bluuebunny/crossref_metadata_2025 huggingface dataset:
A Framework for Choice Modeling in Usage Context-Based Design
Authors: He Lin , Hoyle Christopher , Chen Wei , Wang Jiliang , Yannou Bernard
Published: March 2011

Usage Context-Based Design (UCBD) is an area of growing interest within the design community. A framework and a step-by-step procedure for implementing consumer choice modeling in UCBD are presented in this work. To implement the proposed approach, methods for common usage identification, data collection, linking performance with usage context, and choice model estimation are developed. For data collection, a method of try-it-out choice experiments is presented. This method is necessary to account for the different choices respondents make conditional on the given usage context, which allows us to examine the influence of product design, customer profile, usage context attributes, and their interactions, on the choice process. Methods of data analysis are used to understand the collected choice data, as well as to understand clusters of similar customers and similar usage contexts. The choice modeling framework, which considers the influence of usage context on both the product performance, choice set and the consumer preferences, is presented as the key element of a quantitative usage context-based design process. In this framework, product performance is modeled as a function of both the product design and the usage context. Additionally, usage context enters into an individual customer’s utility function directly to capture its influence on product preferences. The entire process is illustrated with a case study of the design of a jigsaw.
A Geometric Constructive Approach for the Workspace Analysis of Symmetrical 5-PRUR Parallel Mechanisms (3T2R)
Authors: Tale Masouleh Mehdi , Saadatzi Mohammad Hossein , Gosselin Cle´ment , Taghirad Hamid D.
Published: March 2011

This paper investigates an important kinematic property, the constant-orientation workspace, of five-degree-of-freedom parallel mechanisms generating the 3T2R motion and comprising five identical limbs of the PRUR type. The general mechanism originates from the type synthesis performed for symmetrical 5-DOF parallel mechanism. In this study, the emphasis is placed on the determination of constant-orientation workspace using geometrical interpretation of the so-called vertex space, i.e., motion generated by a limb for a given orientation, rather than relying on classical recipes, such as discretization methods. For the sake of better understanding a CAD model is also provided for the vertex space. The constructive geometric approach presented in this paper provides some insight into the architecture optimization. Moreover, this approach facilitates the computation of the evolution of the volume of the constant-orientation workspace for different orientations of the end-effector.
Design of Revolute Joints for Insert Molding: A Step Towards Realizing Low Cost Highly Articulated Robot Structures
Authors: Ananthanarayanan Arvind , Ehrlich Leicester , Desai Jaydev P. , Gupta Satyandra K.
Published: March 2011

Creating highly articulated miniature robotic structures requires assembling a large number of small parts. This is a very challenging task and increases cost of the robots. Insert molding presents the possibility of creating a highly articulated structure in a single molding step. This can be accomplished by placing multiple metallic bearings in the mold and injecting plastic on top of them. In theory, this idea can generate a multi degree of freedom robot in just one processing step without requiring any post molding assembly operations. However, the polymer material has a tendency to shrink on top of the metal bearings and hence jam the joints. Hence, until now insert molding has not been used to create articulated structures. This paper presents a theoretical model for estimating the extent of joint jamming that occurs due to the shrinkage of the polymer on top of the metal bearings. The level of joint jamming is seen as the effective torque needed to overcome the friction in the revolute joints formed by insert molding. We then use this model to select the optimum design parameters which can be used to fabricate functional robotic assemblies while meeting manufacturing constraints. Our analysis shows that the strength of weld-lines formed during the in-mold assembly process play a significant role in determining the minimum joint dimensions necessary for fabricating functional revolute joints. We have used the models and methods described in this paper to successfully fabricate the structure for a minimally invasive medical robot prototype with potential applications in neurosurgery. To the best of our knowledge this is first demonstration of building an articulated structure with multiple degrees of freedom using insert molding.
A Review of Bird-Inspired Flapping Wing Miniature Air Vehicle Designs
Authors: Gerdes John W. , Gupta Satyandra K. , Wilkerson Stephen A.
Published: March 2011

Physical and aerodynamic characteristics of the bird in flight may offer benefits over typical propeller or rotor driven miniature air vehicle (MAV) locomotion designs in certain types of scenarios. A number of research groups and companies have developed flapping wing vehicles that attempt to harness these benefits. The purpose of this paper is to report different types of flapping wing designs and compare their salient characteristics. For each category, advantages and disadvantages will be discussed. The discussion presented will be limited to miniature-sized flapping wing air vehicles, defined as 10–100 grams total weight. The discussion will be focused primarily on ornithopters which have performed at least one successful test flight. Additionally, this paper is intended to provide a representation of the field of current technology, rather than providing a comprehensive listing of all possible designs. This paper will familiarize a newcomer to the field with existing designs and their distinguishing features. By studying existing designs, future designers will be able to adopt features from other successful designs. This paper also summarizes the design challenges associated with the further advancement of the field and deploying flapping wing vehicles in practice.
Entropy-Based Heavy Tailed Distribution Transformation for Network Traffic Analysis
Authors: Han Keesook J.
Published: March 2011

In general, network traffic data has a heavy-tailed probability distribution. The Entropy-Based Heavy Tailed Distribution Transformation (EHTDT) has been developed to convert the heavy tailed network traffic data distribution into a transformed probability distribution. In practice, the entropy distribution of the transformed probability distribution exhibits a type of linearity that gives rise to an eigenstructure that allows the characterization of network traffic data to effectively lossily compress network traffic data via the Rate Controlled Eigen-Based Coding. The aforementioned eigenstructure is motivated by singular value decomposition theory. A very high compression ratio can be achieved by the proposed method. Results of applying the methods to real network traffic data network traffic data are presented.
Reconfigurable Products and Their Means of Reconfiguration
Authors: Haldaman Jillian , Parkinson Matthew B.
Published: March 2011

Reconfigurable systems are able to meet the increasingly diverse needs of consumers. A reconfigurable system is able to change its configuration repeatedly and reversibly to match the customer’s needs or the surrounding environment, allowing the system to meet multiple requirements. In this paper, a sample of reconfigurable products was studied to better understand the methods used to achieve different configurations. Four methods of reconfiguration were discovered. This expands work previously done in a parallel field with products that transform where only three methods were identified. In order to support the findings of this paper, the variations were identified and example products were presented that clearly show the need for at least one additional method of reconfiguring. A case study is also provided to illustrate the benefits of incorporating four principles, as apposed to three, into the concept generation phase of new reconfigurable product development.
Design Requirements for a Tendon Rehabilitation Robot: Results From a Survey of Engineers and Health Professionals
Authors: Patoglu Volkan , Ertek Gurdal , Oz Ozgur , Zoroglu Deniz , Kremer Gul
Published: March 2011

Exoskeleton type finger rehabilitation robots are helpful in assisting the treatment of tendon injuries. A survey has been carried out with engineers and health professionals to further develop an existing finger exoskeleton prototype. The goal of the study is to better understand the relative importance of several design criteria through the analysis of survey results and to improve the finger exoskeleton accordingly. The survey questions with strong correlations are identified and the preferences of the two respondent groups are statistically compared. The results of the statistical analysis are interpreted and insights obtained are used to guide the design process. The answers to the qualitative questions are also discussed together with their design implications. Finally, Quality Function Deployment (QFD) has been employed for visualizing these functional requirements in relation to the customer requirements.
Identifying Potential Applications for Lamina Emergent Mechanisms Using Technology Push Product Development
Authors: Albrechtsen Nathan B. , Magleby Spencer P. , Howell Larry L.
Published: March 2011

The maturation of lamina emergent mechanism (LEM) technology allows for incorporation into new products. LEMs are defined by three basic, functional characteristics: they (1) are compliant; (2) are fabricated from planar materials; and (3) emerge from a flat initial state. The associated advantages, design challenges, and design tools of each of these characteristics are described. A discussion of opportunities for LEMs that are enabled by the advantages of the functional characteristics is also included. Technology push product development processes were employed in a LEM workshop where seventeen industry professionals helped identify over 200 potential applications for the technology. The most promising ideas are described for disposable LEMs, novel arrays of LEMs, scaled LEMs, LEMs with surprising motion, shock absorbing LEMs, and deployable LEMs.
Modeling Electrostatic Actuator Pull in Behavior With Proper Orthogonal Decomposition
Authors: Binion David , Chen Xiaolin
Published: March 2011

Electrostatic operation has become one of the most common actuation/sensing techniques due to its ease of integration in complex micro-electro-mechanical-systems (MEMS). A critical issue with electrostatic operation is the avoidance of pull in phenomenon. While analytical solutions based on lumped model assumptions are available, finite element method (FEM) has increasingly been used to study pull in phenomenon of intricate devices. Geometrically complex designs require large discretized FEM models to obtain accurate simulations resulting in MEMS designers continually reaching FEM limits due to excessive demands on CPU-time and memory resources. Proper orthogonal decomposition (POD) has been investigated to improve computational efficiency by generating reduced models that capture the pull in characteristics of an electrostatic device. An FEM model of an electrostatically actuated micro resonator beam structure was produced. Employing POD, a basis function was generated that characterized the pull in behavior of the full scale model. The basis function was used to assemble a reduced model. Pull in analysis was performed with the reduced and full FEM models for comparison. It was found that the reduced model achieved similar results as compared to the full model while the computational time was drastically reduced.
Tools to Assist Teaching and Learning of Mechanisms, Robotics, and Biomechanics
Authors: Williams Robert L.
Published: March 2011

This paper details some innovations developed at Ohio University for augmenting the teaching and learning of mechanism kinematics and dynamics, robot kinematics, dynamics, and control, and the musculoskeletal biomechanics of human motion. Common to all three courses are NotesBooks, significant MATLAB use in class, homework, and projects, term projects simulated from real-world applications, and Internet resources developed and hosted by the author at Ohio University.
Design of Sinusoidal Auxetic Structures for High Shear Flexure
Authors: Shankar Prabhu , Ju Jaehyung , Summers Joshua D. , Ziegert John C.
Published: March 2011

This paper presents the analytical model to predict the effective in-plane shear modulus G12* for auxetic honeycomb mesostructure with sinusoidal re-entrant wall. Also, a comparative study is conducted on the ability of the sinusoidal mesostructure over auxetic mesostructure for high shear flexure. In an effort to design components with high shear flexure, the re-entrant wall of the auxetic honeycomb is replaced with a sinusoidal wall. Existing analytical models that predict the effective in-plane elastic properties for auxetic honeycomb mesostructure are limited to straight re-entrant wall. In order to predict the effective in plane shear modulus, G12*, for conceptual design study, an analytical model is needed. The principle of energy methods is used to determine the effective in-plane shear modulus and is verified with the solution in ABAQUS. The analytical model is in agreement with the computational model with a 10% maximum error over a wide range of cell wall thickness and shear strain. The two structures are designed to possess the same equivalent shear modulus and the degree of shear flexure is measured computationally in terms of yield shear strain. The sinusoidal structure introduces nonlinearity with increase in cell wall thickness and shear strain. This nonlinearity causes the sinusoidal auxetic mesostructure to have low shear flexure at a high shear modulus which is higher than about 10MPa. However, it is marginally better than auxetic mesostructure at a low shear modulus which is 10MPa and less.
Experimental Damage Characterization of Hexagonal Honeycombs Subjected to In-Plane Shear Loading
Authors: Joshi Shraddha , Ju Jaehyung , Berglind Luke , Rusly Roy , Summers Joshua D. , DesJardins John D.
Published: March 2011

Experimental study on the damage of hexagonal honeycombs under in–plane shear loading does not appear to be available in the literature. In this paper, shear damage behaviors of five different hexagonal mesostructures are investigated with rapid prototyped polycarbonate (PC) honeycomb coupon samples and proper design of a fixture for shear loading. Effective shear stress-strain curves of PC honeycomb coupons are generated for each shear test and the corresponding local cell wall failure is investigated. Two different failure modes of PC honeycombs were observed primarily depending on the cell wall thickness: The PC honeycombs having a lower cell wall thickness induce the plastic post buckling, resulting in preventing propagation of initial cracks through the cell wall end up with higher plastic load bearing. On the other hand, the failure mode of the honeycombs having a high cell wall thickness is the cell wall fracture by crack propagation through wall without severe buckling.
Optimal Adaptable Design Considering Changes of Requirements, Configurations and Parameters in the Whole Product Life-Cycle
Authors: Xue D. , Hua G. , Mehrad V. , Gu P.
Published: March 2011

Adaptable design is a new design approach to create an adaptable product to replace multiple products for satisfying the different requirements in the product life-cycle. In this research, a method to identify the optimal product considering changes of requirements, configurations and parameters in the whole product life-cycle is introduced. The requirements, configurations and parameters of the adaptable product are modeled as functions of the life-cycle time parameter. The adaptable product is changed to different configurations and parameters to satisfy the different requirements in different life-cycle time periods. The evaluation measures, which are achieved from configurations and parameters, are also changed in different life-cycle time periods. The optimal product, modeled by its configurations and parameters, considering the whole product life-cycle is identified through optimization. A case study is provided to demonstrate how the introduced method can be employed for solving engineering problems.
Skyhook Control of a Mixed Mode Magnetorheological Fluid Mount
Authors: Wang Shuo , Nguyen The , Anderson Walter , Ciocanel Constantin , Elahinia Mohammad
Published: March 2011

Magnetorheological (MR) fluid mounts have their own advantages over the hydraulic mounts because they can provide extra damping and stiffness due to the MR effect. Many papers contribute to the control of MR fluid dampers, while very few papers focus on the control of MR mounts. This paper investigated skyhook control for a mixed mode MR fluid mount. The MR fluid mount can operate in two working modes: flow mode and squeeze mode. The skyhook control algorithms were developed and studied for the flow mode and squeeze mode separately and simultaneously. Simulation results show that the skyhook control can significantly reduce the resonance peak and achieve the lowest transmissibility in the whole working frequency range of the mount. When flow mode and squeeze mode are activated and controlled at the same time, the effect of squeeze mode is more obvious than that of the flow mode.
Complexity Metrics for Directional Node-Link System Representations: Theory and Applications
Authors: Mathieson James L. , Summers Joshua D.
Published: March 2011

This paper presents an approach to defining and quantifying the complexity of systems as represented in mixed (directed and non-directed) bipartite graphs through the presentation of a central example as well as other applications. The approach presented defines nine measurements of different properties of the graph system. These measurements are derived from the representation of the system into a three dimension relational design structure matrix as well as the projections and transformations of this matrix. The metrics generated address dimensional and connective size, shortest path properties, and the decomposability of the system. Finally, a normalization and aggregate approach of these metrics is then given. This aggregation is visualized with spider graphs that facilitate viewing multiple aspects of complexity within a single perspective.
Requirement Change Propagation Prediction Approach: Results From an Industry Case Study
Authors: Morkos Beshoy , Summers Joshua D.
Published: March 2011

This paper presents an industry case study investigating change propagation due to requirement changes. This paper makes use of a change propagation prediction tool, ΔDSM, to identify if the propagated changes could have been identified and predicted. The study used an automation firm’s client project as the study subject. The project entailed 160 requirements, changing over the span of 15 month. Engineering change notifications were developed for each change and documented under the firm’s data management system. This study makes use of the change notifications to identify if any of the change were as a result of a previous change. The findings of this paper indicated the changes that occurred could have been predicted as the ΔDSM was able to predict affected requirements. This was identified by finding subsequent requirements in the engineering change notification documentation that the ΔDSM indicated might change.
Model-Based Method to Translate System Level Customer Need to Part Specification
Authors: Van Eikema Hommes Qi D.
Published: March 2011

Products are successful because they meet customer needs. However, many customer needs are not expressed in measurable terms. In addition, when such needs are achieved by a complex system made of hardware parts and software, decomposing customer needs to part-level specification is not a trivial task. This paper presents a model-based approach to address such problems. In the case study, the customer need was the noise and vibration level of an unconventional gasoline engine system when running at idle. The hardware component whose performance tolerance needed to be specified was a new type of fuel injectors. These new fuel injectors had higher piece-to-piece performance variations than the conventional fuel injectors. It was unclear whether such variation was acceptable for customer perceived powertrain quality. A virtual powertrain system simulation model was used to analytically evaluate the impact of the fuel injector performance variability. Monte Carlo simulation was carried out to assess the impact of injector variability. The results from the simulation were further refined using engine hardware testing. This study made recommendations for the acceptable level of hardware tolerance, which was different from what the supplier of the injectors had suggested.
Validating the Generational Variety Index (GVI) Through Product Family Optimization: A Preliminary Study
Authors: Bobuk Aaron , Slingerland Laura A. , Simpson Timothy W. , Donaldson Ben , Reichard Karl
Published: March 2011

Effective product platforms must strike an optimal balance between commonality and variety. Increasing commonality can reduce costs by improving economies of scale while increasing variety can improve market performance, or in our robot family example, satisfy various robot missions. Two metrics that have been developed to help resolve this tradeoff are the Generational Variety Index (GVI) and the Product Family Penalty Function (PFPF). GVI provides a metric to measure the amount of product redesign that is required for subsequent product offerings, whereas PFPF measures the dissimilarity or lack of commonality between design (input) parameters during product family optimization. GVI is examined because it is the most widely used metric applicable during conceptual development to determine platform components. PFPF is used to validate GVI because of its ease of implement for parametric variety, as used in this case. This paper describes a product family trade study that has been performed using GVI for a robot product family and compares the results to those obtained by optimizing the same family using PFPF. This work provides a first attempt to validate the output of GVI by using a complementary set of results obtained from optimization. The results of this study indicate that while there are sometimes similarities between the results of GVI and optimization using PFPF, there is not necessarily a direct correlation between these two metrics. Moreover, the platform recommended by GVI is not necessarily the most performance-optimized platform, but it can help improve commonality. In the same regard, PFPF may miss certain opportunities for commonality. The benefits of integrating the two approaches are also discussed.
A Grammatical Approach for Customization of Laminated Composite Materials
Authors: Nandi Soumitra , Siddique Zahed , Altan M. Cengiz
Published: March 2011

The wide range of properties covered by the manufacturable fiber-matrix combinations of composite materials, along with their directional property characteristics, provides designers with material selection flexibility during designing composite material products. Meeting multiple property goals, however, complicates the design process as both the composite material selection and the component shape formation become complicated because the loading conditions and matrix calculations are needed to determine theoretical value of composite material properties. This paper presents a grammatical approach to simultaneously consider the shape and selection composite materials for a load-bearing component. Selection of composites involve determining the fiber and matrix, their volume fraction, and number of layers in different location of the component. A hip-replacement joint is designed using composite material to illustrate the approach.
Sampling-Based Stochastic Sensitivity Analysis Using Score Functions for RBDO Problems With Correlated Random Variables
Authors: Lee Ikjin , Choi Kyung K. , Noh Yoojeong , Zhao Liang , Gorsich David
Published: March 2011

This study presents a methodology for computing stochastic sensitivities with respect to the design variables, which are the mean values of the input correlated random variables. Assuming that an accurate surrogate model is available, the proposed method calculates the component reliability, system reliability, or statistical moments and their sensitivities by applying Monte Carlo simulation (MCS) to the accurate surrogate model. Since the surrogate model is used, the computational cost for the stochastic sensitivity analysis is negligible. The copula is used to model the joint distribution of the correlated input random variables, and the score function is used to derive the stochastic sensitivities of reliability or statistical moments for the correlated random variables. An important merit of the proposed method is that it does not require the gradients of performance functions, which are known to be erroneous when obtained from the surrogate model, or the transformation from X-space to U-space for reliability analysis. Since no transformation is required and the reliability or statistical moment is calculated in X-space, there is no approximation or restriction in calculating the sensitivities of the reliability or statistical moment. Numerical results indicate that the proposed method can estimate the sensitivities of the reliability or statistical moments very accurately, even when the input random variables are correlated.
Learning Casting Through Interactively Creating a Scenario
Authors: Siddique Zahed , Saha Mrinal C. , Barua Bipul , Akasheh Firas
Published: March 2011

Students can learn more effectively when actively involved in the learning process. Traditional approach is mainly “teacher-centered” and lacks in nurturing the students’ skills in today’s changing world. Various non-traditional approaches, that are based on experiential learning, such as project-based, problem-based or case studies-based learning have been developed and found to improve student’s learning concepts in engineering. Course modules that engage students can (i) stimulate active learning, (ii) prepare students to solve open-ended real-world problems in industries, and (iii) serve as a natural link to subsequent courses in the STEM disciplines. In this paper, we discuss Create your Scenario Interactively (CSI), which is being developed using Experiential Learning as a model to provide an engaging learning experience of engineering concepts by allowing students to visualize and interact with 2D/3D objects. A casting CSI module is being developed for a sophomore level manufacturing engineering course. We will discuss some initial research results on the CSI module development, implementation and evaluation plan for teaching manufacturing engineering course at University of Oklahoma and Tuskegee University. The pedagogical effectiveness of the CSI system will be evaluated by covering two different areas — (i) students’ learning and (ii) usability of the CSI system.
Gaming and Interactive Visualization Education Module to Help Understand Geometric Tolerancing
Authors: Siddique Zahed , Ling Chen , Saengsuri Piyamas , Chowdhury Sagar , Xu Yunjun , Geng Xiaojun
Published: March 2011

In engineering disciplines, visualization can provide an essential mode to facilitate student understanding of important and abstract concepts. Learning through a medium that combines course materials with game characteristics can be a powerful tool for education. This approach is expected to improve student willingness to learn, which will in turn increase the interests of high school and undergraduate students towards engineering as a future career. In this paper, three teaching modules based on the Gaming and Interactive Visualization for Education (GIVE) in three universities will be described in detail with enhanced game characteristics. Also, using the newly developed assessment tools, the evaluation data from the students who have experienced the GIVE system will be analyzed. More specifically, the three modules are designed and illustrated in this paper for the Flight Mechanics, Introduction to Electrical Engineering, and Design and Manufacturing. The following game characteristics have been considered and implemented in the modules: progressively balanced goal, feedback, time sensitive scoring, adaptive scoring, meaningful visual presentation, emotional involvement, avoiding guess, constitutive rule, operational rule, background, challenges, and rewards. Along with the course module development and implementation, the outcomes have been assessed using our evaluation system. The results have been analyzed and suggestions have been given for future work.
Reliability-Based Design Optimization With Confidence Level for Non-Gaussian Distributions Using Bootstrap Method
Authors: Noh Yoojeong , Choi Kyung K. , Lee Ikjin , Gorsich David
Published: March 2011

For reliability-based design optimization (RBDO), generating an input statistical model with confidence level has been recently proposed to offset the inaccurate estimation of the input statistical model with Gaussian distributions. For this, the confidence intervals of mean and standard deviation are calculated using the Gaussian distributions of input random variables. However, if the input random variables are non-Gaussian, the use of the Gaussian distributions of input variables will provide inaccurate confidence intervals, and thus, yield undesirable confidence level of the reliability-based optimum design meeting the target reliability βt. In this paper, the RBDO method using the bootstrap method, which does not use the Gaussian distributions of input variables to calculate the confidence intervals of mean and standard deviation, are proposed to obtain the desirable confidence level of output performance for non-Gaussian distributions.
Protocol-Based Multi-Agent Systems: Examining the Effect of Diversity, Dynamism, and Cooperation in Heuristic Optimization Approaches
Authors: Hanna Lindsay , Cagan Jonathan
Published: March 2011

Many heuristic optimization approaches have been developed to combat the ever-increasing complexity of engineering problems. In general, these approaches can be classified based on the diversity of the search strategies used, the amount of change to those search strategies during the optimization process, and the level of cooperation between the strategies. A review of the literature indicates that approaches which are simultaneously very diverse, highly dynamic, and cooperative are rare but have immense potential for finding high quality final solutions. In this work, a taxonomy of heuristic optimization approaches is introduced and used to motivate a new approach, entitled Protocol-based Multi-Agent Systems. This approach is found to produce final solutions of much higher quality when its implementation includes the use of multiple search protocols, the adaptation of those protocols during the optimization, and the cooperation between the protocols than when these characteristics are absent.
Pedagogy of Science in Engineering
Authors: Fauvel O. R. , Eggermont M. , McDonald C. , Caswell D. J. , Johnston C. R.
Published: March 2011

Definitions of the engineering profession include “…application of scientific principles to design or develop machines, processes, works, etc.” Significant science-based content is therefore a feature of accredited engineering curricula — a feature tending to dominate the early years thereby establishing a particular learning environment. This paper 1) identifies how a dysfunctional relationship between learning of science and the practice of engineering can arise; and 2) presents ways to improve learning of both science and design through integrated science learning. Over the course of almost three decades of trying to improve engineering design learning at the University of Calgary — employing many of the approaches described at length in the engineering education literature — it became apparent that realization of our teaching goals (e.g. quality, innovation, agility, and establishing a basis for life-long learning) might require a fundamental change in the culture of learning. Through a process of re-design plus continuous improvement, the authors have sought to develop a learning environment that establishes a learning culture that can foster the desired attributes. A pivotal aspect of this learning environment lies in the integration of science and design learning at the most fundamental level. Observation of thousands of students working on hundreds of design projects has revealed that desired outcomes can be achieved (Fig. 1).
Modeling of Air-Powered Engine Based on Time Coordinate and Optimal Approach of Gas Distribution Parameters
Authors: Chen Shian , He Ren , Lu Senlin , Yao Ming
Published: March 2011

The objective of this research is to provide systematic investigations to modeling and optimal design of the air-powered engine for improving its comprehensive performance. A thermo-dynamics model of the air-powered engine based on time coordinate is established. The simulation and analysis results show that the gas distribution parameters are the key factors to get a valid performance for the air-powered engine, such as a large valve overlap angle leading to a low efficiency of the air-powered engine in particular. A performance evaluating function of the air-powered engine considering power output and energy conversion efficiency is proposed. To improve the searching efficiency in optimization, four gas distribution parameters associated with the comprehensive performance of the air-powered engine including the intake advance angle, basal of intake sustain angle, exhaust advance angle and exhaust delay angle, are divided as a mainstream factor group and a subordinate factor group according to their relative importance. So the iterative search in optimization becomes more efficient. An example is illustrated to show the validity of the modeling. The optimal simulation result shows that we can get a bigger power output with 19.7% more than the original state and bigger energy conversion efficiency with 98.47% more than original state.
On MEMS/NEMS Biosensor Sensitivity Near Half Natural Frequency
Authors: Caruntu Dumitru I. , Knecht Martin
Published: March 2011

This paper deals with sensitivity of electrostatically actuated Bio-MEMS/NEMS resonator sensors near half natural frequency for mass detection for applications in medicine and biology. Electrostatic force along with fringe correction and Casimir effect are included in the model. They introduce parametric nonlinear terms in the system. The partial-differential equation of motion of the system is solved by using the method of multiple scales. A direct approach of the problem is then used. Two approximation problems resulting from the direct approach are solved. The phase-amplitude relationship is obtained. Numerical results for uniform electrostatically actuated micro resonator sensors are provided. An additional mass consisting of a film with a thickness of 100 nm (virus size), and a density of 0.43 of the density of the microsensor, has been added to the sensor. The additional mass shifted the amplitude-frequency curve of the sensor to lower frequencies.
Users’ Tactile Interactions With New Product Materials: An Analysis of Depth Impressions Based on Associative Concept Networks
Authors: Nagai Yukari , Georgiev Georgi V. , Taura Toshiharu
Published: March 2011

Depth impressions are an inward associative layer of the expressed impressions of humans. To analyze tactile interaction, it is essential to examine what users feel and imagine and how they create depth impressions by touching and looking at different materials. On the basis of tactile interactions, this study captures and analyzes users’ depth impressions on materials. We propose impressionable new tactile material for design from the viewpoint of depth impressions and emotional engineering. We employed a concept networks-based method to analyze the experimentally obtained verbalized protocols and to identify the depth impressions. We found that the feel of materials’ tactile naturalness is related to the depth impressions and concept networks’ complexity. The depth impressions and concept network of the proposed micro-print material are distinct and beyond that of existing natural or artificial materials. These findings will help in employing new analysis tools and developing better tactile materials for designing products.
Response Near Twice the Natural Frequency of Electrostatically Actuated Microresonators
Authors: Knecht Martin , Caruntu Dumitru I.
Published: March 2011

This paper deals with electrostatically actuated micro resonators response near twice natural frequency. Both the electrostatic force (including fringe effect) and the Casimir force are included in the model. They introduce parametric nonlinear terms in the system. The partial-differential equation of motion of the system is solved by using the method of multiple scales. A direct approach of the problem is then used. Two approximation problems resulting from the direct approach are solved. The phase-amplitude relationship is obtained. Numerical results for uniform electrostatically actuated micro resonator sensors are provided.
Consistency Checking of Mechatronic Design Models
Authors: Hehenberger Peter , Egyed Alexander , Zeman Klaus
Published: March 2011

During all phases of the design process there is a need to build models. Hierarchical models are very important tools for complex activities such as engineering design. In engineering of high performance products, mathematical modeling and simulation, i.e. experimenting with computer-based models, is an increasingly important technique for solving problems, evaluating solutions and making decisions. However, large design models may contain thousands of model elements. Designers easily get overwhelmed maintaining the correctness of such design models over time. Not only is it hard to detect new errors when the model changes but it is also hard to keep track of known errors. In the software engineering community this problem is known as a consistency problem and errors in models are known as inconsistencies. This paper presents an approach for consistency checking of mechatronic design models.
Collision-Free Locating of Mobile Cranes in 3D Lifting System
Authors: Wang Xin , Liu Jiangchuan , Liu Fang , Gao Shunde
Published: March 2011

Locating cranes is critical toward safely lifting in construction industry. In this paper, based on overlapping work envelopes, we present optimized solutions for collision-free locating of mobile cranes. Our solution first determines the feasible location areas of the cranes, which are discretized with regular grids. We then incorporate a collision detection method, through which the locations with potential collision are eliminated. With the objective of minimizing the weight sum about safety, a smart search is further performed to identify the most suitable locations. Our solution has been implemented in the intelligent computation module for 3D lifting system developed by our group. Its feasibility and effectiveness has also been demonstrated through a concrete case study.
Service Flow Simulation Using Scene Transition Nets (STN) Including Satisfaction-Attribute Value Functions
Authors: Tateyama Takeshi , Mikoshiba Satoshi , Shimomura Yoshiki , Kawata Seiichi
Published: March 2011

A new academic field, “service engineering” has emerged; it involves active investigation for increasing the productivities of service industries. However, there are only a few effective tools for the simulation and evaluation of complex services that have been designed using concepts from the field of service engineering. To overcome this shortcoming, the authors propose a multi-agent service flow simulation method using scene transition nets (STNs) that is a very useful graphical modeling and simulation method for application to discrete-continuous hybrid systems. This method treats services as complicated multi-agent and hybrid systems similar to manufacturing systems. To obtain realistic values of customer satisfaction, the authors input satisfaction-attribute value (S-AV) functions, which are often used in service engineering in service flow models using STN. This method visualizes discrete flows of services and temporal changes in the values of customer satisfaction and various other variables of service models. The authors present the results of the simulation of an online DVD rental service involving multiple agents to show the effectiveness of the proposed method that uses an STN GUI simulator developed by them.
Torsional Sensitivity and Resonant Frequency of an AFM With Parallel Sidewall Probes
Authors: Ahmadian M. T. , Kahrobaiyan M. H. , Haghighi P. , Yousefi A.
Published: March 2011

The resonant frequencies and torsional sensitivities of an atomic force microscope (AFM) assembled cantilever probe which comprises a horizontal cantilever, two vertical extensions and two tips located at their free ends are studied. This probe makes the AFM capable of measuring, for instance, the outer/inner diameter, roundness and roughness of microstructures like micro-holes and micro nozzles which leads to a time-saving swift scanning process. In this work, the effects of the sample surface contact stiffness and the geometrical parameters such as the ratio of the vertical extension length to the horizontal cantilever length and the distance of the first vertical extension from the clamped end of the horizontal cantilever on torsional resonant frequencies and sensitivities are assessed. These geometrical effects are illustrated in some figures. The results show that the low-order vibration modes are more sensitive for low values of the contact stiffness but this situation is not valid for high values.
Tool-Based Approach for the Develepment of Self-Optimizing Systems With Solution Patterns
Authors: Dumitrescu Roman , Gausemeier Ju¨rgen , Kahl Sascha
Published: March 2011

Machines are omnipresent. They produce, they transport. Machines facilitate work and assist. The increasing penetration of mechanical engineering by information technology enables considerable benefits. This circumstance is expressed by the term mechatronics, which means the close interaction of mechanics, electronics, control engineering and software engineering to improve the behavior of a technical system. The progressive integration of information technology will enable mechatronic systems with partial intelligence. We refer to such systems as self-optimizing systems. Self-optimizing systems have the ability to react autonomously and flexibly on changing operation conditions. The design of such systems is an even more interdisciplinary task than the design of conventional mechatronic systems. Additionally to mechanical, electrical, control and software engineers also experts from mathematical optimization and artificial intelligence are involved. As a consequence a domain-spanning methodology is necessary in order to guarantee an effective work flow between the participating developers from various domains and their domain-specific methods, terminologies and solutions. This contribution presents such a methodology. The main focus, however, lies on harnessing of experimental knowledge for the development of self-optimizing systems. This includes the generation and storage of once proven design solutions as well as a tool for the effective and domain-spanning reuse.
An Investigation on the Torsional Sensitivity and Resonant Frequency of an AFM With Sidewall and Top-Surface Probes
Authors: Kahrobaiyan M. H. , Ahmadian M. T. , Haghighi P. , Haghighi A.
Published: March 2011

The resonant frequencies and torsional sensitivities of an atomic force microscope (AFM) with assembled cantilever probe (ACP) are studied. This ACP comprises a horizontal cantilever, a vertical extension and two tips located at the free ends of the cantilever and the extension which makes the AFM capable of simultaneous topography at top-surface and sidewalls of microstructures especially microgears which consequently leads to a time-saving swift scanning process. In this work, the effects of the sample surface contact stiffness and the geometrical parameters such as the ratio of the vertical extension length to the horizontal cantilever length and the distance of the vertical extension from clamped end of the horizontal cantilever on torsional resonant frequencies and sensitivities are assessed. These geometrical effects are illustrated in some figures. The results show that the low-order vibration modes are more sensitive for low values of the contact stiffness but the situation is reversed for high values.
Multi Domain Design: Integration and Reuse
Authors: Woestenenk Krijn , Tragter Hans , Bonnema G. Maarten , Alvarez Cabrera Andre´s A. , Tomiyama Tetsuo
Published: March 2011

Design of mechatronic systems is becoming increasingly complex. Companies must continuously reduce time-to-market while increasing the quality, diversity, and functionality of their products. As a result, more and more specialists from various domains are needed to develop such products. To reduce time-to-market, many companies look to reducing the time it takes to design a product. Many focus on the reuse of design objects, leading to libraries of templates and standard components to speed up their design process. However, these reusable design objects are developed and maintained in the specialists’ domains, resulting in communication and integration issues between these domains. This paper discusses these issues and proposes a combined approach for model reuse, design integration, and communication between the designers, design tools, and models involved. A case study at a multi-national company successfully demonstrated that the approach leads to a faster and more consistent design process.
Design and Research for a Cost-Oriented Hybrid Electric Vehicle Architecture
Authors: Zhang Jianlong , Wang Lei , Yin Chengliang
Published: March 2011

Commercialization and popularization for HEVs are highly depended on the vehicle price and performance attributes. A novel hybrid electric vehicle architecture is designed and researched for HEV cost reduction while maintaining HEV’s potential to improve the fuel economy and drivability. In this architecture, an All-In-One-Controller (AIOC) is designed, low-cost powertrain components are selected, and a Hybrid Energy Storage System (HESS) using supercapacitor and battery concept is implemented. Cost validation and performance simulation are finished, and the results show that HEV cost can be reduced significantly and desired performance can be achieved.
Singular-Value Decomposition Based Kinematic Analysis of the Metamorphic Multifingered Hand
Authors: Cui Lei , Dai Jian S.
Published: March 2011

This paper investigates kinematics of the metamorphic multifingered robotic hand based on screw system analysis and singular value decomposition. The paper integrates the singular value decomposition with screw system and generates the reciprocity-based Jacobian matrices of a multifingered hand. This leads to the geometric constraint equation of the articulated palm as the typical feature of this robotic hand and to the kinematics characteristics equation of the hand. Symbolic singular values of the sub-matrices are derived and applied to obtaining analytical solution to inverse kinematics. The singular value decomposition helps identifying finger displacement and velocity with effect from the articulated palm and extra degrees of freedom are examined with the singular value analysis to avoid the singularities.