Search Results (99)

Tilt-to-length (TTL) coupling is a critical noise source in high-precision interferometric measurements, particularly in systems involving angular actuation and beam steering. This paper proposes a nonlinear cyclic modulation method to identify lateral misalignment and suppress the associated TTL coupling. By applying controlled sinusoidal angular excitation and evaluating the complex modulus ratio between the optical path difference (OPD) and the beam angle at the modulation frequency, the TTL noise induced by the point-ahead angle mechanism (PAAM) is separated and quantified in the frequency domain. Experimental results demonstrate that lateral offset correction reduces TTL noise by 94%, corresponding to a suppression factor of 15.5 and enabling pointing control better than 21 µm/rad. Meanwhile, the parasitic displacement noise of the PAAM is reduced from 10 pm/Hz^1/2 to below 4 pm/Hz^1/2. These results validate the effectiveness of the proposed modulation-based identification framework and demonstrate its applicability to precision interferometric systems. Full article

Integrating renewable energy harvesting with wireless power transfer (WPT) introduces complex multi-physics coupling challenges, primarily regarding thermal detuning and conversion inefficiencies within compact enclosures. This study proposes an optimized architecture and analytical framework for a Solar-Driven Portable Energy Storage System (SPESS) that bridges the gap between solar harvesting and autonomous wireless delivery. The system integrates a high-efficiency 5 V monocrystalline photovoltaic (PV) array with a 10,000 mAh lithium-ion core, regulated by an adaptive Maximum Power Point Tracking (MPPT) algorithm. We formalize the synergistic coupling between thermal and electrical subsystems, demonstrating how iterative thermal–electric co-design—utilizing CFD-modeled ventilation and anisotropic graphite spreaders—effectively suppresses capacitive drift in the resonant network. Unlike fixed-frequency chargers, this design employs Phase-Locked Loop (PLL) frequency stabilization to maintain a “High-Q” state, achieving wireless transmission efficiencies exceeding 85% and a measured 12.3% restorative gain in the WPT stage compared to a thermally detuned baseline. Robustness analysis confirms spatial resilience up to 10 mm of lateral misalignment and thermal stabilization at 48 °C under continuous 15 W load, contributing to a calculated 18% extension in battery cycle life via suppressed chemical degradation. Experimental validation across varying irradiance levels (100–1200 W/m²) demonstrates a full recovery cycle of 23.6 cumulative solar hours at Standard Test Conditions (STC). This research provides a scalable, theoretically grounded framework for resilient, self-sustaining energy modules for disaster relief, remote education, and mobile health applications. Full article

Background: Open banking (OB) is rapidly transforming financial ecosystems by enabling controlled data sharing among multiple actors through application programming interfaces (APIs). While this transformation promises innovation and competition, it also introduces complex security challenges that extend beyond purely technical considerations. Despite growing attention in academic and professional domains, existing reviews provide limited integration of security concerns with global adoption patterns and cross regional variation. Methods: This systematic review analyses empirical and conceptual research on security in OB published between 1999 and 2025, capturing early digital banking studies that later informed the development of OB. The literature is structured into three distinct phases: foundational digital banking developments, regulatory formalisation of OB frameworks, and post-implementation expansion of OB ecosystems. A comprehensive search was conducted across major academic databases and scholarly portals, complemented by relevant regulatory and policy sources. Following duplicate removal, title and abstract screening, full-text eligibility assessment, and methodological quality appraisal, 117 studies were retained for qualitative synthesis. Results: The findings reveal recurring security challenges arising from the interaction between technological infrastructures, regulatory frameworks, and user behaviour within OB ecosystems. Technical safeguards such as APIs, strong customer authentication, and encryption are necessary but insufficient when they are misaligned with regulatory implementation and user behaviour. Behavioural factors, including trust, consent understanding, and security-related decision making, play a central role in shaping ecosystem resilience. Based on this synthesis, the study develops a tri-dimensional security framework integrating technological, regulatory, and behavioural dimensions. The bibliometric analysis of 117 studies reveals that technological security dominates the literature (58%), followed by regulatory governance (44%) and behavioural dimensions (42%). However, only 17.9% of studies integrate all three dimensions simultaneously. APIs and authentication mechanisms represent the most frequent technological terms, while PSD2 and GDPR dominate regulatory discourse. Trust and decision-making are the most recurrent behavioural constructs. The relatively low proportion of fully integrated studies confirms a structural fragmentation within OB security research, thereby empirically justifying the proposed tri-dimensional framework. Chronologically, early studies (1999–2015) predominantly focused on technical security mechanisms and regulatory compliance, whereas more recent research (2020–2025) increasingly highlights the interplay between regulatory frameworks and user behaviour, suggesting a shift towards a more holistic understanding of security within OB adoption. Conclusions: This systematic review concludes that integrating technological, regulatory, and behavioural perspectives advances a more comprehensive understanding of security in OB ecosystems. The proposed tri-dimensional security framework provides a structured foundation for future research and supports policy-relevant and practice-oriented security design. Full article

Scoliosis is a three-dimensional spinal deformity that may affect musculoskeletal alignment, respiratory mechanics, and neuromotor control. Rigid thoraco-lumbo-sacral orthoses (TLSOs) remain the primary conservative treatment during skeletal growth. Most brace systems rely on three-point pressure mechanisms that primarily generate lateral compression forces, while the contribution of shear components to corrective biomechanics has been insufficiently quantified. This study presents the experimental and analytical validation of the Canali Front-Push Orthopedic Brace, a rigid orthotic system designed to generate controlled compressive and shear forces through a frontal thrust mechanism and anterior rib cage engagement. By applying anterior force, the device reduces the frontal-plane lever arm, thereby limiting the mechanical moment that contributes to transverse plane rotation. An instrumented four-segment torso model derived from the internal CAD geometry of the brace was developed to independently measure upper compression, lower compression, and intersegmental shear forces. Controlled misalignment conditions (0 mm, 2 mm, and 4 mm) were introduced to simulate asymmetric engagement of the orthosis. Three load cell configurations (200 N and 500 N capacity) were tested. Mechanical endurance of the rack–latch fastening system was also evaluated. A predictive shear–misalignment relationship was derived and experimentally validated. Peak compressive forces reached approximately 370 N, while shear forces increased from less than 40 N under symmetric alignment (D0) to approximately 170 N under maximal misalignment (D4). Shear activation demonstrated near-linear proportionality to imposed geometric asymmetry (R² > 0.94). Following cyclic loading, the fastening system stabilized mechanically around 300 N. Measurement repeatability showed a coefficient of variation below 5%. These findings demonstrate that the brace produces predictable and controllable shear activation while maintaining high mechanical repeatability. The results provide a quantitative biomechanical framework for understanding shear-induced corrective mechanics in scoliosis bracing and support future studies integrating computational modeling and clinical validation. The proposed mechanical framework may contribute to the development of next-generation orthotic strategies aimed at controlling spinal rotation through vector modulation rather than purely compressive correction. Full article

Background: Achondroplasia, the most common genetic dwarfism caused by the FGFR3 mutation (autosomal dominant, 80% de novo), results in a disproportionately short stature. Thoracolumbar kyphosis (TLK), combined with characteristic spinal canal stenosis, increases the risk of symptomatic compression, yet the literature lacks clear thresholds for symptom onset or progressive deformity angles. Methods: A 16-year-old female with achondroplasia presented with rapidly progressive kyphosis despite conservative management (bracing and therapy). Over six months, she developed neurogenic claudication; bilateral leg pain; weakness; and paresthesia that worsened with standing/walking, which was relieved by flexion/sitting. Imaging demonstrated surgical-threshold kyphosis with progressive spinal misalignment. Her symptoms indicated compressive myeloradiculopathy from lumbar stenosis, critical given achondroplasia’s congenitally narrowed canal and heightened neurologic vulnerability. Results: Staged surgery planned: Posterior fusion T6-L4 with pedicle screws and then extensive decompression (laminectomy/foraminotomy T11-L3), L1 corpectomy with expandable titanium cage, and Ponte osteotomies. Intraoperative complications included a malpositioned left T10 screw breaching the anterior/lateral cortex near the aorta, requiring urgent revision. Postoperatively: Neurogenic bladder, wound leakage, and E. coli urinary tract infection (UTI) with fever (treated with IV antibiotics). After infection resolution, definitive surgery removed the malpositioned screw and completed decompression, corpectomy, cage placement, bone grafting, and osteotomies, successfully resolving neurological symptoms. However, 13 cm trunk lengthening caused severe functional impairment—disproportionately short arms prevented independent toileting and dressing. Left arm lengthening via external fixation restored partial function. At 2.5-year follow-up, there was solid fusion, no neurological deficits, and improved quality of life. Conclusions: Surgery addresses severe TLK, vertebral wedging, and neurogenic claudication in achondroplasia. Vertebral column resection effectively corrects TLK and neurological deficits but carries a high complication risk. This should be reserved for severe TLK with hypoplastic vertebrae, performed by experienced surgeons. Critically, correction magnitude must preserve limb–trunk proportions to prevent functional disability, as excessive lengthening may necessitate additional limb procedures for independence restoration. Full article

To address the issue of significantly reduced coupling coefficient and limited transmission efficiency in traditional flat solenoid magnetic couplers within wireless power transfer (WPT) systems under horizontal lateral offset conditions, this paper proposes a design method for a concave flat solenoid coil magnetic coupler for engineering applications, aiming to achieve high misalignment tolerance. An equivalent model of the LCC/S compensation circuit is established, its output characteristics are analyzed, and the parameter configuration method for its resonant elements is derived. Secondly, from the perspective of winding arrangement, the mechanism by which the coil winding method, turn spacing, and port concavity angle affect the uniformity of magnetic field distribution and the retention rate of the coupling coefficient is analyzed in detail, and corresponding parameter trade-off and optimization methods are proposed. Subsequently, a simulation model of multiple configuration magnetic couplers is established based on Ansys/Maxwell, comparing the magnetic field distribution and coupling coefficient variation of different structures under horizontal offset conditions. The results show that the concave structure with a non-uniform arrangement and a port concavity angle of 30° can still maintain a high coupling coefficient and stable transmission performance under a maximum horizontal offset equal to 60% of the corresponding transmitter-side characteristic dimension. To achieve lightweight and integrated design, the receiver is designed with a flexible printed circuit board (FPC) coil structure, meeting the miniaturization and high power density requirements of low-to-medium power portable devices. Finally, a 100 W experimental prototype was built. Experimental results show that within an offset range of ±15 mm on the X-axis and ±30 mm on the Y-axis at the receiver, the system output voltage fluctuation is controlled within 4%, and the maximum transmission efficiency reaches 87.3%. These results verify the feasibility and practical applicability of the proposed magnetic coupler with high misalignment tolerance. Full article

The widespread commercialization of wireless chargers for electric vehicles generally suffers from one main problem, which is the perfect alignment between the two coils, leading to a decrease in mutual inductance, which causes a drop in magnetic coupling and even a failure to transfer power. To address this persistent problem, this work proposes a comprehensive and integrated method for optimizing the coils and control architecture for reliable and safe battery charging. To address the challenges of a complex, nonlinear design space and the need for misalignment-tolerant geometries, we employ a memetic algorithm (MA) that hybridizes Particle Swarm Optimization (PSO) for broad global exploration with Mesh Adaptive Direct Search (MADS) for precise local refinement. This combination effectively avoids poor local solutions—a limitation of standalone PSO or GA approaches reported in recent studies—while efficiently converging to coil geometries that maintain strong magnetic coupling under misalignment. After the coils have been designed, electromagnetic validation is tested using finite element analysis (FEA), which allows the magnetic field distribution to be evaluated, as well as the coupling coefficient under different scenarios of misalignment and variation in the air gap between the ground side and the vehicle side. At the same time, a comprehensive control strategy for the primary side of the system has been developed. This control method ensures power management on the primary side, enabling system interoperability for charging multiple types of vehicles, as well as reducing vehicle weight for greater range. All this is combined with an innovative pulsed current charging method, chosen for its advantages in terms of thermal stability, ensuring safe and efficient recharging that is mindful of battery health. Simulation and experimental validation demonstrate that the proposed framework maintains stable wireless power transfer and achieves over 87% DC–DC efficiency under lateral misalignments up to 100 mm, fully complying with SAE J2954 alignment tolerance requirements. Full article

Cylindrical surfaces with complex parameters (CSCPs) have off-axis and aspheric properties. High-precision measurement of cylindrical surfaces is a key research focus in optical metrology. Two-dimensional pseudo lateral shearing interferometry (2DPLSI) enables non-null generalized interferometry for cylindrical surfaces. However, due to the non-rotational symmetry of cylindrical surfaces with complex parameters, measuring them using two-dimensional pseudo lateral shearing interferometry inevitably introduces misalignment aberrations, degrading the accuracy of cylindrical surface reconstruction. To address this issue, we propose a novel non-null testing method: the cylindrical surface is translated in the orthogonal directions to carry out the shearing process, and wavefront errors are eliminated through second-order differencing. Furthermore, a reconstruction algorithm in one direction is proposed. Using only the partial derivative in the x direction, the wavefront error of misalignment aberrations can be reconstructed, enabling high-precision recovery of the cylindrical surface. Experimental results using a Fizeau interferometer demonstrate that the proposed method effectively reconstructs misalignment aberrations. The reconstructed cylindrical surface achieves a peak-to-valley (PV) value of 0.45λ (λ = 632.8 nm) and a root-mean-square (RMS) value of 0.12λ, comparable to the 0.37λ PV and 0.09λ RMS obtained via null testing. The repeatability of the proposed method is superior to λ/1000 RMS. Full article

This work investigates the geometric design and optimisation of a dynamic inductive power transfer coupler for two-wheeled electric vehicles under misalignment and magnetic-field exposure constraints. A computational three-dimensional finite-element model of a shielded rectangular coupler is developed to characterise coupling coefficients and magnetic flux density levels on control planes along the longitudinal travel range and under lateral and angular misalignments. Two simulation datasets are generated: one varying only geometric parameters at a nominal position for surrogate construction and global sensitivity analysis, and a second jointly sampling geometry, the travel range and misalignments for optimisation. Sparse Polynomial Chaos Expansions and Canonical Low-Rank Approximation surrogates are built to quantify Sobol’ indices, revealing that a small subset of primary-side geometric variables dominates both coupling efficiency and magnetic field levels. Random forest regressors are then trained on the extended dataset and embedded in the Non-dominated Sorting Genetic Algorithm II to solve a multi-objective optimisation problem that maximises worst-case coupling, improves robustness to misalignment, and enforces magnetic-field leakage limits. Optimal designs were obtained, and a subset was selected for re-evaluation using the finite-element method. The results confirm that the proposed surrogate-assisted framework yields coupler geometries with enhanced coupling and reduced magnetic field leakage while respecting the mechanical constraints for the electric motorcycle system. Full article

Autonomous vehicle path-tracking and lateral stability depend critically on reliable steering actuator operation. However, steering systems are susceptible to bias faults from mechanical misalignment, friction, drivetrain asymmetry, and degradation. These faults distort commanded versus actual steering inputs, causing accumulated lateral and heading errors during high-speed driving. Actuator biases manifest as constant offsets, gradual drift, or intermittent activations, which complicate reliable diagnosis. This study presents an adaptive sliding mode observer-based active fault-tolerant control framework for real-time detection, estimation, and mitigation. An extended four-state lateral error model incorporating distance and heading errors captures the influence of steering bias on vehicle behavior and stability. Adaptive observer gain tuning addresses modeling uncertainties arising from speed variations, linearization residuals, and tire stiffness changes to ensure robust estimation under realistic driving conditions. The effectiveness of the proposed method is validated through high-speed double lane change simulations considering three representative bias scenarios: an initial constant bias, a gradually increasing drift bias, and an intermittent bias. Results demonstrate reliable bias estimation and significantly improved path-tracking accuracy compared to uncompensated cases. Operating without additional sensors, hardware redundancies, or controller switching, the framework is suitable for practical implementation in autonomous vehicle steering systems. Full article

This paper proposes a novel magnetic coupler, a segmented bipolar pad (SBP) that outperforms the conventional bipolar pad (BP) with symmetrical geometrical dimensions. The performance parameters: mutual inductance (M_TR), coupling coefficient (k), output power (P_O), and DC-DC efficiency (η). The performance evaluation of the proposed pad is compared with the conventional pad under cases: (1) lateral misalignment (ΔY), and (2) interoperability with non-polarized pad (NPP) and polarized pad (PP). A 4.7 kW inductive power transfer (IPT) system is designed with an inductor–capacitor–capacitor-series (LCC-S) compensation network. For case 1, the M_TR of the SBP at ΔY = ±90 mm is the same as the M_TR of BP at ΔY = 0 mm, ensuring better misalignment tolerance capability of SBP. The maximum η of SBP is 93.64%, which is 4.96% greater than the highest η of BP. For case 2, the M_TR of the SBP with NPP is 22–24% and with PP is 20–25% higher than the BP interoperable performance. The obtained η shows maximum improvement of 2.46% for SBP with NPP, and 3.7% for SBP with PP when compared to the interoperable results of BP. SBP gives enhanced performance for both cases compared to the conventional pad at no additional pad design cost. The proposed work is validated through an experimental setup. Full article

Dynamic inductive power transfer (DIPT) can enable dynamic wireless charging for urban micromobility, but deployment is constrained by electromagnetic field (EMF) exposure compliance and by lateral and angular misalignment typical of two-wheeled vehicles. This review consolidates the state of the art and links these constraints to smart grid control and charging optimisation. It frames dynamic charging lanes as corridor infrastructure that behaves as a distributed electrical load whose demand depends on traffic and availability, with segmentation control as a key lever for controllability. It then synthesises practical system architectures that combine power electronics, segmented transmitters, sensing, communication, and supervisory control, because these interfaces determine which degrees of freedom are available to shape demand in space and time. The review also summarises coupler, shielding, and compensation choices that jointly determine efficiency, misalignment robustness, and EMF leakage. Finally, it surveys scheduling methods that incorporate network limits, output from distributed energy resources, and uncertainty through rolling horizon, robust, and risk-constrained formulations. The synthesis supports deployment aligned with renewable integration and sustainable urban mobility, and it highlights open needs in forecasting robustness, scalable optimisation, and secure interoperability. Full article

Dynamic wireless power transfer (DWPT) systems for in-motion electric vehicle (EV) charging often suffer from unstable power delivery due to spatial variations in magnetic coupling caused by vehicle misalignment. This study presents a stabilization-oriented DWPT design methodology that prioritizes minimizing spatial variations of mutual inductance rather than maximizing peak coupling under perfect alignment. A ferrite-backed double-D coil configuration is analyzed and refined using three-dimensional finite-element electromagnetic modeling integrated with circuit-level co-simulation to evaluate coupling behavior, magnetic field homogeneity, and power transfer efficiency under realistic dynamic misalignment conditions. The proposed design achieves a coupling coefficient of 0.50–0.55 under aligned conditions and exhibits smooth, predictable degradation for lateral offsets up to 40–50 mm. Quantitative analysis demonstrates a low spatial coupling gradient of approximately 0.001 mm⁻¹, indicating that abrupt coupling transitions are effectively suppressed during vehicle motion. The system attains a maximum power transfer efficiency of 84.37% at an 80 mm air gap, while maintaining stable performance under both lateral and vertical displacement. Comparative evaluation shows improved misalignment tolerance and coupling stability relative to conventional double-D configurations. The results demonstrate that electromagnetic field shaping focused on coupling smoothness is an effective and practical strategy for reliable dynamic wireless charging of electric vehicles. Full article

The efficiency of power transfer is a critical issue for wireless charging applications in electric vehicles. The misalignment between the transmitter coil and the receiver coil in wireless charging leads to a significant reduction in efficiency. This article investigates improving coil misalignment performance in wireless power transfer for electric vehicles using magnetic flux density analysis. The objective is to study the effect of the automatic alignment transmitter system’s movement on error distance. The automatic alignment transmitter system was integrated with a wireless power transfer system to realign the transmitter coil whenever lateral misalignment occurred between the transmitter and receiver coils. The experiment was performed with a horizontal misalignment of 0.35 m and was repeated three times. The gap between the coils was held constant at 0.15 m. The wireless charging system was designed according to the Society of Automotive Engineers (SAE) standard. The experimental results demonstrated that the movement error distance was 0.001 m, with an average error of 0.33%. These findings indicate that the automatic alignment transmitter system achieved an operational effectiveness of 99.67%. The maximum wireless charging efficiencies of 75.78% and 75.59% were recorded for the X-axis and Y-axis adjustments, respectively. Full article

Wireless power transfer (WPT) technology, leveraging the unique advantage of contactless power supply, has been recognized as a core power supply solution for mobile devices such as automated guided vehicles (AGVs) and electric vehicles (EVs). However, its transmission performance is highly susceptible to lateral offset, longitudinal misalignment, and angular deflection of the coils, resulting in a sharp decline in efficiency and unstable output. This has become a key bottleneck restricting the engineering application of the technology. This paper presents a comprehensive review focusing on the misalignment tolerance technologies for WPT systems. First, taking the LCC-S/LCC topology as an example, the influence of coil misalignment on the system output performance is analyzed, and various misalignment tolerance methods are enumerated. Subsequently, the basic principles and main research achievements of four categories of misalignment tolerance technologies, namely coupling structure optimization, compensation topology optimization, control strategies, and alignment guidance technology, are systematically summarized, with their limitations identified. Finally, the future research directions of misalignment tolerance technologies are discussed. Full article