Despite the large diffusion of additive manufacturing, and markedly fused filament fabrication, some quality aspects of the 3D printed parts have not been dealt with sufficiently. This applies particularly to geometric accuracy and the influence process parameters have on it. The paper describes an experiment in which 27 copies of a part were manufactured by means of a desktop fused filament fabrication device while manipulating layer thickness, printing speed, and number of contours. The effect of such process parameters on five typologies of geometric deviations and the duration of the printing process was assessed. While all the process parameters showed effects on both the printing time and some geometric deviations, the number of contours resulted as the most critical factor. The paper includes a proposal to optimize geometric accuracy and the rapidity of the process, which foresees the maximization of the number of contours, the minimization of the layer thickness, and the use of an intermediate value for printing speed.

Eco-designed products can contribute to sustainable development if consumers choose them rather than the less environmentally friendly alternatives and if they are used properly. However, eco-design methods have so far failed to address the issue of unsustainable behaviors, whose sources have not been recognized. In light of this deficiency, the authors have analyzed a large number of eco-designed products with the aim to capture the possible unsustainable behaviors arising from their use and consumption. The subsequent characterization of unsustainable behaviors has led to the creation of a framework of unsustainable behaviors, which has been subjected to the evaluation of a pool of experts in the field. In its final version, the framework includes nine classes of unsustainable behaviors, which are categorized into the corresponding product lifecycle phases (purchase, use, end of life), and different kinds of undesired effects (harmful, insufficient, excessive) based on the TRIZ-oriented functional analysis. The classes, whose significance has been checked in the literature, include frequent causes of unsustainable behaviors and corresponding examples. Through the framework, designers can take into due account the possible circumstances that would prevent their developed products from being prone to unsustainable behaviors. In a future step, the classes of unsustainable behaviors are to be linked with indications arising from Design for Sustainable Behavior.

Sustainability-related information affects people’s choices and evaluation. The literature has made significant efforts to understand the best ways of delivering this kind of information to shape consumer behavior. However, while most studies have focused on packaged products and direct information provided through eco-labels, preferences could be formed differently in other design domains. The paper investigates the effect of the perceived amount of indirect information on the evaluation of an architectural artefact. A sample of 172 participants visited a locally produced mobile tiny house, made with a considerable amount of sustainable materials. The same participants answered a questionnaire about their perceived knowledge, quality, appropriateness and sustainability of the tiny house. The general level of knowledge of the tiny house was used as a proxy of the amount of indirect information received. Although the knowledge of the tiny house was generally low, ratings regarding the other dimensions were overall extremely positive. In particular, no evident relation was found between knowledge of the tiny house and sustainability, while the latter is significantly linked to quality aspects. These outcomes deviate from the evidence from other studies; this might be due to indirect vs. direct information and the peculiarity of the study carried out in the field of buildings. The gathered demographic and background data of the participants make it possible to highlight the role played by gender and age in affecting the evaluations, but the absence of a significant impact of experience in the field, education and origin. The results are compared with findings related to the evaluation of sustainable products and green buildings in particular.

The rising complexity of industrial systems following the Industry 4.0 era involves new challenges and the need for innovative solutions. In the context of arising digital technologies, Digital Twins represent a holistic solution to overcome heterogeneity and to achieve remote and dynamic control of cyber–physical systems. In common reference architectures, decision-making modules are usually integrated for system and process optimization. This work aims at introducing the adoption of a multi-purpose simulation module in a Digital Twin environment, with the objective of proving its versatility for different scopes. This is implemented in a relevant laboratory environment, strongly employed for the test and validation of mechatronic solutions. The paper starts from revising the common techniques adopted for decision-making modules in Digital Twin frameworks, proposing then a multi-purpose approach based on physics simulation. Performance profiling of the simulation environment demonstrates the potential of real-time-capable simulation while also revealing challenges related to computational load and communication latency. The outcome of this work is to provide the reader with an exemplary modular arrangement for the integration of such module in Digital Twin applications, highlighting challenges and limitations related to computational effort and communication.