bluuebunny/crossref_metadata_2025_split huggingface dataset:
Geometric Tolerance Analysis for Mechanism Design
Authors: Tsai Jhy-Cherng 
Published: February 2021

Abstract
Manufacturing tolerances and joint clearances are the two major factors affecting mechanism accuracy. As error analysis is one of the bottlenecks of precision machinery design, methods for geometric tolerance analysis must be investigated for mechanism design. This paper describes an approach for analyzing errors caused by geometric tolerances and clearances in mechanism design. The method consists of three parts: variational kinematic models for geometric tolerances, a systematic geometric dimensioning and tolerancing (GD&T) representation scheme, and computation methods for interval and statistical tolerances. Variational models are based on differential transformation to model kinematic errors caused by tolerances and clearances. The model is consistent with error models used in typical mechanical devices. The GD&T scheme, called the Tolerance Network (TN), employs graph theory for representing GD&T as well as fitting specifications of a design is described. Errors are propagated by traversal throughout the network and stack-up of these variational models along the dominate path in the TN. Error computation methods for both interval and statistical tolerance types are discussed. A method for computing central moments, rather than analytical distributions, of statistical tolerances is developed to reduce the computation complexity. A five-degree-of-freedom robot is used as an example at each step to illustrate this approach.
Variant Shape Model Applicable to Combined Geometric Tolerances
Authors: Inoue Keisuke , Okano Akira 
Published: February 2021

Abstract
This paper describes a variant shape model and its application to tolerance analysis. To realize a high-precision mechanism at low cost, designers specify various types of tolerances selectively, often in combination on a single face.
We propose a solid model that has attributes at points scattered over its faces. In this model, the macroscopic geometry is represented as a B-rep solid model, and the microscopic geometry (manufacturing errors and clearances) as attributes. The model can represent a wide variational class, such as shapes with form errors. We use it to present a method for generating a deviant shape model having a specified set of geometric errors.
After deviant part shapes have been generated, they are assembled virtually in such a way that they do not interfere with each other and that the physical conditions of the attachment are satisfied. Through a large number of deviant assemblies, a product’s performance is analyzed statistically and quantitatively.
Optimization of Deep Drawing Processes Using Statistical Design of Experiments
Authors: Bauer Dietrich , Krebs Regine 
Published: February 2021

Abstract
For a deep drawing process some important controllable variables (factors) upon the maximum drawing force are analyzed to find a setting adjustment for these process factors that provides a very low force for the metal forming process. For this investigation an orthogonal array L18 with three-fold replication is used. To find the optimum of the process, the experimental results are analyzed in accordance with the robust-design-method according to Taguchi (Liesegang et. al., 1990). For this purpose, so-called Signal-to-Noise-ratios are calculated. The analysis of variance for this S/N-ratios leads to a mathematical model for the deep drawing process. This model allows to find the pressumed optimal settings of the investigated factors. In the following, a confirmation experiment is carried out by using these optimal settings. The maximum drawing force of the confirmation experiment does not correspond with the confidence interval, which was calculated by analysis of variance techniques. So the predicted optimum of the process does not lead to a metal forming process with very low deep drawing force. The comparison with a full factorial plan shows that there are interactions between the investigated factors. These interactions could not be discovered by the used orthogonal array. Thus the established mathematical model does not describe the relation between the factors and deep drawing force in accordance with the practical deep drawing conditions.
Genetic Algorithm Based Optimal Planning Method of Energy Plant Configurations
Authors: Fujita Kikuo , Akagi Shinsuke , Yoshida Kiyotaka , Hirokawa Noriyasu 
Published: February 2021

Abstract
A genetic algorithm based optimization method is proposed for the planning problem of energy plant configurations. In such a planning problem, a plant configuration, i.e., types, models, and numbers of equipment, is determined so as to satisfy required energy demand conditions and to minimize the sum of plant facility cost and input energy cost. This is a combinatorial optimization problem similar to the knapsack problem, which is hard to find an optimal configuration for due to the huge number of alternatives. In this paper, we apply a genetic algorithm to such an optimal planning problem by representing a plant configuration with bit vectors and by arranging cost functions so as to keep search performance superior against the deceptive problem. The method is implemented on a symmetric shared-memory, multi-CPU workstation, where almost linear speedup is accomplished. Its performance is demonstrated by computational examples of a cogeneration plant and comparison results with a random search and a simulated annealing method.
Spot Weld/Adhesive Pattern Optimization
Authors: Yang R. J. , Rui Y. , Mohammed A. , Singh G. 
Published: February 2021

Abstract
This research presents a new application of topology optimization. Patterns for spot weld location and adhesive distribution when joining body panels are determined by using the topology optimization method. The density method which parameterizes the density of each finite element is employed and a sequential linear programming method is used for solving the topology optimization problem. In this study, a B-Pillar to Rail Joint exemplifies the design methodology. The results show that patterns for optimal spot weld location and adhesive distribution can be obtained for a maximum stiffness design with mass constraints.
Packing of Generic, Three-Dimensional Components Based on Multi-Resolution Modeling
Authors: Kolli Ashish , Cagan Jonathan , Rutenbar Rob 
Published: February 2021

Abstract
A method of optimizing layouts of three-dimensional objects of arbitrary geometry with simulated annealing is presented in this paper. Using multi-resolution models, this approach is able to generate optimal layouts of three-dimensional objects in reasonable time. An example of packing highly non-convex objects illustrates the power of this method.
Generalized Abbe Principle: Position Error Propagation in Machine Elements
Authors: Pegna Joseph 
Published: February 2021

Abstract
In the quest for ever finer levels of technology integration, mechanical linkages reach their precision limits at about 5micrometers per meter of workspace. Beyond this physical limit, all six dimensional degrees of freedom need to be precisely ascertained to account for mechanical imperfections.
This paper substantiates Wu’s vision of “precision machines without precision machinery.” A formulation and statistical characterization of position and orientation error propagation in rigid bodies are presented for two extreme models of measurement. It is shown that error distribution is uniquely dependent upon the design of the measurement plan. The theoretical foundations presented were evolved in the course of designing precision machinery. Other potential applications include: fixture design, metrology, and geometric tolerance verification.
Foraging-Directed Adaptive Linear Programming: An Algorithm for Solving Nonlinear Mixed Discrete/Continuous Design Problems
Authors: Lewis Kemper , Mistree Farrokh 
Published: February 2021

Abstract
Design models often contain a combination of discrete, integer, and continuous variables. Previously, the Adaptive Linear Programming (ALP) Algorithm, which is based on sequential linearization, has been used to solve design models composed of continuous and Boolean variables. In this paper, we extend the ALP Algorithm using a discrete heuristic based on the analogy of an animal foraging for food. This algorithm for mixed discrete/continuous design problems integrates ALP and the foraging search and is called Foraging-directed Adaptive Linear Programming (FALP). Two design studies are presented to illustrate the effectiveness and behavior of the algorithm.
The Effect of a Fractal Profile Tolerance on the Dynamic Performance of Cams
Authors: McAdams Daniel A. , Wood Kristin L. 
Published: February 2021

Abstract
To ensure a successful design, it is important to understand the effect that design parameters have on design performance. Tolerances are an important subset of design parameters. In this paper, the relevance of fractal surface characterization for profile tolerances is investigated. The notion of fractal geometry is discussed. The validity of a fractal characterization on a cam surface is determined. Dynamic simulations of a cam-follower system are used to qualify the effect of a fractal profile error on system performance.
A Knowledge-Based System for Machining Operation Planning in Feature Based, Open-Architecture Manufacturing
Authors: Stori James A. , Wright Paul K. 
Published: February 2021

Abstract
Within the Integrated Design And Manufacturing Environment (IMADE), operation planning provides a mapping from geometric design primitives to machining operation sequences for manufacturing processes. Operation planning includes tool selection, machining parameter selection, and tool path generation. An object oriented approach to program structure is adopted, whereby features, operations and tools, inherit behaviors and attributes from the appropriate class-hierarchies for the part, the manufacturing operations, and tooling classes. A detailed example is presented illustrating the operation planning search algorithm. Scripts are generated by the individual machining operations for execution on a machine tool. Tooling information is maintained in an object-oriented database through the FAR libraries for Common LISP. Examples of particular process plans show that the inherent trade-offs between specified precision and machining time can be investigated. An Open Architecture Machine Tool (MOSAIC-PM) has been used to machine the parts created by the feature based design and planning system. The novel contributions of this paper relate to the demonstration of “seamless” links between, a) design, b) planning, and c) actual fabrication by milling.
Manufacturability Analysis Using High-Level Process Planning
Authors: Herrmann Jeffrey W. , Lam Giang , Minis Ioannis 
Published: February 2021

Abstract
Virtual enterprises utilize the resources of the most capable partners for mutual benefit. This paper describes a high-level process planning and manufacturability analysis approach which increases decision support at the product design stage and reduces time to market by integrating the process of forming the virtual enterprise with design critiquing and process planning so that the designer can develop the process plan and evaluate the design with respect to the capabilities of the potential partners early in the design cycle. Alternative high-level process plans are generated based on the product design requirements, process capabilities, and plant performance measures. The manufacturability of each design-process plan combination is evaluated by estimating the cost, lead time, and expected quality of each high-level process plan.
Compact 2D Pattern Development From 3D Polygonal Surfaces
Authors: Wang Cheng-Hua , Bourne David A. 
Published: February 2021

Abstract
Pattern development involves mapping 3D surfaces into 2D flat patterns. To reduce the complexity of patterns, approximations of the surfaces into polygonal surfaces such as quadrilateral or triangular facets are usually necessary. This paper is concerned with the pattern development of polygonal surfaces with a special reference to bent sheet metal parts. The development process needs to consider the unfoldability of 2D patterns. The unfoldability requires that the 2D pattern does not overlap itself, and the faces of the part do not distort during bending. For some designs, there are multiple 2D patterns that can all be bent into the same 3D shape. The compact pattern is usually selected due to better stock utilization in cutting and nesting and ease of handling during bending. We show that the development of the compact 2D pattern can be converted into a minimum cost spanning tree problem. This approach has been implemented using an A* search algorithm and several examples are presented.
A Coordinated Product and Process Development Environment for Design for Assembly
Authors: Lee David E. , Hahn H. Thomas 
Published: February 2021

Abstract
The development approach embodied in design for assembly (DFA) has been demonstrated effectively in different industrial sectors and through the design of a multitude of products. However, little effort has been applied to improving development methods for the assembly operations and processes used to fabricate these products. If the benefits of concurrent engineering are to be fully realized, a more holistic approach to unifying a product’s design with development of its assembly processes is needed. This paper provides a description of our approach to establishing an environment for coordinated product and assembly process development. The steps in a product’s development cycle are introduced and the concepts of design for assembly and concurrent engineering defined. Using DFA methods as a motivation, an approach to assembly process development is derived. Referred to as Systematic Assembly Process Development (S-APD), assembly processes are defined and analyzed by using standardized generic assembly operations. To address problems created by using concurrent engineering in product/process development, two mechanisms are described. Since the focus of developing a product (i.e. how well does it perform and cost) differs from developing its assembly processes (i.e. making products at the necessary volumes), the concept of an interface reference context is introduced as a coordination mechanism and applied to development of unmanned composite low-cost aircraft. Moreover, in identifying which elements of the design are to be assembled with a specific set of production technologies, a synchronous thread is instantiated to link product and assembly process development efforts in a temporal context. Different approaches are reviewed to resolve potential conflicts related to concurrency effects generated during simultaneous product and assembly process development.
Enabling Digital Mock-up With Virtual Reality Techniques: Vision, Concept, Demonstrator
Authors: Dai Fan , Reindl Peter 
Published: February 2021

Abstract
Mock-ups and prototypes are very important for design evaluations. In the automotive and aeronauic industries, CAD and CAE systems are used more and more. There is a strong attempt to replace a great part of mock-ups with digital models — the so called Digital Mock-Ups. Many companies have started to evaluate existing tools and technologies, and think about, or begin to develop virtual prototyping systems for their own needs. In this paper, we present the idea of Digital Mock-Up which is developed within the ESPRIT project AIT - Advanced Information Technologies in Design and Manufacturing1, and show the vision of virtual prototyping — the use of virtual reality techniques for Digital Mock-Up, based on the AIT-DMU-demonstrator.
Distance Learning of Skills
Authors: Fukuda Shuichi , Matsuura Yoshifusa , Wongchuphan Premruedee , Takahashi Tokiko 
Published: February 2021

Abstract
With the increasing globalization and expansion of the people’s activities, distance learning is getting wide attention. Distance learning is not a computer aided education system alone. What is important is that collaboration over the network is a prerequisite for that, so that the technology developed there will be easily utilized for distance manufacturing and other collaborative activities over the network.
When we come to think of integrating design and manufacturing over the network, the problem of skill comes up. Skill plays a very important role in manufacturing. But most of the systems developed so far have been focusing their chief attention toward how rigously they can represent design and manufacturing knowledge and experience in terms of symbols, and non-symbolic approaches are still few.
It is believed that motion occupies a large portion of skills, but the present systems being such, and in additon, such media as TV, video, etc are one way from a teacher to a student so that it is still very difficult to learn skills over the network, since skill learning requires much interactive processes. Otherwise, students find it very difficult what part of the model motion they should concentrate their focuses.
If a teacher can edit the motion of a student and a student can watch how his or her motion is edited, the student will understand more easily what is wrong with his or her motion., and can identify where his or her attention should be focused.
Based on this idea, we have developed a preliminary system for distance learning of skills to demonstrate the effectiveness of the approach.
Industrial Applications of Conceptual Robustness
Authors: Chang Tzyy-Shuh , Ward Allen C. , Schmidt Jason W. , Stenman Michael A. 
Published: February 2021

Abstract
We have introduced the idea of conceptual robustness to formalize distributed concurrent engineering (Chang, et al., 1994; Chang and Ward, 1995a) and design-in-modularity (Chang and Ward, 1995b). This paper reports two industrial applications of conceptual robustness, one for distributed concurrent engineering and the other for modular design. The formulations delivered satisfactory solutions to both cases.
Classifying Functions for Mechanical Design
Authors: Kirschman C. F. , Fadel G. M. , Jara-Almonte C. C. 
Published: February 2021

Abstract
As design methods are studied, the usefulness of function-based methodologies becomes clear. However, for these methodologies to be fully utilized, there must be some standardization of the functions used to provide a common language. This paper presents a proposed taxonomy of elemental mechanical functions which can be used with many decomposition techniques. The taxonomy can be used as a pedagogical tool or as a basis for the derivation of a complete taxonomy.
Design for Assembly Techniques in Reverse Engineering and Redesign
Authors: Lefever Douglas D. , Wood Kristin L. 
Published: February 2021

Abstract
Design for Assembly (DFA) is the process by which a product is designed to be easily assembled. Such design simplifications are accomplished through reducing the number of operations required to assemble the product, improving the handling of each component, and/or modifying the required operations (insertion, joining, etc.). There exist several techniques for assessing the assemblability of a design through an analysis of these three aspects. However, there also exists a clearly defined need for evolving such techniques to indicate how a product should be redesigned with respect to customer needs and associated functionality. This paper presents three such evolutions, aimed at reducing the number of components in an assembly during redesign. The first technique is a component elimination procedure, the second technique is a component combination analysis, and the third technique establishes a logical approach for revealing more abstract component elimination or combination opportunities. These three DFA techniques are integrated within a reverse engineering and redesign methodology. They are then applied to a industrial design application, i.e., redesign of an auxiliary automobile visor. Results demonstrate definitive part count reduction, while maintaining and improving design functionality.
Principles From Toyota’s Set-Based Concurrent Engineering Process
Authors: Sobek Durward K. , Ward Allen C. 
Published: February 2021

Abstract
A five-year study reveals that the highly successful Toyota Motor Corporation seems to follow a different paradigm of design than other US and Japanese auto companies. This paper outlines 11 principles that appear to form the foundation of Toyota’s use of “Set-Based Concurrent Engineering.” Discussion of the principles includes illustrations from Toyota.
Validation Studies of an Information-Flow Model of Design
Authors: Christian Andrew D. , Grasso Kamala J. , Seering Warren P. 
Published: February 2021

Abstract
This paper describes results obtained from an information-flow model of the design process. The model represents design projects as tasks to be accomplished and information to be exchanged. An event-based simulation uses computer agents to represent engineers working on the design project within a virtual office environment, exchanging information, and making decisions. The first of two validation studies presented in this paper uses corporate records and timesheet data to construct a model and compare simulation results with actual project results. The second study evaluates the ability of a manager unfamiliar with the software to set up a model of a design project and to gain useful insights by exercising the model.
An Analysis of Multiple Peg-in-Hole Insertion Tasks
Authors: Sturges Robert H. , Sathirakul Korntham 
Published: February 2021

Abstract
In this paper an analysis of the physics of a multiple peg-in-hole assembly task is addressed. Insertion of three pegs, arranged in an equilateral triangle, into three holes simultaneously is chosen as an example case. Although a 3 dimensional problem, the small-angle assumption reduces the model to only 3 degrees of freedom: 2 translations in the XY plane and a rotation about the Z axis. The multiple-pegs are viewed as points in a 3 dimensional configuration-space (C-space.) The net force and torque due to contact during chamfer crossing at each point in the C-space are determined. It is shown that the net force and torque are in the directions of minimizing the lateral and angular errors of the pegs. Based on these data together with compliance models of Remote-Center Compliance (RCC) and Spatial RCC (SRCC), the force and torque that occur during multiple-peg insertion using these passive devices are predicted. The result from the prediction is used to compare the performance of the two devices, and to design strategies for successful insertion of this assembly task.