bluuebunny/crossref_metadata_2025_split huggingface dataset:
Investigating the Relationship Between Geometric Features and Inspectability of Additive Manufactured (AM) Parts
Authors: Roy Debrina , Srbinovich Tanner , Arguelles Andrea P. , Menold Jessica 
Published: November 2022

Abstract
The versatility of Additive Manufacturing (AM) has enabled engineers and designers to realize previously impossible geometries. However, the increasing geometric complexities of these components pose a significant challenge for traditional inspection methods. If a part cannot be appropriately inspected costly redesign will be required, or worse fatal flaws and imperfections may not be identified prior to part-use. Considering the constraints of inspection techniques early in the design process could help designers make better design decisions. This paper aims to identify and investigate the fundamental relationship between the geometric features, geometric complexity, and overall inspectability of AM parts. Results suggest that traditionally accepted indicators of geometric complexity, such as lattice structures, do not significantly predict part inspectability.
A Local Constraint Resolution Approach for Dynamics Modeling of Parallel Kinematic Manipulators With Single-Loop Complex Limbs
Authors: Müller Andreas 
Published: November 2022

Abstract
A large class of parallel kinematic manipulators (PKM) possess complex limbs, i.e. limbs that comprise kinematic loops. This paper addresses the modeling of PKM with complex limbs with a single closed loops. The best known representative is the Delta robot. A systematic approach to the kinematics and dynamics modeling has been proposed recently. The remaining open issue was the computationally efficient solution of the geometric loop constraints. This is particularly important for model-based control of PKM. Global solution of the overall system of constraints is not efficient. In this paper, a local constraint resolution is introduced. A nested iteration scheme is applied for the local constraint resolution. This implements a constraint embedding technique, as a special case of the general concept known for multibody systems. Among others, one advantage is that the method allows dealing with redundant constraints locally or may even avoid them. As an example, the method is applied to the well-known Delta robot. This PKM is modeled as a 3R[2UU] PKM, which is known to be overconstrained. It is shown that the local constraint embedding can deal with this redundancy.
Parametric Analysis of the Nonlinear Dynamics of Cracked Cantilever Beams
Authors: Hsu Chia-Ling , Tien Meng-Hsuan 
Published: November 2022

Abstract
Structural damage occurs in a variety of civil, mechanical, and aerospace engineering systems, and it is critical to identify the damage at its early stage to prevent from catastrophic failures. When cracks are present in a structure, the breathing phenomenon between the crack surfaces typically triggers nonlinearity in the dynamic response. In order to thoroughly understand the nonlinear effect of cracks on the structural dynamics, two modeling approaches are integrated together in this work to investigate the crack-induced nonlinear response of a cantilever beam. First, a modeling method referred to as the discrete element (DE) method is employed to construct the discrete model of the cracked beam. The model constructed using DE is able to characterize the breathing phenomenon of the crack. Next, a simulation technique referred to as the hybrid symbolic-numeric computational (HSNC) method is then used to analyze the nonlinear response of the cracked beam. The HSNC method provides an efficient way to evaluate both stationary and non-stationary dynamics of the cracked system since it combines the efficient linear techniques and optimization tool to capture the system’s response. The proposed computational platform enables efficient multi-parametric analysis of cracked structures. The effects of crack location, crack depth, and excitation frequency on the cantilever beam are parametrically investigated using the proposed method. Nonlinear features such as the sub-harmonic resonance, non-stationary motion, multi-stability, and frequency shift are discussed in this paper.
Multibody Model Simplification by Parameter Reduction
Authors: Ros Javier , Plaza Aitor , Fuentes Jose D. , Iriarte Xabier 
Published: November 2022

Abstract
Model selection methods are used in different scientific contexts to represent a characteristic data set in terms of a reduced number of parameters. Apparently, these methods have not found their way in the multibody systems dynamics literature. Multibody models can be considered parametric models in terms of their dynamic parameters and model selection techniques can then be used to express these models in terms of a reduced number of parameters. These parameter-reduced models are expected to have a computational complexity smaller than the original one, and still preserve the desired level of accuracy. They are also known to be good candidates for parameter estimation purposes. In this work, simulations of the actual model are used to define a data set representative of the standard working conditions of the system. A parameter-reduced model is chosen and its parameter values estimated so that they minimize a prediction error on these data. To that end, model selection heuristics as well as normalized error measures are proposed. Using this methodology two multibody systems with very different characteristic mobility are analyzed. Very important reductions in the number of parameters and in the computational cost are obtained without compromising too much on the reduced model accuracy. As an aside result, a generalization of the base parameter concept to the context of parameter-reduced models is proposed.
Design of a Single-Input Morphing Compliant Mechanism With Separate Gripping and Retraction Modes
Authors: McGowan Patrick , Hao Guangbo 
Published: November 2022

Abstract
A key aspect of robotics and automation is continuous repetition of predefined travel and actions. One such example is a robotic gripper, gripping an object and displacing it linearly. Compliant mechanisms are designed to replicate the motion of rigid mechanisms through the use of flexible beam elements that take advantage of the elastic deformation properties of a material. Arrangements of compliant beams can be used to successfully transmit or transform purposeful motion and force. In this paper a compliant gripper is proposed that grips an object (X displacement) and retracts it linearly (Y displacement) based on a single actuation. The design is comprehensively analyzed through finite element analysis (FEA) method and is optimized using the design exploration tools. The mechanism is firstly designed by the Rigid Body Replacement method and is based on the double slider mechanism. Morphing is successfully achieved through the use of contact aided features and a pseudo spring beam to decouple the X and Y displacements. The design is refined and optimized using commercial finite element analysis software to closely match an ideal X and Y displacement path and displacement activated transition from X displacement to Y displacement whilst minimizing the input actuation force. Experimental tests are to be conducted to validate the design.
Universal Design Analysis for Improving the Usability of Fused Filament Fabrication 3D Printers
Authors: Grey Rebecca , Sinha Swapnil , de Vries Charlotte Marr 
Published: November 2022

Abstract
To accommodate a variety of users with the growing popularity of 3D printing technology, the concept of usability; the effectiveness of a user’s interaction with the product, must be considered. A seamless user interaction with the currently available commercial 3D printer systems assumes that the users have the required hand strength, ability to stand, and vision, which could be challenging for some learning this new technology. This research intends to utilize the principles of universal design, i.e., the idea of appealing design for all age groups or abilities towards operating the physical 3D printer in order to expand its field of use. Physical challenges of the human body as it moves to interact with desktop fused filament fabrication (FFF) 3D printers were investigated. Following that, a survey was collected, to understand the perspective of 3D printer users in terms of challenges faced while interacting with the machine and troubleshooting them. The survey indicated that users found print bed levelling the most challenging task. As a result, the redesign process for print bed leveling was initiated by the development of design specifications. This paper attempts to shed light on potential improvements that can be made in commercially available desktop systems by implementing universal design guidelines, such that the technology is accessible to a larger population. The process used in this paper is applicable for redesign of any existing product for Universal Design.
Dynamics of a Nonlinear Absorber and Hand-Held Impact Machine
Authors: Alabi Oreoluwa , Gupta Sunit Kumar , Barry Oumar 
Published: November 2022

Abstract
Due to the severity of vibrations transmitted to a worker’s hand through hand-help impact machines (HHIM), workers often suffer from hand-arm vibration syndrome (HAVS). Symptoms of HAVS include vibration white fingers, finger numbness, impaired tactile function, and muscle fatigue. To attenuate the level of transmitted vibrations and, hence, reduce the severity of HAVS, a method of using a nonlinear vibration absorber inerter (NVAI) has been proposed recently. It was observed that the use of NVAI can significantly reduce the transmitted vibration. However, a detailed nonlinear analysis of the HHIM with NVAI has not been performed, which can further help in the optimum design of the NVAI. This is the focus of the current work. The hand-arm system (HAS) coupled to an HHIM with an NVAI is modeled using a lumped parameter model. A detailed nonlinear analysis is performed numerically. A parametric study is performed to explore the effects of different system parameters on the system dynamic and identify key design parameters of the NVAI. We observe that the system exhibits quasi-periodic and periodic motion, which is further confirmed by Poincare maps and Phase portraits. It is further revealed that a careful selection of the absorber properties can significantly reduce harmful vibrations.
Design-Engineers’ Selection of Agency: Harm Mitigation in Ambient Intelligent Environments
Authors: Ballestas Caseysimone , Kim Euiyoung , Lanoy Jesuël , Janssens Jules 
Published: November 2022

Abstract
The computing paradigm where sensor and actuator technology work in tandem to track and act on events in real Euclidean space, known as ambient intelligence (AmI), is likely to become increasingly common due to the rapid maturation of computing technology. Installing AmI in the built environment creates ambient intelligent environments (AmIE), which strive to make the places we inhabit (invisibly) sensitive and responsive to our presence, needs, wants, and preferences. Given that built environments and the goings-on therein are complicated in an of them selves, implementing AmI for (increasingly) complicated tasks in (increasingly) complicated scenarios, increases the difficulty of managing the outcomes in AmIEs. Our previous research indicates that industry practitioners attribute the agency of AmI artifacts as responsible for these outcomes; especially when harm perpetuation is (one of) the outcome(s), which we codified as the Agency/Intelligence Axis [1]. Due to the nascence of AmI, research on best practices for the design-engineering of AmI is still emerging. This research seeks to add to this literature by evaluating our formerly identified Agency/Intelligence Axis in the context of AmIE through a case study of VyZee, a retail company working on transitioning their retail stores to “smart” stores. Our findings highlight that while VyZee seems largely unaware of any relationship between agency and perpetuating un-anticipated/-desired outcomes, they do implement an array of levels of AmI agency in their retail stores, and their justifications for their choices are presented in the discussion. Finally, coding the data revealed more nuance then previously documented in the Agency/Intelligence Axis, and a new Ambient Intelligent Agent Model, which suggests that AmI agents have six properties, is proposed.
Latent Variable Representations for Interactive Structural Design Exploration
Authors: Valdez Sofia , Rodriguez Nicholas , Seepersad Carolyn 
Published: November 2022

Abstract
Additive manufacturing and topology optimization are complementary technologies that enable unprecedented levels of design freedom for realizing complex structures. This increasing design freedom is accompanied by increasing complexity, such that it can become difficult for either computational algorithms or human designers alone to search these expansive design spaces effectively. Our previous work laid the foundation for an interactive design framework that enables human designers to use their expertise and intuition to guide computational algorithms quickly towards promising solutions. The framework established a latent representation of a library of designs by combining classical topology optimization techniques with a conditional generative adversarial network (cGAN). Our goal is to expand on this framework by creating interactive functionalities that allow users to more efficiently visualize and search an expansive structural design space by manipulating its latent variable representation.
Tradespace Organizational Practices: A Case Study
Authors: Daniels Julia , Wagner John R. , Turner Cameron J. , Gorsich David , Rizzo Denise , Hartman Greg , Agusti Rachel , Skowronska Annette , Castanier Matt , Rapp Stephen H. 
Published: November 2022

Abstract
Tradespace analysis capabilities are critical for organizations either selecting large programmatic efforts or those engaged in providing solutions to major program opportunities. The ability of an organization to effectively use the tradespace in their decision-making process had a substantial impact upon programmatic success. Poorly bounded tradespaces may lead to prototype vehicles (or any other system to be designed) that are ultimately unacceptable due to performance, cost, or technical risk issues. Tradespaces that are over-constrained can unduly limit design options and lead to stagnant designs that are unable to incorporate technical innovations. Most organizations find that tradespace analysis presents numerous challenges, so this research aims to address the evaluation of strengths, weaknesses, and opportunities for improvement within an organization. In this study, we explain how an interview-based process was used to perform this analysis and make recommendations for opportunities for process improvement within an organization (Ground Vehicle Systems Center or GVSC). Similar approaches could be applied to other organizations to facilitate the development of an organizational self-assessment that can aid in the identification of internal strengths, weaknesses, and opportunities for improvement within organizations performing tradespace activities.
Design of a Bed Rotation Mechanism to Facilitate In-Situ Photogrammetric Reconstruction of Printed Parts
Authors: Roberts Travis A. , Karmakar Sourabh , Turner Cameron J. 
Published: November 2022

Abstract
Additive manufacturing, or 3D printing, is a complex process that creates free-form geometric objects by sequentially placing material to construct an object, usually in a layer-by-layer process. One of the most widely used methods is Fused Deposition Modeling (FDM). FDM is used in many of the consumer-grade polymer 3D printers available today. While consumer grade machines are cheap and plentiful, they lack many of the features desired in a machine used for research purposes and are often closed-source platforms. Commercial-grade models are more expensive and are also usually closed-source platforms that do not offer flexibility for modifications often needed for research. The authors designed and fabricated a machine to be used as a test bed for research in the field of polymer FDM processes. The goal was to create a platform that tightly controls and/or monitors the FDM build parameters so that experiments can be repeated with a known accuracy. The platform offers closed loop position feedback, control of the hot end and bed temperature, and monitoring of environment temperature and humidity. Additionally, the platform is equipped with cameras and a mechanism for in-situ photogrammetry, creating a geometric record of the print throughout the printing process. Through photogrammetry, backtracking and linking of process parameters to observable geometric defects can be achieved. This paper focuses on the design of a novel mechanism for spinning the heated bed to allow for photogrammetric reconstruction of the printed part using a minimal number of cameras, as implemented on this platform.
Analysis of a Nonlinear Locally Resonant Metamaterial With Resistance-Inductance Shunt
Authors: Malla Arun , Bukhari Mohammad , Barry Oumar 
Published: November 2022

Abstract
The study of metamaterials for simultaneous vibration control and energy harvesting is a subject with considerable recent interest. This paper investigates a weakly nonlinear meta-material with electromechanical local resonators coupled to a resistance-inductance shunt circuit, a system with no previous examination in the literature. The nonlinear band structure of the system is presented to demonstrate the effect of an inductor in the shunt circuit, including the influence on softening and hardening nonlinearity effects. The system is then excited by a transient wavepacket and simulated numerically to further explore the features of nonlinear wave propagation in the proposed structure for multiple inductance values. Particularly, the system’s voltage response is studied through spatial profiles to observe the effects of shunt inductance, nonlinearity, and any potential interaction between the two. Focus is given to the potential for vibration control and energy harvesting by this metamaterial, including comparisons to previously investigated similar systems with resistance-only shunt circuit. For certain parameters including high electromechanical coupling, the band structure of this system is shown to include three mode branches instead of the two-mode band structure observed in the absence of shunted inductor. Strong vibration attenuation is observed in the frequency range around the central mode branch. The effects of the inductor on wave propagation and harvested voltage are also shown.
X-Ray Marching for the Computational Modeling of Tomographic Systems Applied to Materials Applications
Authors: Steuben John C. , Graber Benjamin D. , Iliopoulos Athanasios P. , Michopoulos John G. 
Published: November 2022

Abstract
X-ray tomography (XCT) and microtomography (uCT) are powerful experimental techniques for determining the internal structure of materials and objects. However, the physics governing these systems, particularly the myriad of complex interactions between X-rays and materials, lead to the frequent generation of spurious data “artifacts.” When these techniques are used to determine the quantitatively precise dimensions and morphology of defects and other features present in the objects under study, the presence of these artifacts is highly deleterious. A computational framework for simulating and studying tomographic processes, and the physical origins of such artifacts, may increase the overall utility of these techniques. This work presents the introduction, development, and demonstration of such a framework based on a ray-marching approach. A number of physics-driven and computationally-driven considerations guiding the development of this framework are discussed. A demonstration problem taken from prior literature is examined, and it is shown that even a basic implementation of this framework offers meaningful insight which can be used to improve quantitative measurements made using XCT. We conclude with remarks regarding the usage of this technique in a broader scope, and the work required to approach such tasks.
Towards Characterizing Cognitive Style Coping Behavior in Engineering Design
Authors: Radwan Noriana , Menold Jessica , McTernan Jesse , Jablokow Kathryn , McComb Christopher 
Published: November 2022

Abstract
Problem solving is a crucial aspect of engineering design, and cognitive style, or preferred problem-solving style, is an important way to understand designers’ individual behavior. When there is significant misalignment between the problem frame and one’s cognitive style, it results in cognitive gaps. Large cognitive gaps may hinder effective problem solving. According to Kirton’s adaption-innovation theory, such gaps are managed through coping behavior. However, coping behavior is understudied in the literature, especially when assessing person-problem gaps. We argue that a deeper understanding of these gaps and its resulting coping strategies in problem solving can aid in facilitating effective design. Therefore, the current study was developed to understand how cognitive style and the problem frame impacts solution outcomes; and identify the design strategies and behaviors that are elicited by participants of varying cognitive styles. Through a mixed methods analysis, we found that the problem frame can impact the types of solutions that designers develop and the cognitive experience of their design — where some behaviors indicate the prevalence of coping.
A Boundary-Value Problem for Covariance Analysis of Stochastically Perturbed Limit Cycles
Authors: Ahsan Zaid , Kuehn Christian , Dankowicz Harry 
Published: November 2022

Abstract
In this paper, we discuss an original covariance boundary-value problem that captures the effects of white noise on the local behavior near stable periodic orbits of the corresponding deterministic dynamical systems. The methodology relies on suitably constructed adjoint variables to project the dynamics onto locally transversal hyperplanes and ensure the existence of a unique solution. For each such hyperplane, the computed co-variance matrix describes an approximately Gaussian, stationary distribution that highlights directions of particular sensitivity to noise. In contrast to previous formulations, the boundary-value problem analyzed in this paper makes predictions in the original state-space variables rather than in terms of a reduced set of local coordinates for hyperplanes perpendicular to the local vector field. The formulation is compatible with the general form of an augmented continuation problem for the software package COCO; a non-adaptive version has been implemented as a general-purpose constructor for the periodic-orbit toolbox included in the COCO release. We illustrate the efficacy of the proposed formulation and toolbox by analyzing noise-induced behavior near limit cycles in two examples of nonlinear dynamical systems with autonomous drift terms. The analysis presented in this study can be used to design safe operating regimes for systems working in stochastic environments, as well as to design optimum working conditions for systems utilizing noise, such as energy-harvesting applications.