bluuebunny/crossref_metadata_2025 huggingface dataset:
Organisational Obstacles and Pitfalls on the Road to Product Data Management: Findings From a Longitudinal Study
Authors: Waterson P. E. , Pepper K. , Clegg C. W. , Fagan C.
Published: November 2020

In this paper we describe the findings of a longitudinal study of the implementation, adoption and early use of a set of Product Data Management (PDM) tools. The findings are based on research carried out within a major engineering company located in the UK. Our findings highlight a number of key issues that proved to be problematic during, and after the tools had been introduced. These issues include the management and coordination between all groups involved in the change (i.e., technical, implementation and end user groups); problems with training and education; and, planning for changes which are likely to happen to established working practices. The paper concludes with a set of recommendations and key lessons learnt from the study.
Strategic Product Planning: The Development of Products and Markets of Tomorrow As an Entrepreneurial Challenge
Authors: Gausemeier Jürgen , Binger Volker
Published: November 2020

The identification of the products and markets of tomorrow is a challenging entrepreneurial task to be achieved by Strategic Product Planning. The following presentation shows a way of emphasising Strategic Product Planning more strongly as the first cycle in the product development process and of embedding it into the complete process. This consists of the task areas of determination of potential & product, business planning and product creation. The method of scenario-management presented here enables the enterprise to plan the future. Based on developed future scenarios for markets and wide company areas, it is possible to determine the potential success — and dangers — for the established business at a very early stage [GF99].

In this presentation, the scenario-method will be introduced as a means to support strategic product planning by using the example of the development of future scenarios for the automotive industry. The future concept will contain the higher interaction of future market requirements (Market Pull) and possible technology potentials (Technology Push).
Distributed Modeling in Engineering: Towards a Tool-Supported Integration of Notations Using Meta Object Facilities
Authors: Jesko Dirk , Paul Georg
Published: November 2020

The development of modern products is characterized by the participation of multiple developers from different domains. Further, the development is usually distributed over different companies. One characteristic that derives from this heterogenous environment is the application of different methods, notations, and software tools during the development process. Although many tasks are supported by software, especially modeling tools lack a support for using different notation and the independent specification of development artifacts. In this paper we will describe an approach for the integration of different notations using a metamodel based on the Meta Object Facilities (MOF). The independent specification of system artifacts is thereby achieved by applying the ViewPoint framework. The main focus of the paper is the discussion of defining the concepts of the ViewPoint framework within a metamodeling architecture. Further, the overall structure of the metamodel will be described. Finally, the components of a software system supporting the management of the metamodel and the actual development using ViewPoints is presented.
A Socio-Technical Approach to Knowledge Capture, Sharing and Reuse in Aerospace Design
Authors: Kerr M. P. , Waterson P. E. , Clegg C. W.
Published: November 2020

This paper describes the first phase of a study of knowledge management in design from a multi-disciplinary perspective, using a socio-technical approach. The prime objective is to understand the human, social, organisational and technological aspects of current knowledge capture, sharing and reuse activities. Designers from a range of contexts, across two aerospace companies, were interviewed about the details of a design episode they had been personally involved in. They focussed on the critical problems encountered and potential solutions. This resulted in the specification of a set of social and technical requirements for the overall work system. These requirements are then discussed in terms of their implications of human/machine allocation and use in the development of a future vision for design. The paper concludes by looking forward to the next phase of the project. Here the objective is to build a technological tool to support designers in their day-today activities and to incorporate social requirements for the overall system of knowledge management.
Prediction and Diagnosis of Propagated Errors in Assembly Systems Using Virtual Factories
Authors: Baydar Cem M. , Saitou Kazuhiro
Published: November 2020

Large-scale automated assembly systems are widely used in automotive, aerospace and consumer electronics industries to obtain high quality products in less time. However, one disadvantage of these automated systems is they are composed of so many working parameters. Since it is not possible to monitor all these parameters during the assembly process, an undetected error may propagate and result in a more critical detected error. Anticipation of these types of failures is limited to human experts prior to the assembly operation. In this paper, a unique way of detecting and diagnosing these types of failures by using Virtual Factories is discussed. A Virtual Factory is developed by building and linking several software modules to predict and diagnose propagated errors. A multi-station assembly system is modeled and a previously discussed “off-line prediction and recovery” method was applied. The obtained results showed that this method is capable of predicting propagated errors and it is efficient to diagnose even the failure case is too complex to solve for a human expert.
Analysis of the Robotic Assembling Accuracy Based on Virtual Assembly Environment
Authors: Zhang Zheng , Luo Xuebuo , Xie Cunxi
Published: November 2020

Multi-degree freedom robots have many advantages including agility, heavy-loading capability and high flexibility. They play a very important role in mechanical assembly. Due to the complexity of their spatial pose, the robot assembling accuracy analysis should not be confined to the 2-D plane.

This paper applies the accuracy analysis to the virtual environment by constructing accurate models of robot assembly unit such as 3-D geometrical modeling, physical modeling, and behavioral modeling. Using the interactive and 3-D graphical environment to observe and evaluate the effects of assembling process. By operating the virtual 3-D model of the robot assembly unit and simulating the assembling process in the virtual assembly environment, the influence of errors in assembly can be analyzed and the statistical value of errors can be obtained. This paper also presents the method of visualization in analyzing the robot assembling accuracy, and studies the influence of spatial pose of robot assembly on the axis-hole assembly success rate, especially the robot teaching accuracy. Through the integration of the various errors and on the basis of the assembling accuracy, the tolerance of error source can be reasonably distributed to meet the requirement for assembling accuracy, and the planning of robot assembly unit can be improved.
A Region Based Approach to Automated Design of Multi-Piece Molds With Application to Rapid Tooling
Authors: Chen Yong , Rosen David
Published: November 2020

Rapid Tooling and multi-piece molds can dramatically reduce the lead-time for injection molded prototypes. A systematic approach based on regions is developed for automated design of multi-piece Rapid Tooling molds. Regions are connected collections of part faces that can be formed by one mold piece. This paper first formulates a linear programming problem for finding a satisfactory parting direction of a region. An approach to detect non-drafted and under-drafted faces during determination of parting direction is presented. An algorithm and related data representations are presented for the region combining process, intended to minimize the number of regions and, hence, mold pieces. Finally a test example and two industrial examples are provided which illustrate the effectiveness of the developed approach.
Virtual Prototyping Based Design Optimization of PEM Fuel Cell Gas Delivery Plates
Authors: Zheng Rong , Dong Zuomin
Published: November 2020

Gas delivery plates are key components for a Proton Exchange Membrane (PEM) fuel cell. The unique functions of these plates impose special requirements on their strength, conductivity and electro-chemistry stability. Cost reduction of these plates can greatly facilities the commercialization of PEM fuel cell, the promising zero emission power plant for the future. In this work, a virtual prototyping study on PEM fuel cell gas delivery plate is carried out. Solid modeling and mathematical modeling are used to form virtual prototypes of the gas delivery plates. Computational fluid dynamic (CFD) analysis and nonlinear finite element analysis (FEA) on plate structure and flow field properties are used to test the performance of the designed plates and to guide the design optimization. The research focuses on the new fuel cell plate designs that use polymer composite material to form flow field channels. The method of virtual prototyping based design optimization is discussed using a real fuel cell plate design example. This study provides guidelines to fuel cell plate development and demonstrates a new design approach.
Application of Vague Geometric Representation for Shape Instance Generation of the Human Body
Authors: Moes Niels C. C. M. , Rusák Zoltán , Horváth Imre
Published: November 2020

The objective of this research is the development of a generic model for the shape of a part of the human body. A generated instance is intended to be used in the construction of a Finite Elements model. The selected product type is a sitting support. With the help of a multiple regression model the shape of the upper leg and the buttock area are statistically described.

The predictive variables for this shape generation are specific human body characteristics, which are uncertain and usually incomplete. The actual model is a vague domain defined by a set of intersection points on the distribution vectors.

The measurements of the shape and specific characteristic landmarks were done with the Microscribe scanning device and the mirror box.

The results include (i) a statistical analysis of the measured subject properties, (ii) the generation of the inner closure, the outer closure, and the corresponding distribution vectors, (iii) the location indices on the distribution vectors, (iv) the statistical model to generate instances.
A Skeletal Topological Modeler Based on Bounding Spheres
Authors: Thompson David , Crawford Richard
Published: November 2020

Solid modelers are most frequently used when the final shape of the object to be modeled is known. One reason for this is the amount of input required on the part of designers to create even simple models. We propose a modeler requiring only weighted points to be specified. The connectivity of the points is determined based on proximity and the value of the weight at each point. The connected diagram — a subcomplex of the regular triangulation of the input points known as an alpha shape — serves as a skeleton for an offset surface which becomes the solid model. Functional representations of a design might also be attached to the skeleton as well.
The Geometric Principle of Automatic Modular Fixture Planning
Authors: Wu Yuguang , Gao Shuming , Chen Zichen
Published: November 2020

In this paper, we present a systematic methodology for automatic planning of modular fixture. The approach constructs all the feasible fixture plans of a part with linear and circular edges by using the mechanism theory. Based on the geometric relationships between locator triplet and three boundary edges of a part, we classified the loading and unloading motion of the part into two kinds, i.e. translational motion and rotational motion. Moreover we put forward the notions of the locator visible cone and the pivotal locator, and utilize these notions to analyze the accessibility of locators. To effectively analyze the feasibility of clamping the part, and generate all of the feasible clamp positions, the notions of the triangle of instant rotational center and the same direction edge of the triangle are set forth and utilized. Finally, several criteria of evaluating fixture design are given for generating optimal fixture plan.
Swirl Distribution Effects on the Thermal Characteristics of Premixed Flames
Authors: Archer Sean , Gupta Ashwani K.
Published: November 2020

An experimental investigation has been carried out on four premixed flames using a double concentric swirl burner. The influence of radial distribution of swirl on the global flame behavior, thermal and emission characteristics have been determined. Temperature data was compensated with time constant data to generate mean and fluctuating temperature maps, probability density distributions of temperature, power spectra and thermal integral- and micro-time scales in the flames. Direct flame photographs were taken to archive flame shape and light intensity. These data provided valuable information for practical combustors on better swirl configurations. These configurations will depend heavily on the designed power settings. Contributed results directly from this investigation are for a lean premixed flame to achieve low emission and higher efficiency. The results reveal that in a counter-swirl configuration, the swirl strength in inner annulus should be greater than the outer annulus. However, for the co-swirl configuration it is more beneficial to have smaller swirl strength in the inner annulus than the outer annulus.

It is found that premixed flames can possess significant circumferential non-uniformities at all flow and operational conditions. Detailed data shows that the flame thermal field and temperature distribution is strongly related to its emissions. High NOx emission is found in flames where the integral time scales and the mean temperature are high in the presumed lower recirculation region. High CO formation is found in flames that have high integral time scales in the lower recirculation region but have a low mean temperature in this same region. Thermal time scales provide important information on the thermal and emission characteristics of premixed flames.
On the Aggregation of Preferences in Engineering Design
Authors: Allen Beth
Published: November 2020

This paper considers the possibility for aggregation of preferences in engineering design. Arrow’s Impossibility Theorem applies to the aggregation of individuals’ (ordinal) preferences defined over a finite number of alternative designs. However, when the design space is infinite and when all individuals have monotone preferences or have von Neumann-Morgenstern (cardinal) utilities defined over lotteries, possibility results are available. Alternative axiomatic frameworks lead to additional aggregation procedures for cardinal utilities. For these results about collaborative design, aggregation occurs with respect to decision makers and not attributes, although some of the possibility results preserve additive separability in attributes.
Topology Optimization of Compliant Mechanisms With Strength Considerations
Authors: Saxena Anupam , Ananthasuresh G. K.
Published: November 2020

Multi-criteria formulations reported previously in topology design of compliant mechanisms address the flexibility and stiffness issues simultaneously and aim at attaining an optimal balance between these two conflicting attributes. Such techniques are successful in indirectly controlling the local stress levels by constraining the input displacement. Individual control on the conflicting objectives is often difficult to achieve with these flexible and stiff formulations. Resultant topologies may sometimes be overly stiff and there is no guarantee for design against failure as local stresses may exceed the permissible yield strength of the constituting material. In this paper, local failure conditions via stress constraints are incorporated in topology optimization algorithms to obtain compliant and strong designs. Quality functions are employed to impose stress constraints on retained material ignoring non-existing regions in the design domain. Stress constraints are further relaxed to regularize the design space to help the KKT conditions-based mathematical programming algorithms yield improved solutions. Examples are solved to corroborate the solutions for failure-free compliant topologies that are much improved than those obtained using flexible and stiff multi-criteria objectives.
Some Preliminary Results on the Development and Comparison of a New Multi-Objective Genetic Algorithm
Authors: Farhang-Mehr A. , Wu J. , Azarm S.
Published: November 2020

Some preliminary results for a new multi-objective genetic algorithm (MOGA) are presented. This new algorithm aims at obtaining the fullest possible representation of observed Pareto solutions to a multi-objective optimization problem. The algorithm, hereafter called entropy-based MOGA (or E-MOGA), is based on an application of the concepts from the statistical theory of gases to a MOGA. A few set quality metrics are introduced and used for a comparison of the E-MOGA to a previously published MOGA. Due to the stochastic nature of the MOGA, confidence intervals with a 95% confidence level are calculated for the quality metrics based on the randomness in the initial population. An engineering example, namely the design of a speed reducer is used to demonstrate the performance of E-MOGA when compared to the previous MOGA.
An Integrated Framework for 3D Tolerance Chains in Design and Manufacturing
Authors: Ballot Eric , Bourdet Pierre
Published: November 2020

This paper is about a new model of geometric deviation to compute tridimensional tolerance chains. By the use of a simplification of geometric deviation well adapted to computation of tolerances, we will show how to compute systematically the consequences of geometric deviation from functional requirements to manufacturing. Under the hypothesis that geometric deviations lead only to small displacement of parts, we will demonstrate how their propagation can be computed. We will highlight the improvement yielded by the proposed model and the consequences on the description of tolerances and manufacturing.
A CAD Methodology for Concurrent Design of a Fuel Tank Lid
Authors: Carfagni Monica , Landi Luca
Published: November 2020

A CAD procedure has been developed to reduce lead times and development costs in the design of automobile components. The associative parametric capability of a CAD platform were applied to the design of a fuel tank lid. It comprises five macro phases: acquisition of the standards, definition of the main functional design constraints, implementation of a hardcopy design flow, transposition on the CAD platform and validation of the design flow. In this paper the first four topics will be discussed focussing on design functional constraints. The procedure is readily applicable to a vast number of complex components.
A Family of 3-DOF Translational Parallel Manipulators
Authors: Carricato Marco , Parenti-Castelli Vincenzo
Published: November 2020

This article addresses parallel manipulators with fewer than six degrees of freedom, whose employ may prove valuable in those applications in which a higher mobility is uncalled-for. In particular, a family of 3-dof manipulators containing only revolute joints or at the most revolute and prismatic ones is studied. Design and assembly conditions sufficient to provide the travelling platform with a pure translational motion are determined and two sub-families that fulfill the imposed constraint are found: one is already known in the literature, whilst the other is original. The new architecture does not exhibit rotation singularities, i.e. configurations in which the platform gains rotational degrees of freedom. A geometric interpretation of the translation singularities is provided.
Hybrid Analysis Method for Reliability-Based Design Optimization
Authors: Choi Kyung K. , Youn Byeng D.
Published: November 2020

Reliability-Based Design Optimization (RBDO) involves evaluation of probabilistic constraints, which can be done in two different ways, the Reliability Index Approach (RIA) and the Performance Measure Approach (PMA). It has been reported in the literature that RIA yields instability for some problems but PMA is robust and efficient in identifying a probabilistic failure mode in the RBDO process. However, several examples of numerical tests of PMA have also shown instability and inefficiency in the RBDO process if the Advanced Mean Value (AMV) method, which is a numerical tool for probabilistic constraint evaluation in PMA, is used, since it behaves poorly for a concave performance function, even though it is effective for a convex performance function.

To overcome difficulties of the AMV method, the Conjugate Mean Value (CMV) method is proposed in this paper for the concave performance function in PMA. However, since the CMV method exhibits the slow rate of convergence for the convex function, it is selectively used for concave-type constraints. That is, once the type of the performance function is identified, either the AMV method or the CMV method can be adaptively used for PMA during the RBDO iteration to evaluate probabilistic constraints effectively. This is referred to as the Hybrid Mean Value (HMV) method.

The enhanced PMA with the HMV method is compared to RIA for effective evaluation of probabilistic constraints in the RBDO process. It is shown that PMA with a spherical equality constraint is easier to solve than RIA with a complicated equality constraint in estimating the probabilistic constraint in the RBDO process.
Mobility Analysis of RSSR Mechanisms by Working Volume
Authors: Chung Wen-Yeuan
Published: November 2020

An RSSR mechanism is analyzed by treating the linkage as two manipulators. The mobility region of the input link or the output link is found from the intersection region of the working volumes generated by both manipulators. By analyzing the intersection region on either the plane of the input link or the output link, the mobility region can then be calculated from the intersection of an ellipse and a unit circle. Concise discriminants and flowcharts are proposed to determine the type for several special RSSR linkages, such as spherical four-bar and simply skew four-bar. Grashof’s rule is also derived for planar four-bar linkages.
Towards a Framework for Acquisition of Design Knowledge
Authors: Dzbor Martin , Zdrahal Zdenek
Published: November 2020

Engineering design is a knowledge-intensive process driven by various design objectives. Design is an iterative process where the objectives evolve together with the solutions in order to deliver an artefact with the desired properties and functions. Many design theories developed so far suggest more or less efficient ways for finding a suitable solution to the given goals. However, they often leave open the issue of ‘solution talkback’. Discovery of new design objectives and amendment of the existing ones is as important as the development of design solutions. The biggest issue with solution talkback is the presence of tacit knowledge in addition to the explicit one. This paper draws on a theory that incorporates some typical features of design problems, and transfers theoretical findings about reflection on the design actions to a tool for acquisition of design knowledge. First, key terms are defined and theoretical framework is introduced. Afterwards we look at the means for capturing explicit and tacit design knowledge more in depth.
A Comparison of Polynomial Based Regression Models in Vehicle Safety Analysis
Authors: Gu Lei
Published: November 2020

Vehicle crash is a highly nonlinear event in terms of the structural and dummy responses. However, Linear and quadratic polynomials regression are still widely used in the design optimization and reliability based optimization of vehicle safety analysis. This paper investigates the polynomial based subset selection regression models for vehicle safety analysis. Three subset selection techniques: all possible subset with linear polynomial, stepwise with quadratic polynomial and sequential replacement with quadratic and cubic polynomials, are discussed. The methods have been applied to data from finite element simulations of vehicle full frontal crash, side impact and frontal offset impact. It is shown subset selection with sequential replacement algorithm gives the best accuracy responses. It is also shown from limited finite element simulation data, the quadratic polynomial is good enough for most structural and dummy responses when gauges and materials are used as design variables. For vehicle weight, linear polynomial fits well.
An Efficient Algorithm for Circular Blending of Edges
Authors: Jaiswal Sharad K. , Ghosal A. , Gurumoorthy B.
Published: November 2020

This paper describes a method for constructing circular blends using geometric tools. The algorithm presented in this paper is based on marching along a characteristic direction on the tangent plane to the Voronoi surface of the two surfaces being considered for blending. Starting from any point on the edge to be blended, the algorithm converges to the spine curve. The characteristic direction of marching lies on the plane containing the points in assignment and the tangent plane to the Voronoi surface. The spine curve generation algorithm presented in this paper, does not require computing offsets of surfaces or an explicit evaluation of surface-surface intersection (SSI). The algorithm presented is computationally simple and fast, and can be used for constant and variable radius circular blending of surfaces, each of which is G2 continuous. The algorithm can also be used to obtain the surface-surface intersection curve by setting the radius of blend to zero.
Solid Model Reconstruction of Wireframe CAD Models
Authors: Inoue Keisuke , Shimada Kenji , Chilaka Karthick
Published: November 2020

This paper describes an efficient method for reconstructing a solid model by generating its boundary surface from a wireframe model. This method utilizes a wireframe that is topologically a 2-connected planar multigraph, which can be interpreted as a solid in multiple ways. First the graph is decomposed using triconnected component decomposition; all solutions are then generated combinatorially. Each solution is a set of face loops representing a closed 2-manifold of genus 0. After giving a surface geometry for each face loop, the solutions are pruned according to prescribed geometric simplicity criteria. A method for extending the algorithm to deal with general disconnected wireframes is also described. This approach is characterized by not using geometry for reconstructing 2-manifold topology; geometry is used for discarding geometrically invalid solutions and prioritizing remaining ones. Therefore, negative influence of geometric errors is minimized and even wireframes having incomplete geometry can be handled. The algorithm provides an easy and intuitive method of geometric modeling as well as a conversion tool for existing wireframes.
Alternate Sampling Methods for Use With Multidisciplinary Design Optimization in a High Performance Computing Environment
Authors: Kodiyalam Srinivas , Sobieszczanski-Sobieski Jaroslaw
Published: November 2020

The focus of this paper on investigation of alternate methods for sampling the design space for use with MDO solutions in a multi-processor, high performance computing environment. The primary aim of these methods is to maximize the information gathered about the design space of interest. The conceptual simplicity of the MDO approach described in this paper is paid for by the large computing labor in the sampling. That labor is effectively compressed in time by the HPC environment that operates a large number of processors concurrently.
Discrete Curvature Approximations for the Segmentation of Polyhedral Surfaces
Authors: Lesage D. , Léon J.-C. , Véron P.
Published: November 2020

The segmentation of digitized data to decompose a free form surface into patches is one of the key processes used to perform the reverse engineering of an object. To this end, discrete curvature approximations are introduced that form the basis of a segmentation process which lead to a decomposition of digitized data into areas that will help the construction of surface patches.

The approach presented relies on the use of a polyhedral representation of an object built from the digitized data input. Then, it is shown how noise reduction techniques, edge swapping techniques and adapted remeshing schemes can participate to different preparation phases which provide a geometry that highlights useful characteristics for the segmentation process.

The segmentation process is performed with various approximations of discrete curvatures evaluated on the polyhedrons issued by the preparation phases. The segmentation process proposed involves two stages: the identification of characteristic polylines and the identification of polyhedral regions. Discrete curvature criteria are adapted to each stage and concepts of invariant are introduced to generate criteria, which are constant over equivalent meshes. An outline of the segmentation procedure is provided together with examples of results for free form objects.
An Approach to Robust Design Employing Computer Experiments
Authors: Lee Jinkoo , Li D. J. , Liu Xiaoping , Soderborg Nathan , Sudjianto Agus , Vora Mahesh , Wang Steve C.
Published: November 2020

The importance of robust design has been well recognized throughout the industry. However, the cost and lead-time associated with hardware experiments are the obstacles to more applications of robust design methodology. Responding to the current trend of employing more computer experiments, we present an analytical robust design methodology based on computer experiments and three application examples from the automotive industry.
On the Classification of Fitting Problems for Single Patch Free-Form Surfaces in Reverse Engineering
Authors: Shalaby Mohammed M. , Nassef Ashraf O. , Metwalli Sayed M.
Published: November 2020

The design and manufacture of free-form surfaces increased in industrial applications, especially for the re-manufacture of spare parts, or in the die and mold industry. Reverse engineering has become the status quo technique in reproducing parts whose original designs are no longer existing or for parts, which assume slightly different shapes after manufacturing as in the case of die and mold industry. Laser scanners have been used extensively in sampling points from parts surfaces. The sampled points are then fitted with a free-form surface using one of the geometric modeling techniques such as Bezier or B-Spline surfaces. Since Non-Uniform Rational B-Splines (NURBS) is the most general form of geometric modeling techniques, this paper presents the possible formulations of the fitting problem optimization and presents some guidelines of the choice of the independent NURBS parameters, once the control points are evaluated using least squares fitting. The work shows that the use of NURBS weights can provide better improvements for the significant reduction of the fitting error, rather than the widely used knot values. In addition the work shows that parts with semi planar surfaces do not need further refinement using non-linear optimization methods.
Optimal Integration of Smart Actuators in Parallel and Cooperating Robots to Enhance Operating Speed and Accuracy
Authors: Yuan L. , Rastegar J.
Published: November 2020

Robot manipulators with parallel kinematics chains and two or more robots manipulating an object form closed kinematics chains. When revolute joints are used in the construction of such robotic manipulation systems, the presence of closed chains and their associated kinematics nonlinearity demands high harmonic motions in at least a number of the actuated joints. This is the case even if all the links are relatively rigid and attempt is made to synthesize the joint motions with minimal harmonic content. The presence of high harmonic components in the actuated joint motions is undesirable since as the operating speed is increased, their frequencies would rapidly increase and move beyond the dynamic response limitations of the actuating drives, thereby causing vibration and control problems. The performance of the system in terms of cycle time, tracking precision and the like would therefore suffer. This is particularly the case since the dynamics of such systems is also highly nonlinear and require higher harmonic components in the actuating torques (forces). In this paper, a systematic method is presented for optimal integration of smart (active) materials based actuators into the structure of cooperating robots and robot manipulators with parallel kinematics chain for the purpose of eliminating the high harmonic components of their actuated joint motions. As the result, the potential excitation of the natural modes of vibration of such systems and their related control problems can be greatly reduced. The resulting robotic systems should therefore be capable of operating at higher speeds with increased precision.
Implicit Uncertainty Propagation for Robust Collaborative Optimization
Authors: Gu Xiaoyu , Renaud John E.
Published: November 2020

In this research we develop a mathematical construct for estimating uncertainties within the bilevel optimization framework of collaborative optimization. The collaborative optimization strategy employs decomposition techniques that decouple analysis tools in order to facilitate disciplinary autonomy and parallel execution. To ensure consistency of the physical artifact being designed, interdisciplinary consistency constraints are introduced at the system level. These constraints implicitly enforce multidisciplinary consistency when satisfied. The decomposition employed in collaborative optimization prevents the use of explicit propagation techniques for estimating uncertainties of system performance. In this investigation we develop and evaluate an implicit method for estimating system performance uncertainties within the collaborative optimization framework. The methodology accounts for both the uncertainty associated with design inputs and the uncertainty of performance predictions from other disciplinary simulation tools.

These implicit uncertainty estimates are used as the basis for a new robust collaborative optimization (RCO) framework. The bilevel robust optimization strategy developed in this research provides for disciplinary autonomy in system design, while simultaneously accounting for performance uncertainties to ensure feasible robustness of the resulting system. The method is effective in locating a feasible robust optima in application studies involving a multidisciplinary aircraft concept sizing problem. The system-level consistency constraint formulation used in this investigation avoids the computational difficulties normally associated with convergence in collaborative optimization. The consistency constraints are formulated to have the inherent properties necessary for convergence of general non-convex problems when performing collaborative optimization.
Analysis of a Geometric Specification
Authors: Serré P. , Rivière A. , Duong A. N. , Ortuzar A.
Published: November 2020

This paper presents a series of methods for analyzing a geometric specification in 2 and 3 dimensional space. These are based on a new model for length and angle constraints as currently studied in variational geometry. These various tools will hopefully further the exchange of information between the designer and CAD systems.
Improving Commonality in Custom Products Using Product Platforms
Authors: Farrell Ronald S. , Simpson Timothy W.
Published: November 2020

Many companies find it difficult to maintain commonality and economies of scale in products with strict customer design requirements that may vary greatly from contract-to-contract or piece-to-piece. These strict and varied requirements typically result in highly customized products that are costly to manufacture, involve short production runs, and require long delivery times. In this paper we discuss how the strategic incorporation of product platforms into the design process can leverage the design effort of individually customized products. As an example, we discuss the design of yoke cross-section platforms used to mount valve actuators in the nuclear power industry. Through this example we demonstrate the process of creating a market segmentation grid, choosing a targeted segment, creating a product platform for the yoke cross-section, and defining the yoke product family. The proposed modular architecture for pattern construction reduces the number of new yoke patterns needed for manufacturing, which will generate the most significant savings. Implementation of the yoke platforms will also reduce design cycle time and costs, shorten quotation and lead times, and improve overall customer satisfaction and good will. The end result is a product platform design process that will improve response to customer requests, reduce design cost, and improve time to market for companies that make small production runs of highly customized products.
Path Verification for Unstructured Environments and Medical Applications
Authors: Stocco Leo J.
Published: November 2020

In some robot applications, workspace limitations can interfere with the desired path. In unstructured environments such as robot assisted surgery, checking for this must be done quickly to minimize procedural delays. Here, an algorithm is proposed that computes the distance between a few points on the desired path and the nearest workspace boundary to determine if the path is admissible (i.e. inside the dextrous workspace). Execution time is dependent on the proximity of the path to the reachable workspace limit and is upper bounded by a configurable workspace deadband value. The algorithm is applied to the ROBODOC® Surgical Assistant with good results.
Material Instrumentation: A Crystallization of Different Points of View in the Multi-Trade Product Design: A Visual and Tactile Field Application
Authors: Stoeltzlen N. , Minel S. , Bouchard C. , Millet D. , Aoussat A.
Published: November 2020

The topic of this article is to consider the role of material instrumentation in inter-trade cooperation and innovation dynamics. Within today’s competition context, innovation and knowledge management concern more and more products design. Various actors come into account during product design phase. We can quote designers, ergonomist, technologist and marketer: as many competence and different visions. In the first part, we will endeavour to show in what material instrumentation can stimulates the inter-trade cooperation. Then through a concrete example, we will endeavour to show how material instrumentation is supported by innovation.
Structural Synthesis of a Class of Five-DOF Parallel Robot Mechanisms Based on Single-Opened-Chain Units
Authors: Jin Qiong , Yang Ting-Li , Liu An-Xin , Shen Hui-Ping , Yao Fang-Hua
Published: November 2020

Based on the units of single-opened-chain limb, some topological characteristics of rank-degenerate parallel robot mechanisms are revealed, and a systematic methodology for the structural synthesis of a class of five degree-of-freedom parallel robot mechanisms is put forward in this paper. 49 new mechanisms with three translational and two rotational degrees of freedom are synthesized and classified. The method proposed in this paper is of universal significance and has been used for the structure synthesis of rank-degenerate parallel robot mechanisms with other kinematics output types.
Planned Experiments for Mechanical Assemblies
Authors: Sexton Christine J. , Lewis Susan M. , Please Colin P.
Published: November 2020

For experiments on mechanical products, conventional methods for reducing the experimental effort that is needed to extract information, such as those of Taguchi, can be infeasible because components with the dimensions needed for a standard factorial plan can be prohibitively expensive. Also, many factors for investigation are not directly measurable, as they are derived from the properties of several components and their assembly.

Methods are described for finding optimal plans for such experiments from a minimal sample of measured components, and are illustrated through a pilot investigation of a hydraulic pump.

Important issues are addressed of the robustness of the plans to possible missing data, for example due to product failure, and the need to ensure that the influences of the various different factors can be clearly extracted from the experimental results.

On-going work in the aeronautical industry on products for low-volume manufacturing is also described, where experiments are run on-line so that information can be swiftly obtained without delay in the manufacturing process.
Design for Control and Optimization of Flow Front Progression in Liquid Molding Processes
Authors: Kolavennu Soumitri , Foslien Wendy , Mathur Anoop , Parthasarathy Sanjay
Published: November 2020

The processing of composite materials has advanced from being a fine art to a well-studied science. The Advanced Materials Intelligent Processing Center (AMIPC) program demonstrates the use of process models, advanced technologies and data-centric algorithms to improve the quality and consistency of composites processing. As part of the AMIPC program, the Intelligent Process Control group at Honeywell developed a design environment for on-line control and disturbance rejection in Resin Transfer Molding process. In this paper we present a “design for control” methodology that proved to be a well suited for intelligent control of RTM processes. The major point addressed in this research is “Control issues need to be analyzed DURING process design”.
Design for Robustness of Modular Product Families for Current and Future Markets
Authors: Jiang Lan , Allada Venkat
Published: November 2020

This paper presents a modified Taguchi methodology to improve the robustness of modular product families against changes in customer requirements. The general research questions posed in this paper are: (1) How to effectively design a product family (PF) that is robust enough to accommodate future customer requirements? (2) How far into the future should the designers look to design a robust product family? An example of a simplified vacuum product family is used to illustrate our methodology. In the example, the customer requirements are selected as signal factors; the future changes of customer requirements are selected as noise factors; an index called the quality characteristic (QC) is set to evaluate the product vacuum family; and the module instance matrix (M) is selected as the control factor. Initially a relation between the objective function (QC) and the control factor (M) is established, and then the search space is systemically explored using the simplex method to determine the optimum M and the corresponding QC values. Next, various noise levels at different time points are introduced into the system. For each noise level, the optimal values of M and QC are computed and plotted on a QC-chart. The tunable time period of the control factor (in the example, the module matrix, M) is computed using the QC-chart. The tunable time period represents the maximum time for which a given module matrix can be used to satisfy the current and future customer needs. Finally, a robustness index is used to break up the tunable time period into suitable time periods that the designers should focus on while designing product families.
Cost-Specification Analysis: Design Concept Selection Based on Target Cost and Specifications
Authors: Takai Shun , Ishii Kosuke
Published: November 2020

This paper proposes a new system design methodology called the Cost-Specification Analysis. The method seeks to satisfy both target cost and required functionality simultaneously. The method assumes that the worth of a product’s structure such as a main system, a sub-system, an assembly and a part, or its specifications is proportional to its degree of contribution to fulfill the customer needs. The paper first presents systematic procedure to allocate the importance of the “Voice of the Customer” to product’s structures and their specifications. The Cost-Specification Analysis evaluates design concept candidates based on the target cost of a structure calculated from its worth, and the target specifications. The design concept that satisfies both the target cost and the specifications should lead to larger customer satisfaction and financially successful product. The design concept selection of a particle beam control system in linear accelerator serves as an illustrative example.
Assembly Quality Methodolgy: An Application of the Defect Prediction to Audio Equipment Assembled at Various Manufacturing Sites
Authors: Shibata Hirokazu , Cheldelin Brent , Ishii Kosuke
Published: November 2020

This paper describes the development of the quantitative predictor of defects that works not only on the whole product but also on its modular units. The authors divide the assembly process of a product into small modules, and apply the Assembly Quality Methodology (AQM) to determine the assembly complexity of the modules. The authors also verify the correlation between complexity factor of the modules and their defect rates. The newly proposed floating threshold assembly time improves the correlation between complexity factor and defects per unit (DPU). The authors discuss the comparison of case studies and the interpretation of their results for the future improvement of the method.
Environmentally Benign Manufacturing: Trends in Europe, Japan, and the USA
Authors: Allen Dave , Bauer Diana , Bras Bert , Gutowski Tim , Murphy Cindy , Piwonka Tom , Sheng Paul , Sutherland John , Thurston Deborah , Wolff Egon
Published: November 2020

In this paper, findings of the Panel for International Assessment of Environmentally Benign Manufacturing Technologies, sponsored by the United States National Science Foundation, are discussed. The mission of this interdisciplinary panel was to assess the international state-of-the-art in Environmentally Benign Manufacturing (EBM), and to identify priorities and collaborative opportunities. Over 50 sites in Japan, Europe and the United States were visited over the course of the yearlong study. This paper focuses on some global trends that were observed.
A Framework for Sufficiency Estimation of Engineering Design Models
Authors: Radhakrishnan Rajesh , McAdams Daniel A.
Published: November 2020

Engineering design models are aids that provide the designer with the ability to visualize the form and predict the nature and behavior of any product. In each stage of design, these models are used to predict the result of, or guide, design specifications, at a time when the design can still be changed with minimal negative impact. To ensure the downstream validity of these specifications or decisions, the designer must construct models that have sufficient accuracy and resolution.

Determining the goodness of a model for a particular design decision or specification is a fundamental and pervasive question in engineering. Though fast to construct, and generally inexpensive, models based on estimation and approximation may not provide information of sufficient quality to make an accurate evaluation. In contrast, the crispness and depth of information gained from detailed computational analysis or experimental trials may come at too great an expense.

Hence, a key aspect of model construction in design is deciding whether a model is appropriate for a particular design specification or evaluation considering accuracy and cost factors. This paper explores the application of utility theory to the model construction problem. We also discuss how estimated model accuracy affects the confidence of selecting a particular model. We present this research through application to a racecar sway bar.