bluuebunny/crossref_metadata_2025_split huggingface dataset:
Synergy Based Design of a Hand Exoskeleton With Dual Actuation for Three Finger Groups
Authors: Portillo Perla , Saldajeno Ezekiel John , Sharifi Mojtaba 
Published: January 2025

Abstract
Each year, numerous individuals experience strokes and other medical conditions that result in the loss of hand movement. To regain this movement, they often undergo physical therapy, which can be both costly and time consuming due to the complex musculoskeletal structure of the hand and the high level of skill required for rehabilitation. The intricate nature of the hand makes it challenging for some patients to quickly restore movement. To address this challenge, researchers have developed assistive devices, such as hand exoskeletons, to facilitate the rehabilitation process. These exoskeletons use external power sources to control and move the user’s fingers, enabling them to perform routine or therapeutic exercises. In addition, hand exoskeletons can reduce the cost of physical therapy by allowing users to perform exercises independently, without continuous physical assistance from a therapist.
This study aims to design a novel, synergy-based mechanism for a hand exoskeleton that can move three groups of five fingers using only two actuators. The two synergies employed are the primary ones identified in the literature based on hand anatomy. The three finger groups are defined as follows: Set 1 consists of the pinky and ring fingers, Set 2 includes the middle and index fingers, and Set 3 comprises the thumb. The developed hand exoskeleton utilizes two linear actuators to move these finger groups, enabling the hand to perform grasping motions effectively.
Modeling and Simulation of 7000-Series Aluminum Extrusion Process for Complex Curtain Structure Profile
Authors: Nguyen Thanh-Cong , Hsu Quang-Cherng , Truong Tat-Tai 
Published: January 2025

Abstract
The extensive range of applications for aluminum alloys in the 7000 series is linked to their excellent mechanical properties; however, this also restricts their formability, especially with the extrusion process. Practical extrusion die design depends on the traditional “test-and-revise” process to cover all the complicated influence factors, which costs a lot of time and resources. Recently, researchers have investigated the aluminum extrusion process by applying simulation software to overcome those challenges. This study aims to utilize different approaches to virtual simulations, including steady-state simulations with the finite element method and transient simulations based on the finite volume method. It gave overall comparison results to gain a better understanding of the 7000-series aluminum extrusion process for complex curtain structure profiles. Details of the material flow in the die and the extrusion force in both types of simulations have been compared and analyzed. The notable difference in force prediction between transient and steady-state simulations for AA7005 (up to 457 tons) compared to AA7075 (only 41 tons) highlights the critical influence of input parameters, particularly the flow stress data. In addition, transient simulations required a significantly longer amount of time to run than steady-state simulations, typically around 10 times.
Thermally Induced Stress and Deflection in Cantilever Beam
Authors: Mohammadzadeh Ali , Haidar Salim M. , Norouzi Mahdi 
Published: January 2025

Abstract
In the absence of mechanical loads, temperature gradients could cause significant stresses in a solid body. In turn, this could lead to failure of mechanical and structural parts. In a typical undergraduate mechanical engineering curriculum, students are introduced to the concept of mechanical stress in solid bodies during sophomore or early junior year of their studies. They have no exposure to heat transfer and temperature field in a solid body until later in the curriculum. As such, students’ study of thermally induced stresses is limited just to statically indeterminant axial loads due to uniform temperature rise, and in the absence of temperature gradient in the body. Therefore, they are not aware of thermal stresses induced solely by temperature gradients in a solid body and the harmful effects they can cause even in the absence of mechanical loads. In this paper we present a complete model for introducing our students to this important aspect of design of structural parts and mechanical components. It would also make for a great term-long project in either heat transfer class or machine design course. It is believed that students in either of these two senior-level courses possess the technical maturity both in stress and heat conduction analyses to handle such a project.
Enhancing the Structural Performance of 3D Printed Objects Through G Code Optimization via FEA in the FDM Process
Authors: Shahriar Saquib , Islam Razaul , Park Jaejong 
Published: January 2025

Abstract
Additive manufacturing, an innovative process that assembles materials layer by layer from 3D model data, is recognized as a transformative technology across diverse industries. Researchers have extensively investigated the impact of various printing parameters of 3D printing machines, such as printing speed, nozzle temperature, and infill, on the mechanical properties of printed objects. Specifically, this study focuses on applying Finite Element Analysis (FEA) in G code modification in Fused Deposition Modeling (FDM) 3D Printing. FDM involves extruding a thermoplastic filament in layers over a build plate to create a three-dimensional object. In the realm of load-bearing structures, the Finite Element Analysis (FEA) process is initiated on the target object, employing the primary load to identify areas with high-stress concentrations. Subsequently, optimization techniques are used to strategically assign printing parameter combinations to improve mechanical properties in potentially vulnerable regions. The ultimate objective is to tailor the G code, a set of instructions for the printer, to strengthen particular areas and improve the printed object’s overall structural integrity. To evaluate the suggested methodology’s efficacy, the study conducts a comprehensive analysis of printed objects, both with and without the optimized G code. Simultaneously, mechanical testing, such as tensile testing, demonstrates quantitative data on structural performance. This comprehensive analysis aims to identify the impact of G code alteration on the finished product. Preliminary experimental results using simple tensile specimens indicate notable improvements in structural performance. Importantly, these improvements are achieved without any discernible mass increase, optimizing material usage and reducing the cost of additive manufacturing. The modified G code targets to strengthen critical areas using updated printing parameters without a net increase in the overall material consumption of the object. This finding holds significant implications for industries reliant on additive manufacturing for load-bearing components, offering a promising avenue for improved efficiency and durability. Integrating advanced techniques, such as G code modification and finite element analysis (FEA), as the additive manufacturing landscape evolves presents a pathway toward optimizing mechanical properties. By contributing valuable insights and laying the groundwork for further exploration and refinement of these methodologies, this study paves the way for enhanced structural performance in various additive manufacturing applications. Ultimately, it encourages innovation and progress in the field, propelling the industry toward new heights of efficiency and reliability.
Elastic and Thermal Properties of Additively Manufactured Continuous Fiber Composites
Authors: Inan Efe E. , Saigal Anil 
Published: January 2025

Abstract
This paper presents a new framework for predicting both elastic and thermal properties of additively manufactured continuous fiber composites as functions of printing parameters. Guided by tensile testing and bespoke thermal conductivity measurements of samples produced by the Markforged Mark Two printer, the framework leverages classical laminate theory (CLT) to offer a convenient and systematic approach to the evaluation of the stiffness and thermal conductivity matrices of 3D printed composite parts.
The thermal conductivity, in particular, of additively manufactured continuous fiber composites is not well documented. Composite materials are highly sought after for applications like electronics packaging, where heat dissipation is an important consideration. The ability to additively manufacture composites for such applications presents previously unattainable opportunities for prototyping for these use cases. Using this framework, important thermal performance metrics like heat dissipation rate can be easily evaluated, allowing for optimizing the printing parameters to better suit the desired application.
Protecting Workers Performing Machine Maintenance: Comparing Modalities
Authors: Hamilton John , Morse John 
Published: January 2025

Abstract
Machine maintenance brings humans into exposure to hazards in unique ways. Modalities to reduce risk vary globally. In the United States the government attempts to protect workers performing maintenance via regulations imposed on employers. The relevant regulation for general industry is titled “The control of hazardous energy (lockout/tagout)”, also known as Lockout/Tagout or LOTO. LOTO relies on training of and compliance by the employees, and enforcement of the LOTO program by the employers. The cost of compliance in time spent can be high and therefore LOTO is sometimes not complied with.
The European Union has a machine directive specifying safety requirements for industrial machines to meet before those machines can be sold. There is no EU regulatory requirement for LOTO like that used in the US. Some maintenance tasks that are legally allowed in Europe without LOTO would be a violation in the US. Whereas in Europe workers can be protected via alternative methods while performing some maintenance tasks, that same maintenance procedure would have to be performed under LOTO in the US to comply with regulations.
Even under the LOTO standard, given the high cost of compliance in some instances, it is reasonably foreseeable to machine designers that LOTO may not be followed. The addition of alternative means of protection through machine design can enhance machine safety whether LOTO is followed.
This paper will explore LOTO and alternative means of protection, compare LOTO and the use of alternative methods, identify strengths and weaknesses of both, and consider case studies regarding LOTO.
Micro-Mechanical Property Evaluation of Heat-Treated Metal 3D Printed Parts Affected by Process Interruptions
Authors: Chigurupati Poojith Chowdary , Dababneh Fadwa , Taheri Hossein , Jones Michael 
Published: January 2025

Abstract
Metal additive manufacturing techniques enable rapid prototyping and on-demand manufacturing while improving supply chain resiliency. Changes in microstructure and micro-mechanical characteristics of 3D printed metal parts occur due to the influence of process interruptions on melting-solidification cycles during the layer evolution in additive manufacturing processes. The process interruption can deteriorate the structural integrity of the 3D printed parts and generate micro-flaws in the interruption region. There are a variety of techniques which can remove or reduce the amount or size of micro-flaws. Manufacturing post-processing techniques such as Heat-Treatment methods can enhance the mechanical properties of the parts. Since variations commonly happen at the layer level, the investigation of mechanical properties must be done such that these variations can be effectively identified, evaluated, and used to inform post-processing needs. Hence, this study investigates the influence of process interruption on the micro-mechanical properties of the metal 3D printed parts for stainless steel parts with and without post-processing. Accordingly, various stainless steel 316L parts are fabricated using powder-bed fusion additive manufacturing process. Manufacturing processes included different process lags. Nano-indentation testing is used to measure the elasticity and hardness. Measurements are recorded in a matrix grid form covering the interruption region of the manufacturing process. Measurement results of measurement are analyzed to detect potential variations caused by the process interruption. To investigate the influence of the post-processing procedures on the enhancements of mechanical properties of the parts, a group of parts were heat-treated in a vacuum furnace. Micro-mechanical properties were also measured for the parts with heat-treated post-processing. Results indicate that process interruptions and lags alter the mechanical properties of the parts; however, the variation can be reduced using post-processing procedures.
Reduced Order Modeling of Flow Over Spanwise Periodic Rough Surfaces
Authors: Huang Yuting , Hutchins Nicholas , McKeon Beverley 
Published: January 2025

Abstract
Resolvent analysis is utilized to model the temporal mean of experimental measurements of a turbulent boundary layer over streamwise aligned, spanwise alternating rough surfaces, where large counter-rotating rolls are observed. Without detailed knowledge of the roughness geometry, the resolvent modes are generated using a smooth wall boundary condition and a spatio-temporal mean extrapolated using an analytical model. A least squares fit is then performed using the resolvent modes on the streamwise time averaged hot wire measurements, achieving good agreement with the experimental results. The spanwise and wall-normal velocity components predicted from the resolvent modes achieves a qualitative agreement with particle image velocimetry (PIV) measurements, correctly predicting the location, shape, and direction of the secondary counter-rotating rolls while under-predicting its magnitude. An eddy-viscosity model is then added into the streamwise momentum equation in the resolvent framework to augment its predictive capabilities, significantly improving the predicted magnitude of the spanwise and wall-normal velocity components. Finally, all three velocity components from the PIV measurement are utilized in the least squares regression, achieving good agreement with the experiments while reducing the degree of freedom to 0.18% of the experimental data. This work showcases the ability to use resolvent modes that can be computed with effectively negligible cost to model flow features unavailable from the experimental data and to efficiently represent experimentally measured flow fields over rough surfaces of industrial interests.
Generation of MATLAB Simscape Models Using Large Language Models for Training Reliability Evaluation Methods
Authors: Hummel Patrick , Grimstad Joachim , Xia Yuchen , Morozov Andrey 
Published: January 2025

Abstract
The approach presented in this paper makes use of the natural language processing capabilities of large language models in order to generate MATLAB Simscape models based on specification texts. This process is based on a well-defined state machine and begins with the creation of abstract system models that may be iterated on using natural language. The abstract models are then converted to more detailed models by adding parameters and blocks required for simulation. Fault tolerance may optionally be improved by automatically applying design patterns that increase redundancy using voter and comparator blocks, among others. The abstract models are then converted into MATLAB Simscape models using traditional algorithms. The generated models can be used to train artificial intelligence systems designed for reliability evaluation. A selection of publicly available large language models is systematically evaluated based on capability regarding this task. A software prototype demonstrates the feasibility of using generative artificial intelligence to assist with the modeling of systems in MATLAB Simscape as a proof-of-concept. Current limitations and future research potential is discussed.
Finite Element Modeling and Additive Manufacturing of High-Density Polyethylene Micro/Nano-Hydroxyapatite Composites for Biomedical Implants
Authors: Al-Kharusi Moosa S. M. , Al Owiemri Mohammed S. , Al Jahwari Farooq K. S. 
Published: January 2025

Abstract
This study examines the development and characterization of High-Density Polyethylene (HDPE) composites enhanced with micro and nano-Hydroxyapatite (HA), aimed at optimizing their utility in biomedical implants through the integration of Finite Element Modeling (FEM) and additive manufacturing techniques. Initial fabrication utilized a twin-screw extrusion process to create a variety of composite formulations, which were then molded and subjected to comprehensive mechanical testing to assess their suitability for orthopedic applications. These tests revealed that nano-HA particularly enhances the mechanical strength and stiffness of the composites, thus improving their load-bearing capabilities which are crucial for implant success. In parallel, FEM was applied using ANSYS to simulate the behavior of these composites under tensile stress, allowing for the validation of experimental results and adjustment of composite configurations for optimal performance.
Further exploration involved the application of additive manufacturing techniques to produce complex implant geometries using the extruded HDPE/HA filaments. This method demonstrated the potential of tailored therapeutic solutions, catering to individual patient needs and advancing the state of custom implant design. The adaptability of HDPE/HA composites to 3D printing underscores their significant role in facilitating the production of durable, precise, and patient-specific implant structures. Through iterative testing and simulation, the study not only confirmed the mechanical enhancements provided by HA fillers but also optimized the processing conditions for effective 3D printing of biomedical implants.
Conclusively, this research highlights the synergy between advanced computational modeling and novel manufacturing processes in the creation of next-generation biomedical implants. The dual approach of FEM and 3D printing allows for the meticulous refinement of material properties and implant designs, presenting a significant advancement in the field of reconstructive surgery. By providing enhanced material solutions that offer both superior performance under physiological conditions and customization capabilities, this study contributes to the broader efforts to improve patient outcomes in orthopedic applications.
Design and Development of Inertially Excited Fully Compliant Robot
Authors: Lozano Raul , Walker Britt , Tekes Ayse 
Published: January 2025

Abstract
Compliant mechanisms, or flexible machines, deform largely under an external force, displacement, torque, or excitation and mimic motions commonly observed in nature. Due to their unique characteristics, such as the ability to be manufactured as a single piece, no friction between neighboring parts, no backlash, and thus enhanced performance, they are widely used in robot design. In this study, we developed a fully compliant locomotive robot consisting of a top plate, four masses, a rail, four links, support structures, initially preloaded compliant beams, and a disk. Two carts (masses) slide along the rail, with one end of the legs connected to each cart via a small length-flexure hinge, and the other ends converging at the center through a flexure hinge. The initially preloaded compliant beams are vertically attached between the top and bottom masses on each side. Engineers typically design active or passive vibration isolators to dampen undesired vibrations caused by unbalanced masses in a rotating system. However, in our design, we utilized the undesired vibrations to inertially excite the robot. A DC motor, positioned within the support structure and connected to the disk, allows for the addition of small loads to the rotating disk with eccentricity, creating controllable vibrations in amplitude and frequency. While the preloaded beams maintain the robot’s vertical position, they also act as compression springs, facilitating motion transfer. We developed the mathematical model of the locomotive robot using Lagrange equations and analyzed the motion in MATLAB Simulink.
LH2 Tanks in Fire Incidents - the Cryogenic High Temperature Thermal Vacuum Chamber Enables In-Depth Insights
Authors: Eberwein Robert , Scarponi Giordano Emrys , Cozzani Valerio , Otremba Frank 
Published: January 2025

Abstract
Liquefied Hydrogen (LH2) and Liquefied Natural Gas (LNG) establish themselves as important energy carriers in the transport sector. Their storage requires tanks with thermal super-insulations to keep them at cryogenic conditions for a long time. These insulation systems have proven itself in various applications over a long time. However, these insulations are still new in land transportation, where accidents involving collisions, fires, and their combination are to be expected. This study summarizes the results of the ongoing research program in which insulations commonly used in industry were analysed through experimental and numerical studies under fire-like conditions. It was found that there are strong differences among the various insulation systems. Several safety concerns and research gaps exists for layered insulations, which are typically used in land transport. To further analyse these insulation systems, a new test concept called Cryogenic High Temperature Thermal Vacuum Chamber (CHTTVC) was developed and manufactured. This concept enables the testing of large insulation samples under industrial conditions and the consideration of cryogenic conditions relevant for the investigation of various phenomena. The results are important for the evaluation of accident scenarios, the improvement of thermal super-insulations, and the development of emergency measures.
Hybrid Thermal Management Method of Li-Ion Batteries Using Heat Pipes and PCM for Electric Vehicles
Authors: Sharifi Nourouddin , Millard Christian , Etufugh Ugochukwu , Shabgard Hamidreza 
Published: January 2025

Abstract
This study presents an experimental investigation into a new hybrid cooling method for 18650 lithium-ion batteries utilized in electric vehicles (EV). The experimental setup comprises a heating section, a phase change material (PCM) reservoir, and a cooling section. The heating section replicates the heat generated by the batteries and includes two cylindrical aluminum housings (with dimensions matching those of an 18650 battery), two cartridge heaters, and an aluminum heat sink. The PCM reservoir is constructed using 3D-printed PLA components. A designated airflow channel is designed for the cooling section. Three copper-water heat pipes (HPs) are utilized to transfer heat from the heaters to the air flow channel through the aluminum housings, the heat sink, and the PCM reservoir. Aluminum fin jackets are affixed to the HPs within the PCM reservoir and the airflow channel to improve heat transfer. Two cooling scenarios — with and without PCM — are investigated. Temperatures at various locations within the setup are measured and compared under multiple power settings of the heat cartridge and air velocities. It was found that for a moderate total power of 16W, the steady-state battery temperatures are reduced by about 14%, 10%, and 4% when using the PCM compared to the case without the PCM for air velocities of 2 m/s, 3 m/s, and 4 m/s, respectively.