bluuebunny/crossref_metadata_2025 huggingface dataset:
First Estimates of Nonuniform Electrolyte on Seawater Corrosion Parameters
Authors: DeGiorgi V. G. , Michopoulos J. G.
Published: July 2009

All metals corrode with exposure to electrolytes. This is a fact of life experienced by owners of marine platforms and structures throughout the world. Computational modeling methodologies have been applied to evaluate and design corrosion prevention systems. All computational work to date makes similar assumptions of a uniform electrolyte. This is a valid assumption for structures in large volumes of constantly refreshing electrolyte in which the constitutive characteristics of the electrolyte can be approximated by a uniform mixture. There is experimental evidence that this assumption is not valid for smaller volumes. The need for a more general solution which is valid in these smaller enclosed spaces is being driven by future designs that place corrosion prevention systems in these areas. The sensitivity of solutions on variations in electrolyte conductivity is unknown. In this work preliminary results are presented that demonstrate the need to take into account the spatial variation in electrolyte characteristics for small enclosed volumes of electrolyte. Two geometries (a gap between plates and a two material concentric cylinder corrosion cell) are used to demonstrate the differences between uniform and spatial varying electrolyte. Future work is outlined which will take into account more physical parameters related to electrochemical corrosion.
Position and Orientation Characteristic Equation for Topological Design of Serial Mechanisms
Authors: Yang Ting-Li , Liu An-Xin , Jin Qiong , Luo Yu-Feng , Shen Hui-Peng , Hang Lu-Bin
Published: July 2009

This paper presents the explicit mapping relations between topological structure of mechanism and position and orientation characteristic (abbreviated as POC hereafter) of its motion output link. It deals with: (1) The symbolic representation and the invariant of topological structure of mechanism; (2) The matrix representation of POC of mechanism motion output; (3) The POC equation of serial mechanism and its symbolic operation rules. The symbolic operation involves simple mathematic tools and fewer operation rules, and has clear geometrical meaning. So it is easy to use. The POC equation can be used for structural analysis and synthesis of serial and parallel mechanisms. The method proposed in this paper is totally different from the methods based on screw theory and based on displacement subgroup/sub-manifold.
Rank and Mobility of Single Loop Kinematic Chains
Authors: Yang Ting-Li , Sun Dun-Jin
Published: July 2009

This paper presents a novel method for determining rank and mobility of single loop kinematic chains which is totally different from the methods based on screw theory and based on displacement subgroup. The rank of single loop kinematic chains can be determined via the position and orientation characteristic (in short, POC) equation and its symbolic operation of serial mechanism presented by authors. The symbolic operation of the POC equation is simpler and has clear geometrical meaning. The method for determining the rank of single loop kinematic chains can be used for calculating DOF of parallel mechanisms.
Analysis of Electrical Discharge Machining Using Water as Dielectric and Diverse Electrode Materials
Authors: Medellin Hugo , Flores Aaro´n , Morales Jorge , de la Garza Alonso
Published: July 2009

This paper presents an experimental investigation carried out to study the performance of electrical discharge machining (EDM) using water as dielectric. This experimentation was performed using different types of water as dielectric, several electrode materials and two different workpiece materials. The electrode materials used in the experimentation were bronze, brass, copper, aluminium and steel; and the workpiece materials used were ASTM A36 mild (low-carbon) steel and D-2 tool steel. A new desktop size EDM machine to perform the experiments was designed and is presented in this paper. After performing the experimentation, the results have shown that the best EDM performance is achieved with brass and bronze electrodes using a mixture of 75% tap and 25% deionised water as dielectric. The results also indicate that the material removal rate and the electrode wear are proportional to the source voltage used in the EDM process. Finally, a forming die with a complex shape used in a jewellery industry, was manufactured using the EDM system presented in this paper.
Study of Some Contemporary Laminar Flow Models Over a Flat Plate Using Maple
Authors: Aziz Abdul
Published: July 2009

The paper uses a modern computing tool, Maple, to study some contemporary problems in laminar boundary layer flow over a flat plate. The purpose is to demonstrate that Maple is a powerful computational tool for solving realistic contemporary problems in laminar boundary layer theory. The specific problems (all pertaining to a flat plate) chosen for this study are (1) hydrodynamic boundary layer with slip flow condition, (2) velocity boundary layer on a moving plate, (3) hydrodynamic and thermal boundary layers with a linear shear flow. Each problem is of contemporary interest and allows a similarity analysis which reduces the continuity, momentum, and energy equations into ordinary nonlinear differential equations. Numerical solutions of these equations are generated and physical interpretations of the results provided. Maple worksheets for solving each problem are available from the author upon request. It is shown that the effort required to solve these problems with Maple is modest, consisting of few lines of easily learned commands. The use of Maple facilitates and enriches the study of laminar boundary flows in general.
Determining Component Freeze Order: A Redesign Cost Perspective Using Simulated Annealing
Authors: Keller Rene , Eckert Claudia M. , Clarkson P. John
Published: July 2009

Managing design freezes plays an important part in today’s competitive markets and successful freeze management can make the difference between delivering a product in time and in budget or failed design projects. On the one hand, design managers want to limit change propagation by freezing components or component-interfaces in order to avoid unwanted change propagation and to meet design lead-times. On the other hand freezing the design of a component too early can constrain innovation and having to unfreeze a design that was frozen before can add further redesign costs. This paper introduces an algorithm for determining an optimal change freeze order (CFO) based on combined change risks and component redesign cost, which has been applied in an automotive company in the design of a diesel engine.
Enhancement of Ride Comfort Adjusting Seat Stiffness With Air-Cells
Authors: Yoo Wan-Suk , Park Dong W. , Kim Min S. , Hong Geum S.
Published: July 2009

In this paper, the ride comfort obtained from computer simulation was compared to that of physical experiment. To measure ride comfort of a passenger car, acceleration data was obtained from the floor and seat during highway running with different speeds. The measured acceleration components were multiplied by weighting functions, and then summed together to calculate overall ride values. For the computer simulation, MADYMO software was employed. To enhance ride comfort, several air cells are installed in the seat cushion to adjust the stiffness of seat by changing the air pressure in the cells. For the ride comforts, SEAT (Seat Effective Amplitude Transmissibility) was compared. To choose optimum air pressure in the cell, several test drivers with different weights were tested on several vehicle speeds.
Integrated Optimal Product Design and Process Planning for One-of-a-Kind Production
Authors: Hong G. , Dean P. R. , Yang W. , Tu Y. L. , Xue D.
Published: July 2009

One-of-a-kind production (OKP) is a new manufacturing paradigm to produce customized products based on requirements of individual customers while maintaining the quality and efficiency of mass production. In this research, an integrated optimal product design and process planning approach is developed to satisfy customer requirements considering design and manufacturing constraints. In this work, a hybrid AND-OR graph is introduced to model the variations of design configurations/parameters and manufacturing processes/parameters in generic product family. Since different design configurations and parameters can be created from the same customer requirements, and each design can be further achieved through alternative manufacturing processes and parameters, co-evolutionary genetic programming and numerical optimization are employed to identify the optimal product design configuration/parameters and manufacturing process/parameters. An industrial case study to identify the optimal design configuration/parameters and manufacturing process/parameters of custom window products in a local company is introduced to demonstrate the effectiveness of the developed method.
Kinematic Analysis and Optimization of a Novel Robot for Surgical Tool Manipulation
Authors: Zhang Xiaoli , Nelson Carl A.
Published: July 2009

The size and limited dexterity of current surgical robotic systems are factors which limit their usefulness. To improve the level of assimilation of surgical robots in minimally invasive surgery (MIS), a compact, lightweight surgical robotic positioning mechanism with four degrees of freedom (DOF) (three rotational DOF and one translation DOF) is proposed in this paper. This spatial mechanism based on a bevel-gear wrist is remotely driven with three rotation axes intersecting at a remote rotation center (the MIS entry port). Forward and inverse kinematics are derived, and these are used for optimizing the mechanism structure given workspace requirements. By evaluating different spherical geared configurations with various link angles and pitch angles, an optimal design is achieved which performs surgical tool positioning throughout the desired kinematic workspace while occupying a small space bounded by a hemisphere of radius 13.7 cm. This optimized workspace conservatively accounts for collision avoidance between patient and robot or internally between the robot links. This resultant mechanism is highly compact and yet has the dexterity to cover the extended workspace typically required in telesurgery. It can also be used for tool tracking and skills assessment. Due to the linear nature of the gearing relationships, it may also be well suited for implementing force feedback for telesurgery.
Rough Set-Based Design Rule Selection for Collaborative Assembly Design
Authors: Kim Kyoung-Yun , Choi Keunho
Published: July 2009

While the modern product development requires more knowledge-intensive and collaborative environment, the capture, retrieval, accessibility, and reusability of that design knowledge are increasing critical. In this paper, a rough set theory generates demanded rules and selects the appropriate minimal rules among the demanded design rules associated to the assembly design knowledge. The design rules are infrequently captured and often ignored due to its complexity. Rough set theory synthesizes approximation of concepts, analyzes data by discovering patterns, and classifies into certain decision classes. Such patterns can be extracted from data by means of methods based on Boolean reasoning and discernibility. This paper shows the feasibility of rough-set based rule selection considering complex design data objects in order to obtain efficient assembly design decision.
Analytical Robust Design of Mechanical Systems
Authors: Zhang Jian , Gu Peihua , Bao Nengsheng , Zhang Guojun
Published: July 2009

Based on general principles of robust design and axiomatic design, relationship among robustness, structural parameters, design parameters and uncontrollable factors has been established. Various factors that affect system robustness were analyzed mathematically to determine the relationship between robustness and structural characteristics of the linear system. The relations among functional requirements were also explored. Accordingly, an optimization model was established to determine design parameters. This new robust design approach can be used for linear mechanical system analysis.
Using Multiple Surrogates for Minimization of the RMS Error in Meta-Modeling
Authors: Viana Felipe A. C. , Haftka Raphael T.
Published: July 2009

Surrogate models are commonly used to replace expensive simulations of engineering problems. Frequently, a single surrogate is chosen based on past experience. Previous work has shown that fitting multiple surrogates and picking one based on cross-validation errors (PRESS in particular) is a good strategy, and that cross validation errors may also be used to create a weighted surrogate. In this paper, we discuss whether to use the best PRESS solution or a weighted surrogate when a single surrogate is needed. We propose the minimization of the integrated square error as a way to compute the weights of the weighted average surrogate. We find that it pays to generate a large set of different surrogates and then use PRESS as a criterion for selection. We find that the cross validation error vectors provide an excellent estimate of the RMS errors when the number of data points is high. Hence the use of cross validation errors for choosing a surrogate and for calculating the weights of weighted surrogates becomes more attractive in high dimensions. However, it appears that the potential gains from using weighted surrogates diminish substantially in high dimensions.
Dynamic Modeling of a Slider-Crank Mechanism Under Joint Wear
Authors: Mukras Saad , Mauntler Nate , Kim Nam Ho , Schmitz Tony , Sawyer W. Gregory
Published: July 2009

A study of how joint wear affects the kinematics of a simple slider-crank mechanism and in turn how change in kinematics of the mechanism affects the joint wear is presented. The coupling between joint wear and system kinematics is modeled by integrating a wear prediction process, built upon a widely used finite-element-based iterative scheme, with the dynamic model that has an imperfect joint whose kinematics changes progressively according to joint wear. Three different modeling techniques are presented based on different assumptions, and their performances are compared in terms of joint forces and wear depths. It turns out that the joint wear increases the joint force and accelerates the wear progress. The accuracy of integrated dynamic model is validated by measuring joint force and wear depth of the slider-crank mechanism. Details of instrumentation are also presented.
Stiffness Matrix of Compliant Parallel Mehanisms
Authors: Quennouelle Cyril , Gosselin Cle´ment
Published: July 2009

Starting from the definition of a stiffness matrix, the authors present the Cartesian stiffness matrix of parallel compliant mechanisms. The proposed formulation is more general than any other stiffness matrix found in the literature since it can take into account the stiffness of the passive joints and remains valid for large displacements. Then, the validity, the conservative property, the positive definiteness and the relation with other stiffness matrices of this matrix are discussed theoretically. Finally, a numerical example is given in order to illustrate the correctness of this matrix.
Incorporating Twinkling in Genetic Algorithms for Global Optimization
Authors: Ladkany George S. , Trabia Mohamed B.
Published: July 2009

Genetic algorithms have been extensively used as a reliable tool for global optimization. However these algorithms suffer from their slow convergence. To address this limitation, this paper proposes a two-fold approach to address these limitations. The first approach is to introduce a twinkling process within the crossover phase of a genetic algorithm. Twinkling can be incorporated within any standard algorithm by introducing a controlled random deviation from its standard progression to avoiding being trapped at a local minimum. The second approach is to introduce a crossover technique: the weighted average normally-distributed arithmetic crossover that is shown to enhance the rate of convergence. Two possible twinkling genetic algorithms are proposed. The performance of the proposed algorithms is successfully compared to simple genetic algorithms using various standard mathematical and engineering design problems. The twinkling genetic algorithms show their ability to consistently reach known global minima, rather than nearby sub-optimal points with a competitive rate of convergence.
Instantaneous Kinemato-Static Model of Planar Compliant Parallel Mechanisms
Authors: Quennouelle Cyril , Gosselin Cle´ment
Published: July 2009

In this paper, the number of degrees of freedom, the kinematic constraints, the pose of the end-effector and the static constraints that lead to the Kinemato-Static Model of a Compliant Mechanism are introduced. A formulation is then provided for the Instantaneous Kinemato-Static Model. This new model enables to calculate the variation of the pose as a linear function of the motion of the actuators and the variation of the external loads through two new matrices: the compliant Jacobian matrix and the matrix of compliance that give a simple and meaningful formulation of the model of the mechanism.r Finally, a simple application to a 4-bar mechanism is presented to illustrate the use of this model and the new possibilities that it opens, notably the study of the kinematics for any range of applied load.
Using Hybrid Heuristic Evaluation Method to Uncover the Conceptual Design Tasks Supported by a Holographic Display Based Truly 3D Virtual Design Environment
Authors: Opiyo Eliab Z. , Horva´th Imre
Published: July 2009

In the research reported in this paper, we investigated if a holographic display based truly 3D virtual design environment can effectively support 3D conceptual design. In this investigation, we applied heuristic evaluation method (Nielsen and Mack, 1994), but with some differences. We first conducted a literature study and compiled a comprehensive list of conceptual design tasks. We then asked selected experts to evaluate the experimental system and to indicate which conceptual design tasks can be supported. The experimental 3D design support environment consisted of a holographic display as a primary visualization device. In this experimental system, visual representation of information is presented aerially by using the holographic display, and viewers can interact with the displayed images by using the traditional input devices such as mouse and keyboard. The study established that this system can support only a handful of conceptual design tasks, in particular those requiring passive visualization such as review of the ergonomics of the product and aesthetics review. Other conceptual design tasks can be supported either partially or are not supported at all. This can be attributed in part to the shortcomings of the display, which include, for instance, poor resolution, inability of viewers to experience stereoscopic view all around the virtual object, lack of mechanism for enabling direct interaction between the viewer and the displayed virtual object, and lack of proper input mechanisms and user interfaces.
Dynamic Workspace and Control of Planar Active Tensegrity-Like Structures
Authors: Schmalz Andrew P. , Agrawal Sunil K.
Published: July 2009

This paper addresses the issues of control and workspace determination of planar active tensegrity or tensegrity-like structures. The motion of such structures is generally produced by actuated cables, which cannot tolerate compressive forces. Hence, a controller which not only satisfies the system dynamic equations, but also maintains positive tension in cables is necessary. A null-space controller based on feedback linearization theory is developed for this purpose. This controller utilizes redundant active cables to overactuate the system. The concept of a ‘dynamic workspace’ for these structures is then introduced. This workspace consists of all configurations that are achievable from a given initial configuration while maintaining positive tensions throughout the entire system motion and is a powerful tool in analyzing the performance of a variety of tensegrity structures. This idea extends the concept of the static workspace, which consists of statically maintainable configurations, by incorporating system motion and dynamics to guarantee positive tensions during transition between the states. A critical benefit of this procedure is that it may be used to find the dynamic workspace of a system regardless of whether actuator redundancy is utilized, and thus can be used to objectively illustrate the degree to which overactuation improves mobility of a tensegrity structure. The effectiveness of the developed concepts is demonstrated through computer simulation and actual physical experimentation.
Actuation Enhancement of PZT Thin-Film Membrane Actuators via Stress Relief Grooves
Authors: Lee Cheng-Chun , Cao G. Z. , Shen I. Y.
Published: July 2009

Lead Zirconate Titanate Oxide (PbZrxTi1−xO3 or PZT) is a piezoelectric material widely used as sensors and actuators. For microactuators, PZT often appears in the form of thin films to maintain proper aspect ratios. A common design is PZT membrane microactuator, whose actuation portion takes a form of a thin diaphragm driven by a PZT thin film. To maximize actuation displacements, finite element analyses are conducted to identify critical design parameters of the PZT film. In the simulation, a constant driving electric field is maintained and boundary conditions of the PZT film are varied. The finite element analyses lead to two important results. First, the actuator displacement increases as the PZT film thickness increases, but saturates at a critical PZT film thickness. Second, when stress relief grooves are introduced and the PZT film surrounding the membrane area is removed, the actuator displacement increases substantially by at least a factor of 5.
A Systematic Approach for Aligning ODE and Agent-Based Models: Application to Epidemiological Modeling
Authors: Leamy Michael J.
Published: July 2009

Recent researchers active in the field of agent-based modeling have called for the alignment, or ‘docking,’ of models which simulate the same system using different techniques. Addressing this need, the present article details a systematic approach for docking models described by (nonlinear) ordinary differential equations with analogous models employing autonomous agents — i.e., agent-based models (ABMs). In particular, the approach is demonstrated by example for an epidemiological SEIR (Susceptible, Exposed, Infectious, Recovered) ODE model with a newly-developed agent-based model. The ABM is designed such that the assumptions present in the ODE model are matched by the actions of the ABM agents and the model. In addition, less-than-transparent coefficients present in the ODE model are examined via difference equations and then mapped to appropriate agent behavior. The result is very good agreement in comparisons made between ODE and ABM model-generated time-histories — i.e., successful alignment. It is anticipated that the systematic alignment approach described herein should be useful for aligning ODE and ABM models in other fields of study — e.g., Lanchester ODE combat models vice ABM combat models.
Effect of Base Material on RFID Tag Readability
Authors: Parikh Chirant , Zeid Abe , Kamarthi Sagar
Published: July 2009

RFID tags are commonly used to track products in many applications including retail and pharmaceutical industries. Tag readability is detrimental to the successful implementation and use of RFID in commercial applications. Tag readability is adversely affected when tags are adhered to metal surfaces such as metal cans and containers. This paper studies the effect of base material on tag readability. We have designed and built an experimental setup in the RFID lab to perform our studies. Our studies show that the metal effect is influenced by the distance between the tag and the base material (padding material) and the distance between the tag and its RFID reader. The studies also reveal the threshold values for improving tag readability.
Fairness in Agent Based Simulation Frameworks
Authors: Welch Lawrence , Ekwaro-Osire Stephen
Published: July 2009

An agent based simulation engine should provide a fair playing field for all of its agents. A fundamental design axiom of agent based simulation frameworks is that the simulation engine should not arbitrarily bias its execution towards one agent or another. This fairness is basic to giving the agent modeler confidence that differences in behavior and performance between agents derive legitimately from the simulation modeling, initial conditions or specific agent characteristics, rather than the capriciousness of the underlying framework. One aspect of fairness in a simulation is the relative order of execution of agents over time. This order of execution is affected by techniques employed by frameworks to simulate the concurrent activities of multiple agents. One such technique is multi-threading. Multi-threaded operating systems, or programming languages and environments, such as Java, allow multiple agents, represented by software threads, to share the computer’s execution time by taking turns, thus appearing to act simultaneously. The precise order of execution of peer threads in multi-threaded applications is often out of the hands of the programmer, and may be determined exclusively by the operating system or program execution environment. However, if overlooked by the framework developer, the idiosyncrasies of a particular thread ordering mechanism can pass on to the modeler inherent random behavior that is neither intuitive, nor in line with the modeler’s expectations. To be considered fair, the engine should aim to provide all agents with equal probability of executing first within a time step, or last, or in any position in between. This paper analyzes the sequencing of agent thread execution within a Java framework that implements a multi-threaded, time-stepping, agent based simulation engine. The natural ordering of Java thread execution is demonstrated to be unfair (that is, not uniform) in its treatment of agents. This research shows that the standard mechanism of Java thread scheduling, while appropriate for most applications, is inappropriate on its own for the agent based framework. It is demonstrated that with Java’s standard thread scheduling algorithm, over time certain agents tend to execute ahead of others within each time step, while others tend to execute in the middle or at the back of the pack. This paper then introduces and demonstrates the “Uniform Specific Notification” pattern, a technique that produces a fairer, uniformly distributed random order for the initial execution of Java agent threads at each simulation time step.
Meta4acle: Generating Compelling Metaphors for Design
Authors: Kolb Erik M. W. , Hey Jonathan , Sebastian Hans-Ju¨rgen , Agogino Alice M.
Published: July 2009

Metaphors have successfully been used by new product development and design teams to help frame the design situation and communicate new products to stakeholders. Yet, the process of finding a compelling metaphor often turns upon stumbling upon it or a flash of insight from a team member. We present Meta4acle: a Metaphor Exploration Tool for design that suggests possible metaphors to make the process more one of ‘seeking out’ than ‘stumbling upon’ an effective metaphor. The tool takes data about the project in the form of a title, domain and key associations required of the metaphor and returns suggestions from a database of possible metaphor sources. We built a Meta4acle prototype and evaluated it with positive results for three existing design case studies. We present plans for its full implementation and evaluation.
Product Family Commonality Selection Through Interactive Visualization
Authors: Khire Ritesh , Wang Jiachuan , Bailey Trevor , Lin Yao , Simpson Timothy W.
Published: July 2009

High dimensionality and computational complexity are curses typically associated with many product family design problems. In this paper, we investigate interactive methods that combine two traditional technologies — optimization and visualization — to create new and powerful strategies to expedite high dimensional design space exploration and product family commonality selection. In particular, three different methods are compared and contrasted: (1) exhaustive search with visualization, (2) individual product optimization with visualization, and (3) product family optimization with visualization. Among these three, the individual product optimization with visualization methods appears to be the most suitable one for engineer designers, who do not have strong optimization background. This method allows designers to “shop” for the best designs iteratively, while gaining key insight into the tradeoff between commonality and individual performance. The study is conducted in the context of designing a UTC product using an in-house, system-level simulation tool. The challenges associated with (1) design space exploration involving mixed-type design variables and infeasibility, and those associated with (2) visualizing product family design spaces during commonality selection are addressed. Our findings indicate a positive impact on the company’s current approach to product family design and commonality selection.
Varying Weights in Multi-Attribute Decision Making
Authors: Qiu Yuming , Ge Ping , Junker Joseph F.
Published: July 2009

Extreme cases that contain either extremely high or pretty low preference attribute(s) are investigated for multi-attribute decision making problems. Normal cases occur most of the time, and many existing methods have been developed to support the decision making in such scenarios. Extreme cases are possible in real applications, and they are usually present intriguing scenarios because of the potential fuzzy and varying decision criteria. To capture this phenomenon, varying weights are introduced to simulate the change pattern concerning relative importance of attributes, and a uniform framework has been developed to support the decision making mathematically for extreme cases. A real application from Industrial Assessment Center at Oregon State University is used to demonstrate the proposed method, and the result shows its capability of capturing a decision maker’s flexible decision altitudes, and indicates its advantage over existing constant weight methods.
A Functional Classification Framework for the Conceptual Design of Layered Manufacturing Technologies
Authors: Williams Christopher B. , Mistree Farrokh , Rosen David W.
Published: July 2009

There exist many different layered manufacturing technologies for the realization of prototypes and fully-functional artifacts. Although extremely different in solution principle and embodiment, there exists functional commonality between each technology. This commonality affords the authors an opportunity to propose a new classification framework for layered manufacturing technologies. In addition to using it as a means of classifying existing processes, the authors present the framework as a tool to aid a designer in the conceptual design of new layered manufacturing technologies. The authors close the paper with an example of such an implementation; specifically, the conceptual design of a novel means of obtaining metal artifacts from three-dimensional printing.
A Multi-Domain Analysis Framework for Product Development
Authors: Bradley Joe A. , Yassine Ali A.
Published: July 2009

The 21st century brings many new challenges to the product development (PD) community mainly due to a drastic increase in the scale and complexity of engineered systems. This requires the collaboration of various entities and resources within and outside firm boundaries. To address these new challenges, this paper proposes a novel framework for an enterprise-wide PD information management system. The proposed framework provides an integrative view of the various dependencies and information flows that co-exist in three main PD analysis domains (i.e., people, products, and processes) and analysis methods for the discovery of gaps or ‘misalignment’ between them. These gaps could help explain why some organizations are able to provide more competitive products within a given industry. Moreover, the framework suggests that the characteristics of how an organization acquire data, interpret information, and apply knowledge will impact the final architecture of the product. Finally, we demonstrate this framework by analyzing an open source software (OSS) project, which offers some insights and new directions into how the transfer of data, information, and knowledge impacts the final (source code) architecture and design.
Aligning Shape Rule Creation With Modular Design: Minimizing the Cost of Using Shape Grammars
Authors: McCormack Jay , Cagan Jonathan , Antaki James
Published: July 2009

Shape grammars provide the means to represent the physical embodiment of a class of products in a set of generative rules. Once developed, the shape grammar can be used to generate new forms through automated synthesis or interaction by one or more designers. However, a fundamental shortcoming of this rule-based system is that creating the shape rules is time consuming and imprecise. The traditional approach to create a set of rules from an existing set of products was an ad hoc process of generalizing form, identifying feature options, and classifying logical subdivisions of the complete product geometry. This paper proposes a formal method of shape grammar creation that is aligned with well-known design methodologies and tools in order to enable the creation of a shape grammar during the product development process. The established methodologies for creating functional models and modular products provide many of the requisite steps for creating a shape grammar and provide a skeleton onto which a rule creation approach can be mapped.
Industrial Case Studies in Product Flexibility for Future Evolution: An Application and Evaluation of Design Guidelines
Authors: Tilstra Andrew H. , Backlund Peter B. , Seepersad Carolyn C. , Wood Kristin L.
Published: July 2009

A product’s flexibility for future evolution is its ability to be quickly and economically adapted to meet changing requirements. In previous work, a set of guidelines has been developed for designing flexible products. In this paper, two similar industrial case studies are presented to investigate the effectiveness of these guidelines for designing small-lot products with flexibility for future evolution. The systems are real products that have been designed and built by the authors, providing unrestricted insight into the design process and outcome of each project. The first product, a large testing system for high pressure seals, was designed without the aid of flexibility for future evolution guidelines. The second product, an automated welding test station, was designed with flexibility for future evolution as a specific deliverable of the final product. The flexibility of each system was measured by considering its adaptability to prototypical change modes. Of the two systems, the welding system was found to be more flexible than the seal testing system. The welding system also served as an example of integrating product flexibility guidelines throughout the development process.
Plane Strain Indentation of Snow at the Microscale
Authors: Lee Jonah H.
Published: July 2009

Indentation tests are commonly used to characterize terrain properties in tire-terrain interaction. By way of motivation, in order to understand and quantify the sources of uncertainty in tire-snow interaction, we present a new direction of research studying the indentation behavior of snow at the microscale. The mechanical behavior of snow is known to be influenced significantly by its microstructure which can evolve due to environmental conditions. The traction and compaction of snow due to interfacial friction and contact exerted by various parts of the tire thus should also be dependent on snow’s microstructure. Due to the geometric scales of parts of the tire, from sipes to tread blocks, tire-snow interaction is inherently a multi-scale problem ranging from microscale to macroscale. This paper addresses the microscale behavior of medium-density snow (density 387 kg / m3) whose microstructure is obtained via 3-D X-Ray Microtomography (XMT). A physically based, history and rate dependent viscoplastic model for polycrystalline ice was incorporated into a meshfree Material Point Method simulation code using an implicit algorithm on a parallel computer for the indentation of a punch on snow under the plane strain condition at a nominal strain rate of 0.0014 Sec−1. Load/pressure vs. sinkage/strain relationship was obtained and compared with macroscopic pressure-sinkage relationship. Micromechanical behavior of the indentation test was also presented and discussed.
E-CAFD: Extended-Effect Driven Computer-Aided Functional Design
Authors: Cao Guozhong , Guo Haixia , Tan Runhua
Published: July 2009

To match for complex product function and to solve insufficient computer aid for functional design, the Extended-Effect driven Function-Behavior-Structure (EE-FBS) model is constructed. A multi-flow and multi-pole effect model is presented by extending the one with single input/output flow in TRIZ. Four effect patterns and three reasoning methods are proposed to create effect chains. The FBS model is extended to an EE-FBS model based on effect through the description of the law of mapping overall function to external behavior, from external behavior to sub-behavior, etc. A functional design process was presented based on the EE-FBS model, and the computer-aided functional design software system is developed. A design example for functional design of Chinese dropping pill medicine demonstrates the proposed method is feasible.
A Method for Creative Behavioral Design Based on Analogy and Blending From Natural Things
Authors: Tsujimoto Kazuya , Miura Shinji , Tsumaya Akira , Nagai Yukari , Chakrabarti Amaresh , Taura Toshiharu
Published: July 2009

In the near future, robots and CG (computer graphics) will be required to exhibit creative behaviors that reflect designers’ abstract images and emotions. However, there are no effective methods to develop abstract images and emotions and support designers in designing creative behaviors that reflect their images and emotions. Analogy and blending are two methods known to be very effective for designing creative behaviors. The aim of this study is to propose a method for developing designers’ abstract behavioral images and emotions and giving shape to them by constructing a computer system that supports a designer in the creation of the desired behavior. This method focuses on deriving inspiration from the behavioral aspects of natural phenomena rather than simply mimicking it. We have proposed two new methods for developing abstract behavioral images and emotions by which a designer can use analogies from natural things such as animals and plants even when there is a difference in the number of joints between the natural object and the design target. The first method uses visual behavioral images, the second uses rhythmic behavioral images. We have demonstrated examples of designed behaviors to verify the effectiveness of the proposed methods.
Computational Steering of Interactive Material Flow Simulations
Authors: Lietsch Stefan , Laroque Christoph , Zabel Henning
Published: July 2009

In this paper we present the integration of computational steering techniques into the interactive material flow simulation d3FACT insight. This kind of simulation differs from traditional, long running High Performance Computing (HPC) simulations such as Computational Fluid Dynamics (CFD) or Molecular Dynamics in many aspects. One very important aspect is that these simulations run in (soft) real-time, thus the corresponding visualization needs to be updated after every step of the simulation. In turn, this allows to let changes, made through the visualization, impact the actual simulation and again, to see the effects in visualization. To allow this kind of control over the simulation and to further provide a flexible basis to integrate several instances of simulation, visualization and steering components, we used and enhanced a self-developed computational steering platform, which fits best for the needs of highly interactive and distributed simulations. Thereby we are able to realize multi-user and comparative scenarios which were not possible in this field of simulations before.
Copulas for Demand Estimation for Portfolio Reuse Design Decisions
Authors: Pandey Vijitashwa , Thurston Deborah
Published: July 2009

Design for multiple product lifecycles with component reuse potentially improves profitability, customer satisfaction and environmental impact. However, deciding on the scope and the level of detail (granularity) to be considered in the design process can be challenging. Although a comprehensive model that takes into account all important issues would be immensely useful, modeling difficulties and computational intractability prevent their successful implementation. This paper extends the scope of a previously developed design decision tool for determining optimal end-of-lifecycle decisions. The single product case is extended to a product portfolio, which has been shown to capture more demand. Demand is explicitly considered and its modeling is accomplished with the use of copulas. An important result from statistics, Sklar’s theorem, provides a way to use data from existing product sales to estimate demand for currently nonexistent reused products. In addition, effective age calculations are updated. On the computational front, time-continuation and seeding is used for NSGA-II to converge to optima more quickly in the resulting larger problem. A personal computer case study illustrates the effect of different parameters such as portfolio size, the possibility of recycle, and limits on environmental impact (as opposed to mandated take-back).
Emotional Competence in Human-Robot Communication
Authors: Esau Natascha , Kleinjohann Lisa , Kleinjohann Bernd
Published: July 2009

Since emotional competence is an important factor in human communication, it will certainly also improve communication between humans and robots or other machines. Emotional competence is defined by the aspects emotion recognition, emotion representation, emotion regulation and emotional behavior. In this paper we present how these aspects are intergrated into the architecture of the robot head MEXI. MEXI is able to recognize emotions from facial expressions and prosody of natural speech and represents its internal state made up of emotions and drives by according facial expressions, head movements and speech utterances. For its emotions and drives internal and external regulation mechanisms are realized. Furthermore, this internal state and its perceptions, including the emotions recognized at its human counterpart, are used by MEXI to control its actions. Thereby MEXI can react adequately in an emotional communication.
Layer Depth-Normal Images for Complex Geometries: Part One — Accurate Modeling and Adaptive Sampling
Authors: Chen Yong , Wang Charlie C. L.
Published: July 2009

The layered depth-normal images (LDNIs) is an implicit representation of solid models that sparsely encodes the shape boundary in three orthogonal directions. We present a LDNI-based geometric modeling method for applications with high accuracy requirements. In our method, we first construct LDNIs models from input polygonal models. The accuracy of the generated LDNIs models can be controlled by setting pixel width during the construction process. Even for very complex geometries and high accuracy requirements, the construction process is fast with the aid of graphics hardware. Based on the LDNIs models, we then perform geometric modeling operations. Two types of operations are presented including regularizing and Boolean operations. The geometric modeling operations are straightforward and easy to be implemented robustly. From the processed LDNIs model, an adaptive sampling method is presented to construct a cell representation that includes both uniform and octree cells. Finally 2-manifold polygonal mesh surfaces are constructed from the cell representation. For high accuracy requirements that are typical in CAD/CAM applications, we present a volume tiling technique and a parallel implementation to accelerate the computation. Our method achieves a good balance between the accuracy and computational resources. We report experimental results on a variety of CAD models. The results demonstrate the effectiveness and efficiency of our approach especially for modeling complex geometries.
An Approach on Tuning the Frequency of a Rotating Blade
Authors: Duong L. , Kazerounian K. , Murphy K. D.
Published: July 2009

In a gas turbine engine, the forced vibration of a turbine blade under resonant conditions is undesirable and may lead to premature high cycle fatigue failure. From the aspect of structural integrity, this demonstrates that it is extremely important to tune the excited vibration mode out of the operating speed range. This leads to the question: Is it possible to perform structural perturbations, namely to the mass and stiffness, in such a way that only the eigenvalue of choice significantly changes — while causing little or no change in the other natural frequencies? This is focus of the present paper. Due to the complexity of the blade structure, it is difficult to obtain an analytical solution from the eigenvalue perturbation theory. Nevertheless, the derived analytical expressions provide guidance from which the finite element method may successfully be applied as an alternative approach. This tuning approach is validated experimentally.
Fuzzy Control of Motion and Force for Flexible Master-Slave Systems
Authors: Hoshino Yohei , Kobayashi Yukinori , Furuta Yusuke
Published: July 2009

This is the study of the motion, vibration and contact force control of a flexible master-slave system (FMSS). In this study, the master arm is a one-link arm that consists of a rigid body and the slave arm is a one-link arm that consists of a flexible link. Bilateral control based on passivity and a type-1 optimal servo system based on a linear quadratic regulator (LQR) are applied to the system. Fuzzy control is employed to reinforce the advantages of these control methods. A state observer is employed to construct these controllers, however, the accuracy of state estimation deteriorates while the slave-arm is in contact with objects. Therefore improvements in the accuracy of the state estimation are attempted by applying the disturbance-state observer. The performance of the present method is evaluated by experimental results.
A New Test-Bench for Study of Plain Bearings Under Mixed Lubrication
Authors: Albers Albert , Beauvais S. , Bsul J. , Burger W.
Published: July 2009

The experimental knowledge about medium lubricated journal bearings (e.g. diesel-oil lubricated sliding bearings in fuel-injection systems) is far too small in order to confirm the different hypotheses of the actual simulation models. The study of such components implicates very restrictive requirements on security against explosion, exact measurement of the friction torque and so on. A new test bench design to meet these requirements is presented, allowing a system-conform study of the components. For a high resolution of the temperature repartition in the smearing gap, thin film sensors, which have allowed the verifications experiments in the field of the Elastohydrodynamic-lubrication (EHL) are being enhanced. Beside a higher wear resistance, a reduction of the sensor size is an important requirement for the new sensor generation, allowing the resolution of local phenomena in the mixed lubrication. For the electrical isolation and wear protection of the new sensors developed at the Institute of Product Development of the University of Karlsruhe (TH) (IPEK), diamond like carbon (DLC) coatings are used. For the fulfillment of the requirements on the size of the sensors, a new concept of micro thermocouples is presented.