bluuebunny/crossref_metadata_2025 huggingface dataset:
A Feature-Based Approach for Representing Composite Components
Authors: Xu X. William
Published: June 2008

The progress with which composite materials are being used in industry has been staggering. The methods, processes and procedures of developing and manufacturing composite materials have always been the center stage for the composite materials research and applications. While feature technologies, in particular feature-based design, have been widely practiced by many in the areas of designing and manufacturing conventional materials, one has not yet seen it help to reap the benefits for composite materials manufacturing. This paper proposed a feature-based approach for representing composite components. Two types of features have been defined, structural and geometrical. Based on the suggested approach toward representing features on a composite component, a concurrent engineering kernel is being developed, in which design and manufacturing of composite manufacturing come together seamlessly to enable a complete product development environment for composite material design and manufacturing.
Quality Function Deployment for Environment (QFDE) to Support Design for Environment (DFE)
Authors: Masui Keijiro , Sakao Tomohiko , Aizawa Seiichi , Inaba Atsushi
Published: June 2008

This paper presents a methodology for applying Quality Function Deployment (QFD) to environmentally conscious design in the early stages of product development. The benefit of this approach is the simultaneous consideration of conventional design factors and environmental aspects during conceptual design. QFD’s main mission is to translate customer requirements to product characteristics and design attributes. QFD clarifies what is important for a product to be competitive in the market and identifies engineering specifications and designs that respond to the “voice of customer (VOC).” QFD for the Environment (QFDE) we propose could be applied to environmentally conscious design by including environmental aspects as quality requirements in addition to conventional VOCs. After discussing what kind of requirements and attributes of a product should be considered from the environmental point of view, we came up with a set of environmental quality requirements and engineering specifications, and their correlation factors. Design engineers can find out which parts are the most important parts to enhance environmental consciousness of their products by executing QFDE phase I through phase II. Further, we developed a methodology to evaluate the effects of design improvement concerning the parts on environmental quality requirements as phase III and IV.
Setup Level Tool Sequence Selection for 2.5-D Pocket Machining
Authors: D’Souza Roshan M. , Se´quin Carlo , Wright Paul
Published: June 2008

This paper describes algorithms for efficiently machining an entire setup. A setup consists of a set of features with precedence constraints, that are machined when the stock is clamped in a particular orientation. This work extends earlier research which addressed the issue of selecting an cheapest tool sequence for a single pocket.
Dimension Set Recognition Methodologies
Authors: Xu Xun W. , Wu Yuequan
Published: June 2008

Recognition of dimension sets plays an important role in computerizing paper-based engineering drawings. The dimensioning mechanism and its geometric properties have been extensively studied in the past, based on which various techniques have been developed in respect to dimension text and graphics separation, and dimension graphics recognition. This paper reviews the methodologies of automatically recognizing dimension sets in an engineering drawing. Related computerization processes are backgrounded. The elements and classification of a dimension set are described by means of its syntax and semantics. The algorithms for dimension text extraction, dimension graphics recognition and text-graphics aggregation are presented in detail. Some unsolved issues are also addressed. The review is focused on recent research results in the pertinent areas.
Milling Cutter Selection for 3D Models Acquired by Scanning
Authors: Yao Zhiyang , Gupta Satyandra K. , Fowler Gregory
Published: June 2008

In this paper, we describe: 1) an algorithm that generalizes the exiting cutter selection approach to solve the problem of finding an appropriate sequence of cutters for a 3D model produced using 3D scanning, and 2) algorithms for finding the coverable area both exactly and approximately for 3D surfaces represented using a set of triangular facets. The algorithms described in this paper have the potential to reduce the time spent on manual planning, and to reduce the total machining time by generating improved process plans.
A Reconfigurable 3D Engineering Shape Search System: Part I — Shape Representation
Authors: Iyer Natraj , Kalyanaraman Yagnanarayanan , Lou Kuiyang , Jayanti Subramaniam , Ramani Karthik
Published: June 2008

This paper presents an approach for a reconfigurable shape search system for 3D engineering models using a client-serverdatabase architecture. The current paper focuses on the server functionality, while a subsequent paper will focus on the database issues. The server takes the shape query as input from the client and converts it into feature vectors and a new skeletal graph representation which we have developed. The algorithms such as voxelization, skeletonization, and skeletal graph extraction for accomplishing these are described in detail. The principal advantages of the skeletal graph representation are that (i) it preserves the geometry and topology of the query model, (ii) it is considerably smaller than the B-Rep graph, and (iii) it is insensitive to minor perturbations in shape, while sensitive enough to capture the major features of a shape. Our representation is also synergistic with the human cognitive representation of shape. The results indicate that the skeletal graph is considerably smaller than the B-Rep graph even for complicated shapes.
RLSM: Remote Excimer Laser Micro-Machining Services Model
Authors: Uppuluri Sreemanth M. , Xu Xianfan , Ramani Karthik
Published: June 2008

In this paper, we discuss an Internet based excimer-laser-micro-machining services model that allows multiple users to collaboratively design and fabricate laser micromachining features. This model implements the client-server architecture to support design and editing of features by multiple clients. The client side needs minimum software installation and is made intelligent by incorporating feature verification algorithms to ensure speed and efficiency of the design process. The server side supports solid modeling, solving of geometric constraints, data management and synchronization of clients. JSDT Interface links the server and the client sides. The remote laser micro-machining services model (RLSM) provides a collection of laser micro-machining features such as through-cuts, channels and pockets and different polymer materials such as PMMA, Kapton®, PET and Uplex® for the user to choose from. These design variables from the user are mapped to the corresponding technological parameters for laser micro-machining. The manufacturing feasibility is then assessed with respect to the system capabilities by implementing intelligent algorithms on the client side. In developing this services model we provide a distributed collaborative architecture that incorporates the manufacturing constraints of laser micro-machining in the design stage. The remote service center operation is further integrated with automated path generation for laser micromachining of the features. To our knowledge this is the first attempt towards developing a collaborative environment for design and manufacturing of MEMS components. The importance of such a model in the manufacturing arena is also discussed.
Mobile Representation of Complex Assembly Processes in Automotive Industry
Authors: Matysczok Carsten , Parisi Salvatore , Ebbesmeyer Peter , Krumm Holger
Published: June 2008

Today in aircraft and automotive industry highly complex products are manufactured. For the assembly of those complex products specialized and long trained employees are necessary to guarantee a consitent high quality of products. To reduce the training time and to allow even untrained employees the assembly of e.g. a car engine a dedicated concept has been developed to provide the emplyees with the necessary information. This paper describes the concept and the realization of a method for the representation of simulation data of complex assembly sequences on mobile devices (PDAs, wearables, etc.). Therefore the mobile device identifies the components to be assembled. It shows the correspronding assembly simulation on the display and receives feedback of the assembly operator. This feedback can be freely spoken into the device (e.g. comments on the simulation, misfits of assembly parts, demands for a better quality of the simulation, more detailed representation of single assembly steps) and is automatically sent by email to the person in charge. The modified simulation (according to the feedback of the assembly worker) is then transferred back to the PDA during the synchronization at the docking station.
Generation of Process Plans for Laser Chemical Vapor Deposition
Authors: Park Jae-hyoung , Rosen David W.
Published: June 2008

Rapid Prototyping (RP) technology refers to the fabrication of an arbitrary three-dimensional part layer-by-layer. Laser Chemical Vapor Deposition (LCVD) is a promising RP and manufacturing process that deposits metals and ceramics by local heating of a substrate with a laser. Even though many LCVD process planning characteristics are shared with those of more common RP technologies, LCVD process planning requires new efforts due to its unique characteristics. Unlike a conventional RP technology that only builds horizontal planar layers, LCVD can build conformal layers (conform to nonplanar substrates), thin walls, and fibers (rod-shape) as build primitives. Based on these unique characteristics, we have developed the overall approach for LCVD process planning and developed several of the main methods in this approach. In this paper, we report on the overall approach, the conformal slicing algorithm, and two different 1D path generation algorithms. Two examples are presented to illustrate the application of the process planning methods.
Lessons From Experimental Computer Assisted Sketching Tool for Planar Mechanisms
Authors: Pardasani A. , Dickinson J. , Li Z. , Zeng Y. , Antunes H.
Published: June 2008

This paper describes the authors’ experiences in implementing a prototype to explore the technical and research challenges in developing a mechanical design system based on the sketching metaphor. This includes basic approaches, methodology, framework, and research issues. Since the objective of the developing the prototype was to identify the issues, a simple, yet representative design domain of conceptual design of planar mechanisms was chosen. The prototype has the functionality to support users creating skeleton sketches of planar mechanisms on a tablet PC. The freehand sketches are then interpreted to derive the structure of the mechanism consisting of linkages and joints. The paper describes the approach for deriving components from skeleton diagrams and outlines the research challenges in way of creating design tools based on the sketching metaphor.
Synthesis of Geometric Tolerances of a Gearbox Using a Deviation-Based Tolerance Synthesis Scheme
Authors: Pramanik N. , Roy U. , Sudarsan R. , Sriram R. D. , Lyons K. W.
Published: June 2008

In this paper a step-by-step procedure for carrying out synthesis of geometric tolerances of a planetary gearbox using a deviation-based tolerance synthesis (TS) scheme has been presented. The TS scheme uses an optimization for minimizing total cost of manufacturing, subject to constraints for assemblability of parts and constraints for functional requirements. The TS work is carried out in several stages. First the gearbox with its nominal dimensions is converted into a model that could serve as input to the synthesis module. Cost functions and constraints equations are then generated using deviation parameters of features. The optimization is carried out using these equations in standard non-linear minimization tools (Matlab) and the optimal deviation parameters are subsequently mapped into suitable tolerance specifications or tolerance zones as per ANSI Y14.5 tolerancing standards.
Boundary Evaluation for a Cellular Model
Authors: Bidarra Rafael , Neels Willem J. , Bronsvoort Willem F.
Published: June 2008

Feature modeling systems usually employ a boundary representation (b-rep) to store the shape information on a product. It has, however, been shown that a b-rep has a number of shortcomings, and that a cellular model can be a valuable alternative. A cellular model stores additional shape information on a feature, including the faces that are not on the boundary of the product. Such information can be profitably used for several purposes. A major operation in each feature modeling system is boundary evaluation, which computes the geometric model of a product, i.e. either the b-rep or the cellular model, from the features that have been specified by the user. Because it has to be executed each time a feature has been added, removed or modified, its efficiency is very important. In this paper, boundary evaluation for a cellular model is described. Subsequently, its efficiency is compared to the efficiency of boundary evaluation for a b-rep, on the basis of performance measurements and considerations for both. It turns out that boundary evaluation for a cellular model is in fact more efficient than for a b-rep, which makes cellular models even more attractive as an alternative for b-reps.
An Effective Use of CFD Analyses and Model Testing With a Computerized Data Acquisition System
Authors: Batchelder Jason H. , Khosrowjerdi M. , Presz Walter M.
Published: June 2008

Mixer/ejector exhaust systems provide a unique means to reduce the jet noise associated with older aircraft while providing little or no impact on aircraft performance. This paper presents the results of using CFD analyses and ejector model testing to minimize installation losses associated with such mixer/ejector noise suppressors. Ejector performance data is obtained using dual flow model tests combined with a computerized data acquisition system. The resulting data is used to generate ejector performance results to calibrate an existing CFD analysis for ejector application. The calibrated CFD analysis is used to both analyze and modify existing pylon contouring to significantly reduce cruise losses associated with the ALMEC noise suppressor installation on the Gulfstream GIIB aircraft.
Extracting Geometrical Data From CAD STEP Files
Authors: Pan Chunxia , Smith Shana
Published: June 2008

Most CAD tools currently do not have advanced capability built in for directly analyzing the feasibility of product assembly during the design stage. As a result, the feasibility of product assembly has to be analyzed using external assembly analysis tools. To integrate external assembly analysis tools with CAD tools, geometrical data from the CAD models must be extracted from CAD files and imported into the assembly analysis tools. To transfer geometrical data between CAD tools and assembly analysis tools, a neutral file format is needed. STEP (standard for the exchange of product model data) is a neutral file format for convenient and reliable data exchange between different design and manufacturing systems. Therefore, STEP is considered as one of the most popular formats for saving designs. As a result, to evaluate designs, extracting geometrical data from CAD-STEP file is important. Comparing with some other currently available methods, first translating STEP file into XML and then using Java DOM to get geometrical information from XML file is much better. This paper explores the process of extracting geometrical data from a CAD-STEP file for assembly sequence planning. A STEPXML translator, Java-XML parser and DTD (document type definition) generator are used on the JDK 1.4 platform. In this project, DOM (document object model) is applied as the API (Application Programming Interface) for XML.
Data Model Support to Assist the Concurrent Design of Injection Plastic Parts and Their Moulds
Authors: Morano He´ctor , Borja Vicente , Lo´pez Marcelo , Ayala A´lvaro
Published: June 2008

Product models come from the analysis of data requirements to support product design and manufacture. These models are implemented in databases aimed at providing information to software applications that assist the concurrent design of products. This paper presents the specifications of data models to assist the concurrent design of injection plastic parts and their moulds. The product models are original since they capture part and mould life cycle aspects using the same data structure. The models also link product functional information to the design process and consider the capacities of an injection machine. The paper introduces the underlined structure of the above mentioned data models and uses a case study to show their capabilities. Finally, some conclusions are presented.
The Design Exemplar: The Foundation for a CAD Query Language
Authors: Divekar Ameya , Summers Joshua D.
Published: June 2008

Design engineers create models of design artifacts with commercial Computer Aided Design (CAD) solid modeling systems and manage the data files through Product Data Management (PDM) systems. These systems stop short of providing support for querying and retrieving data from “within” the CAD data files. A true CAD query language that allows designers the flexibility to describe queries against single and multiple CAD files would be of great benefit for design engineers. This query language ought to be both datacentric and user-centric in nature. The design exemplar, a datastructure that provides a standard representation of design knowledge based upon a general constraint validation and satisfaction algorithm, is shown here to be a concept upon which a CAD query language may be developed. The first required extension of the design exemplar is the inclusion of logical connectives. Some insights into the different levels at which the extensions may be implemented are discussed. Also, some applications retrieving geometric data using this query language are demonstrated. The query language, as it evolves, is expected to support geometric retrieval across domains and offer an all-purpose approach to geometric retrieval.
A Model Repository for Automotive Embedded Control Systems Design
Authors: Butts Kenneth R. , Rangan Ravi , Jennings Mark , Cheng Gail
Published: June 2008

Model-based product development methodologies are becoming more widely used by developers of automotive embedded control systems. This paper presents a model repository intended to provide configuration management, reuse, and sharing infrastructure in support of this trend. An initial set of repository requirements is presented and then augmented with lessons-learned from a pilot realization of the system. This pilot realization is discussed with respect to implementation and application. A repository data model is also described.
Multi-Dimensional Heat Transfer and Fluid Dynamics Analysis of a Lawnmower Tractor Exhaust System
Authors: Reza Md Shamim , Hagen P. A. , Amano R. S.
Published: June 2008

The objective of this study was to investigate the present cooling system of a lawn mower tractor engine and come out with an idea to modify the system. The test section was created to measure the velocity and temperature around the engine compartment. Velocity and temperature measurements were collected at several different locations around the engine. To accomplish this, several Pressure transducers along with Pitot tubes and Thermocouples were placed at several predetermined locations based on their assumed experimental importance. Since the experiment was run in a laboratory setting, the Combustion products of the engine were vented to the environment through a venting system via a stainless steel hose. This hose was constructed to attach to both the tractor muffler and the building venting. Then, the instrumentation had to be sized and selected such that the data could be easily acquired and recorded. Next, the necessary data was collected using the selected instrumentation while running the engine in the laboratory space. This data was used to produce an accurate computer model for simulation and to compare several different design adaptations. Based on experimental and computational data, it is noticed that the engine compartment was exhausting hot air that was causing discomfort to the operator and potential harm to the area near their feet. Some modifications were recommended, such as the baffling system, fan system, and grill alterations as an attempt to alter the airflow characteristics of the engine compartment to redirect the hot air away from operator’s feet.
A Numerical Investigation on the Mixing Behavior of Microcombustors
Authors: Anchondo Ivan A. , Choudhuri Ahsan R.
Published: June 2008

This paper presents a numerical investigation of the mixing of methane and air inside a 5mm high and 40 mm long 2-D channel type microcombustor. Two fuel-air injection schemes are studied at different equivalence ratios. Configuration-I injects methane from an axially located port, whereas configuration-II injects methane from two radially located opposing ports. The velocity field and local methane mixture fractions indicate that the configuration-I provides a superior mixing for lean, stoichiometric and rich equivalence ratios. However, configuration-II yields sufficient mixing only at a fuel rich condition. Also, despite geometrical symmetry of the chamber, flow-fields are highly asymmetric at a lean condition in both configurations.
Swirl and Combustion Effects on Flow Dynamics in Lean Direct Injection Gas Turbine Combustion
Authors: Archer S. , Gupta A. K.
Published: June 2008

The effect of swirl and combustion are presented for a Lean Direct Injection (LDI) configuration in gas turbine combustion. Specifically, the effect of radial distribution of combustion air and swirl in a burner are examined under nonburning and burning conditions using propane as the fuel. The present study explores single swirler interaction with the use of an experimental double concentric swirl burner that simulates one swirler of a practical gas turbine combustor. Flowfield data has been obtained using Particle Image Velocimetry (PIV) for varying swirl distributions. The flow characteristics of the resulting flowfields have been examined under lean direct injection (LDI) conditions. The affects of coand counter-swirl have also been carried out. Results showed that both swirl and combustion has significant effect on the characteristics of the internal and external recirculation zones. Combustion provides greater axial velocities than their counter non-combustion conditions. The counter-swirl combination resulted in smaller and more well defined internal recirculation regions. The results provide the role of swirl and combustion on the mean and turbulence characteristics of flows over a range of swirl and shear conditions between the inner and outer flow of the burner. This data provides important insights on the flow dynamics in addition to providing data for model validation and model development.
Computer Aided Design of Indoor Air Quality and Airflow Distribution in Surgical Operating Theatres
Authors: Kameel Ramiz , Khalil Essam E.
Published: June 2008

This paper reviews the previous attempts to evaluate the Indoor Air Quality (IAQ), investigates previously proposed IAQ factors and analyses the evaluation methods of these factors. The present work introduces, also, a new hypothesis of the optimum HVAC airside system design of the surgical operating theatres to achieve the comfort and hygiene levels. The present work is devoted to propose and formulate a new scale capable of adequately evaluating the airflow pattern in the surgical operating theatres. The proposed new scale is proposed to cover the local and overall air quality evaluations. The present new hypothesis is developed to overcome the difficulties experienced using other IAQ evaluations for typical surgical operating theatres. This paper recommends some designs of the supply air outlets to provide the vertically downward airflow as a practical solution. The near ceiling and near floor extract ports are to be used instead of the hypothetical complete floor extract as a practical solution.
“Portalet” Platform for D.I.Y. E-Business Solutions for SME’s
Authors: Zhao J. B. , Huang George Q.
Published: June 2008

The potential benefit and cost of adopting EBS (Ebusiness Solutions) solutions are both high. They are major attraction and concern for Small and Medium sized Enterprises (SMEs) respectively. However, SMEs are generally unclear and have many difficulties in choosing or developing an appropriate EBS. This paper will address these issues by proposing a platform “DIY (Do It Yourself)” approach which integrates software product platform theories and EBS development practice. “Portalets” are proposed and developed as building blocks of this platform and their requirements, features and structures will be investigated. By mapping the functional requirements to the portalets platform, an EBS can be easily built by gluing the portalets which can be selected from the platform with customization.
A Web Platform for the Exchange and Transformation of Business Objects
Authors: Aldous Kenneth J. , Lintott Andrew B.
Published: June 2008

Internet technologies provide a means of implementing data exchange systems incrementally, from connecting two applications on the one machine to implementing an Internetwide information system. Recent advances in XML and related technologies greatly facilitate data extraction and reformatting, thus enabling data from one or more applications to be prepared for use by another. A model, based on these technologies, is described for the exchange of business documents among disparate computer applications used to manage manufacturing operations. The model comprises two parts, the first of which includes a set of code modules, written in Java, for handling requests to retrieve information from one or more Web resources, composing the retrieved data into an XML document and delivering the result. The second part comprises a set of what are termed XSL meta-stylesheets for transforming the retrieved documents into the various forms required by recipient computer applications. Meta-stylesheets are used to transform simple declarative XML documents into more complex stylesheets to add new material to received documents, invert the structure of XML documents and make changes to selected text within the documents.
Rapid Application Development of Process Capability: Supplier Models
Authors: Karthik S. , Chung C. W. , Ramani K.
Published: June 2008

Rapid changes and specialization in technology make it increasingly difficult for designers to keep track of the current capabilities of manufacturing processes and choose the appropriate one. Improper process selection leads to higher costs, lower quality and wrong choice of the supplier. Currently, there is no software advisory system to help the design/procurement personnel in process and supplier selection. The complexity involved in building an application encompassing the capabilities of dozens of processes and its associated suppliers acts as a deterrent for application service providers. This paper discusses a technique to rapidly develop web applications to identify a suitable manufacturing process and supplier/s using Rapid Application Development (RAD). RAD refers to a new computing paradigm to develop software applications within a short time frame. The technique has been verified by developing an advisory system to identify a suitable plastic process and supplier/s. The methodology is currently limited to common manufacturing methods such as castings, forgings, sheet metal and plastic/composite manufacturing. Benefits realized using RAD include shorter design and development times, code reusability and standardization.
A Framework for Internet Based Product Information Sharing and Visualization
Authors: Zhang Shusheng , Shen Weiming , Ghenniwa Hamada H.
Published: June 2008

Internet based product information sharing and visualization is the foundation for collaborative product design and manufacturing. This paper presents a Web based framework with a STEP based product data master model and VRML based visualization techniques for visualizing and sharing product information among designers, production engineers and managers, purchasing and marketing staff, suppliers, and customers. A prototype software environment is implemented to validate the proposed framework and related technologies.
Simulation of New Automobile Lighting Systems for a Nightdrive Application
Authors: Berssenbru¨gge Jan , Matysczok Carsten , Po¨hland Klaus , Weber Thomas , Ebbesmeyer Peter
Published: June 2008

For the development of new automobile lighting systems, special raytracing methods are needed to create physically correct simulations of the illumination properties. For further evaluation, test drives with physical prototypes are still necessary. But changing weather and lighting conditions make the test drive results not fully comparable. Therefore, a high number of test drives have to be performed. This leads to a costintensive and time-consuming development process. Virtual test drives at night combined with a realistic simulation of a lighting system’s illumination characteristics can minimize the number of real nightdrives and allow reproducible testing conditions as well as comparable results. A close-to-reality simulation poses high demands on real-time methods for calculating and displaying illumination data in a virtual scene. Furthermore, the geometry model of the scenery which is to be illuminated needs to be adapted to fulfill these demands. This paper introduces a real-time illumination method for use in a nightdrive simulation which illuminates scenery models using coarse polygon meshes.
A Prototype Web-Based Custom Product Specification System
Authors: Farrell Ronald S. , Stump Gary , Park Jaeil , Simpson Timothy W.
Published: June 2008

For companies who must provide customized products on demand, it is important that the voice of the customer be addressed and incorporated early into the design process. Web-based design interfaces have emerged as useful tools to make customer voices interactive and provide a customer-friendly and cost-effective interface. The effectiveness of the interface can be greatly enhanced through implementation of a strategic customization process that can proactively react to customer requests. The design process represents a virtual product line that approaches the goal of providing infinite variety at minimal costs. The process provides a base for a true customization approach, which is different from the typical mass customization approach to provide ample but limited product variety a priori for a targeted market. In this paper, we describe the development of a prototypical custom product specification system and the underlying strategic design process that is based on a collection of product platforms. The development is illustrated using an example from on-going research with a company that produces customized valves for the power industry.
Web-Based Knowledge Elicitation and Application to Planned Experiments for Product Development
Authors: Dupplaw David , Brunson David , Vine Anna-Jane E. , Please Colin P. , Lewis Susan M. , Dean Angela M. , Keane Andy J. , Tindall Marcus J.
Published: June 2008

When planning experiments to examine how product performance depends on the design, manufacture and environment of use, there are invariably too few resources to enable a complete investigation of all possible variables (factors). Here we describe a web-based system for eliciting company knowledge into an efficient two-stage group screening method. The method investigates the effect of a large number of factors by grouping them in a first stage experiment whose results identify factors to be further investigated in a second stage. Central to the success of the procedure is ensuring that the factors considered, and their grouping, are based on the best available knowledge of the product. We present a web-based software system that allows information and ideas to be contributed by engineers at different sites and uses these expert opinions to guide decisions on the planning of group screening experiments. The software includes elements that predict the total resource needed for the experiment It also simulates the results of the experiment and estimates the likely percentage of important or active factors that fail to be detected. The approach is illustrated through the planning of an experiment on engine cold start optimization at Jaguar Cars.
Web-Assisted Knowledge-Management for Automotive Lighting Systems
Authors: Herridge Mike , Orisich John S.
Published: June 2008

Knowledge management in today’s business environment is becoming one of the paramount issues in the successful production and simulation of automotive lighting systems. No longer can a single engineer maintain all the knowledge of previous lessons learned because of the shear amount of information involved. Additionally, today’s workforce is becoming more mobile and the investment in any single employee as a repository of design knowledge and product history is not feasible. With this in mind, the availability of a central repository for all simulation related information including design guidelines, previous analyses, and current production information needs to be considered a necessity for any manufacturer. By making this information available via an intranet, any employee can access their required information without requiring the attention of individual experts.
A Remote Platform for Product Performance Evaluation in Product Development Process
Authors: Zhou Shouqin , Zhao Aiping , Chin Kwai-Sang , Yarlagadda Prasad K. D. V.
Published: June 2008

In this paper, an effective web-based solution for remote product performance evaluation is proposed. The system structure of remote product performance evaluation platform and its implementation is investigated. The Matlab Web Server environment is adopted to develop remote platform, and the evaluation of design of active magnetic bearing system (MBS) is developed as an application of remote product performance platform. The ultimate objective of product design is to develop a product that perfectly meets the demand of customers following their requirements and possible manufacturing capability. The work in this paper provides a feasible solution for remote product performance evaluation during the whole product development process. Some of the benefits of this methodology are to shorten lead-time of product development and improve efficiency of product design.
Using VPS (VoxMap Pointshell) as the Basis for Interaction in a Virtual Assembly Environment
Authors: Kim Chang E. , Vance Judy M.
Published: June 2008

Realistic part interaction is an important component of an effective virtual assembly application. Both collision detection and part interaction modeling are needed to simulate part-topart and hand-to-part interactions. This paper presents a comparison of several common collision detection algorithms and examines the VoxMap Pointshell (VPS) method as it is used in an application to evaluate proposed assembly methods. Results from several performance tests on VPS are presented. VPS was found to provide realistic collisions and physicallybased modeling interaction with excellent performance. This paper concludes by presenting how VPS has been implemented to handle multiple dynamic part collisions and two-handed assembly using the 5DT dataglove in a projection screen virtual environment.
Towards Automated Design of Multi-Piece Permanent Molds
Authors: Gupta Satyandra K. , Priyadarshi Alok K.
Published: June 2008

Multi-Piece molds, which consist of more than two mold pieces, are capable of producing very complex parts—parts that cannot be produced by the traditional molds. The tooling cost is also low for multi-piece molds, which makes it an ideal candidate for pre-production prototyping and bridge tooling. However, designing multi-piece molds is a time-consuming task. This paper describes geometric algorithms for automated design of multi-piece molds. A Multi-Piece Mold Design Algorithm (MPMDA) has been developed to automate several important mold-design steps: finding parting directions, locating parting lines, creating parting surfaces, and constructing mold pieces. MPMDA constructs mold pieces based on global accessibility analysis results of the part and therefore guarantees the disassembly of the mold pieces. A software system has also been developed and successfully tested on several complex industrial parts.
Toward Automatic Process Planning of a Multi-Axis Hybrid Laser Aided Manufacturing System: Skeleton-Based Offset Edge Generation
Authors: Eiamsa-ard Kunnayut , Liou F. W. , Landers Robert G. , Choset Howie
Published: June 2008

Even though the machining process has been integrated to the Multi-Axis Laser Aided Manufacturing Process (LAMP) System in order to get good surface finish functional parts [1], the quality of parts produced by the LAMP system is still very much dependent upon the choice of deposition paths. [2] Raster motion paths are replaced by offset spiral-like paths, which are discussed in this paper. Most commercial CAD/CAM packages are feature-based, and their use requires the effort and expertise of the user. The shape has to be decomposed into manufacturing features before the software packages can generate the paths. [3] Path planning has long been studied as discussed in this paper. There are still some problems associated with the previous algorithms and also assumptions are usually made. [6, 7, 27] An algorithm for directly generating offset edges, which can be developed to be the deposition paths, is presented in this paper. The skeleton of a layer or a slice of a 3-D CAD drawing is first generated. Based on that skeleton, the offset edges are incrementally constructed. This paper focuses on the characteristics of skeleton and offset edges as well as the construction algorithm for those edges. Simulations are used to verify this method.
Extended Hierarchical Cluster Analysis for the Decomposition of Complex Design Problems
Authors: Chen Li , Ding Zhengdong , Li Simon
Published: June 2008

This paper presents a new decomposition method for partitioning complex design problems based on an extended Hierarchical Cluster Analysis (HCA). After a complex design problem is represented using a function-parameter incidence matrix, this new decomposition method allows transforming the originally unorganized matrix into a block-angular form matrix. By means of the resulting matrix, a coordination part and design blocks can be further identified and obtained. In particular, the extended HCA plays an important role in this method, contributive to aligning all non-zero elements, also known as 1s elements, of the matrix along its main diagonal as compactly as possible. As such, a post process, called Partition Point Analysis (PPA), can be further applied to the matrix to finally form the coordination part and the related design blocks, subject to such decomposition criteria as block size and coordination size limits. A powertrain design example is employed for illustration of the decomposition method newly developed.
Topology Optimization of Multi-Component Structures via Decomposition-Based Assembly Synthesis
Authors: Lyu Naesung , Saitou Kazuhiro
Published: June 2008

A method is presented for synthesizing multi-component structural assemblies with maximum structural performance and manufacturability. The problem is posed as a relaxation of decomposition-based assembly synthesis [1,2,3], where both topology and decomposition of a structure are regarded as variables over a ground structure with non-overlapping beams. A multi-objective genetic algorithm [4,5] with graph-based crossover [6,7,8], coupled with FEM analyses, is used to obtain Pareto optimal solutions to this problem, exhibiting trade-offs among structural stiffness, total weight, component manufacturability (size and simplicity), and the number of joints. Case studies with a cantilever and a simplified automotive floor frame are presented, and representative designs in the Pareto front are examined for the trade-offs among the multiple criteria.
Quantitative Exploratory Techniques to Simplify Multiple Objectives in Product Design Optimization
Authors: Ferryanto Liem , Sudjianto Agus , Vora Mahesh
Published: June 2008

The objective of this paper is to develop techniques to sub-group multiple responses of a system. The proposal is intended for explorative preprocessing steps prior to the execution of a more formal multi-objective optimization. The sub-grouping techniques are developed based on orthonormal expansions. Factor Analysis (FA) and Total Sensitivity Analysis (TSA) are suggested when the relationships among responses are linear and non-linear, respectively. Automotive road Noise Vibration and Harshness (NVH) data is used to illustrate the application of the proposed methodologies.
Multi-Objective Optimisation of Ship Hull With Distributed Applications
Authors: Giassi Alessandro , Bennis Fouad , Maisonneuve Jean-Jacques
Published: June 2008

In the context of concurrent engineering, this paper presents a quite innovative approach to the collaborative optimisation process, which couples a multi-objective genetic algorithm with an asynchronous communication tool. To illustrate this methodology, three European companies’ collaboration on the optimisation of a ship hull is described. Our study demonstrates that when multi-objective optimisation is carried out in a distributed manner it can provide a powerful tool for concurrent product design.
A Study of Geometric Error Measurement of CNC Machine Tools Using the Improved Planar Encoder System
Authors: Jywe Wen-Yuh , Liu Chien-Hong
Published: June 2008

This paper presents a useful measuring method for rapidly verifying geometric errors using a double-readheads planar encoder system (DRPES). With the calculated model and the various specified test paths, the proposed measuring method provide the rapid performance, simplicity of setup, low cost and pre-process verification of CNC machine tools. Complete setups and procedures for geometric error verification are clearly presented. Experimental results showed that more information on analyzing the types of errors can be obtained and the performance of verification can be further improved. The proposed system completes the geometric verification of a CNC machine tool within one hour.
Reducing Cycle Time and Errors in the Design and Layout of MEMS
Authors: Cherry Michael S. , Roach Gregory M. , Wittwer Jonathan W. , Howell Larry L. , Cox Jordan J.
Published: June 2008

A design methodology is presented which decreases cycle time and opportunities for error through automated execution of a consistent design procedure. The Product Design Generator (PDG) methodology is useful for existing devices with a well-established design process. Two such examples are given, the Thermomechanical In-plane Microactuator (TIM) and the micro force gauge. In both PDGs, the designer inputs a finite set of requirements which automatically updates parametric design models. The necessary analyses are then executed, and product artifacts such as a CAD file, technical document, and test procedures are generated. The application of this method reduces the opportunities for error by ten times for the TIM PDG and five times for the micro force gauge PDG. The design cycle time is reduced from hours to minutes for both devices.
Shape Knowledge Indexing Using Invariant Shape Code
Authors: Wang Chensheng , Vergeest Joris S. M. , Wiegers Tjamme , Song Yu
Published: June 2008

Shape knowledge indexing is crucial in both design reuse and knowledge engineering, in which the pivot issue is to establish the unique representation of the invariant shape properties. Treating the shape of the region of interest as a surface signal, in this paper, a local shape-indexing scheme is developed by applying the affine invariant nature of the Fourier spectrum of the spatial shape distribution. The shape-coding scheme is theoretically proven being strictly invariant under affine transformations. A framework applying the invariant shape code in shape knowledge indexing is presented. Associated examples and the quantity analysis results are provided to justify the robustness, simplicity, and adaptability of the proposed shape knowledge-indexing scheme. Further, the proposed approach could be regarded as an alternative choice to represent local shape knowledge, especially for that of freeform features.
Design Optimization of a Vehicle B-Pillar Subjected to Roof Crush Using Mixed Reactive Taboo Search
Authors: Hamza Karim , Saitou Kazuhiro , Nassef Ashraf
Published: June 2008

The primary obstacle in automated design for crashworthiness is the heavy computational resources required during the optimization processes. Hence it is desirable to develop efficient optimization algorithms capable of finding good solutions without requiring too many model simulations. This paper presents an efficient mixed discrete and continuous optimization algorithm, Mixed Reactive Taboo Search (MRTS), and its application to the design of a vehicle B-Pillar subjected to roof crush conditions. The problem is sophisticated enough to explore the MRTS’ capability of identifying multiple local optima with a single optimization run, yet the associated finite element model (FEM) is not too large to make the computational resources required for global optimization prohibitive. The optimization results demonstrated that a single run of MRTS identified a set of better designs with smaller number of simulation runs, than multiple runs of Sequential Quadratic Programming (SQP) with several starting points.
Response Surface Methods and Pareto Optimization in Crashworthiness Design
Authors: Andersson Johan , Redhe Marcus
Published: June 2008

This paper presents a method where a multi objective optimization technique is used together with response surface methods in order to support crashworthiness design. As in most engineering design problems there are several conflicting objectives that have to be considered when formulating a design problem as an optimization problem. Here this is exemplified by the desire to minimize the intrusion into the passenger compartment area and simultaneously obtain low maximum acceleration during vehicle impact. These two objectives are naturally conflicting, since low maximum acceleration implies large intrusion. The contribution of this paper is to show a successful application of a set of existing methods to solve a real world engineering problem. The paper also presents methods of illustrating the results obtained from the multi-objective optimization.
Penalized Likelihood Kriging Model for Analysis of Computer Experiments
Authors: Li Runze , Sudjianto Agus
Published: June 2008

Kriging is a popular metamodeling technique for analysis of computer experiment. However, the likelihood function near the optimum is flat in some situations, and this may lead to very large random variation in the maximum likelihood estimate. To overcome this difficulty, a penalized likelihood approach is proposed for the kriging model. The proposed method is particularly important in the context of a computationally intensive simulation model where the number of simulation runs must be kept small. We demonstrate the proposed approach for the reduction of piston slap, an unwanted engine noise due to piston secondary motion. Issues related to practical implementation of the proposed approach are discussed.