bluuebunny/crossref_metadata_2025 huggingface dataset:
An Investigation Into Modeling and Solution Strategies for Optimal Design and Control
Authors: Reyer Julie A. , Papalambros Panos Y.
Published: December 2020

Combined optimal embodiment design and control is increasingly necessary in designing modern artifacts. Several strategies for achieving such a system-level optimum were examined previously in the context of a case study. Since different strategies often lead to different results, a more comprehensive understanding of the relative advantages and disadvantages of these “concurrent design” processes is desirable. The present article explores this question using a very simple problem to demonstrate the complexities involved. Monotonicity analysis and a decomposition framework help explain the reasons for arriving at different results, even unexpectedly. Conclusions are drawn regarding the effectiveness of the various modeling formulations.
Robust Concept Exploration in Engineering Design: Metamodeling Techniques and Goal Formulations
Authors: Lin Yao , Krishnapur Kiran , Allen Janet K. , Mistree Farrokh
Published: December 2020

In this paper we discuss the performance of different metamodeling techniques in Type II robust design. Five space-filling experimental designs and five correlation functions are compared in their capability for developing accurate kriging models. We observe that in our case study (a vehicle body), the orthogonal array is the best experimental design and the cubic correlation function is the best correlation function. Then the kriging models and response surface models for system response are determined and the solution obtained using compromise Decision Support Problem. We note that: 1) the goal formulation method of minimizing variance at the center point may be inappropriate in some situation, and 2) more robust solutions can be obtained with kriging models than with response surface models.
Comparing HTN Planning Method With Grammar-Based Approach in Generative Design
Authors: Shi Hai , Schmidt Linda C.
Published: December 2020

In mechanical conceptual design, the more design alternatives generated, the higher the benefit to designers. In this paper we explore the use of HTN planning, an artificial intelligence planning method, to perform generative conceptual design. The HTN planning method is “goal driven” while the grammar method is “feasibility driven”. We mapped a grammar-based generative method for conceptual design of Meccano carts into an HTN planning problem format. An initial comparison of the two methods is provided in this paper. Exploring the use of a planning method provides a benchmark for future research in generative design.
Skeleballs: Skeleton/Metaball Hybrid Solid Models for Automated Shape Generation
Authors: Storti Duane W. , Ganter Mark A. , Turkiyyah George M. , Brooking Cole
Published: December 2020

In this paper, we describe a solid modeling representation that incorporates metaballs and skeletons to create a hybrid representation called “skeleballs”. Skeleballs support the kind of robust editing and range of shape deformation needed for automated shape generation. Metaballs are an implicit representation based on blended spherical objects; they provide flexibility and smooth localized deformations. Skeletons are reduced-dimensional shape descriptors that capture essential geometric and topological characteristics and enable construction of a well-behaved implicit solid representation. Robust deformation is attained by superposing metaball functions on a skeleton-based implicit representation. Automated local parametrization of the design space is obtained by simply placing metaballs at points distributed across the surface and employing their amplitudes as search parameters. The hybrid skeletal/metaball representation ensures solid validity under general deformation operations, readily supports topological changes, provides for the generation of shape parametrizations, and supports multi-resolution editing. The effectiveness of the hybrid representation is demonstrated in the context of an automated shape generation example.
Design of Fused-Deposition ABS Components for Stiffness and Strength
Authors: Rodríguez José F. , Thomas James P. , Renaud John E.
Published: December 2020

The high degree of automation of Solid Freeform Fabrication (SFF) processing and its ability to create geometrically complex parts to precise dimensions provide it with a unique potential for low volume production of rapid tooling and functional components. A factor of significant importance in the above applications is the capability of producing components with adequate mechanical performance (e.g., stiffness and strength). This paper introduces a strategy for the optimizing the design of Fused-Deposition Acrylonitrile-Butadiene-Styrene (FD-ABS) components for stiffness and strength. In this strategy, a mathematical model of the structural system is linked to an approximate minimization algorithm to find the settings of select manufacturing parameters which optimize the mechanical performance of the component. The methodology is demonstrated by maximizing the load carrying capacity of a two-section cantilevered FD-ABS beam.
Implementation and Analysis of a Mechanics Simulation Module for Use in a Conceptual Design System
Authors: Jansson Johan , Horváth Imre , Vergeest Joris S. M.
Published: December 2020

Previously, we have described the theory of a general mechanics model for non-rigid solids (Jansson, Vergeest, 2000). In this paper, we will describe and analyze the implementation, i.e. algorithms and analysis of their time complexity. We will reason that a good (better than O(n2), where n is the number of elements in the system) time complexity is mandatory for a scalable real time simulation system. We will show that, in simplified form, all our algorithms are O(n lg n). We have not been able to formally analyze the algorithms in non-simplified form, we will however informally discuss the expected performance. The entire system will be empirically shown to perform slightly worse than O(n lg n), for a specific range and typical input. We will also present a working prototype implementation and show it can be used for real time evaluation of reasonably complex systems. Finally we will reason about how such a system can be used in the conceptual design community as a simulation of traditional design tools.
Intelligent Optimal Adaptive Mesh During Inelastic Analysis of Structures
Authors: Zarka Joseph , Hablot Jean Michel
Published: December 2020

During inelastic analysis, actually, only estimations of the errors are made what is not sufficient. Very often, even if these estimators are very small, this does not imply that the errors i.e. the difference between the exact solution of any field (stress, strain, energy ...) and the approximated solution of the field obtained with the numerical simulation, is small!

Sometimes, Engineers will perform the numerical simulations, then they will reduce the mesh according some rules, and if the new solution is not too far from the previous one, they will take it as a good one. This is very expensive and this is not efficient. Indeed, a lot of expertise is needed during the numerical simulations with also experimental correlations.

It is practically important to have a method where, when the range of the error (that will never be known in principle) is required, it is possible to indicate a priori the minimum cost (or Number of Degrees of Freedom or number of nodes) and to draw the optimal mesh (i.e. with this minimal number) to reach this error.

We shown, with automatic learning, that it is possible to extract some useful rules.

The main difficulty is that only a few examples of EXACT INELASTIC SOLUTIONS are known (cylinder, sphere with symmetrical loadings!) and in order to perform any automatic learning, it is necessary to have a data base of representative examples which contains several elastoplastic structures, their discretizations and for each of them the known errors!!
Autogenetic Design Theory: A Contribution to an Extended Design Theory
Authors: Vajna Sándor , Bercsey Tibor , Clement Steffen , Mack Peter
Published: December 2020

Based on an analysis of the product development process and the study of relevant product development models, the paper presents a new approach aiming at modeling and supporting the design activity as the substantial activity within the product development process. The Autogenetic Design Theory is an approach advancing general design theories. It facilitates the integration of intuition, creativity and artificial intelligence into the conventional design process. To this end, a phase-like allocation of the design process is assumed as the essential structure and an evolutionary algorithm is integrated as the core facilitating purposeful searching and combining. Hence, the flow of the design process can be influenced as all requirements can be included and, on the other hand, intuition and creativity are ensured through the evolutionary algorithm.
Development of an Interactive Web-Based Design Support System for the Lubrication of Rolling Bearings
Authors: Toussaint J. , Cheng K.
Published: December 2020

It is very important for designers, engineers, and even researchers to quickly and responsively get design data whenever and anywhere as needed. Internet is an enabling technology to make this be becoming a reality. In last few years, many improvements have been made in the information sharing through the WWW (World Wide Web). But in the CAD/CAM area it is still at an early stage. The aim of this paper is to explore various aspects of how to implement a Web-based engineering design support system which would allow the simulation of mechanical assemblies with parametric facilities, through the example of design of rolling bearings. The paper concludes with a discussion on the potential and applications of the approach and the system proposed.
A Generic Integration Approach to the Design and Manufacture of Scroll Compressors
Authors: Cheng K. , Jiang Z. , Harrison D. K.
Published: December 2020

This paper presents a generic integration approach to the design and manufacture of scroll type compressors which are becoming popular and widely used in refrigeration and air conditioners. To design and manufacture scroll compressors, however, is not easy for the reasons that their key parts have complex shapes with involute curves. The authors have developed a design approach that can cope with simultaneous design activities concurrently within one single environment. The approach is implemented by using Pro/ENGINEER and Visual C++ programming. The work presented is focused on the integration of Constructive Solid Geometry (CSG) solid modelling, FEM and CAM. With this particular approach a correct and precise solid model can be achieved, which leads to an optimal design in terms of specification adherence, quality, delivery time and cost. The paper concludes with a discussion on the potential and applications of the approach for mechanical product design.
Computerized Simulation of Enveloping Process for Different Applications
Authors: Goldfarb V. I. , Voznyuk R. V.
Published: December 2020

Application domain of the enveloping method is very wide and includes numerous engineering applications. The method has been widely applied for the formation of various surfaces, including gear flanks.

So called ‘nondiffferential’ method for enveloping process simulation has been developed; the method makes possible adequate description of the process. The method had laid the foundation for the development of a general-purpose software package which is used for the simulation of screw surface formation by different types of cutting tools, computation of tool profile needed to machine defined screw surface, determination of the profile of a gear tooth machined by a tool with defined geometry, computation of gear contact points coordinates, and other tasks. The computer program is modular in design, with a number of common units for the description of enveloped link geometry, enveloping process simulation, motion description, and units related to the solution of specific applied tasks.
Post Optimal System Analysis Using Aggregated Design Impact Matrix
Authors: Krus Petter
Published: December 2020

In this paper the concept of the Aggregated Design Impact Matrix, ADIM, is introduced. This is a tool to calculate and present the relative importance of whole components and subsystems (instead of individual parameters) on different system characteristics.

Optimisation is a well-established procedure for system development. Here a non-gradient method is used. Although the sensitivities are not calculated explicitly they can be estimated from the sequence of parameter sets evaluated during the optimisation. The technique used here is recursive least square.
Properties of the Coupled Factors in MDO and Their Application in Collaborative Optimization
Authors: Chen Baihong , Liu Jihong , Zhong Yifang , Zhou Ji
Published: December 2020

It is difficult to use multidisciplinary design optimization (MDO) method in the complex product optimization because of the existence of coupled factors. In order to help solve this problem, the components and affection of coupled factors are analyzed first in this paper. Then the coupled factors are divided into three classes. According to the global sensitivity equations (GSE), the properties of couplings between sub-systems are analyzed. The criterion that can confirm a redundant coupled factor has been derived and is applied to collaborative optimization by handling the couplings on the basis of coupled properties. An example is given to show the results achieved.
Collaborative Design Using Trade-Off Satisfying Method in Supervisor System
Authors: Miyashita Tomoyuki , Yamakawa Hiroshi
Published: December 2020

Recent years, financial difficulties led engineers to look for not only the efficiency of the function of a product but also the cost of its development. In order to reduce the time for the development, engineers in each discipline have to develop and improve their objectives collaboratively. Sometimes, they have to cooperate with those who have no knowledge at all for their own disciplines. Collaborative designs have been studied to solve these kinds of the problems, but most of them need some sorts of negotiation among disciplines and assumes that these negotiations will be done successfully. However, in the most cases of real designs, manager of each discipline does not want to give up his or her own objectives to stress on the other objectives. In order to carry out these negotiations smoothly, we need some sort of evaluation criteria which will show efficiency of the product considering the designs by each division and if possible, considering the products of the competitive company, too. In this study, we use Data Envelopment Analysis (DEA) to calculate the efficiency of the design and showed every decision maker the directions of the development of the design. We will call here these kinds of systems as supervisor systems and implemented these systems in computer networks that every decision maker can use conveniently.

Through simple numerical examples, we showed the effectiveness of the proposed method.
Stability Analysis of a Load Sensing Hydraulic Transmission System Modeling and Simulaton Approach
Authors: Saha Rana , Khutia Niloy , Maiti Rathindranath
Published: December 2020

An energy saving hydraulic system, known as load-sensing hydraulic system, to improve the efficiency of transmitting power from the pump to load has been studied in the present work. Due to the addition of the load sensing mechanism stability characteristics deteriorate in this system. A nonlinear mathematical model followed by a simulation model using SIMULINK has been developed to study the effect of system parameters on stability. Simulation results are verified with existing theoretical and experimental results.
Prediction of Wrinkling Behavior for Nonaxisymmetric Sheet Metal Parts by the Use of Finite Element Method
Authors: Senalp Zafer A. , Kaftanoglu Bilgin
Published: December 2020

Wrinkling is a defect occurring in the flange part of the blank during the metal forming operation. There is not much previous work related with the wrinkling of nonaxisymmetric parts. In this work finite element method is used to obtain the wrinkled behavior of nonaxisymmetric parts. Shell element with five degrees of freedom is formulated and used in the program. The developed nite element program can both be used with and without blank holder application. The permanent deformed shape after wrinkling is also obtained. The theoretical results are compared with the experimental values.
Theoretical Foundations for Tuning Parameter Tolerance Design
Authors: McAdams Daniel A. , Wood Kristin L.
Published: December 2020

In this paper a novel technique is presented to solve tolerance design problems. To achieve the desired performance tolerance, the technique uses a subtle, but significant, change in the design rather than increasing component precision. This change is the addition of a tuning parameter. Statistical models are used to developed a framework for the tuning parameter design method. Also developed is a new dimensionless design parameter which ranks candidate tuning parameters. The step-by-step tuning parameter design method is applied to a heavy duty manual stapler as a clarifying example.
Applying Case-Based Reasoning to Mechanical Bearing Design
Authors: Qin Xiaoli , Regli William C.
Published: December 2020

Case-Based Reasoning (CBR) provides a promising methodology for solving many complex engineering design problems. CBR is based on the idea that past problem-solving experiences can be reused and learned from in solving new problems. This paper presents an overview of a CBR design system to assist human engineers in performing mechanical bearing design. It retrieves previously designed cases from a case-base and uses adaptation techniques to adapt them to satisfy the current problem requirements. Our approach combines parametric adaptations and constraint satisfaction adaptations. The technique of parametric adaptation considers not only parameter substitution, but also the interrelationships between the problem definition and its solution. The technique of constraint satisfaction adaptation provides a method to globally check the design requirements to assess case adaptability. Currently, our system has been tested in the rolling bearing domain.
Profit Maximisation While Considering Uncertainty by Balancing Commonality and Variety Using Robust Design: The Redesign of a Family of Lift Tables
Authors: Blackenfelt Michael
Published: December 2020

Traditionally modular products refer to products that fulfil various overall functions through the combination of distinct building blocks. The most central idea behind product modularisation is to retain or even increase customer satisfaction through product customisation, while increasing or retaining economy of scale. However, both business and technical aspects must be considered in order to find the right balance between commonality and variety and thus between low cost and distinctive product performance. This paper outlines a balancing approach based on available cost models and a transfer of product performance to monetary terms using the so-called quality loss function. Based on the economical relations, Robust Design is employed to optimise the degree of variety in order to maximise the profit while considering the forecast uncertainty.
Error Analysis for the In-Situ Fabrication of Mechanisms
Authors: Goel Puneet , Rajagopalan Sanjay , Cutkosky Mark R.
Published: December 2020

Fabrication techniques like Solid Freeform Fabrication (SFF), or Layered Manufacturing, enable the manufacture of completely pre-assembled mechanisms (i.e. those that require no explicit component assembly after fabrication). We refer this manner of building assemblies as in-situ fabrication. An interesting issue that arises in this domain is the estimation of errors in the performance of such mechanisms as a consequence of manufacturing variability. Assumptions of parametric independence and stack-up made in conventional error analysis for mechanisms do not hold for this method of fabrication.

In this paper we formulate a general technique for investigating the kinematic performance of mechanisms fabricated in-situ. The technique presented admits deterministic and stochastic error estimation of planar and spatial linkages with ideal joints. However, only a planar example is illustrated in this paper. Errors due to joint clearances, or other effects like flexibility and driver-error, are not considered in the analysis — but are part of ongoing research.
Assembly Quality Method: A Tool in Aid of Product Strategy, Design, and Process Improvements
Authors: Beiter Kurt A. , Cheldelin Brent , Ishii Kosuke
Published: December 2020

This paper describes a new methodology for assisting manufacturing companies in predicting the defect levels of new products at globally distributed production facilities. This paper builds on the traditional design for assembly as well as the Total Quality Assurance methods. The proposed method, Assembly Quality Methodology (AQM), uses the conventional assembly evaluation method along with a set of equations to predict defect rates for different assemblies at various manufacturing sites. AQM relates defect rates with the complexity metrics calculated using existing assembly evaluation methods. The paper discusses potential strategic uses of this information such as overall product assembly strategy across globally distributed manufacturing and supply chain, product modularity decisions, and improvements in products and processes for assembly.
Configuration Analysis to Support Product Redesign for End-of-Life Disassembly
Authors: Viswanathan Shivakumar , Allada Venkat
Published: December 2020

End of life disassembly is an important process that can be used to make available the parts of a product for different material and part recycling processes at end of the product’s useful life. However, the efficiency of the disassembly process greatly affects the economics of meeting the environmental goals set for the product. An important determinant of the disassembly efficiency is the product configuration. Therefore, it is essential that these implications of the configuration be assessed and modified during the design stage itself. To support this design effort a formal model called the Configuration-Value (CV) model is proposed to evaluate and analyze the effect of product configuration on end-of-life disassembly. This model focuses on the rate of value extraction during the disassembly process and can be used to identify the critical bottlenecks in the configuration that need rectification by design. An example is presented to demonstrate the application of the proposed model.
Modeling Compliant Part Assembly: Mechanics of Deformation and Contact
Authors: Mattikalli Raju , Mahanian Saba , Jones Alan , Clark Greg
Published: December 2020

This paper describes an approach to model the mechanics of assembly by assuming parts are compliant. The approach involves a model of contact between compliant bodies based on variational inequalities. This approach has a number of advantages over current finite element codes, which rely on traditional variational approaches such as penalty force methods and Lagrange multipliers to resolve multiple unknown contact conditions. From a mathematical point of view, contact problems among compliant parts are particularly difficult to handle due to the fact that contact constraints are not permanently active, but depend on deformations. They are inherently non-linear and irreversible in character. To obtain a more mathematically robust way of modeling contact, we present a variational inequalities based approach that produces a quadratic programming (QP) problem. The QP is solved to resolve contact situations and obtain the mechanics of parts during assembly. We apply the method to simulate and design aircraft assembly processes.
On the Exact Computation of the Swept Surface of a Cylindrical Surface Undergoing Two-Parameter Rational Bézier Motions
Authors: Xia J. , Ge Q. J.
Published: December 2020

This paper extends the recent work of Xia and Ge (1999) to develop methods for the exact analysis of the swept surface of a cylindrical surface undergoing two-parameter rational Bézier motions. Instead of the approach of analyzing the point trajectory of an object motion for swept volume analysis, this paper seeks to develop a new approach to swept volume analysis by studying the plane trajectory of a rational motion. It seeks to bring together recent work in swept volume analysis, plane representation of developable surfaces, as well as computer aided synthesis of freeform rational motions. The results have applications in design and approximation of freeform surfaces as well as tool path planning for 5-axis machining of freeform surfaces.
Comparative Analysis and Experimental Verification of the Computed Shape of a Flexible Blade Tool for FF-TLOM
Authors: de Smit Bram , Medland Anthony J. , Broek Johan J. , Horváth Imre , Lennings Alex F.
Published: December 2020

A novel technology introduced by the authors as free form thick layered object manufacturing (FF-TLOM), aims specifically at the field of large sized free form objects. The system under development will be able to produce large editable free form prototypes that can be used in the conceptual phase of the design. The considered technology of cutting polystyrene slabs using a heated flexible cutting blade is developed and currently being optimized. Work has been done already on the control of the actual cutting process by elaborating experiments on a range of influential process parameters. A further step is the accurate control of the shape of the flexible cutting device. Theories are known for the calculation of the shape of a flexible bar under specific constraints. The known theories and algorithms must be validated by experimental verification. The paper describes explorative experiments with the aim to develop a method that can be used for this experimental verification. Two implemented algorithms for the calculation of blade shapes are described as well as a number of calculations that were performed using these algorithms. The calculated results are being compared to each other and to real world experiments in order to determine their validity. The results of the experiments indicate that both of the algorithms could be applied for our shape calculations, however more experiments and analysis have to be performed on the subject. It becomes clear that small deviations in the applied constraints can, under specific circumstances, have large effects on the generated blade shapes.
On Evaluation Method During Conceptual Design
Authors: Huang Yuan Mao , Liao Chung-Cheng
Published: December 2020

This study proposes an evaluation method that integrates the existing ordinal, cardinal and matrix methods for decision making. Normalized values are recommended for the pairwise comparisons of evaluation items to determine the weighting factors. These values also assist in determining the weighting eigenvectors for alternatives of the potential products. Web diagrams are generated for all alternatives and their areas are compared to identify the most preferred one. The proposed method can reduce drawbacks of the Pahl and Beitz method and the Saaty method when the two most preferred alternatives have the same summed weighted values in the Pahl and Beitz method or the same composite weighting factors in the Saaty method.
A Product Design System Employing Optimization-Based Tradeoff Analysis
Authors: Ball Michael O. , Fleischer Mark A. , Church Douglas G.
Published: December 2020

Decision-based design (DBD) attempts to integrate an array of disparate elements into a system-level analytical tool. This paper presents some practical and easily implemented approaches for a design optimization system that takes into account the multi-objective problem domains typically encountered in most manufacturing settings. This approach utilizes tradeoff analysis, graphical displays and embedded optimization techniques to provide a designer with design alternatives during the conceptual level design phase of product development.
Function Integration Explained by Allocation and Activation of Wirk Elements
Authors: Jensen Thomas
Published: December 2020

In mechanical engineering design, the conceptual design phase involves the determination of the structural means for realizing the functions of a product. Function integration is a means for achieving an efficient design, where the same means contributes to the realization of multiple functions. This paper contributes to a phenomenological understanding of function integration and aims at refining design theories treating this subject. The work rests upon and contributes to German design theory and the design theories of the WDK School.

For explaining function integration, the concept of wirk element is introduced. A wirk element is defined as a functionally active form element that is part of an organ and contributes to the realization of a function. Furthermore, based upon the allocation and activation of wirk elements, a definition of function integration is given, and six kinds of integration are classified. Finally, opportunistic design is explained by the wirk element concept and the implication of function integration on product modeling in configuration systems is treated.

Throughout the paper, several examples are given to illustrate the explanatory power of the proposed modeling concept.
Enabling the Use of Shape Grammars: Shape Grammar Interpretation Through General Shape Recognition
Authors: McCormack Jay , Cagan Jonathan
Published: December 2020

Shape grammars have recently shown promise in engineering applications. The need to efficiently implement such grammars, rather than hard code them, in a way that supports creativity through shape emergence has still remained an ongoing research challenge. This paper introduces a shape grammar interpreter that supports parametric shape recognition, and thereby shape emergence. The approach divides shapes into hierarchies of subshapes based on specified geometric relationships within the shape. A default hierarchy based on geometric relations often found in engineering and architectural designs is presented as an efficient example of one appropriate hierarchy. A classic shape grammar demonstrates the interpreter’s shape recognition and generation abilities.
Application of Design Axioms to Marine Design Problems
Authors: Yang Y. S. , Jang B. S. , Song Y. S. , Yeon Y. S. , Do S. H.
Published: December 2020

The Design Axioms proposed by N. P. Suh consist of Independence Axiom and Information Axiom. The Independence Axiom assists a designer in generating good design alternatives by considering the relations between the functions and the physical product using a hierarchical mapping procedure. The Information Axiom, which is related to the probability of achieving the given functional requirements, can be used as a criterion for the selection of the best solution among the proposed alternatives in the conceptual or preliminary design stage.

In the early stages of marine design, especially ship design, there exists a lot of uncertainty because of the size and complexity of a marine vehicle. The uncertainty often leads to a probabilistic approach rather than a deterministic approach. The ship designs are mostly routine design to change an existing design case a little. In this paper, the availability of the Design Axioms in this marine design field will be investigated through three examples.

In the conceptual design of a thruster, the Independence Axiom will be proven to be useful in examining the independence of functional requirements at each level of the decomposition process. In main engine selection example, the Information Axiom will be used for selecting the best solution among the given alternatives by estimating their respective information contents under the uncertain and ambiguous condition.

In the structural design, some difficulties arise in maintaining the independence of functional requirements in general because the number of design parameters is greater than that of functional requirements. Therefore, there is much trouble in generalizing the application of the Design Axioms for the structural design, especially for the preliminary design where the principal design parameters of a design object have to be determined after its shape fixed. This paper will try a generalized approach to the similarity-based design where it is important to select which parameters should be changed and in what order they should be changed. How to make use of the Design Axioms will be showed in a barge design example. However, a lot of research is needed for the generalized application of the Design Axioms for the structural design.
Enhancing Product Development Efficiency Through Changes With a Holistic Strategy
Authors: Beskow Cecilia
Published: December 2020

The paper forms an overview of current product development procedures within companies in Northern California, in particular with respect to the issues affecting collaboration. Guidelines for obtaining more efficient product development are presented, firmly established in the empirical material. The results and conclusions are based on thirty-six qualitative research interviews in six companies. Problems regarding collaboration issues are described, as well as activities performed to improve efficiency in general and team collaboration in particular. Furthermore, the conclusions suggest a framework to be considered when establishing a support structure for solutions aimed at improving collaborative work within an organization.
Computer Based Requirement and Concept Modelling: Information Gathering and Classification
Authors: Andersson Fredrik , Nilsson Patrik , Johannesson Hans
Published: December 2020

This paper proposes a requirement and concept model based on a functional decomposition of mechanical systems. It is an object-oriented approach to integrate the representation of the design artefact and the design activity, through the decisions made during the design evolution. The requirements co-evolve simultaneously with the formation of the conceptual layout, through the opportunity to alter between function and physical/abstract solutions. This approach structures the design requirements and concepts in such a way that it supports the ability to document their sources, to allow for validation and verifications of both requirements and design solutions.

First, the proposed model is presented from a theoretical viewpoint. Secondly, a methodology for modelling requirements and concepts in an object-oriented fashion is discussed. Finally, the model is implemented in METIS software and tested in a case study of an electric window winder on a truck door.
Metamodeling of Combined Discrete/Continuous Responses
Authors: Meckesheimer Martin , Barton Russell R. , Limayem Frej , Yannou Bernard
Published: December 2020

Metamodels are effective for providing fast-running surrogate measures of product or system performance. Instantaneous performance estimation can allow designers to pursue design alternatives interactively, a methodology different from traditional case-based or optimization-based design. Metamodel approximations are generally based on continuous functions, and therefore they can be poor at fitting discontinuous responses. Many engineering models produce functions that are only piecewise continuous, due to changes in modes of behavior or other state variables. This paper shows that a state-selecting metamodel approach can provide an accurate approximation for piecewise continuous response functions. The method is applied to a desk lamp performance model.
Diagnostic Analysis for Mechanical Systems
Authors: Henning Scott , Paasch Robert
Published: December 2020

An analysis and modeling method of the diagnostic characteristics of a mechanical or electromechanical system is presented. Diagnosability analysis is especially relevant given the complexities and functional interdependencies of modern-day systems, since improvements in diagnosability can lead to a reduction of a system’s life-cycle costs. Failure and diagnostic analysis leads to system diagnosability modeling with the Failure Modes and Effects Analysis (FMEA) and component-indication relationship analysis. Methods are then developed for translating the diagnosability model into mathematical methods for computing metrics such as distinguishability and susceptibility. These methods involve the use of matrices to represent the failure and replacement characteristics of the system. Diagnosability metrics are extracted by matrix multiplication. These metrics are useful when comparing the diagnosability of proposed designs or predicting the life-cycle costs of fault isolation.
Defect-Free Slider-Crank Function Generation for 4.5 Precision Points
Authors: Stumph Herbert E. , Murray Andrew P.
Published: December 2020

The well-established methodology for slider-crank function generation states that 5 precision points can be achieved with no structural error. The resulting designs, however, do not necessarily satisfy all of the kinematic requirements for designing the slider-crank linkages used to drive the ram of a mechanical press. First, solutions to the 5 precision point synthesis problem may not have the precision points on one circuit. Additionally, there is no guarantee of a fully rotatable input crank. In this paper we present 4.5 precision point synthesis, a modification to the 5 precision point methodology for designing slider-cranks with fully rotatable input links and all precision points on the same circuit. The 4.5 precision point function generation methodology is illustrated with an example.
Active Vibration Control for the Closed Loop Flexible Mechanisms Combined the Feedback and Feed-Forward Strategy: Part 2 — Control Design and Simulation
Authors: Xianmin Zhang , Changjian Chao
Published: December 2020

On the basis of the complex mode theory and the equations of motion of the flexible mechanisms developed in part 1, a hybrid independent modal controller is presented, which is composed of state feedback and disturbance feed-forward control laws. As an illustrative example, the strategy is used to control the elastic vibration response of a four-bar linkage mechanism. The imitative computational result shows that the vibration is efficiently suppressed.
Real-Time Forward Kinematics of the General 6-6 Stewart Platform Using One Extra Sensor
Authors: Lee Tae-Young , Shim Jae-Kyung
Published: December 2020

The forward kinematics of the Stewart platform is to find the postures of the moving platform for a given set of leg lengths. In case of the general Stewart platform, the number of solutions of the problem is up to forty in the complex domain. Theoretically, it is not possible to uniquely determine the actual configuration with six leg length measurements only. An approach to get a single actual configuration is to make over-constrained system by adding extra sensors. This paper presents an algebraic elimination-based method for the real-time forward kinematics of the general Stewart platform with one extra sensor. The proposed algorithm does not require initial estimates of solutions unlike the numerical iterative methods, and can be implemented in C language using conventional double precision data with 15 significant digits. A numerical example is given to confirm the effectiveness and correctness of the developed algorithm for real-time computation.
Polynomial Solution to the Five-Position Synthesis of Spatial CC Dyads via Dialytic Elimination
Authors: Huang Chintien , Chang Yu-Jui
Published: December 2020

This paper presents a polynomial solution to the five-position synthesis of spatial cylindrical-cylindrical dyads. The solution procedures start with the simplification of the synthesis equations derived by Tsai and Roth. The simplified equations are solved by Sylvester’s dialytic elimination method to obtain a univariate polynomial equation of degree six, which gives at most 6 CC dyads for the five-position synthesis. A numerical example with six real solutions is provided.
Microfabrication and Characterization of Electro-Thermal-Compliant Micro Devices
Authors: Li Jun , Ananthasuresh G. K.
Published: December 2020

Electro-Thermal-Compliant (ETC) micro devices are a new class of compliant mechanisms that elastically deform in response to Joule-heating induced constrained thermal expansion. In ETC devices, the mechanism and the actuator are indistinguishable and therefore it is called embedded actuation. This type of actuation is attractive for Micro-Electro-Mechanical Systems (MEMS) where the actuator is often much larger than the mechanism and the mechanical coupling of the actuator and mechanism leads to additional difficulties. In this paper, we focus on thin, planar, appropriately shaped, deformable structures made of a conducting material to fabricate micro mechanisms with embedded actuation. We have developed a bulk micromachining process, called PennSOIL, using silicon-on-insulator (SOI) wafers to make silicon ETC devices, and also combined PennSOIL with excimer laser micromachining to make ETC devices with not only silicon but also a variety of metals. The experimental measurements are compared with the theoretical predictions. Test-structures are used to characterize the process and the resulting materials properties some of which are strongly temperature-dependent and process-dependent. The experimental results using the materials properties obtained from the test structures show agreement with the theoretical results.
On the Placement of Serial Manipulators
Authors: Abdel-Malek Karim , Yu Wei
Published: December 2020

Criteria and implementation for the placement robot manipulators with the objective to reach specified target points are herein addressed. Placement of a serial manipulator in a working environment is characterized by defining the position and orientation of the manipulator’s base with respect to a fixed reference frame. The problem has become of importance in both the medical and manufacturing fields, where a robot arm must be appropriately placed with respect to targets that cannot be moved. A broadly applicable numerical formulation is presented. While other methods have used inverse kinematics solutions in their formulation for defining a locality for the manipulator base, this type of solution is difficult to implement because of the inherent complexities in determining al inverse kinematic solutions. The approach taken in this work is based on characterizing the placement forcing a cost function to impel the workspace envelope in terms of surface patches towards the target points and subject to functionality constraints, but that does not require the computation of inverse kinematics. The formulation and experimental code are demonstrated using a number of examples.
Design and Analysis of a Four-Degree-of-Freedom Hybrid Spherical Scanning Apparatus
Authors: Chen Chuanqi , Li Perry Y. , Erdman Arthur G.
Published: December 2020

The design of a novel scanning apparatus used for digitizing dental impression molds is presented. The apparatus consists of a four-degree-of-freedom hybrid spherical linkage capable of moving the dental mold relative to a laser scanner along a curved path in the specified orientations. Since closed form inverse kinematics solutions are not available for the multiple degree-of-freedom spatial mechanism in question, symbolic and numerical computation techniques are used extensively for kinematics analysis, dimension design, and optimization. In addition, mechanical design and simulation software (Pro/Engineer & Pro/Mechanica), as well as the rapid prototyping machines are used to reduce the development cost and cycle time.
Design of the Stackbot™ Cam Track Palletizer/Material Handling Device
Authors: Derby Stephen , Kirchner Ned
Published: December 2020

A novel palletizing/material handling device has been created. This novel design (US patent applied for) was developed by assessing the needs of many industrial companies. This device trades the unlimited flexibility and position addressability of standard servo driven robots and material handling machines for a limited set of palletizing locations, by use of a multi track cam plate. The resulting combinations of reduced complexity degrees of freedom result in a less expensive and more marketable product.
PennSyn: A Topology Synthesis Software for Compliant Mechanisms
Authors: Saxena A. , Wang X. , Ananthasuresh G. K.
Published: December 2020

In this paper, we present PennSyn, a software with graphical user interface that provides an automated design route from function specifications to fabrication of fully compliant mechanisms. PennSyn uses the notion of maximizing the flexibility and stiffness of a continuum simultaneously through multi-criteria objectives for the topology synthesis of compliant mechanisms. Both the optimality criteria and quasi Newton mathematical programming methods are employed as optimization algorithms in PennSyn. Reliability in the optimality criteria method is ensured using a one variable search while the volume constraint is addressed by global resizing of variables without altering the function value locally. The design continuum is represented using ground structures of linear truss and frame finite elements. These element types are easy and robust in implementation and help provide effortless extraction and transfer of optimal topologies into commercial CAD packages. An edge detection algorithm is used with PennSyn for boundary extraction of optimal compliant geometries. The resulting data is stored in IGES format for easy portability into commercial modeling and analysis software packages.
Multiple-Segment-Pseudo-Rigid-Body Model Concept in Compliant Mechanism Design and Analysis
Authors: Mettlach Gregory A. , Midha Ashok
Published: December 2020

The concept of a pseudo-rigid-body model for a flexible member proven very instrumental in the design and analysis of compliant mechanisms. It provides a means by which a compliant mechanism may be modeled as an equivalent pseudo-rigid-body mechanism. This makes it possible for compliant mechanisms to be analyzed and designed using a wealth of existing methods for rigid-body mechanisms. Oftentimes, however, it is not possible to model a compliant member with a typical pseudo-rigid-body model. This may be due to a force or displacement boundary condition applied to a compliant member at a point other than the beam end. For situations such as these, a planar, multiple-segment pseudo-rigid-body model concept is introduced which allows arbitrary beam type compliant members, regardless of geometry, loading, or boundary conditions, to be modeled as an assemblage of rigid members with torsional springs at characteristic pivots. This methodology enables existing analysis and synthesis methods to be applied in the design of complex compliant mechanisms.
Gait Planning for Quadruped Turning
Authors: Ye Tina Y. , Song Shin-Min
Published: December 2020

Gait planning for turning is important to the control of legged locomotion. For practical reason, it is necessary for a quadruped to change its walking direction without slowing down or making a stop. In this paper, we formulate a gait planning which enables a quadruped walking in a straight line to change its gait to increase stability first, make a turn and finally recover to its original gait for straight-line walking. All of this is performed under a constant speed condition. The result shows that with some simple foot adjustments, the turning can be initiated at any foot lifting or placing event during a cycle.