bluuebunny/crossref_metadata_2025 huggingface dataset:
Considering the Info-Gap Approach to Robust Decisions Under Severe Uncertainty in the Context of Environmentally Benign Design
Authors: Duncan Scott J. , Aughenbaugh Jason Matthew , Paredis Christiaan J. J. , Bras Bert
Published: June 2008

Information-Gap Decision Theory (IGDT), an approach to robust decision making under severe uncertainty, is considered in the context of a simple life cycle engineering example. IGDT offers a path to a decision in the class of problems where only a nominal estimate is available for some uncertain life cycle variable that affects performance, and where there is some unknown amount of discrepancy between that estimate and the variable’s actual value. Instead of seeking maximized performance, the decision rule inherent to IGDT prefers designs with maximum immunity (info-gap robustness) to the size that the unknown discrepancy could take. This robustness aspiration is subject to a constraint of achieving better than some minimal requirement for performance. In this paper, an automotive oil filter selection design example, which involves several types of severe uncertainty, is formulated and solved using an IDGT approach. Particular attention is paid to the complexities of assessing preference for robustness to multiple severe uncertainties simultaneously. The strengths and limitations of the approach are discussed mainly in the context of environmentally benign design and manufacture.
On Design and Performance of Internal Epitrochoidal Pumps
Authors: Mimmi Giovanni , Bonandrini Giovanni
Published: June 2008

In this study an analysis of rotor profiles geometry in internal epitrochoidal pumps and a systematic study of their performance as a function of the geometrical parameters are introduced. Internal pumps are used in various fields, like automotive, alimentary, or medical-scientific. This machines consist of two rotors: generally the inner rotor has epitrochoidal profile and the profile of the outer rotor is determined as conjugate to the inner one. The rotor geometry and the final performance of the whole machine has been studied by many researchers, using different methods. In this paper the construction of the profiles is performed by the theory of gearing, in order to calculate performance indexes. In particular the pump type with epitrochoidal outer rotor has been considered. Even if it is impossible to establish an optimal profile valid for every application, the analysis of the results obtained allows to choose the design parameters, in order to optimize the shape of the rotors for any particular application.
Surrogate Model Updating Using Clustering in a Genetic Algorithm Setup
Authors: Shao Tiefu , Krishnamurty Sundar
Published: June 2008

This paper addresses the critical issue of fidelity in simulation-based design optimization using preference-based surrogate models. Specifically, it presents an integrated clustering-based updating procedure in a genetic algorithm setup to iteratively improve the efficacy of Kriging models. A potential drawback of using preference-based surrogate models in simulation based design is that the surrogates may misrepresent the true optima if the model building schemes fail to capture the critical points of interest with enough fidelity or clarity. This work addresses this vulnerability and presents an efficient clustering-technique integrated surrogate model updating procedure that can capture the buried, transient, yet inherent data pattern in the evolution progression of design candidates within a genetic algorithm setup, and screen out distinct optimal points for subsequent sequential model validation and updating. The results show that the successful finding of the true optimal design through cost-effective surrogate-based optimization depends not only on the selection of sampling schemes such as sample rate and distribution in the initial surrogate model build-up, but also on an efficient and reliable updating procedure that can prevent suboptimal decisions.
Exploring the Advantages of Materials Design in a Product Design Process
Authors: Muchnick Hannah , Thompson Stephanie C. , Samadiani Emad , Allen Janet K. , Joshi Yogendra , Mistree Farrokh
Published: June 2008

In this paper, we explore the benefits of materials design in a product design process. We also compare the methods of material selection and materials design by demonstrating two examples—the design of a cantilever beam for minimum weight and the design of a fan blade for minimum weight. The design of the cantilever beam is carried out using Ashby’s material selection method as well as a proposed method for materials design. The design of the fan blade and its material is completed using computational tools. Our goal in this paper is to demonstrate the benefits of materials design over material selection methods and to illustrate the flexibility inherent in materials design processes. We are more interested in revealing the possibilities of materials design, rather than the specific results from the example problems. The investigation of materials design presented in this paper moves us one step closer towards the realization of a systematic, inductive method for the concurrent design of products and materials.
Modeling Implications in Simulation-Based Design of Stents
Authors: Shao Tiefu , Krishnamurty Sundar
Published: June 2008

Variations associated with stenting systems, artery properties, and doctor skills necessitate a better understanding of coronary artery stents so as to facilitate the design of stents that are customized to individual patients. This paper presents the development of an integrated computer simulation-based design approach using engineering finite element analysis (FEA) models for capturing stent knowledge, utility theory-based decision models for representing the design preferences, and statistics-based surrogate models for improving process efficiency. Two focuses of the paper are: 1) understanding the significance of engineering analysis and surrogate models in the simulation-based design of medical devices; 2) investigating the modeling implications in the context of stent design. The study reveals that the advanced nonlinear FEA software with analysis capacities on large deformation and contact interaction has offered a platform to execute high fidelity simulations, yet the selection of appropriate analysis models is still subject to the tradeoff between cost of analysis and accuracy of solution; the cost-prohibitive simulations necessitate the employment of surrogate models in subsequent multi-objective design optimization. A detailed comparison between regression models and Kriging models suggests the importance of sampling schemes in successfully implementing Kriging methods.
Determination of Ranged Sets of Design Specifications by Incorporating Heterogeneous Design Capability Information
Authors: Lui Huibin , Chen Wei , Scott Michael J. , Qureshi Khurshid
Published: June 2008

Setting design specifications (targets) is a critical task in the early stages of a design process. Flexible targets can accommodate uncertainty and changes in design by postponing design commitments and preserving design freedom. In this work, a new and efficient method for obtaining a ranged set of design specifications that meets the overall design goal while incorporating heterogeneous design capability information is developed. Our proposed method involves two important aspects. First, a quantization algorithm based on rough set theory is used to decompose a design attribute space into subregions based on how well they meet the overall design goal. Second, a new design flexibility measure is used as a metric to select the most desired “target region” based on both the size of the region and the design capability information retrieved from potential design concepts. Our approach captures heterogeneous design capability information in the design attribute space and enhances the ability to adapt to evolving design knowledge as well as unexpected changes. The proposed method is much more efficient than conventional optimization algorithms for solving such problems. The proposed method is demonstrated by a numerical example and the design of a domestic blender.
Development of Distributed Computing Framework for Parallel Multi-Disciplinary Optimization
Authors: Yu Chan , Liu Nan , Pochiraju Kishore , Manoochehri Souran , Ko K. H.
Published: June 2008

This paper discusses the detailed design and development of a web based parallel multi-disciplinary optimization (PMDO) framework in the distributed computing environment. This system consists of the HTTP server, the XML parser and the communication module based on TCP/IP, and is built around a computational kernel called the ACES kernel, which provides powerful computation and evaluation capabilities as well as optimization routines specifically designed for engineering purposes. We formulate and subdivide an optimization problem into several sub-problems such that one node is designated as a master which solves the overall problem and the others are distributed to client nodes each of which handles each independent sub-optimization problem. In the iteration to solve the overall optimization problem, the master forwards necessary data to each client for updated values which are the solutions of sub-optimization problems and collects the results from all the client nodes. The master continues the iteration until the optimum is reached. All optimization problems are represented in XML form and provided as input to the master and each client node.
Exploration in the Preliminary Mechanical Design of Trade-Offs Between Automotive Architectural Constraints and Aggregate Noise Performances
Authors: Hamdi Abdelbasset , Yannou Bernard , Landel Eric
Published: June 2008

This paper deals with the preliminary design of large complex mechanical products. It gives a new way to lead tradeoffs between architectural constraints and mechanical performances. While topology optimization and structural optimization have been widely developed in the last two decades [1], they are still not adapted to take into account the problem of volume allocation in the preliminary design of large and complex mechanical systems as automotive vehicles and aircrafts. New approximate criteria to assess the compliance of architectural constraints and important mechanical performances like contributions to noise are proposed. These criteria are assembled within a sole performance metamodel that embeds most of decision issues usually discussed in the preliminary design stage and which allows to encompass the strict traditional volume allocation process. Through the use of Pareto techniques, we show that it is convenient and relevant to explore the design space by allowing great variation of the design morphology. The trade-offs are made possible since the stage of volume allocation and automotive architects can be helped by tools for leading quantitative negotiations in preliminary design.
Assessing and Improving Commonality and Diversity Within a Product Family
Authors: Alizon Fabrice , Shooter Steven B. , Simpson Timothy W.
Published: June 2008

At a time when product differentiation is a major indicator of success in the global market, each company is looking to offer competitive and highly differentiated products. This differentiation issue is restricted by the design of platform-based products that share modules and/or components. It is not easy to differentiate products in a market that is often overwhelmed by numerous options. A platform-based approach can be risky because competition in the global market can become an internal competition among similar products within the family if there is not enough differentiation in the family. Thus, the goal for the product platform is to share elements for common functions and to differentiate each product in the family by satisfying different targeted needs. To assess commonality in the family, numerous indices have been proposed in the literature. Nevertheless, existing indices focus on commonality and reflect an increase in value when commonality increases but do not positively reflect an increase in the value as a result of diversity; hence, the Commonality versus Diversity Index (CDI) is introduced in this paper to assess the commonality and diversity within a family of products or across families. The CDI has variable levels of depth analysis to help designers design or improve the product family. Two case studies using single-use cameras and power tool families highlight the usefulness of this new index.
Understanding the Effects of Model Uncertainty in Robust Design With Computer Experiments
Authors: Liu Jun , Apley Daniel W. , Chen Wei
Published: June 2008

The use of metamodels in simulation-based robust design introduces a new source of uncertainty that we term model interpolation uncertainty. Most existing approaches for treating interpolation uncertainty in computer experiments have been developed for deterministic optimization and are not applicable to design under uncertainty. With the randomness present in noise and/or design variables that propagates through the metamodel, the effects of model interpolation uncertainty are not nearly as transparent as in deterministic optimization. In this work, a methodology is developed within a Bayesian framework for quantifying the impact of interpolation uncertainty on robust design objective. By viewing the true response surface as a realization of a random process, as is common in kriging and other Bayesian analyses of computer experiments, we derive a closed-form analytical expression for a Bayesian prediction interval on the robust design objective function. This provides a simple, intuitively appealing tool for distinguishing the best design alternative and conducting more efficient computer experiments. Even though our proposed methodology is illustrated with a simple container design and an automotive engine piston design example here, the developed analytical approach is the most useful when applied to high-dimensional complex design problems in a similar manner.
A Framework for Three Dimensional Solid Model Reconstruction
Authors: Mehta Chandresh , Kesavadas Thenkurussi
Published: June 2008

3D object construction by reverse engineering falls into two categories: surface reconstruction and solid model reconstruction. The 3D surface reconstruction techniques are intended to extract only the geometric information from the measured point cloud and are commonly used in computer graphics and computer vision, whereas the 3D solid model reconstruction techniques are expected to extract the geometric as well as the topological information from the measured point cloud and has application in the field of CAD/CAM. This paper presents a novel framework for 3D solid model reconstruction, which will enable reconstruction of a B-rep model of a physical object based on the 3D point cloud data captured from the surface of the object. In this framework, we use a magnetic position sensor for measuring the data from the surface of the object. This has numerous advantages over conventional methods of data acquisition that use laser scanner or coordinate measuring machine. For segmenting the measured point cloud data into sub-regions, a non-iterative region growing algorithm is developed and implemented. Our surface detection scheme is based on a Modified Gaussian image (MGI) of the sub-region and least-square techniques are used for fitting a surface to the points in a sub-region. The reconstructed B-Rep model is stored in an ISO 10303 (STEP) file format so that it can be imported in to standard CAD/CAM systems for future modifications or analysis.
An Innovative Web Application for Design and Automated NC Code Generation
Authors: Motipalli V. V. Satish K. , Krishnaswami Prakash
Published: June 2008

With the ever-increasing importance of e-commerce/e-business in the manufacturing, traditional standalone CAD/CAPP applications are evolving into web-based applications deployed via the Internet. This paper presents a unique web-based application for automated process planning and NC code generation for mill-turn parts. The application is targeted at a wide range of users. It requires no special software or CAD package at the user’s end, and can be used even by people with virutally no manufacturing knowledge. At the same time, it is also a valuable service for manufacturing experts. This application uses client/server architecture and is developed using Java technologies. This web-based application can be accessed via Internet using any standard web browser with JRE (Java run-time environment), and Java Web Start is used to deploy this application. For wide usability, the application supports easy part specification and automated process planning. Once the part is designed, the user may request NC code generation. The process planning kernel on the server automatically executes all process planning tasks like machinable volume identification, operations sequencing, parameter selection, etc. and generates an intermediate Cutter Location (CL) code. The Cutter Location code is quite generic and can be adapted for any machine using the respective post processors. The interface is also capable of displaying the tool path for verification. The NC code is generated based on the post processor selected by the user and can be downloaded to the client machine if the user is satisfied. It is hoped that this application will develop into a pay-per-use instant NC code generation web service for novices and experts; such a service is currently not offered anywhere on the Internet.
Enhancement of the Vehicle Suspension Performance Using Motion-Doubling Linkage Mechanisms
Authors: Rastegar Jahangir , Jorabchi Kavous , Park Hee J.
Published: June 2008

In recent studies, a new class of planar and spatial linkage mechanisms was presented in which for a continuous full rotation or continuous rocking motion of the input link, the output link undergoes two continuous rocking motions. Such linkage mechanisms were referred to as the “motion-doubling” linkage mechanisms. This class of mechanisms was also shown to generally have dynamics advantage over regular mechanisms designed to achieve similar gross output motions. In the present study, the use of the motion-doubling linkage mechanisms in the construction of vehicle suspension systems is investigated. The performance of the resulting vehicle suspension system is compared to that of a suspension system regularly used in vehicles. For a typical set of vehicle and tire parameters, the parameters of both suspension systems are optimally determined with a commonly used objective function, which is defined as the standard deviation of the vertical acceleration of the vehicle. Using numerical simulation, it is shown that the suspension system constructed with a motion-doubling linkage mechanism has a significantly better performance as compared to a standard suspension system.
Ontologies for Supporting Engineering Design Optimization
Authors: Witherell Paul , Krishnamurty Sundar , Grosse Ian R.
Published: June 2008

This paper presents an optimization ontology and its implementation into a prototype computational knowledge base tool dubbed ONTOP (ONTology for OPtimization). Salient features of ONTOP include a knowledge base which incorporates both standardized optimization terminology, formal method definitions, and often unrecorded optimization details, such as any idealizations and assumptions that may be made when creating an optimization model, as well as the model developer’s rationale and justification behind these idealizations and assumptions. ONTOP was developed using Prote´ge´, a Java-based, free open-source ontology development environment created by Stanford University. Two engineering design optimization case studies are presented. The first case study consists of the optimization of a structural beam element and demonstrates ONTOP’s ability to address the variations in an optimal solution that may arise when different techniques and approaches are used. A second case study, a more complex design problem which deals with the optimization of an impeller of a pediatric left ventricular heart assist device, demonstrates the wealth of knowledge ONTOP is able to capture. Together, these test beds help illustrate the potential value of an ontology in representing application-specific knowledge while facilitating both the sharing and exchanging of this knowledge in engineering design optimization.
Motion Control and Design of an Aerial Robotic System
Authors: Nikkhah Mehdi , Ashrafiuon Hashem , Dougherty Edmond J.
Published: June 2008

This research examines the dynamics and control of an aerial robotic system to determine its feasibility and general design features. The robotic system consists of a cable driven trolley and a camera platform suspended and controlled by six cables designed in a configuration similar to the Stewart platform. The camera and trolley cables are driven through winches controlled by electric motors. An algorithm is developed based on the sliding mode approach to simultaneous control the trolley trajectory and the full three-dimensional camera linear and rotational motion. Trolley cable flexibility and fundamental vibration mode is included in the analysis though not directly controlled at this stage. Wind forces are also included in the model as unknown but bound disturbances. A working prototype of the system has also been developed and its general features are introduced in this paper.
A Mesh-Based Geometric Modeling Method for General Structures
Authors: Chen Yong
Published: June 2008

This paper presents a mesh-based geometric modeling method to create tessellated models of general structures, which can be the design results of conformal truss structure design, thermal design, topology design, material design, compliant mechanism design and others. A general structure configuration design format is proposed to describe the structures. A universal structure generating system is developed based on the mesh-based geometric modeling method. Besides generating a watertight surface model for an input structure configuration, the modeling approach can automatically add an important design feature, fillets, in the generated model. Therefore the structures’ mechanical performance is improved comparing to results generated by other methods. Examples from different structure design areas are presented. The validity of the generated models is verified by using an additive manufacturing system. The computational efficiency of the method is also discussed.
Introduction of a Data Schema: The Inner Workings of a Design Repository
Authors: Bohm Matt R. , Stone Robert B. , Simpson Timothy W. , Steva Elizabeth D.
Published: June 2008

This paper describes the fundamental pieces of design information that compose the University of Missouri Rolla’s (UMR) design repository schema. Knowledge-based systems along with similar design information-capture schemas are reviewed. Repository schema conventions and specific implementation details are outlined to provide an understanding of the system connections and information relationships. Next, the repository schema is divided into seven main categories of design information including: artifact-, function-, failure-, physical-, performance-, sensory- and media-related information types. Each of the seven types of design information are described in detail to illustrate what elements of design information are recorded and how their relationships are established. An overview of the entire repository database is also presented. The result is a complete description and specification of the repository framework and allowable design information types such that the schema and repository could be recreated. Finally, a brief comparison is made between the UMR repository and its antecedent NIST repository framework.
Design for Lean Manufacturing: Incorporating Lean Considerations During Product Development
Authors: Pavnaskar S. J. , Weaver D. , Gershenson J. K.
Published: June 2008

Lean has become a “must-use” philosophy for businesses today. Lean manufacturing focuses on the elimination of waste in manufacturing operations. Similarly, companies have started using lean engineering to eliminate wastes from their engineering processes. Both lean manufacturing and lean engineering yield dramatic improvements in quality, cost, and delivery. However, the philosophy of lean (manufacturing and engineering) revolves around the continuous improvement of existing processes. Costs associated with continuous improvement can be significantly reduced by incorporating “lean” considerations when designing a product, process, or manufacturing system. This is known as design for lean manufacturing (DfLM). DfLM guides the design of a product, process, or a manufacturing system to enable lean operations when in production, just as design for assembly (DFA) guides the design of a product to allow easier assembly during production. Currently, there are no guidelines that would help a product or process designer in considering to lean operations during design. Note that usage of the word “product” in this paper must be interpreted in a literary sense and not as a “widget.” The “product” of a manufacturing engineering process is a complete manufacturing system. In this paper, we consider manufacturing system design and propose a novel set of structured DfLM guidelines for designing a manufacturing system. These guidelines will be a valuable resource for manufacturing engineers to guide manufacturing system design for new products to enable lean operations once the system is in production. DfLM guidelines for system design also will help plant engineers and rapid continuous improvement managers to assess existing manufacturing systems and identify and prioritize improvement efforts. The proposed DfLM guidelines are then validated for accuracy, completeness, and redundancy by using them to evaluate an existing benchmark manufacturing system. The initial DfLM guidelines show promise for use in designing manufacturing systems that are easy to manage, flexible, safe, build quality into the products, optimize material flow, fully utilize all resources, maximize throughput, and continuously produce what the customer wants just in time. Similar guidelines can be proposed for product and process design to further enhance the efficiency of operations and reduce the overhead of continuous improvement efforts.
Differential Geometry Based Analysis and Synthesis of a Multifingered Robotic Hand With a Metamorphic Palm
Authors: Dai Jian S. , Wang Delun
Published: June 2008

This paper presents a novel robotic hand with a metamorphic palm which changes the traditional structure of a robotic hand. Based on this new hand structure, the paper investigates motion of robotic fingers with respect to the palm by introducing finger operation-planes and by revealing the relationship between finger motion and palm motion. The study presents normals of the finger operation-planes as function of the input angle of the palm and relates finger motion to palm motion. This leads to the co-axial condition of the finger-palm relationship that is then converted to the coplanar condition of normals of all finger operation-planes. The paper then maps the known normals of the first two finger operation-planes to a spherical image space and produces the Gaussian image of normals and a cone of a normal, leading to differential geometry based analysis of the normals of the operation planes and synthesis of the metamorphic palm.
Remanufacture Dependency Matrix and Market Diffusion of Multi-Level Products
Authors: Pandey Vijitashwa , Thurston Deborah , Jolly Mohit
Published: June 2008

Many products exhibit remanufacturability at more than one level i.e. their components can not only be used to manufacture a repeat product, they can also be used to manufacture simpler products. While such Multi-Level Remanufacturable Products (MLRPs) have shown promise in terms of cost savings and environmental benefits, no design methods are available which include consideration of these simpler, derivative products. This paper introduces the Remanufacture Dependency Matrix (RDM) as a metric of remanufacturability of a product to account for the possibility of it being remanufactured into simpler products. Although the derivative products depend on the parent product for components, they don’t necessarily compete with it in the marketplace. While diffusion of products in the market in their first lifecycle is fairly understood, there is limited literature on diffusion characteristics incorporating subsequent lifecycles especially in the MLRP scenario. This paper also proposes a variation on the Bass diffusion model to investigate the effects of different levels of remanufacturability. A case study regarding the use of components from personal computers to manufacture book reading devices is presented to exemplify the approach. Our results show that profits can be increased while reducing the environmental impact at the same time.
Introducing Hierarchical Particle Swarm Optimization to Optimal Part Orientation in Fused Deposition Modeling
Authors: Ghorpade Amol , Dashroa Yogesh , Tiwari M. K. , Karunakaran K. P.
Published: June 2008

This article presents hierarchical particle swarm optimization algorithm to determine optimal part orientation for the complex parts produced by fused deposition modeling. Owing to the importance of efficient prototyping during product development phase, it is necessary to address critical issues involved in fused deposition modeling. The best part orientation is explored by taking into account volumetric error, build cost and orientational efficiency in the form of an aggregate objective. This paper exploits the search efficiency exhibited by hierarchical particle swarm optimization (HPSO), an optimization algorithm working on the basis of swarm intelligence, with the aim to resolve underlying optimal part orientation (OPO) problem. Further, in order to establish efficacy of HPSO a comparative study has been performed with a genetic algorithm based search. The results indicate outperforming behavior of HPSO and thus it is claimed to be a viable and efficient alternative to OPO problem.
Improving an Existing Product Family Based on Commonality/Diversity, Modularity, and Cost
Authors: Alizon Fabrice , Shooter Steven B. , Simpson Timothy W.
Published: June 2008

As product life cycles become shorter and shorter, stakes are higher in terms of sales and profits, making it an imperative for companies to enhance existing product families as much as possible. Redesigning a family of products can become a difficult task when considering the number of variables (products, modules, components, etc.), competing objectives (diversity-commonality, cost-variety, etc.), and actual technical solutions (cost value, architectural constraints), etc. In this paper, a methodology using the Design Structure Matrix flow (DSMflow), Value Analysis (VA), and the Commonality versus Diversity Index (CDI) is proposed to improve an existing family of products. These three tools enable the assessment and the improvement of (1) commonality and diversity within the family, (2) feature satisfaction through design, and (3) definition of new modules/components and their interfaces. A case study based on a family of refrigerators (including CAD models) is detailed in this paper to demonstrate the methodology. The proposed methodology supports both the reengineering of an existing family and can also be extended to benefit the early development stages when designing a new family of products.
Assessing and Increasing Product and Family Differentiation in the Market
Authors: Alizon Fabrice , Shooter Steven B. , Simpson Timothy W.
Published: June 2008

To help guarantee profit and stability in today’s global market, companies must focus on the differentiation of their products. Successfully differentiated products will attract customers, generate revenue and benefit the brand image, whereas a banal product can lose money and leave a bad impression in the market. Many large companies have recently lost significant market share in part due to poor product differentiation. This paper introduces four indices to assess this differentiation at two levels—family and market—based on product function and function attributes. At the family level, the Product Differentiation Index (PDI) assesses the differentiation between a product and other products in the rest of the family and also the differentiation within the family. At the market level, the Family Differentiation Index (FDI), Family Coverage Index (FCI), and Family Un-coverage Index (FUI) assess the differentiation, the coverage, and the un-coverage of a family with another, and/or with the rest of the market, respectively. These indices help designers and marketers evaluate the positioning of their products and support product family planning. A case study involving two competitive single-use camera families is presented.
Including Human Behavior in Product Simulations for the Investigation of Use Processes in Conceptual Design: A Survey
Authors: Van der Vegte Wilhelm F. , Horva´th Imre
Published: June 2008

In this paper, approaches for behavioral simulation of humans and human-artifact systems are reviewed The objective was to explore available knowledge for the development of a new method and system for the simulation of use processes of consumer durables in conceptual design. A key issue is to resolve the trade-off between minimizing the modeling and computing effort on the one hand, and maximizing the amount of valuable information obtained from simulations to facilitate improving the product. After drawing up review criteria, we reviewed existing simulation approaches, which we characterized based on the simulation models. We found that the surveyed approaches can only address limited, largely unconnected subsets of the various behaviors that can be simulated. For the most advanced approaches, the subsets can be clustered into three main groups: (i) kinematics and rigid-body kinetics simulated with non-discretized object models, (ii) mechanical-deformation behavior and non-mechanical physical behavior simulated with discretized object models and (iii) interpreted physical behavior (information processing) simulated with finite-state machines. No clear-cut solutions for integrated behavioral simulation of use processes have been found, however, we could identify opportunities to bridge the gaps between the three groups of behavior, which can help us to resolve the aforementioned trade-off. In the first place, it seems that the possibilities for using discretized models in kinematics simulation (especially with consideration of the large deformations that are common in biomechanics) have not been fully explored. Alternatively, a completely new uniform modeling paradigm, possibly based on particles, might also help to resolve the gap between the two distinct groups of physical behaviors. Finally, hybrid simulation techniques can bridge the gap between the observed physical behaviors and interpreted physical behaviors. Here, the combination with the object models commonly used for simulations in group (i) and (ii) seems to be largely unexplored. Our findings offered valuable insights as a starting point for developing an integrated method and system for modeling and simulating use processes. We expect that other researchers dealing with similar issues in combining seemingly disconnected simulation approaches could benefit as well.
Feature Technology and Ontology for Embedded System Design and Development
Authors: Zha Xuan F. , Sriram Ram D.
Published: June 2008

In this paper, we present our recent effort on using feature technology and ontology for embedded systems modeling and design. We present an overview of embedded system design and propose an object-oriented UML modeling approach to representing embedded systems, i.e., open embedded system model (OESM). OESM supports models of embedded system artifacts, components, features, configuration/assembly, and embedded system platform and family, design rationale, etc. Our focus is on modeling of feature semantic in embedded systems. We call this open embedded system feature model (OESFM). We also present a semantic web environment for modeling and verifying feature models using ontologies, in which the Prote´ge´-OWL is used to precisely capture the relationships among features in feature diagrams and configurations. The OESFM models and ontologies provide a feature-based component collaborative framework. This allows the designer to develop a virtual embedded system prototype through assembling virtual components in which the platform-based HW/SW co-design is supported and the design rationale is captured. The collaborative co-design framework can not only provide formal precise models of the embedded system prototypes but also offers design variation of prototypes whose members are derived by changing certain virtual components with different features.
Enhanced Convergence in Distributed Design Processes
Authors: Gopalakrishnan Jayaram , Singh Tarunraj , Lewis Kemper
Published: June 2008

The focus of this paper is on studying the convergence properties of the solution process of decentralized or distributed subsystems, where each subsystem has its own design problem, including objective(s), constraints, and design variables. The challenging aspect of this type of problem comes in the coupling of the subsystems, which create complex research and implementation challenges in modeling and solving these types of problems. We focus on the dynamics of these distributed design problems and attempt to further the understanding of the fundamental mechanics behind these processes in order to support the decisions being made by a network of decision makers. In this work, the domain of attraction, or region where convergence to a stable equilibrium point is guaranteed, of a decentralized design process is studied. Two approaches based on concepts from nonlinear control theory are presented: the first determines the domain of attraction for a specified Lyapunov function and the second optimizes for a Lyapunov function which maximizes the domain of attraction. The two techniques are illustrated on a benchmark pressure vessel design problem.
Automating Redesign of Sheet-Metal Parts in Automotive Industry Using KBE and CBR
Authors: Sandberg Marcus , Larsson Tobias
Published: June 2008

Automating redesign is an approach for engineering designers to prevent design related manufacturability problems in early product development and thus reduce costly design iterations. A vast amount of work exists, with most research findings seemingly staying within the research community rather than finding its way into use in industrial settings where research issues have often evolved from the concerned applied research. The aim of this paper is to present an approach with industrial implementation potential regarding automating redesign of sheet-metal components in early product development to avoid manufacturing problems due to design flaws and non-optimal designs. Geometry, generated by a knowledge-based engineering (KBE) system, gives input to the case-based reasoning (CBR) governed manufacturing planning. If geometry is found non-manufacturable or enhancement of already manufacturable geometry is possible, the CBR system will suggest redesign actions to resolve the problem. CBR extends the capabilities of the rule-based KBE-system by enabling plan-based evaluation. The approach has the potential for industrial implementation, since KBE is often closely coupled to an industrial CAD-system, hence enabling technology is at the industry. Also, combining KBE and CBR reduces the coding effort compared to coding the whole design support with CBR, as feature recognition is simplified by means of KBE. A case study of development of sheet-metal manufactured parts at a Swedish automotive industry partner presents the method in use. As it is shown that redesign can be automated for sheet-metal parts there is a potential for reducing costly design and manufacturing iterations.
Algorithms for On-Line Monitoring of Components in an Optical Tweezers-Based Assembly Cell
Authors: Peng Tao , Balijepalli Arvind , Gupta Satyandra K. , LeBrun Thomas W.
Published: June 2008

Optical tweezers have emerged as a powerful tool for micro and nanomanipulation. Using optical tweezers to perform automated assembly requires on-line monitoring of components in the assembly workspace. This paper presents algorithms for estimating positions and orientations of microscale and nanoscale components in the 3-Dimensional assembly workspace. Algorithms presented in this paper use images obtained by optical section microscopy. The images are first segmented to locate areas of interest and then image gradient information from the areas of interest is used to generate probable locations and orientations of components in the XY-plane. Finally, signature curves are computed and utilized to obtain component locations and orientations in 3-D space. We have tested these algorithms with silica micro-spheres as well as metallic nanowires. We believe that the algorithms described in this paper will provide the foundation for realizing automated assembly operations in optical tweezers-based assembly cells.
Two-Stage System of Systems Model by Linking System Design With Resource Allocation
Authors: Hidalgo I. Jessica , Kim Harrison M.
Published: June 2008

Decomposition-based product design optimization under system of systems paradigm is linked with resource (i.e., product) allocation. A two-stage, system of systems approach to linking resource allocation (e.g., vehicle routing problem (VRP)) and system design optimization (e.g., vehicle design problem (VDP)) is presented. The problem inherently contains discrete variables from VRP, thus a practical formulation is presented to overcome convergence difficulty associated with shared discrete variables in a decomposed setting. Two examples, composed of four and eight air routes respectively with the introduction of a new aircraft to the existing fleet, are presented to demonstrate the effectiveness of the proposed approach. A new type of aircraft is designed and allocated to the currently existing VRP to meet the demand, while the direct operating cost of an airline is minimized.
A Computational Framework for Point Cloud Construction Using Digital Projection Patterns
Authors: Peng Tao , Gupta Satyandra K.
Published: June 2008

Many reverse engineering and inspection applications require generation of point clouds representing faces of physical objects. This paper describes a computational framework for constructing point clouds using digital projection patterns. The basic principle behind the approach is to project known patterns on the object using a digital projector. A digital camera is then used to take images of the object with the known projection patterns imposed on it. Due to the presence of 3-D faces of the object, the projection patterns appear distorted in the images. The images are analyzed to construct the 3-D point cloud that is capable of introducing the observed distortions in the images. The approach described in this paper presents three advances over the previously developed approaches. First, it is capable of working with the projection patterns that have variable fringe widths and curved fringes and hence can provide improved accuracy. Second, our algorithm minimizes the number of images needed for creating the 3-D point cloud. Finally, we use a hybrid approach that uses a combination of reference plane images and estimated system parameters to construct the point cloud. This approach provides good run-time computational performance and simplifies the system calibration.
Module Interface Representation
Authors: Bettig Bernhard , Gershenson John K.
Published: June 2008

Modular design issues are receiving increased attention by companies interested in reducing costs from carrying large numbers of components while at the same time increasing product quality and providing customers with greater product variety. Existing research has mainly focused on optimizing product platforms and product offerings, with little attention being given to the interfaces between modules. This research presents an investigation into how module interfaces are best represented in a CAD/PDM environment. The representation decisions are identified and advantages and limitations for each option are presented. Representation decisions revolve around issues such as the use of higher abstraction models, the use of ports, and referencing interface components in interface definitions. We conclude that higher abstraction models are necessary, ports should be represented explicitly, and interface hardware should not be included directly with interfaces. The research considers a large number of components from representative products offered by a home appliance manufacturer.
A Flexible System Framework for a Nanoassembly Cell Using Optical Tweezers
Authors: Balijepalli Arvind , LeBrun Thomas W. , Gupta Satyandra K.
Published: June 2008

The optical tweezers instrument is a unique tool for directed assembly of nanocomponents. In order to function as a viable nanomanufacturing tool, a software architecture is needed to run the optical tweezers hardware, provide an effective user interface, and allow automated operation. A flexible software system framework is described to utilize the optical tweezers hardware to its full potential. Initially we lay out the requirements for the system framework and define the broad architectural choices made while implementing the different modules. Implementation details of key system modules are then described. The flexible nature of the architecture is demonstrated by showing how a simulation module can be seamlessly included into the framework to replace the optical tweezers hardware as necessary. Finally, we show some representative assembly operations to demonstrate the capabilities of the system.
Crashworthiness Design Using a Hybrid Cellular Automaton Algorithm
Authors: Patel Neal M. , Kang Byung-Soo , Renaud John E.
Published: June 2008

Crashworthiness design is an evolving discipline that combines vehicle crash simulation and design synthesis. The goal is to increase passenger safety subject to manufacturing cost constraints. The crashworthiness design process requires the modeling of the complex interactions involved in a crash event. Current approaches utilize a parameterized optimization approach that requires response surface approximations of the design space. This is due to the expensive nature of numerical crash simulations and the high nonlinearity and noisiness in the design space. These methodologies usually require a significant design effort to determine an initial design. In this research, a non-gradient approach to topology optimization is developed for crashworthiness design. The methodology utilizes the cellular automata paradigm to generate a concept design.
Requirement of Compactness Pressure Constancy During the Manufacturing of Not Axialsymmetric Components by Robotized Filament Winding
Authors: Sorrentino L. , Polini W.
Published: June 2008

Robotized filament winding is a technology that involves an industrial robot placing fibres impregnated by resin along the directions of stresses the work-piece is subjected in exercise. It moves a deposition head along a winding trajectory in order to wind a tape impregnated by resin on a die. The winding tension is a very critical aspect of robotized filament winding, since it influences the compactness and the alignment of the fibres inside the composite material. The present paper underlines the problems connected to the lack of constancy of the compactness pressure during the winding of a tape on a die characterized by many different bending radii due to the complex geometry of the part to manufacture. This paper shows a study to set constant the value of the compactness pressure of the tape on the whole die. This means to assure in each point of the composite part the same value of density, percentages in volume of fibres and resin. By this study it has been possible to determine a model that is able to control in real time the tension to apply to the tape during winding or to design auxiliary devices to pre-compacting the tape on die, once deposited.