bluuebunny/crossref_metadata_2025_split huggingface dataset:
Concurrent Product Design Based on Simultaneous Processing of Design and Manufacturing Information by Utility Analysis
Authors: Yoshimura Masataka , Kondo Hideyuki 
Published: March 2021

Abstract
A methodology for concurrent decision making of factors concerning product design and product manufacturing is proposed for obtaining better product designs from a wider global viewpoint of the product performance and the product manufacturing cost according to the concept of concurrent engineering. In this method, first, a function expressing the satisfactory level of the manufacturing division and a function expressing the satisfactory level of the design division are formulated for the product design being regarded. Then, an integrated higher ranking decision making utility function is formulated using these two satisfactory level functions by the utility analysis. Next, Pareto optimum solution sets of the two multiobjective optimization problems of maximization of the product performance and minimization of the product manufacturing cost are obtained for alternative product designs. Finally, on the Pareto optimum solution curves, the values of the integrated satisfactory levels are obtained and the most preferable design solution is selected. An applied example of this concurrent design procedure is given to demonstrate it’s effectiveness in comparison to a conventional design procedure.
Genetic Algorithm-Based Design of Energy Absorbing Laminated Composite Beams
Authors: Averill R. C. , Punch W. F. , Goodman E. D. , Lin S.-C. , Yip Y. C. , Ding Y. 
Published: March 2021

Abstract
This paper describes a general approach to structural design using Genetic Algorithms, and an application of that approach to the design of energy absorbing laminated composite beams containing distributed thin, compliant layers. We first discuss a method for applying a Genetic Algorithm (GA) to structural design, using it as an evolutionary search optimizer in conjunction with a structural simulator as its objective function. The simulator used is an efficient and robust special purpose finite element model based on a layerwise laminate theory. The GA “designs” the beam by selecting material assignments for the subregions and the locations of compliant layers, and evaluates the design using the simulator. The efficiency of the GA search is improved by use of the “injection island” architecture. The results demonstrate that the parallel GA architectures achieved algorithmic superlinear speedup to similar quality of solution in comparison with single-population genetic algorithms.
A Two Level Parallel Evolution Strategy for Solving Mixed-Discrete Structural Optimization Problems
Authors: Thierauf Georg , Cai Jianbo 
Published: March 2021

Abstract
A method for the solution of mixed-discrete structural optimization problems based on a two level parallel evolution strategy is presented. On the first level, the optimization problem is divided into two subproblems with discrete and continuous design variables, respectively. The two subproblems are solved simultaneously on a parallel computing architecture. On the second level, each subproblem is further parallelized by means of a parallel sub-evolution-strategy. Periodically, the design variables in the two groups axe exchanged. Examples are included to demonstrate the implementation of this method on a 8 nodes parallel computer.
A Fuzzy Sequential Linear Programming Algorithm for Engineering Design Optimization
Authors: Hsu Yeh-Liang , Lin Yu-Fa , Guo Yu-Shuei 
Published: March 2021

Abstract
An optimization process can be viewed as a closed-loop control system. Traditional “controllers”, the numerical optimization algorithms, are usually “crisply” designed for well defined mathematical models. However, when applied to engineering design optimization problems in which function evaluations can be expensive and imprecise, very often the crisp algorithms will become impractical or will not converge. A common strategy for designers is to monitor the optimization process and keep “tuning” the process in an interactive manner, using their judgment on the information obtained from previous iterations, and their knowledge of the problem. This paper presents how the heuristics of this human supervision can be modeled into the optimization algorithms using fuzzy set theory. A fuzzy version of sequential linear programming is used to demonstrate this idea. Fuzzy rules, which describe the human supervision during the optimization process, are combined with the numerical rules of the original algorithm to refine the output of each iteration. Several design optimization problems are used to show the feasibility and practicality of this approach.
A Study on Optimum Design Using Fuzzy Numbers As Design Variables
Authors: Arakawa Masao , Yamakawa Hiroshi 
Published: March 2021

Abstract
In this study, we summerize the method of fuzzy optimization using fuzzy numbers as design variables. In order to detect flaw in fuzzy calculation, we use LR-fuzzy numbers, which is known as its simplicity in calculation. We also use simple fuzzy numbers’ operations, which was proposed in the previous papers. The proposed method has unique characteristics that we can obtain fuzzy sets in design variables (results of the design) directly from single numerical optimizing process. Which takes a large number of numerical optimizing processes when we try to obtain similar results in the conventional methods. In the numerical examples, we compare the proposed method with several other methods taking imprecision in design parameters into account, and demonstrate the effectiveness of the proposed method.
Domains of Interference Between Working Bodies in Mechanisms and Manipulators
Authors: Haug Edward J. , Adkins Frederick A. , Luh Chi-Mei , Wang Jia-Yi 
Published: March 2021

Abstract
Criteria for the set of all points in a pair of working bodies in a mechanism or manipulator that can coincide for any kinematically admissible configuration of the underlying mechanism, called the domain of interference between the bodies, are formulated. Kinematic equations for the mechanism and parameterizations of the domains of the working bodies are used to derive analytical criteria for domains of interference. Three complementary problems are formulated and analyzed to characterize (1) the set of points in one of the interfering bodies that are occupied by any point in the second body, (2) the set of points in one of the interfering bodies that are occupied by any point on the boundary of the second body, and (3) the set of all points in space that are simultaneously occupied by points in the interfering bodies; each condition occurring for any kinematically admissible configuration of the mechanism. Analytical criteria for the boundaries of domains of interference for each of the three problems arc derived, based on row-rank deficiency of a sub-Jacobian matrix associated with the kinematic equations for each of the problems. Numerical methods for mapping boundaries of domains of interference are presented and illustrated for planar Stewart platforms with domes attached that are characteristic of flight or ground vehicle simulators.
Mechanical Design of a Non-Overconstrained Walking Machine
Authors: Fichter E. , Fichter B. 
Published: March 2021

Abstract
This paper describes the mechanical design of a walking machine that avoids overconstraint. All current walking machines that are also capable of standing on their own are overconstrained and must depend on force control algorithms to control joints. From observations of darkling beetles we have concluded that it is possible for them to perambulate while keeping their bodies constrained but not overconstrained. Our walking machine was built to test hypotheses of how these beetles walk. We discuss the aspects of beetle leg kinematics that are most important for non-overconstrained walking.
Numerical Kinematic Analysis of the Motor-Vehicle Multi-Link Suspension System
Authors: Mohamed Maher G. , Attia Hazem A. 
Published: March 2021

Abstract
In this paper, an efficient numerical algorithm for the kinematic analysis of a multi-link suspension system is presented. The suspension system is usually used for rear driven axles of current car productions. The kinematic analysis of the one-DOF spatial multi-link suspension mechanism which is composed of binary links connected by spherical joints is carried out in terms of the rectangular Cartesian coordinates of some defined points in the links and at the joints. By properly locating the points at the centers of the spherical joints, all the kinematic constraints are automatically eliminated. Geometric nonlinear constraints are introduced to fix the relative positions of the points on the rigid bodies. An additional drivingconstraint is added as a function of the input driving angular position. The nonlinear constraint equations are solved by iterative numerical methods. The corresponding velocity and acceleration equations are derived by differentiating the constraint equations. These equations are linear and can easily be solved numerically to yield the velocities and accelerations of the unknown points on the wheel knuckle. The velocities and accelerations of other points of interest can be calculated if their positions are specified. Also the angular velocities and accelerations of any link in the mechanism are evaluated from the Cartesian coordinates, velocities, and accelerations of any three defined points on the link. The presented formulation in terms of this system of coordinates is simple and involves only elementary mathematics. A numerical example is presented.
On the Classification of Automatic Tool Changers for Machining Centers
Authors: Yan Hong-Sen , Yiou Chih-Wen , Chen Fu-Chen , Chang Paul 
Published: March 2021

Abstract
This paper presents a seven-code system for the classification of automatic tool changers for machining centers according to their complexity. The first code is the types of tool magazines. The second code is the relative positions of the tool magazine and the spindle. The third code is the types of tool change mechanisms. The fourth code is the types of motion for grasping tools. The fifth code is the types of insertion and extraction of tools. The sixth code is the types of motion of changing tools. The last code is the positions of the spindle. Several examples are given to demonstrate the applications.
An Historical View of Mechanical Failure Prevention
Authors: Pusey Henry C. 
Published: March 2021

Abstract
This paper provides a general overview of developments and progress in mechanical failure prevention technology, primarily over, the last three decades. The principal reference sources used are the proceedings of the 50 conferences of the Mechanical Failures Prevention Group (MFPG), now the Society for Machinery Failure Prevention Technology (MFPT). Since many technical disciplines are involved in this complex technology, an attempt is made to place mechanical failure prevention in perspective. Discussion of the evolving technology is presented under four topic areas that serve to cover most of the elements of this broad-based field. These topics are Diagnostics and Prognostics, Failure Analysis, Life Extension and Durability, and Sensors Technology. Selected subtopics and methodologies are also discussed. The importance of the relationship and interaction of the numerous technical disciplines involved in mechanical failure prevention technology is stressed. Significant advancements in the technology are emphasized. Some technological gaps and problems that are yet to be solved are identified.
Damage Tolerance Assessment of a Paper Pulp Refiner Disk
Authors: Cartwright D. J. , Orbison J. G. , Kohler G. , Shah H. 
Published: March 2021

Abstract
As long as materials continue to have imperfections in their structure, failure by cracking will continue to be a consideration in design. Cracks may be the result of material in homogeneity, service loading and may also be introduced during the manufacturing of either, the material itself or the structure in which the material is used. In the presence of a crack, a structure is more prone to fail at stress levels lower than those based on standard yield criteria. Components such as rotating machinery store large amounts of energy during operation and a fracture resulting from cracks in the rotating parts can be especially dangerous. Thus it is necessary to consider the failure mode of fracture when designing the disk and this requires a knowledge of the stress intensity factor of the crack in the disk and the fracture toughness of the disk material. In the present work the Boundary Element Method combined with Subtraction of Bueckner Singular Fields is used to obtain weight functions for an internal radial crack in an annular disk. A previously developed, general representation, of the weight function leads to integrals that can be evaluated analytically to obtain the stress intensity factor. Stress intensity factors are determined for the disk, containing a radial crack in a typical pulp refiner and the minimum level of fracture.
Aggregation Functions for Engineering Design Trade-Offs
Authors: Scott Michael J. , Antonsson Erik K. 
Published: March 2021

Abstract
The Method of Imprecision (MoI) is a formal theory for the manipulation of preliminary design information that represents preferences among design alternatives with the mathematics of fuzzy sets. Using the MoI, different design tradeoff strategies can be applied. To date, two aggregation functions have been developed for the MoI, one representing a compensating strategy and one a non-compensating strategy. Other research on aggregation functions on fuzzy sets has focused on two classes of functions that are not suitable for engineering design. The general restrictions on design-appropriate aggregation functions are discussed, and a family of functions ranging from the non-compensating min to the compensating product of powers is presented. An application to preliminary engineering design is given.
Theoretical and Numerical Validation of the Stochastic Interrogation Experimental Method
Authors: Kimble Bart W. , Cusumano Joseph P. 
Published: March 2021

Abstract
Stochastic interrogation is an experimental method that uses transient trajectories starting at numerous pseudo-random initial conditions to obtain detailed information about the flow of a dynamical system in phase space. From this flow information, various global dynamical phenomena can be studied, such as the transition to complex basin boundaries, chaotic transients, and strange non-attracting sets. The existence of these features in turn allows the occurrence of a homoclinic bifurcation to be inferred, even when all attractors in a system are nonchaotic. In this paper, the validity of inferences made using the stochastic interrogation experimental method is checked with the aid of a numerical model, using theoretical predictions from Melnikov theory and direct computations of invariant manifolds.
Dynamic Response and Stability of Pressurized Gas Squeeze-Film Dampers
Authors: Arakere Nagaraj K. , Ravichandar B. C. 
Published: March 2021

Abstract
Compressible squeeze films, an important and interesting area in gas lubrication, have been relatively neglected in recent times. Aircraft engines are being designed with light weight flexible rotors operating at high speeds and temperatures that may eventually eliminate the use of oil lubrication. A gas or air SFD might be a viable alternative to a conventional oil damper, in high temperature applications that preclude the use of oil lubrication. Oil squeeze-film dampers currently being used for rotordynamic control will not be viable at temperatures above 350 °F, due to limitations on lubricant oil temperature. Gas SFD’s are well suited for use in high temperature gas lubricated foil bearings. This paper presents an analysis of pressurized air dampers, similar to a hydrostatic gas bearing. Pressurized air is supplied through a series of orifices in the bearing midplane. Air flows through the orifices and the resulting pressure forces are calculated using a simple gas-flow model, as in orifice compensated hydrostatic bearings.
A small perturbation analysis of the shaft center yields the stiffness and damping coefficients, for centered circular motions. Damping characteristics are studied for a range of parameters such as supply pressure, orifice diameter, pocket volume, orbit size, number of orifices and shaft speed. Results show that maximum damping forces are generated for near choking flow conditions. The damping force becomes negligible at frequencies above 350 Hz. For damping force to be present, the gas pressurization has to exert a force on the rotor opposing the instantaneous velocity, or, 90 degrees out of phase with displacement Linear stability of unbalanced dampers undergoing centered circular orbits, is also investigated, in view of their relevance to rotordynamics. Damper design curves are presented for various parameters.
Stability of Time Varying Systems
Authors: Colonius Fritz , Kliemann Wolfgang 
Published: March 2021

Abstract
The stability behavior of time varying systems can be studied using the concept of Lyapunov exponents and their corresponding Lyapunov subspaces. For linear time varying systems the entire Lyapunov spectrum can be approximated by the Floquet exponents of periodic systems. This leads to a variety of stability results, including the characterization of stability radii. Furthermore, a structural stability type theorem shows that stability features of time varying hyperbolic systems persist under small perturbations. For nonlinear time varying systems a stable manifold theorem allows us to interpret the linear results for the nonlinear system locally around an equilibrium point.
Vibration Suppression of a Flexible Beam Using Center Manifold Theory
Authors: Khajepour Amir , Golnaraghi Farid , Morris K. A. 
Published: March 2021

Abstract
In this paper we develop a nonlinear control strategy based on modal coupling using the center manifold theory. As an example we use the technique for vibration suppression of a flexible beam. The controller in this case is a mass-spring-dashpot mechanism which is free to slide along the beam. The equations of the plant/controller are coupled and nonlinear, and the linearized equations of the system have two uncontrollable modes. As a result, the performance of the system can not be improved by linear control theory or by most conventional nonlinear control techniques.
We use the normal forms method to simplify the center manifold equations and derive a relation which includes all system parameters. We then show that there exists a set of optimal controller parameters (feedback gains, controller damping and frequency) which maximized the energy dissipation. Finally we consider the stability and design issues, and use numerical simulation to verify the results.
On the Non-Linear Dynamics of a Traveling Cable With Small Sag
Authors: Reuter Christoph G. , Hagedorn Peter 
Published: March 2021

Abstract
Traveling cables or threadlines appear in a number of technical applications such as textile machinery, V-belts, ski lifts, funiculars and also in simple models of traveling webs in paper machinery. The mechanical models used so far, most often neglect the effect of sag due to the weight of the cable, although it is well known that in some cases it may be quite important. In this paper, the authors develop a particularly simple model for translating cables using the assumption that the longitudinal inertia forces are negligible in comparison to the transversal inertia forces if the sag of the cable is sufficiently small. This assumption has already been made in a study of linear vibrations of stationary cables in 1970 by Irvine & Caughey. This lead to surprising results which have also been verified experimentally in the laboratory.
The extended model presented in this paper includes gyroscopic and nonlinear terms in the equations of motion, related to the cable transport velocity and geometric nonlinearities. As a particular case (zero longitudinal speed and linear theory) the model of Irvine & Caughey is again contained in the present analysis. The linear and non-linear vibrations about a steady state solution are studied. The results show some interesting features which may also be relevant to technical systems if the transport speed is sufficiently high.
Spectral Analyses of Nonlinear Interactions
Authors: Balachandran Balakumar , Khan Khalil A. 
Published: March 2021

Abstract
Signals pertaining to motions of nonlinearly coupled oscillators are studied using higher-order spectral analyses. The analyses is used to understand the role of phase coupling in nonlinear interactions between two or more Fourier components. For certain motions of weakly nonlinear systems, analytical approximations are obtained for relevant higher-order spectra and coherence functions. Numerical studies are conducted to verify analytical predictions and to illustrate the usefulness of spectral analyses for different cases.
Dynamics of Geometrically Exact Sandwich Beams/1-D Plates: Computational Aspects
Authors: Vu-Quoc L. , Deng H. 
Published: March 2021

Abstract
A Galerkin projection of the equation of motion of geometrically-exact sandwich beams, applicable to 1-D plates, formulated in Vu-Quoc & Ebcioğlu [1995] is presented here. The beam could take any arbitrary initial position in the 2-D space. Each layer of the beam could have different material constants with no restriction on the mass distribution and layer thickness; further, each layer could take on different length, thus allows the modeling of multilayer structures with ply drop-off. Finite rotations and shear deformation are accommodated for in each layer. The deformed cross section of the beam is continuous, piecewise linear. The continuity of displacement across the interlayer boundaries is exactly enforced. Extensive numerical examples including sandwich structures with ply drop-off, free flying and spin up maneuver of sandwich beams are presented to illustrate the applicability and versatility of the proposed formulation.
Analysis of a Nonlinear Friction Damping Mechanism in a Fluid-Structure Interaction System
Authors: Gottlieb Oded , Feldman Michael , Yim Solomon C. S. 
Published: March 2021

Abstract
Analysis of a nonlinear friction damping mechanism in a fluid-structure interaction system is performed by combining a generalized averaging procedure with a recently developed identification algorithm based on the Hilbert transform. The system considered includes a nonlinear restoring force and a nonlinear dissipation force incorporating both viscous and structural damping. Frequency and damping response backbone curves obtained from simulated data are compared with analytical and approximate solutions and are found to be accurate. An example large scale experiment exhibiting viscous and Coulomb damping is also analyzed resulting in identification of system parameters.
Experimental Investigation of Friction Dynamics Associated With Normal Load
Authors: Dupont Pierre E. , Kasturi Prakash S. 
Published: March 2021

Abstract
In the last five years, it has become clear that for a broad range of systems which exhibit significant friction, the dynamics of the friction itself must be included to reach a complete understanding of system stability and control issues. Dynamics associated with variations in velocity have received most of the attention while those associated with variations in normal load have been largely ignored. This paper presents results of ongoing research in the experimental identification of friction dynamics due to variations in both normal load and velocity for a line contact in boundary lubrication. Tests were conducted with inputs consisting of step changes in velocity and normal force. Our analyses indicate that a first or second order model is necessary to represent dynamic friction behavior associated with these inputs.