Search Results (828)

Modern logistics and manufacturing environments simultaneously demand mobility platforms that are compact enough to navigate narrow aisles and powerful enough to transport oversized or heavy components. We previously developed a compact Steering–Drive–Suspension (SDS) module that integrates steering, in-wheel drive, and suspension within a single wheel envelope, achieving $\pm {90}^{\circ }$ wide-angle steering with a single actuator. The present paper extends that hardware-centric work by treating the two-wheel (2WD) configuration assembled from two SDS modules as the unit module of the platform, building a four-wheel (4WD) operation by coupling two such 2WD units, and developing a unified balance and impedance-based control scheme. We derive a cart–pole inverted-pendulum model for the 2WD configuration and a planar 2-DOF bicycle model for the coupled and cooperative configurations, with full controllability proof and quantitative LQR robustness margins. Three Python 3.12 based scenarios validate the framework: (i) a 2WD inverted-pendulum tracking task, (ii) a forward and lateral relocation maneuver compared across SDS Crab, Ackermann, and four-wheel-steering modes, and (iii) cooperative transport of a $100\mathrm{kg}$ steel plate by two impedance-coupled 2WD units. Across all scenarios the proposed controllers achieve sub-centimetre tracking gap, pitch deviation within $\pm 2^{\circ }$, and well-damped cooperative behavior without payload sloshing. The results substantiate the central design claim that the SDS module’s compactness enables a single hardware platform to act simultaneously as an autonomous small-payload mover, a building block of a 4WD platform, and a cooperative agent for oversized loads. Full article

This study investigates the application of advanced metal additive manufacturing (AM) and topology optimization for the development of a structurally efficient and lightweight 3U nanosatellite frame. Payload weight is a critical factor in space mission costs; therefore, a stock 3U CubeSat design was subjected to structural optimization using specialized Generative Design Software. The optimized model was fabricated using Powder Bed Fusion—Direct Metal Laser Sintering (PBF-DMLS) on an EOS M290 metal printer with AlSi10Mg aluminum alloy. While AlSi10Mg differs in ultimate tensile strength from traditional wrought aerospace alloys, it was selected to evaluate the baseline feasibility of this application. To evaluate manufacturability and preliminary performance, Finite Element Analysis (FEA), including structural and modal response analyses, was conducted. While the optimized design successfully achieved a 53% mass reduction (from 333 g to 155 g) and met the 30 Hz minimum fundamental frequency requirement, static analysis indicated a maximum simulated stress of 287 MPa. Because this exceeds the material’s nominal yield strength of 220 MPa, localized plastic deformation is predicted in the bare-frame configuration under maximum launch loads. This necessitates further design iterations and full-assembly simulations, incorporating the load-sharing effects of integrated panels prior to physical qualification. Post-processing successfully met JAXA dimensional and surface roughness requirements. Ultimately, this study serves as a foundational manufacturability baseline, demonstrating the applicability of PBF-DMLS for nanosatellites. Full article

The increasing demand for sustainable and lightweight furniture systems has driven interest in additively manufactured polymer components as alternatives to conventional metal hardware. However, their performance at the functional assembly level under standardized loading conditions remains insufficiently explored. This study evaluates the feasibility of replacing metal drawer slides with fused deposition modeling (FDM)-based polymer alternatives fabricated from polylactic acid (PLA) and polyethylene terephthalate glycol (PETG). Unlike previous studies focused on material-level characterization, this work investigates fully functional drawer slide assemblies integrated into medium-density fiberboard (MDF) systems, enabling component-level assessment under realistic conditions. Specimens were designed in SolidWorks and fabricated under controlled printing parameters. Commercial metal slides were used as benchmarks. Mechanical performance was tested according to BS EN standards, and deformation was measured at multiple points. Statistical analysis included ANOVA, Tukey HSD, and t-tests at a 95% confidence level. Results showed significant differences among materials (p < 0.05). Metal slides exhibited the highest stiffness and minimal deformation. PLA showed stable performance with minor surface degradation, while PETG demonstrated lower dimensional stability and premature failure due to higher compliance. Overall, PLA-based FDM components offer a cost-effective alternative for non-heavy-duty applications, whereas PETG requires further optimization. The study bridges additive manufacturing and real-world furniture component performance under standardized testing. Full article

The end-to-end design and successful integration of a low-voltage educational electric vehicle (EV) built around a Controller Area Network (CAN) backbone is presented in this study. Its reproducible system architecture was built on a unified message specification database, and a set of bring-up and diagnostic procedures enables students to assemble, validate, and extend an EV using commodity controllers. The vehicle was manufactured and commissioned with classic-CAN operating at 250–500 kbps, integrating traction, battery management system, dashboard, lighting, and safety nodes. Initial tests confirmed reliable messaging and error-free operation under typical campus driving conditions. In addition, an upgrade path to CAN with flexible data-rate and 100BASE-T1 Ethernet is provided for future curricula. The platform reduces integration complexity, shortens fault-finding, and supports multidisciplinary teaching across mechanical engineering, electrical and computer engineering, and computer science. Full article

The rapid growth of artificial intelligence (AI) workloads is reshaping semiconductor design across architecture, interconnect, memory hierarchy, packaging, timing, and design automation. Rather than converging on a single hardware solution, the field is expanding into a heterogeneous ecosystem that includes data-center graphics processing units (GPUs), edge neural processing units (NPUs), and application-specific integrated circuits (ASICs), field-programmable gate array (FPGA)-based and hybrid AI system-on-chip (SoC) platforms, chiplet-enabled systems, and emerging beyond-conventional-silicon approaches such as photonic, neuromorphic, and analog in-memory processors. This paper presents a comprehensive review of AI-on-chip systems from a cross-layer perspective. It examines AI chip architectures and hardware platforms, network-on-chip (NoC) designs for AI communication patterns, and algorithm–hardware co-design methods for model acceleration, including compression, quantization, and sparsity-aware optimization. It also reviews clocking, synchronization, and clock-domain-crossing (CDC) challenges in large heterogeneous systems and chiplets, as well as manufacturing, advanced packaging, and reliability issues, including two-and-a-half-dimensional (2.5D) and three-dimensional (3D) integration, thermal and mechanical constraints, assembly quality, and long-term yield considerations. In parallel, the paper surveys the growing role of AI in chip design itself, covering machine-learning-assisted analysis, Bayesian and reinforcement-learning-based optimization, and the emerging use of large language models (LLMs) and AI agents for register-transfer level (RTL) generation, design-space exploration, and autonomous electronic design automation (EDA) workflows. Finally, it discusses beyond-silicon AI chip directions and the broader economic and industry context shaping cloud, on-premises, and edge deployment. By integrating these topics into a unified framework, this review highlights the key technological drivers, system-level tradeoffs, and future research directions that will define next-generation scalable, reliable, and energy-efficient AI-on-chip systems. Full article

Accurate detection and reliable grasping of small bolts are essential for intelligent manufacturing and automated assembly. However, this remains a challenge due to the small size, slender geometry, and metallic reflective surfaces of bolts. In this paper, we propose a vision-guided robotic bolt handling framework that integrates lightweight object detection, optimization-oriented grasp execution, and collision-aware trajectory planning. The lightweight YOLOv8n-BoltLite detector, improved with E-C2f, LCA, SA-PAN, and WD-IoU loss, enhances localization accuracy and feature representation for small and slender bolts. A robotic grasping framework is designed to transform detection results into executable robotic actions through 3D pose estimation, mid-shank grasp point generation, and optimization-oriented execution formulation. Additionally, a five-segment trajectory planning strategy ensures safe and efficient robot motion. Experimental results show that YOLOv8n-BoltLite achieves a five-run average mAP of 99.64 ± 0.05% with 198 FPS, and 3.02 M parameters. On an additional challenging external test set involving illumination variation, clutter, partial occlusion, reflection, and clustered bolts, the proposed detector achieves 94.62 ± 0.18%, outperforming recent lightweight detectors under the same training protocol. Robotic experiments involving 1000 controlled grasping trials and 300 multi-target grasping attempts demonstrate a controlled-condition success rate of 97.0% and improved target-selection reliability in multi-bolt scenes. These results suggest that the proposed framework offers a practical and efficient solution for automated bolt handling in intelligent manufacturing environments. Full article

A complex curved reflector made from a 40% silicon–aluminum alloy (AlSi40) can meet the requirements of optical systems operating across the infrared, near-infrared, and visible bands. It enables an athermalization design with simplified alignment and assembly, while offering high manufacturing efficiency and low costs. This makes it ideal for widespread use in high-end optical systems. As an enabling technology for the fabrication of AlSi40 freeform mirrors, error compensation in ultra-precision (UP) diamond turning is currently a research hotspot; however, current error compensation methods still have considerable room for improvement in terms of both accuracy and manufacturing efficiency. To address this issue, this study proposes an efficient and highly accurate method: a polar grid is defined in the machining coordinate system, and the corresponding surface point cloud is calculated. Using measured point clouds from reference spheres and freeform form error in the measurement coordinate system, mounting pose errors and form error with measurement error removed are determined via least squares. Machining error at grid points is then calculated via coordinate transformations and bicubic spline interpolation, and applied to correct cutter contact points (CCPs). Cutter location points (CLPs) are finally obtained using piecewise cubic spline fitting and a bisection method. With this method, average form error of four AlSi40 substrates improved from RMS 114.8 nm to 47.9 nm, and for four AlSi40 substrates with nickel–phosphorus (NiP)-plated surfaces, from RMS 71.3 nm to 31.1 nm. The compensated accuracy meets near-infrared stellar tracker requirements without polishing, greatly enhancing freeform mirror manufacturing efficiency. Full article

Building Information Modelling (BIM) workflows for prefabricated construction lack mechanisms that generate and compare alternative component configurations directly from a design model. Existing approaches define the optimisation search space manually and outside the model, address only one or two criteria, and treat the Work Breakdown Structure (WBS) as a post-design planning tool. This paper reinterprets the WBS as a generative decomposition mechanism. A WBS Engine decomposes the geometry of an existing BIM model into prefabricated subsystems before design decisions are fixed, producing the search space for optimisation without manual parametrisation. A Scenario Evaluator queries a database of 47 prefabricated components, and NSGA-II evaluates 60 configurations against four objectives. These are total cost, embodied carbon, assembly factor and number of lorry trips. Applied to a residential case study implemented in Dynamo, the prototype identified 16 non-dominated solutions. The best compromise configuration achieved a total cost of £150,444.01, 127,731.00 kgCO₂e, an assembly factor of 0.190 and 10 lorry trips. Wall module size accounted for 17.4% of cost variation, while floor module size governed assembly complexity. The findings show that BIM-WBS integration with multi-objective optimisation supports informed early-stage decisions in industrialised construction. Full article

Cutaneous infections and chronic inflammatory wounds remain difficult to treat because antimicrobial resistance, polymicrobial biofilms, excessive protease activity, oxidative stress, and impaired barrier repair collectively reduce the effectiveness of conventional topical therapies. Plant-derived antimicrobial peptides (AMPs) and peptide-associated bioactives offer antimicrobial, antibiofilm, immunomodulatory, and tissue reparative potential; however, their clinical translation is limited by proteolytic instability, poor stratum corneum penetration, short cutaneous residence time, formulation variability, cytotoxicity risks and limited human evidence. The key research gap is the lack of an integrated translational framework linking plant-derived peptide bioactivity with polymer engineering, advanced delivery systems, skin microenvironment biology, manufacturability, and regulatory feasibility. This review aims to critically evaluate the design principles, therapeutic mechanisms, delivery platforms, and translational barriers of plant-based peptide–polymer therapeutics for cutaneous infection and inflammation. We summarize major classes of plant-derived antimicrobial peptides, including defensins, cyclotides, thionins, hevein-like peptides, snakins, lipid transfer proteins, and knottin-type scaffolds, and examine engineering strategies such as self-assembly, aromatic N-capping, PEGylation, lipidation, dendritic architectures, and stimuli-responsive conjugation. We further discuss topical matrices, nanocarriers, liposomes, electrospun fibers, and surface-tethered biomaterials as delivery platforms for improving peptide stability, local retention, and controlled release. Finally, we identify key translational bottlenecks, including selectivity, toxicity, scalability, batch reproducibility, regulatory classification, and insufficient clinical validation. Mechanism-driven peptide optimization, quality-by-design manufacturing, standardized preclinical models, and controlled clinical trials will be essential for advancing these systems toward safe and effective dermatological therapies. Full article

This study investigates the energy absorption capacity of large three-honeycomb cell cores of different geometrical configurations, focusing on the influence of the constructive parameters on their impact response. The analyzed sandwich structures were additively manufactured using Onyx (a nylon-based composite) for the core cells and integrated into an assembly consisting of 6060-aluminum face sheets and encapsulated within a 6060-aluminum tube. These configurations represent a realistic engineering solution for lightweight structures designed for energy absorption. The analyses were conducted for two impact energy levels, 20 J and 50 J, enabling the evaluation of the structural sensitivity to different dynamic loading conditions. The results indicate a significant reduction in peak force with an increasing number of cells along the height. Compared to the single-cell configuration, the peak force decreases by approximately 15% for the two-cell configuration and 22.5% for the three-cell configuration, corresponding to a reduction of roughly 9% between the two- and three-cell cases. These findings highlight the critical role of geometry in optimizing the impact performance of honeycomb structures and provide relevant insights for the design of additively manufactured energy-absorbing crush-type components in engineering applications. Full article

Conventional formwork systems are limited in their ability to efficiently realize complex and free-form concrete geometries, while additive manufacturing (AM)-based formwork faces constraints in casting-stage structural stability and cost-effectiveness, particularly at construction scale. To address these limitations, a hybrid formwork system integrating a structural steel frame with 3D-printed modules is proposed, in which the steel frame resists casting-induced lateral pressure while the printed components define complex mold geometries. The system was fabricated and validated through a full-scale case study structure measuring 3.0 m × 1.7 m × 2.2 m, produced using a large-scale fused deposition modeling (FDM) process with carbon-fiber-reinforced ABS (ABS-CF20). Geometric accuracy was evaluated by comparing design dimensions with as-built measurements across planar, edge, curved, and inclined regions. Construction efficiency and cost performance were assessed through process-based and cost-based comparisons with conventional steel formwork and fully 3D-printed formwork alternatives. The constructed structure reproduced the intended geometry with an average deviation of approximately 3.2 mm and a maximum deviation within ±4 mm, and no notable formwork deformation or damage was observed during concrete casting. Relative to conventional steel formwork, the hybrid system reduced total fabrication duration by about 50% and fabrication cost by about 60% based on a normalized cost index, while also outperforming fully 3D-printed formwork in cost efficiency by about 45%. The modular configuration and bolted connection system further improved transportability, on-site assembly efficiency, and component reusability. These findings demonstrate that the proposed hybrid formwork system provides a practical and resource-efficient pathway for fabricating complex concrete structures, supporting the broader adoption of digital fabrication in sustainable construction practice. Full article

Purpose: To develop an accelerator neutron source suitable for boron neutron capture therapy—a new promising method for treating malignant tumors—and to develop dosimetry tools and methods. Methods: Research into the transport and acceleration of a beam of charged particles, development and manufacture of an accelerator neutron source, study of the radiation generated, and development and implementation of dosimetry tools and methods. Results: A facility called VITA has been created, which includes a tandem electrostatic accelerator of an original design for producing a 2.3 MeV 10 mA proton beam, a lithium target for generating neutrons in the ⁷Li(p,n)⁷Be reaction, and a beam shaping assembly for forming a therapeutic neutron beam. The facility at the institute is used for scientific research, the facility in Xiamen (China) is used for clinical trials, and the facility in Moscow (Russia) will soon be used for clinical trials. Also, new tools and methods for measuring the boron dose, γ-ray dose, and sum of the fast neutron dose and the nitrogen dose have been proposed and implemented. The conducted studies demonstrated the high efficiency of the VITA^® facility, the first possibility of implementing prompt γ-ray spectroscopy for boron imaging, and the first possibility of implementing lithium neutron capture therapy, which has advantages over BNCT, and also presented the results of the development of new tools and methods for measuring the boron dose, γ-ray dose, and the sum of the fast neutron dose and the nitrogen dose. Conclusions: The authors strongly recommend using prompt γ-ray spectroscopy in treatment and developing lithium neutron capture therapy, including in combination with BNCT, and note the high efficiency, reliability and compactness of the VITA^® facility. Full article

At present, although there are many SCARA manipulator solutions with vertical lifting functionality, they generally suffer from high maintenance costs and complex structures. Moreover, systematic performance evaluations based on international standards are lacking, leading to unclear critical performance boundaries such as accuracy and payload in practical applications. To address these issues, this paper designs and manufactures a low-cost SCARA manipulator for educational and research demonstrations as well as light-duty electronic parts assembly scenarios. A “leadscrew + stepper motor” scheme is adopted for vertical lifting, and an Arduino Mega 2560 development board serves as the core controller, significantly reducing system cost. A three-dimensional model is established using SolidWorks 2022, and kinematic simulations are carried out with MATLAB 2024a to preliminarily verify the feasibility of the mechanism. Subsequently, a physical prototype is built and experimental tests are conducted in accordance with the ISO 9283 standard. The experimental results show that the repeatability of the manipulator is controlled within the range of 0.05–0.3 mm, the path deviation caused by vibration lies between −0.52 mm and 0.3 mm, and the maximum payload capacity is 3.91 N. These experimental data can serve as a benchmark for the design and performance comparison of similar low-cost manipulators. Full article

This paper presents a practical implementation of a 3D-printed spherical Luneburg lens for gain enhancement of a WR-28 open-ended waveguide antenna operating in the Ka-band. The lens is designed based on Luneburg theory and realized using a six-zone discretized gradient-index structure, providing a balance between theoretical performance and fabrication feasibility. The proposed design enables the realization of the required permittivity distribution using a single dielectric material, where the effective permittivity of each zone is controlled through infill variation in a fused deposition modeling (FDM) process. To facilitate fabrication, the lens is divided into two hemispherical parts, enabling reliable manufacturing and assembly while maintaining the intended dielectric profile. The antenna performance is experimentally evaluated through reflection coefficient (S₁₁) measurements and radiation pattern characterization in both the XZ and YZ planes over the frequency range of 26.5–40 GHz, including co-polarized and cross-polarized responses. The proposed antenna achieves a simulated realized gain ranging from 17.6 dBi to 19.83 dBi, while the measured realized gain ranges from 16.42 dBi to 18.43 dBi, with a maximum deviation of 1.47 dB. In comparison, the standalone WR-28 open-ended waveguide exhibits a measured realized gain of 7.22–8.01 dBi. The integration of the six-zone Luneburg lens results in a realized gain enhancement of 9.20–10.97 dB across the operating band. These results confirm that the proposed approach provides a simple, low-cost, and experimentally validated solution for high-gain millimeter-wave antenna applications, while maintaining good agreement between simulation and measurement. Full article

Rod ends are critical structural components primarily designed to sustain axial loads in mechanical and aeronautical assemblies. However, operational conditions may involve transverse loading, which induces significant bending stresses concentrated in the threaded shank region. This research presents an experimental investigation aimed at characterizing the elastoplastic bending behavior of the threaded portion of rod ends subjected to such off-axis loads. Specimens manufactured from precipitation-hardened stainless steel 17-4 PH were tested under both displacement and force control strategies. Each specimen was subjected to incremental loading until failure to determine the elastic limit, yield point, ultimate bending strength and fracture mode. The experimental results enabled a preliminary assessment of the static resistance of the threaded region; furthermore, a comparison with analytical formulations and empirical estimation methods available in the literature revealed promising agreement. These findings highlight the importance of accounting for non-axial loading in the design of threaded joints for critical applications. This study establishes a baseline for broader experimental campaigns aimed at validating these results and exploring fatigue behavior under cyclic transverse loads. Full article