretations of design, questioning whether they are sufficient to describe engineering design in all its variety. Following a critical analysis of attempts to describe design's unique characteristics, and observations on the nature of design made from outside of the design research community, it presents a list of situations of design that the authors have observed in engineering practice, describing especially the relationship between design, technology and society. The paper then explores what these situations imply about the questions researchers should ask about the nature of design knowledge and expertise, and examines how the different situations might be categorised, before exploring the positioning of engineering design research with respect to other academic disciplines, in particular management and the human and earth sciences. The paper concludes with a call to a debate on the nature of engineering design with the aim to define this field more clearly to ourselves and to others.

Engineering designers seek to explore ‘real’ problems that must be solved across design processes. This exploration might be challenging in complex problem situations. An effective way of encouraging design exploration is conjecture-based problem exploration—informing problem re-interpretation by potential solutions. However, little evidence indicated how this process unfolds, especially in complex problem situations. This study addresses this question by articulating the underlying cognitive mechanism of conjecture-based problem exploration. Situated in a creative design practice that tackles real-world, complex problem situations, we employ grounded theory to conduct qualitative coding of interview transcripts and documents elicited from ten multidisciplinary graduate students. We developed a three-phase process model to explain conjecture-based problem exploration: (1) triggering through analogizing, inspiring, evaluating, and questioning; (2) transitioning to problem space expansion; and (3) resulting in problem focus adjustment incrementally or radically. Our explanation contributes to design theory building and encourages engineering designers to embrace a dynamic view of design problems when addressing complexity.

The emergence of intermediary platforms created networks that facilitate peer-to-peer interactions, as well as encourage the sharing of goods and services within the context of collaborative consumption and cost saving. This article sets out to inspect “why the sharing economy is so successful” and provide a critical viewpoint on the topic's essential ideas, while also taking a perspective on the advantages and disadvantages that affect the end users. A literature review paired with case studies of Airbnb, Uber, and other applications of the shared economy, looks upon how despite their rapid market growth in the past decade and public approval, such platforms caused disruptions to the markets they operate in. Results indicate that by being involved as a part of the collaborative consumption ecosystem, either as a provider or a user, the absence of personal ownership is key, while the utilisation of the product needs to be maximised to result in a pleasant experience. However, it is critical that the development of these platforms which thrive on connecting people stays closely monitored by regulatory bodies, and that the legislation needed for prevention of unethical practices follows quickly enough to ensure rightful operation.

A data analysis method aiming to support cause and effect analysis in design exploration studies is presented. The method clusters and aggregates effects of multiple design variables based on the structural hierarchy of the evaluated system. The resulting dataset is intended as input to a visualization construct based on colour-coding CAD models. The proposed method is exemplified in a case study showing that the predictive capability of the created, clustered, dataset is comparable to the original, unmodified, one.

Electric vehicles are playing an increasingly important role in the agricultural sector. The selection of tyres for reducing energy loss due to rolling resistance is an important consideration in determining the viability of these vehicles. To date little is known about rolling resistance of small all-terrain vehicles. In this study a test rig was used to collect rolling resistance data for seven ATV tyres. The study verifies the relationship between normal load and rolling resistance and gives insight into some of the important considerations when selecting tyres for small off road vehicles.

Hierarchies of knowledge represent a popular formalism for conceptualizing beliefs, justifications, and truth statements. To capitalize on the opportunity for formulating effective maps of design knowledge, this article introduces the hierarchical context–design development–high-level (CDH) model that stratifies different bodies of design-specific knowledge into ranked levels. We compare it with existing hierarchical models of knowledge, and describe its unique uses and benefits for both design research and design practice.