Search Results (13)

This study aims to evaluate the feasibility of using Fused Deposition Modeling (FDM)/Fused Filament Fabrication (FFF) 3D printing for the emergency replacement of damaged components in the marine industry, focusing on mechanical properties, dynamic stiffness, and manufacturing efficiency. The authors’ research interests include the application of incremental and hybrid methods for the production of new, fully functional parts that constitute equipment for ships and yachts. The methods described in this paper can also be used to produce replacement parts in emergency conditions when there is a need for a temporary replacement of a damaged component. When testing parts made with 3D printing technology, the authors used modal analysis methods to estimate the dynamic stiffness of bracket support samples. The dynamic analysis of the tested parts was conducted using both the cavity method and the incremental method with FDM and FFF 3D printing. This study focused on determining their resonance curves. Based on these curves, the dynamic stiffness of the samples was calculated. Understanding the changes in dynamic stiffness of 3D printed parts depending on their degree of filling is one of the critical parameters from the point of view of the possibility of the safe operation of parts manufactured with this method. The results show that the dynamic stiffness of 3D printed parts depends significantly on the infill percentage. This article also presents the results of a simplified technical and economic analysis of the bracket support manufacturing samples produced by machining, incremental, and hybrid methods. The quality parameters of the geometric structure of the parts made with the manufacturing methods analyzed in this paper are also compared with each other. Full article

Modern design products are increasingly complex and emotionally significant, demanding versatile and collaborative customization. However, a literature and commercial review reveals a limited availability of flexible, multi-user, photorealistic Virtual Reality (VR) systems for product configuration. We introduce MAGIC (Multi-user Advanced Graphic Immersive Configurator), a collaborative platform combining realistic graphics with ergonomic validation using digital avatars, addressing the limitations of 2D visualization and existing tools. MAGIC is evaluated in a yacht design case study involving 30 participants in an immersive, co-located configuration of a sailing yacht to assess the system’s usability and the potential of VR for customizing complex products. Results show MAGIC’s feasibility in supporting multi-user configuration (100% success rate) and achieving a strong usability score (SUS = 80.83). User feedback highlights that high-quality graphics and additional content significantly enhance immersion and user engagement. However, encountered challenges with navigation methods and spatial perception indicate areas for improvement. MAGIC’s collaborative and immersive capabilities can be extended to other industries demanding proactive customer engagement in the customization of large, heavy products and ergonomic design. Moreover, by promoting prototype dematerialization and providing an interactive remote tool for end users, MAGIC offers potential environmental and economic benefits to boost the competitiveness of small and medium enterprises (SMEs). Full article

The Mediterranean superyacht industry significantly contributes to the region’s economy, but its rapid growth has raised serious environmental concerns. This study compares the emissions, waste management, and biodiversity protection of two marinas located in Sicily, Italy, and the Balearic Islands, Spain. A survey assessing the carbon footprint and water quality was distributed to the management of the marinas. The collected data were analysed and translated into tonnes of CO₂ equivalent using emission factors. By calculating the carbon and water footprints of the two marinas, this study aimed to understand the environmental impact of port-related operations. The JMarinas Environmental Decision Support System and a P-Mapping/Pareto approach were used to identify pollutant sources, following Pareto’s principle. The findings indicated that the primary operations of the marina sector are the main sources of pollution, with significant contributions from supporting activities. This study clarifies the origins of CO₂ and pollution in marina operations, enabling the authors to recommend the close supervision of all recreational boating activities to reduce CO₂ emissions and environmental degradation. By adopting these recommendations, policymakers, marina operators, and yacht owners can ensure the long-term sustainability of Mediterranean marinas. Full article

In addition to the traditional uses of plywood, such as furniture and construction, it is also widely used in areas that benefit from its special combination of strength and lightness, particularly as a construction material for the production of finishing elements of campervans and yachts. In light of the current need to reduce emissions of climate-damaging gases such as CO₂, the use of lightweight construction materials is very important. In recent years, hybrid structures made of carbon fibre-reinforced plastics (CFRPs) and metals have attracted much attention in many industries. In contrast to hybrid metal/carbon fibre composites, research relating to laminates consisting of CFRPs and wood-based materials shows less interest. This article analyses the hybrid laminate resulting from bonding a CFRP panel to plywood in terms of strength and performance using a three-point bending test, a static tensile test and a dynamic analysis. Knowledge of the dynamic characteristics of carbon fibre-reinforced plywood allows for the adoption of such cutting parameters that will help prevent the occurrence of self-excited vibrations in the cutting process. Therefore, in this work, it was decided to determine the effect of using CFRP laminate on both the static and dynamic stiffness of the structure. Most studies in this field concern improving the strength of the structure without analysing the dynamic properties. This article proposes a simple and user-friendly methodology for determining the damping of a sandwich-type system. The results of strength tests were used to determine the modulus of elasticity, modulus of rupture, the position of the neutral axis and the frequency domain characteristics of the laminate obtained. The results show that the use of a CFRP-reinforced plywood panel not only improves the visual aspect but also improves the strength properties of such a hybrid material. In the case of a CFRP-reinforced plywood panel, the value of tensile stresses decreased by sixteen-fold (from 1.95 N/mm² to 0.12 N/mm²), and the value of compressive stresses decreased by more than seven-fold (from 1.95 N/mm² to 0.27 N/mm²) compared to unreinforced plywood. Based on the stress occurring at the tensile and compressive sides of the CFRP-reinforced plywood sample surface during a cantilever bending text, it was found that the value of modulus of rupture decreased by three-fold and the value of the modulus of elasticity decreased by more than five-fold compared to the unreinforced plywood sample. A dynamic analysis allowed us to determine that the frequency of natural vibrations of the CFRP-reinforced plywood panel increased by about 33% (from 30 Hz to 40 Hz) compared to the beam made only of plywood. Full article

The significant and ongoing growth of the yacht charter sector plays a crucial role in the tourism industry as a whole, especially in nautical tourism. This study provides a detailed analysis of the yacht charter market, focusing on the opportunities for and challenges in its sustainable growth, with a specific emphasis on Andalusia, Spain. The main objective is to align the yacht charter offer with customer preferences, enabling yacht owners or companies to make more informed decisions and contributing to the sustainability of the sector and the region. Using machine learning techniques, researchers have analyzed extensive datasets to identify patterns in customer behavior and yacht characteristics. Industry companies and yacht owners can use the results of this research to develop more effective marketing strategies, improve customer experience, and efficiently manage their fleets, thus directly contributing to the socio-economic and environmental sustainability of mooring locations. Furthermore, this research enhances the understanding of yachting tourism, laying the groundwork for future research and developments in the industry. Full article

This paper explores applications of additive manufacturing (AM) for producing structural components in the yacht industry. Several case studies illustrate how AM is applied to create lightweight composite panels and complex geometries that are challenging to produce with traditional methods. Experimental and simulation studies demonstrate the mechanical performance of AM-produced parts. The key benefits demonstrated include design flexibility and zero-tool manufacturing. The potential roles of AM in addressing industry challenges, such as customisation possibilities and more sustainable production methods, are discussed. The case studies indicate the technical feasibility of 3D printing for functional yacht applications across various scales. Overall, AM shows promise in revolutionising design and manufacturing approaches by enabling optimised structures and on-demand production without traditional manufacturing constraints. This research study highlights the technology’s role in evolving yacht design and production practices. Full article

Nowadays, the industrial world is undergoing a disruptive transformation towards more environmentally sustainable solutions. In the blue economy, this new approach is not only expressed in the domain of actual vessels, but also in the development of charging infrastructure, displaying a notable transition towards more eco-friendly solutions. The key focus lies in adopting flexible power systems capable of integrating renewable energy sources and storage technologies. Such systems play a crucial role in enabling a shift towards low-emission maritime transport. The emissions reduction goal extends beyond onboard shipboard distribution systems, encompassing also the design of supplying platforms and marinas. This study explores the implementation of a controlled DC microgrid tailored to efficient management of power flows within a yacht marina. Once having established the interfaces for the vessels at berth, the integration between the vessels, the onshore photovoltaic plant and the battery storage unit is made possible thanks to the coordinated management of multiple power converters. The overarching goal is to curtail reliance on external energy sources. Within this DC microgrid framework, a centralized controller assumes a pivotal role in orchestrating the power sources and loads. This coordinated management is essential to achieve sustainable operations, ultimately leading to the reduction of emissions from both ships and onshore power plants. Full article

Composites are materials that are widely used in industry, including yachting, railway and aviation. The properties of these materials can be modified by changing the type of reinforcement, the type of matrix, as well as the use of additives in the form of fillers and nanofillers that improve their mechanical or specific parameters. Due to the fact that these materials are often used for important structures, computational models using FEM tools may not be sufficient to determine the actual strength parameters, and what is more, to check them during operation. When designing structures made of composite materials, it is necessary to use high safety factors due to their behavior under several different types of loads, which is still difficult to determine precisely. This situation makes these structures much heavier and characterized by much higher strength properties than those that would actually be needed. In this article, the Kolmogorov-Sinai (K-S) metric entropy was used to determine the transition from the elastic to the viscoelastic state in GFRP (glass fiber reinforced polymer) composite materials without and with the addition of nanoaluminum, during a static tensile test. Additionally, the acoustic emission method was used during the research. This signal was further processed, and graphs were made of the number of events and the amplitude as a function of time. The obtained values were plotted on tensile graphs. The influence of the nano-filler on these parameters was also analyzed. The presented results show that it is possible to determine additional parameters affecting the strength of the structure for any composite materials. Full article

Biofouling is a significant problem in the aquaculture and marine shipping industries; thus, various antifouling methods have been developed to prevent the resultant economic losses. In the present study, the superhydrophobic surface of a lotus leaf was bio-mimicked to achieve antifouling. Specifically, fabric substrates with and without superhydrophobic coatings on the surface were installed on the Tongyeong yacht in December 2020 (group A) and April 2021 (group B), and the coverage of the attached invertebrates was recorded every month until August 2021. The coverage of solitary ascidians (Ascidiella aspersa and Ciona robusta) and branching bryozoans (Bugula neritina) was lower on the coated substrates than on the non-coated ones, and coating or non-coating was significantly correlated with the extent of coverage. Superhydrophobic substrates with a low surface energy and micro–nano dual structure may be unsuitable for the attachment of larvae. Therefore, superhydrophobic coating is a more effective and simpler method of antifouling for certain taxa than other antifouling strategies. However, the antifouling effect of the superhydrophobic substrate in group A reduced after 5 months from the first installation; thus, the durability of the antifouling coating should be further improved, and solving this problem remains a major task, necessitating further research. Full article

Clarifying the current constraints facing the development of yachting tourism in China is key to ensuring the healthy development of this niche industry. This study uses grounded theory as a theoretical basis to conduct qualitative research and applies semi-structured interview techniques to examine stakeholders’ views on the constraints on the development of yachting tourism in China, from the perspectives of both yachting supply and demand. MAXQDA2020 qualitative analysis software was used to determine the main constraints. The study identified seven of these constraints, including policies and regulations, government behaviors, the social development environment, marketing, infrastructure, expertise and manpower, and culture. Based on these constraints, and the recommendations for improving yachting tourism proposed by the interviewed stakeholders, the study offers seven strategies for the further development of yachting tourism, which have practical significance for this development both in China and abroad. Full article

Due to the unique properties of polymer composites, these materials are used in many industries, including shipbuilding (hulls of boats, yachts, motorboats, cutters, ship and cooling doors, pontoons and floats, torpedo tubes and missiles, protective shields, antenna masts, radar shields, and antennas, etc.). Modern measurement methods and tools allow to determine the properties of the composite material, already during its design. The article presents the use of the method of acoustic emission and Kolmogorov-Sinai (K-S) metric entropy to determine the mechanical properties of composites. The tested materials were polyester-glass laminate without additives and with a 10% content of polyester-glass waste. The changes taking place in the composite material during loading were visualized using a piezoelectric sensor used in the acoustic emission method. Thanks to the analysis of the RMS parameter (root mean square of the acoustic emission signal), it is possible to determine the range of stresses at which significant changes occur in the material in terms of its use as a construction material. In the K-S entropy method, an important measuring tool is the extensometer, namely the displacement sensor built into it. The results obtained during the static tensile test with the use of an extensometer allow them to be used to calculate the K-S metric entropy. Many materials, including composite materials, do not have a yield point. In principle, there are no methods for determining the transition of a material from elastic to plastic phase. The authors showed that, with the use of a modern testing machine and very high-quality instrumentation to record measurement data using the Kolmogorov-Sinai (K-S) metric entropy method and the acoustic emission (AE) method, it is possible to determine the material transition from elastic to plastic phase. Determining the yield strength of composite materials is extremely important information when designing a structure. Full article

Despite the high number of active small and medium enterprises (SMEs) in all sectors, current studies have barely developed investigations on the sustainability of their business models so far. The aim of this study was thus to bridge the gap between sustainable business models of SMEs in the service industry, to uncover the challenges that SMEs face when seeking business model reconfiguration toward sustainability. More specifically, the empirical investigation adopted a case study research design in the context of yacht tourism, as one business form among many within the tourism industry and thus within the broader category of the service industry. Interviews were conducted with seven European SMEs, whose business models were analyzed through the lens of the triple bottom line and sustainability challenges in their business models. The results display a varied typology of case studies, where business model components reveal diverse expressions of facing sustainability challenges. The work discusses reported findings with a cross-case comparison among detected business models and outlines a list of propositions for sustainable business models of SMEs. The paper contributes in continuing the discourse on sustainable business models, adopting the perspective of the challenges for SMEs and offers food for thought for managers of SMEs in comparing their own business with the identified business model types. Full article

Aluminum Alloy 6061 components are frequently manufactured for various industries—aeronautics, yachting, and optical instruments—due to their excellent physical and mechanical properties, including corrosion resistance. There is little research on the mechanical tooling of AA6061 and none on its structure and properties and their effects on surface roughness after finish turning. The objective of this comprehensive study is, therefore, to ascertain the effects of both the modern method of hardening AA6061 shafts and the finish turning conditions on surface roughness, Ra, and the minimum machining time for unit-volume removal, T_m, while also establishing the cost price of processing one part, C. The hardening methods improved both the physical and the mechanical material properties processed with 2, 4, and 6 passes of equal channel angular pressing (ECAP) at room temperature, using an ECAP-matrix with a channel angle of 90°. The reference workpiece sample was a hot extruded chip under an extrusion ratio (ER) of 5.2 at an extrusion temperature of 500 °? (ET = 500 °C). The following results were obtained: grain size in ECAP-6 decreased from 15.9 to 2.46 μm, increasing both microhardness from 41 Vickers hardness value (HV) to 110 HV and ultimate tensile strength from 132.4 to 403 MPa. The largest decrease in surface roughness, Ra—70%, was obtained turning a workpiece treated with ECAP-6. The multicriteria optimization was computed in a multilayer perceptron-based artificial neural network that yielded the following optimum values: the minimal length of the three-dimensional estimates vector with the coordinates Ra = 0.800 μm, T_m = 0.341 min/cm³, and ? = 6.955 $ corresponded to the optimal finish turning conditions: cutting speed v_c = 200 m/min, depth of cut a_p = 0.2 mm, and feed per revolution f_r = 0.103 mm/rev (ET-500 extrusion without hardening). Full article