bluuebunny/crossref_metadata_2025_split huggingface dataset:
Boundary Representation, Intersection, and Evaluation of Nurb Based Non-Manifold Objects
Authors: Wang Xuefu , Cheng Fuhua (Frank) , Sun Jiaguang , Barsky Brian A. 
Published: February 2021

Abstract
Boundary representation (B-rep), intersection, and evaluation schemes for NURB based non-manifold CSG objects are presented. The B-rep scheme follows a top-down, face-based approach. A definition of non-manifold objects and their set operations are given. The boundary evaluation process follows the intersect-merge-select strategy of Weiler (Weiler 1986). The generation of intersection geometry is performed in a bottom-up strategy. Intersection algorithms between entities of same and different dimensions are studied. The computation of face/face intersection is based on the concept of the marching method (Barnhill et al 1987; Barnhill & Kersey 1990). Several techniques have been developed to enhance the marching process, including the computation of initial points and tracing step sizes, control of intersection precision, and handling of branch points and tangential intersection curves (points). Inconsistency of the intersection results is corrected using criteria based on topological adjacency information. The proposed method finds all internal loops without performing loop detection (Hohmeyer 1991). New topological entities corresponding to the intersection results are created in the parameter space for each entity. These include vertices, edges and faces, but not 3D shells. The creation of topological faces is carried out by generating the boundary of each new face while traverse a net structure created during the intersection geometry generation process. Subsequent classification and selection are performed based on 2D topological entities, instead of 3D shells. The proposed methods has been implemented as the core of a NURB-based non-manifold modeling system.
Etch Rate Modeling in MEMS Design
Authors: Hubbard Ted J. , Antonsson Erik K. 
Published: February 2021

Abstract
This paper presents a model for determining the full three dimensional etch rate behavior of bulk wet etching of silicon from experimentally determined etch rates of four principal planes: (100), (110), (111), and (311). The etch rate for an arbitrary plane is expressed in terms of the measured planes. The model shows excellent agreement with both experimental measurements and values reported in the literature. For MEMS CAD to be able to accurately predict etched shapes, a high quality 3D model of etch rates such as the one reported here is required.
Design Considerations for Manufacturability of MEMS Comb Actuators
Authors: Dixit Hrishikesh , Taylor Dean L. , Kannapan Srikanth 
Published: February 2021

Abstract
Comb actuators are electrostatic drives commonly used in micro-electromechanical systems (MEMS). These devices are typically fabricated using standard Integrated Circuit (IC) fabrication techniques such as lithography, oxidation, chemical vapor deposition and etching. The design of MEMS devices such as comb actuators is a complex process due to the dimensionality of the parametric design space and the parametric interdependencies imposed by performance, manufacturability and reliability constraints. We present a study aimed at the decomposition and structured organization of the various design and manufacturability considerations for comb actuators. The value of this knowledge organization is illustrated by the formulation and solution of a design problem that ensures optimal parametric design and layout of a comb actuator on a silicon wafer. We combine analytical models and specialized fabrication “design rules” to obtain optimal solutions for two interesting problems in MEMS comb actuator design.
Systematic Process Selection in Mechanical Design
Authors: Esawi Amal M. K. , Ashby Michael F. 
Published: February 2021

Abstract
There has been a recent awareness of the importance of making the right manufacturing decisions early in the design process before the cost penalty of making changes becomes too high. The selection of the most appropriate manufacturing process — of which there are a very large number — is one such decision. It is commonly based on human-resident experience or on established local practice. As such, some potentially-usable processes may be overlooked. This paper explores ways in which process selection might be made more systematic.
It presents a procedure for manufacturing process selection which considers all manufacturing processes and eliminates the ones which cannot satisfy the design requirements. This is achieved using Process Selection Charts in which process capabilities are displayed graphically. A procedure for the ranking of the successful processes based on cost is under development.
The systematic selection procedure lends itself well to computer implementation. A database of manufacturing processes and an advanced user interface thus provide ideal support for designers. Cambridge Materials Selector (CMS) software is currently being applied to manufacturing process selection.
Toolpath Patterns and Their Evaluation Methods in NC Machining
Authors: You Xinnong , Chen Youping , Zhou Zude , Duan Zhengcheng 
Published: February 2021

Abstract
In this paper, various kinds of toolpath patterns are summarized and analyzed systematically for flat convex polygon, pocket with islands and sculptured surfaces. On this basis, the evaluation objectives of toolpath patterns are put forward, and a related fuzzy multi-objective evaluation model is presented to solve the problem of the assessment of alternatives with qualitative and quantitative criteria. At the end, an example of three toolpath patterns for the NC machining of a washer-wave-wheel is given to derive an optimal sorting sequence of them.
New CAD for Rapid Prototyping
Authors: Fukuda Shuichi , Suzuki Daisuke 
Published: February 2021

Abstract
We developed a new CAD tool with special attention paid to rapid prototyping. Most of the present 3-D CAD systems treat geometry with very high accuracy but it is not easy to define or modify geometry as we do in the earlier stages of design. The present CAD systems, we believe, are more oritented toward the detailed design and manufacturing of the final product.
As rapid prototyping itself is intended for the earlier stages of design, such a CAD system that permitts more easy or rough definition and modification of geometry is really desired. Most of the rapid prototyping systems generate 3-D geometry by piling up the 2-D sections layer by layer. So, if we develop such a layer-based CAD system, then we could more easily tranfer CAD data to the prototyping system.
Such an idea was very old, but the traditional ones cannot manipulate geometry with much ease. What we aimed here is to develop a system that a designer can manipuate geometry as freely as he or she wishes. Thus, our system serves as a preprocessor to the present 3-D CAD systems.
We are developing another system which permits to generate 3-D geometry as freely as if we are drawing it using a pen, based on the technology of 3-D measurement device. Couled with this system, the system we are proposing here is expected to tranfer such a 3-D geometry data very rapidly and easily to the prototyping equipment and also can interactively modify thus defined geometry data.
On Synthesis of Electro-Mechanical Assemblies
Authors: Madhusudan T. N. , Sycara Katia , Navin-Chandra D. 
Published: February 2021

Abstract
Research in providing feedback to designers to modify designs of electro-mechanical systems based on assembly and process plans has focused on identifying potential assembly and manufacturing problems during the design phase and providing suggestions to designers to eliminate them. Prototypical software systems provide design suggestions primarily based on the form of the different components in an electro-mechanical assembly thus providing feedback to the designers during the embodiment (form) design phase of the product. It is necessary to extend the feedback notions to other levels of abstraction describing a product i.e. function, behavior and parametric information. Performing such a task requires an understanding of the design process so as to have a better idea of the nature of feedback information required by a designer and its usage in design. In this paper, we outline a framework to integrate design feedback information in the course of the design task. This paper provides a classification of electro-mechanical products based on design requirements and describes a prototypical computational framework for the synthesis of electro-mechanical assemblies. We illustrate how assembly design (configuration design), parametric design and concept design may be integrated in a consistent manner.
“Modessa”: A Computer Aided Conceptual Design System
Authors: Kersten Twan 
Published: February 2021

Abstract
This paper describes the computer aided design system Modessa. Modessa is developed to support multi-disciplinary design teams in the conceptual design phase. Modessa is based on the “morphological design method” which decomposes the design problem into a number of so called functions. Then several alternatives are identified for each of these functions. These alternatives are visualized using pictures and arranged by function in a matrix which results in a so called “morphological overview”. Finally the alternatives are evaluated based on the customer requirements. The best alternatives for each function are combined to form the optimum solution for the design problem. Modessa supports multi-disciplinary design teams during the conceptual design process by:
- Suggesting known design alternatives for design functions, thus leaving more time for the creation of novel design alternatives.
- Offering a “common language” to objectively evaluate the design alternatives.
- Simplifying the creation and reuse of the conceptual design documentation.
Modessa is general purpose in nature and can be used for a wide variety of design applications. The kernel of Modessa is a design knowledge database that increases continuously as design teams add new functions (problems) and appropriate alternatives (solutions). In this paper the use of Modessa is illustrated by an industrial design example.
Team-Roles in Mechanical Design
Authors: Stetter Ralf , Ullman David G. 
Published: February 2021

Abstract
This paper presents an approach for identifying team-roles. The proposed approach is based on the interpretation of a design process in terms of the behavior of the members of the team. Behavior is codified in terms of the team member’s process and physical activities. In this study a collaborative design process was recorded on video-tape and analyzed in detail. The process was decomposed into distinct sections called events. In every event each team member was assigned a team-role taking into consideration the activity of the team member, i.e. what the team member does, how activity of the team member, i.e. what the team member does, how the team member does it, and the context of the event. A graphical representation of the results called ‘role-profile’ was developed making it possible to clearly identify a basic team-role for every subject in the observed design process.
Multi-Dimensional Mapping of Design Imprecision
Authors: Law William S. , Antonsson Erik K. 
Published: February 2021

Abstract
Preliminary design information is characteristically imprecise or fuzzy: specifications and requirements are subject to change, and the design description is vague and incomplete. The Method of Imprecision uses the mathematics of fuzzy sets to explicitly represent and manipulate imprecise preliminary design information, enabling the designer to better understand the full range of designs and performances that satisfy an imprecise set of specifications and requirements. This paper discusses the foundations of this methodology, and introduces pragmatic extensions that provide computationally tractable methods to map design imprecision from multiple design variables onto multiple performance variables. These methods attempt to minimize the number of function evaluations required while retaining an appropriate level of accuracy. This is achieved by using optimization to obtain extremal points for each performance variable and selectively applying a linear approximation for the mapping from the design variable space (DVS) to the performance variable space (PVS) to interpolate between extremal points. This linear approximation is constructed using regression techniques adapted from experiment design.
On a Mathematical Foundation of Axiomatic Design
Authors: Rudolph Stephan 
Published: February 2021

Abstract
The axiomatic design approach and its two underlying postulates, the independence and the information axiom, introduced by Suh (1990) are based on the fundamental claim that “there are generalizable principles that govern the design process and that these in the form of the design axioms are general principles or self-evident truths that cannot be derived or proven to be true except that there are no counter-examples or exceptions” (adapted from (Suh, 1994)).
This paper shortly describes a mathematical framework which allows replacing the independence and the information axiom with the so-called evaluation hypothesis (Rudolph, 1995a). This evaluation hypothesis is based on the technique of dimensional analysis known from physics and allows the straightforward derivation of expressions that in special cases match the above stated independence axiom. For the information axiom a different mathematical expression is obtained.
The new theoretical approach has the advantage of possessing an epistemological foundation in form of four fundamental requirements for the evaluation model of a design object which can be motivated through a rational thought process. The two different model assumptions are compared, discussed and illustrated using a published axiomatic design reference example.
Enhancing Design Education With Practical Knowledge Needed in Industry
Authors: Pattison Will 
Published: February 2021

Abstract
Education in design has become a major priority in modern mechanical engineering curriculums. In particular, design education has focused on using good design methodology to produce optimum solutions, promote innovation, and encourage creativity in the engineer. There are other facets of the design engineer’s position that should also be emphasized at the education level. First, design engineers must be aware of the manufacturing processes that will be used to turn their concepts into working solutions. Second, they must understand how prototypes of those solutions fit into the overall product development process, and how new technologies such as Rapid Prototyping can enhance it. Finally, they must be able to effectively communicate their design intent, both graphically, verbally, and in writing, at all stages of the product development process. These three essential engineering skills, with special emphasis given to the last two and their place in design education, are covered in this paper.
Design and Implementation of an Object-Oriented Cooperative Distributed Problem Solving Shell
Authors: Yang Feng-Chao , Ho Yu-Kuen 
Published: February 2021

Abstract
In this paper an Object-Oriented Cooperative Distributed Problem Solving Shell (OOCDPSS) is presented. It is a convenient and effective building tool for the cooperative multi-agent application systems under distributed computer environment. By the Distributed Artificial Intelligence technique and the Object-Oriented concept, each agent is constructed by multi-layer structure to reduce the design complexity and give more flexibility, and they are arranged as a recurrent group structure for run-time effective management. Additionally, the idea of mediator is adopted to integrate new information systems with the existing inflexible legacy system, and the distributed whiteboard agent is used for the information interchange among the agents. This prototype system has been completed and used as the test bed of our other laboratory projects.
Effects of Collocation on the Integrated Product Team and the Impact on Cost, Schedule, and Risk
Authors: Rumpf Richard L. , Gindele Mark E. 
Published: February 2021

Abstract
Program Managers need to look beyond the veil of potential benefits to assess the risks of contractor proposed concurrent engineering efforts. The mere mention of concurrent engineering or its synonym, integrated product team, does not in itself reduce program schedule and cost. Evaluations should center upon the offeror’s past success with these initiatives and the fundamental steps leading to their implementation.
In a recent study of several programs involving the manufacture of Aircraft Launch and Recovery Equipment (ALRE) and support equipment, the effects of integrated product teams were assessed. Several of the programs studied had been competitively awarded to contractors that subsequently defaulted on their contract. The equipment programs were then successfully manufactured by the Prototyping and Manufacturing department at Naval Air Warfare Center, Lakehurst, NJ.
Data from the study indicated the success of the manufacture was directly attributable to the use of integrated product teams. Extensive communication between engineering, manufacturing, and testing teams led to the resolution of problems quickly. Face to face meetings were frequent and issues were resolved in minutes without resorting to technical memorandums or other protracted written documents. Collocation of the team members was considered the most critical factor to gaining any benefits from concurrent engineering.
Further evidence indicated the more complex a system, the more collocation was critical to its successful completion. Complexity, when measured by the number of parts, critical interfaces, and final testing requirements, was assessed for each program. The more complex programs had employed more frequent and local communication.
A New Crossover Operator for Assembly Sequence Planning by Genetic Algorithms
Authors: Sebaaly Milad Fares , Fujimoto Hideo 
Published: February 2021

Abstract
Assembly Sequence Planning (ASP) is the generation of the best or optimal sequence to assemble a certain product, given its design files. Although many planners were introduced in research to solve this problem automatically, it is still solved manually in many advanced assembly firms. The reason behind this is that most introduced planners are very sensitive to large increases in product parts. In fact, most of these planners seek the exact solution, while performing a part basis decision process. As a result, they are trapped in tedious and exhaustive search procedures, which make them inefficient and sometimes obsolete. To overcome these difficulties, Sebaaly and Fujimoto (1996) introduced a new concept of ASP based on Genetic Algorithms application, where the search procedure is performed on a sequence population basis rather than a part basis, and a best sequence is generated without searching the complete set of potential candidates. This paper addresses the problem of improving the GA performance for assembly application, by introducing a new crossover operator. The genetic material can be divided and classified as ‘good’ or ‘bad’. The new crossover insures the maximum transmission of ‘good’ features from one generation to another. This results in a faster GA convergence. The performance of the new algorithm is compared with that of the ordinary matrix crossover for a modified industrial example, where it proved to be faster and more efficient.
Assembly Modeling and Analysis of Integral Fit Joints for Composite Transportation Structures
Authors: Lee David E. , Hahn H. Thomas 
Published: February 2021

Abstract
In order to reduce assembly complexity and enhance the performance of structural elements utilized in transportation systems, a novel approach is presented that uses integral fit joints in the assembly of fiber-reinforced composite structural elements. While the application of composite materials in transportation structures is not new or unique, their use coupled with integral fit joint designs affords a multi-magnitude reduction in the number of components required to assemble transportation systems. Essential to this effort is the need to effectively model and analyze the composite integral fit joint specifically focused on assembly. This paper introduces pertinent issues in the design and assembly of transportation systems, the assembly of their structural joints, and defines assembly models and analysis methods for composite integral fit (CIF) joints.
A Critical Review of Tube and Sheet Metal Hydroforming Technology
Authors: An Jian , Soni A. H. 
Published: February 2021

Abstract
The hydroforming technology, which is rapidly gaining popularity in the sheet metal and tube forming industry is reviewed. The features and the characteristics of the hydroforming process are described. The uniformly distributed fluid pressure covers the back side of the sheet as a die generates many advantages in the technical point of view as improving the part surface quality, reducing the forming severity and smoothing the thickness distribution. The benefits of using hydroforming technology are examined and analyzed in a technical level. The better part quality, less cost of tooling, materials saving and part weight reduction can be achieved using the hydroforming technology. The design methodologies for the hydroforming process parameters are reviewed and discussed in a certain detail. Computer-aided-engineering such as finite element simulation is suggested for such process parameter design.
The Integration of a SMT Fully-Automated Rework Cell for Fine-Pitch Surface Mounted Devices
Authors: Fidan Ismail , Ruff Larry , Derby Stephen 
Published: February 2021

Abstract
Surface mounted components have become the choice of the electronics manufacturing industry to solve problems in the complex circuit boards. New components using increased lead counts on finer pitches make manufacturing difficult. The increased complexity, cost, and lead count of the Surface Mount Technology (SMT) components, and also the increasing compactness of the SMT assemblies have demanded the creation of newer rework tools as an essential part of electronics manufacturing. Therefore, it becomes essential to have a well-controlled process to assure that rework is not only possible but that it is consistent and flawless. Automation is the common answer to achieve both efficiency and quality. This paper describes a system for the automated rework of fine pitch components that is under development as part of the Center for Integrated Electronics and Electronics Manufacturing (CIEEM) at Rensselaer.
Explicit Solution for the Forward Displacement Analysis of the Stewart Platform Manipulator
Authors: Jin Yao , Hai-Rong Fang 
Published: February 2021

Abstract
A method is presented to directly solve the problem of the forward displacement analysis of the Stewart platform manipulator. With algebraic elimination and the use of only one extra sensor, the explicit expressions on the forward displacement solution is obtained so that the method may enable designers to get the best compromise between the supplementary cost and complexity of the manipulator and the computation time for solving the forward displacement analysis. A numerical example is given to illustrate the method presented.
Orientation Capability and Robot Wrists
Authors: Holland Neil , Dai Jian S. , Kerr David R. 
Published: February 2021

Abstract
This paper introduces a measure of the orientation capability of manipulator wrists, and a means of representing orientation capability. Wrists with the various combinations of roll, pitch and yaw joints, with one, two or three joints are studied. It is shown that for all non-degenerate orthogonal three joint wrists, the image space representing the orientation capability is doubly-covered, and the possibilities for restricting joint angles to make it singly-covered are given. Degenerate postures for each configuration are also given, and singularity-free wrists with three joints are discussed.