bluuebunny/crossref_metadata_2025_split huggingface dataset:
Process Improvement Using Design by Experiments
Authors: Li Hsien-chen , Lin Fuyau 
Published: March 2021

Abstract
This paper present an approach to apply Design by Experiments for process improvement with the objectives to minimize cost and shorten investigation time. A case study of PCB (Printed Circuit Board) manufacturing process is chosen to illustrate this approach. A Fractional Factorial Design by Experiment was performed due to the constraints of the time, budget, and resources.
A Self-Organizing Fuzzy Controller Using Neural Networks
Authors: Li Wei , Wu Zuowei 
Published: March 2021

Abstract
This paper presents a self-organizing fuzzy logic control scheme based on neural networks, which consists of a traditional fuzzy logic (FL) controller and a conventional derivative (D) controller. Since membership functions regarding change-in-error ė represent the feedback of velocity they strongly affect transient behaviors of a system. In the proposed scheme, therefore, such membership functions are parameterized by the use of the cubic splines. Then, neural networks are adopted to optimize them in self-organizing process. To demonstrate the effectiveness of the proposed method, we report a number of simulation results involving both step and tracking control of a nonlinear plant.
Sensor-Based Robot Navigation in Uncertain Environments Using Fuzzy Logic
Authors: Li Wei , He Kezhong 
Published: March 2021

Abstract
This paper presents a new method for sensor-based mobile robot navigation in unknown environments using fuzzy logic. The inputs to the fuzzy control scheme consist of a heading angle between the robot and a specified target and distances between the robot and obstacles to the left, front, and right locations. The outputs from the control scheme are commands for the speed control unit of two rear wheels of a mobile robot.
Distances between the robot and obstacles are acquired by an array of ultrasonic sensors. Current coordinates of the robot are measured by a wheel ancoder system. The velocities of the driving wheels are controlled by a motor drive unit.
The main idea of the proposed method is quantitatively to formulate reactive behaviors and efficiently to coordinate their conflicts and competitions by fuzzy sets and fuzzy rules.
Simulation results show that the proposed method can be efficiently applied to robot navigation in complex and uncertain environments based on sensors.
Computer Simulations for Design and Optimization of a Fuzzy Control System
Authors: Edwards Dean B. , Canning John R. , de Sam Lazaro Anthony 
Published: March 2021

Abstract
The use of fuzzy logic in control systems is becoming increasingly popular as a method of handling non-linear control problems. The design of fuzzy systems is generally undertaken using intuition and a trial-and-error approach for tuning. A system so developed may be less than optimum as no accepted evaluation norms are available. In this paper a generic method to design and to optimize a fuzzy control system is developed. The results of computer simulations of a system constructed using this technique are submitted and discussed. The experimental verification of the method is presented.
Effective Integration of Computer Programming in Engineering Education
Authors: Untener Joseph A. 
Published: March 2021

Abstract
Computer programming assignments in technical courses often involve the instructor choosing a given problem from the text and requiring the students to write a program to solve that problem. While this approach provides the student with an opportunity to improve some skills, there may be more effective approaches.
This paper discusses an approach that initially gives the student only a narrative describing a company’s set of circumstances. The class then discusses how the situation might be improved using computer applications. Through discussion, a set of parameters for the application is developed. By the end of the discussion, the application that will help the company has been defined by the students. The required features and the desirable features are identified. The outcome of the discussion becomes the computer assignment.
When used in a fluid mechanics course by the author, the approach yielded many benefits. The students a) had personal ownership in the assignment, b) were able to see the true power of the computer in automating a repetitive process, c) developed logic and critical thinking abilities, and d) solved a problem similar to ones they will face upon graduation.
Optimal Tolerancing: The Link Between Design and Manufacturing Productivity
Authors: Iannuzzi Mark , Sandgren Eric 
Published: March 2021

Abstract
A computational design tool is presented which permits the optimal allocation of tolerances for mechanical and electrical components and assemblies. The basic approach involves the coupling of a nontraditional optimization method with a Monte Carlo based tolerance analysis. The objective is to determine the tolerance range value to assign to each nominal dimension which minimizes the production cost of the component or assembly while simultaneously meeting all critical dimensional and functional constraints imposed upon the design. A discretization of possible tolerance range values is performed and a global search is conducted by a genetic algorithm. Both the fine and course grain performance of the combined algorithm is demonstrated on a series of test problems ranging from a simple assembly of blocks to several real mechanical design problems. Solutions generated on problems taken from the literature indicate superior performance to existing techniques. Extensions which would allow for a complete optimal dimensional management environment are examined.
Including Imprecision in Engineering Design Calculations
Authors: Law William S. , Antonsson Erik K. 
Published: March 2021

Abstract
The Imprecise Design Tool (IDT) presented in this paper is a working computer implementation of the method of imprecision, a formal theory that represents preferences among design alternatives. An aircraft engine design example indicates how the IDT may be applied to support engineering design decisions, using the Engine Development Cost Estimator provided by General Electric Aircraft Engines, Cincinnati, Ohio.
The Roles of Features and Abstraction in Mechanical Design
Authors: Taylor LeRoy E. , Henderson Mark R. 
Published: March 2021

Abstract
This paper describes the roles of features and abstraction mechanisms in the mechanical design process, mechanical designs, and product models of mechanical designs. It also describes the relationship between functions and features in mechanical design. It is our experience that many research efforts exist in the areas of design and product modeling and, further, that these efforts must be cataloged and compared. To this end, this paper culminates with the presentation of a multi-dimensional abstraction space which provides a unique framework for (a) comparing mechanical engineering design research efforts, (b) relating conceptual objects used in the life cycle of mechanical products, and (c) defining a product modeling space.
Testing Design Methodology Through Task Performance
Authors: Rückert Carsten , Springer Johannes 
Published: March 2021

Abstract
While design methodology is well accepted at universities, it is rarely used for industrial design work. This rift is caused by widespread skepticism regarding methodology in the industry. At the Technical University of Berlin, 13 mechanical engineers performed a design task in a laboratory experiment. The study has provided some results that can help to dissipate criticism of methodology. Furthermore, specifications for improving methods have been derived.
Analyzing Inter and Intra Group Information Exchanges in Conceptual Collaborative Design
Authors: Waldron Manjula B. , Brooks Regina L. 
Published: March 2021

Abstract
This paper reports preliminary results from a technique used to study inter and intra group information exchanges which occur in the conceptual stages of collaborative group design. In the early stages of conceptual design, there is little information to guide the designers and they find themselves groping to find pertinent information which may help them. In collaborative group design the members are able to pool in both their knowledge as well as knowlwdge from other groups. Currently there are no techniques, which exist, to help track this group information exchange. In this paper, we use the sense-making theory to guide us in assessing the information needs of the designers engaged in group collaborative design. In this study, the sense-making theory is described and adapted for applications in the engineering design domain. The analysis technique is a two step process. First the records are transcribed and labeled and then interpreted. The technique allows one to obtain a chronological map of the information seeking, helps obtained, and the decisions made. Results from the first design session show that during the early phases of group design, the most needs arose in establishing the knowledge base and in identifying the design process. There was a strong need for inter and intra group information exchange.
Critical Thinking: Evolution of a Freshman Graphics Course
Authors: Sanchez Lilia A. , Hight Timothy K. , Gainen Joanne 
Published: March 2021

Abstract
We have redefined the goals of the Freshman course in Engineering Graphics at Santa Clara University to emphasize graphic communication skills as a vehicle to introduce the design process and a design experience. Integration of the critical thinking component into the course has led to our own iterative, interactive design process of a more effective teaching methodology.
Determination of the Interference Distance Between Two Objects Using Optimization Techniques
Authors: Nahon Meyer 
Published: March 2021

Abstract
The determination of the interference distance between objects is a problem encountered in the off-line simulation of robotic systems. It is similar to the problem of finding the minimum separation distance between two bodies — a problem which, at present, is commonly solved using optimization techniques. This paper presents an analogous optimization formulation for the quick and accurate determination of the interference distance between two interfering objects. The optimization problem consists of finding the maximum amount by which the boundaries of two interfering object can be moved back while still maintaining a non-empty interference volume. Since the approach used is similar to that used in the minimum separation problem, a single algorithm has been implemented which, given the position and orientation of two objects, will return the separation or interference distance between the objects, as appropriate.
Path Planning for Spheres in Three Dimensional Environments With Low Interference Index
Authors: Storti Duane W. , Dutta Debasish 
Published: March 2021

Abstract
We consider the path planning problem for a spherical object moving through a three-dimensional environment composed of spherical obstacles. Given a starting point and a terminal or target point, we wish to determine a collision free path from start to target for the moving sphere. We define an interference index to count the number of configuration space obstacles whose surfaces interfere simultaneously. In this paper, we present algorithms for navigating the sphere when the interference index is ≤ 2. While a global calculation is necessary to characterize the environment as a whole, only local knowledge is needed for path construction.
An Octree Method for Interference Detection in Computer Aided 3-D Packing
Authors: Dai Zuo , Cha Jianzhong 
Published: March 2021

Abstract
In simulating the three dimensional packing process with arbitrary shaped objects, the task of detecting interference between objects is important and very difficult. This paper, representing the three dimensional packing space and objects with an octree, presents an effective interference detection algorithm, which can overcome the performance shortcomings that the conventional methods have in terms of real-time response, computer memory and computational accuracy. By recording the distribution status of packing space in the “bits” of short integers, the data space can be compressed to 1/16 of that used by conventional algorithms.
Robust Concurrent Concept Selection and System Synthesis
Authors: Chen Wei , Allen Janet K. , Mistree Farrokh 
Published: March 2021

Abstract
In this paper, we introduce a concurrent approach to preliminary system design by using a modification of Taguchi’s method of robust design. It is possible to model interactions among component concept selections and synthesis of system variables. This approach also can improve computational efficiency and provide more design knowledge for the conceptual design of complex engineering systems. This technique is effective in dealing with both discrete and continuous variables simultaneously in design. We illustrate our approach by the preliminary design of a solar powered irrigation system. The selections of critical component concepts are integrated with the determination of system variables, i.e., the thermodynamic operating parameters.
Concurrent Designing of Airframes: State of the Art and Trends
Authors: Petiau Christian 
Published: March 2021

Abstract
We will first recall that the organization of airframe designing stands in direct relation to the performance capabilities of available tools, which is, in fact, what determines the number and the nature of project iterations.
We then present and analyze an organization type which can nowadays be recommended in view of the currently available CAD, computation and mathematical optimization means.
This leads to a first design which is followed by experimental verification, with a key role for flight tests. The final design is checked with the aid of computation models that have been calibrated with the results of the performed tests.
We will then examine new tools, since they are factors in the future evolution of the design methodology, including:
• availability of the “design history”, as a set of all data of the whole process,
• structure optimization with parametric CAD and multidisciplinary optimization
• “feature” modeling
• enhancement of the computation methods
As a conclusion, we show that significant gains in terms of productivity and quality can be expected from these new products, both at design and at production level. What remains, however, to be found, are the most appropriate concurrent engineering organizations that are best suited to these new tools.
Monotonicity and Goal Interaction Diagrams for the Compromise Decision Support Problem
Authors: Smith Warren F. , Mistree Farrokh 
Published: March 2021

Abstract
Our approach in this paper is an introspective one with respect to modeling. Rather than examining what can be done with a model and how it can be built up or synthesized, we focus on the mathematical characteristics and how a model might be broken down or analyzed. Firstly, using monotonicity principles, this culminates in the identification of the nonlinear constraint and goal functionality and variable monotonicity, and secondly, in the development of the Goal Interaction Diagram. As various scenarios are examined, this information leads to improved efficiency and effectiveness within the design process through enhanced understanding. The case study we use to illustrate our approach deals with a real world example, namely, the preliminary design of a naval frigate. A working knowledge of naval architecture, however, is not required to understand the concepts being discussed.
Parametric Volume Models for Interactive Three-Dimensional Grid Generation
Authors: Mokhtar Jawad D. , Oliver James H. 
Published: March 2021

Abstract
A method based on non-uniform rational B-spline (NURBS) curve, surface, and solid technology is presented for interactive grid generation of three-dimensional flow fields encountered in turbomachinery applications. The method allows construction of several types of multi-block grids including H-, O-, and C-grids for two-dimensional grids, and strict H-grids for three-dimensional grid generation. Automated two-dimensional block construction is facilitated via a traversal method that searches four-sided regions in the initial block structure. A NURBS surface is then constructed on each block by transfinite interpolation of the boundary curves themselves, and various point distribution options may be applied. Three-dimensional grid generation is an extension of the two-dimensional procedure. Tri-parametric hyperpatches (NURBS solids) are constructed from the two-dimensional block surfaces and grids may be generated via several point distribution functions. This method exploits existing geometric design data via Initial Graphics Exchange Specification (IGES) input of NURBS-based component geometry. It provides an efficient and robust method for complex grid generation to support a variety of analysis functions. Several example applications are presented to demonstrate the capabilities of the technique.
Impact Analysis of Plates Using Quasi-Static Approach
Authors: Shivaswamy Shashishekar , Li Jianmin , Lankarani Hamid M. 
Published: March 2021

Abstract
Impact calculations suffer from several practical limitations which limit their application to establishing the approximate magnitude of the various phenomena involved. The transient force deformation response of a body subjected to impact can be explained accurately using stress wave propagation theory. As this approach is very complicated, a simpler quasi-static approach with non-linear force deformation Hertz relations can be employed for impact analysis. However, these relations can not explain the energy absorption and permanent deformations encountered during the impact. This necessitates independent non-linear force-deformation relations for compression and restitution phases of impact.
In the present paper, impact tests conducted on Aluminum and Steel plates have been reported. The impact response of the system was compared with the various theoretical quasi-static force models. Considering the assumptions made in the quasi-static force models, the experimental results matched very well with the theoretical results. Non-linear force-deformation model with independent relations for compression and restitution phases was found to be the best approach to analyze impact problems. The value of the index in the non-linear force-deformation relations was found to be approximately 1.71 and 1.78 for Aluminum and Steel respectively. The values of impact parameters for a given material were found to depend on impact velocity.
Evaluation of Factors Affecting the Simulation of Structural Vibrations in Rolling Bearings
Authors: Mehra Kapil , Datta Jayanta , Farhang Kambiz 
Published: March 2021

Abstract
An analytical model is developed for studying in-plane structural vibrations in rolling element bearings. A lumped parameter approach is employed in developing the model. The mass and moment of inertia of the components comprising the bearing are lumped at their respective centers of mass. The localized stiffnesses due to contact deformation phenomenon are treated as nonlinear springs. The variable spring rates are obtained by application of Hertz equation for elastic contact deformation.
Effects of preload, ball rotational speed, and damping are studied using the formulation. An interesting observation is made as to the influence of preload. It is found that in the presence of preload, irrespective of the load magnitude, contact is maintained with both the inner and the outer races. Hence, responses obtained with and without the check for ball/inner race and ball/outer race interferences are identical. In addition, no appreciable change is observed in the responses when the preload value is varied from 10 N to 1N. At high speed of operation, the balls are found to maintain contact with the outer ring, whereas intermittent contact with the inner ring occurs for brief periods of time. Introduction of lubricant is found to dampen the oscillations considerably.
A Simplified Model for Structural Vibrations in Ball Bearings
Authors: Farhang Kambiz , Mehra Kapil , Datta Jayanta 
Published: March 2021

Abstract
More often than not, in studies involving dynamics and vibration of rotor systems, the bearings within a rotor system are treated as linear components. However, it is well understood that bearing systems are nonlinear due to both their geometrical properties and Hertzian contact between their components. This paper develops a linear formulation to approximate the vibration behavior of rolling bearings. A study of the approximation in the linear representation for rolling bearings is presented in which the effects of preload, lubricant viscosity and outer ring mass on the accuracy of the linear representation are determined.
The equations of motion governing the vibrations of rolling element bearing are found to be a set of second-order, nonlinear ordinary differential equations with position periodic coefficients. These equations are linearized about nominal values of the position vectors of the rolling element and the outer ring center. The linearized equations of motion are solved to obtain the small perturbations (displacements) from the nominal positions.
The results show that the linear model representation is applicable for bearings with preload. Existence of damping and/or greater outer ring mass enhance the approximation provided by the linear model. Most importantly, the linear representation provides a conservative estimate of the rolling element motion and very accurate estimate of the outer ring motion.
Structural Shape Optimization Wth Error Control
Authors: Duysinx Pierre , Zhang WeiHong , Zhong HaiGuang , Beckers Pierre , Fleury Claude 
Published: March 2021

Abstract
A robust and automatic shape optimization procedure is presented in this paper, which incorporates recent developments in the field of computer-aided design (CAD) of mechanical structures, such as geometric modelling, automatic selection of independent design variables, sensitivity analysis using reliable mesh perturbation schemes, error estimation and adaptive mesh refinement. A numerical example is given to show the efficiency of the procedure.
Generation of Conceptual Design for Structural Shapes and Functional Elements of Machine Systems Having no Preconceptions Concerning the Design
Authors: Yoshimura Masataka , Nose Kohji 
Published: March 2021

Abstract
This paper presents a methodology for generating conceptual designs of structural shapes and functional elements of machine systems from initial conditions having no preconceived information. Firstly, a feasible design region initially containing nothing is defined. The whole feasible region which is uniformly filled up with finite elements having an extremely low rigidity is here assumed to be a region containing nothing. Then, a seed element grows into a whole structural system in the feasible design region by conducting both the creation of external shapes and the growth of the inner structures. Next, the design method is advanced so that a functional element of a rotational joint is also generated with the structural shapes simultaneously. Finally, the proposed conceptual design method is applied to design of industrial robots.