bluuebunny/crossref_metadata_2025_split huggingface dataset:
Dynamic Simulation of Reeving Systems With the Extension of the Modal Approach in the Axial Direction
Authors: Mohammadi Narges , Escalona José Luis 
Published: November 2021

Abstract
In this work, the simulation of reeving systems has been studied by including axial modes using the Arbitrary Lagrangian-Eulerian (ALE) description. The reeving system is considered as a deformable multibody system in which the rigid bodies are connected by the elastic wire ropes through sheaves and reels. A set of absolute nodal coordinates and modal coordinates is employed to describe the motion and deformation in the axial direction. This new method allows the analysis of elements with non-constant axial strain along its length. In addition, modal coordinates are employed to describe the dynamic motion in the transverse direction. The non-constant axial displacement within the wire rope is computed in terms of the absolute position coordinates, longitudinal material coordinates, and modal deformation coordinates. To derive the governing equations of motion, Lagrange’s equation is employed. The formulation is validated for a simple pendulumlike motion actuated by an initial velocity. The simulation results are provided to trace the movements of the payload. It can be seen that by adding modal coordinates, the axial force within the element changes. Moreover, the effects of modal coordinates in the axial direction are presented for a different number of nodes, and the resulting axial forces are compared with reference solution.
A Fractional-Order Active Disturbance Rejection Controller Design for a PMSM Servo System
Authors: Li Bolin , Chen Pengchong , Luo Ying 
Published: November 2021

Abstract
This paper proposes a fractional-order active disturbance rejection controller (FOADRC) parameters tuning design method for a permanent magnet synchronous motor (PMSM) servo system with frequency-domain analysis of active disturbance rejection control. In this method, a fractional-order proportional derivative (FOPD) and a fractional-order [proportional derivative] (FO[PD]) controllers design combining with active disturbance rejection control (ADRC) are proposed. A systematic parameter tuning scheme is presented, and a flat phase constraint is applied as a design specification, which guarantees the phase is flat around the gain crossover frequency point, and the closed-loop system is robust to gain variations. The simulation results illustrate that the response of the PMSM servo system using FO[PD]-ADRC has a smaller overshoot, less tracking error, and better resistance to load disturbance than that using FOPD-ADRC.
A Framework for Centralizing Ethics in the Design Engineering of Spatial Computing Artifacts
Authors: Ballestas Caseysimone , Chandrasegaran Senthil , Kim Euiyoung 
Published: November 2021

Abstract
Creating Spatial Computing (SComp) artifacts (including Virtual Reality, Augmented Reality, Mixed Reality, and Ambient Intelligent artifacts) is a rapidly-emerging domain in need of new design methodologies. In this paper, we examine whether and how ethics are procedurally integrated into the creations of SComp artifacts. After an introduction to terminology — including a reframed definition of Spatial Computing — findings of interviews with Spatial Computing practitioners are shared. The interviews indicated an awareness among professionals about the inordinate vulnerability of SComp artifacts, and about the need for — and the lack thereof — processes and tests to mitigate negative effects of SComp artifacts. Results from the domain expert interviews are integrated into a proposed framework: The Framework for Ethical Spatial Computing Design Engineering. Our framework serves to support researchers and practitioners in devising new methodologies unique to Spatial Computing by highlighting considerations central to the creation of ethical artifacts. The framework integrates the findings from the in-depth interview study and builds on existing models in Design Process, Methods, and Human-Computer Interaction (HCI) Research that highlight important barriers and opportunities between research and practice. It maps the three-phases journey consisted of (1) Enablers, (2) Synthesizers, and (3) SComp Artifacts. We trust that our work sheds light on considerations necessary to the creation of ethical Spatial Computing artifacts.
The Kinematic and Static Analysis of the Dual Drive Fusiform Tensegrity Robot
Authors: Liu Shibo , Mei Jiangping , Wang Panfeng , Guo Fan 
Published: November 2021

Abstract
In recent decades, researchers have successfully applied tensegrity robots in wilderness exploration, aerospace and biomimicry, based on the strong adaptability and high stiffness to mass ratio. In this paper, a fusiform tensegrity robot driven by cable and telescopic strut is proposed, which is intended to be used as a foot module of a multi-legged robot. The numerical kinematic and static solution of the dual drive fusiform tensegrity robot is derived using the principle of minimum energy. Then, its force space, which is a set of external forces applied to the robot in a certain equilibrium configuration, is calculated. Next, the workspace of one reference point is derived by calculating an equivalent four bar mechanism. Meanwhile the workspace of the other end of the strut is calculated numerically. Finally, the theoretical analysis is verified by a simulation, and the dual drive fusiform tensegrity robot module is proved to be feasible as one foot of a multi-legged robot.
Simulation of Corona Electrostatic Separator for End-of-Life Management in Printed Circuit Boards
Authors: Patil Trunal , Rebaioli Lara , Fassi Irene 
Published: November 2021

Abstract
Printed circuit boards (PCBs) are made of several materials, including platinum, gold, silver, and rare earth elements, which are very valuable from a circular economy perspective. The PCB end of life management starts with the component removal, then the PCBs are shredded into small particles. Eventually, different separation methods are applied to the pulverized material to separate metals and non-metals. The corona electrostatic separation is one of the methods that can be used for this purpose since it is able to separate the conductive and non-conductive materials. However, the lack of knowledge to set the process parameters may affect the efficiency of the corona electrostatic separation process, ultimately resulting in the loss of valuable materials. The simulation of particle trajectory can be very helpful to identify the effective process parameters of the separation process. Thus, in this study, a simulation model to predict the particles trajectories in a belt type corona electrostatic separator is developed with the help of COMSOL Multiphysics and MATLAB software. The model simulates the particle behavior taking into account the electrostatic, gravitational, centrifugal, electric image, and air drag forces. Moreover, the predicted particles trajectories are used to analyze the effects of the roll electrode voltage, angular velocity of roll electrode, and size of the particles on the separation process.
Functionally Graded Non-Periodic Cellular Structure Design Using a Surrogate Model-Based Optimization Scheme
Authors: Wang Jun , Huang Jida 
Published: November 2021

Abstract
Topological tailoring of materials at a micro-scale can achieve a diverse range of extreme physical and mechanical properties. Modification of material properties through customizing the structural pattern paves an avenue for novel functional product design. In this paper, a non-periodic microstructure design framework is explored for functional parts design with high-strength and functional property gradation. To address the common problem of geometric frustration in non-periodic microstructure design, we employ a smooth transition layer to connect distinct structural patterns and thus achieve functional gradation between adjacent microstructures. The concept of spatial control points is introduced for implementing the transition layer. To pursue a superior macro-structural performance for designing objects, we formulate the control point as design variables and encapsulate it into macro-structural design optimization problems. Given that our objective function involves finite element (FE) simulations, a surrogate model-based optimization scheme is utilized to cope with the computational challenge brought by the FE simulation. Experimental results demonstrate that the proposed design framework can yield both functionally graded light-weight structures and high-strength macro-mechanical performance. The compatibility issues in traditional non-periodic microstructure design are addressed. Comparative studies reveal that the proposed framework is robust and can potentially generate desired functional products with spatially varying properties.
Break It Down: Comparing the Effects of Lecture- and Module-Style Design for Additive Manufacturing Educational Interventions on Students’ Learning and Creativity
Authors: Prabhu Rohan , Simpson Timothy W. , Miller Scarlett R. , Meisel Nicholas A. 
Published: November 2021

Abstract
Given the growing presence of additive manufacturing (AM) processes in engineering design and manufacturing, there has emerged an increased interest in introducing AM and design for AM (DfAM) educational interventions in engineering education. Several researchers have proposed AM and DfAM educational interventions; however, some argue that these efforts might not be sufficient to develop higher-level skills among engineers (e.g., identifying design opportunities that leverage AM capabilities). Prior work has shown that longer, distributed educational interventions are more effective in encouraging learning and information retention; however, these interventions could also be time-consuming and expensive to implement. Therefore, there is a need to test the effectiveness of longer, distributed DfAM educational interventions compared to shorter, lecture-style interventions. Our aim in this research is to explore this research gap through an experimental study. Specifically, we compared two variations of a DfAM educational intervention: (1) a module-style intervention spread over two sessions with the introduction of DfAM evaluation metrics, and (2) a lecture-style intervention completed in a single session with no evaluation metrics introduced. From our results, we see that students who received the module-style intervention reported a greater increase in their DfAM self-efficacy. Additionally, students who received the module-style intervention reported having given a greater emphasis on part consolidation and feature size. Finally, we observe that the structure of the educational intervention did not influence the creativity of ideas generated by the participants. These findings highlight the utility of module-style DfAM educational interventions towards increasing DfAM self-efficacy, but not necessarily design creativity. Moreover, these findings highlight the need to formulate educational interventions that are effective and efficient.
Mechanical Characterization of Metal Additively Manufactured Contact Aided Cellular Compliant Mechanisms
Authors: Khurana Jivtesh B. , Frecker Mary 
Published: November 2021

Abstract
Additive manufacturing allows for the creation of complex geometries that can be optimized for performance. However, understanding the effect of the manufacturing process on part performance is essential to balance performance with manufacturability. In this work, a cellular contact aided compliant mechanism previously designed by the authors is manufactured using laser powder bed fusion. Failure modes for C3M lattice design are highlighted and recommendations for manufacturability are obtained. The mechanical response of C3Ms is characterized through compression testing of lattice and single cells. Compression testing is used to understand the mode of energy absorption of C3M lattices and compare with mechanical simulations. Lattices with large wall thickness and largest cell size are found to absorb the most strain energy. The increase in stiffness of the C3M lattice is found to depend on the thickness of the cell walls and size of the contact gap. The failure modes based on manufacturing and mechanical test data are synthesized to generate design rules for selecting C3M geometry to minimize manufacturing defects and maximize performance.
Negative Refractive Index in a Two-Dimensional Nonlinear Rotator Lattice
Authors: Fang Lezheng , Leamy Michael J. 
Published: November 2021

Abstract
Acoustic metamaterials achieving negative index refraction usually operate linearly over a narrowband of frequency and consist of complex unit cell structures incorporating resonators. In this paper, we propose and analyze a simple, non-resonant, nonlinear rotator lattice structure which can be configured with either a positive or negative index of refraction over a broadband frequency range. The system’s frequency-dependent transmission is studied analytically via a reduced model along the interface of positive and negative refractive index lattices. Results for energy transmission are compared to those obtained using direct numerical simulation and close agreement is documented for small amplitude waves. For larger amplitude waves, a multiple scales analysis approach is used to show that the nonlinearity of the lattice shifts the system’s band structure, inducing amplitude-dependent transmission. For the studied system, the transmission decreases as we increase the incident wave amplitude, agreeing qualitatively with results from direct numerical simulation. At large-enough amplitudes, near the interface the wave amplitude decreases rapidly. As the wave travels further into the media, the amplitude drops, causing the nonlinear effect to decline as well. This decaying envelope does not result in a zero transmission in the far field, as expected from linear theory, and instead, the nonlinearity of the proposed rotator lattice prevents the far-field transmitted wave from surpassing a specific threshold amplitude, regardless of the incident wave. This finding may serve as an inspiration for designing nonlinear wave saturators.
When Decomposition Increases Complexity: How Decomposing Introduces New Information Into the Problem Space
Authors: Mukherjee Suparna , Hennig Anthony , Topcu Taylan G. , Szajnfarber Zoe 
Published: November 2021

Abstract
Decomposition is a dominant design strategy because it enables complex problems to be broken up into more manageable modules. However, although it is well known that complex systems are rarely fully decomposable, much of the decomposition literature is framed around reordering or clustering processes that optimize an objective function to yield a module assignment. As illustrated in this study, these approaches overlook the fact that decoupling partially decomposeable modules can require significant additional design work, with associated consequences that introduce considerable information to the design space. This paper draws on detailed empirical evidence from a NASA space robotics field experiment to elaborate mechanisms through which the processes of decomposing can add information and associated descriptive complexity to the problem space. Contrary to widely held expectations, we show that complexity can increase substantially when natural system modules are fully decoupled from one another to support parallel design. We explain this phenomenon through two mechanisms: interface creation and functional allocation. These findings have implications for the ongoing discussion of optimal module identification as part of the decomposition process. We contend that the sometimes-significant costs of later stages of design decomposition are not adequately considered in existing methods. With this work we lay a foundation for valuing these performance, schedule and complexity costs earlier in the decomposition process.
Dwelling on the Connection Between SO(3) and Rotation Matrices in Rigid Multibody Dynamics – Part 1: Description of an Index-3 DAE Solution Approach
Authors: Taves Jay , Kissel Alexandra , Negrut Dan 
Published: November 2021

Abstract
In rigid multibody dynamics simulation using absolute coordinates, a choice must be made in relation to how to keep track of the attitude of a body in 3D motion. The commonly used choices of Euler angles and Euler parameters each have drawbacks, e.g., singularities, and carrying along extra normalization constraint equations, respectively. This contribution revisits an approach that works directly with the orientation matrix and thus eschews the need for generalized coordinates used at each time step to produce the orientation matrix A. The approach is informed by the fact that rotation matrices belong to the SO(3) Lie matrix group. The numerical solution of the dynamics problem is anchored by an implicit first order integration method that discretizes, without index reduction, the index 3 Differential Algebraic Equations (DAEs) of multibody dynamics. The approach handles closed loops and arbitrary collections of joints. Our main contribution is the outlining of a systematic way for computing the first order variations of both the constraint equations and the reaction forces associated with arbitrary joints. These first order variations in turn anchor a Newton method that is used to solve both the Kinematics and Dynamics problems. The salient observation is that one can express the first order variation of kinematic quantities that enter the kinematic constraint equations, constraint forces, external forces, etc., in terms of Euler infinitesimal rotation vectors. This opens the door to a systematic approach to formulating a Newton method that provides at each iteration an orthonormal rotation matrix A. The Newton step calls for repeatedly solving linear systems of the form Gδ = e, yet evaluating the iteration matrix G and residuals e is inexpensive, to the point where in the Part 2 companion contribution the proposed formulation is shown to be two times faster for Kinematics and Dynamics analysis when compared to the Euler parameter and Euler angle approaches in conjunction with a set of four mechanisms.
An Introduction to 3D SPI2 (Spatial Packaging of Interconnected Systems With Physics Interactions) Design Problems: A Review of Related Work, Existing Gaps, Challenges, and Opportunities
Authors: Peddada Satya R. T. , Zeidner Lawrence E. , James Kai A. , Allison James T. 
Published: November 2021

Abstract
Optimal 3D spatial packaging of interconnected systems with physical interactions (thermal, hydraulic, electromagnetic, etc.), or SPI2, plays a vital role in the functionality, operation, energy usage, and life cycle of practically all engineered systems, from 3D chips to ships to aircraft. These highly-nonlinear SPI2 problems, involving tightly constrained component packing, governed by coupled physical phenomena transferring energy and material through intricate geometric interconnects, have largely resisted design automation for decades, and can quickly exceed human cognitive abilities at even moderate complexity levels. Existing design methods treat the pieces of this problem separately without a fundamental systems approach and are sometimes too slow to evaluate various possible designs. Hence, there exists an emergent need to develop efficient SPI2 design automation frameworks for two reasons: 1) to enable the rapid generation and evaluation of candidate SPI2 design solutions; and 2) for the development of newer complex engineering systems. In this paper, the holistic 3D-SPI2 design problem with its attributes is defined, previous research efforts in various individual SPI2 related areas are reviewed, some existing critical gaps are outlined, and associated challenges are identified. Finally, a vision for fundamental research in SPI2 design based on the authors’ experience in this topic is presented through a set of new exciting opportunities at the intersection of several engineering domains.
Preliminary Study on Multibody Modeling and Simulation of an Underactuated Gripper With Differential Transmission
Authors: Achilli Gabriele Maria , Logozzo Silvia , Valigi Maria Cristina , Malvezzi Monica 
Published: November 2021

Abstract
Robotic grippers have represented a challenge for designers and engineers since at least three decades, due to the complexity of grasping and manipulation tasks. Underactuated and soft robotic grippers are a technology that allows good dexterity and manipulating capabilities, by reducing the number of actuators. However, this type of device requires the use of complex mechanical systems to compensate the underactuated implementation limits, such as differential mechanisms. The differential mechanism is necessary to decouple finger closures and distribute forces.
The multibody simulation allows to evaluate the main parameters of the elements to understand how the differential system can work. The development and design of complex mechanical systems is simplified by this technique.
In particular, this paper presents a multibody simulation analysis which recreates an elementary model of a gripper with two links and a single actuator; the developed model reproduces the grasping of an object using a mechanical differential pulley system, placed beneath the fingers. Some results are presented to study the role of the differential when the fingers grasp an object with different configurations.
The aim of this work is to show how an accurate and still manageable multibody model integrated in Matlab environment is able to extend the classical grasp metrics to a more general dynamic setup.
On a Class of Polar Log-Aesthetic Curves
Authors: Parque Victor 
Published: November 2021

Abstract
Curves are essential concepts that enable compounded aesthetic curves, e.g., to assemble complex silhouettes, match a specific curvature profile in industrial design, and construct smooth, comfortable, and safe trajectories in vehicle-robot navigation systems. New mechanisms able to encode, generate, evaluate, and deform aesthetic curves are expected to improve the throughput and the quality of industrial design. In recent years, the study of (log) aesthetic curves have attracted the community’s attention due to its ubiquity in natural phenomena such as bird eggs, butterfly wings, falcon flights, and manufactured products such as Japanese swords and automobiles.
A (log) aesthetic curve renders a logarithmic curvature graph approximated by a straight line, and polar aesthetic curves enable to mode user-defined dynamics of the polar tangential angle in the polar coordinate system. As such, the curvature profile often becomes a by-product of the tangential angle.
In this paper, we extend the concept of polar aesthetic curves and establish the analytical formulations to construct aesthetic curves with user-defined criteria. In particular, we propose the closed-form analytic characterizations of polar log-aesthetic curves meeting user-defined criteria of curvature profiles and dynamics of polar tangential angles. We present numerical examples portraying the feasibility of rendering the logarithmic curvature graphs represented by a straight line. Our approach enables the seamless characterization of aesthetic curves in the polar co-ordinate system, which can model aesthetic shapes with desirable aesthetic curvature profiles.