bluuebunny/crossref_metadata_2025_split huggingface dataset:
Probabilistic Tolerance Allocation for the Dynamics of an Internal Combustion Engine With a Flexible Connecting Rod
Authors: Zhang F. , Gilmore B. J. , Sinha A. 
Published: February 2021

Abstract
Tolerance allocation standards do not exist for mechanical systems with flexibility and whose response are time varying, subjected to discontinuous forcing functions. Previous approaches based on optimization and numerical integration of the dynamic equations of motion encounter difficulty with determining sensitivities around the force discontinuity. The Alternating Frequency/Time approach is applied here to capture the effect of the discontinuity. The effective link length model is used to model the system and to account for the uncertainties in the link length, radial clearance and pin location. Since the effective link length model is applied, the equations of motion for the nominal system can be applied for the entire analysis. Optimization procedure is applied to the problem where the objective is to minimize the manufacturing costs and satisfy the constraints imposed on mechanical errors and design variables. Examples of tolerance allocation are presented for a single cylinder internal combustion engine with a flexible connecting rod.
GAPRUS: Three-Dimensional Pipe Routing Using Genetic Algorithms and Tessellated Objects
Authors: Sandurkar Sunand , Chen Wei , Fadel Georges M. 
Published: February 2021

Abstract
Pipe routing is the technique of developing collision-free routes for pipes between two locations in an environment scattered with obstacles. In the past, research has been primarily focused on the use of deterministic optimization techniques to derive the optimal route. Computational efficiency of deterministic techniques is low for highly nonlinear and sometimes discontinuous problems like the pipe routing problem. Besides, due to limitations in the representation of 3-dimensional geometry, the shapes of obstacles have been restricted to primitives. In this paper we present a novel approach to overcome these limitations.
A non-deterministic optimization approach based on Genetic Algorithms is proposed to generate pipe routing solution sets with a high computational efficiency. Representation of the objects and pipes in the tessellated format offers huge benefits in computation as well as adaptability. We demonstrate the versatility of our approach and its ability to accommodate and solve problems involving 3-D freeform obstacles.
Fine Tuning of Rational B-Splines Motions
Authors: Srinivasan Lakshmi N. , Ge Q. Jeffrey 
Published: February 2021

Abstract
This paper presents two algorithms for fine-tuning rational spatial motions suitable for Computer Aided Design. The rational motions are represented by rational B-spline curves in a projective dual three-space known as the Image Space of Spatial Kinematics. The problem of fine-tuning of rational motions is studied as that of fine-tuning the corresponding rational curves in the Image Space called the image curves. The path-smoothing algorithm automatically detects and smoothes out the third order geometric discontinuities in the path of a cubic rational Bspline image curve. The speed-smoothing algorithm uses a quintic rational spline image curve to obtain a second-order geometric approximation of the path of a cubic rational B-spline image curve while allowing specification of the speed and the rate of change of speed at the key points to obtain a near constant kinetic energy parametrization. The notion of kinetic energy is used in the paper as a natural way of combining the rotational and translational speed of a spatial motion. The results have applications in trajectory generation in robotics, planing of camera movement, spatial navigation in visualization and virtual reality systems, as well as mechanical system simulation.
Tolerance Analysis in System Design Based on Multiobjective Optimization
Authors: Rai Sudhendu , Jackson Mark 
Published: February 2021

Abstract
This paper addresses the problem of robustness in the design of engineering systems in which design parameters and multiple performance criteria are coupled with each other. The problem of analyzing the robustness of such systems that simultaneously involve multiple performance criteria is formulated and solved.
The inverse problem of allocating optimal variabilities on design parameters that will yield acceptable robustness in performance is formulated as a multi-objective optimization problem. A direct approach of generating solutions is described and applied to the xerographic problem of allocating to functional parameters such that the performance variability in print output is within acceptable limits.
Survey of Process Planning Techniques for Layered Manufacturing
Authors: Marsan Anne , Dutta Debasish 
Published: February 2021

Abstract
This paper focuses on process planning for LM and provides a survey of techniques developed to date. Process planning is performed to generate the tool paths and process parameters for an object that is to be built by a particular LM process. The steps required are: part orientation, support structure generation, slicing, path planning, and process parameter selection. STL files, solid models, and image and reverse engineering data are all considered as possible input to the process planning system. The techniques reviewed can be used for a variety of LM systems.
Integrating I-DEAS With Remanufacturing and Assemblability Assessments
Authors: Kalyan-Seshu Uma-Sankar , Bras Bert 
Published: February 2021

Abstract
A growing concern about the environment, and especially about waste and landfill, has motivated research into environmentally conscious design and manufacturing approaches. This has placed new burdens on designers. In order to aid designers in their new tasks, one of our objectives is to minimize the gathering of information and maximize the utility of existing design information. In the research discussed in this paper, the specific objective is to enable the quantification and enhancement of product remanufacturability. Guidelines for integrating some of the commercially available CAD packages (like I-DEAS, Pro/ENGINEER, CATIA) to remanufacturing assessments, and ways to use the input information to these assessments for making other assessments (like assemblability) are developed. A number of case studies are given to illustrate the approach. Our long term goal is to identify the minimum amount of information needed to do effective design for the life-cycle.
Ruled Surfaces, Lie Groups, and Mesh Generation
Authors: Sprott Kenneth , Ravani Bahram 
Published: February 2021

Abstract
This paper develops a method for design of Beziér and B-spline ruled surfaces taking advantage of the Lie group structure associated with the displacement of lines. The result is a computational method which is independent of the choice of coordinate system. The method is unique in that it can be used on a set of intersecting lines and in this way is applied to automatic mesh generation for finite element analysis.
Robust Design for Mechanism Balancing
Authors: Li Zhe 
Published: February 2021

Abstract
The sensitivity formulae of the shaking force and shaking moment of general planar articulating mechanisms are derived. A planar four-bar mechanism is taken as a numerical example. The sensitivity and robustness of the complete force balancing result and the optimum force and moment balancing result to the link mass parameters are analyzed separately. A new robust balancing method that is insensitive to the processing errors is presented.
Goal-Based Configuration Design of Fluid Power Systems Using Neural Networks
Authors: Potter Stephen , Chawdhry Pravir , Culley Stephen , Burrows Cliff 
Published: February 2021

Abstract
In this paper, we present a machine learning goal-based methodology for producing configuration designs of fluid power systems. The goal is to produce solution(s) that provide the functionality desired by the user. This methodology allows the construction of an automated tool for producing the designs based on machine learning techniques, specifically artificial neural networks. In order to do this, the set of functional elements that constitute the user requirements must be recognised, as must the elements of the solution space. These sets are described in what is a necessarily context-sensitive method of producing valid mappings from the requirements set to the solution space.
The neural networks are applied to extract and encapsulate the necessary design knowledge from examples of good designs, and in doing so, overcome one of the principal problems associated with previous attempts to build automated configuration design tools, namely that of knowledge acquisition. The problem of specifying the time-varying functional requirements was addressed by the adoption of a Time Delay Neural Network algorithm.
Two examples are presented as design test cases. The results show that it is possible to construct a configuration design tool based on the methodology and incorporating domain-specific design knowledge in the form of trained neural networks.
Information Requirements for the Support of Assembly Mating Conditions
Authors: Henson Brian W. , Juster Neal P. 
Published: February 2021

Abstract
This paper presents an analysis of the requirement to be able to exchange or share data about assembly mating conditions between different computer systems. The challenge is that although drawing and solid model data can be exchanged between different systems, there are currently no methods of exchanging data about assembly mating conditions. A brief assessment of existing data exchange technologies is presented, the benefits of a canonical representation for mating conditions are discussed, and some of the information requirements that need to be satisfied are detailed. The requirement for a canonical representation is illustrated with a data model that satisfies the information requirements. An example of the use of the data model to describe a mating condition is presented.
Direct Manipulation of Planar Geometry
Authors: Fukuda Shuichi , Asano Tatsuya 
Published: February 2021

Abstract
Most of the presently available CAD systems are oriented toward generating the geometry of a whole product. But if we consider the problem of manufacturing, we sometimes wish to have such a CAD system that permits us to decompose the geometry of a final product so that we may make adequate decisions how to assemble pieces into the final shape.
For example, if we consider welding, the decision where to weld does not necessarily reflect the welding engineers’ knowledge and experience. Rather, it is determined from other considerations such as design, mechanical machining, etc. But if we could take some portion of welding engineer’s knowledge and experience at the earlier stages of design, designers might change this design to make welding much easier to perform or to permit larger degree of allowances for mechanical machining, since large amount of heat will be inputted there later on by welding. Thus, a CAD system that permits such a decomposition of geometry is desired in order to integrate design and manufacturing and to achieve true concurrent engineering.
In this work, a preliminary system has been developed which allows direct manipulation of only planer geomtry. But to consider that we do not have adequate systems which allow such decomposition for planer geometries and we still use CAD systems to work on a final geometry and different systems to determine the optimum plate cutting out of a large plate and further some other different systems to verify that the section to be welded will have enough strength, such a system would provide a first step toward realizing real concurrent engineering. Because there are many cases in welding where only planer geometries are used and if a final geometry can be decomposed into planer geometries, we would know that where it would be better to weld or how we can put them together.
Shape Grammars and Their Languages: A Methodology for Product Design and Product Representation
Authors: Agarwal Manish , Cagan Jonathan 
Published: February 2021

Abstract
This paper argues that shape grammars and the languages they define are an ideal means to generate and represent products where basic functionality can be decomposed into discrete processes, forms can be created to fulfill those functional processes, and variation in those forms differentiates between competitive products. A shape grammar for the design of coffee makers is highlighted and used to illustrate how an infinite set of a class of products can be articulated through a concise shape grammar. Novel coffee makers and coffee makers in the market today are generated from the grammar.
Customer Metrics for the Selection of Generic Forms at the Conceptual Stage of Mechanical Design
Authors: Kirschman C. F. , Fadel G. M. 
Published: February 2021

Abstract
Customer satisfaction is critical to product success. Yet evaluation methods that directly consider the customer’s wants and that are applicable at various stages of the design process are few. This paper proposes three metrics that provide the designer with a means to evaluate designs based on customer attributes: Pleasure, Protection, and Inverse Cost (Icost). These metrics are general enough to be used in conceptual design but broad enough to evaluate finished products. In addition to describing the metrics in detail, this work describes how they are used to provide a selection technique for choosing generic forms to fulfill functions at the conceptual stage of mechanical design. At this stage, there are often many alternatives to select from based on a large number of attributes. This technique uses the new metrics in combination with an adaptation of the utility theory to provide a means for the designer to organize the information and choose between alternatives while maintaining a customer viewpoint.
A Probabilistic-Based Design Model for Achieving Flexibility in Design
Authors: Chen Wei , Yuan Chenhao 
Published: February 2021

Abstract
In the early stages of product development, the transformation between design requirements and design solutions often involves uncertainties when specifying the desired target value for the performance expressed in design requirements. Additionally, to provide flexibility for later development, the design solution obtained is desired to be a range rather than a single solution. Our primary focus in this paper is on developing a probabilistic-based design model as a basis for providing the flexibility that allows designs to be readily adapted to changing conditions. This is obtained by developing a range of design solutions which meet a ranged set of design requirements. Meanwhile, designers are allowed to specify the varying degree of desirability of a ranged set of design requirements based on their preferences. The Design Preference Index (DPI) is introduced as a design metric to measure the goodness of flexible designs. Providing the foundation to our work are the probabilistic representations of design performance, the application of robust design concept, and the utilization of the compromise Decision Support Problem (DSP) as a multi-objective decision model. A two-bar structural design is used as an example to demonstrate our approach. Our focus in this paper is on introducing the probabilistic-based design model and not on the results of the example problem, per se.
Multiobjective Optimization and Quantitative Trade-Off Analysis in Xerographic System Design
Authors: Rai Sudhendu 
Published: February 2021

Abstract
A complex engineering system such as a xerographic marking engine is an aggregate of interacting subsystems that are coupled through a large number of constraints and design variables. The traditional way of designing these systems is to decouple the overall design into smaller subsystems and assign teams to work on these subsystems. This approach is critical to making the project manageable and enabling concurrent development. However, if the goal is to design systems that can deliver best possible performance, i.e. if the performance limits are being pushed to the extreme, characterizing the interactions becomes critical.
Multiobjective optimization is a design methodology that addresses the issue of designing large systems where the goal is to simultaneously optimize a finite number of performance criteria that come from one or more disciplines and are coupled through a set of design variables and constraints. This approach to design makes explicit and quantitative the inherent tradeoffs that need to be made in doing coupled system design. It also enables the determination of the attainable limits of performance from a given system.
This paper will discuss the multiobjective optimization methodology and optimal methods of performing quantitative trade-off analysis. These design methods will be applied to problems from the xerographic design domain and results will be presented.
Design for Purchasing: A Methodology for Reducing the Materials Cost of Engineered Products
Authors: Bradley Stephen , Calice Matthias , Fischer Marc , Harmening Michael 
Published: February 2021

Abstract
This paper gives an overview of a methodology for reducing the cost of purchased materials for engineered products. The methodology has been successfully employed for a wide range of applications, ranging from low value-added products, such as simple processed materials (e.g., steel sheet or profiles), to high value-added equipment, such as machine tools and major components of industrial plants. We have applied the methodology in some 80 projects, achieving cost savings averaging 17% on top of the 10% savings achieved using traditional purchasing optimization approaches. The key distinguishing features of the methodology are a product-oriented as opposed to materials group-driven approach, the establishment of interdisciplinary teams that include engineers and purchasing professionals, and a well-defined, systematic method for addressing the most important drivers of materials cost together with key suppliers. The methodology is introduced by performing pilot projects, then anchored in the enterprise through organizational and procedural changes.
Using Student Preferences to Guide Design Team Composition
Authors: Wilde Douglass J. 
Published: February 2021

Abstract
For five years now Stanford’s Mechanical Engineering Design Division has experimented with restrictions on how students choose the members of their design teams. The constraints are based on voluntary student responses to a short questionnaire, essentially a sampling of questions from the Myers-Briggs Type Indicator widely used for vocational and educational counseling. This has produced teams performing qualitatively and quantitatively better, as measured by prizes won in the nationwide Lincoln Foundation Design Competition, than did teams of the thirteen years preceding. In 1995, Stanford teams won all but two of the twelve prizes awarded. This article describes these experiments, lists the results, describes how to construct a suitable questionnaire, reviews pertinent psychological theory, and gives mathematically precise instructions for constraining construction of the teams. The current procedure also incorporates information obtained from a recent survey on team satisfaction in a different project design course. This modified method seeks to generate satisfied teams without sacrificing prize-winning ability.
To Injection Mold, to Stamp, or to Assemble? Part I — A DFM Cost Perspective
Authors: Hu Weiyi , Poli Corrado 
Published: February 2021

Abstract
This paper presents a DFM cost comparison of injection molding and stamping, the processes most commonly used in the production of consumer oriented special purpose components. The general guidelines obtained and conclusions drawn in order to determine if a component should be injection molded or stamped, and/or if several components should be combined into a single component or not, are discussed. The cost evaluation and comparison are primarily in terms of the functional equivalence of feature, component, and assembly.
To Injection Mold, to Stamp, or to Assemble? Part II — A Time-to-Market Perspective
Authors: Hu Weiyi , Poli Corrado 
Published: February 2021

Abstract
This paper presents a time-to-market comparison of injection molding and stamping based on a comparison of overall production time periods. The general guidelines obtained and conclusions drawn in order to determine if a component should be injection molded or stamped, and/or if several components in an assembly should be combined into a single part or not, are discussed. The time evaluation and comparison are primarily in terms of the functional equivalence of feature, component, and assembly.
Performance Comparison Between Vibration Control by Confinement and Conventional Control Techniques
Authors: Allaei Daryoush 
Published: February 2021

Abstract
This paper presents some of the key results obtained in an investigation comparing the performance of the Vibration Control by Confinement technique with conventional vibration control methods using isolators, absorbers, and layer damping in their passive and/or active form. All four vibration suppression methods are applied to a system comprised of an elastic component resting on an elastic beam-type supporting structure. The finite element method is employed to model the system and generate the numerical results presented in this article. The system is subjected to a single harmonic disturbance applied directly to the beam. Kinematics variables are determined at the component and its interface with the supporting structure. Based on the results obtained via the FEM model, it is shown that the Vibration Control by Confinement technique outperforms, by a significant performance level, the conventional suppression methods studied in this project. Furthermore, it is concluded that the Vibration Control by Confinement technique is an effective and viable approach that not only has better performance, but has fewer limitations than current techniques. Furthermore, additional ramifications of the Vibration Control by Confinement approach as they apply to active vibration control systems are discussed.
Impedance Characteristics of Structural-Acoustic Control for Interior Noise Suppression
Authors: Jayachandran V. , Sun J. Q. 
Published: February 2021

Abstract
There has been a growing interest in interior noise control problems for aircraft and automobiles in recent years. While active noise cancellation (ANC) and active structural acoustic control (ASAC) are two main stream technologies, much attention has also been paid to sound absorption by active or semi-active means. Sound absorption occurs when the impedance of an absorbing medium such as an active foam or trim panel matches the impedance of the acoustic medium. To develop such an active or semi-active system for sound absorption, one needs to be able to describe the acoustic impedance accurately at the structural-acoustic interface. This paper presents a particular solution approach for solving the inhomogeneous Helmholtz equation, which allows us to obtain an accurate representation of the impedance field near the boundary. Qualitative and quantitative analysis of the impedance of the acoustic medium before and after active noise control are presented along with numerical results. The study in this paper provides a better understanding of the physics of the problem and may be useful in designing absorption systems for interior noise suppression.