bluuebunny/crossref_metadata_2025 huggingface dataset:
Towards Natural Movement: Integrating Sustainable Materials With Hybrid 3D Printing Techniques and In-House-Developed Smart Sensors
Authors: Habib Ahasan , Goyal Krittika , Pervaiz Salman , Bae Jun Han
Published: January 2025

The global demand for prosthetic limbs is rising due to increasing amputations, with approximately 185,000 procedures yearly in the United States. 3D printing offers a cost-efficient solution for precise prosthetic design, catering to individual patient needs. However, there’s a lack of a cohesive approach to achieve specific mechanical properties and smart sensing capabilities in 3D-printed prosthetics. This paper aims to improve prosthetic finger production by integrating hybrid materials and advanced 3D printing methods. It focuses on enhancing mechanical properties of PLA, optimizing the rheological properties of PDMS material for a better in-house 3D bio-printed sensor. Keeping in view that print quality is a complex function of different printing parameters, the study incorporated Taguchi based design of experimental (DoE) approach. For Taguchi orthogonal array L09, three parameters such as infill density, infill patterns and print speed were considered with three levels in this study. The flow behavior of PDMS at various temperatures such as 30°, 40°, 60°, and 70° was identified in terms of viscosity, shear thinning factors (n and K), zero-shear stress, and shear stress at different shear rates. Barium Titanate (BaTiO3) was combined with optimized PDMS and tested the open-circuit voltage to explore flexible tactile sensors fabrication. Different regions of a finger prothesis were manufactured using various 3D printing techniques and materials as proof of concept.
The Effects of Nonlinear Modelling on Hand Tremor Mitigation Device Design
Authors: Doughty Timothy A. , Shannon Connor , Neighbors J. P.
Published: January 2025

Parkinson’s Disease (PD) is a progressive neurodegenerative condition that impacts the nervous system and body control of over eight million people globally. Involuntary hand tremor is one of the primary symptoms associated with PD. These hand tremors affect one’s ability to perform basic motor function tasks, which can lead to frustration, anxiety, and isolation. Most treatments for PD involve medications or invasive surgeries [1]. This study is a continuation of work done in designing, prototyping, and testing a purely-mechanical, wearable device for the reduction of PD-based tremors [2]. The modeling of the biomechanical system of the hand and its interface with the device is described, with an attention to optimizing the design and performance of the new system. Nonlinearities, similar to those inherent in the physical systems, are introduced to understand and improve system performance. Testing has been performed on a mechanical hand apparatus. In comparison to the previous prototype, the weight and geometry has been reduced by 55.5% and 46.8%, respectively while the performance maintains an over 90% reduction in tremor amplitude at peak excitation.
Effect of Cooling Rate on Gas Diffusion in Metal Additive Manufacturing
Authors: Ingle Nikhil , Mohan Ram V. , Mogbolu Jonathan
Published: January 2025

Selective Laser Melting (SLM) is a promising technology that has the potential to revolutionize the manufacturing industry. One of the advantages of SLM is its ability to create custom properties in parts. However, process-induced variations like porosity and keyholes can lead to the formation of undesired structural defects, reducing the mechanical strength of the manufactured components. This paper studies gas diffusion in the powder bed during the SLM process, which can be a significant factor that can lead to the formation of porosity or voids and defects in the material, weakening the mechanical properties of the final product.

Investigations were performed using the Molecular Dynamics (MD) models developed using the LAMMPS, an open-source code to investigate the entrapment of gas atoms in the powder bed and its diffusion during the SLM process. The findings provide insights into gas particle diffusion and its effect on the microstructure during solidification. Such insights can improve understanding and control of gas diffusion mechanisms in powder beds in metal additive manufacturing parts. This study can significantly impact the optimal development of metal additive manufacturing parts with improved mechanical properties.
A Linear Programming and Deep Reinforcement Learning Framework to Choose Dwell Positions and Dwell Time in High-Dose-Rate Prostate Brachytherapy Using Curvilinear Catheters
Authors: Qian Yang , Washington Peter , Podder Tarun K. , Konh Bardia
Published: January 2025

High-dose-rate (HDR) prostate brachytherapy (BT), a popular modality for prostate cancer treatment, grapples with the challenge of optimizing dwell positions and dwell times to ensure effective radiation delivery, while minimizing damage to organs at risk. This study introduces a novel two-stage approach to address this problem, employing linear programming (LP) and deep reinforcement learning (deep RL). Using data from an anonymized prostate cancer patient, an initial plan is generated through LP model, via selection of dwell positions and estimation of their respective dwell times. This plan meets vital parameters such as V100, V150 and D10 for the prostate, rectum, bladder, and urethra. A deep RL model using the Deep Deterministic Policy Gradient (DDPG) algorithm subsequently fine-tunes this plan, further reducing D10 values, while ensuring all dose constraints are satisfied. The results demonstrate that our two-stage LP and deep RL approach yields superior treatment plans, indicating its potential to improve patient safety and treatment outcomes in HDR prostate BT.
Design of a Flapping Wing Apparatus to Measure Aerodynamic Forces Using Wing Flexibility
Authors: Rayman Bradley , Jawad Badih , Vejdani Hamid
Published: January 2025

In this paper we report on the design of an apparatus to study the force distribution on flapping wings with variable forward speed. Our motivation is to understand the generated aerodynamic forces on flapping wings to be able to design and control flapping flight robots. We used a crank-slider mechanism to actuate the two wings with a single motor and generate reciprocal motion on them while the motor moves continuously in one direction. We first analyze the kinematics of the mechanism and find appropriate relation between the dimensions. Then we construct the equation of motion of the system including the aerodynamic forces. Using the simulation, we determine the gear ratio needed for this apparatus. After that we explain the process for CAD design and integration of the different parts. At the end we presented the final apparatus.
Bilateral Airflow Dynamics in Unilateral Cleft Nasal Deformities: Pre- and Post-Surgical Analysis
Authors: Charles Daniel , Harrison Lucas , Hallac Rami R. , Hassanipour Fatemeh
Published: January 2025

This study builds upon previous computational fluid dynamics (CFD) analyses by further investigating the nasal airway in unilateral cleft lip and palate (UCLP) patients post-LeFort I osteotomy. Using the same patient-specific models, we conducted a detailed comparison of the left and right nasal chambers, focusing on key aerodynamic parameters including airflow velocity, pressure distribution, nasal resistance, and changes in volume. Our findings reveal significant asymmetries between the two chambers, with the cleft side exhibiting distinct variations in flow dynamics and resistance compared to the non-cleft side. Postoperative results indicate a more balanced airflow and reduced nasal resistance, contributing to enhanced breathing efficiency. These insights provide a deeper understanding of the functional outcomes of surgical interventions in UCLP patients, emphasizing the importance of considering bilateral nasal airflow dynamics in surgical planning and evaluation.
Experimental Investigation of a Wind Turbine Gearbox for Prognostics and Health Management
Authors: Ayivor Fredrick J. , Askarian Behnam , Neal Byron A. , Alemayehu Fisseha M.
Published: January 2025

The reliability of wind turbines is critical to enhance the contribution of wind energy as a dependable source of Renewable Energy. Nevertheless, wind turbine gearboxes (WTGs) fail in the first half of the wind turbine’s expected life, which is usually 20–25 years. The repair/replacement of WTGs is very expensive, and the downtime is extremely long. These failures of WTGs significantly diminish the reliability of these devices and in turn deteriorate the confidence of investing in renewable energy systems. The wind energy industry is approaching this issue in two ways: enhancing the reliability of WTGs or abandoning the use of gearboxes by using multi-pole permanent-magnet generators, i.e., a direct drive system. This current research is focused on enhancing the reliability of WTGs via the implementation of Prognostics and Health Management (PHM) to avoid unexpected early failures of WTGs. A 40/60kW wind turbine drivetrain test-rig is built from a decommissioned small-scale wind turbine to conduct the study. The system is driven by a VFD controlled, 60 HP motor (to simulate the input torque from the rotor) and has an integrated 5 Degree of Freedom Load Application Device (5 DoF LAD) to simulate the non-torsional loading that a real-world wind turbine drivetrain would experience due to wind shear, directional shear, and weight of the rotor. The system, with non-faulty (baseline) as well as faulty planet gear bearings, under different loading conditions has been tested and the state of the system was recorded via accelerometers, strain gauges and acoustic sensors in different locations. Data sampling frequency for all sensors has been determined using Shannon-Nyquist Sampling Theory and collected data has been analyzed and compared to understand responses of baseline as well as faulty systems and conclusions have been drawn for future implementation of PHM for remaining useful life (RUL) prediction.
Improved De-Bonding of Composite Adhesive Joints With Bondline Inserts
Authors: Tedlapu Khushboo , Gerini-Romagnoli Marco
Published: January 2025

The demand for effective de-bondable adhesive technology enabling substrate separation under small loads has grown in recent years. Thermally Expandable Particles (TEP) can be embedded in structural adhesives to promote mechanical separation of the adherends. However, the activation of TEP additives in joints with non-metallic adherends is challenging and can result in substrate thermal damage and poor de-bonding performance, due to the low thermal conductivity and dielectric loss factor typical of plastics and polymer-matrix composites.

In this study, the effect of bondline stainless steel inserts on fully composite (Carbon Fiber Reinforced Polymer, or CFRP) bonded Single Lap Joints (SLJ) mechanical and de-bonding performance is evaluated. A centrifugal mixer is used to disperse the TEP in the adhesive. TEP additives are activated using induction heating of the bondline insert, which also helps control crack initiation and propagation. SLJ de-bonding tests are run under a constant 20 lb (89 N) load, and substrate temperature is recorded with thermocouples and an infrared thermometer. Joint strength is evaluated with quasi-static lap shear tests on a servo-hydraulic tensile test apparatus.

Preliminary de-bonding testing is performed on a broad initial set of 316 stainless steel insert designs. Out of those, the four best-performing insert geometries are chosen for the complete study. Two TEP enrichment levels (10% and 20% wt.) are investigated. The mechanical and de-bonding performance of SLJs with steel inserts is compared to TEP-only baseline fully-composite and multi-material (AA 6061 Aluminum Alloy + CFRP) joints.

The results show that bondline inserts enable fast de-bonding of fully-composite SLJs. Insert geometry and thickness affect joint de-bonding time and reliability, and can be optimized to allow for a partial recovery of lap shear strength. 100% de-bonding reliability is achieved with “block”-type inserts, with de-bonding performance similar to TEP-enriched metallic joints. Visual inspection of the fracture surfaces shows the relationship between TEP activation and crack propagation path. Discussion and conclusions are provided.
Elderly Occupant Human Body Model: Comprehensive Development and Validation for Frontal Impact Scenarios
Authors: Somasundaram Karthik , Harinathan Balaji , Yoganandan Narayan
Published: January 2025

Due to changes in structural and material properties, elderly vehicle occupants are at increased risk of injury. Given the current growth of this population, understanding injury mechanisms and designing countermeasures for the elderly population are of utmost importance. Therefore, the objective of the current study was to develop a vehicle occupant human body model representative of the elderly population that can be further used to design countermeasures. To this end, a 75-year-old (75YO) Global Human Body Models Consortium (GHBMC) model was developed by morphing the baseline 50th percentile GHBMC model geometry and material properties to the elderly. The developed elderly model showed a good correlation with elderly experimental responses for thorax impacts, abdomen impacts, and frontal sled tests.
Design, Calibration, and Validation of a Robust and Reliable Nanofuel Stability Analyzing Device
Authors: Nagarkar Nitin , Steiner Wesley , Mollick Rahat , Ratner Albert
Published: January 2025

Nano-fuels present a promising avenue for enhancing combustion properties and reducing emissions, but their practical utilization is hindered by stability issues such as nanoparticle agglomeration and settling. This study introduces an enhanced experimental setup for analyzing nanofuel stability, leveraging light scattering techniques. The setup, featuring a 3D-printed component with integrated LEDs and photodiodes, boasts a 20% increase in spatial resolution and a 35% reduction in wiring complexity compared to prior configurations. Furthermore, PCB-designed circuitry and a dedicated housing unit ensure durability, reliability, and portability. Calibration tests validate the setup’s accuracy, demonstrating consistent sensor readings across various sample types, including water, opaque, and biodiesel. Comparative analysis of settling delay and trends for acetylene black (AB) nanofuels highlights improved settling times over previous setups employed by Singh et al. and Mollick et al. [3,7]. Notably, the study reveals a metastable settling state and a diminishing settling rate over time, shedding light on the intricate behavior of nanofuels during settling processes. Overall, this research highlights the significance of nanofuel stability analysis for understanding nanofuel settling behavior. The refined experimental setup offers a cost-effective, non-invasive solution with promising industrial applicability.
Influence of Number of Shock Waves on Rotating Detonation Engines Performance
Authors: Pereira Rita , Brójo Francisco , Silva João
Published: January 2025

In recent years, detonation combustion has been revolutionary in the aeronautical and aerospace sector with great interest in its application in the Rotating Detonation Engine (RDE) which performs the combustion process continuously, providing reductions in specific fuel consumption and gains in efficiency compared to rocket engines and gas turbines. The mechanical simplicity of RDE requires only one ignition sequence to initiate the detonation wave that propagates at supersonic speeds in a compression shock wave self-sustainedby the heat release in combustion.

The simplicity of the RDE structure and its advantageous features make this innovative concept a possible future solution as a stand-alone engine for aerospace propulsion. However, this concept still requires a great deal of research and development work. Therefore, taking into account the investigations on this topic, the motivation for this work is related to the need to understand the phenomenon of detonation that governs the operation of the RDE, whose performance depends on the inevitable irreversibilities of its achievable project.
A Benchtop Study of Fontan Circulation
Authors: Damon Anthony , Das Arka , Prather Ray , Kassab Alain , Divo Eduardo , DeCampli William
Published: January 2025

The Centers for Disease Control and Prevention (CDC) estimates that each year in the United States, approximately 1/3800 babies are born with only one functioning ventricle. The Fontan circulation is a result of the third stage procedure to correct single ventricle anatomy in children whose implementation has only led to a survival rate of ∼50% into adulthood. One of the failure points recognized is increased inferior vena cava (IVC) pressure within the total cavopulmonary connection. The research team proposes to enhance flow into the pulmonary system by adding an injection jet shunt (IJS) to induce flow entrainment by drawing flow directly from the aortic arch, balanced by a fenestration to maintain a ratio of pulmonary flow (Qp) to systemic flow (Qs) of 1. Therefore, oxygen tracking is critical to determining the optimal IJS-assisted Fontan model geometries for a given patient. In this study, we describe a dynamically controlled mock flow loop model (MFL) designed to quantitatively and qualitatively estimate the volume fraction of IJS flow (VFIJS) absorbed by the fenestration in the IVC conduit using a high-speed fluorescence technique called ultraviolet-induced fluorescence (UVIF). A patient, generic surrogate model of the total cavopulmonary connection (TCPC) with average dimensions matching those of a 2–4-year-old patient is inserted in the MFL derived from a reduced lumped parameter model (LPM) representing the cardiovascular circulation using four 2-element Windkessel compartments. Using UVIF to image hemodynamic flow field at high temporal scales comes at the expense of low spatial resolution which is addressed by implementing a mechanism to increase spatial resolution while preserving temporal scale. This is done using a proper orthogonal decomposition (POD)-trained radial basis function (RBF) interpolation network to increase the resolution of the VFIJS snapshot. Spectral proper Orthogonal decomposition (SPOD has been performed to characterize the spatiotemporal components of the dominant coherent structures of the jet-entrained flow field in the Fontan conduit. To this end, a precise mechanism for capturing the volume fraction of the entrained jet in the Fontan conduit has been developed utilizing the UVIF-based imaging technique with a SPOD-POD-trained RBF interpolation network. The experimental results obtained in this study follow the trends as reported in the in-silico findings.
Systematic Review of Endodontic Irrigation – Standardization of the Irrigation Procedure
Authors: Kocharian Tikran , Manoharan Sanjivan
Published: January 2025

Root canal therapy, also known as endodontic treatment, is a dental procedure to treat the infected pulp of a tooth. A series of steps are done by the dentist during this treatment including X-ray imaging of the tooth, mechanical preparation and extraction of the pulp, irrigation of the root canal, and filling of the cavity. Of these steps, the root canal irrigation is particularly crucial as a significant number of root canal procedures encounter challenges at this stage. Despite its importance, no standardized endodontic irrigation procedure exists to date. Discrepancies in irrigation techniques can result in inconsistent success rates, with research suggesting as low as 65% efficiency. While a variety of factors control the irrigation procedure, it is troubling to note that attempts to create a universal endodontic database are absent. As a first step, an initial survey was conducted among a few endodontists to gauge their perspectives on establishing and maintaining such a database. Additionally, the respondents were asked to rank the key factors influencing irrigation while also offering insights into how they assess the effectiveness of an irrigation process. This paper is the first step towards developing a standardized irrigation protocol that can be incorporated into endodontic education programs.
Manufacturing, Characterization and Terrestrial Passive Radiative Cooling Performance of Nanofibrous PTFE-PEO Composite Thermal Coatings
Authors: Ibekwe Chieloka , Wang Xuanjie , Hartwig Jason W. , Swanger Adam M. , Narayan Shankar
Published: January 2025

Passive heat management is desirable in many applications since it can reduce the energy expended for cooling, for example, in buildings and automobiles. Specifically, materials with wavelength-dependent reflectance and emittance can manage incident solar fluxes while enabling passive radiative cooling by thermal emission. This study demonstrates the use of polymeric nanofibers, specifically polytetrafluoroethylene (PTFE) and polyethylene oxide (PEO) composite, as thermal coatings for passive temperature control. Employing the electrospinning fabrication process, we engineer nano and micro-scale fibrous structures, studying the influence of fabrication parameters, such as precursor material concentration and rotating collector speed, on fiber geometry and optical properties. To understand the role of material and fiber geometry on optical performance, we characterize various samples’ spectral reflectance, absorptance, and transmittance using spectrophotometers interfaced with integrating spheres. The results show the potential of nanofabricated PTFE-PEO coatings as promising candidates for passive thermal control. We highlight their competitive edge by comparing their solar reflectance and emittance values to existing passive radiative thermal control materials. In essence, this study contributes to advancing passive heat management technologies, offering insights into optimizing material composition and fabrication techniques for enhanced performance in various applications.
Enhancing Photovoltaic Solar Panel Efficiency via Computational Fluid Dynamics (CFD) Cooling Analysis
Authors: Azari Fatemeh , Jazaei Robabeh , Gharehdaghi Samad
Published: January 2025

This paper computationally evaluates the effectiveness of integrating fins in increasing the efficiency of Photovoltaic Solar Systems. Building on previous Finite Element Analysis (FEA) that contrasted the performance of bare panels against those equipped with rectangular and cylindrical heat sinks, this investigation primarily concentrates on Computational Fluid Dynamics (CFD) models executed within ANSYS Fluent. Through simulations under laminar and turbulent conditions, characterized by Reynolds numbers of approximately 2000 and 6000, respectively, the study introduces significant simplifications by considering a solitary PV layer, a single fin, and a fluid domain. This approach significantly economizes computational resources. Comparative analysis with FEA data indicates that bare panels and panels with pin fins achieved efficiencies of 14.63% and 19.34%, respectively, underscoring the efficacy of utilizing water as a coolant and optimizing flow velocity. Additionally, results reveal that the laminar and turbulent CFD models exhibit average temperatures of 25.19°C and 25.18°C, respectively, correlating to the efficiency of 19.71% thereby marking an insignificant uptick from the turbulent to the laminar model.
Active Machine Learning Empowered Digital Twin Modeling for Heat Sink Design
Authors: Coaty Jacob , Wu Hao , Minary Majid , Xu Yanwen
Published: January 2025

As electric vehicles (EVs) and plug-in hybrid vehicles (PHEVs) become increasingly prevalent, efficient thermal management of power inverters and converters is crucial for safe operation and prolonged lifespan. The design process of heat sink often necessitates an optimization phase that can be computationally intensive due to the repeated, intricate analyses of the system. This paper addresses the challenges in designing and manufacturing effective cooling systems for these components, introducing a cutting-edge methodology that leverages active machine learning to empower digital twin modeling for heat sink design. Traditional methods involve time-consuming physical prototyping and disconnected design-manufacturing processes, leading to prolonged development cycles and high costs. To overcome these challenges, a novel digital twin platform is proposed, integrating physics-based modeling with advanced data-driven techniques. The platform utilizes a multiphysics simulation model for constructing the physical twin and employs an active machine learning (AML) approach based on Gaussian process (GP) modeling for the digital twin. Our approach begins with offline experiments and extends to an online AML framework, facilitating real-time interaction with the physics model for deployment in production settings. By strategically leveraging labeled samples, our method outperforms random data point selection, resulting in a notable enhancement in surrogate modeling efficacy. This innovative approach offers a more efficient system performance evaluation and automatic uncertainty quantification, guiding the exploration of optimal heat sink designs while reducing energy consumption and development costs. The paper discusses the proposed method, presents a numerical example, and concludes with insights into the efficacy of the approach for enhancing thermal management in electric vehicle systems.
Materials Traceability Aiming Zero-Defects Manufacturing In Cloud Based Solutions in Construction Sector
Authors: Ferreira José , Mendonça João Pedro , Soffer Tal , Jardim Gonçalves Ricardo
Published: January 2025

The construction sector is developing rapidly around the world, to the extent that companies are actively exploring opportunities with emerging technologies. However, the construction sector is the lowest-ranked economic sector in terms of digital adoption in Europe and with a lot of opportunities to explore, according to a leading EU industry organization. In addition, being one of the sectors that creates the most waste, and with EU intending to reduce waste and the use of virgin raw materials, it is important to start implementing solutions to mitigate the waste volume. This paper presents a solution that tracks materials from production to installation in the construction site, making it possible to identify where the materials are delivered, and whether they are delivered on time and control the quality of the materials. Giving the ability to reduce waste, excessive use of materials will improve construction quality. This paper demonstrates the connection between different suppliers and the construction company, and serves as a good example of good practice of IoT use to monitor the production of materials and delivery to the construction site, validating the innovative concept between Edge to the Cloud. The result was the development of a solution centralised in the Cloud and interconnected with solutions installed in factories (Edge solutions) with support for sensors to be able to monitor production in real-time, to provide updates on the status of production, and identify whether possible delays in materials have an impact on construction deadlines.
Accelerated Fatigue Measurements Using a Vibration Assembly Which Loads Two Specimens Simultaneously
Authors: Furman Brandon A. , German James E. , Wagner Jeffrey M. , Berke Ryan B.
Published: January 2025

Fatigue testing is notoriously slow, requiring many hours to obtain 1 data point on an S-N curve. Such tests can be accelerated somewhat by using vibration-based techniques, which load on the order of kHz, such that tests which would traditionally have taken multiple days can now be completed in a few hours. This work presents a novel assembly that can further accelerate fatigue testing campaigns by loading multiple specimens simultaneously. The assembly has two resonant modes of interest. The lower frequency mode puts a slightly higher strain on one specimen, and the higher frequency mode puts a slightly higher strain on the other specimen. By alternating between the two modes, fatigue loads are rapidly applied until one specimen fails, during which the unfailed specimen will have experienced the same number of cycles, and therefore has less time remaining until its own failure. The test is paused while the failed specimen is removed and replaced by a fresh specimen. Testing continues in this fashion, alternating between the two resonant modes, until a sufficient number of data points have been maintained to map out an S-N curve. Because the assembly loads two specimens simultaneously, the system is nearly twice as efficient compared to testing all specimens individually.
Koalby: A 3D Printed Humanoid Robot Based on the Poppy Platform
Authors: Beazley Raymond , Engdahl William , Lehman Alexandria , Fournet David , Galgano Anthony , Radhakrishnan Pradeep
Published: January 2025

Robotic research on humanoid robots often involves expensive hardware. Using modern manufacturing techniques and off the shelf components, a small humanoid robot can demonstrate many of the capabilities of larger systems at a lower price point. We present a 27 degree of freedom humanoid robot based on the open-source Poppy Project. The robot operates untethered using internal battery power and an onboard Raspberry Pi and is capable of manipulating objects up to 100 grams. The robot weighs 4 kg and is 85 cm tall. The robot is constructed from Digital light processing (DLP) printed components that are easily modified to support alternative motor choices. Resin 3D printing is used to minimize weight via pocketing and allows types of resin to be mixed in ratios based on whether a part needs stiffness or overall strength. Each joint is controlled by one of several types of smart actuators with integrated position control. We demonstrate this functionality using a record/play system that allows a human operator to manually position the robot and then record those positions for later playback. The paper will describe the implementation, challenges faced and future work.
Controlling the Position of a Stepper Motor Using Conventional Control Approach Embedded in a PLC
Authors: Jaswal Anshul , Abu-Ayyad Ma'moun , Lad Yash , Attaluri Anilchandra
Published: January 2025

In this paper, a non-conventional control strategy is integrated with a Programmable Logic Controller (PLC) for the precise position control of an integrated Stepper Motor (SM). Special function modules were used to generate the pulses and to read the encoder signal from the motor. IEC 61131-3 programming code was incorporated in the form of ladder logic diagram, function blocks, and structured text. This research focuses on the control of position and speed of the motor, leveraging the capabilities of control strategies embedded within a PLC. Proportional Integral Derivative (PID) which is one of the traditional control strategies used in industrial automation processes is implemented within PLC next engineer. This research integrates control strategy into PLC platforms to achieve superior control accuracy. The study uses a combination of simulation, experimentation, and real-world application to validate the proposed approach’s effectiveness. The inbuilt PID block within PLC was implemented and later the PD model developed and compiled in Simulink was integrated with PLC. The study shows that importance of sampling time and micro stepping in achieving precise positioning. The findings demonstrate that there was successful integration of Simulink with PLC for implementing control strategies. Detailed analyses of motor position and speed under varying conditions highlight the system’s adaptability and responsiveness. PD (Proportional Derivative) showed effective results in controlling the position by minimizing the overshoot. This research concludes that the integration of Simulink with PLCs offers a robust solution for achieving precise and dynamic control over motor position.
Shape Fabrication of Soft-Magnetic Composite Stator Cores Through Spray-Forming
Authors: Guralnick Brett W. , Krishnasamy Jay , Hosek Martin
Published: January 2025

This paper presents spray-forming, an additive deposition process, to produce soft-magnetic composite stator winding cores. The process involves depositing particles comprising a ferro-magnetic core and an insulating shell at high speeds and temperatures into a mold located on a build plate to produce a near-net shape soft-magnetic composite material. The resulting material is a dense matrix of ferro-magnetic domains separated by insulating boundaries, with superior mechanical strength and thermal conductivity compared to soft-magnetic composites produced through conventional compaction processes. In addition, the spray-forming process outlined facilitates the fabrication of shapes in a near-net manner, with dimensional tolerances within 0.125μm, eliminating most post-machining operations. The paper illustrates a method to produce stator components in near-net shape, using the example of a stator winding core of an axial-flux motor that features three-dimensional flux flow.
Volumetric Evaluation of Thickness of 3D Object Using Maximum Inscribed Cubes
Authors: Inui Masatomo , Umezu Nobuyuki
Published: January 2025

The thickness of a part is one of the fundamental parameters in machine design, requiring a thickness definition that is suitable for complex shapes and can be visualized in an easy-to-understand manner. Conventional methods define thickness using the maximum inscribed sphere, which causes the corners of the part to be judged as thin. In this study, we proposed a method in which the thickness of a point inside a part is defined by the width of the maximum inscribed cube encompassing the point. Using this method, the thickness of a part can be defined more appropriately than with conventional methods. Software was developed to convert the part geometry into a voxel model and calculate the thickness value of the center point of each voxel. Furthermore, a volume rendering technique was developed to properly display the voxel model with the obtained thickness values. Software was implemented to visualize the thickness distribution inside a polyhedral model of a machine part, and its effectiveness was verified by applying it to several parts.
A Human-Robot Interaction Platform for Operator Well-Being: A Case-Study
Authors: Venkateswaran Swaminath , Charafeddine Jinan
Published: January 2025

This article presents a Human-Robot Interaction (HRI) platform for the assembly process of a condensate pump. An ergonomic analysis using the Rapid Upper Limb Assessment (RULA) is carried out using a simulation package to identify the fatigue levels in the upper-arm region during the assembly process of the pump. From the operator feedback and the RULA score, an HRI platform using a collaborative robot (cobot) is proposed for the assembly process. Based on complexity and dexterity, the screwdriving operation was assigned to the cobot. The RULA analysis was revisited for this platform and it showed an improvement in the ergonomic scores from 7 to 3. The magnitude of fatigue imposed on the upper-arm was then analyzed experimentally using Electromyography (EMG) sensors. By using the Support Vector Machine (SVM) technique, the fatigue levels were interpreted before and after the implementation of the HRI platform. The results suggest that the HRI platform helps to mitigate musculoskeletal problems in the future, thereby promoting a healthier and safer worker environment. By exploiting the capabilities of a cobot, a synergy between humans and automation technologies can be achieved, leading to a sustainable and ergonomic future in manufacturing.
Compressive and Flexural Studies on Different Core Materials Made Using Nanoclay, Polyurethane Foam and 3D Printed PLA Lattice Constructions
Authors: Gorijala Durga Prasad , Hosur Mahesh , Bommarapu Deepak , Gonzales Job , Mogiligidda Rajashekar
Published: January 2025

Sandwich composite structures are extensively used in automotive, aircraft, rapid transport, and naval industries due to their reduced weight, high rigidity, and low maintenance costs. This type of material has top, bottom face sheets and a low density thick core material sandwiched between the face sheets. Face sheets are fiber reinforced polymer matrix composites. Core materials are usually cellular foam, aluminum in the form of honeycomb and different types of lattice structures.

Nowadays, 3D printing or additive manufacturing (AM) grabs researchers’ attention towards its accuracy in printing of most complex structures. Fused deposition modeling (FDM) is traditionally known AM technology in the world. Taking advantage of AM technology, in this study three different hallow lattice core structures were designed using Autodesk Inventor CAD software and printed using Polylactic acid (PLA) as 3D printing material. In addition, 2-part polyurethane foam cores were created i.e. both un-modified and modified by four different types of nanoclay at 0.5 and 1 wt.% loading. These nanoclays were used to change the density and properties of PU foam. Also, both modified and unmodified PU foam was used to fill the space in lattice in a closed mold to keep the foam within the lattice to create foam fill lattice cores.

Quasi-static compression and 3-point bend flexure tests were conducted on these core materials. Results of the tests showed that all the foam core samples with nanoclay had higher flexural properties compared to the foam without nanoclay. N2 0.5% PU has the highest flexural strength and compressive force of 2840N compared with all other foams. 3D printed lattice performed better than all types of foam samples when subjected to compression and flexure tests. The compressive force of foam filled lattice structures are higher than lattice samples and lattice samples are higher than neat/nanophase PU foam samples. Addition of nanoclay makes foams brittle and hence they had lower deformation. Except for zero vertical, all lattice constructions with or without foam sustained load that was up to the capacity of testing machine, which was 5.5kN. Compressive modulus of nanophased foams increased in the range of 370 and 500%, whereas for the lattice constructions the increase was in the range of 650 to 900%. For the foam filled lattices, it was slightly lower in the range of 485 to 682%. Under flexural loading, there as modest increase in the secant modulus and flexural strength for nanophased cores. For lattice constructions, the secant modulus increased in the range of 331–407%, while the flexural strength increased in the range of 121 to 218%. The increase in the secant modulus for foam filled lattices was in the range of 3 to 37%, and the flexural strength in the range of 9 to 41%. Bonding between foam and lattices was not strong and caused premature failure under flexure.
The most efficient thermodynamic cycle under general engine constraints
Authors: Ong Christopher , Quek Shaun
Published: January 2025

Carnot's theorem guarantees the most efficient cycle to be the Carnot cycle provided that the state space is constrained between two isotherms. This paper considers what the most efficient cycle would instead be if the state space is constrained differently. We construct a general formalism for deriving the most efficient cycle in any constrained state space. We study the specific case of a rectangular domain on the P−V space, and we prove that the Brayton and Otto cycles are the most efficient.
Teaching quantum mechanics within a nature-of-science framework
Authors: Giliberti Marco , Lovisetti Luisa
Published: January 2025

We know from physics education research that, for effective physics teaching, knowledge needs to be framed within a context where the nature of science plays an essential role. This work presents the framework we have developed for introducing pre-service and in-service teachers to quantum mechanics via an active learning approach. It starts with some selected elements of the history of quantum mechanics, develops a set of physical principles, and then motivates constructing the formal aspects of quantum mechanics, such as states, linearity, superposition, observables, and probability.
Ergodic Lagrangian dynamics in a superhero universe
Authors: Tregillis I. L. , Martin George R. R.
Published: January 2025

We present a fictional scenario that, while undeniably whimsical, provides the foundation for a unique exercise in extended problem solving, physics analysis, and quantitative model development. Starting with the foundational premise of the Wild Cards shared-world superhero universe, we demonstrate how a variety of concepts appropriate to the advanced undergraduate level—ergodicity, functional analysis, Lagrangian mechanics, and the ever-important simplifying approximation—can be combined into a rich, coherent mathematical model. The goal of this case study is to develop a useful pedagogical exercise in exploring an open-ended research question that presents, at first glance, no clear path forward. Being both eclectic and lengthy, this exercise offers a unique way for students to apply their core physics and mathematics education. It is perhaps best used within a senior honors seminar or within a brief (e.g., January term) elective class.
Broadband wireless battery-free acoustic identification tags for high data-rate underwater backscatter communication
Authors: Bhardwaj Ananya , Erturk Alper , Sabra Karim G.
Published: January 2025

Developing persistent and smart underwater markers is critical for improving navigation accuracy and communication capabilities of autonomous underwater vehicles (AUVs). A wireless acoustic identification tag, which uses a piezoelectric transducer tuned in the broadband ultrasonic range (200–500 kHz), was experimentally demonstrated to achieve highly efficient power transfer (source-to-tag electrical power efficiency of >2% at 6 m) and concurrent high data rate and backscatter level communication (>83.3 kbit s−1, >170 dB sound pressure level at 6 m) with potential operating range ≈ 10 m based on analytical extrapolations. Parameter selection considerations dictated by the desired range and data-rate requirements in communication are presented. The transducer piezoelectric element selection, impedance matching approach, and simulation-based circuit optimization for frequency multiplexed operation are also detailed. Experimental tests benchmarking performance sensitivity to source and tag misalignment are introduced and implications for AUV operations are discussed.
Clairvoyant performance bounds for adaptive beamforming in pulse-echo imaging
Authors: Geréb Gábor , Lønmo Tor Inge Birkenes , Hansen Roy Edgar , Näsholm Sven Peter , Austeng Andreas
Published: January 2025

In adaptive beamforming, the array signal processing adjusts its sensor delays and weights based on the incoming data. In conventional beamforming, these parameters are instead given from a predefined model. Adaptive beamformers can improve measurement precision by dynamically rejecting spatial interference. While an established theory is available on the behavior of adaptive beamformers in textbook scenarios, their expected performance on realistic pulse-echo imaging scenes is still mostly uncharted. Imaging performance can be evaluated by individual pixel precision and aggregated metrics such as resolution and contrast. The achievable gain is strongly related to the sparsity of the scene and the availability of data to appropriately estimate the spatial covariance matrix. In pulse-echo measurements, the nonstationary interference poses a special problem for adaptive beamforming, which is a current research question of academic and industrial interest. The current work establishes a performance bound for adaptive beamforming in simulated realistic pulse-echo scenarios. This is derived and numerically implemented as the clairvoyant minimum variance distortionless response beamformer. The proposed framework allows for an a priori assessment of the applicability of adaptive beamforming, for a given scenario. The performance of the implemented algorithms can be directly compared with the theoretical limit in a simulated environment.
In search of the female form
Immaculate Forms: A History of the Female Body in Four Parts
Helen King
Basic Books, 2025. 480 pp.
Authors: Mulder Tara
Published: January 2025

Bodies have long resisted easy categorization
Adaptations in surprising places
Authors: Rosvall Kimberly A.
Published: January 2025

Testosterone is controlled while it circulates in the bloodstream
Decoding lysosome communication
Authors: Pullamsetti Soni Savai , Savai Rajkumar
Published: January 2025

Lysosome interaction with other organelles may be linked to pulmonary hypertension
Misreported meals skew nutrition research data
Authors: Offord Catherine
Published: January 2025

Survey-based studies linking diet patterns to health may be fatally flawed, paper suggests
Associations of objectively measured physical activity and sedentary time with all-cause mortality in Japanese older adults: a 10-year prospective study
Authors: Chen Tao , Chen Sanmei , Honda Takanori , Kishimoto Hiro , Nofuji Yu , Narazaki Kenji
Published: January 2025

Objective

To examine the associations of accelerometer-measured physical activity and sedentary time with all-cause mortality in older Japanese adults.

Methods

A total of 1723 independent Japanese adults aged ≥65 years were followed from 2011 to 2021. Moderate-to-vigorous physical activity (MVPA), light physical activity (LPA) and sedentary time were measured using a triaxial accelerometer secured to participants’ waists.

Results

Over a median follow-up of 9.9 years, 336 deaths were recorded. When examined as tertiles, higher MVPA (both ≥10 and <10 min bouts) and LPA were associated with a lower mortality risk. Additional adjustment for MVPA attenuated the associations of LPA, but the HRs in the highest tertile remained significant. Longer sedentary time was significantly associated with an increased mortality risk, but not after adjusting for MVPA. In spline analyses, a linear dose–response association with all-cause mortality was observed for LPA, while the HRs declined progressively with higher levels of MVPA until approximately 80 min/day, beyond which they levelled out. Replacing 10 min/day of sedentary time with MVPA but not LPA was associated with a 12% lower risk of morality (HR 0.88; 95% CI 0.83 to 0.93); the HR for replacing 10 min/day LPA with MVPA was 0.89 (95% CI 0.84 to 0.95). These results were materially unchanged when excluding deaths within the first 5 years of follow-up.

Conclusion

Physical activity, regardless of intensity, was associated with a lower all-cause mortality risk among older Japanese adults. Replacing sedentary time or LPA with MVPA was associated with a lower mortality risk. The mortality benefit started from a low MVPA dose and additional benefits were associated with higher doses.