bluuebunny/crossref_metadata_2025_split huggingface dataset:
A Real-Time, Interactive Method for Fast Modification of Large-Scale CAE Mesh Models
Authors: Chen Yifan , Stewart Paul , Buttolo Pietro , Ren Feng 
Published: December 2020

Abstract
An interactive mesh manipulation method is presented. Utilizing a Direct Surface Manipulation technique, the tool allows the user to define a specific region on an existing mesh model and modify the vertices within this region. Specific mathematical functions are applied to allow direct, precise, and coordinated modification of the vertices. The method was implemented on a prototype interactive graphics system and has demonstrated the capability to allow quick modification of large-scale automotive CAE models. One important benefit of the tool is to significantly shorten the time needed to perform CAE-based Design of Experiments (DoE), where a series of slightly different CAE mesh models must be generated in search for optimum design parameters.
Tube Production and Assembly Systems: The Impact of Compliance and Variability on Yield
Authors: Wei Yu-Feng , Thornton Anna C. 
Published: December 2020

Abstract
Variation modeling is used in design to predict and diagnose potential quality problems. Most variation modeling assumes the parts are rigidly assembled. However, in some cases, this assumption is invalid. For example, when hydraulic tubes are assembled into aircraft structures, the compliance of the tube facilitates assembly. If the tubes were rigid, they cannot be assembled, i.e., the variations of the tubes and structures are too great. Despite the importance of compliance in assembly, it is typically not explicitly modeled during design. This paper proposes a new method to directly predict the assemblability of any tube design with minimal dependence CAD/FEM modeling and simulation. The model includes a variation model for the tubes and aircraft, compliance model and assembly model. It can be used during design to improve yields.
Algorithms for Design and Interrogation of Functionally Gradient Material Objects
Authors: Liu Hongye , Cho Wonjoon , Jackson Todd R. , Patrikalakis Nicholas M. , Sachs Emanuel M. 
Published: December 2020

Abstract
Solid Freeform Fabrication (SFF) processes have demonstrated the ability to produce parts with locally controlled composition. In the limit, processes such as Three-Dimensional Printing(3DP) can create parts with composition to the length scale of 100 μm. To exploit this potential, new methods for automatic design of Functionally Gradient Material (FGM) parts need to be developed. This paper presents an efficient method for design and composition interrogation of FGM solids. The design tool based on the distance function from the surface of the part requires enhanced efficiency, and so does the interrogation of the part. The approach for improving efficiency includes preprocessing the model with bucket sorting and 3D digital distance transform, and an efficient point classification algorithm. Based on these tools, an efficient algorithm for distance function computation is developed for the design of FGM through distance to the surface of the part or distance to an .STL surface boundary. An efficient algorithm to evaluate composition at a point, along a ray or on a plane is also presented.
A Hybrid Genetic-Direct Search Algorithm for the Shape Optimization of Solid C-Frame Cross-Sections
Authors: Nassef Ashraf O. , Hegazi Hesham A. , Metwalli Sayed M. 
Published: December 2020

Abstract
The hybridization of different optimization methods have been used to find the optimum solution of design problems. While random search techniques, such as genetic algorithms and simulated annealing, have a high probability of achieving global optimality, they usually arrive at a near optimal solution due to their random nature. On the other hand direct search methods are efficient optimization techniques but linger in local minima if the objective function is multi-modal. This paper presents the optimization of C-frame cross-section using a hybrid optimization algorithm. Real coded genetic algorithms are used as a random search method, while Nelder-Mead is used as a direct search method, where the result of the genetic algorithm search is used as the starting point of direct search. Traditionally, the cross-section of C-frame belonged to a set of primitive shapes, which included I, T, trapezoidal, circular and rectangular sections. The cross-sectional shape is represented by a non-uniform rational B-Splines (NURBS) in order to give it a kind of shape flexibility. The results showed that the use of Nelder-Mead with Real coded Genetic Algorithms has been very significant in improving the optimum shape of a solid C-frame cross-section subjected to a combined tension and bending stresses. The hybrid optimization method could be extended to more complex shape optimization problems.
Surface Registration and Integration in a Reverse Engineering System for Rapid Manufacturing
Authors: Li L. , Schemenauer N. , Peng X. , Zeng Y. , Gu P. 
Published: December 2020

Abstract
Three-dimensional data acquisition, surface registration and integration as well as subsequent rapid manufacturing are important processes in reverse engineering. This paper describes a reverse engineering system for rapid manufacturing of complex objects. The system consists of a three-dimensional digitizer (3D Optical Digitizing System), surface reconstruction software and a rapid prototyping machine. The surface reconstruction software has three major components: 1) range view registration by an iterative closed-form solution, which uses Binary Space Partitioning (BSP) tree to accelerate computation; 2) range surface integration by reconstructing an implicit function to update the volumetric grid; and 3) iso-surface extraction by a Marching Cubes algorithm. The surface reconstruction software exports models in STL format for rapid prototyping. A FDM 2000 machine is used to manufacture products. Examples are included to illustrate the systems and the methods.
“Intelligent” Optimal Design of Woven Composites
Authors: Zarka Joseph , Doux Thierry 
Published: December 2020

Abstract
By the coupling of the existing knowledge of experts, the numerical results and the experimental data with the help of some special automatic learning and optimization techniques, it is now possible to propose a very simple tool to design materials. The purpose of this paper is to show its particular application to the very difficult design of woven composites where it is necessary to adjust the mechanical properties, the electromagnetic properties and taking care of the price too.
Intelligent Optimal Design of a Beam During the Crash
Authors: Zarka Joseph , Navidi Pirouz 
Published: December 2020

Abstract
We consider the optimal design of a beam. To improve the safety of a car during the crash, it is needed to dissipate the maximum of energy within a limited displacement but with a limited acceleration at the level of the driver/passengers. The beam may have different complex cells linked with continuous or spot solders. In a special office, they have to design a beam. In Germany, in United Kingdom, and also inside all the automotive industries, dedicated centers to test such beams were created. Other centers have developped numerical simulations. Usually, for each family of beams, a Design of Experiments is performed.
It is necessary to find its optimal design. Until now, this was not possible, as the CRASH is a very complex problem and the tests or numerical simulations are too expensive to allow the succssive iterations.
Design Synthesis of Path Generating Compliant Mechanisms by Evolutionary Optimization of Topology and Shape
Authors: Tai Kang , Cui Guang Yu , Ray Tapabrata 
Published: December 2020

Abstract
This work demonstrates the successful synthesis of path generating compliant mechanisms by the process of topology and shape design optimization. As geometric topology variation of continuum structures is difficult to treat and analysis of the displacement path or trajectory of such structures is computationally intensive, a highly effective and efficient optimization methodology is needed. This paper describes the use of a recently developed morphological geometric representation scheme coupled with an evolutionary algorithm to synthesize the mechanism. The scheme uses arrangements of skeleton and ‘flesh’ to define structural geometry, which facilitates transmission of topological/shape characteristics across generations in the evolutionary process and will not render any geometrically invalid designs. The evolutionary algorithm solves the problem as a discrete optimization problem, with a proficient constraint handling capability.
Edge Detection in Reverse Engineering Using a Virtual CMM
Authors: Schreve K. , Basson A. H. 
Published: December 2020

Abstract
This paper describes a method to reconstruct edges, i.e. the intersection curves of adjacent non-tangent surfaces, from point clouds. The method is quick, easy to use and provides accurate results. It does not rely on extending surface patches that were individually fitted to the segments of the point data. Only edges of C1 discontinuity and C0 continuity are considered. The method samples the point cloud by simulating a co-ordinate measurement machine (CMM). The edge detection procedure is semi-automatic and only requires a few simple inputs from the user. The technique can also be implemented as a measurement strategy on a CMM.
Evaluating Manufacturing and Assembly Errors in Rotating Machinery to Enhance Component Performance
Authors: Tumer Irem Y. , Huff Edward M. 
Published: December 2020

Abstract
Manufacturing and assembly phases play a crucial role in providing products that meet the strict functional specifications associated with rotating machinery components. The errors resulting during the production of such components are correlated with the vibration and noise emanating from the final system during its operational lifetime. Vibration and noise are especially unacceptable elements in high-risk systems such as helicopters, resulting in premature component degradation and an unsafe flying environment. In such applications, individual components often are subject to 100% inspection following production, as well as during operation through rigorous maintenance, resulting in increased product development cycles and high production and operation costs. In this work, we focus on providing designers and manufacturing engineers with a technique to evaluate vibration modes and levels for each component or subsystem prior to putting them into operation. This paper presents a preliminary investigation of the correlation between manufacturing and assembly errors and vibrations, using an experimental test rig. A factorial design is used to study the effects of: 1) different manufacturing instances; 2) different assembly instances; and, 3) varying shaft speeds. The results indicate a correlation between manufacturing or assembly errors and vibrations measured from accelerometers. Challenges in developing a tool for design and manufacturing engineers are identified, followed by a discussion of future work.
Flexible Design Methodology
Authors: Roser Christoph , Kazmer David 
Published: December 2020

Abstract
A flexible design methodology is developed to minimize the effect of uncontrolled variation by modeling potential design and manufacturing corrections in the product development process. Using this flexibility methodology, the different defect modes and the likelihood of these defects occurring is evaluated. For every defect mode, all design change options are investigated including the cost and probability of selection. The expected cost of the initial design including design changes is determined, thus allowing development of improved, more flexible designs. The theoretical method is demonstrated using an example. The results indicate that small changes in design variables may reduce the likelihood and cost of future design changes, yet provide opportunity for downstream cost minimization.
Computing Exact Global Accessibility Cones for Polyhedral Objects
Authors: Dhaliwal Savinder , Gupta Satyandra K. , Huang Jim 
Published: December 2020

Abstract
This paper describes an algorithm for computing exact global accessibility cones for various faces (i.e., the set of directions from which various faces are accessible) of a polyhedral object. In contrast to previously published algorithms that compute approximate global accessibility cones for a face by sampling a set of discrete points from the face, the algorithm presented in this paper computes the exact global accessibility cones. In this paper, we describe exact mathematical conditions and the associated procedure for determining the set of directions from which a planar face with triangular boundary is inaccessible due to another face in the object. By utilizing the procedure to compute the exact inaccessibility region for a face, we present an algorithm for computing global accessibility cones for various faces in the object. These global accessibility cones are represented in a convenient matrix and can be used to support a wide variety of accessibility queries for the object.
Do-It-Right-First-Time (DRFT) Approach to Design Structure Matrix (DSM) Restructuring
Authors: Yassine Ali A. , Whitney Daniel E. , Lavine Jerry , Zambito Tony 
Published: December 2020

Abstract
This paper argues, using two real-world applications from the automotive industry, that the biggest benefit of a Design Structure Matrix (DSM) model may come not from resequencing and partitioning, but rather from “rewiring” the process/blocks. “Rewiring” means redefining relationships among elements and/or inserting new elements into the matrix. This requires intimate understanding of the process and cannot be done with application of context-free partitioning algorithms.
The Do-it-Right-First-Time (DRFT) approach to DSM restructuring is another way to look at a DSM by inspecting the sources of iteration within a block and reversing it through inserting a DRFT activity at the beginning of the block. In this way, the traditional Design-Build-Test “Cycle” is reversed into a DRFT-Design-Build “Sequence”. That is, the “wiring diagram” of a process or system overpowers the behavior of the individual nodes, so changing the system requires changing the wiring.
Using Indifference Points in Engineering Decisions
Authors: Scott Michael J. , Antonsson Erik K. 
Published: December 2020

Abstract
Multi-criteria decision support methods are common in engineering design. These methods typically rely on the specification of importance weights to accomplish trade-offs among competing objectives. Such methods can have difficulties, however: they may not be able to select all possible Pareto optima, and the direct specification of importance weights can be arbitrary and ad hoc. The inability to reach all Pareto optima is shown to be surmountable by the consideration of trade-off strategy as an additional parameter of a decision. The use of indifference points to select a best solution, as an alternative to direct specification of importance weights, is presented, and a simple truss design example is used to illustrate the concepts.
Closed Form Solutions for Connectivity and Connectivity of Motion in Mechanisms
Authors: Kohli D. , Razmara N. , Dhingra A. K. 
Published: December 2020

Abstract
This paper presents a closed form solution for determining connectivity between any two links in mechanism. The formulation is based on graph theory and its modification. The proposed approach could be applied to both planar and spatial mechanisms including combined planar-spatial mechanisms. Further, the mechanism may have multiple closed loops and/or open-chain substructures. A new concept of Connectivity of Motion has been introduced to determine the connectivity between any two links when the mechanism under consideration has special arrangement of adjacent joints such as joints with parallel and/or intersecting axes. Four examples are presented to illustrate connectivity calculations in spatial mechanisms.
Application of Instantaneous Invariants to the Synthesis of Linkages
Authors: Shyu Jenq-Huey 
Published: December 2020

Abstract
This paper presents the development of an efficient synthesis technique to synthesize planar triads and six-link mechanisms satisfying the prescribed instantaneous motions, by using the method of instantaneous invariants. The application of planar path curvature theory is extended to the synthesis of planar triads. A complete classification of planar triads is presented. Different synthesis applications of planar six-link mechanisms are discussed, and their design procedures are stated in detail.
Kinematic Synthesis of Binary Actuated Mechanisms for Rigid Body Guidance
Authors: Hanchak Michael S. , Murray Andrew P. 
Published: December 2020

Abstract
This paper presents a method for designing mechanisms composed of Revolute-Binary state prismatic-Revolute (RBR) chains for rigid body guidance. Where a prismatic joint allows for any distance between two revolute joints, a binary state prismatic joint reaches two distances precisely. A single RBR chain can be designed to reach six positions. A parallel arrangement of three RBR chains can be assembled at the six positions but, in general, is not a viable kinematic solution. By requiring the arrangement of three RBR chains to share specific fixed and moving pivots, called an N-type arrangement, four positions are reachable. Further, the design space is quickly searchable for singularity-free solutions. Examples illustrate a solution to a four position synthesis problem and a ten position problem using a serial assembly of these mechanisms.
Dynamics of a Piezoelectrically Actuated Vibratory Feeder
Authors: Chang Shuo Hung , Yang T. W. 
Published: December 2020

Abstract
This paper presents the development of a vibratory parts feeder driven by piezoelectric bimorph actuators. Mathematical models to describe dynamic behaviors of the piezoelectric bimorph actuator, vibratory parts feeder, and kinematics of the moving parts are formulated and numerically solved. Design factors such as the vibration amplitude, vibration frequency and vibration angle that affect the performance of the parts feeder is quantitatively investigated. Operating at the resonant vibration, the developed vibratory parts feeder achieves a high operating frequency and fine feed steps.
The Optimum Quality Index for a Spatial Redundant 8-8 In-Parallel Manipulator
Authors: Zhang Yu , Duffy Joseph , Crane Carl D. 
Published: December 2020

Abstract
The quality index for a redundant 4-4 in-parallel manipulator with a square platform and a square base was obtained in [1]. Following this, the quality index for a redundant 4-8 manipulator with a square platform and an octagonal base was determined in [2]. In this paper the optimal quality index for a redundant 8-8 manipulator is determined. The device has an octagonal platform and a similar octagonal base connected by eight legs. The quality index is defined as a dimensionless ratio which takes a maximum value of 1 at a central symmetrical configuration that is shown to correspond to the maximum value of the square root of the determinant of the product of the manipulator Jacobian by its transpose. The Jacobian matrix is none other than the normalized coordinates of the eight leg lines. It is shown that the quality index can be used as a constructive measure of not only acceptable and optimum design proportions but also an acceptable operating workspace (in the static stability sense). The analysis of the redundant 8-8 manipulator described here can be used to model and design a self-deployable space structure that has a pair of flexible octagonal antenna platforms in the base and top platform.
Classification of 6-SPS Parallel Manipulators According to Their Components
Authors: Kong Xianwen , Gosselin Clément M. 
Published: December 2020

Abstract
The complexity of the forward displacement analysis (FDA) of 6-SPS parallel manipulators1 varies to a great extent with the change of their geometric parameters. This paper presents a classification of the 6-SPS parallel manipulators according to their components. At first, we give the components for the 6-SPS parallel manipulator. A component refers to a part of the 6-SPS kinematic chain in which the number of actuators is equivalent to the degree of freedom. In addition to the commonly used rigid bodies, points and (straight) lines are also taken as elements of the components. Type synthesis of the 6-SPS parallel manipulators is then performed. The influence of the types of components on the maximal numbers of configurations and the degrees of the characteristic polynomials of the 6-SPS parallel manipulators is then revealed. The number of redundant sensors needed to reduce the FDA of 6-SPS parallel manipulators to the solution of several univariate quadratic equations in sequence based on the component method is also presented.
Spherically-Actuated Platform Manipulator
Authors: Williams Robert L. , Poling Dana B. 
Published: December 2020

Abstract
This paper presents the inverse and forward pose kinematics solutions for a novel 6-dof platform manipulator, actuated by two base-mounted spherical actuators. The moving platform is connected to the fixed base by two identical SPU (alternatively, SRU) serial chain legs. The S-joint is active, and remaining two joints in each chain are passive. The numerical Newton-Raphson technique is employed to solve the pose problems. Unfortunately, the passive joint variables cannot be ignored in the pose kinematics solutions as they can for the Gough/Stewart platform. Examples are presented and hardware has been built, using two Rosheim Omni-Wrists on loan from NASA.
Least Squares Tracking on the Euclidean Group
Authors: Han Youngmo , Park F. C. 
Published: December 2020

Abstract
A large class of problems in robotics, e.g., tracking with obstacle avoidance, compliant motion control, and complex assembly, can be formulated as a least-squares tracking problem on the Euclidean group subject to constraints on the state and/or control. In this paper we develop a general, mathematically rigorous optimal control framework for this class of problems, and derive a simple closed-form analytic solution. Our formalism can be viewed as generalization to the Euclidean group of the linear quadratic regulator (LQR) subject to state equality constraints. Examples from force-guided complex assembly and tracking with obstacle avoidance are given.
Contact Analysis of Helical Face Gears
Authors: Jacquin Colin-Yann , Guingand Michèle , de Vaujany Jean-Pierre , Play Daniel 
Published: December 2020

Abstract
This paper presents an analytical method developed to design and study the tooth geometry and contact characteristics of helical face gears.
The tooth geometry is first defined while simulating the meshing of the face gear with the shaper used to cut it. A second meshing simulation is then performed between the face gear and the meshing pinion to determine some characteristics of kinematics, i.e. exact location of contact points, theoretical contact ratio, kinematics transmission error.
The computation method is very general and allows to study several types of face gears : crossed axes or offset, varying shaft angle, spur or helical pinion. Cutting and assembling errors are also included in the simulations.
The study has shown the influence of the different errors on the kinematics characteristics. Relative sensibility of helical face gears under various misalignments has been also established.