Abstract: Postpartum haemorrhage (PPH) is an obstetric emergency causing nearly one-quarter of maternal deaths worldwide, 99% of these in low-resource settings (LRSs). Uterine balloon tamponade (UBT) devices are a non-surgical treatment to stop PPH. In LRSs, low-cost versions of UBT devices are based on the condom balloon tamponade (CBT) technique, but their effectiveness is limited. This paper discusses the experimental study to assess the usability and performance of a medical device, BAMBI, designed as an alternative to current CBT devices. The testing phase involved medical and non-medical personnel and was focused on testing BAMBI's usability and effectiveness compared to a standard CBT solution. We collected measures of the execution time and the procedure outcome. Different training procedures were also compared. Results show a significant preference for the BAMBI device. Besides, medical and non-medical subjects reached comparable outcomes. This aspect is highly relevant in LRSs where the availability of medical personnel could be limited

Keywords: Maternal mortality | Medical device | Patient safety | Sustainable development goals | Usability | User-centered design | Uterine balloon tamponade device

Abstract: This study investigates the synergy between additive manufacturing (AM) technologies and computational design strategies in jewellery and how that synergy can be successfully exploited to extend innovation in that field further. A case study called Ecdysis, a bioinspired jewellery collection, is presented. A dedicated computational algorithm has been developed and is described in detail. This algorithm allows for the exploitation of the shape and functional complexity dimensions allowed by AM and the control of the printability of the generated concept. Shape and functional complexity are exploited to mimic the beauty and dynamism of snakes’ slithering mechanism. At the same time, starting from the developed algorithm, multiple digital models and physical prototypes have been fabricated, leveraging material extrusion, vat photopolymerisation, and powder bed fusion processes. This further development step of the collection thus confirms the versatility of both the proposed approach and AM technologies for jewellery. Therefore, the paper demonstrates how unique wearing experiences can be created and how uniqueness can be simultaneously preserved and democratised in jewellery by deepening the synergy between AM technologies and computational strategies.

Keywords: Bioinspired design | Computational design | Design for additive manufacturing | Interaction design | Jewellery

Abstract: Purpose: This study evaluates the potential of using the material extrusion (MEX) process for recycling waste tire rubber (WTR). By investigating the process parameters, mechanical behaviour and morphological characterisation of a thermoplastic polyurethane-waste tire rubber composite filament (TPU-WTR), this study aims to establish a framework for end-of-life tire (ELT) recycling using the MEX technology. Design/methodology/approach: The research assesses the impact of various process parameters on the mechanical properties of the TPU-WTR filament. Hysteresis analysis and Poisson’s ratio estimation are conducted to investigate the material’s behaviour. In addition, the compressive performance of diverse TPU-WTR triply periodic minimal surface lattices is explored to test the filament suitability for printing intricate structures. Findings: Results demonstrate the potential of the TPU-WTR filament in developing sustainable structures. The MEX process can, therefore, contribute to the recycling of WTR. Mechanical testing has provided insights into the influence of process parameters on the material behaviour, while investigating various lattice structures has challenged the material’s capabilities in printing complex topologies. Social implications: This research holds significant social implications addressing the growing environmental sustainability and waste management concerns. Developing 3D-printed sustainable structures using recycled materials reduces resource consumption and promotes responsible production practices for a more environmentally conscious society. Originality/value: This study contributes to the field by showcasing the use of MEX technology for ELT recycling, particularly focusing on the TPU-WTR filament, presenting a novel approach to sustainable consumption and production aligned with the United Nations Sustainable Development Goal 12.

Keywords: Additive manufacturing | Circular economy | Design for additive manufacturing | Recycling | Sustainability | Sustainable Development Goals | Triply periodic minimal surface | Waste tire rubber

Abstract: The 3.1 target of the Sustainable Development Goals of the United Nations aims to reduce the global maternal mortality ratio to less than 70 maternal deaths per 100,000 live births by 2030. The last updates on this target show a significant stagnation in the data, thus reducing the chance of meeting it. What makes this negative result even more serious is that these maternal deaths could be avoided through prevention and the wider use of pharmacological strategies and devices to stop postpartum haemorrhage (PPH). PPH is the leading obstetric cause of maternal mortality in low- and middle-income countries (LMICs). Despite low-cost devices based on the uterine balloon tamponade (UBT) technique are already available, they are not safe enough to guarantee the complete stop of the bleeding. When effective, they are too expensive, especially for LMICs. To address this issue, this study presents the design, mechanical characterisation and technology assessment performed to validate a novel low-cost UBT kit, particularly a novel component, i.e., the connector, which guarantees the kit’s effectiveness and represents the main novelty. Results proved the device’s effectiveness in stopping PPH in a simulated scenario. Moreover, economic and manufacturing evaluations demonstrated its potential to be adopted in LMICs.

Abstract: Additive Manufacturing provides unprecedented opportunities for designing and producing intricate, architected materials with exceptional properties while maintaining reduced weight. One of the most straightforward ways to create such structures is to mimic the lattice geometries of crystals. New approaches are now exploring how to influence the behaviour of these structures by mimicking not only the crystal arrangement but also peculiar mechanisms occurring at the crystallographic scale. In such a context, this study first presents a hexagonal close-packed (HCP) lattice derived from the homonymous crystal structures of Ti or Zr metals. Subsequently, the twinning phenomenon responsible for the plastic deformation of these metals is reproduced geometrically into this structure to improve its energy absorption capability. Compressive tests conducted on 3D-printed samples confirm such a hypothesis: the specific energy absorption of twinned structures is significantly higher than that of the equivalent HCP ones, with an increase of up to 24.3%. Introducing twinned regions stabilises the plastic deformation despite a limited reduction of the peak stress. Therefore, replicating the twinning metallurgical mechanism within an HCP-inspired metamaterial proves successful, further validating the approach of mimicking and transferring atomic phenomena at a different scale to tailor the properties of architected materials.

Keywords: Additive manufacturing | Architected materials | Crystal twinning | Hexagonal close-packed | Metamaterials

Abstract: Auxetics are a class of materials and metamaterials with a negative Poisson’s ratio (ν) and have gained tremendous popularity over the last three decades. Many studies have focused on characterizing designs that allow obtaining a negative ν. However, some open issues remain concerning understanding the auxetic behavior in operational conditions. Studies have been centered on analyzing the response of specific auxetic topologies instead of treating auxeticity as a property to be analyzed in a well-defined structural context. This study aims to contribute to the investigation of auxetic materials with a structural application, focusing on maximizing performance. The field of application of auxetics for designing inserts was selected and a model of a nail-cavity system was created to determine the effects of different design choices on the system behavior by exploring relationships between selected parameters and the auxetic insert behavior. The exploration combines finite element modeling analyses with their surrogate models generated by supervised learning algorithms. This approach allows for exploring the system’s behavior in detail, thus demonstrating the potential effectiveness of auxetics when used for such applications. A list of design guidelines is elaborated to support the exploitation of auxetics in nail-cavity systems.

Keywords: auxetic structures | finite element method | insert | nail | regression models

Abstract: Radical technological innovations are emerging in response to environmental, economic and geopolitical pressures. This affects how we design and manufacture new solutions. Additive manufacturing, one of the enabling technologies of the digital transition, can support more-sustainable manufacturing processes if developed through a system-level approach. In this Perspective, we adopt such an approach: we propose to use established sustainable design methods to innovate additive manufacturing systems and to consider how to make additive manufacturing an enabler of sustainable design in combination with conventional manufacturing. We then discuss how to implement our vision to enable additive manufacturing for sustainability

Abstract: Purpose: This study aims to deepen the knowledge concerning the metal fused filament fabrication technology through an analysis of the printing parameters of a commercial 316L stainless steel filament and their influence on the porosity and mechanical properties of the printed parts. It also investigates the feasibility of manufacturing complex geometries, including strut-and-node and triply periodic minimal surface lattices. Design/methodology/approach: A three-step experimental campaign was carried out. Firstly, the printing parameters were evaluated by analysing the green parts: porosity and density measurements were used to define the best printing profile. Then, the microstructure and porosity of the sintered parts were investigated using light optical and scanning electron microscopy, while their mechanical properties were obtained through tensile tests. Finally, manufacturability limits were explored with reference samples and cellular structures having different topologies. Findings: The choice of printing parameters drastically influences the porosity of green parts. A printing profile which enables reaching a relative density above 99% has been identified. However, voids characterise the sintered components in parallel planes at the interfaces between layers, which inevitably affect their mechanical properties. Lattice structures and complex geometries can be effectively printed, debinded, and sintered if properly dimensioned to fulfil printing constraints. Originality/value: This study provides an extensive analysis of the printing parameters for the 316L filament used and an in-depth investigation of the potential of the metal fused filament fabrication technology in printing lightweight structures.

Keywords: 316L stainless steel | Design for additive manufacturing | Lattice structures | Metal fused filament fabrication | Printing parameters | Triply periodic minimal surface

Abstract: Despite its significant advantages in terms of design freedom and the wide range of processable materials, the Binder Jetting technology has not yet received substantial attention in the healthcare field, especially concerning the fabrication of metal components. Hence, the paper investigates how this technology could be exploited to innovate the medical instrument field. Based on selected case studies, some preliminary design indications are derived on how to properly consider the various phases (i.e., printing, depowdering, and sintering) and related challenges of the Binder Jetting process.

Keywords: additive manufacturing | binder jetting | biomedical design | design for additive manufacturing

Abstract: The design of biomimetic porous scaffolds has been gaining attention in the biomedical sector lately. Shells, marine sponges, shark teeth, cancellous bone, sea urchin spine, and the armadillo armor structure are examples of biological systems that have already been studied to drive the design of innovative, porous, and multifunctional structures. Among these, triply periodic minimal surfaces (TPMSs) have attracted the attention of scientists for the fabrication of biomimetic porous scaffolds. The interest stems from their outstanding properties, which include mathematical controllable geometry features, highly interconnected porous architectures, high surface area to volume ratio, less stress concentration, tunable mechanical properties, and increased permeability. All these distinguishing features enable better cell adhesion, optimal integration to the surrounding tissue avoiding stress shieldings, a good permeability of fluid media and oxygen, and the possibility of vascularization. However, the sophisticated geometry of these TPMS-based structures has proven challenging to fabricate by conventional methods. The emergence of additive manufacturing (AM) and the enhanced manufacturing freedoms and flexibility it guarantees could solve some of the bottlenecks, thus leading to a surge of interest in designing and fabricating such structures in this field. Also, the feasibility of using AM technologies allows for obtaining size programmable TPMS printable in various materials, from polymers to metal alloys. Here, a comprehensive overview of 3D-printed TPMS porous structures is provided from a design for additive manufacturing (DfAM) and application perspective. First, design strategies, geometry design algorithms, and related topological optimization are introduced according to diverse requirements. Based on that, the performance control of TPMS and the pros and cons of the different AM processes for fabricating TPMS scaffolds are summarized. Lastly, practical applications of 3D-printed biomimetic TPMS porous structures for the biomedical field are presented to clarify the advantages and potential of such structures.

Keywords: Additive manufacturing | Biomimetic | Design for additive manufacturing | Metamaterials | Porous structures | Triply periodic minimal surfaces

Abstract: The percolation of organic Phase Change Materials (PCMs) into metallic skeletons produces Composite PCMs (C-PCMs). This paper explores Al-Si-Mg alloy Sheet-based Primitive-Schwarz (PS) Triply Periodic Minimal Surface (TPMS) C-PCMs filled by paraffines, comparing them with C-PCMs built with inverse Body-Centred Cubic (BCC) structures. The aim is to derive guidelines for improving the thermal response flexibility of these systems. The lattice geometrical features and C-PCM properties are calculated and modelled as a function of porosity (ε), proportional to storable energy. For ε > 0.8, the Effective Thermal Conductivity (λeff) of PS-based C-PCMs is higher than that of BCC-based, reaching 68 % of the maximum theoretical value. Design considerations are used to define a set of feasible C-PCMs whose thermal response is numerically simulated. The PS favours shorter transients than BCC (6.3 % less for ε =0.8). The ε increase, and, consequently, λeff reduction, in PS-based C-PCMs raises both storage potential and storage times (542 s vs 694 s for ε = 0.8 vs 0.9). Minor changes in the storage times can be obtained by lattice size variation at constant ε. The peculiarity of sheet-based TPMSs of splitting the volume into non-interconnected subdomains is exploited to design 3-phase C-PCMs, employing two PCMs having different melting temperatures.

Keywords: Additive manufacturing | Composite phase change materials (PCM) | Energy storage | Triply periodic minimal surface

Abstract: Lattice structures with triply periodic minimal surfaces (TPMS) built using flexible materials are soft porous solids applicable in various fields, including biomedicine and tissue engineering. Such structures are also relevant for material extrusion additive manufacturing (MEAM), whose wide diffusion is pivotal to fostering their spread. Although design approaches are available to exploit the potential of soft TPMS, there are still manufacturing constraints that lead to practical limits on the shape and size of the structures that can be produced due to the complexities related to printing flexible materials. Besides, the computational models investigating the effect of cell type, the surface-to-volume fraction, and the combination of different periodic surfaces (i.e., graded or hybrid) on the mechanical behavior of these lattices are design aspects still debated. Here, the capabilities of MEAM to produce tailored soft lattice structures are explored by combining a design tool, numerical analyses, and mechanical testing using thermoplastic polyurethane (TPU) as feedstock material. The study addresses design issues, delves into optimum printing parameters, and analyzes a set of numerical parameters, which can be used for designing specific structures with tunable mechanical behavior, useful for healthcare and bioengineering. The printing parameters of three lattices, i.e., schwartz-P, gyroid, and honeycomb, with unit cell sizes spanning from 3 to 12 mm were studied. Their mechanical behavior was investigated using FEM simulations and mechanical testing. Lastly, the printability of graded and hybrid lattices with enhanced bearing-load capabilities have been demonstrated. Altogether, our findings addressed multiple challenges associated with developing soft lattice scaffolds with MEAM that can be used to fabricate innovative-engineered materials with tunable properties.

Keywords: Design for additive manufacturing | Finite element analysis (FEM) | Fused filament fabrication (FFF) | Lattice structures | Thermoplastic polyurethane (TPU) | Triply periodic minimal surfaces (TPMS)

Abstract: Each year 65% of young athletes and 25% of physically active adults suffer from at least one musculoskeletal injury that prevents them from continuing with physical activity, negatively influencing their physical and mental well-being. The treatment of musculoskeletal injuries with the adhesive elastic kinesiology tape (KT) decreases the recovery time. Patients can thus recommence physical exercise earlier. Here, a novel KT based on auxetic structures is proposed to simplify the application procedure and allow personalization. This novel KT exploits the form-fitting property of auxetics as well as their ability to simultaneously expand in two perpendicular directions when stretched. The auxetic contribution is tuned by optimizing the structure design using analytical equations and experimental measurements. A reentrant honeycomb topology is selected to demonstrate the validity of the proposed approach. Prototypes of auxetic KT to treat general elbow pains and muscle tenseness in the forearm are developed.

Abstract: Purpose: This study aims to investigate the behaviour of soft lattices, i.e. lattices capable of reaching large deformations, and the influence of the printing process on it. The authors focused on two cell topologies, the body-centred cubic (BCC) and the Kelvin, characterized by a bending-dominated behaviour relevant to the design of energy-absorbing applications. Design/methodology/approach: The authors analysed the experimental and numerical behaviour of multiple BCC and Kelvin structures. The authors designed homogenous and graded arrays of different dimensions. The authors compared their technical feasibility with two three-dimensional-printed technologies, such as the fused filament fabrication and the selective laser sintering, choosing thermoplastic polyurethane as the base material. Findings: The results demonstrate that multiple design aspects determine how the printing process influences the behaviour of soft lattices. Besides, a graded distribution of the material could contribute to fine-tuning this behaviour and mitigating the influence of the printing process. Practical implications: Despite being less explored than their rigid counterpart, soft lattices are now becoming of great interest, especially when lightweight, wearable and customizable solutions are needed. This study contributes to filling this gap. Originality/value: Only a few studies analyse design and printing issues of soft lattices due to the intrinsic complexity of printing flexible materials.

Keywords: Cellular structures | Fused filament fabrication | Selective laser sintering | Soft lattices | Thermoplastic polyurethane

Abstract: The escalating demand for torsion- and bending-resistant structures paired with the need for more efficient use of materials and geometries, have led to novel bio-inspired ingenious solutions. However, lessons from Nature could be as inspiring as they are puzzling: plants and animals offer an enormous range of promising but hierarchically complex configurations. Avian bones are prominent candidates for addressing the torsional and bending issue. They present a unique intertwining of simple components: helicoidal ridges and crisscrossing struts, able to bear flexural and twisting actions of winds. Here, it is set how to harmonically move from the natural to the engineering level to formalize and analyze the biological phenomena under controlled design conditions. The effect of ridges and struts is isolated and combined toward tailored torsion and bending-resistant arrangements. Then the biological level is revisited to extrapolate the avian allometric design approach and is translated into multiscale lightweight structures at the engineering level. This study exploits the complexity of Nature and the scalability that characterizes the evolutionary design of bird bones through the design and fabrication versatility allowed by additive manufacturing technologies. This paves the way for exploring the transferability of the proposed solution at multiple engineering scales.

Keywords: 3D printing | avian-inspired structures | bending resistance | scalability | torsion resistance

Abstract: Purpose: The purpose of this study is to describe the design and validation of a three-dimensional (3D)-printed phantom of a uterus to support the development of uterine balloon tamponade devices conceived to stop post-partum haemorrhages (PPHs). Design/methodology/approach: The phantom 3D model is generated by analysing the main requirements for validating uterine balloon tamponade devices. A modular approach is implemented to guarantee that the phantom allows testing these devices under multiple working conditions. Once finalised the design, the phantom effectiveness is validated experimentally. Findings: The modular phantom allows performing the required measurements for testing the performance of devices designed to stop PPH. Social implications: PPH is the leading obstetric cause of maternal death worldwide, mainly in low- and middle-income countries. The proposed phantom could speed up and optimise the design and validation of devices for PPH treatment, reducing the maternal mortality ratio. Originality/value: To the best of the authors’ knowledge, the 3D-printed phantom represents the first example of a modular, flexible and transparent uterus model. It can be used to validate and perform usability tests of medical devices.

Keywords: 3D printing | Design for additive manufacturing | Device validation | Phantom | Post-partum haemorrhage

Abstract: This paper analyses the design and measurement issues that deal with the development of uterine balloon tamponade devices to treat post-partum haemorrhage to be used in low-resource settings. This emergency situation requires low-cost, reliable, and easy-to-use solutions to stop the bleeding quickly. The analysis highlights that, although solutions are already available, still, there are issues concerning the quantification of blood lost volume, the measure of the pressure applied by the tamponade system to the uterine walls, and the lack of a user-centred design approach focused on the woman.

Keywords: Maternal mortality | Post-partum haemorrhage | User-centred design

Abstract: Starting from the pro-environmental potential of virtual reality (VR), the aim was to understand how different statistical information formats can enhance VR persuasive potential for plastic consumption, recycling and waste. Naturalistic, immersive virtual reality environments (VREs) were designed ad hoc to display three kinds of statistical evidence formats, featured as three different formats (i.e., numerical, concrete and mixed). Participants were exposed only to one of the three formats in VR, and their affect, emotions, sense of presence, general attitudes toward the environment, specific attitudes and behavioral intentions toward plastic, use, waste, recycle, as well as their social desirability proneness were measured. Numerical format was the least effective across all dimensions. Concrete and mixed formats were similar. Social desirability only partially affected participants’ attitudes and behavioral intentions. Numerical format did not increase the persuasive efficacy of statistical evidence displayed in VR, with respect to visual alone. Implications and future directions for designing effective VRE promoting pro-environmental behaviors were discussed.

Keywords: Concrete | Format | Numerical | Plastic | Statistical evidence | Virtual reality

Abstract: The current and future challenges of sustainable development require a massive transformation of habits and behaviors in the whole society at many levels. This demands a change of perspectives, priorities, and practices that can only result from the development of more aware, informed, and instructed communities and individuals. The field of design for sustainable behavior is answering this need through the development of products, systems, and services to support the change of people’s habits and decision-making processes. In this regard, Virtual Reality (VR) is a promising tool: it has already been explored to drive sustainable behavior change in several situations, through a wide range of devices, technologies, and modalities. This variety provides uncountable opportunities to designers, but it comes with a series of ethical, psychological, and technical questions. Hence, VR developers should be able to distinguish and identify possible strategies, delivering suitable solutions for each case study. In this work, we present a framework for the development of VR experiences to support sustainable behavior change, based on a systematic review. We consider the various features to manage and possible alternatives when creating a VR experience, linking them to the behavioral aspects that can be addressed according to the project’s aim. The framework will provide designers with a tool to explore and orient themselves towards possible sets of optimal choices generating tailored solutions.

Keywords: Design framework | Sustainable behavior | Virtual reality

Abstract: Nature has always been a source of inspiration for designers and engineers, through the imitation of biological patterns and structures. This emulating and creative process is nowadays supported by technologies and tools as additive manufacturing and computational design. This paper describes the design and prototyping of a lamp inspired by a plant called Physalis Alkekengi, known as Chinese Lantern. We present the development of an algorithm, based on a computational model from literature, to realize the 2D pattern and leaves. They were then 3D printed to create the structure of the lamp and obtain an aesthetical and symbolic shading effect.

Keywords: Bio-inspired design / biomimetics | Computational design methods | Design for Additive Manufacturing (DfAM)

Abstract: Learning from Nature and leveraging 3D printing, mechanical testing, and numerical modeling, this study aims to provide a deeper understanding of the structure-property relationship of crystal-lattice-inspired materials, starting from the study of single unit cells inspired by the cubic Bravais crystal lattices. In particular, here we study the simple cubic (SC), body-centered cubic (BCC), and face-centered cubic (FCC) lattices. Mechanical testing of 3D-printed structures is used to investigate the influence of different printing parameters. Numerical models, validated based on experimental testing carried out on single unit cells and embedding manufacturing-induced defects, are used to derive the scaling laws for each studied topology, thus providing guidelines for materials selection and design, and the basis for future homogenization and optimization studies. We observe no clear effect of the layer thickness on the mechanical properties of both bulk material and lattice structures. Instead, the printing direction effect, negligible in solid samples, becomes relevant in lattice structures, yielding different stiffnesses of struts and nodes. This phenomenon is accounted for in the proposed simulation framework. The numerical models of large arrays, used to define the scaling laws, suggest that the chosen topologies have a mainly stretching-dominated behavior- A hallmark of structurally efficient structures-where the modulus scales linearly with the relative density. By looking ahead, mimicking the characteristic microscale structure of crystalline materials will allow replicating the typical behavior of crystals at a larger scale, combining the hardening traits of metallurgy with the characteristic behavior of polymers and the advantage of lightweight architected structures, leading to novel materials with multiple functions.

Keywords: 3D printing | bioinspired materials | lattice structure | lightweight structure | trabecular structure

Abstract: Purpose: This paper aims to investigate the feasibility of supportless printing of lattice structures by metal fused filament fabrication (MF3) of Ti-6Al-4V. Additionally, an empirical method was presented for the estimation of extrudate deflection in unsupported regions of lattice cells for different geometric configurations. Design/methodology/approach: Metal-polymer feedstock with a solids-loading of 59 Vol.% compounded and extruded into a filament was used for three-dimensional printing of lattice structures. A unit cell was used as a starting point, which was then extended to multi-stacked lattice structures. Feasible MF3 processing conditions were identified to fabricate defect-free lattice structures. The effects of lattice geometry parameters on part deflection and relative density were investigated at the unit cell level. Computational simulations were used to predict the part quality and results were verified by experimental printing. Finally, using the identified processing and geometry parameters, multi-stacked lattice structures were successfully printed and sintered. Findings: Lattice geometry required considerable changes in MF3 printing parameters as compared to printing bulk parts. Lattice cell dimensions showed a considerable effect on dimensional variations and relative density due to varying aspect ratios. The experimental printing of lattice showed large deflection/sagging in unsupported regions due to gravity, whereas simulation was unable to estimate such deflection. Hence, an analytical model was presented to estimate extrudate deflections and verified with experimental results. Lack of diffusion between beads was observed in the bottom facing surface of unsupported geometry of sintered unit cells as an effect of extrudate sagging in the green part stage. This study proves that MF3 can fabricate fully dense Ti-6Al-4V lattice structures that appear to be a promising candidate for applications where mechanical performance, light-weighting and design customization are required. Originality/value: Supportless printing of lattice structures having tiny cross-sectional areas and unsupported geometries is highly challenging for an extrusion-based additive manufacturing (AM) process. This study investigated the AM of Ti-6Al-4V supportless lattice structures using the MF3 process for the first time.

Keywords: Additive manufacturing | Deflection prediction | Finite element analysis simulation | Lattice structure | Metal fused filament fabrication | Titanium Ti-6Al-4V

Abstract: This paper describes an innovative 3D-printed beam-based lightweight structure that is used to increase the adhesion strength of metal-composite joints without damaging the composite fibers. It is conceived as the interface between the two parts to be joined: by filling the voids of this structure with resin, a mechanical interlocking effect can be generated to enhance the mechanical properties of the junction. A dedicated design workflow was defined to explore different types of 3D beam-based structures, starting from the analysis of the main failure modes of this type of junction. Tensile tests were performed on both polymeric and metal samples to validate the effectiveness of this interlocking strategy. Results demonstrated an increase in the adhesion strength relative to standard adhesive joints. A possible practical implementation is also discussed: a new type of insert is presented for application in metal-to-polymer composite joints. Finally, such a beam-based joining approach also represents an innovative application in the field of design for additive manufacturing.

Keywords: 00-01 | 99-00 | Design for additive manufacturing | Lattice structures | Material extrusion | Metal-composite junctions | Powder bed fusion

Abstract: The recent interest in human-robot interaction requires the development of new gripping solutions, compared to those already available and widely used. One of the most advanced solutions in nature is that of the human hand, and several research contributions try to replicate its functionality. Technological advances in manufacturing technologies and design tools are opening possibilities in the design of new solutions. The paper reports the results of the design of an underactuated artificial robotic hand, designed by exploiting the benefits offered by additive manufacturing technologies.

Keywords: 3D printing | additive manufacturing | design for additive manufacturing | mechatronics

Abstract: In Mass Customisation (MC), products are intrinsically variable, because they aim at satisfying end-users’ requests. Modular design and flexible manufacturing technologies are useful strategies to guarantee a wide product variability. However, in the eyewear field, the current strategies are not easily implementable, due to some eyewear peculiarities (e.g., the large variability of the frame geometry and material, and the necessity to use specific manufacturing phases). For example, acetate spectacle-frames are bent through a thermoforming process. This particular phase requires dedicated moulds, whose geometry strictly depends on the frame model to be bent; consequently, changes of the frame geometry continuously require new moulds, which have to be designed, manufactured, used, and finally stored. The purpose of this paper is to propose a new strategy to transform a dedicated tool (i.e., a thermoforming mould) into a reconfigurable one, to optimise the tool design, manufacturing and use. First, how the frame features influence the mould geometry has been investigated, creating a map of relations. On the basis of this map, the conventional monolithic-metallic mould was divided into “standard” (re-usable) and “special” (ad-hoc) modules, where the “special” ones are in charge of managing the variability of the product geometry. The mapped relations were formalised as mathematical equations and then, implemented into a Knowledge Based Engineering (KBE) system, to automatically design the “special” modules and guarantee the mould assemblability. This paper provides an original example of how a reconfigurable thermoforming mould can be conceived and how a KBE system can be used to this aim.

Keywords: Eyewear | KBE system | Mass customisation | Thermoforming mould

Abstract: The potentiality of the Fused Deposition Modeling (FDM) process for multi-material printing has not yet been thoroughly explored in the literature. That is a limitation considering the wide diffusion of dual extruders printers and the possibility of increasing the number of these extruders. An exploratory study, based on tensile tests and performed on double-material butt-joined bars, was thus conceived; the aim was to explore how the adhesion strength between 3 pairs of filaments (TPU-PLA, PLA-CPE, CPE-TPU) is influenced by the material printing order, the type of slicing pattern used for the layers at the interface, and the infill density of the layers below the interface. Results confirm the effectiveness of mechanical interlocking strategies in increasing the adhesion strength even when thermodynamic and diffusion mechanisms of adhesion are not robust enough. Besides, thermal aspects also demonstrated to play a relevant role in influencing the performance of the interface.

Keywords: design for additive manufacturing | fused deposition modelling (FDM) | multi-material adhesion | Multi-material printing | slicing parameters

Abstract: The paper describes the design of a wearable and wireless system that allows the real-time identification of some gestures performed by basketball players. This system is specifically designed as a support for coaches to track the activity of two or more players simultaneously. Each wearable device is composed of two separate units, positioned on the wrists of the user, connected to a personal computer (PC) via Bluetooth. Each unit comprises a triaxial accelerometer and gyroscope, a microcontroller, installed on a TinyDuino platform, and a battery. The concept of activity recognition chain is investigated and used as a reference for the gesture recognition process. A sliding window allows the system to extract relevant features from the incoming data streams: mean values, standard deviations, maximum values, minimum values, energy, and correlations between homologous axes are calculated to identify and differentiate the performed actions. Machine learning algorithms are implemented to handle the recognition phase.

Abstract: Purpose: The purpose of this paper is to describe an innovative Parametric and Adaptive Slicing (PAS) technique to be used for generating material addition paths along three-dimensional surfaces. Design/methodology/approach: The method is grounded on the possibility to generate layers starting from multiple reference surfaces (already available in the model or created on purpose). These are used for mathematically deriving a family of parametric surfaces whose shape and spacing (the layer thickness) can be tuned to get the desired aesthetic, technical and functional characteristics. The adhesion among layers is obtained guaranteeing a smooth transition among these surfaces. Findings: The examples described in the paper demonstrate that the PAS technique enables the addition of the material along non-planar paths and, hence, the elimination of the staircase effect. In addition, objects printed using this technique show improved mechanical properties with respect to those printed using standard planar layers. Research limitations/implications: As the method allows a local control of the material addition/deposition, it can be used to design the mechanical behavior of the objects to be printed. Originality/value: The technique proposed in this paper overcomes the limitations of currently available adaptive and curved layer slicing strategies, by introducing the possibility to generate layers with a non-constant thickness whose shape morphs smoothly from one layer to another.

Keywords: Additive manufacturing | Computer aided design | Computer aided manufacturing | Curved layer | Design for additive manufacturing | Geometrical modelling

Abstract: The scarce availability of water in highly populated cities is about to become a social problem. While the water service companies work on improving the distribution network in order to reduce losses, it is evident that one of the main problems is due to an excess of use of this resource by users. This consumption is relatively controlled when excessive consumption is clearly associated, in the consumer mind, with high costs. However, when users are in public places they tend to consume water because of a loss of correlation with costs. In this paper, we describe the design of a device to be installed in public environments, which aims to reduce the consumption of water. The device measures in real time the flow of water and sends the user visual and sound information trying to create a link between consumption and costs. The device has been installed in a university campus bathroom and has been tested. Test results show a reduction in water consumption, especially in the interactive prototype approach compared to the conventional treatment. Further modifications for future development of the interactive device is also discussed.

Keywords: Design for sustainable behavior | Multisensory product experience | Sustainability | User centred design | Water conservation

Abstract: 3D printed heterogeneous lattice structures are beam-and-node based structures characterised by a variable geometry. This variability is obtained starting from a periodic structure and modifying the relative density of the unit cells or by combining unit cells having different shapes. While several consolidated design approaches are described to implement the first approach, there are still computational issues to be addressed to combine different cells properly. In this paper, we describe a preliminary experimental study focused on exploring the design issues to be addressed as well as the advantages that this second type of heterogeneous structures could provide. The Three-Point-Bending test was used to compare the behaviour of different types of heterogeneous structures printed using the Fused Deposition Modeling (FDM) technology. Results demonstrated that the possibility of combining multiple unit cells represents a valid strategy for performing a more effective tuning of the material distribution within the design space. However, further studies are necessary to explore the behaviour of these structures and develop guidelines for helping designers in exploiting their potential.

Keywords: 3D printing | Design for Additive Manufacturing (DfAM) | Heterogeneous lattice structures | Lightweight design

Abstract: Although it is noted that interpersonal sensorimotor coordination can influence several high-level socio-cognitive processes, its impact on creative collaboration is nearly unexplored. Here, we investigated the effects of a form of sensorimotor coordination, that is, sensorimotor synchronization, on a subsequent creative collaboration task. 60 pairs (n total = 120 participants) formed by previously unacquainted individuals performed a tower-building task either jointly or alone, followed by a dyadic creativity task. Tower building time in the joint condition was recorded through a sensorized platform and creativity performance was evaluated by two independent raters based on the quantity and quality of generated ideas. We controlled for gender composition and for the disposition to cooperate and to adopt a creative, analytical style. Results showed that male-male couples were more creative after the joint-action condition, whereas female-female and mixed-gender couples were more creative after the solo condition. Regression analyses of tower building time on creativity performance revealed that building time was a significant predictor of creativity dimensions in male-male and in mixed-gender couples but did not predict creative performance in female-female couples. Overall, these findings suggest that the manipulation of sensorimotor coordination can influence performance in a subsequent creative collaboration task, with the nature, and magnitude of this effect depending on the gender composition of the dyads. These results have potential implications for the design of sensorimotor-based strategies to enhance dyadic creative performance in several contexts, especially for the organizational settings.

Keywords: Dyadic creativity | Gender | Interpersonal coordination | Interpersonal synchronization | Joint action | Networked flow

Abstract: This review focuses on the design process of additively manufactured mesoscale lattice structures (MSLSs). They are arrays of three-dimensional (3D) printed trussed unit cells, whose dimensions span from 0.1 to 10.0 mm. This study intends to detail the phases of the MSLSs design process (with a particular focus on MSLSs whose unit cells are made up of a network of struts and nodes), proposing an integrated and holistic view of it, which is currently lacking in the literature. It aims at guiding designers' decisions with respect to the settled functional requirements and the manufacturing constraints. It also aims to provide an overview for software developers and researchers concerning the design approaches and strategies currently available. A further objective of this review is to stimulate researchers in exploring new MSLSs functionalities, consciously considering the impact of each design phase on the whole process, and on the manufactured product.

Keywords: additive manufacturing | design for additive manufacturing | design process | mesoscale lattice structures | multifunctional lattice structures

Abstract: The successful combination of aesthetic and engineering specifications is a long-standing issue. The literature reports some examples where this problem was achieved developing tools to support the automatic generation of new product shapes, embedding and linking predefined rule-sets. Notwithstanding, these kinds of tools are effective if and only if the relations among these specifications are known. Other complementary strategies act upstream by building a common ground: they aid in the formalisation of these specifications, fostering the use of a shared language and the same level of detail. This paper lies in between the previous approaches since its purpose is the description of a strategy to formalise the relations among aesthetic and engineering specifications and whose validities are not affected by the product variability. Indeed, fashion-driven products are subject to continuous innovations and changes. Therefore the identification of these predefined rule-sets is challenging. In detail, the paper objective is to build a high-level and long-lasting formalisation of these relations, based on topological and functional rules. To demonstrate the effectiveness of this approach, we developed a case study in the eyewear industry. We started considering the spectacle-frame functionality and derived the high-level formulation linking aesthetic and engineering specifications. We used this formulation to generate an abstraction of the frame geometry, i.e., an archetype, to be used as a reference for the design of new collections. We implemented the archetype through a MATLAB script, and we translated it into a design tool, to wit an Excel spreadsheet. The validity of both the archetype and the tool has been tested, in collaboration with an eyewear manufacturer, designing and manufacturing two new models of frames.

Keywords: Archetype | Design methods | Design specifications | Design tool | Eyewear industry | Product variability

Abstract: 3D virtual reconstruction of human body parts is nowadays a common practice in many research fields such as the medical one, the manufacturing of customized products or the creation of personal avatar for gaming purpose. The acquisition can be performed with the use of an active stereo system (i.e., laser scanner, structured light sensors) or with the use of a passive image-based approach. While the former represents a consolidated approach in human modeling, the second is still an active research field. Usually, the reconstruction of a body part through a scanning system is expensive and requests to project light on the patient’s body. On the other hand, the image-based approach could use multi-photo technique to reconstruct a real scene and provides some advantages: low equipment costs (only one camera) and rapid acquisition process of the photo set. In this work, the use of the photogrammetry approach for the reconstruction of humans’ face has been investigated as an alternative to active scanning systems. Two different photogrammetric approaches have been tested to verify their potentiality and their sensitivity to configuration parameters. An initial comparison among them has been performed, considering the overall number of points detected (sparse point cloud reconstruction, dense point cloud reconstruction). Besides, to evaluate the accuracy of the reconstruction, a set of measures used in the design of wearable head-related products has been assessed.

Abstract: We describe the implementation and preliminary validation of an interactive platform – COLLEGO – to investigate joint action in a goal-oriented collaborative task. The platform records the interaction sequence of two partners alternating their leader/follower role. Two sensitized wooden surfaces are placed in front of each participant, who can use 6 cubes to build the tower. Any time a cube is picked/released, time stamp (ms) and position of selected objects are recorded. A case study showing how data are collected and analyzed to study dyad performance during the task is described. Finally, potential applications of the proposed solution are discussed.

Keywords: Human-human interaction | Joint action | Performance | Sensors | Synchronization | Time-series analysis

Abstract: The paper deals with prototyping strategies aimed at supporting engineers in the design of the multisensory experience of products. It is widely recognised that the most effective strategy to design it is to create working prototypes and analyse user’s reactions when interacting with them. Starting from this consciousness, we will discuss of how virtual reality (VR) technologies can support engineers to build prototypes suitable to this aim. Furthermore we will demonstrate how VR-based prototypes do not only represent a valid alternative to physical prototypes, but also a step forward thanks to the possibility of simulating and rendering multisensory and real-time modifiable interactions between the user and the prototype. These characteristics of VR-based prototypes enable engineers to rapidly test with users different variants and to optimise the multisensory experience perceived by them during the interaction. The discussion is supported both by examples available in literature and by case studies we have developed over the years on this topic. Specifically, in our research we have concentrated on what happens in the physical contact between the user and the product. Such contact strongly influences the user’s impression about the product.

Keywords: Experience design | Interaction design | User experience | Virtual-mixed prototyping

Abstract: Joint action - the cooperation with other individuals to achieve a shared motor goal, is a crucial ability for human survival. This process takes place when actors are synchronized at a sensorimotor level. However, the experiential correlates of sensorimotor synchronization are not fully understood. The aim of this study was to investigate the relationship between the experience of flow and social presence in a sensorimotor collaborative task. 12 female couples (mean age = 22.33; S.D. = .815) and 12 male couples (mean age = 22.88; S.D. = .789) were involved in a tower-building task across 10 consecutive trials using the COLLEGO platform [1]. Couple members alternated their leader/follower role. Platform recorded time stamp (ms) and position of each selected object when it was picked/released, providing a measure of performance. Thereafter, participants’ level of flow (Flow State Scale), an intrinsically motivating state of consciousness, and social presence (Networked Minds Social Presence Inventory), i.e., the feeling of being with other Selves in a real or virtual environment, were assessed. Flow and Social presence correlated positively at a global level. Having clear goals was negatively associated with performance, while awareness and merging with one’s own actions correlated positively with performance. Task duration correlated negatively with attentive and behavioral dimensions of social presence, but positively with cognitive and emotional dimensions. Results are discussed according to the Networked Flow model assuming a positive correlation between social presence and flow at the base of the highest levels of collaborative performance.

Keywords: COLLEGO platform | Flow experience | Joint action | Networked flow model | Sensorimotor interaction | Social presence | Synchronization

Abstract: Design education is a highly debated topic since decades, yet the focus on multi-disciplinary classes has gained a paramount importance due to the multi-disciplinary nature of today's global challenges. This paper contributes to the discussion through the description of the Design Methods and Processes course at Alta Scuola Politecnica, an original educational experience jointly developed by Politecnico di Milano and Politecnico di Torino with a highly selected number of MS students from Architecture, Industrial Design and all branches of Engineering. After positioning this discussion with respect to the relevant literature, the paper describes the educational model of this course and the reflections made after 5 years of implementation. Students show to catch the essence of the design workflow thanks to the educational path structured as a problem-analysis-and-solving process. However, dealing with multi-disciplinary task demands a careful composition of students' teams since it can positively/negatively affect the learning experience as well as students' motivations.

Keywords: Design education | design practice | educational background | multi-disciplinary design | team working

Abstract: In this paper, we discuss the possibilities available as well as the challenge to be faced when designing for metal additive manufacturing through the description of an application of the Selective Laser Melting technology within the professional sports equipment field. We describe the redesign activity performed on the cam system of a compound bow, starting from the analysis of the functional, manufacturing and assembly constraints till the strategies applied to guarantee the printability of the object. This activity has thus provided the opportunity to analyse the difficulties currently encountered by practitioners when designing for additive manufacturing due to the lack of integrated design approaches and the high number of aspects that need to be simultaneously taken into account when performing design choices.

Keywords: Design for Additive Manufacturing | Metal Additive Manufacturing | Selective Laser Melting | Sports Equipment

Abstract: In this paper we describe the design of a smart alarm clock, conceived as a persuasive system to foster a sustainable urban mobility. Automatically retrieving and elaborating information available on the web, such as means of transport and weather forecast, the device is able to suggest to the user the most sustainable travelling solution, to help him/her to wake-up and reach the destination on time. Following a user-centered design approach the elaboration of the best travelling solution takes also into account, together with his/her next day appointments, user's needs and habits such as: The time he/she needs to get ready in the morning; his/her travelling preferences. A functional prototype has been built to test the effectiveness of the device using as a context the city of Milan.

Keywords: Design for sustainable behaviour | Multisensory product experience | Smart mobility | Sustainability | User centred design

Abstract: Innovation of fashion-related products implies the continuous search for new and appealing shapes and materials in a short period of time due to the seasonality of the market. The design and manufacturing of such products have to deal with a dimensional variability as a consequence of the new shapes. An additional difficulty concerns properly forecasting the technological behaviour of the new materials in relation to the manufacturing process phases. The control of dimensional variations requires time and resource intensive activities. Human's manual and visual inspection solutions are more common than automatic ones for performing such control, where skilled operators are typically the only ones capable of immediately facing non-standard situations. The full control of such variations is even more subtle and mandatory in the field of spectacles, which are fashion-related products and also medical devices. This paper describes an inspection system developed to monitor the dimensional variations of a spectacles frame during the manufacturing process. We discuss the methodological approach followed to develop the system, and the experimental campaign carried out to test its effectiveness. The system intends to be an alternative to current inspection practices used in the field, and also to provide a methodological approach to enable engineers to systematically study the correlations existing among the frame main functional and dimensional parameters, the material behaviour and the technological variables of the manufacturing process. Hence, the system can be considered a method to systematically acquire and formalise new knowledge. The inspection system consists of a workbench equipped with four high-quality commercial webcams that are used to acquire orthogonal-view images of the front of the frame. A software module controls the system and allows the automatic processing of the images acquired, in order to extract the dimensional data of the frame which are relevant for the analysis. A case study is discussed to demonstrate the system performances.

Keywords: Eyewear industry | Image processing | Inspection systems | Knowledge-based engineering | Product variability

Abstract: Today's world is facing numerous problems due to an uncontrolled waste of energy and of primary resources in general. To manage this, on one side designers are asked to improve the efficiency of products; on the other side, users must be trained toward a more sustainable lifestyle. Some researchers are exploring the idea of trying to change users' behavior while interacting with products in order to make it more sustainable. This trend is known as "design for sustainable behavior" applied to energy/resources consumption issues. Our idea is to stimulate users in changing their behavior by introducing a multisensory communication with the product. This communication is not meant as warning messages informing the users about wrong habits/actions or something like; instead, it should consist of sensorial stimuli able to naturally drive users in performing the right actions. However, before designing these stimuli, it is fundamental to highlight the aspects and conditions that do not allow users behaving in a sustainable way when interacting with products. In this paper we discuss about the aspects that could be useful to explore in order to retrieve the specifications to drive both the design and prototyping phases, so as to faithfully test the effectiveness of the feedback with final users.

Abstract: The paper proposes an alternative approach to well-known feedback solutions, such as visual displays or warning sound messages, to make users perceptually aware of the energy consumption occurring when using a product. The approach is grounded on the use of multisensory feedback interfaces that are designed to make the user experience the consumption process directly during the interaction with the product. Such multisensory feedback should be intended as indications, rather then alarms, so as to naturally guide users towards a more sustainable behaviour. The daily task of opening the fridge door has been used as case study. All the steps followed to ideate and test the effectiveness of the designed multisensory interfaces are discussed. The results demonstrate how even simple stimuli, such as a gradual colour change of the fridge cavity from a cold to a warm one, may be able to reduce the time users keep the fridge door open.

Keywords: Design for behaviour change | Human behaviour in design | Multisensory design | Sustainability | User centred design

Abstract: The objective of the paper is to present a case study to exploit interactive Virtual Prototypes (iVPs) for investigating the way humans experience products. This method can be used for "prototyping" new product experiences, for monitoring users' emotional reactions during the interaction and finally, for practically redesigning these experiences on the basis of the users' feedback. Products considered here are domestic appliances, where the experience consists of the interaction with their physical interfaces.

Abstract: In the product development process one of the crucial phases is the evaluation of the design of the product that must satisfy the marketing targets based on the users' needs analysis. It is commonly acknowledged that a product is successful if people like and buy it. In the phase of ideation of a new product, it is paramount to test functionality and performances as well as the users' appreciation and feeling towards the new product. More specifically, in the case of consumer products characterised by a plurality of offers, interaction and experience should be addressed in addition to function and aesthetics in the user studies. Recent research has focused on the study of the user's emotional reaction when interacting and experiencing products, which is correlated with the global appreciation of the product and of its attributes. This paper presents an emotional engineering methodology using interactive virtual prototyping for evaluating the user experience and the emotional response with newly designed products early in the development process. The methodology suggests a way to optimise those aspects at the product concept phase. © 2014 © 2014 Taylor & Francis.

Keywords: emotional engineering | product experience | virtual prototyping

Abstract: Designing physical interfaces, like the doors of consumer products, able to elicit a positive experience when interacting with them, is now becoming a key priority for design teams. One of the main difficulties of this activity consists of translating all the qualitative perceptual feedback that can be captured from the customers into quantitative specifications. Performing this translation is not an easy task since there are still no effective tools, methodologies or approaches able to guide designers in accomplishing this goal. To overcome this lack a reverse engineering-based approach is proposed. This one guides designers towards the modelling, parameterisation and reproduction of the behaviour of the product interface to be redesigned, within a multisensory virtual environment. The intent is to let the user experience different behaviours in order to ask them to identify the desired one or to express preferences for updating it in real-time according to indications provided. At the same time a detailed physics model, built by the designer, is used to convert this desired behaviour, into detailed quantitative design specifications. The method is defined as a reverse engineering one for two main reasons: first the new interaction is derived on the basis of the behaviour of an existing interface, taken as reference, and second a reverse engineering of the user's perceptual preferences is applied to derive new specifications. A case study is discussed to demonstrate the method effectiveness and to highlight its limitations. © 2014 Taylor & Francis.

Keywords: haptics | interactive systems | product experience | reverse engineering | virtual prototyping

Abstract: The term User Experience (UX) is commonly associated with interactive computer-based systems. Companies operating in the consumer market are recently discovering the importance of designing UX, and in particular multisensory UX, of any kind of system, and not necessarily high-tech products. One of the most effective ways to design UX is to enable users interacting with the prototype of the system during the design process, and in particular already during its initial stages. These prototypes should provide the same experience occurring while interacting with the corresponding real product. To this aim Virtual Prototypes (VPs) may be effectively used, especially in the early design stages when the activities are still in progress and changes are frequent. Multisensory UX can be effectively designed through VPs only if all the senses involved in the real interaction are recreated into the virtual simulation. To date, despite a growing interest of research and industry in the development and use of VPs, many applications are still limited to visual and sound simulations. This paper focuses on the use of VPs to design multisensory UX, concentrating on the introduction of the sense of touch in the simulation. The methodological approach as well as the development of a case study are described in the paper. © 2013 IEEE.

Keywords: Haptics | User experience design | Virtual prototyping

Abstract: The paper describes a methodological approach specifically developed to capture and transform the qualitative User Experience (UX) of a consumer product into quantitative technical specifications. Merging the potentialities of Virtual Prototypes (VPs) and Digital Mock-Ups (DMU), a flexible design scenario is built to interpret users' desires. Visual, sound and haptic stimuli are reproduced in order to let users live a realistic multisensory experience interacting with the virtual replica of the product. Parametric models are defined to acquire users' preferences while optimization algorithms are used to transform them into technical specifications. The aim of the approach is to propose a robust technique to objectify users' desires and enable their direct and active participation within the product development process. The methodology is derived merging insights coming from four case studies as well as indications available in literature. Specifically the paper describes how to design the multisensory UX with household appliance doors and drawers with a specific focus on the haptic/force feedback objectification. © 2013 The Design Society.

Keywords: Experience design | Haptic feedback | Human in the loop | User centred design | Virtual reality

Abstract: The paper describes the results of an on-going research activity whose aim is to allow companies, operating in the consumer goods market, to design the multisensory experience of their products. In case of the household appliances market, which is the research context of this study, the user experience derives from the interaction with specific product features such as the door, buttons, and drawers. Designing a good multisensory experience is complex since it means taking into account a combination of visual, hearing and haptic feedbacks a user perceives when interacting with the product. Virtual Reality offers the technologies to design and test that experience thought virtual prototypes, even if to date there is a lack of methodological approaches to practically guide and support this design activity. Relying on the results of previous authors' researches, the paper describes further methodological advances focused on making usable the proposed approach in the current design practice. The case study chosen to demonstrate the effectiveness of the method is a dishwasher door and the paper describes how to re-engineer the haptic feedback of a commercial model in order to make it more perceptually appealing at the moment of purchase. © 2013 CAD Solutions, LLC.

Keywords: Haptic interaction | Reverse engineering | User experience design | Virtual prototyping

Abstract: The paper describes a methodology that can be employed to perform the analysis of aspects related to human interaction with consumer products during the Product Development Process, thanks to the use of mixed prototypes. The methodology aims at helping designers to take decisions earlier compared to the current practice based on not easily modifiable physical prototypes. Authors' method considers the interaction with adaptable mixed prototypes as a possible validating procedure for product interaction-enabling features: a multimodal environment is created to perform these validations, integrating three sensorial modalities such as vision, hearing and touch. The paper firstly describes the requirements for the creation of the multimodal environment. Then it focuses on the opportunity of using an approach based on mixed prototypes rather than on completely virtual ones: the intent is to increase the level of "realism" of the simulation by overcoming limitations of actual technologies for the sense of touch. Finally, a case study is discussed, starting from the analysis of a commercial consumer product up to the interaction with the developed Mixed Prototype. The expected benefits for the product development process are highlighted. © 2013 CAD Solutions, LLC.

Keywords: Haptic interaction | Product virtualization | Virtual and mixed prototyping

Abstract: In this paper a 9-step method is proposed to study the evolution of technical systems. Merging the potential of TRIZ and patent analysis, a structured approach is defined to properly analyse the state of the art of a technology and retrieve useful insights to identify and structure new development strategies. Past-present evolutionary dynamics are quantitatively described, while indications for new possible development scenarios can be also extrapolated. Starting from a detailed breakdown of the technology under analysis, a list of evaluation parameters is defined to classify inventions and thus monitor the technology advancements by means of the TRIZ Laws of Engineering Systems Evolution. The aim of this study is to foster the diffusion of more reliable and systematic approaches to innovation especially in those industrial sectors where high risks and investment costs tend to favour short-term technological advances rather than long-term ones. Two case studies were developed within the context of the mining industry. Specifically, the study is part of a research project founded by the Chilean Economic Development Agency (CORFO) whose objective is to support companies of the Atacama region, in the identification of new technological opportunities to renew their production process. © 2013 - Society for Design and Process Science.

Keywords: Network of Evolutionary Trends (NET) | Technological Forecasting | Theory of Inventive Problem Solving (TRIZ)

Abstract: The fundamental steps in the development of electrical technologies have determined their strong diffusion in several applications that were previously hand operated and controlled. The household appliance industry is one of the sectors where this permeation had the major effects, fostering a continuous search for new design perspectives. Capturing such product evolution is fundamental in order to preserve knowledge coming from past experiences, which could act as a stimulus for new technical solutions or socio-economic analysis. Starting from the description of the dishwasher historical evolution, in this paper an approach to preserve such precious knowledge is presented: a functional representation of that knowledge is proposed end its role in modern design is discussed. © 2012 IEEE.

Keywords: dishwasher electric motor | functional basis | product evolution

Abstract: Extended enterprises require novel modes of organizing companies and managing collaboration. Although the promise of Information Communication Technologies to connect people, processes and information, it is worth to notice that current implementations are strongly document-oriented and do not enable flexible workflow management overcoming well-known inter-enterprise integration difficulties. The long-term goal of the research is the study of a new methodology and the development of dedicated software tools to facilitate the dynamic collaboration among 21 companies participating to a research project, funded by the Italian Economic Ministry, called CO-ENV. The definition of dynamic workflow system architecture represents the step forwards the implementation of a collaborative platform. Preliminary benchmarking of available systems and techniques, the product development process analysis of the project participant companies and a possible structure of the system are well illustrated. Examples of expected and unexpected exceptions are reported and differences between static and dynamic workflow management systems are discussed. © 2010 Springer-Verlag.

Keywords: Design process | Dynamic workflow | Extended enterprise | Product innovation | Product lifecycle management

Abstract: Since the assessment of the novelty, feasibility and value of new product ideas is highly subjective and uncertain, it is hard for companies to come up with a final product which successfully embodies customer needs, as well as company requirements. The major goal of this study is to propose a design and managerial step-based framework, moving from idea generation until the early steps of concept embodiment. Russian Theory of Inventive Problem Solving, together with multicriteria-based selection methods are employed. A case study from the household appliances industry is presented, discussing how to guide technical solutions implementation in new product ideas. Copyright © 2011 Inderscience Enterprises Ltd.

Keywords: Decision-making | Engineering conflicts | Idea generation | Product development | Product innovation | Project management

Abstract: Since the assessment of the novelty, feasibility and value of new product ideas is highly subjective and uncertain, it is hard for companies to successfully apply their innovation strategies and coming up with a final product which is able to concurrently and successfully embody both customers' needs as well as company requirements. Without forcing the innovation process in a more rigid and constrained structure, the implementation of selected formal approaches in specific innovation process stages may reduce and guide this uncertainty especially in design, managerial and decision-making activities. In this paper both a design and managerial step-based framework is proposed to help firms achieve greater success in their efforts to develop new products. Already existing and well assessed methods and techniques, together with more recent and under development ones, are employed in authors' framework, which moves from idea generation until the early steps of concept implementation. The main paper aim is then to persuade companies avoiding the classical and wasteful trial-and-error approach and make them more predictable and responsive to continuous change and uncertainty. A case study is discussed in order to demonstrate the framework effectiveness, specifically focusing on its last step, when the technical implementation of the new concept has to be performed. © Organizing Committee of TMCE 2010 Symposium.

Keywords: Concept implementation | Decision-making | Engineering conflicts | New product development process | Project management

Abstract: International competition intensification and product development process shortening have heightened the pressure to innovate, representing this issue nowadays a hallmark of all mature companies. Product innovation process is not always successful, due to its high level of uncertainty which makes difficult the best technical solutions selection, notably during the early stages of the product development process. Even if the decision making phase appears to be critical, formal and effective methodologies and tools are not often systematically applied in industry, and furthermore they lack both of rigor and of the capacity to really support human decision-making phases. In this paper a design paradigm is discussed in order to support the early phases of the product innovation process. Once evaluated the high potentials of TRIZ theory in supporting the idea generation phase, this work is focused on testing and improving the u-sDSP decision making approach in order to enable an agile implementation of this formal technique in the industrial context. The authors' proposed methodology is then applied to an industrial case study from the domestic appliances industry.

Keywords: Decision-based engineering design | Product innovation | Project screening

Abstract: Flexibility is the main keyword in order to face the rapid changing market requirements. Companies need methods and tools in order to implement flexibility over the whole product development process, from ideation to manufacturing. The proposed approach goes towards the concretization of the lean product design concept. It can be achieved if design alternatives and product modifications can be rapidly evaluated in terms of feasibility. resources. cost and time. The approach is based on a multilevel representation of the product structure. where functions. modules. assemblies and components are strictly interrelated. The complex representation requires suitable software tools in order to model and visualize the entire structure and support the easy user navigation. On the other hand it is necessary to define rules and operators to interact with the structure in order to make product changes and evaluate the possible impact. Finally. this system has to be integrated within the product development flow for exchanging data and information with CAD, PLM and ERP tools. In this paper the general approach is defined and the preliminary software solution is described.

Keywords: Change management | Change propagation | Lean design | Modularity

Abstract: It is well known that the global market is driving companies towards new productive paradigms oriented to product customization, agility and environmental sustainability. Companies have to face the problem of providing as much product variety as possible in order to rapidly satisfy a wide number of specific market segments. Even if the emerging automated agile production environments could enable them to manage product variety, in many productive fields, large waste streams, due to the practical difficulty of adapting the traditional production lines to product changes, are still present. At the same time a growing public concern for the environment, is forcing companies to investigate alternative uses for waste material. In this paper we present a practical example from the footwear industry in order to show how companies can successfully apply the concept of sustainable production taking into account the mass customization requirements but contemporarily reducing the material waste. The approach is focused on the combination in the same plant of two different production lines: one is dedicated to the primary production while the other uses the waste material to realize the secondary production. Copyright © 2008 by ASME.

Abstract: While incremental innovation is for most companies a well assessed process, radical product innovation is often handled with difficulty, mainly due to myriad obstacles in the idea-to cash process which limits company's ability to innovate. As a typical approach, engineers firstly try to find innovative solutions only inside their technological product space, basically thinking accordingly to their commonly assessed know-how. In this paper an industrial case is analyzed, showing how TRIZ methodology offers to technicians a systematic way to solve problematic contradictions and find effective ideas. © 2008 International Federation for Information Processing.

Keywords: Concept design | Idea generation | Radical innovation | TRIZ

Abstract: In this work we focus our research on the product design related aspects; currently we deal with modularity, product architecture and change propagation issues along the design process. In order to apply abstract concepts to design practise different approaches and tools have been proposed; anyway presently concrete software solutions and applications examples are still lacking. Companies modify their products for a number of reasons and rarely start from new ideas when designing. Due to the lack of suitable tools and methodologies designers are not aware of modifications impacts and propagations when trying to change or update a product. In this paper we present our research efforts in developing a methodology and the related software tool to support change management during the product redesign. It is conceived as guiding tool based on a product multilevel representation: from functional contents to implementation design; currently the designer can obtain a complete presentation of the product parts characteristics and their relations. In this way the resulting graphical model becomes a company tacit knowledge repository about the product. Operational functionalities are provided to support the designer during his activities. This work has been carried out and tested on the redesign process of a washing machine in collaboration with an Italian company, leader in house working appliances.

Keywords: Change propagation | Modular structure | Product architecture