bluuebunny/crossref_metadata_2025 huggingface dataset:
A Novel Method for Producing Low Cost Dynamometric Wheels
Authors: Gutiérrez-López María D. , García de Jalón Javier
Published: February 2014

In this paper, a novel method for producing dynamometric wheels that measure the forces and moments acting at the tyre/road contact patch is presented. Those forces and moments are obtained from the strain signals measured at different points of the original wheel of the vehicle with strain gauges. These signals do not only depend on the forces and moments that are to be determined, but also on other factors such as the angle of rotation of the wheel, the temperature, the centrifugal forces… In order to obtain the forces and moments acting at the contact patch, the signals coming from the strain gauges are linearly combined in such a way that at least another six signals are obtained, that are independent on the rotation of the wheel, the temperature and the centrifugal forces. From these new signals, the forces and moments are computed by solving two systems of linear equations with three unknowns each.
Virtual Life and Performance Modeling of Aerospace Spiral Bevel Gears
Authors: Ames Eric C. , Pulikollu Raja V.
Published: February 2014

Spiral bevel gears are widely used in the tail rotor drive trains of most rotorcraft. The loads associated with the tail rotor drive train are generally much more variable than those in the main rotor drive train primarily resulting from maneuvers. Over the life of any particular military rotorcraft it is not uncommon for the aircraft’s operating gross weight to steadily increase, causing the aircraft to fly at higher mean power levels and thus increasing the operating load spectrum associated with the tail rotor drive train. Special missions and equipment such as pulling a mine sweeping sled or very high altitude high gross weight assaults can put severe load demands on the tail drive train. This paper details an effort conducted to evaluate the effects of short to moderate duration overloads on the spiral bevel gears of the UH-60 helicopter tail rotor drive train. The focus of the effort was on the Tail Take-off gear mesh (TTO). An initial analytical assessment of the effect of loads above the endurance limit was conducted using an American Gear Manufacturers Association (AGMA) based approach. To confirm the validity of this approach, overload testing of the TTO gear mesh was conducted by the U.S. Army’s Aviation Applied Technology Directorate at the Navy’s test facility in Paxtuent River MD. Following the testing, the gear tooth bending and surface fatigue lives were analyzed using a microstructure based probabilistic tool developed by Sentient Corporation. The tool, known as Digital Clone was able to run hundreds of virtual tests that closely simulated the actual testing thus providing a low cost method for increasing the confidence associated with the effects of short to moderate high transient loads.
Geometric Reasoning for Assembly Planning of Large Systems
Authors: Eftekharian Ata A. , Manion Charlie , Campbell Matthew I.
Published: February 2014

Assembly planning is an important task for manufacturing industrial products. The ability to automate and optimize the process is crucial as it can improve the production time, cost and efficiency. In general, the planning procedure involves two main reasoning stages, one is based on geometric reasoning and the other is based on AI tree-search. In this article, a novel approach to automate the geometric reasoning stage for large assembly systems is proposed. This technique provides a fast and accurate measure of capturing feasible spatial interactions and relationships between elements of a CAD assembly with no manual interventions. These results are then used by a suite of AI planning tools to generate optimal assembly sequences. The algorithm has been tested on a variety of examples resembling real products and results show the efficiency and effectiveness of the algorithm.
A New Method for Design Decisions Using Decision Topologies
Authors: Pandey Vijitashwa , Mourelatos Zissimos P.
Published: February 2014

This paper shows how reliability block diagrams can be used as a decision making tool. The premise behind the idea is that classical decision analysis while very powerful, does not provide tractability in assessing utility functions and their use in making decisions. Our recent work has shown that visual representation of systems using a reliability block diagram can be used to describe a decision situation. In decision making, we called these block diagrams decision topologies. We show that decision topologies can be used to make many engineering decisions and can replace decision analysis for most decisions. The paper proves that at the limit, using decision topologies is entirely consistent with decision analysis for both single attribute and multiattribute cases. The main advantages of the proposed method are that (1) it provides a visual representation of a decision situation, (2) it can easily model tradeoffs, (3) it allows binary attributes, (4) it can be used when limited information is available, and (5) it can be used in a low-fidelity sense to quickly make a decision. The paper details the theoretical basis of the proposed method and highlights its benefits. An example is used to demonstrate how decision topologies can be used in practice.
Vibration Based Sun Gear Damage Detection
Authors: Hood Adrian , LaBerge Kelsen , Lewicki David , Pines Darryll
Published: February 2014

Seeded fault experiments were conducted on the planetary stage of an OH-58C helicopter transmission. Two vibration based methods are discussed that isolate the dynamics of the sun gear from that of the planet gears, bearings, input spiral bevel stage, and other components in and around the gearbox. Three damaged sun gears: two spalled and one cracked, serve as the focus of this current work. A non-sequential vibration separation algorithm was developed and the resulting signals analyzed. The second method uses only the time synchronously averaged data but takes advantage of the signal/source mapping required for vibration separation. Both algorithms were successful in identifying the spall damage. Sun gear damage was confirmed by the presence of sun mesh groups. The sun tooth crack condition was inconclusive.
Evaluation and Search of Assembly Sequences in Large Systems
Authors: Eftekharian Ata A. , Poladi Ranjith , Campbell Matthew I.
Published: February 2014

In order to build a comprehensive automated assembly planning tool, three important tasks must be accomplished: generating feasible assembly sequences, evaluating the quality of a sequence, and the search method for finding the optimal plan. This paper describes a novel approach to the latter two. The evaluation approach combines empirical data and geometric reasoning techniques to arrive at estimates of assembly time for any generic assembly model. The evaluation is constantly invoked from a tree-search method that only searches amongst valid assembly operations. The algorithm has been tested on a variety of examples ranging from simple to complex assemblies.
Design of a Biologically-Inspired Chemical Sensor
Authors: Nagel Jacquelyn K. S.
Published: February 2014

Sensors are an integral part of many engineered products and systems. Biological inspiration has the potential to improve current sensor designs as well as inspire innovative ones. Mimicking nature offers more than just the observable aspects that conjure up engineering solutions performing similar functions, but also less obvious strategic and sustainable aspects. This paper presents the design of an innovative, biologically-inspired chemical sensor that performs “up-front” processing through mechanical filtering. Functional representation and abstraction were used to place the biological system information in an engineering context, and facilitate the bioinspired design process. Inspiration from the physiology (function) of the guard cell coupled with the morphology (form) and physiology of tropomyosin resulted in multiple concept variants for the chemical sensor. The chemical sensor conceptual designs are provided along with detailed descriptions. Applications of the sensor design include environmental monitoring of harmful gases, and a non-invasive approach to detect illnesses including diabetes, liver disease, and cancer on the breath.
On the Force Capabilities of Two-Degree-of-Freedom Planar Parallel Mechanisms Equipped With Torque Limiters
Authors: Chen Wei , Gosselin Clément
Published: February 2014

Safety is the most important issue that should be considered when designing collaborative robots that are intended to physically interact with humans. This paper investigates the force capabilities of two-degree-of-freedom planar parallel mechanisms that are equipped with torque limiters (safety clutches). Joint torque limiting devices are used in these mechanisms in order to limit the forces that the robot can apply to its environment. Such devices aim at ensuring the safety of the human beings interacting with the robot. However, because the torque-limiting devices are mounted at the joints of the robot, the end-effector force capabilities induced by these devices are dependent on the pose (Jacobian matrix) of the robot. Therefore, the characteristics of the torque limiting devices must be determined at the design stage in order to ensure safety and maximize effectiveness in all possible poses of the robot. Two types of planar two-degree-of-freedom parallel mechanisms are considered in this paper. Their architecture is first described. Then, the force capabilities are studied based on the Jacobian matrices. The maximum force that can be applied at the end-effector for given torque limits (safety index) is determined together with the maximum isotropic force (effectiveness) that can be produced. The ratio between these two forces, referred to as the force efficiency, can be considered as a performance index. Finally, some numerical results are proposed which can provide insight into the design of cooperation robots based on parallel architectures.
Numerical Scheme for Generalized Isoparametric Constraint Variational Problems With A-Operator
Authors: Pandey Rajesh K. , Agrawal Om P.
Published: February 2014

This paper presents a numerical scheme for a class of Isoperimetric Constraint Variational Problems (ICVPs) defined in terms of an A-operator introduced recently. In this scheme, Bernstein’s polynomials are used to approximate the desired function and to reduce the problem from a functional space to an eigenvalue problem in a finite dimensional space. Properties of the eigenvalues and eigenvectors of this problem are used to obtain approximate solutions to the problem. Results for two examples are presented to demonstrate the effectiveness of the proposed scheme. In special cases the A-operator reduce to Riemann-Liouville, Caputo, Riesz-Riemann-Liouville and Riesz-Caputo, and several other fractional derivatives defined in the literature. Thus, the approach presented here provides a general scheme for ICVPs defined using different types of fractional derivatives. Although, only Bernstein’s polynomials are used here to approximate the solutions, many other approximation schemes are possible. Effectiveness of these approximation schemes will be presented in the future.
Tolerance-Maps for Line-Profiles Constructed From Boolean Operations on Primitive T-Map Elements
Authors: He Y. , Davidson J. K. , Shah Jami J.
Published: February 2014

For purposes of automating the assignment of tolerances during design, a math model, called the Tolerance-Map (T-Map), has been produced for most of the tolerance classes that are used by designers. Each T-Map is a hypothetical point-space that represents the geometric variations of a feature in its tolerance-zone. Of the six tolerance classes defined in the ASME/ANSI/ISO Standards, only one attempt has been made at modeling line-profiles [1], and the method used is an intuitive kinematic description of the allowable displacements of the middle-sized profile within its tolerance-zone. The objective of this paper is to describe an alternative method of construction, one that is much more amenable to computer automation, to obtain the T-Map of any line-profile.

Tolerances on line-profiles are used to control cross-sectional shapes of parts, even mildly twisted ones such as those on turbine or compressor blades. Such tolerances limit geometric manufacturing variations to a specified two-dimensional tolerance-zone, i.e. an area, the boundaries to which are curves parallel to the true profile. The single profile tolerance may be used to control position, orientation, and form of the profile.

The new method requires decomposing a profile into segments, creating a solid-model T-Map primitive for each, and then combining these by the Boolean intersection to generate the T-Map for a complete line profile of any shape. To economize on length, the scope of this paper is limited to line-profiles having any polygonal shape.
Product-Service Integration for the Sustainable Publishing Process
Authors: Liu Ang , Lu Stephen C-Y.
Published: February 2014

Publishing is the process of developing and producing content for distribution to the public. In the past, the publishing process heavily relies on printing as the method of content production. This causes voracious consumption and waste of natural resources. In today’s sweeping trend of digitization that is featured by the increasing popularity of various smart devices, the publishing process is undergoing a profound transition from the traditional printing-reliant publishing model to the new digital publishing model. Such a transition brings great opportunities for the publishing process to achieve better sustainability by evolving towards a product service system. This paper intends to advance the publishing process from the product service integration perspective. Above all, a general product-service integration framework is developed to describe the interdependent relationships among key stakeholders and elements in the publishing value chain. Furthermore, several specific publishing PSS are discussed. Finally, these publishing PSS are evaluated and compared from the value creation perspective.
Rethinking the Comprehensive Test on Qualitative Reasoning for Designers
Authors: Khorshidi Maryam , Shah Jami J. , Woodward Jay
Published: February 2014

A battery of tests assessing the cognitive skills needed for the conceptual design is being developed. Tests on Divergent thinking and visual thinking are fully developed and validated. The first version of the qualitative reasoning test has also been developed; this paper focuses on the lessons learned from testing of the first version of the test (alpha version) and the improvements made to it since then.

A number of problems were developed for each indicator of the qualitative reasoning skill (deductive reasoning, inductive reasoning, analogical reasoning, and abductive reasoning). Later, a protocol study was done with the problems to make sure that the problems assess the desired skills. The problems were also given to a randomly chosen population of undergraduate senior-level or graduate-level engineering students. Data was collected from the test results on the possible correlations between the problems (e.g. technical and non-technical problems); feedback on clarity, time allocation, and difficulty for each problem was also collected. Based on all of the observed correlations, the average performance of the test takers, and test parameters such as validity, reliability, etc. the beta version of the test is constructed.
Triangle Mesh Based In-Process Workpiece Update for General Milling Processes
Authors: Gong Xun , Feng Hsi-Yung
Published: February 2014

A new methodology for modeling and updating the in-process workpiece geometry in milling is presented in this paper. The methodology is developed for general milling processes, in which the cutter can be any shape and follow any tool path trajectory even with self-intersections. And the in-process workpiece is updated with retained sharp features. The associated procedure starts by modeling both the cutter and the workpiece as closed manifold triangle meshes. The mesh model of the cutter swept volume is then generated from repeatedly sampled mesh vertices of the cutter along its trajectory using the ball-pivoting algorithm. The workpiece is updated by a subtraction Boolean operation between the workpiece and the cutter swept volume. An octree space partitioning algorithm is adopted in order to efficiently obtain the exact triangle-to-triangle intersection points. As the last step, a filling operation is performed around the intersection points to establish the closed manifold updated workpiece geometry. Several case studies have been performed to demonstrate the effectiveness of the proposed methodology.
Experimental Validation of Flexible Multibody Dynamics Beam Formulations
Authors: Bauchau Olivier A. , Han Shilei , Mikkola Aki , Matikainen Marko K. , Gerstmayr Johannes
Published: February 2014

In this paper, the accuracy of the geometrically exact beam formulation and absolute nodal coordinate formulation are studied by comparing their predictions against experimental data referred to as the “Princeton beam experiment.” The experiment deals with a cantilevered beam experiencing coupled flap, lag, and twist deformations. In the absolute nodal coordinate formulation, two different beam elements are used. The first is based on a shear deformable approach in which the element kinematics are described using two nodes. The second is based on a recently proposed approach in which three nodes are used. The numerical results for the geometrically exact beam formulation and the recently proposed three-node absolute nodal coordinate formulation agree well with the experimental data. The two-node beam element predictions are similarly to linear theory. This study suggests that the latest developments of the absolute nodal coordinate formulation must be used to ensure accuracy under complicated loading conditions involving by twist deformation.
Reduced Order Model of Electrostatically Actuated Carbon Nanotube Cantilever Biosensors for Primary Resonance
Authors: Caruntu Dumitru I. , Luo Le
Published: February 2014

This paper investigates electrostatically actuated Carbon Nano-Tubes (CNT) cantilevers biosensors using the Reduced Order Model (ROM) method. Forces acting on the CNT are electrostatic, damping, and van der Waals. The electrostatic actuation is given by soft AC voltage. Van der Waals forces are significant for gaps between the CNT and a ground plate lower than 100 nm. Both forces electrostatic and van der Waals are nonlinear. CNT undergoes nonlinear parametric dynamics. ROM is used to investigate the system under soft excitations and/or weak nonlinearities. The frequency-amplitude response is found in the case of primary resonance and compared to the Method of Multiple Scales (MMS). The CNT biosensor is to be used for mass detection applications.
Experimental Validation of a Model for the Dynamic Analysis of Gear Pumps
Authors: Mucchi Emiliano , Dalpiaz Giorgio
Published: February 2014

This paper concerns the experimental validation of an elastodynamic model of an external gear pump for steering systems in vehicles. The elastodynamic model takes into account the most important phenomena involved in the operation of this kind of machines. Two main sources of noise and vibration can be considered: pressure and gear meshing. An experimental apparatus has been set up for the measurements of the case accelerations and force components in operational conditions. The model was validated by comparison between simulations and experimental results concerning forces and moments: it deals with the external and inertia components acting on the gears, estimated by the model, and the reactions and inertia components on the pump case and the test plate, obtained by measurements. The validation is carried out comparing the level of the time synchronous average in the time domain and the waterfall maps in the frequency domain, with particular attention to identify system resonances. The validation results are globally satisfactory.
Analysis of the Evolution of the Pressure Forces in Variable Displacement Vane Pumps Using Different Approaches
Authors: Mucchi Emiliano , Dalpiaz Giorgio
Published: February 2014

Two models for the estimation of the pressure evolution in high pressure variable displacement vane pumps are proposed: a lumped parameter model and an empirical model. The former has full physical meaning and allows to simulate the behavior of a wide pump range, the latter, based on experimental measurements, can be applied only to a single family of pumps. Both the models can simulate the pressure evolution around the rotor in working conditions. These results are important for the structural design of the pump. Moreover, these models are the first element of a combined model aimed at the dynamic simulation of this type of pump, as a tool for vibro–acoustical optimization.
Hinge-Free Compliant Mechanism Design via the Topological Level-Set
Authors: Suresh Krishnan
Published: February 2014

The objective of this paper is to introduce and demonstrate a new method for the topology optimization of compliant mechanisms. The proposed method relies on exploiting the topological derivative, and it exhibits numerous desirable properties including: (1) the mechanisms are hinge-free, (2) mechanisms with different geometric and mechanical advantages can be generated by varying a single control parameter, (3) a target volume fraction need not specified; instead numerous designs, of decreasing volume fractions, are generated in a single optimization run, and (4) the underlying finite element stiffness matrices are well-conditioned, permitting the use of high-performance iterative solvers. The proposed method and implementation are illustrated through numerical experiments in 2D and 3D.
Control Strategy and Trajectory Planning for Reconfiguration of a vA Based Metamorphic Parallel Manipulator
Authors: Emmanouil Evangelos , Zhang Ketao , Dai Jian S.
Published: February 2014

Mechanisms with reconfigurability have become a trend in development of multi-functional robots which can adapt to unexpected environments and perform complicated tasks. This paper presents a novel metamorphic parallel manipulator with the ability to change its mobility through the phase change of a variable-axis (vA) joint integrated in each limb. The platform has 6 DOFs in the source phase and can reconfigure its mobility to 5, 4 and 3 resorting to redundant actuation. This leads to reconfigurability and multi-functionality of the parallel manipulator characterized by the mobility configuration variation. A control strategy and a trajectory planning algorithm for reconfiguring the mobility configuration of the manipulator are proposed and simulations are carried out to identify a proper way of reconfiguration.
Controllable Rotation Workspace of a Metamorphic Parallel Mechanism With Reconfigurable Universal Joints
Authors: Gan Dongming , Dai Jian S. , Dias Jorge , Seneviratne Lakmal D.
Published: February 2014

This paper introduces a metamorphic parallel mechanism which has three topologies with pure translational, pure rotational and 3T1R degrees of freedom. Mobility change stemming from the reconfigurability of a reconfigurable Hooke (rT) joint is illustrated by change of the limb twist screw systems and the platform constraint screw system. Then the paper focuses on the pure rotational topology of the mechanism of which the rotational center can be altered along the central line perpendicular to the base plane by altering the radial rotational axes in the limbs. Singularity analysis is conducted based on the dependency of constraint forces and actuation forces in a screw based Jacobian matrix. Following these, rotation workspace variation is demonstrated in a 2D projection format using the Tilt-and-Torsion Euler angles based on the actuation limits and joint rotation ranges.
Some Pioneers of the Application of Fractional Calculus
Authors: Tenreiro Machado J. A. , Galhano Alexandra M. S. F.
Published: February 2014

In the last decades fractional calculus (FC) became an area of intense research and development. This paper goes back and draws the time line of FC. We recall also important pioneers that started to apply FC during the beginning of the twentieth century. First we remember Oliver Heaviside, a pioneer in several areas of mathematics, physics and engineering. His operational calculus revealed expressions involving fractional derivatives, a premonition of the progresses that emerged later in the last decades of the twentieth century. Second it is addressed the Cole-Cole electrical relaxation. This model was a seminal work in the application of FC and plays nowadays an important role in many areas of physics and engineering.
Evolutionary Design of Cellular Self-Organizing Systems
Authors: Humann James , Jin Yan
Published: February 2014

In this paper, a genetic algorithm (GA) is used to discover interaction rules for a cellular self-organizing (CSO) system. The CSO system is a group of autonomous, independent agents that perform tasks through self-organization without any central controller. The agents have a local neighborhood of sensing and react only to other agents within this neighborhood. Their interaction rules are a simple set of direction vectors based on a flocking model. The five local interaction rules are assigned relative weights, and the agents self-organize to display some emergent behavior at the system level. The engineering challenge is to identify which sets of local rules will cause certain desired global behaviors. The global required behaviors of the system, such as flocking or exploration, are translated into a fitness function that can be evaluated at the end of a multi-agent based simulation run. The GA works by tuning the relative weights of the local interaction rules so that the desired global behavior emerges, judged by the fitness function. The GA approach is shown to be successful in tuning the weights of these interaction rules on simulated CSO systems, and, in some cases, the GA actually evolved qualitatively different local interaction “strategies” that displayed equivalent emergent capabilities.
An Inverse Approach on Load Identification From Optimally Placed Accelerometers
Authors: Gupta Deepak K. , Dhingra Anoop K.
Published: February 2014

This paper presents an inverse approach for estimating dynamic loads acting on a structure from acceleration time response measured experimentally at finite number of optimally placed accelerometers on the structure. The structure acts as its own load transducer. The approach is based on the standard equilibrium equation of motion in modal coordinates. Modal model of a system is defined by its modal parameters — natural frequencies, corresponding mode shapes and modal damping factors. These parameters can be estimated experimentally from measured data, analytically for simple problems, or from finite element method. For measurement of the acceleration response, there can be a large number of combinations of locations on the structure where the accelerometers can be mounted and the results may be quite sensitive to the locations selected for accelerometer placements. In fact, the precision with which the applied loads are estimated from measured acceleration response depends on the number of accelerometers utilized and their location on the component. Implementation of a methodology to determine the optimum set of accelerometer locations, based on the construction of D-optimal design, is presented to guide the selection of number and locations of accelerometers that will provide the most precise load estimates. A technique based on model reduction is proposed to reconstruct the input forces accurately. A numerical validation that helps to understand the main characteristics of the proposed approach is also presented. The numerical results reveal the effectiveness and utility of the technique.
A Framework for System Design Optimization Based on Maintenance Scheduling With Prognostics and Health Management
Authors: Yu Bo Yang , Honda Tomonori , Zubair Syed , Sharqawy Mostafa H. , Yang Maria C.
Published: February 2014

The optimal maintenance scheduling of systems with degrading components is highly coupled with the design of the system and various uncertainties associated with the system, including the operating conditions, the interaction of different degradation profiles of various system components, and the ability to measure and predict degradation using prognostics and health management (PHM) technologies. Due to this complexity, designers need to understand the correlations and feedback between the design variables and lifecycle parameters to make optimal decisions. A framework is proposed for the high level integration of design, component degradation, and maintenance decisions. The framework includes constructing screening models for rapid design evaluation, defining a multi-objective robust optimization problem, and using sensitivity studies to compare trade-offs between different design and maintenance strategies. A case example of power plant condenser is used to illustrate the proposed framework and advise how designers can make informed comparisons between different design concepts and maintenance strategies under highly uncertain lifecycle conditions.
An Approach to Design Rationale Retrieval Using Ontology-Aided Indexing
Authors: Li Luye , Qin Feiwei , Gao Shuming
Published: February 2014

Design rationale is an important category of design knowledge. Effective reuse of design rationale depends on its successful retrieval. In this paper, an approach to design rationale retrieval using ontology-aided indexing is presented. First, a design rationale ontology is designed based on the extended IBIS-based design rationale representation. Then, an ontology-aided indexing method is given to build indices for design rationale records. Furthermore, three kinds of query modes are developed to support flexible querying. Finally, a prototype system is implemented. The experimental results show the effectiveness of the proposed approach.
Function-to-Form Mapping in Design Synthesis Taking Sustainable Manufacturing Issues Into Consideration
Authors: Li Yunpeng , Roy Utpal
Published: February 2014

The function-to-form (F-T-F) mapping methodology provides a generic reasoning mechanism used in early design synthesis process to help designer map functional requirements of a product to a physical form (product) by optimally composing a set of pre-defined artifacts to satisfy the given physical constraints and design goals. The objective of this paper is to develop an integrated function-to-form technique that incorporates environmental constraints and other sustainable manufacturing issues into a previous function-to-form mapping framework. Since sustainability is considered as a global constraint for any product, a top-down design strategy and an assembly-centric product representation are needed for the product’s global evaluation and optimization. In this paper, it is proposed to integrate the Design for Manufacturing and Assembly (DFMA) and Life Cycle Assessment (LCA) techniques into the function-to-form mapping framework for considering the assemblability, manufacturability and other issues related to the product’s environmental impacts in its early design stage. A case study has been presented as a proof-of-concept of the proposed methodology.
Bringing User Experience (UX) Upstream to Design: A Sensing Based Approach
Authors: Bordegoni Monica , Cugini Umberto
Published: February 2014

Several studies in the field of Emotional Engineering have focused on studying new methods to design products that elicit positive emotions in the future consumers, focusing on the study of the visual perception of the products. A typical application of Emotional Engineering (E-E) is in the product design domain, where the design of new products tends to be validated even with respect to emotional responses, well before releasing the final product design. This paper proposes a new method and process for product design that is driven by the validation of emotional aspects, elicited by multi-sensory experience with products, more in line with the E-E perspective.
Proposition of Combined Approach for Architecture Generation Integrating Component Placement Optimization
Authors: Moullec Marie-Lise , Jankovic Marija , Bouissou Marc , Bocquet Jean-Claude , Maas Olivier
Published: February 2014

Architecture generation and evaluation are critical points in complex systems design. System architecting starts with the exploration of a set of potential solutions that is progressively focused towards the most promising ones. In theory, these solutions are identified through their potential ability to reach system requirements. However, in early design stages, data supporting design choices are fuzzy and uncertain, making difficult the evaluation a priori of the future system architecture performance. In this paper, we propose a method using Bayesian Networks (BN) and Constraint Satisfaction Problem (CSP) to first generate potential system architectures, and then select the best ones regarding system requirements. The association of these two approaches allows to enhance architecture evaluation through integration of component placement optimization. This approach is demonstrated and implemented in radar antenna architecture generation. In the end, we also discuss some of the limits of the proposed approach as well as future research directions.
An Approach for Managing Engineering Changes in Product Families
Authors: Raffaeli Roberto , Malatesta Marco , Marilungo Eugenia , Germani Michele
Published: February 2014

Product development is characterized by continuous updating of existing solutions in order to cope with new market requirements. Families of product variants are used to satisfy the needs of new potential customers and penetrate new market niches.

New requirements impact on the structure of a product to be changed and also on the other instances of the family which share common parts. Several change management approaches have been proposed in the literature but they are limited to analysis of a single product instance.

This paper proposes a dependency-based change propagation approach which is able to cope with engineering changes extended to product families. The proposed tool is based on a multilevel representation of the product structure, where functions, modules and physical parts are defined and interrelated. This system allows evaluating the consequences of engineering changes introduced in the family structure and computing indices of the impact on several design for X contexts.

The tool was tested within the R&D department of a large sized company producing household appliances. Gather data are presented and analyzed to identify potentialities and shortcomings of the approach.
On-Line Thermal Control for Injection Moulding Process
Authors: Seo Jaho , Khajepour Amir , Huissoon Jan P. , Park Young-Jun
Published: February 2014

Thermal control is a key issue for injection moulding process due to its effects on production quality and rate. In this study, an on-line thermal control strategy is provided for effective thermal management in plastic injection moulding process. The strategy covers for methods in determining sensor locations as a prerequisite step for modeling and control, identifying a thermal dynamic model of a mould with uncertainties and designing a cavity wall temperature controller. A verification of the designed controller’s performance is carried out from the viewpoints of accuracy in on-line temperature tacking and response time under different injection moulding process with various cycle-times.
Using Rigid-Body Mechanism Topologies to Design Shape-Changing Compliant Mechanisms
Authors: Zhao Kai , Schmiedeler James P.
Published: February 2014

This paper uses rigid-body mechanism topologies to synthesize distributed compliant mechanisms that approximate a shape change defined by a set of morphing curves in different positions. A single-actuator compliant mechanism is synthesized from a single degree-of-freedom rigid-body mechanism’s base topology in one of two ways. In one case, the base topology is directly evaluated through dimensional synthesis to determine the compliant mechanism’s optimal dimensions. In the second, the base topology establishes an initial element network for an optimization routine that determines topologies and dimensions simultaneously, and an improved design domain parameterization scheme ensures that only topologies with well-connected structures are evaluated. A multi-objective genetic algorithm is employed to search the design space, and the deformation is evaluated using geometrically nonlinear finite element analysis. The procedure’s utility is demonstrated with two practical examples — one approximating open-curve profiles of an adaptive antenna and the other closed-curve profiles of a morphing wing.
Proposal of an Activity-Based Adaptive Process Model for Innovative Design
Authors: Zhang Qiang , Deniaud Ioana , Baron Claude , Caillaud Emmanuel
Published: February 2014

In this paper, we introduced an activity-based adaptive process model that views innovative design as a complex adaptive system. Instead of predefining the process architecture, we constructed the model framework by adaptively selecting the design activity by the activity value. We defined the activity value as the complexity reduction associated with the possibility of satisfying the design targets and design stages. Moreover, this paper contributes an expert evaluation methodology to evaluate the activity value in order to balance innovation and control. Finally, we applied the model to an industrial case and analyzed the simulation results.
Early Developments of a Parallelly Actuated Humanoid, SAFFiR
Authors: Lahr Derek , Orekhov Viktor , Lee Bryce , Hong Dennis
Published: February 2014

This paper presents the design of our new 33 degree of freedom full size humanoid robot, SAFFiR (Shipboard Autonomous Fire Fighting Robot). The goal of this research project is to realize a high performance mixed force and position controlled robot with parallel actuation. The robot has two 6 DOF legs and arms, a waist, neck, and 3 DOF hands/fingers. The design is characterized by a central lightweight skeleton actuated with modular ballscrew driven force controllable linear actuators arranged in a parallel fashion around the joints. Sensory feedback on board the robot includes an inertial measurement unit, force and position output of each actuator, as well as 6 axis force/torque measurements from the feet. The lower body of the robot has been fabricated and a rudimentary walking algorithm implemented while the upper body fabrication is completed. Preliminary walking experiments show that parallel actuation successfully minimizes the loads through individual actuators.
Concurrent Design of Functional Reliability and Failure Prognosis for Engineered Resilience
Authors: Wang Pingfeng , Youn Byeng D. , Hu Chao
Published: February 2014

This paper presents a new system design platform and approaches leading to the development of resilient engineered systems through integrating design of system functions and prognosis of function failures in a unified design framework. Failure prognosis plays an increasingly important role in complex engineered systems since it detects, diagnoses, and predicts the system-wide effects of adverse events, therefore enables a proactive approach to deal with system failures at the life cycle use phase. However, prognosis of system functional failures has been largely neglected in the past at early system design stage, mainly because quantitative analysis of failure prognosis in the early system design stage is far more challenging than these activities themselves that have been mainly carried out at the use phase of a system life cycle. In this paper, a generic mathematical formula of resilience and predictive resilience analysis will be introduced, which offers a unique way to consider lifecycle use phase failure prognosis in the early system design stage and to systematically analyze their costs and benefits, so that it can be integrated with system function designs concurrently to generate better overall system designs. Engineering design case studies will be used to demonstrate the proposed design for resilience methodology.
Probabilistic Design of Smart Sensing Functions for Structural Health Monitoring and Prognosis
Authors: Almaktoom Abdulaziz T. , Wang Zequn , Wang Pingfeng
Published: February 2014

Significant technological advances in sensing and communication promote the use of large sensor networks to monitor structural systems, identify damages, and quantify damage levels. Prognostics and health management (PHM) technique has been developed and applied for a variety of safety-critical engineering structures, given the critical needs of the structure health state awareness. The PHM performance highly relies on real-time sensory signals which convey the structural health relevant information. Designing an optimal structural sensor network (SN) with high detectability is thus of great importance to the PHM performance. This paper proposes a generic SN design framework using a detectability measure while accounting for uncertainties in material properties and geometric tolerances. Detectability is defined to quantify the performance of a given SN. Then, detectability analysis will be developed based on structural simulations and health state classification. Finally, the generic SN design framework can be formulated as a mixed integer nonlinear programming (MINLP) using the detectability measure and genetic algorithms (GAs) will be employed to solve the SN design optimization problem. A power transformer study will be used to demonstrate the feasibility of the proposed generic SN design methodology.
Design of a Robust Classification Fusion Platform for Structural Health Diagnostics
Authors: Tamilselvan Prasanna , Wang Pingfeng , Hu Chao
Published: February 2014

Efficient health diagnostics provides benefits such as improved safety, improved reliability, and reduced costs for the operation and maintenance of engineered systems. This paper presents a multi-attribute classification fusion approach which leverages the strengths provided by multiple membership classifiers to form a robust classification model for structural health diagnostics. Health diagnosis using the developed approach consists of three primary steps: (i) fusion formulation using a k-fold cross validation model; (ii) diagnostics with multiple multi-attribute classifiers as member algorithms; and (iii) classification fusion through a weighted majority voting with dominance system. State-of-the-art classification techniques from three broad categories (i.e., supervised learning, unsupervised learning, and statistical inference) were employed as the member algorithms. The proposed classification fusion approach is demonstrated with a bearing health diagnostics problem. Case study results indicated that the proposed approach outperforms any stand-alone member algorithm with better diagnostic accuracy and robustness.
Space- and Time-Fractional Legendre-Pearson Diffusion Equation
Authors: Klimek Malgorzata , Agrawal Om Prakash
Published: February 2014

In this paper we study space- and time-fractional diffusion equations called Fractional Legendre-Pearson Diffusion Equations (FLPDEs) in finite space interval. We define the space fractional part using Fractional Legendre Operators and the time fractional part using Fractional Caputo derivative. We consider both the standard and symmetrized versions of FLPDEs. For both equations, we use the method of integral Legendre transform and inverse integral Legendre transform to solve the two equations. The solutions are given in the form of infinite series containing Legendre polynomials dependent on the space variable and Mittag-Leffler functions dependent on time. We demonstrate that these series are convergent. The simplicity with which the solutions of the FLPDEs are obtained in closed form should initiate further research in this field.
Value Chain Simulation and Analysis Methods to Design Recycling Systems
Authors: Farel Romain , Yannou Bernard
Published: February 2014

Creating a new recycling system generally suffers from the lack of a coordinated group of stakeholders rather than technical issues of treatment, or available recyclable deposit. Value chain concept and methods has assumed a dominant position in studying industry from management and coordination point of view. Decision support methods using value chain require the acquisition of data from various existing corporate databases or data warehouses. As an effort in developing a methodology and in result of conducting a national industrial recycling chain in France, this study proposes a general value chain design approach which provides a new direction for research and application of value chain from scratch for multi-stakeholder industrial systems. This paper introduces value chain design as a way to determine, model, and analyze and evaluate the industrial ecosystems, in order to generate future scenarios and provide evaluation criteria for decision makers.
A Library of Feature Fitting Algorithms for GD&T Verification of Planar and Cylindrical Features
Authors: Mohan Prashant , Shah Jami , Davidson Joseph K.
Published: February 2014

Conformation of a manufactured feature to the applied geometric tolerances is done by analyzing the point cloud that is measured on the feature. To that end, a geometric feature is fitted to the point cloud and the results are assessed to see whether the fitted features lies within the specified tolerance limits or not. Coordinate Measuring Machines (CMMs) use feature fitting algorithms that incorporate least square estimates as a basis for obtaining minimum, maximum, and zone fits. However, a comprehensive set of algorithms addressing the fitting procedure (all datums, targets) for every tolerance class is not available. Therefore, a Library of algorithms is developed to aid the process of feature fitting, and tolerance verification. This paper addresses linear, planar, circular, and cylindrical features only. This set of algorithms described conforms to the international Standards for GD&T.

In order to reduce the number of points to be analyzed, and to identify the possible candidate points for linear, circular and planar features, 2D and 3D convex hulls are used. For minimum, maximum, and Chebyshev cylinders, geometric search algorithms are used. Algorithms are divided into three major categories: least square, unconstrained, and constrained fits. Primary datums require one sided unconstrained fits for their verification. Secondary datums require one sided constrained fits for their verification. For size and other tolerance verifications we require both unconstrained and constrained fits.