Designs, Volume 9, Issue 1 (February 2025) – 17 articles

It is essential to elucidate the shear mechanical behavior of structural planes to assess the risk to rock masses and protect them from shear failure. Current research on shear mechanical behavior is focused on isotropic structural planes with the same lithology on both sides. However, anisotropic structural planes, commonly found in nature, may exhibit unique mechanical behavior that differs from isotropic structural planes. Therefore, it is necessary to study the factors affecting the shear strength of the anisotropic structural planes. In this paper, the direct shear numerical tests on anisotropic structural planes were carried out using the three-dimensional distinct element code (3DEC) based on the laboratory test. The numerical test results illustrate that the error between the peak shear strength of the numerical test and the laboratory test is basically within 10%. The shear stress-displacement curves of the numerical and laboratory tests are similar, which verifies the accuracy of the numerical test. According to the Barton standard sections, anisotropic structural plane models with different roughness and size were established, and the direct shear numerical tests with different normal stresses were carried out. To predict the peak shear strength of the anisotropic structural planes, one hundred and eighty-one sets of direct shear numerical test data were selected. Normal stress, roughness, compressive strength of soft and hard rock masses, basic friction angle of soft and hard rock masses, and structural plane size were used as input parameters to establish a back propagation (BP) neural network model. The research results show that, under identical conditions, the shear strength of the anisotropic structural planes decreases as the structural plane size increases. On the contrary, the shear strength increases with the increasing structural plane roughness and normal stress. For the BP neural network prediction model, the root mean square error (RMSE) and coefficient of determination (R²) of the training set are 0.441 and 0.957. For the test set, the RMSE is 0.489, and R² is 0.947, which indicates that the predicted values are in good agreement with the actual values. Full article

This study is the result of the need to research the visualization of brainwaves. The aim is based on the idea of using generative AI art systems as a method. Data visualization is an important part of understanding the evolution of the world around us. It offers the ability to see a representation that goes beyond numbers. Generative AI systems have gained the possibility of helping the process of visualizing data in new ways. This specific process includes real-time-generated artistic renderings of these data. This real-time rendering falls into the field of brainwave visualization, with the help of the EEG (electroencephalogram), which can serve here as input data for Generative AI systems. The brainwave measurement technology as a form of input to real-time generative AI systems represents a novel intersection of neuroscience and art in the field of neurofeedback art. The main question this paper hopes to address is as follows: How can brainwaves be effectively fed into generative AI art systems, and where can the outcome lead, in terms of progress? EEG data were successfully integrated with generative AI to create interactive art. The installation provided an immersive experience by moving the image with the change in the user’s mental focus, demonstrating the impact of EEG-based art. Full article

Foot disorders affect approximately 10% of adults, with plantar heel pain significantly impacting foot-related quality of life and altering walking patterns. Flat feet, characterized by a lack of longitudinal arches, can lead to fatigue during walking. This study aims to develop 3D-printed shoe insoles tailored to the needs of patients. The design process incorporates Quality Function Deployment (QFD), Theory of Inventive Problem Solving (TRIZ), and Analytic Hierarchy Process (AHP) methods to create insoles that alleviate concentrated loads while meeting patient requirements. The AHP analysis indicated that patients prioritize insoles that effectively manage pressure distribution to achieve optimal functionality. QFD and TRIZ facilitated the identification of four product alternatives and production specifications. The analysis indicated that 3D-printed insoles made from TPU filament with 20% auxetic infill best align with patient preferences. This auxetic TPU option emerged as the top choice, achieving a priority value of 0.2506 due to its superior functionality and comfort. Load distribution measurements confirmed that TPU with auxetic infill resulted in the lowest load distribution, with a standard deviation of 0.1434 and a 25.4% reduction in maximum load compared to conditions without the insole. Full article

Historically, urban development has always been centered on coastal areas, with access to waterbodies—seas, rivers and canals—being a significant advantage for movement and trade. With most of the world’s megapolises located on coasts, land reclamation offers a solution for the expansion of city centers which are otherwise restricted by the coastline. This study aims to define the current understanding of urban regeneration and development on reclaimed lands, addressing the basic questions of what, why and how. This study aims to assess urban regeneration on reclaimed coastal land based on the principles of sustainable development defined by existing studies. The literature review establishes a theoretical framework and defines performance-based benchmarks for identifying spatial indicators of urban development. Composite indicators, namely open space coverage, land use mix, the percentage of coast for people, accessibility to public transportation and amenities, the availability of pedestrian paths and cycling tracks and adequate road networks, are considered for this framework. The conclusions are drawn based on the results of an analysis of spatial layout using a GIS as a tool to map and empirically measure each indicator. The framework is validated using a major land reclamation project, West Bay, in the coastal urban area of Doha in Qatar. The results determine that West Bay has achieved a good level of sustainability, although there are areas that could be enhanced to improve the overall sustainability of urban development further. These findings can serve as a guide for policymakers and various stakeholders for sustainable urban planning on reclaimed coastal lands. Full article

The hardware-in-the-loop (HIL)-based virtual calibration technology for power machinery significantly enhances the efficiency and flexibility of electronic controller calibration, reducing dependency on physical experiments and lowering development costs. This paper presents an independently developed modular virtual calibration platform, designed based on the ISO/IEC 42010 architecture approach and the V-Model development process. The platform adopts a modular layered architecture comprising the physical layer, communication layer, model layer, software layer, and application layer. Each layer is independently developed and seamlessly integrated, ensuring excellent scalability and maintainability. Through performance validation conducted under steady-state and transient operating conditions of the diesel/natural gas dual-fuel engine electronic control unit (ECU), experimental results demonstrated that the platform possesses high computational accuracy, rapid response capability, and stable operation across different scenarios. The experiments validated that the platform can effectively replicate the real behavior of the controlled units in a virtual environment, confirming its adaptability and reliability. The platform offers an efficient and reliable solution for power machinery controller calibration. Full article

Container transport is one of the most promising modes of international freight transport. Railway container transport is mainly carried out using flat cars. Container cars can be damaged under the most unfavorable operating load conditions of a 1520 mm track gauge, i.e., shunting collisions. In this context, an improvement to the supporting structure of flat cars is proposed to ensure their strength, involving the installation of special superstructures in their cantilever parts to limit the movement of the containers. The choice of the superstructure profiles was made on the basis of the section modulus of their components. Mathematical modeling of the dynamic loading of a flat car with containers in the event of a shunting collision was carried out. The determined value of acceleration was taken into account in the calculation of the strength of the load-bearing structure of the flat car. It was found that the maximum stresses were 24% lower than the allowable stresses. Therefore, the strength condition of the flat car was met. The results of this study will contribute to reducing damage to container transport vehicles in service, to the formulation of recommendations for their construction and to an increase in their profitability, including in international transport. Full article

This research explores the design of a system for monitoring driver drowsiness and supervising seat belt usage in interprovincial buses. In Peru, road accidents involving long-distance bus transportation amounted to 5449 in 2022, and the human factor plays a significant role. It is essential to understand how the use of non-invasive sensors for monitoring and supervising passengers and drivers can enhance safety in interprovincial transportation. The objective of this research is to develop a system using a Raspberry Pi 4 and Arduino Nano that allows for the storage of monitoring data. To achieve this, a conventional camera and MediaPipe were used for driver drowsiness detection, while passenger supervision was carried out using a combination of commercially available sensors as well as custom-built sensors. RS485 communication was utilized to store data related to both the driver and passengers. The simulations conducted demonstrate a high level of reliability in detecting driver drowsiness under specific conditions and the correct operation of the sensors for passenger supervision. Therefore, the proposed system is feasible and can be implemented for real-world testing. The implications of this research suggest that the system’s cost is not a barrier to its implementation, thus contributing to improved safety in interprovincial transportation. Full article

This study experimentally investigates the effects of freezing conditions on the shear characteristics of geomembrane–soil interfaces, employing a temperature-controlled direct shear apparatus. The findings reveal significant variations in shear stress–shear displacement patterns at the soil–geomembrane interface under different thermal conditions. At positive temperatures, the interface manifests strain hardening behavior, whereas at negative temperatures, it transitions from weak softening at low normal stress to strong strain softening at high normal stress. The shear displacement–normal displacement curves under varying temperature and normal stress conditions demonstrate dilatant behavior, with initial increases in normal displacement followed by a decrease as temperature drops. Notably, the interface friction angle is markedly higher at negative temperatures compared to positive, undergoing an initial increase, a period of stable development, and a subsequent rise with further temperature reduction. The average shear strength ratio at the interface is observed to be as low as 0.58 at 20 °C, approaches unity between −2 °C and −6 °C, and exhibits a significant increase at −10 °C. These findings are helpful for the application of geomembranes in frozen soil engineering. Full article

This paper explores the use of physical scale models as immersive prototypes in the design and development of Spatial Augmented Reality (SAR) environments. SAR integrates digital projections with physical spaces, offering benefits for spatial reasoning and coordinated activities. However, designing SAR systems at full scale presents challenges in testing and refinement due to their complex physical–digital properties. To address this, we developed augmented miniature environments for two case studies: an in-store retail navigation system and a manufacturing assembly process. These models effectively materialized SAR’s most important experiential qualities at a manageable scale, enabling the exploration of spatial relationships, coordinated user activity, and system functionality in a tangible and accessible way. The miniatures facilitated collaborative design, providing a shared medium for stakeholders to visualize and experiment with SAR applications. This paper presents augmented miniatures as effective tools for SAR design that foster creative exploration and communication, and highlights opportunities for future research in combining these models with digital prototyping technologies. Full article

This paper is focused on understanding how a wave was transmitted along arrays joined with rivets. The arrays were made of steel plates, and each section was joined to the other with five rivets. A total of three arrays were studied, which were compounded by one, two and three steel plates. To determine the wave transmission, a laser, a lens and a camera were set up in the experiment to calculate the in-plane motion both while the structure was still and during the indirect collisions. Results were studied by means of the general theory of elasticity coupled with spectral analysis from a general mathematical model; the latter fitted all the responses with a mean of 98% accuracy. Full article

In construction, materials of various kinds such as steel, concrete, and timber have consistently been pertinent. Yet the ambition to provide a more sustainable, effective and cost-efficient solution, in a world where the environment is becoming a growing consideration, is at the forefront of many minds. With bamboo being the fastest-growing plant in the world and having many structurally desirable qualities, it may have the potential to become part of Australia’s primary construction materials due to its ability to thrive in Australia’s tropical and sub-tropical climates. With the growing popularity of bamboo in structural applications, this study aims to identify the primary indicator of compressive load capacity of Phyllostachys pubescens, which may facilitate the use of intact whole culms in the Australian construction industry. To investigate the potential of bamboo culms for construction, an indicator for the ultimate load capacity in compression (B_u) parallel with the grain of 5-year-old construction-ready Phyllostachys pubescens (Moso bamboo) culms was examined. This was achieved by testing the load capacity of culm representatives with consideration to the number and location of nodes, culm diameter, wall thickness, moisture content, and density of the bamboo culm. Bamboo representatives from the top and bottom of the culm were cut to an aspect ratio of 1:2 (diameter to length) and compressed in a Universal Testing Machine at a rate of 0.1 mm/min. Diameters of 60 mm, 80 mm, 100 mm, and 120 mm were tested. From the investigation results, the principal indicator for the compressive load capacity of a bamboo culm is deduced. As an anisotropic material, it is important to note any relevant trends in an attempt to categorise bamboo, for the development of guidelines for bamboo usage in construction. Key findings indicate a positive correlation with diameter and wall thickness to compression load capacity; however, wall thickness was a more accurate indicator with a higher coefficient of determination, while diameter exhibited more anomalies. The top of the culm representatives provided very high accuracy for determining compressive load capacity through wall thickness and were shown to provide lower load capacity relative to their bottom counterparts. This suggests that using the wall thickness at the top of the culm as an indicator for compressive load capacity to be the most accurate, and a safe and conservative approach. Density and moisture content as independent indicators had a negative correlation with load capacity; however, it was observed to be a poor indicator of load capacity providing very low accuracy. The number of nodes affected load capacity in relation to wall thickness, with two nodes showing slightly lower and 0 nodes slightly higher capacity; however, the effect was insignificant, as representatives with one node showed greater deviation. The location of nodes impacted perceived load capacity, with centrally located nodes observed to provide larger load capacities in comparison to representatives with top or bottom located nodes. All failures occurred in a controlled manner, exhibiting primarily ductile failure. Given the B_u for the tested segments is relatively high, Moso bamboo has the potential to be an applicable construction material provided appropriate guidelines are developed. Full article

Hydraulic mechanical continuously variable transmission (HMCVT) is widely used in powerful tractors due to its excellent performance. This paper aims to find universal methods for analyzing and optimizing the transmission efficiency of HMCVT. The energy efficiency improvement of HMCVT is important for the economy of powerful tractors. Firstly, by correctly analyzing the transmission efficiency of HMCVT, the transmission efficiency during the operation of HMCVT can be accurately calculated. Secondly, an improved NSGA-II genetic algorithm was adopted to achieve dynamic optimization of shifting points through transmission parameter combination optimization, ensuring smooth shifting while improving overall transmission efficiency. According to the transmission efficiency simulation platform, the accuracy of the transmission efficiency calculation was verified. Adopting an improved NSGA-II genetic algorithm to continuously optimize the design of HMCVT configurations achieves dynamic optimization of HMCVT parameters without being limited by shifting speed. The specific HMCVT structure proposed in this study can meet the requirements of a three-speed continuously variable transmission at speeds of 0–50 km/h. Meanwhile, the improved NSGA-II genetic algorithm can effectively provide support for the design of various HMCVT powertrain systems. Full article

The rapid advancement of model-based simulation has driven the increased adoption of virtual testing in power machinery, raising demands for high accuracy and real-time signal processing. This study introduces a real-time signal simulation and acquisition system leveraging field-programmable gate array (FPGA) technology, designed with flexible scalability and seamless integration with NI hardware-based test systems. The system supports various dynamic signals, including position, injection, and ignition signals, providing robust support for virtual testing and calibration. Comprehensive testing across scenarios involving oscilloscopes, signal generators, and the rapid control prototyping (RCP) platform confirms its high accuracy, stability, and adaptability in multi-signal processing and real-time response. This system is a state-of-the-art and extensively virtual field-tested platform for both power systems and power electronics. Full article

The wind turbine gearbox, used as a multiplier, is one of the main components directly related to a wind turbine’s efficiency and lifespan. Therefore, strict control of the gearbox and its manufacturing processes and even minor improvements in this component strongly and positively impact energy production/generation over time. Since only some papers in the literature analyze the mechanical aspect of wind turbines, focusing on some parts in depth, this paper fills the gap by offering an analysis of the gearbox component under the highest amount of stress, namely relating to the sun shaft, as well as a more holistic analysis of the main gear drives, its components, and the lubrification system. Thus, this work diagnoses the fracture mechanics of a 1600 kW gearbox to identify the main reason for the fracture and how the chain of events took place, leading to catastrophic failure. The diagnoses involved numerical simulation (finite element analysis—FEA) and further analysis of the lubrication system, bearings, planetary stage gears, helical stage gears, and the high-speed shaft. In conclusion, although the numerical simulation showed high contact stresses on the sun shaft teeth, the region with the unexpectedly nucleated crack was the tip of the tooth. The most likely factors that led to premature failure were the missed lubrication for the planetary bearings, a lack of cleanliness in regard to the raw materials of the gears (voids found), and problems with the sun shaft heat treatment. With the sun gear’s shaft, planet bearings, and planet gears broken into pieces, those small and large pieces dropped into the oil, between the gears, and into the tooth ring, causing the premature and catastrophic gearbox failure. Full article

The mobility and independence of people with disabilities could be significantly improved by wheelchairs. Wheelchair adoption is a complex process that is influenced by various factors, including personal demands, social dynamics, and technological advancements. To effectively promote wheelchair adoption and enhance the quality of life for people with mobility issues, it is crucial to understand the adoption of wheelchairs from a holistic perspective. A model comprising six hypotheses was developed based on the UTUAT-2 (Unified Theory of Acceptance and Use of Technology) framework with modifications. The data was analyzed from 330 individuals living with a disability using SPSS and Smart PLS. The study revealed that performance expectancy, effort expectancy, habit, social influence, and perceived infrastructure individually influence the intention to use wheelchairs. The results further revealed that price value and facilitating conditions were not significant predictors of intention to use a wheelchair. The results also showed that aesthetic design moderates the effect of effort expectancy, habit, social influence, price value, and perceived infrastructure on behavioral intention. Through a multidimensional lens, the paper offers practical recommendations to improve the adoption of wheelchairs for people with mobility impairments. Full article

The shift towards renewable energy, particularly wind energy, is rapidly advancing globally, with Southeastern Europe and Croatia, in particular, experiencing a notable increase in wind turbine construction. The frequent exposure of wind turbine blades to environmental stressors and operational forces requires regular inspections to identify defects, such as erosion, cracks, and lightning damage, in order to minimize maintenance costs and operational downtime. This study aims to develop a machine learning model using convolutional neural networks to simplify the defect detection process for wind turbine blades, enhancing the efficiency and accuracy of inspections conducted by drones. The model leverages transfer learning on the YOLOv7 architecture and is trained on a dataset of 231 images with 246 annotated defects across eight categories, achieving a mean average precision of 0.76 at an intersection over the union threshold of 0.5. This research not only presents a robust framework for automated defect detection but also proposes a methodological approach for future studies in deep learning for structural inspections, highlighting significant economic benefits and improvements in inspection quality and speed. Full article

A global motivation to reduce reliance on fossil fuels and transition to cleaner, renewable energy sources propels studies of innovative technologies to harness solar energy. This paper investigates the viability of a promising renewable energy technology, solar chimney power plants (SCPPs), in a domestic context. Using a scalable mathematical model, including thermodynamic processes within the collector, chimney, and turbine generator, the power output of SCPPs is assessed across five global locations with varying annual energy requirements: Aswan, Egypt, Cornwall, UK, Melbourne, Australia, Quito Ecuador, São Paulo Brazil. This research predicts a plant’s performance under differing plant geometries and meteorological inputs such as ambient temperature and solar irradiance, revealing that Aswan, Quito, and São Paulo can reliably produce year-round power, while Cornwall and Melbourne may need a supplementary energy supply in the winter months. The model establishes a linear relationship between collector radius and chimney height for each region to minimize geometry whilst fulfilling annual energy requirements, demonstrating that reducing one component size increases the other to maintain the required output. These geometries inform discussions of technology implementation, including the integration of an air-source heat pump (ASHP) to enhance performance, though it was found that the SCPP may not meet the power demand of the ASHP in Melbourne winter. Some lifecycle factors of the Melbourne and Quito plants are considered to assess the environmental viability of the technology. Full article