bluuebunny/crossref_metadata_2025_split huggingface dataset:
Reduction of Acquisition Time Through New Design for Assembly Heuristics
Authors: Sturges Robert H. , Hunt David O. 
Published: March 2021

Abstract
Rearranging component positions and orientations inside products can reduce the acquisition times associated with handling distance and component orientation. Modeling the acquisition process with an information-based Design for Assembly methodology identifies and quantifies acquisition difficulty for manual and automatic processes. Heuristics based on evaluations of acquisition difficulty guide the relocation and reorientation of components inside the product to reduce assembly time. Since acquisition time averages one third of the total assembly time, significant improvements are shown to be feasible. A new information flow from downstream assembly issues into product design is demonstrated.
A Network Reliability Approach to Optimal Decomposition of Design Problems
Authors: Michelena Nestor F. , Papalambros Panos Y. 
Published: March 2021

Abstract
This article addresses the problem of identifying the optimal decomposition of a design problem. Methods for solving decomposed mathematical programming problems require that an appropriate structure suitable for decomposition be identified. This first step consists of identifying linking (or coordinating) variables or functions that effect independent subproblems coordinated by a master problem. We present a network reliability-based solution of the optimal decomposition problem that avoids heuristics and subjective criteria for the identification of linking variables and evaluation of partitions. The relationships among design variables, i.e., the constraint functions, are modeled as the processing units of a network. The design variables themselves are modeled as the communication links between these units. The optimal decomposition problem is then reduced to one of finding the links that have the most effect on the overall network connectivity. Two measures of network reliability, all-terminal and pair-connected reliability, are used as measures of network (and design problem) connectivity. The optimal decomposition is attained by minimizing the network reliability while maximizing the number of operating links.
Structural Optimization Using a Generalized Convex Approximation
Authors: Chickermane Hemant , Gea Hae Chang 
Published: March 2021

Abstract
To reduce the computational cost of structural optimization problems, a common procedure is to generate a sequence of convex, approximate subproblems and solve them in an iterative fashion. In this paper, a new local function approximation algorithm is proposed to formulate the subproblems. This new algorithm, called Generalized Convex Approximation (GCA), uses the sensitivity information of the current and previous design points to generate a sequence of convex, separable subproblems. This algorithm gives very good local approximations and leads to faster convergence for structural optimization problems. Several numerical results of structural optimization problems are presented.
Topology Optimization: A New Micro-Structure Based Design Domain Method
Authors: Gea Hae Chang 
Published: March 2021

Abstract
Topology optimization is the most complicated problem in structural optimization. One common approach is to utilize the concept of the design domain, such as the homogenization method and the density function approach. In this paper, a new micro-structure based design domain method is proposed. This new method gives simple closed-form expressions for effective Young’s modulus and effective shear modulus in terms of phase properties and volume fractions. Using these simple relations, topology optimization problems can be formulated and solved using mathematical programming algorithms. Results of some design examples obtained from the new method are presented.
Aspects on Process Planning Issues in Axiomatic Design
Authors: Vallhagen Johan 
Published: March 2021

Abstract
This paper addresses some limitations of the axiomatic design theory (AD) when designing complex products and matching manufacturing systems. The conclusion is that, for complex manufacturing systems, this cannot be done in such a straightforward way as described in literature. The original method is best used for manufacturing of parts only, i.e. to find the appropriate process variables (PVs).
In the case of complex manufacturing systems, a one-to-one mapping between physical domain and process domain is not possible since not all design parameters (DP) are components. Therefore, an additional process requirement domain (PR), proposed earlier, has been used. With it, the components are extracted from the DP hierarchy and mapped to different spaces in the manufacturing world. In these spaces, PRs and PVs are selected when designing the manufacturing system. An example is given to show the deficiencies and how to use the suggested modifications.
The Measurement Subspaces of Parallel Manipulators Under Sensor Redundancy
Authors: Baron Luc , Angeles Jorge 
Published: March 2021

Abstract
Using the concept of measurement subspaces of the leg-end-point position of general parallel manipulators, a linear kinematic model is derived. For a class of 6-dof leg-kinematic architectures of general geometry, the sets of sensed joints that lead to a measurement subspace are classified into 16 different types. For each of these types, a geometric interpretation and the equations for the computation of the measurement subspace from the readouts of a set of sensed joints, are provided. The design rules on the sensing of parallel manipulators in order to obtain the linear kinematic model are also derived.
Automobile Hood/Fender Design Optimization for Improved Pedestrian Head Impact Protection
Authors: Lemmon David R. , Huston Ronald L. 
Published: March 2021

Abstract
This paper presents procedures for automobile structure design to reduce head injury of pedestrians struck by the vehicle. The fender and hood seam of a 1988 Ford Taurus are modified to absorb the energy of a head impact. Two shape related design parameters are optimized for minimum Head Injury Criterion using finite element simulations. A design is presented which reduces Head Injury Criterion by over 50 percent. All analyses are conducted using the explicit, nonlinear, dynamic finite element code DYNA3D on a Cray YMP/832 supercomputer.
Type Synthesis of Compliant Mechanisms Employing a Simplified Approach to Segment Type
Authors: Murphy Morgan D. , Midha Ashok , Howell Larry L. 
Published: March 2021

Abstract
The formulation of design procedures for rigid-body mechanisms has benefited from the application of type-synthesis techniques. Therefore, with modifications to allow for inclusions of compliance, type synthesis is seen as a useful tool in the design of compliant mechanisms. Previous efforts have developed methods that result in a large number of possible design solutions to a given problem. This paper deals primarily with the development of a simplified compliant-mechanism type-synthesis methodology that limits the number of design solutions considered. The techniques are derived by modifying existing compliant mechanism type-synthesis techniques to yield a simpler model with greater pragmatic value.
Design of the Spatial 4C Mechanism for Rigid Body Guidance
Authors: Larochelle Pierre , McCarthy J. Michael 
Published: March 2021

Abstract
In this paper we present an algebraic formulation for the constraint manifold of the spatial CC dyad in the image space of spatial displacements. We then present a technique, utilizing the constraint manifold, for performing the dimensional synthesis of mechanisms for rigid body guidance through n positions. Finally, we present numerical results for 10 prescribed positions for the coupler of a spatial 4C mechanism.
Analysis and Synthesis of Linear Transmission Mechanisms: Coupled Mechanisms and Mechanisms Wth Prismatic Joints
Authors: Chang Sun-Lai 
Published: March 2021

Abstract
The characteristics of linear transmission mechanisms are studied. Using the characteristics, the kinematic and synthesis of linear transmission mechanisms are expanded. First, the synthesis of mechanisms with prismatic joints in the equivalent open-loop chain is developed. Then the kinematics and synthesis of mechanisms with coupled joint motion are also derived. Two coupled mechanisms are used as examples to demonstrate the application potential in the industry.
General Order Criteria for the Precision Position Synthesis of Single Degree-of-Freedom Planar Linkages
Authors: Mirth John A. 
Published: March 2021

Abstract
The order in which a single degree-of-freedom planar linkage passes through a series of design positions depends on both the relative orientations of a designated input link and the branch characteristics of that same link. The input link must have a continuous rotation as it passes through all design positions that lie on the same branch. The continuous rotation criteria does not apply to design positions on different branches of the linkage. Complete order conditions are presented for linkages with four design positions that lie on one to four separate branches.
“MKCIRCLES”: An Interactive Computer Graphics Design Tool to Solve the Generalized Three-Precision-Position Synthesis Problem
Authors: Cheng Pi-Ming , Rizq Raed N. , Erdman Arthur G. 
Published: March 2021

Abstract
A new interactive computer graphics program (MKCIRCLES) has been developed to solve the following three-precision-position dyad synthesis tasks: (i) motion generation, (ii) path generation with prescribed timing and (iii) a new solution strategy for (a) motion generation for a user-specified range of the prescribed-timing angular displacements, and (b) path generation with prescribed timing for a user-specified range of the rotations of the floating link. The latter two cases address a problem that is encountered in linkage design; namely, the need to specify limits that certain variables may range through as opposed to specifying fixed values that constrain the design unnecessarily, thus increasing the total number of designs from which to choose. As a result of this new approach, two planar regions, representing all permissible dyad ground-pivot locations and all permissible dyad moving-pivot locations, are identified and plotted. The program uses the properties of the circle-point circles (K1-circles) and the center-point circles (M-circles) throughout the synthesis procedure. MKCIRCLES also allows the designer to define a region in which the ground-pivots are constrained to lie and determine the corresponding moving-pivot region (and vice versa). The program is shown to be a useful design tool and provides greater geometric and kinematic insight into the general three-precision-position synthesis problem.
A Direct Rotatability Criterion for Spherical Four-Bar Linkages
Authors: Ma R. , Gupta K. C. 
Published: March 2021

Abstract
The necessary and sufficient conditions for the full input rotatability in a spherical four bar linkage are proved. The direct criterion is: for all twist angles α in the range [0, π], the excess (deficit) of the sum of the frame and input twist angles over (from) π should, in absolute value, be greater than that for the coupler and follower twist angles; the difference between the follower and input twist angles, in absolute value, should be greater than that for the coupler and follower twist angles. Application of the direct criterion to full rotatability of other links are discussed and some variations in the form of the criterion are developed.
Performance Quality, Sensitivity, and Tolerance Specification of Mechanisms
Authors: Ting Kwun-Lon , Long Yufeng 
Published: March 2021

Abstract
By employing Taguchi’s concept to mechanism synthesis, this paper presents the theory and technique to identify a robust design, which is the least sensitive to the tolerances, for mechanisms and to determine the tolerance specification for the best performance and manufacturability. The method is demonstrated in finite and infinitesimal position synthesis. The sensitivity Jacobian is first introduced to relate the performance tolerances and the dimensional tolerances. The Rayleigh quotient of the sensitivity Jacobian, which is equivalent to Taguchi’s signal to noise ratio, is then used to define the performance quality and a sensitivity index is introduced to measure the sensitivity of the performance quality to the dimensional tolerances for the whole system. The ideal tolerance specification is obtained in closed form. It shows how the tolerance specification affects the performance quality and that the performance quality can be significantly improved by tightening a key tolerance while loosening the others. The theory is general and the technique is readily adaptable to almost any form and type of mechanical system, including multiple-loop linkages and mechanical assemblies or even structures.
Long-Dwell, Finite-Dwell Linkages
Authors: Alam Askari Badre , Strait D. A. 
Published: March 2021

Abstract
A new class of long-dwell, finite-dwell linkages has been discovered. This paper presents the design methodology for the new type of mechanisms using a dual stiffness element (buckling column). Fabrication of a first new long dwell mechanism working prototype has been completed. The experimental system is described and results of numerical and experimental models are compared. Simplification of these new mechanisms via introduction of flexible links and joints is discussed.
Effects of Payload on the Vibrational Excitation of Robot Manipulators During Motion
Authors: Tu Q. , Rastegar J. 
Published: March 2021

Abstract
The effects of payload mass, size, and end-effector holding location on the vibrational excitation of manipulators during motion are determined based on a new method, referred to as the trajectory pattern method. This is accomplished by examining the harmonic content of the actuating torques (forces) required for open-loop tracking of a selected trajectory pattern, the relative amplitude of each harmonic, and the energy input to the system by each harmonic. The simplest possible trajectory pattern for point to point motions with zero end point acceleration and jerk is employed as the basis for this study. It is shown that the amplitude of each harmonic is affected differently by the addition of the payload. The amplitudes change depending on the direction of motion and the location of the path of motion within the workspace of the manipulator. The harmonic content of the required actuating torques are not affected. The study provides information for planning paths of motion and synthesizing trajectories that are from the vibration point of view less sensitive to the payload. As an example, the effects of payload on a plane 2R manipulator are studied.
Computerized Design of Low-Noise Face-Milled Spiral Bevel Gears
Authors: Litvin F. L. , Zhang Yi , Handschuh R. F. 
Published: March 2021

Abstract
An advanced design methodology is proposed for the face-milled spiral bevel gears with modified tooth surface geometry that provides a reduced level of noise and has a stabilized bearing contact. The approach is based on the local synthesis of the gear drive that provides the “best” machine-tool settings. The theoretical aspects of the local synthesis approach are based on the application of a predesigned parabolic function for absorption of undesirable transmission errors caused by misalignment and the direct relations between principal curvatures and directions for mating surfaces. The meshing and contact of the gear drive is synthesized and analyzed by a computer program. The generation of gears with the proposed geometry design can be accomplished by application of existing equipment. A numerical example that illustrates the proposed theory is presented.
Analysis and Synthesis of the Dual Roller-Cam Mechanism
Authors: Chang Sun-Lai 
Published: March 2021

Abstract
A mechanism with two roller-cam pairs as its moving joints has been introduced. In such a mechanism, higher efficiency and longer operating life cycles are expected because of the absence of slippage in its moving joints. The kinematic analysis of this class of mechanisms has been performed. An equivalent geared five-bar mechanism has been utilized for the analysis of velocity. Several characteristics pertaining to this class of mechanisms, such as action angle, force equilibrium and singular position, have been discussed. The synthesis of this class of mechanisms with circular cam profiles has also been studied.
A Kinematic Method for Improving Motion Characteristics of Cam-Follower Systems
Authors: Yan Hong-Sen , Tsai M. C. , Hsu M. H. , Fong M. K. , Hsieh W. H. 
Published: March 2021

Abstract
A cam is often assumed to be operated at a constant speed in designing a cam-follower system. And, to improve the motion characteristics is to do a new design by finding an appropriate cam-profile. From the kinematic point of view, this paper presents an alternative approach to improve the motion characteristics by varying the speed of the cam. Design criteria for selecting suitable cam speed trajectories are provided. Examples are given to illustrate the design procedure and also to show the feasibility.
Formulation of Multibody Dynamics Equations in Absolute or Relative Coordinates Using the Vector-Network Method
Authors: McPhee John J. 
Published: March 2021

Abstract
The objective of this paper is to show how a single linear graph representation of a multibody system can be used to derive the complete set of equations of motion in either absolute or relative coordinates, depending upon the elements selected into the spanning tree of the linear graph. Criteria for selecting a tree that gives the desired set of equations is given and the systematic nature of this graph-theoretical procedure, known as the Vector-Network Method, is demonstrated by means of two planar examples. The first is an open-loop compound pendulum, and the second is a closed-loop four-bar mechanism driven by a time-varying torque.
Recursive Dynamics of Overconstrained Mechanisms
Authors: Rein Udo 
Published: March 2021

Abstract
Overconstrained mechanisms contain loop-closure constraints which are redundant due to a special geometry of the links. Some reaction forces of an overconstrained mechanism cannot be calculated from the dynamics of the mechanism. This means that an overconstrained mechanism is statically indeterminate. The recursive formalism was originally developed to derive the equations of motion for open-loop kinematic chains, but it has been extended by various authors to closed-loop mechanisms. This paper discusses the recursive formalism when it is applied to an overconstrained closed-loop mechanism. It will be shown that the redundant loop-closure constraints lead to rather small singular, but consistent sets of linear equations for the reaction forces at the corresponding cut joints. This means that the reaction forces at those cut joints are not unique for an overconstrained mechanism, but the variety of possible solutions does not affect the dynamics of the overconstrained mechanism. This behaviour of the recursive formalism can be used to perform an on-line investigation of the static indeterminacy of a mechanism, including singular positions, where joint constraints are redundant only at one specific position.
The Development of Force-Deflection Relationships for Compliant Mechanisms
Authors: Howell Larry L. , Midha Ashok 
Published: March 2021

Abstract
The advantages of compliant or flexible link mechanisms include increased design flexibility and reduction in manufacturing time and cost. The analysis of such mechanisms may be difficult and time consuming due to the nonlinearities introduced by large deflections. Also, unlike rigid-body mechanisms, the type and form of motion of a compliant mechanism is dependent on the location and magnitude of applied loads. The pseudo-rigid-body model concept has been developed to simplify the analysis of compliant mechanisms by allowing them to be modeled as rigid-link mechanisms with springs. This work uses the principle of virtual work and the pseudo-rigid-body model concept to develop force-deflection relationships for compliant mechanisms. Several examples are presented, and general design equations are derived for pseudo-rigid-body four-bar and slider-crank mechanisms.
Form Feature Based Design of Turned Parts
Authors: Avasarala Pantulu V. , Stern Elliot L. 
Published: March 2021

Abstract
A form feature based modeller implemented on a personal computer is developed to design turned parts. The interactive environment provides the designer with a means of conveying the design intent and functionality without manipulating low-level graphics. Geometric defaults, tolerances, and warnings are embedded in the system and may be expanded for effective design for manufacture. The implementation of the modeller and usefulness of feature based design is discussed. This modeller is implemented in AutoLisp to run within AutoCAD.
Package Configuration for High Performance Storage and Retrieval of Cylindrical Components Robotically Assembled Into Large Structures in Space
Authors: Brewer W. V. 
Published: March 2021

Abstract
As the quantity of cylindrical components needed for in-space assembly grows to accommodate larger structures, so does the need for compact storage of these components during transportation to the site. Hex-Close-Pack is the ideal configuration for cylindrical parts. It offers a density increased by a factor of 4 compared to existing methods intended for robotic assembly.
Usual requirements for objects maneuvered on-orbit include: positive hold-down, positive hand-off, and package strength to withstand launch dynamic loads. The first two issues have been addressed with new manipulation techniques that are compatible with both robotic construction and compact storage. Packaging schemes that improve strength and are consistent with the new techniques are presented.
Pallet manipulation and storage are additional issues that are a function of package configuration. Pallet design can greatly reduce time and space required, for these tasks.
Information Needs in Agile Manufacturing
Authors: Candadai Arun , Champati Supratik , Herrmann Jeffrey W. , Minis Ioannis , Ramachandran Vijaysundar 
Published: March 2021

Abstract
In this paper we discuss the special information technology needed to support the emerging trend of agile manufacturing. Specifically, we address product data exchange standards, tools for efficient searches of product databases, and information models for the processing capabilities of manufacturing plants. The implementation of the product and plant information models is also discussed. Finally, we outline the role of these models in an ongoing study on the design-for-manufacture of electromechanical devices in an agile manufacturing environment.