bluuebunny/crossref_metadata_2025 huggingface dataset:
Subfunctions as Parts of Functions: Some Formal Problems
Authors: Vermaas Pieter E.
Published: March 2011

In this paper a proof is presented that shows that the relation between technical functions and their subfunctions in functional descriptions of products can formally not be taken as a relation of parthood. Technical functions of two specific classes are modelled as well as their composition. In this modelling functions are taken as transformations of tokens of flows of energy, material and signals, which makes them proper instances of functions on many engineering accounts of functions. Then it is proved that the relations between the considered functions and their subfunctions do not in general meet the basic postulates of mereology, the theory of parthood relations. The ramification of this proof is that in engineering ontologies the relation between subfunctions and functions should not be described as a formal parthood relation.
Correlation Analysis of Oil Temperature Trend for Wind Turbine Gearbox
Authors: An Xueli , Jiang Dongxiang , Liu Shuangquan , Zhao Minghao , Liu Chao
Published: March 2011

Applying spatial correlation filtering method to de-noise the noise of wind turbine running parameters, the stochastic volatility is eliminated. On this basis, the correlation analysis between gearbox oil temperature trend and four parameters include rotor average speed, rotor temperature, gearbox driving side bearing temperature, outside air temperature is performed. The results indicate that the correlation between gearbox oil temperature trend and rotor temperature is the highest, with gearbox driving side bearing temperature takes second place, with rotor average speed takes third place but is still large. The relationship between gearbox oil temperature trend and outside air temperature is poor.
Development of Planar Mechanism State Matrices for Reconfigurable Mechanisms
Authors: Slaboch Brian J. , Voglewede Philip A.
Published: March 2011

This paper introduces mechanism state matrices as a novel way to represent the topological characteristics of planar reconfigurable mechanisms. As part of this new concept, these matrices will be used as an analysis tool to automatically determine the degrees of freedom (DOF) of planar mechanisms that only contain one DOF joints. The DOF at each state can be combined with a mechanism state matrix to form an augmented mechanism state matrix. A series of examples will be used to illustrate the proposed concept.
Interaction-Based Design Understanding for Emotional Design Review
Authors: Ito Teruaki
Published: March 2011

Due to the diversifying customer needs, emotional qualities are becoming critical factors in product development as well as the functional requirements which are still on the first priority. In addition to that, customers are becoming more involved in product development because of the trend which requires customer-centered design. To support the customer design, various tools are proposed including the design review by the customer using emerging technologies such as virtual reality. However, those tools require special devices and environments, which are not always available for general customers. This paper focuses on the design understanding aspects for emotional design review, which could be performed by general users of products as well as designers. The idea is to understand the physical shape of a product by way of interaction with its virtual model, which are normally hard to recognize just by looking at conventional display images. First, this paper describes research backgrounds to clarify the issues of reviewing emotional design. Then this paper proposes an idea of interaction-based design understanding, which could be used to support emotional design reviews conducted by general users of products. Providing some examples using a prototype system based on the idea, this paper describes how to implement the idea. This paper also presents some other application of this idea using a dental application. Finally, the paper discusses the feasibility of the idea and gives some concluding remarks with future direction of this study.
Nonlinear Forced Oscillations and Stability Analysis of the Automotive Gearbox System
Authors: Moradi Hamed , Salarieh Hasan
Published: March 2011

In this paper, nonlinear oscillation of the automobile gear system is studied. The backlash dynamic parameter is included in the nonlinear mathematical modeling of the problem. Using multiple scale method, forced vibration responses of the gear system including Primary, Sub-harmonic and Super-harmonic resonances are investigated. In each case, the jump phenomenon and stability analysis are studied. In addition, the effect of dynamic and manufacturing parameters of the gear system on the time responses are analyzed. Simulation and nonlinear analysis of the problem are developed in MAPLE and MATLAB environments.
Support Vector Regression Modeling for Design and Analysis of Mechanical Snubbing
Authors: Kaul Sudhir
Published: March 2011

This paper discusses the application of Support Vector Regression (SVR) for modeling the non-linear and hysteretic behavior exhibited by mechanical snubbing systems. Though the discussion in this paper is limited to the application of SVR to snubbing in elastomeric isolators, the approach is generic and can be applied to other dynamic systems or to systems exhibiting hysteretic behavior. A theoretical model that represents the coupled dynamics of an isolation system with the corresponding snubbing system for a single degree-of-freedom system is proposed. The theoretical model is experimentally validated and is subsequently used to build a metamodel using SVR. The results of the metamodel are compared to the theoretical model for a simulation example and are found to be comparable, thereby reducing the computational time for the design and analysis of the snubbing system by orders of magnitude. The SVR based metamodel can, therefore, be used to substitute the computationally intense theoretical model for performing design iterations and design optimization of the snubbing system, significantly reducing model complexity as well as computational time during the design cycle.
Forward Displacement Analysis of a Linearly Actuated Quadratic Spherical Parallel Manipulator
Authors: Kong Xianwen , Gosselin Cle´ment , Ritchie James M.
Published: March 2011

A quadratic parallel manipulator refers to a parallel manipulator with a quadratic characteristic polynomial. This paper revisits the forward displacement analysis (FDA) of a linearly actuated quadratic spherical parallel manipulator. An alternative formulation of the kinematic equations of the quadratic spherical parallel manipulator is proposed. The singularity analysis of the quadratic spherical parallel manipulator is then dealt with. A new type of singularity of parallel manipulators — leg actuation singularity — is identified. If a leg is in a leg actuation singular configuration, the actuated joints in this leg cannot be actuated even if the actuated joints in other legs are released. A formula is revealed that produces a unique current solution to the FDA for a given set of inputs. The input space is also revealed for the quadratic spherical parallel manipulator in order to guarantee that the robot works in the same assembly mode. This work may facilitate the control of the quadratic spherical parallel manipulator.
Novel Transmissibility Shaping Control for Regenerative Vehicle Suspension Systems
Authors: Song Xubin , Cao Dongpu
Published: March 2011

This research proposes a novel transmissibility shaping control (T-shaping Control) method and explores its potential performance benefits for active vehicle suspension systems with energy-regeneration [1]. The proposed model-free T-shaping control integrates a range of sub-strategies based on the frequency information extracted from measured dynamic signals. Each strategy is designed to function dominantly in a certain frequency range to achieve a desirable (or optimal) transmissibility of vehicle responses for enhanced vehicle dynamic performance and safety. Different sub-strategies employed for different frequency ranges consist of stiffness control, skyhook control, groundhook control, and variable damping. In order to demonstrate the effectiveness of this proposed control method, a novel tunable compressible fluid strut (CFS) integrating with digital displacement pump motor (DDPM) is used to form an energy-regenerative controllable vehicle suspension system [2–4]. Two vehicle models, including quarter-car and full-vehicle models, are employed to investigate the dynamic performance of a road vehicle with the proposed T-shaping control and novel regenerative suspension system. The results demonstrate the effectiveness and considerable performance enhancements of the proposed novel T-shaping control applied to the novel CFS suspension system in a very energy-efficient manner.
System RBDO With Correlated Variables Using Probabilistic Re-Analysis and Local Metamodels
Authors: Kuczera Ramon C. , Mourelatos Zissimos P. , Nikolaidis Efstratios
Published: March 2011

A simulation-based, system reliability-based design optimization (RBDO) method is presented that can handle problems with multiple failure regions and correlated random variables. Copulas are used to represent dependence between random variables. The method uses a Probabilistic Re-Analysis (PRRA) approach in conjunction with a sequential trust-region optimization approach and local metamodels covering each trust region. PRRA calculates very efficiently the system reliability of a design by performing a single Monte Carlo (MC) simulation per trust region. Although PRRA is based on MC simulation, it calculates “smooth” sensitivity derivatives, allowing the use of a gradient-based optimizer. The PRRA method is based on importance sampling. One requirement for providing accurate results is that the support of the sampling PDF must contain the support of the joint PDF of the input random variables. The trust-region optimization approach satisfies this requirement. Local metamodels are constructed sequentially for each trust region taking advantage of the potential overlap of the trust regions. The metamodels are used to determine the value of the indicator function in MC simulation. An example with correlated input random variables demonstrates the accuracy and efficiency of the proposed RBDO method.
Design Optimization for Minimizing Actuation Energy of a Dynamic Tripedal Walking Robot: Revisiting the Double Pendulum
Authors: Hays Joe , Hong Dennis , Sandu Corina , Sandu Adrian
Published: March 2011

This work presents a systematic approach to the optimal co-design of a multibody dynamical system’s mechanics and control. The formulation presented is based on a simple double pendulum system, thus allowing a focused illustration of the co-design methodology. However, the ultimate goal is to apply this co-design methodology to the design of a novel Self-excited Tripedal Dynamic Experimental Robot, STriDER. One of STriDER’s design challenges is to determine its mechanical properties and control inputs that minimize the amount of externally supplied actuation energy required to take a single step. Past STriDER prototypes have successfully taken highly efficient dynamic steps, however, these former prototypes required significant manual ‘tweaking’ of its mechanical parameters to realize these steps. Additionally, STriDER’s optimal joint trajectories and actuation inputs have not been outputs of the previous design process. This work provides the first systematic process for the optimal co-design of a controlled multibody dynamic system such as STriDER.
Swirl Effects on Distributed Combustion for Near Zero Emission Gas Turbine Application
Authors: Khalil Ahmed E. E. , Arghode Vaibhav K. , Gupta Ashwani K.
Published: March 2011

Previous investigations of Colorless Distributed Combustion (CDC) demonstrated significant improvement in combustor’s performance. CDC is characterized by high recirculation of product gases, fast mixing, spontaneous ignition and distributed reaction, leading to avoidance of hotspots and much lower NOx emissions. In this investigation, CDC is sought with focus on tailored mixture preparation before ignition using swirl and achieving distributed combustion for developing near zero emission combustion under gas turbine combustion conditions. Numerical and experimental investigations have been performed on a cylindrical combustor. Different fuel injection and hot gases exit arrangements have been considered. Air was injected tangentially to produce vortical structure in the flow and produce high swirl intensity. Results obtained show ultra low NO emissions (∼3 PPM) at high heat release intensity of 36 MW/m3-atm at an equivalence ratio (Φ) of 0.6. The role of premixed and diffusion combustion is also examined.
Partitioned Neural Network Control and Hierarchical Fuzzy Logic Control for Space Flexible Manipulator With Unknown Parameters
Authors: Huang Dengfeng , Chen Li
Published: March 2011

The trajectory tracking and vibration suppression control of free-floating space flexible manipulator with an attitude controlled base are discussed. With the law of conservation of momentum, the Lagrangian principle is utilized to model the dynamic function of the space flexible manipulator incorporating the assumed modes method. Using singular perturbation theory, a slow subsystem describing the rigid motion and a fast subsystem corresponding to the flexible motion are obtained. Then, a two-time scale controller for coordinated motion between the base’s attitude and the manipulator’s joints of space flexible manipulator system is designed. The slow-subsystem partitioned neural network controller dominates the trajectory tracking of coordinated motion in the presence of unknown parameters. The fast-subsystem controller damps out the vibration of the flexible link by hierarchical fuzzy logic controller. Numerical simulation results illustrate that the proposed controller is reliable and effective.
Multi-Objective Design and Tolerance Allocation for Single- and Multi-Level Systems
Authors: Hung Tzu-Chieh , Chan Kuei-Yuan
Published: March 2011

In this work we develop a method to perform simultaneous design and tolerance allocation for engineering problems with multiple objectives. Most studies in existing literature focus on either optimal design with constant tolerances or the optimal tolerance allocation for a given design setup. Simultaneously performing both design and tolerance allocation with multiple objectives for hierarchical systems increases problem dimensions and raises additional computational challenges. A design framework is proposed to obtain optimal design alternatives and to rank their performances when variations are present. An optimality influence range is developed to aid design alternatives selections with an influence signal-to-noise ratio that indicates the accordance of objective variations to the Pareto set and an influence area that quantifies the variations of a design. An additional tolerance design scheme is implemented to ensure that design alternatives meet the target tolerance regions. The proposed method is also extended to decomposed multi-level systems by integrating traditional sensitivity analysis for uncertainty propagation with analytical target cascading. This work enables decision-makers to select their best design alternatives on the Pareto set using three measures with different purposes. Examples demonstrate the effectiveness of the method on both single- and multi-level systems.
Motion Plan of a Parallel Kinematic Machine Based on Stiffness Control
Authors: Chi Zhongzhe , Zhang Dan , Liang Qiaokang
Published: March 2011

This paper proposes a design for a machine tool based on a parallel kinematic manipulator with three degrees of freedom, including rotations about x and y axis and translation along z axe. Based on the investigated displacement and inverse kinematics, the system stiffness of the parallel manipulator is conducted. Then in order to observe the highest system stiffness single and multi objective optimizations are performed in terms of rotation angles about x and y axis and translation displacement along z axe. Finally, a case study of tool path planning is presented to demonstrate the application of stiffness mapping.
Theoretical and Experimental Characterization of the 34.6 2D Lattice Material
Authors: Elsayed Mostafa S. A. , Pasini Damiano
Published: March 2011

In this paper, the effective mechanical properties of the 34.6 lattice material are characterized theoretically and experimentally. The characterized properties include the stiffness and the strength of the material. A detailed description of the design procedure of the test specimens is presented. Three quasi-static tests are performed, namely, uniaxial tension, uniaxial compression and pure shear. The comparison of the experimental data to the theoretical results shows that the former are in good agreement with the latter. The maximum error obtained of 13% is acceptable according to the literature on experimental studies of cellular solids.
Modified Reduced Gradient With Realizations Sorting for Hard Equality Constraints in Reliability-Based Design Optimization
Authors: Ho Chun-Min , Chan Kuei-Yuan
Published: March 2011

In this work, the presence of equality constraints in reliability-based design optimization (RBDO) problems is studied. Relaxation of soft equality constraints in RBDO and its challenges are briefly discussed while the main focus is on hard equalities that can not be violated even under uncertainty. Direct elimination of hard equalities to reduce problem dimensions is usually suggested; however, for nonlinear or black-box functions, variable elimination requires expensive root-finding processes or inverse functions that are generally unavailable. We extend the reduced gradient methods in deterministic optimization to handle hard equalities in RBDO. The efficiency and accuracy of the first and the second order predictions in reduced gradient methods are compared. Results show the first order prediction being more efficient when realizations of random variables are available. A gradient-weighted sorting with these random samples is proposed to further improve the solution efficiency of the reduced gradient method. Feasible design realizations subject to hard equality constraints are then available to be implemented with the state-of-the-art sampling techniques for RBDO problems. Numerical and engineering examples show the strength and simplicity of the proposed method.
Automated Design Synthesis of Articulated Heavy Vehicles With Active Trailer Steering Systems
Authors: Islam Md Manjurul , He Yuping , Webster Timothy D.
Published: March 2011

This paper presents an automated design synthesis approach for articulated heavy vehicles (AHVs) with active trailer steering (ATS) systems. AHVs have poor maneuverability when traveling at low speeds. Moreover, AHVs exhibit unstable motion modes at high speeds. To address the problem of maneuverability, ‘passive’ trailer steering systems have been developed. These systems improve low-speed performance, but feature with low lateral stability at high speeds. Some ATS systems have been proposed to improve highspeed lateral stability. However, these systems typically degrade maneuverability when applied at low speeds. To tackle this conflicting design problem, a systematic method is proposed for the design of AHVs with ATS systems. This new design method has the following features: the optimal active design variables of the ATS systems and the optimal passive design variables of the vehicle are identified in a single design loop; in the design process, to evaluate the vehicle performance measures, a driver model is introduced and it ‘drives’ the vehicle model based on the well-defined testing specifications. Through the design optimization of an ATS system for an AHV with a tractor and a full trailer, this single design loop (SDL) method is compared against a published two design loop (TDL) method. The benchmark investigation shows that the former can determine better trade-off design solutions than those derived by the latter. This SDL method provides an effective approach to automatically implement the design synthesis of AHVs with ATS systems.
Reverse Engineering of Experimental Tests Results of Ballistic Impact for the Validation of Finite Element Simulations
Authors: Manes Andrea , Magrassi Grazia , Giglio Marco , Bordegoni Monica
Published: March 2011

In this paper the set up and the carrying out of experimental ballistic tests on a tail rotor transmission shafts for helicopter, which are impacted by a 7.62 NATO projectile, are presented. After the tests, a 3D acquisition of the impacted area on each shaft has been performed in order to acquire exactly the shape of the damage. The acquisition has been carried out with a 3D range camera. The experimental activities have been compared with the results of a numerical simulation of the impact, which has been computed with an explicit finite element code. The direct comparison has been done by superimposing the two meshes (from FE analysis and from 3D acquisition). This method has proved to be effective for identifying analogies and differences and for giving the possibility to promote a “quantitative” discussion with the aim of improving the accuracy of the numerical models and simulation conditions. The adoption of the Reverse Engineering practice has proved to be a powerful method for integrating and comparing the simulation data with real data, and give suggestions to further analysis.
Creating Curve Based on Mathematical Complexity and Its Kansei Evaluation
Authors: Okubo Masashi , Togo Akiya
Published: March 2011

Recently, we have often the opportunity to shop for something on the computer display connected to the Internet. However, it is often said that the product arrived at the home is something different from it presented on the computer display. We have studied into the differences between the shape evaluation in virtual space and in real space. And it is indicated that the shape evaluation in virtual space is slightly difference from it in real space, especially, in case of evaluation of product which has the complex contour [1]. In this research, we are focusing on the complexity of contour. The complexity is defined by mathematical methods, for example, Hurst exponent in fractal geometry. In this paper, we have proposed the algorithm which makes the curve lines based on the Hurst exponent. And using these curve lines made by proposed method, we have confirmed that the mathematical complexity is equal to the complexity which people feel by sensory evaluation. The result shows that Hurst exponent almost can show the complexity which people feel, however, it is difficult in case of the cyclic curves.
Improving Student Participation in Oral Presentation of a Project-Based Engineering Design Course in a Large-Class Setting
Authors: Hsu Yeh-Liang , Yang Che-Chang
Published: March 2011

Arranging oral presentations has always been very difficult and ineffective in our large project-based engineering design class of about 110 students each year. This paper presents a scheme of implementing peer evaluation to improve students’ participation and learning outcome in the oral presentation sessions. Basically, students were asked to grade and comment on oral presentations by other students in a pre-defined manner. The effect of oral presentations with/without the intervention of peer evaluation was compared. Our data and questionnaire results showed, with careful design of the format, peer evaluation indeed improved students’ participation in oral presentations, naturally leading to more serious and positive learning attitude, and eventually a better learning outcome.
Singularities of Single-DOF Spherical Mechanisms Identified by Means of Pole Axes’ Properties
Authors: Di Gregorio Raffaele
Published: March 2011

Instantaneous pole axes (IPAs) play, in spherical-mechanism kinematics, the same role as instant centers in planar-mechanism kinematics. IPA-based techniques have not been proposed yet for the singularity analysis of spherical mechanisms, even though instant-center-based algorithms have been already presented for planar mechanisms’ singularity analysis. This paper addresses the singularity analysis of single-dof spherical mechanisms by exploiting the properties of pole axes. A general method for implementing this analysis is presented. The presented method relies on the possibility of giving geometric conditions for any type of singularity, and it is the spherical counterpart of an instant-center-based algorithm previously proposed by the author for single-dof planar mechanisms. It can be used to generate systems of equations useful either for finding the singularities of a given mechanism or to synthesize mechanisms that have to match specific requirements about the singularities.
Second-Order Reliability Method With First-Order Efficiency
Authors: Du Xiaoping , Zhang Junfu
Published: March 2011

The widely used First Order Reliability Method (FORM) is efficient, but may not be accurate for nonlinear limit-state functions. The Second Order Reliability Method (SORM) is more accurate but less efficient. To maintain both high accuracy and efficiency, we propose a new second order reliability analysis method with first order efficiency. The method first performs the FORM and identifies the Most Probable Point (MPP). Then the associated limit-state function is decomposed into additive univariate functions at the MPP. Each univariate function is further approximated as a quadratic function, which is created with the gradient information at the MPP and one more point near the MPP. The cumulant generating function of the approximated limit-state function is then available so that saddlepoint approximation can be easily applied for computing the probability of failure. The accuracy of the new method is comparable to that of the SORM, and its efficiency is in the same order of magnitude as the FORM.
An Ontological Approach to Manufacturing Supplier Discovery in Virtual Markets
Authors: Ameri Farhad , McArthur Christian
Published: March 2011

Manufacturing supply chains are increasingly becoming global, virtual and short-lived in order to improve their agility and dynamic adaptability to rapid changes in today’s volatile market. In this context, online marketplaces for manufacturing services have become attractive venues for rapid development of supply chain relationships. Despite their numerous benefits, the existing online markets have failed in adequately automating the supply chain deployment process. Heavy reliance of the existing online markets on human agents for formulating supplier queries and evaluating the obtained results can be mainly attributed to the informal nature of the information models used in these markets. To enable active involvement of machine agents in supply chain deployment, the underlying information models that support online markets should represent the semantics of information in a formal and machine-interpretable fashion. This paper introduces Manufacturing Service Description Language (MSDL) as a formal ontology for description of suppliers’ capability at different levels of abstraction including process-level, machine-level, and system level. Also, an agent-based framework is proposed in this paper that facilitates automated discovery and evaluation of potential manufacturing partners based on the MSDL description of the services they provide.
Beam Constraint Model: A Non-Linear Strain Energy Formulation for Generalized Two-Dimensional Beam Flexures
Authors: Awtar Shorya , Sen Shiladitya
Published: March 2011

In the past, we have introduced the Beam Constraint Model (BCM), which captures pertinent non-linearities to predict the constraint characteristics of a generalized beam flexure in terms of its stiffness and error motions. In this paper, a non-linear strain energy formulation for the beam flexure, consistent with the transverse-direction load-displacement and axial-direction geometric constraint relations in the BCM, is presented. An explicit strain energy expression, in terms of beam end-displacements, that accommodates generalized loading conditions, boundary conditions, initial curvature, and beam shape is derived. Using the Principle of Virtual Work, this strain energy expression for a generalized beam is employed in determining the load-displacement relations, and therefore constraint characteristics, for flexure mechanisms comprising multiple beams. The benefit of this approach is evident in its mathematical efficiency and succinctness, which is to be expected with the use of energy methods. All analytical results are validated to a high degree of accuracy via non-linear Finite Element Analysis. Furthermore, the proposed energy formulation leads to new insights into the nature of the BCM.
Design of a Large Range XY Nanopositioning System
Authors: Awtar Shorya , Parmar Gaurav
Published: March 2011

Achieving large motion range (> 1 mm) along with nanometric motion quality (< 10 nm), simultaneously, has been a key challenge in nanopositioning systems. Practical limitations associated with the individual physical components (flexure bearing, actuators, and sensors) and their integration, particularly in the case of multi-axis systems, have restricted the range of current nanopositioning systems to about 100 μm. This paper presents a novel physical system layout, with a parallel-kinematic XY flexure mechanism at its heart, that provides a high degree of decoupling between the two motion axes by avoiding geometric over-constraints, provides actuator isolation that allows the use of large-stroke single-axis actuators, and enables a complementary end-point sensing scheme that employs commonly available sensors. These attributes help achieve an unprecedented 10 mm × 10 mm motion range in the proposed nanopositioning system. Having overcome the physical system design challenges, a dynamic model of proposed nanopositioning system is created and verified via system identification methods. In particular, dynamic non-linearities associated with the large displacements of the flexure mechanism and resulting controls challenges are identified. The physical system is fabricated, assembled, and tested to validate its simultaneous large range and nanometric motion capabilities. Preliminary closed-loop test results, which highlight the potential of this new design configuration, are presented.
A Robust Solution of the Spherical Burmester Problem
Authors: Angeles Jorge , Bai Shaoping
Published: March 2011

The problem of spherical four-bar linkage synthesis is revisited in this paper. The work is aimed at developing a robust synthesis method by taking into account both the formulation and the solution method. In addition, the synthesis of linkages with spherical prismatic joints is considered by treating them as a special case of the linkages under study. A two-step synthesis method is developed, which sequentially deals with equation-solving by a semigraphical approach and branching-detection. Examples are included to demonstrate the proposed method.
Assessment of Advertising Effectiveness Through Audience’s Eye Movements
Authors: Jin Shize , Zeng Yong , Wang Chun
Published: March 2011

The evaluation of advertisement effectiveness during the advertisement design phase and pre-launch phase is critical for the advertisement’s success in the targeted market. This evaluation should predict advertisement’s final performance as accurately as possible. In today’s advertisement business, questionnaire-based evaluation methods, such as attitude and opinion rating are widely used. To obtain good survey results, high quality questionnaires and proper interviewing procedures have to be developed with the support of the competent execution and supervision. These activities are usually costly even though some of them can be conducted online. This paper proposes a novel method for assessing the advertisement effectiveness through the automated capturing and analyzing of audiences’ eye movements. This method is based on the assumption that some attributes of audiences’ eye movements are correlated to their visual attention defined in the context of advertisement effectiveness. To validate our research hypotheses, experiments were conducted. In the experiments, subjects were required to watch several advertisements in sequence and the subjects’ eye movement data were collected simultaneously. By analyzing the data patterns and comparing them with the effectiveness evaluation obtained from questionnaire-based method, we found that the proposed method produces similar evaluations to those resulted from the traditional attitude and opinion rating method.
Optimal Plug-In Hybrid Vehicle Design and Allocation for Minimum Life Cycle Cost, Petroleum Consumption and Greenhouse Gas Emissions
Authors: Shiau Ching-Shin Norman , Peterson Scott B. , Michalek Jeremy J.
Published: March 2011

Plug-in hybrid electric vehicle (PHEV) technology has the potential to help address economic, environmental, and national security concerns in the United States by reducing operating cost, greenhouse gas (GHG) emissions and petroleum consumption from the transportation sector. However, the net effects of PHEVs depend critically on vehicle design, battery technology, and charging frequency. To examine these implications, we develop an integrated optimization model utilizing vehicle physics simulation, battery degradation data, and U.S. driving data to determine optimal vehicle design and allocation of vehicles to drivers for minimum life cycle cost, GHG emissions, and petroleum consumption. We find that, while PHEVs with large battery capacity minimize petroleum consumption, a mix of PHEVs sized for 25–40 miles of electric travel produces the greatest reduction in lifecycle GHG emissions. At today’s average US energy prices, battery pack cost must fall below $460/kWh (below $300/kWh for a 10% discount rate) for PHEVs to be cost competitive with ordinary hybrid electric vehicles (HEVs). Carbon allowance prices have marginal impact on optimal design or allocation of PHEVs even at $100/tonne. We find that the maximum battery swing should be utilized to achieve minimum life cycle cost, GHGs, and petroleum consumption. Increased swing enables greater all-electric range (AER) to be achieved with smaller battery packs, improving cost competitiveness of PHEVs. Hence, existing policies that subsidize battery cost for PHEVs would likely be better tied to AER, rather than total battery capacity.
System for 3D Form Generation and Impression Analysis Based on Emotional Words: “Kansei Words”
Authors: Aoyama Hideki , Miyauchi Shigeto
Published: March 2011

Appearance design is becoming an increasingly important factor for determining product value as well as product functions as customer preference continues to diversify, leading to growing demands for sophisticated designs. Current CAD systems are not effective for design because they lack functions to express the designer’s sensitivity (Kansei). In the first step of appearance design, the designer embodies the shape image from concepts. In this stage, if 3D models can be easily built and corrected based on KANSEI, the process of embodying the shape image becomes easy. In addition, product design must also reflect customer needs. The objective of this study is therefore to develop a design system that can construct and analyze 3D car models based on terms expressing “Kanse”. In this study, these terms are defined as “Kansei words”.
Reverse Engineering for Spotting of Sheet Metal Forming Parts
Authors: Schoene Christine , Stelzer Ralph , Schmidt Ulf , Suesse Dietmar
Published: March 2011

The paper elucidates how to connect forming process simulation with innovative measurement- and analysis equipment thereby taking into account the machine influences. Reverse Engineering use 3D-Scanning data of sheet metal forming dies. Following this paradigm, the models simulation relies on are refined, and spotting of forming dies is subjected to a scientific analysis. That means, that with Reverse Engineering, “extended process engineering” is verified at the real spotting procedure, the comparison of simulation- and measuring results is used to evaluate how close the investigated models are to reality, extending the optimisation algorithms used for springback compensation to die spotting, the modification of the die topology will be carried out automatically thanks to new software functions.
Vibration and Buckling Response of Width Tapered Laminated Composite Beams Using Ritz Method for Rotorcraft Blade
Authors: Badagi Vijay Kumar , Ganesan Rajamohan
Published: March 2011

In this study, Symmetric cross-ply linear width tapered laminated composite beam is considered. Due to the variety of width tapered composite beams and the complexity of the analysis, no closed-form analytical solution is available at present regarding free vibration response. Therefore in the present work, the Ritz method is used for the free vibration analysis with considering uni-axial compressive and tensile force. The elastic stiffness of the width tapered composite beam is analyzed compared to uniform laminated composite beam. Free vibration which is significant to investigate the dynamic characteristics of the structure using Ritz method with and without effect of axial tensile and compressive force is analyzed. The analysis is based on 1D laminated beam theory. The governing equations are obtained by means of Hamilton’s principle. Tsai-Wu failure analysis is considered to find the tensile and compressive failure force for each ply in the laminate. Buckling analysis is conducted to find the critical buckling force for the laminated composite beam-column subjected to different sets of boundary conditions. Simply supported, Clamped-free, Clamped-Clamped edge boundary conditions are considered. A detailed parametric study is conducted on tapered composite beams made of NCT/301 graphite-epoxy to investigate the effects of the ratio of the width of the thick section to thin section, boundary conditions, effects of axial and compressive force on natural frequency and buckling analysis.
Introducing Design Rigidity to Model Unexpected Disturbances in a DSM-Based Design Process
Authors: Platanitis George , Barari Ahmad , Pop-Iliev Remon
Published: March 2011

Agile design engineering systems require flexible processes that can adapt rapidly for fast response to dynamic changes in the design requirements due to the market demands and/or internal or external constrains and limitations, without compromising the cost and quality of the design process and design process’ upstream activities, particularly the manufacturing and production processes. These changes in the design requirements can occur as unpredictable events at any time, delaying the convergence of the design process to a feasible solution. In this paper, the flexibility of design process versus an unpredicted event is studied and modeled using the notion of a dynamic index of rigidity for the design process. Using the Design Structure Matrix (DSM)-based definition of the sequence and technical relationship of design tasks, a dynamic response to an unexpected change in the design requirements and the additional necessary iterations in the design process are studied and modeled using the dynamic rigidity of the design process.
Trajectory Control for an Innovative Rapid Freeze Prototyping System
Authors: Barnett Eric , Angeles Jorge , Pasini Damiano , Sijpkes Pieter
Published: March 2011

The subject of this paper is trajectory control for an Adept Cobra 600 robot, which has been retrofitted for additive ice construction. Since this application is quite different from typical SCARA applications, considerable development is needed for trajectory control and data flow. We first outline the trajectory control system requirements, as well as the limitations of the robot hardware. Different control options are proposed and their merits and demerits are discussed; the most suitable scheme is judged to be custom programming in Adept’s V+ programming language, with trajectories expressed in the Cobra 600 joint space. With this control scheme, all system requirements are met, data manipulation is most efficient, and the system is readily adaptable for planned modifications. A specific data format is needed in order to implement this control scheme; we describe how trajectory data produced with our part-slicing algorithm is converted to the format required for the V+ programs.
Workspace Investigation of Wire-Actuated Parallel Manipulators With Uncertainties in Wire Connections
Authors: Notash Leila , McColl Derek
Published: March 2011

In this article, the effect of uncertainties in wire connections on the workspace generation of wire-actuated parallel manipulators is investigated. The geometric representations of uncertainties in the attachments points of wires to the base and to the mobile platform are developed. Two methods for workspace generation with uncertainty are presented. The first method is based on the calculation of positive wire tensions derived from the static force/moment balance. The second method is based on the direction of the wire forces applied to the mobile platform, and does not take into account the wire tensions. The proposed methods are applied for the workspace generation of two planar wire-actuated parallel manipulators.
Design of an Anti-Idling System for Police Vehicles
Authors: Fan Brian , Khajepour Amir , Kazerani Mehrdad
Published: March 2011

A configurable, modular, and flexible vehicle model utilizing scalable powertrain components has been developed at the University of Waterloo. The configurable vehicle model is modified to create an anti-idling system for police vehicles, where an additional battery is utilized to reduce the amount of engine idling time. The goal of the design study is to perform modeling and simulation of the anti-idling system from a financial cost point of view, in order to investigate the potential cost and fuel reduction over a conventional system. The cost function includes the total cost of the battery, the equivalent fuel consumption, and the carbon tax over a period of five years. It is concluded that the anti-idling system demonstrated significant fuel and cost reduction compared to one without. Furthermore, it is found that depending on the SOC threshold of the power management logic, the duration of time over which the engine is activated varied in a non-linear fashion. Future works include performing optimization of the power management logic and also investigates the effects of utilizing different battery types and sizes.
A Framework Supporting Life-Cycle Guidance for Fabricating Micro Components by Compression Moulding
Authors: Farrugia P. J. , Vella P. , Mifsud M.
Published: March 2011

Micro-products and components are rapidly increasing in a range of sectors. This demand requires industrial technologies capable of mass producing polymer micro products at a reasonable price. These two requirements are satisfied by the use of replication technologies such as micro compression moulding (μCM). A literature review that we conducted revealed that there is indeed little if any work explicitly related to the domain of micro compression moulding. In addition, a design methodology in micro manufacturing is still in its infancy and that there is a shortage of relevant DFX guidelines. Thus, this research aims at developing a framework for a computer-based tool whereby micro-product stakeholders are guided to select the correct mould features, material, machine and process parameters for fabricating components via micro compression moulding. The paper presents a framework developed to meet this goal. A proof-of-concept tool has also been implemented based on this framework. This tool was evaluated by typical case studies and also presented to a number of experts in the field. Preliminary evaluation results provide a degree of evidence that technology based on the framework contributes a step towards providing guidance for the design and manufacture of mould tools for fabricating μ-components by compression moulding. Another contribution of this paper is the preliminary fabrication platform using μCM. Future work is however required mainly to assess the economic feasibility of the fabrication platform, to address the limitations of the implemented tool, and to assess its effectiveness in practice.
Virtual Reality Based Engineering Collaboration as Part of the Product Lifecycle Management
Authors: Stelzer Ralph H.
Published: March 2011

Virtual reality (VR) is an established technology in certain sectors of industry. But because of the cost and effort involved, VR has so far mostly been used in large companies (e.g. the automotive industry). Today, hardware price trends coupled with the availability of new, easier-to-use equipment (economical powerwalls, autostereoscopic displays) are making VR increasingly attractive for smaller firms. Despite this, the considerable effort involved in providing the necessary data and, more importantly, the lack of integration with current development processes represents a continued barrier to widespread use which would allow companies to benefit from the excellent visualization quality and ease of handling in VR models. This article presents a process integration solution in which the VR component changes its position away from a visualization solution to the basic collaboration interface of a Product Lifecycle Management (PLM) environment. This allows VR to be incorporated into a landscape of heterogeneous conventional 3D-CAD workstations and simulation applications. The solution takes the form of a multidirectional connection via the PLM system which makes it possible not only to process and display geometries but also to simulate movements and depict non-geometrical product information. This concept includes the use of gestures and tracked mobile devices to interact in the VR environment and to get additional information.
Vibration Control of Vehicles With Flexible Structure Using Optimum Tuned-Mass Dampers
Authors: Goodarzi Avesta , Pandarathil Neda , Esmailzadeh Ebrahim
Published: March 2011

Vibrations resulting from flexural motion of elastic vehicle structures are of particular significance to the ride comfort of vehicles. Tuned-mass dampers (dynamic vibration absorbers) are among the most commonly used devices for vibration suppression. In this paper the application of optimum tuned-mass dampers is addressed, that can be used to reduce annoying flexibility originated vibration. A newly developed flexible model is representing the vehicle with eight-degree-of-freedom (8-DOF) with a systematic approach to select the optimum locations of the absorbers. Using passive vibration absorbers and applying the min-max optimization method to find the optimum values of the design parameters. Simulation results for a case study bus with flexible structure confirm the strength of the proposed design. For those who wish to pursue future research on this subject few suggestions are given.