bluuebunny/crossref_metadata_2025_split huggingface dataset:
Investigation of Planetary Gear Elastic Vibrations Using a Finite Element/Contact Mechanics Formulation
Authors: Cooley Christopher G. , Hood Adrian A. 
Published: November 2023

Abstract
The characteristics of the elastic vibrations for the individual gears used in planetary arrangements are important for predicting noise emissions, analyzing potential failure modes, and detecting damage. This work uses a finite element/contact mechanics planetary gear model to investigate the time and spectral vibration properties of the sun, planet, and ring in a fixed-ring configuration. Ring gears have periodic material point accelerations over a planet-pass cycle. Their spectrum has low frequency components at multiples of the planet-pass frequency and high frequency components that appear in clusters near each mesh frequency harmonic. Each cluster contains vibrations at the mesh frequency and upper and lower sidebands separated by the planet-pass frequency. Because of the ring’s compliance, the sideband components are meaningfully larger than the mesh frequency component, and noticeable asymmetry occurs in their amplitudes. The vibrations of a material point on the rotating sun is periodic with the planet-pass period relative to the sun. Therefore, the sideband frequencies observed on the sun are completely different with those on the ring. The rotating sun’s spectrum has low frequency components at multiples of the planet-pass frequency relative to the sun. Each of its clusters contains the mesh frequency component with sidebands at multiples of the planet-pass frequency relative to the sun. Material points on rotating planet gears have periodicity and sideband behavior related to the planet frequency relative to the carrier. Their spectral content is thus different from both the stationary ring and rotating sun. The spectral vibration features demonstrated in this work could be used by condition indicators to detect damage on the individual gears used in planetary arrangements.
Unlocking Team Success: The Power of Diversity in Engineering Capstone Teams
Authors: Vivekanandan Gopalakrishnan Divyaa , Parkinson Matthew , Mohammed Susan , Miller Scarlett 
Published: November 2023

Abstract
Increasing diversity in engineering is a key priority due to the underrepresentation of women and the role of interdisciplinary teams on engineering success. In light of this, it is vital that we consider how to create inclusive teaming practices where individuals feel safe voicing their opinion and challenging team assumptions. The purpose of this paper was to examine the effect of team diversity (gender and interdisciplinarity) on perceived psychological safety through a study with 66 capstone engineering students. This study found that perceived psychological safety can be predicted by the individual’s gender and the team’s gender composition. Furthermore, results also show that adding information related to major can significantly improve the prediction of individual psychological safety. Finally, this study also explores other factors that might affect an individual’s psychological safety in a team and identifies coordination to be the most influential variable. Moreover, it was found that different groups of people are likely to experience more of or emphasize more on certain critical considerations (namely composition, communication, coordination, cooperation, conflict, cohesiveness, and creativity) when asked to describe positive or negative team interactions that affected their perceived psychological safety depending on their gender and team major composition. Study results show promise for further investigating the effect of different types of diversity and other factors on the psychological safety of individuals in the team.
Mean Time to Failure Prediction for Complex Systems With Adaptive Surrogate Modeling
Authors: Wu Hao , Xu Yanwen , Liu Zheng , Wang Pingfeng 
Published: November 2023

Abstract
The Mean Time to Failure (MTTF) is a critical metric for assessing the reliability of non-repairable systems, and it plays a significant role in incident management. However, accurately estimating MTTF can be challenging due to the limited availability and quality of historical experimental data on a group of identical parts or systems. To address this challenge, we propose an adaptive surrogate modeling method, which approximate the system’s performance functions with a more computationally efficient model to predict the MTTF during the design stage. In this paper, we develop an adaptive Gaussian process (GP) approach that combines with Monte Carlo simulation (MCS) to predict MTTF. The proposed method initially trains a GP model for the system’s performance function, and then an MTTF surrogate model can be obtained. With a learning function, these models are updated dynamically based on new information as it becomes available. We demonstrate the effectiveness of our method on series system, parallel system, and mixed system with two examples, and the results show that the adaptive surrogate modeling method can accurately predict the MTTF of the system. Our method has the potential to improve the reliability and safety of complex system and reduces the need for costly performance testing.
Modeling and Analysis of a Thin Plate With Multiple Harmonic Excitations for Vibrotactile Touch Display Applications
Authors: Rajkumar Santosh Mohan , Singh Kumar Vikram , Koo Jeong-Hoi , Yang Tae-Heon 
Published: November 2023

Abstract
Touchscreen devices have become increasingly common in our daily lives. Although smaller touchscreen devices provide sufficient user interaction with meaningful tactile feedback, larger touch devices have the potential to offer a range of tactile stimulation. Previous research on large touch surface vibrotactile localization has utilized numerous actuators and traditional rigid boundary conditions. However, the possibility of localized haptic rendering using multi-frequency excitations is not explored for large rectangular touch surfaces. This study focuses on developing a finite element model of a large touch surface along with a limited number of electrostatic vibration actuators placed at different spatial locations and analyzing the vibrotactile response produced by various combinations of actuators with different frequencies and amplitudes. The effect of the number of actuators and their placement for rendering haptic feedback on the touch surface is explored. Statistical analysis is presented using model simulations to find out a suitable way of actuator placement which is otherwise cumbersome when chosen arbitrarily on a practical device. The effect of the mechanical property of the actuators on the haptic rendering is also explored. Finally, the possibility of localized haptic rendering by switching between actuator frequencies and actuation positions on the touch surface is demonstrated.
Exploring the Role of Individual Differences in System Interpretation
Authors: Patel Apurva R. , Murphy Alexander R. , Summers Joshua D. , Sen Chiradeep 
Published: November 2023

Abstract
This paper presents a study that explores whether individual differences of engineering design self-efficacy and Need for Closure relate to cluster formation for a systems clustering design task. A simplified nine-item engineering design self-efficacy measure was used. A fifteen item need for closure instrument was used. Systems thinking, as related to the size of the clusters created to plan for fault detection of consumer products, is tested using through products and three different modeling representations. Participants (147) from two universities completed three clustering activities. Each participant was given three models for three products. The models included representations of component graphs, function graphs, and function structures. No significant differences were found between university, gender, academic classification, or first language for the size of clusters. Further, neither engineering design self-efficacy or need for closure were shown to be correlated to the results of the design activity. A significant limitation of the study was that the products were of similar size and complexity, meaning that the differentiation between the cluster sizes was limited in scope. Additionally, the student participant population was drawn from first year courses at the two universities. Future work is suggested to include additional individual differences, using more advanced participants, and expanding the scope of the products in the testing. The structure of this experiment can serve as the basis for future studies on the influence of individual difference measures on systems thinking and clustering activities.
Design of a Data Fusion and Deep Transfer Learning Test Rig for Roller Bearings Diagnosis and Prognosis
Authors: Sehri Mert , Dumond Patrick , Bouchard Michel 
Published: November 2023

Abstract
Although they are crucial parts of heavy machinery, bearings are also prone to failure; between 50 and 60 percent of rotating machinery failures are caused by bearings. Data is gathered for the diagnosis and prognosis of bearing faults to help remedy this. Diagnosis relates to identifying a fault situation using recognized symptoms, whereas prognosis focuses on forecasting how the fault will turn out. To determine the states of machines, machine learning techniques are utilized. Deep learning is a branch of machine learning that focuses on training neural networks with several layers. Traditional (shallow) learning, which uses pre-defined features in data to identify machine conditions, and deep learning, which employs complex data types, are two methods of machine learning. In recent years, data fusion and transfer learning have become interesting and important subfields of deep learning. Transfer learning uses previously trained models as a starting point for new tasks by applying learned knowledge from the previous task on the related new task, whereas data fusion mixes many data types to improve comprehension. In this study, the need for large quantities of data fusion and transfer learning data is used to design a test rig for roller bearing fault identification and prognosis. Historically, academic researchers have concentrated on using the data they have gathered with their test rigs to undertake data analysis, rather than concentrating on the design of the test rig itself. Yet, there is a need for a test rig design that appropriately gathers clean multi-sensor data from a variety of bearing sizes to enhance deep machine learning algorithm research for bearing health diagnosis and prognosis via transfer learning. By offering useful methods that can be utilized to perform machine health diagnosis and prognosis on bearings, this work aims to close the gap between the needs of industry and the research community. This can aid in the early detection of faults, offer time frames for repair or replacement, and prevent catastrophic failures.
A Unified Design Equation to Represent Geometric Constraints of Spatial SS, ES and SE Dyads
Authors: Deng Xueting , Purwar Anurag , Ge Qiaode Jeffrey 
Published: November 2023

Abstract
This paper presents a unified design equation for the type and dimensional synthesis of spatial SS, ES and SE dyads for the motion synthesis problems, where S stands for a spherical and E stands for a planar joint. While there has been a lot of research on dimensional synthesis of planar and spherical mechanisms, little work has been done on the type and dimensional synthesis of spatial mechanisms. In this paper, we show that we can derive a single algebraic equation to represent geometric constraints of each of the SS, ES, and SE spatial dyads. While this design equation represents geometric constraints redundantly, explicit mechanical constraints have to be applied to extract the type and dimensional parameters of dyads during synthesis. A two-step algorithm is used to first algebraically fit the given pose constraints of the moving platform and then constraints are applied to obtain type and dimensions. The algebraic fitting is performed using singular value decomposition and candidate sets of solution vectors are obtained. While these candidate vectors are capable of representing any type of spatial dyads, quadratic constraints are applied to obtain mechanical dyads. This paper is an extension of our previous work on type and dimensional synthesis of planar dyads formed with R (Revolute) and P (Prismatic) joints.
An Efficient Surrogate Modeling Method for Reliability-Based Global Path Planning of Off-Road Autonomous Ground Vehicles
Authors: Yin Jianhua , Hu Zhen , Mourelatos Zissimos P. , Gorsich David , Singh Amandeep , Tau Seth 
Published: November 2023

Abstract
The off-road autonomous ground vehicle operation is challenging because of the complex and highly uncertain working environment they operate in. This brings risks to their mission success. Physics-based global path planning combining physics-informed surrogate modeling with path planning is recently employed to address this issue by ensuring a reliability to complete the mission. However, the current two-stage methods require a relatively high computational cost to obtain the reliability map undermining the practicability for real-life applications. To decrease the computational cost, this study proposes an efficient surrogate modeling framework for physics-based path planning under uncertainty. The proposed method couples adaptive surrogate modeling with path planning sequentially through several iterations of path planning and path verification. Instead of obtaining an accurate reliability map for the whole target area in the two-stage approach, the proposed method only refines the map in the vicinity of the path identified, thereby reducing the computational cost. The final path is determined if the path verification is successful; i.e. the specified mission reliability for the path is met. The presented case study demonstrates that the proposed method can significantly reduce the number of surrogate refinement iterations and reduce the computational cost for physics-based path planning.
High-Fidelity Nonlinear Forced Response Analysis of Aero-Engine Turbine Blades With Root Friction Contact
Authors: Tamer Aykut , Schwingshackl Christoph , Jones Adrian 
Published: November 2023

Abstract
In aero-engines, turbines drive compressors and fans by extracting energy from the combusted hot air. For the next generation ultra-high bypass ratio engines, the turbine blades are among the most critical components due to the harsh operating environments. A turbine blade consists of a streamlined aerofoil and the blade root. The root is designed in such a way that it can be inserted into a similar yet marginally bigger slot on the disk. The most common root designs include dovetail and firtree roots. Under normal operation, the blade root is loaded against the slot in the disc by centrifugal forces due to rotation. During operation, blade vibration can lead to microslip in the roots, which generates additional frictional damping and leads to a nonlinear dynamic response. The complex geometry of the blade and its support require high-fidelity finite element analysis to capture the linear dynamic response accurately and detailed frictional interface models to capture the nonlinear response. Therefore, to predict correct amplitude under dynamic loads, friction should be included together with a detailed blade structural dynamics model. This work presents a framework that can combine detailed finite element models with friction models so that a realistic nonlinear dynamic response of the blade can be obtained at representative amplitudes.
Noodle: Design of a Modular, Configurable Serpentine Robot With Series Elastic Actuators and Modular Segment Panels
Authors: Lay Gordon , Pretty Chris , Holder-Pearson Lui 
Published: November 2023

Abstract
This paper outlines and describes the design of Noodle; a modular, reconfigurable, and low-cost serpentine robot. The design is inspired by the diverse set of gaits exhibited by biological snakes, and seeks to provide a universal solution to achieving all of them. However, organic snakes possess varying microscopic ventral scale structures depending on their habitat and gait, which impacts the frictional forward-transverse anisotropy of the ventral scales. To provide a design that will best perform all serpentine gaits, the design proposes modular ventral panels on the sides of the robot’s segments. This acquires the capacity to configure the robot’s ventral contact surface prior to deployment onto a given substrate, and the ability to select its ventral side by rolling and changing orientation. By modularising the ventral contact surface, access to varying degrees of frictional anisotropy is granted, which provides the benefit of selecting the optimal ventral surface for a given gait and/or substrate. Through the inclusion of Series Elastic Actuators, compliance and torque sensory are achieved. Noodle has been designed to accept two types of Series Elastic Elements (SEE): coil-spring and polyurethane. The design, benefits and shortcomings of each SEE type are investigated. Due to these modes of configurability, Noodle can be either configured or be adapted for a given substrate, and provides a basis for implementing active gait adaptation behaviour.
Effects of Soft Contact on the Base of Support of Legged Systems
Authors: Mummolo Carlotta , Duvert Océane , Torres-Pardo Adriana , Rodriguez-Cianca David , Torricelli Diego , Carbone Giuseppe 
Published: November 2023

Abstract
The main balance mechanism in legged systems is the control of the Center of Pressure (COP) over the Base of Support (BOS). The BOS dimensions are therefore strictly related to the control authority of the COP and are typically associated to foot dimensions. This geometrical BOS dimension is valid for the case of ideal rigid flat foot but does not represent the truly available range for COP control, hence the effective BOS, when a compliant foot-ground contact is modeled. This work presents experimental observations on the maximum COP range (i.e., effective BOS) for a subject perturbing its standing balance on rigid and soft grounds. A legged system with a viscoelastic foot contact is modeled to illustrate how a given foot model impacts the effective BOS and can lead to different prediction on the system’s stability, quantified by existing margin of balance. This work motivates the need for novel methodologies for balance and falling prediction, currently focused on ideal rigid feet, in which the effects of a viscoelastic contact on the control of the COP are considered.
Reducing first appointment delays for electron radiotherapy patients by improving the treatment planning pathway: a quality improvement project
Authors: Gately Louise , Sanders Katie , Proudlove Nathan 
Published: November 2023

Clatterbridge Cancer Centre (CCC) is a specialist hospital trust in England with three sites.Delay to the start of an appointment for radiotherapy, especially the first appointment (a ‘New Start’) is poor, both for operational efficiency and patient experience, causing stress for both patients and staff. Our aim is for the New Start to begin within 30 min of the allotted appointment time. To this end, we established another aim: for ‘Final Checks’ to the radiotherapy plan to be completed at least 30 min prior to the New Start appointment time.Prior to this quality improvement (QI) project, only 33% of electron-treatment New Start appointments started within the target 30 min (the average delay was 52.4 min) and only 48% of the corresponding Final Checks had been completed by their 30 min prior target.The treatment pathway for these patients was redesigned, with the aim of 90% of New Start appointments starting within 30 min of the allotted appointment time.By the end of this QI project, 69.2% of New Start appointments started within 30 min of the appointment time (with average delay reduced to 27.2 min), and 92.3% of Final Checks were completed by their 30 min prior target. We also reduced the number of safety (Datix) incidents due to plan not ready from 10 to 0. A year after the project, we have held most of the time improvements and still have had 0 plan-not-ready Datix.The largest improvement was achieved by introducing a proxy (without the patient present) ‘day 0’ appointment. This takes place in advance of the New Start appointment to enable earlier planning. Subsequent improvements included: automating previously manual planning calculations, making the care path consistent with other external beam radiotherapy care paths at CCC to reduce staff cognitive load and sharing key performance data with staff.
Association between Life’s Essential 8 and Cerebral Small Vessel Disease
Authors: Liu Dandan , Cai Xueli , Yang Yingying , Wang Suying , Mei Lerong , Jing Jing , Li Shan , Wang Mengxing , Chen Yun , Meng Xia , Wei Tiemin , Wang Yongjun , Wang Yilong , Pan Yuesong 
Published: November 2023

Background
Given that associations of Life’s Essential 8 (LE8) and cerebral small vessel disease (CSVD) or its imaging markers were unclear, we examined relationship between them.

Methods
The cross-sectional study included community residents from the PolyvasculaR Evaluation for Cognitive Impairment and vaScular Events study. We calculated the total LE8 score, medical LE8 score and behavioural score, and categorised them into low (<60), moderate (60–79) or high (≥80) group. MRI markers included lacunes, white matter hyperintensities (WMH), enlarged perivascular spaces in basal ganglia (BG-EPVS) and cerebral microbleeds (CMB). In respect of, total CSVD score (0–4 points), WMH, lacunes or CMB were categorised as two grades, and BG-EPVS (N>10) was allocated one point. Based on modified total CSVD score (0–6 points), WMH or CMB was modified to three grades, and BG-EPVS (N>20) was allocated one point.

Results
Among 3061 participants in this study, 1424 (46.5%) were male. Higher LE8 score was associated with lower total CSVD score (moderate vs low: cOR 0.78, 95% CI 0.63 to 0.96; high vs low: cOR 0.44, 95% CI 0.33 to 0.59), and the medical score was inversely related to the total CSVD score. Furthermore, the medical score was inversely related to odds of WMH (p<0.05), modified WMH (p<0.05), lacunes (p<0.05) or BG-EPVS (p<0.05), and the behavioural score were inversely related to the odds of lacunes and BG-EPVS.

Conclusions
Higher LE8 score which indicates better cardiovascular status was associated with lower burden of CSVD and its MRI markers. Longitudinal studies are needed to examine the causality.