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Neural-network-based incremental backstepping sliding mode control for flying-wing aircraft
Get PDFThe nonlinear trajectory tracking control problem is studied for a flying-wing aircraft. Starting from a nonlinear dynamics model of the flying-wing aircraft, the trajectory tracking control is decomposed into multiple loops of position control, flight path control, and attitude control. An incremental backstepping sliding mode control is proposed to implement attitude control, while an incremental nonlinear dynamic inversion and a nonlinear dynamic inversion design are used to deal with the nonlinear system model for the flight path and position control, respectively. In addition, a radial basis function neural-network-based extended state disturbance observer is proposed to deal with model uncertainties, gust disturbances, and unknown faults of the aircraft. The closed-loop control system is proved to be stable using Lyapunov theory. The performance of the proposed disturbance-observer-based incremental backstepping sliding mode control is demonstrated in simulation through a set of three-dimensional tracking scenarios. Compared with both backstepping control and backstepping sliding mode control, tracking performance measured by settling time, tracking error, and overshoot are improved by the proposed design when realistic trajectory tracking missions are executed.The work described in this paper was supported by National Natural Science Foundation of China (52272400, 10577012).Journal of Guidance, Control, and Dynamic
Sedimentation of inclusions in melts of aerospace structural aluminium alloy castings: a sustainable approach
Get PDFAchieving the full potential of mechanical and other properties in aerospace structural aluminium alloy castings is often hindered by the presence of detrimental inclusions in the melt during casting. The inclusions arise from high-temperature chemical reactions and the dissolution of substances in contact with the melt or pre-existing in the alloy. Suitable additions to the melt can precipitate on the inclusions and cause them to sediment, resulting in cleaner melt. Simulation techniques were employed with commercial software packages (Flow3D) using high-performance cluster computing (HPC) facilities to analyse the behaviour of impurity particles of various sizes and distributions under different boundary conditions such as temperature, pressure, flow rate, and heat transfer. The simulations provide insights into the sedimentation process to identify effective methods for eliminating/reducing these particles from the melt. Some of the practical melt holding or processing challenges, and mitigations, are also discussed.The financial support from UK Research and Innovation through the Ultra Clean CAST Digital Manufacturing project is gratefully acknowledged.Light Metals 2025. TMS 202
Comparative analysis of touchscreen inceptors and traditional sidesticks on flight decks: flight performance, visual behaviours and situation awareness
Get PDFThe concept of touchscreen primary control device is a novel approach of touchcreen implentation. The objective of this study is to investigate differences in flight performance and attention allocation between a touchscreen inceptor and a traditional sidestick. Twenty-one participants flew four simulated instrument landing system (ILS) approaches - with the touchscreen inceptor or traditional sidestick - during flight scenarios where an aircraft attitude disturbance was either present or absent. Results demonstrated that participant performance scores were worse with the touchscreen inceptor compared to the sidestick during attitude disturbance scenarios. Interestingly, participants exhibited reduced attention to external visual cues with the touchscreen inceptor compared to the sidestick. In addition, use of the touchscreen inceptor resulted in lower performance and lower self-reported situation awareness. Overall, the touchscreen inceptor demonstrated poorer performance compared to the traditional sidestick, highlighting limitations in its current design that warrant cautious consideration and further investigation.European CommissionThis research is co-financed by the European Union through the European Social Fund (grant number POWR.03.02.00–00-I029).Ergonomic
Guest editorial: transforming food supply chains: harnessing the potential of the digital era
Get PDFThe International Journal of Logistics Managemen
Securing UAV flying ad hoc wireless networks: authentication development for robust communications
Get PDFUnmanned Aerial Vehicles (UAVs) have revolutionized numerous domains by introducing exceptional capabilities and efficiencies. As UAVs become increasingly integrated into critical operations, ensuring the security of their communication channels emerges as a paramount concern. This paper investigates the importance of safeguarding UAV communication against cyber threats, considering both intra-UAV and UAV–ground station interactions in the scope of the Flying Ad Hoc Networks (FANETs). To leverage the advancements in security methodologies, particularly focusing on Physical Unclonable Functions (PUFs), this paper proposes a novel authentication framework tailored for UAV networking systems. Investigating the existing literature, we categorize related studies into authentication strategies, illuminating the evolving landscape of UAV security. The proposed framework demonstrated a high level of security with lower communication and computation costs in comparison with selected studies with similar types of attacks. This paper highlights the urgent need for strong security measures to mitigate the increasing threats that UAVs encounter and ensure their sustained effectiveness in a variety of applications. The results indicate that the proposed protocol is sufficiently secure and, in terms of communication cost, achieves an 18% improvement compared to the best protocol in the referenced studies.Sensor
Vitacrystallography: appearance and development of cancer-induced structural biomarkers in a mouse model
Get PDFStructural biomarkers determined by X-ray scattering of the tissues can complement conventional diagnostics and provide a pathway for early detection of diseases. In the present study, mouse models were utilized to observe the progression of prostate cancer. We induced cancer in the left lobe of the mouse prostate, whilst the right lobe was left uninoculated. The mice were sacrificed at increasing systematic time points, and lobe samples were subsequently analyzed using X-ray scattering. Control samples were also collected from healthy mice sacrificed at the same time points. This investigation revealed that the ratio between the X-ray scattering peaks associated with the lipids and water can serve as a structural biomarker of cancer, and this biomarker develops as the tumor advances. The obtained cancer trajectory can serve as a baseline for the determination of the disease stage, and the biomarker movement along the trajectory can be evidence of the healing or disease progression.This research was funded by Innovate UK, part of UK Research and Innovation, through the Smart Grant scheme (Grant number 10063925).Lif
Pioneering microsphere-dope dyeing for sustainable cellulosic fibre colouring
Get PDFThe textile industry has long been criticised for its high energy consumption, significant pollution, and low efficiency, highlighting the urgent need for sustainable innovations. This study presents an advanced approach to fabric dyeing by integrating microencapsulation with dope dyeing to enhance indigo retention in cellulose fibres. Encapsulating indigo within alginate-based microspheres prevents unwanted chemical reactions and minimises environmental impact. Microscopic and SEM analyses confirm the successful incorporation of indigo within fibres, significantly reducing dye loss (0.11-0.18 %) compared to traditional methods. Eliminating the need for reducing agents and oxidants simplifies wastewater treatment, while the fibres exhibit enhanced mechanical properties and exceptional wash durability, retaining 99.76-99.95 % of their weight after 20 cycles-comparable to pure cellulose fibres. A 48-h washing test further demonstrates excellent colour fixation, with minimal indigo detected in the washing solution (0.0042-0.0053 mg/L). By significantly reducing dye loss and chemical usage, this method offers a promising solution to minimising the environmental footprint of textile dyeing, particularly in cellulosic fibre applications. These findings highlight microsphere-assisted dope dyeing as a viable, sustainable alternative to conventional techniques, aligning with global sustainability goals while maintaining high-quality fibre production.International Journal of Biological Macromolecule
Use of non-intrusive flow diagnostics for aero-engine inlet flow distortion measurements in an industrial wind-tunnel
Get PDFIn crosswind conditions, aero-engine intakes experience unsteady flow distortions at the fan face, typically caused by the ingestion of ground vortices and flow separation. These distortions can negatively impact both intake performance and the compatibility of the downstream propulsion system. Understanding the aerodynamics of these flows is crucial for developing next-generation aircrafts with propulsion systems integrated more closely with the airframe. Optical measurement techniques provide detailed datasets in both space and time to support this understanding, but several challenges limit their widespread use in propulsion integration testing. This study demonstrates a novel application of non-intrusive flow diagnostics in an industrial setting for propulsion integration testing. Optical measurements were conducted within an aspirated intake configuration and, later, within a fully coupled fan-intake propulsion system representative of a modern high-bypass aero-engine. Several innovative solutions were developed to improve the integration of optical systems into industrial settings and enhance data acquisition efficiency. The analysis of the results yielded significant contributions about the unsteady interactions within civil intakes at crosswind and high incidence conditions, which are expected to have a notable impact on the development of future, closely integrated propulsion systems architectures able to meet the specified NetZero targets.The work presented herein was conducted under the NIFTI project which received funding from the Clean Sky 2 Joint Undertaking (JU) under Grant Agreement No 866521AIAA SCITECH 2025 Foru
Integrating sustainability across the lifecycle of electric vehicle batteries: circular supply chain challenges, innovations, and global policy impacts
Get PDFCorrigendum published for this paper at https://doi.org/10.1016/j.rser.2025.115894This study investigates the integration of sustainability practices into the circular supply chain (SC) of electric vehicle (EV) batteries to address environmental and economic challenges. Using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) protocol, a systematic review of 147 articles (2009–2024) identifies key challenges, solutions, innovations, and policy measures shaping the EV battery SC. The research uncovers 10 major challenges, 31 sub-challenges, and 160 detailed challenges, highlighting issues related to SC resilience, environmental impact, and economic sustainability. In response, 40 main solutions and 174 complete solutions are mapped, leading to the identification of 102 detailed technologies, 24 sub-technologies, and 8 core technologies supporting circular economy principles. These technologies are analysed for their long-term industry impact, with comparisons within categories to highlight their advantages, disadvantages, and contributions to circular economy goals. Additionally, global policy analysis reveals regulatory advancements, with China and the UK leading efforts to improve recycling, material recovery, and sustainability governance. This study also compares EV battery policies across countries using indicators like policy coverage, enforcement intensity, and effectiveness, highlighting their impact on sustainability and resource efficiency. A conceptual framework is developed to integrate these challenges, solutions, and innovations into a sustainable EV battery SC. The study concludes with theoretical insights, industry recommendations, and policy implications, offering a structured pathway toward sustainable and resilient EV battery SCs.Renewable and Sustainable Energy Review
Robust aeronautical communications enabled by UAV operations and LEO satellites
Get PDFIn the realm of modern aerospace communications, the integration of Unmanned Aerial Vehicles (UAVs) with Low Earth Orbit (LEO) satellite constellations can offer a transformative solution for enabling Beyond Visual Line of Sight (BVLOS) operations. Due to initial safety operation demand of UAV BVLOS communication new metrics, this paper proposes a new quality of service (QoS) framework for uplink communication between IRIDIUM satellite constellation and UAV. The objective is to benchmark key QoS metrics for UAVLEO communications using a Non-Terrestrial Network (NTN) narrowband (NB) channel. However, this study performs metrics such as latency and throughput across various elevation angles and environments. Different sample rates are evaluated to assess their impact on communication performance. Simulation analysis indicate that lower sample rates provide reduced latency and stable throughput suitable for telemetry, while higher sample rates increase throughput at the cost of higher latency. This study can be a road map for QoS metrics for optimizing satellite communication systems in UAV operations and demonstrates optimal communication for BVLOS missions in rural, suburban and underserved areas where ground infrastructure is limited. The findings are compared against current standards and regulatory benchmarks for validation.2025 Integrated Communications, Navigation and Surveillance Conference (ICNS