bluuebunny/crossref_metadata_2025 huggingface dataset:
Classification of Designs for RRSS Linkages
Authors: Su Haijun , McCarthy J. Michael
Published: November 2020

This paper presents a classification of designs for an RRSS spatial linkage. The analysis of this linkage results in a well-known constraint equation that defines the configuration of the chain for given values of the input crank angle. The range of movement of this crank is defined by a condition on the values of the input crank angle. This condition is a quartic polynomial and its real roots provide a way to classify the movement of the RRSS linkage. This condition yields as many as four real roots, which means the input crank angle of an RRSS linkage can have up to four limits to its range of movement. We use three polynomial discriminants obtained from this quartic condition in order to find explicit conditions for all cases available for the movement of the input crank. Examples for each case are provided. This result provides a means to classify the RRSS linkage, and is important for the computer-aided-design of these spatial mechanisms.
Utility-Based Decision Support for Selection in Engineering Design
Authors: Fernández Marco Gero , Seepersad Carolyn Conner , Rosen David W. , Allen Janet K. , Mistree Farrokh
Published: November 2020

In this paper we present a utility-based method for selection in engineering design. The Utility-Based Selection DSP supports a designer in making selection decisions involving both tradeoffs among multiple, conflicting attributes and risk or uncertainty associated with these attributes. The method is quantitative as well as axiomatic, designed to facilitate rational decision-making that is consistent with assessed designer preferences. We illustrate use of the Utility-Based Selection DSP through application in a rapid prototyping context. The goal here is to select appropriate rapid prototyping technology and material combinations for testing the snap-fit design of a light switch cover plate. Overall, our focus is to present both method and example in sufficient detail for application by others.
Capturing Assembly Tolerances and Criteria in a Common Model
Authors: Morse Edward P.
Published: November 2020

Assemblies of mechanical parts are typically modeled as collections of rigid solids, constrained by contact conditions at “mating” faces. We have previously proposed a method — called GapSpace — of modeling and representing assemblies with constraints arising from either face adjacency or face contact. This method of specification allows less restrictive tolerances to be placed on the assembly components, resulting in specifications that are less expensive to meet. In this paper we show how various assembly metrics and criteria can be represented with GapSpace, and how to analyze toleranced assemblies for conformance to these criteria. These analyses show quantitatively the importance of deciding which part dimensions will have tolerances applied to them, in addition to the choice of the actual tolerance values.
Geometric Insight Into the Dynamics of a Rigid Body Using the Spatial Triangle of Screws
Authors: Pennock Gordon R. , Meehan Patrick J.
Published: November 2020

Geometric relationships between the velocity screw and momentum screw are presented, and the dual angle between these two screws is shown to provide important insight into the kinetics of a rigid body. Then the centripetal screw is defined, and the significance of this screw in a study of the dynamics of a rigid body is explained. The dual-Euler equation, which is the dual form of the Newton-Euler equations of motion, is shown to be a spatial triangle. The vertices of the triangle are the centripetal screw, the time rate of change of momentum screw, and the force screw. The sides of the triangle are three dual angles between the three vertices. The spatial triangle provides valuable geometrical insight into the dynamics of a rigid body and is believed to be a meaningful alternative to existing analytical techniques. The authors believe that the work presented in this paper will prove useful in a dynamic analysis of closed-loop spatial mechanisms and multi-rigid body open-chain systems.
Multidisciplinary Robust Design Optimization of an Internal Combustion Engine
Authors: McAllister Charles D. , Simpson Timothy W.
Published: November 2020

In this paper, we introduce a multidisciplinary robust design optimization formulation to evaluate uncertainty encountered in the design process. The formulation is a combination of the bi-level Collaborative Optimization framework and the multiobjective approach of the compromise Decision Support Problem. To demonstrate the proposed approach, the design of a combustion chamber of an internal combustion engine containing two subsystem analyses is presented. The results indicate that the proposed Collaborative Optimization framework for multidisciplinary robust design optimization effectively attains solutions that are robust to variations in design variables and environmental conditions.
Mouth Operated Neurosurgical Robot
Authors: Sugar Thomas G. , Fussell Paul
Published: November 2020

Medical robots in neurosurgery are currently used to accurately position a microscope in consonance with MRI images to allow positional awareness relative to important features of surgical focus. Currently, these robots must be “hand” adjusted by the surgeon, unlike the mouth-operated, counterbalanced linkages that are adjusted using a mouth interface. A human interface to the robot will allow smooth operation as well as new programmable motions not obtainable with the non-actuated microscope stands. A robotically guided microscope will be able to move in a spherical motion allowing for quicker and easier focus about a point of interest. Future work in robotic augmentation must certainly allow tools to be manipulated. As a first step, we mount a biopsy holder on a parallel robot and discuss the compliance issues of the entire system.
Defining Quality Appearance Index Weights by Combining VR and CAT Technologies
Authors: Wickman Casper , Söderberg Rikard
Published: November 2020

As markets become increasingly competitive and customers more demanding, virtual verification has become an important tool for cutting costs and shortening lead-times. So far, the main focus area for Virtual Reality (VR) tools has been to extend and support concurrent engineering between manufacturing and design in early stages of the development process. Today, when a styling concept of a product is evaluated in an aesthetic manner, all models used are nominal. If the styling concept is evaluated with nominal models, variation aspects and design solutions that would greatly influence the overall quality appearance will not be discovered until the first test series are made. By using non-nominal models during the design process, important geometric aspects can be issued, and the need for physical test series can be reduced.

In the automotive industry, especially within body design, the relations between doors, hoods, fenders and other panels are critical. Today, the quality appearance (QA) of vehicles is judged by these relations.

This paper describes how virtual reality technique is used to define a weight system for different prominent areas of a product when evaluating the quality appearance with QA index. It will also discuss how combining traditional Computer Aided Tolerance (CAT) tools with modern virtual reality tools has the potential to enhance concurrency between styling and design and provide more powerful support for the geometry process in early phases. Traditional non-nominal verification can then already be conducted in the concept phase using digital models instead of physical ones.

In the paper, today’s geometry design process at an automotive company is described. An example of the rear end of a vehicle is used to illustrate how integrated CAT/VR tools can be used to support decision making when allocating weights fore the quality appearance index.
Planar Cable-Direct-Driven Robots: Part I — Kinematics and Statics
Authors: Williams Robert L. , Gallina Paolo
Published: November 2020

A hybrid parallel/serial manipulator architecture is introduced where the translational freedoms are provided by a cable-direct-driven robot (CDDR) and the rotational freedoms are provided by a serial wrist mechanism. The motivation behind this work is to improve the serious cable interference problem with existing CDDRs and to avoid configurations where negative cable tensions are required to exert general forces on the environment. Only the translational CDDR is considered in this paper; including kinematics and statics modeling, and determination of the statics workspace (the space wherein all possible Cartesian forces may be exerted with only positive cable tensions). Examples are presented to compare the planar 3-cable CDDR with one degree of actuation redundancy and the 4-cable CDDR with two degrees of actuation redundancy. It was found that the 4-cable case requires less cable tensions and thus less energy compared to the 3-cable case in performing the same simulated tasks.
Quad-Layer: Layered Quadrilateral Meshing of Narrow Two-Dimensional Domain by Bubble Packing and Chordal Axis Transformation
Authors: Yamakawa Soji , Shimada Kenji
Published: November 2020

This paper presents a new computational method for quadrilateral meshing of a thin, or narrow, two-dimensional domain. An output mesh of our method is well-shaped and either single-layered, multi-layered, or partially multi-layered. Element sizes can be uniform or graded. A high quality, layered quadrilateral mesh is often required for finite element analyses of a narrow two-dimensional domain with a large deformation such as the analysis of rubber deformation or sheet metal forming. Our method consists of two steps: (1) extraction of the skeleton of a given domain by the discrete chordal axis transformation, and (2) discretization of the chordal axis into a set of line segments and conversion of each of the line segments to a single quadrilateral element or multiple layers of quadrilateral elements. In both steps we use a physically-based computational method called bubble packing to discretize a curve into a set of line segments of specified sizes. Experiments show that the accuracy of a large-deformation FEM analysis can be significantly improved by using a well-shaped quadrilateral mesh created by the proposed method.
Position Analysis for a Class of Novel 3-DOF Translational Parallel Robot Mechanisms
Authors: Jin Qiong , Yang Ting-Li
Published: November 2020

A class of new 3-DOF parallel robot mechanisms is investigated. Closed-formed solutions are developed for both the forward and inverse kinematics. Compared with known 3-DOF parallel robot mechanisms, these mechanisms are not only simple in structure with fewer solutions for position analyses but also decoupled. The mechanism decouplity, which is related to the topological characteristics, dimensional parameters, kinematic joint types and the choice of input-joints, is very useful for real control and path planning of parallel robots.
Force Based Model for Automated Surface Roughness Prediction in Slot Milling
Authors: Sarhan A. , Nasr A. A. , El-Zahry R. M.
Published: November 2020

Study was carried out to analyze the dynamic cutting signals of slot-milling process, in order to design automated on-line tool and surface roughness monitoring strategies, based on indices extracted from these signals, to automatically monitor and control surface roughness in slot milling.

Especially designed and manufactured sensitive strain gage dynamometer was used to measure slot-milling radial and tangential forces during milling cycle. The dynamometer was calibrated in static and dynamic ranges.

The effect of flank wear width on the magnitude of the cutting force harmonics was constructed as function of axial depth of cut, feed rate per tooth, specific cutting pressure of work material and instantaneous angle of rotation. The results were plotted at various cutting conditions in time and frequency domains.

The tool wear was measured in an off-line manner using the tool maker’s microscope and interrelationships of cutting force harmonics and tool wear magnitude were constructed and were used in the computer simulation. Surface roughness was measured using surface meter (Surtronic 3+) with a portable printer.

The cutting force signal harmonics were used to establish the proposed force based model to predict the surface roughness of the workpiece machined in slot-milling and examining this system by another experimental tests to define the reliability of the system and to define the percentage error of the system model. Hence, an index named as surface index (S.I) is extracted from ratio between first force amplitude at first significant frequency and first surface amplitude at the same frequency, to predict the surface roughness of the workpiece machined in slot-milling. This is to be employed in automated on-line quality management (monitoring and control) strategy.
Analytical Method for Mapping Function to Failure During High-Risk Component Development
Authors: Tumer Irem Y. , Stone Robert B.
Published: November 2020

Communicating failure mode information during design and manufacturing is a crucial task for failure prevention. Most processes use Failure Modes and Effects types of analyses, as well as prior knowledge and experience, to determine the potential modes of failures a product might encounter during its lifetime. When new products are being considered and designed, this knowledge and information is expanded upon to help designers extrapolate based on their similarity with existing products and the potential design tradeoffs. This paper makes use of similarities and tradeoffs that exist between different failure modes based on the functionality of each component/product. In this light, a function-failure method is developed to help the design of new products with solutions for functions that eliminate or reduce the potential of a failure mode. The method is applied to a simplified rotating machinery example in this paper, and is proposed as a means to account for helicopter failure modes during design and production, addressing stringent safety and performance requirements for NASA applications.
Automatic Setup Planning and Operation Sequencing for Satisfying Tolerance Requirements
Authors: Wu Yuguang , Gao Shuming , Chen Zichen
Published: November 2020

In this paper, a novel approach to automatic setup planning and operation sequencing of a part is proposed. The critical tolerance feature sets of the part are first identified by comparing the tolerance specifications with the capabilities of machine tools. Then, based on the concepts of critical tolerance feature set, the feature model of the part is decomposed into a series of identical setup feature (ISF) sets, each of which corresponds to a setup candidate. Finally, according to geometric precedence and tolerance precedence among features, the reasonable machining operations of features with multiple machining operations are determined, the ISF sets are sequenced and merged. Compared to previous work, the approach can generate the setup plan by which the part can be machined to satisfy the required tolerances. The approach also has high efficiency.
An Impact Analysis Methodology for Design of Products and Processes for Reliability and Quality
Authors: He David , Adamyan Angela
Published: November 2020

This paper presents an impact analysis methodology for design of products and processes for reliability and quality. Some important aspects in design of products and processes are to be able to estimate the impact of possible failures on product/process reliability and quality and be able to identify design alternatives that enhance product and process reliability and quality. The methodology presented in this paper combines the structural and qualitative analysis of Failure Modes and Effect Analysis (FMEA) techniques with dynamic and qualitative analysis of Petri net modeling approach and is able to analyze multiple failure effect and their impacts on reliability and quality of product and process design.
Form Follows Function: Case-Based Learning Over Product Evolution
Authors: Verma Manish , Wood William H.
Published: November 2020

The product design process operates over user needs to develop functional specifications which are further developed into physical forms. Manufacturing information fed into function-based design provides an effective tool for this function to form transformation. Multidisciplinary teams formed across the supply chain are charged with this process for large-scale product development. For small enterprises, however, integrating manufacturing information into the design process is more difficult. We propose a design by analogy approach based on design cases and associated manufacturing and life cycle information as an aid to product design. Reverse engineering of existing products over product generations is proposed as a source for the design cases. Potential metrics to differentiate good and bad cases are discussed. Ten different varieties of computer mice are used as a test case in this study.
The Machine Designs Behind Reference Free Part Encapsulation Fixturing
Authors: Lee Elmer , Sarma Sanjay
Published: November 2020

Reference Free Part Encapsulation (RFPE) is an automatic, universal workholding process developed by the researchers at MIT and Berkeley. In RFPE, a block of filler material encapsulates the workpiece and provides a fixturing surface, and after each machining operation, the filler block is re-filled with material to restore it to a perfect block. This paper shall describe the machines developed to test and demonstrate the theories and practices described by Reference Free Part Encapsulation. This paper will show the similarities of the encapsulation process to such manufacturing processes as die casting and injection molding. However, it shall also show that many intrinsic differences exist between the encapsulation process and an injection molding or die casting process. Two encapsulation machines will be presented. The first is a larger encapsulation machine capable of forming encapsulations with a 6″ by 6″ footprint. The second, a much smaller portable machine, capable of forming encapsulations with a 2″ by 2″ footprint, will also be presented. Special features of each encapsulation machine shall be highlighted and various design decisions shall be discussed.
Offset Blending Applied to Virtual Package Design
Authors: Narayanaswami Ranga , Ahuja Lalit
Published: November 2020

This paper discusses work towards developing a packaging solution on a virtual platform. Specifically, it addresses the techniques investigated to create a mold (package) for a single product item that needs to be packaged. Packaging in the context of this paper refers to designing packages for solids. It addresses the issues of offset and vertex blending that arises during the process of creating a mold-like package design for a product. The goal of package design in this paper is to create an aesthetic mold that can be manufactured easily. Simple polygonal patches have been considered for small offsets while cubic rectangular, triangular and n-sided Bezier patches have been discussed to blend the offset planes when the amount of offset is large, leading to larger gaps between planes.
Modeling Variation Propagation of Multi-Station Assembly Systems With Compliant Parts
Authors: Camelio Jaime A. , Hu S. Jack , Ceglarek Dariusz J.
Published: November 2020

Products made of compliant sheet metals are widely used in automotive, aerospace, appliance and electronics industries. One of the most important challenges for the assembly process of such compliant parts is the assembly dimensional quality, which affects product functionality and performance. This paper develops a methodology to evaluate the dimensional variation propagation in a multi-station compliant assembly system based on linear mechanics and a state space representation. Three sources of variation are analyzed, part variation, fixture variation and weld gun variation. The proposed method is illustrated through a case study on automotive body assembly.
An Interactive Aid for Designing and Planning Heterogeneous Layered Prototypes
Authors: Clark Jonathan , Xia Liba , Cutkosky Mark R.
Published: November 2020

We describe a Java process editor to assist designers with the creation of complex, multi-material prototypes via a layered manufacturing process. Designers should generally participate in the manufacturing planning of such parts because many planning decisions are based on functional considerations. For maximum flexibility, the process planning tool should work in a collaborative environment with multiple CAD systems. These considerations have lead us to develop an interactive editor that is built atop a Java agent infrastructure and communicates with commercial CAD systems via their applications programming interfaces.
Strategic Decisions in the Early Stages of Product Family Design
Authors: Maier Jonathan R. A. , Fadel Georges M.
Published: November 2020

The realization that designing products in families can and does have significant technological and economic advantages over traditional single product design has motivated increasing interest in recent years in formal design tools and methodologies for product family design. However, currently there is no guidance for designers in the first key strategic decisions of product family design, in particular determining the type of product family to design. Hence in this paper, first a taxonomy of different types of product families is presented which consists of seven types of product families, categorized based on number of products and time of product introduction. Next a methodology is introduced to aid designers in determining which type of product family is appropriate, based upon early knowledge about the nature of the intended product(s) and their intended market(s). From this information it also follows both which manufacturing paradigm and which fundamental design strategies are appropriate for the product family. Finally the proposed methodology is illustrated through a case study examining a family of whitewater kayaks.
Integrating Market Research With the Product Development Process: A Step Towards Design for Profit
Authors: Gupta Satyandra K. , Samuel Anoop K.
Published: November 2020

This paper describes a systematic approach for integrating market research with the product development process. The following three problems are addressed in this paper. First, a demand estimation algorithm has been developed based on conjoint measurement techniques. Second, an integrated design decision model has been developed. The main components of this design decision model are representation of available design options using AND/OR tree based representation, and an evaluation procedure for evaluating profit resulting from a design option. Third, a heuristic search technique has been developed that makes use of the design decision model to select the design option that maximizes the profit. Integration of market research with the product development process is expected to result in the following two benefits. First, it will reduce the number of design iterations. Second, it will help the design team in finding the most profitable product designs.
An Approach to Decision-Based Design
Authors: Wassenaar Henk Jan , Chen Wei
Published: November 2020

In this paper, we present the importance of using a single-criterion approach to Decision-Based Design (DBD) by examining the flaws and limitations of multicriteria approaches. We propose in this paper an approach to DBD as an enhancement to Hazelrigg’s DBD framework that utilizes the economic benefit to the producer as the single criterion in alternative selection. The technique of Discrete Choice Analysis (DCA) is introduced for constructing a product demand model, which is crucial for the evaluations of both profit and production cost. An academic universal motor design problem illustrates the proposed DBD approach. It appears that DBD, when applied correctly, is capable of unambiguously selecting the preferred alternative in a rigorous manner. Open research issues related to implementing the DBD approach are raised. The focus of our study is on demonstrating the approach rather than the design results per se.
Spatial Reasoning About Mechanical Behaviors
Authors: Kara Levent Burak , Stahovich Thomas F.
Published: November 2020

We describe an approach that uses causal reasoning and geometric reasoning to construct explanations for the purposes of the geometric features on the parts of a mechanical device. To identify the purpose of a feature, the device is simulated with and without the feature. The simulations are then translated into a “causal-process” representation, which allows qualitatively important differences to be identified. These differences reveal behaviors that the feature causes to occur and those it prevents from occurring. The focus of this paper is geometric reasoning techniques that reveal causal relationships between the caused and prevented behaviors. For example, these techniques can determine if a particular caused behavior is responsible for preventing a particular prevented behavior.
An Investigation of Catalogued Product Development Information at a Major Consumer Products Company
Authors: Hoffman Timothy J. , Shooter Steven B. , Szykman Simon , Fenves Steven J.
Published: November 2020

A study of product development practices at a major consumer product manufacturer, referred to as Company X, was undertaken to compare its methods to an earlier effort in modeling the flow of information in product design, referred to as the Design Information Flow Model. The model considers the recognized need in industry for the seamless capture, storage, and retrieval of design information. The research at Company X focused on the front end of product design, that is, the conceptual phase. It was learned that design, as defined by the Information Flow Model, is well represented at the front end of the company’s design process. However, this validation effort succeeded in uncovering certain voids, particularly in later states of the model. It was also learned that product documentation quality and quantity at Company X vary from project to project, indicating an important aspect to consider in our efforts to enhance computer-aided product design is the user.
Modularization to Support Multiple Brand Platforms
Authors: Sudjianto Agus , Otto Kevin
Published: November 2020

Methods to determine acceptable architecture for multiple platforms supporting multiple brands must represent both platform cost saving commonization as well as revenue enhancing brand distinctions. Functional architecting methods determine modularization based upon functional concerns. Brand identity is additionally determined by sensory aesthetics. We introduce three architecting rules to maintain brand identity in platforms. A dominant theme must be ensured on each product of a brand, and this must be transferred to each product’s specifications and aesthetics. Elements critical to brand identity must be made common across all products in a brand. For any platform, brand specific elements must be maintained unique on each product variant. The set of elements not identified as a brand carrier can be made common to a platform. A matrix representation of each platform and its supported brand variants is useful as an architecting tool.
Towards a Model-Based Framework for Linking Design Requirements to the Functional Layout of the Product
Authors: Nilsson Patrik , Fagerström Björn
Published: November 2020

The aim of this paper is to bridge the gap between the requirements and the functional layout of a product during the early phases of product development. During these early phases, it is important to capture the customer’s desires in order to achieve success in the market. A common methodology for this is Quality Function Deployment (QFD). However, we argue that it is important to consider different stakeholder needs and not only the ‘voice of the customer’ to create a well-balanced product. The proposed model uses a QFD with a broader approach in which different stakeholders are considered. The needs from the stakeholders are divided into functional requirements and non-functional requirements (constraints), and linked to the functional layout. The model will support the decision-making process and help the designer balance the interests of different stakeholders and the related functions, resulting in a more balanced product. The model has been applied in an industrial case study.
Functional Modeling Experimental Studies
Authors: Kurfman Mark A. , Stone Robert B. , Rajan Jagan R. , Wood Kristin L.
Published: November 2020

As more design methodologies are researched and developed, the question arises as to whether these new methodologies are actually advancing the field of engineering design or instead cluttering the field with more theories. There is a critical need to test new methodologies for their contribution to the field of design engineering. This paper presents the results of research attempts to substantiate repeatability claims of the functional model derivation method. Three experiments are constructed and carried out with a participant pool that possesses a range of engineering design skill levels. The experiments test the utility of the functional model derivation method to produce repeatable functional models for a given product among different designers. Results indicate the method is largely successful and identify its key strengths as well as opportunities for improvement.
A View of Design Theory and Methodology From the Standpoint of Design Freedom
Authors: Wood William H.
Published: November 2020

While significant progress has been made in design theory and methodology research, no unifying theories have resulted. This paper proposes a preliminary definition of design freedom and uses it as a frame of reference for relating various design theories and methods. This exercise produces two main findings: first, that design freedom is a central concept to most design theories, and second that few design methods deal explicitly with design freedom. A design process model that explicitly includes design freedom is proposed as a unifying framework for design theory and methodology.
Educating for Global Product Realization on a Global Scale
Authors: Horváth Imre , van Breemen Ernest , Dutta Debasish , Yip-Hoi Derek , Kim Jongwon , Lee Kunwoo
Published: November 2020

Three universities on three continents co-operated in teaching global product realization. The Global Product Realization (GPR) course is a highly innovative course in which virtual classrooms and workshops have been formed via ISDN lines, internet facilities and other information technological means representing the state-of-the-technology. This paper gives an insight into the background, the goals, and the implementation of the course. It also outlines the course contents, the layout, and the supporting infrastructure. The GPR course is based on three backbones: academic lectures, company case studies, and a product development project. Parallel to learning of the theoretical and practical backgrounds from academic and industry experts, the international student groups were busy with the development of a global product. It was a coffeemaker for the American, Dutch and Korean markets. The results achieved by the students were presented at the GPR Closing Workshop and Exhibition, where all participants came together to meet the media and the interested parties from academia and industry. The GPR course is a good example of a successful utilization of the opportunities offered by the latest technologies for the implementation of global design and manufacturing in a global environment.
The Effects on Critical Load of Metal-Matrix Composite Plates With a Hole Under In-Plane Loadings
Authors: Okumuş F. , Turgut A.
Published: November 2020

Metal-matrix composite plates consists of several layers of unidirectionally reinforced, fibrous composite laminae which have different in-plane orientations and are bonded together in a certain stacking sequence. Thus, they provide new materials with superior properties of high strength and stiffness.

This study deals with analysis of rectangular metal-matrix composite laminates with circular holes under in-plane static loadings. The first-order shear deformation theory is employed in mathematical formulation. The effects on critical load by hole size, ply lamination geometry, plate thickness ratio, loading types and material modulus ratio have been investigated.

The finite element method is used for finding critical loads. Numerical solutions are given in graphical forms.
Dynamic Track Tension of High Mobility Tracked Vehicles
Authors: Choi J. H. , Ryu H. S. , Bae D. S. , Huh G. S. , Park D. C.
Published: November 2020

In this paper, dynamic track tension for high mobility tracked vehicle is investigated by multibody dynamic simulation techniques. This research focuses on a heavy military tracked vehicle which has sophisticated suspension and rubber bushed track systems. In order to obtain accurate dynamic track tension of track subsystems, each track link is modeled as a body which has six degrees of freedom. A compliant bushing element is used to connect track links. Various virtual proving ground models are developed to observe dynamic changes of the track tension. The dynamic track tensions are monitored at several stationary hull points and points on the track link itself. The effects of pre-tensions, traction forces, turning resistances, sprocket torques, ground profiles, and vehicle speeds, for dynamic responses of track tensions are explored, respectively. Numerical studies of the dynamic track tension are validated against the experimental measurements.
Coupling of Multibody and Control Simulation Tools for the Design of Mechatronic Systems
Authors: Vaculín Ondřej , Krüger Wolf-Reiner , Spieck Martin
Published: November 2020

With the increasing importance of integrating different simulation tools into concurrent design environments, the demands on model complexity and interdisciplinarity have led to a growing number of interfaces between the various tools. This paper presents examples of such interfaces for the connection between multibody simulation and computer-aided control engineering tools. The interfaces introduced in this paper are classified. The application of the different interfaces is presented in two examples. Both are dealing with control of semi-active suspensions, but different methodologies are applied.
Direct Yaw Moment Control for Motorized Wheel Electric Vehicles
Authors: Goodarzi Avesta , Esmailzadeh Ebrahim , Vossoughi G. R.
Published: November 2020

A new control law for direct yaw moment control of an electric vehicle is developed. Although this study is considered as part of a global control system for the traction control of a four motorized wheel electric vehicle, but the results of this study is quite general and can be applied to other types of vehicles. The dynamic model of the system has been analyzed and, in accordance with the optimal control theory, an optimal controller is designed. Two different versions of the control law have been considered and the performance of each version has been separately studied and compared with each other. Finally, the numerical simulation of the vehicle-handling model with and without the use of the optimal yaw moment controller has been carried out. Results obtained indicate that considerable improvement in the vehicle handling has been achieved when the optimal yaw moment controller is engaged.
The Idea of Complementarity in Multibody Dynamics
Authors: Pfeiffer Friedrich
Published: November 2020

Considered in a straightforward manner multibody systems with many multiple unilateral contacts involve a combinatorial problem of huge dimensions, which can only be solved reasonably by the introduction of the complementarity idea. It states that for unilateral contacts either relative kinematics is zero and the corresponding constraint forces are not zero, or vice versa. This leads to a complementarity problem which is somehow related to linear programming problems. Paper discusses the theoretical and practical background.
Lumped-Parameters Brick Element for Modeling Shell Flexible Multibody Systems
Authors: Wasfy Tamer M.
Published: November 2020

An eight-node lumped-parameter brick element, suitable for modeling flexible multibody shell components, is described. The element is composed of twelve truss sub-elements for modeling the membrane and bending modes and six surface shear elements for modeling the shear and warping modes. The element is strategically designed to eliminate locking and spurious modes. Cartesian nodal coordinates are used as degrees-of-freedom with no rotational degrees-of-freedom. This simplifies the coordinate transformations and inertia calculations. A total Lagrangian displacement formulation where the element deformations are measured relative to the unstressed element is employed. The equations of motion are integrated using an explicit temporal integration algorithm. Standard finite element and flexible multibody dynamics test problems are solved to demonstrate the accuracy and robustness of the element. Also, the use of the element in a practical flexible multibody dynamics application, namely, deployment of a large space structure, is demonstrated.
Design of Vibration Absorbers for Step Motions and Step Disturbances
Authors: Fortgang Joel , Singhose William
Published: November 2020

Mechanical systems with flexible dynamics often suffer from vibration induced by changes in the reference command or from external disturbances. The technique of adding a secondary oscillatory system, called a vibration absorber, has proven useful at eliminating vibrations from external disturbances and rotational imbalances. Traditionally, vibration absorbers have been designed for systems subject to sinusoidal or random excitations. Here the applicability of vibration absorbers to systems with step changes in the reference command or similar disturbances is studied. The absorber can be designed with a weighting on peak overshoot and settling time, with the possibility of a nearly 90% improvement in settling time. The performance of this new absorber is compared with previously proposed vibration absorbers.
Cylindrical Workpiece Turning Using Multiple-Cutter Tool Heads
Authors: Gouskov Alexander M. , Paris Henri , Voronov Sergey A. , Batzer Stephen A.
Published: November 2020

The dynamics of turning by a tool head with two multiple-cutter rows is considered. The mathematical model of the process with two commensurate delays with possible cutting discontinuity is analyzed. The domains of dynamic instability are derived, and the influence of technological parameters on the system response is presented. The numeric analysis of system dynamics on discontinuity of cutting is given. In particular, it is shown that there exists specific conditions for given regimes, in which one row of cutters produces an intermittent chip form while the other row produces continuous chips. It is shown that the contribution of parametric excitation by shape roughness of an imperfect (unmachined) cylindrical workpiece surface is not substantial due to the special filtering properties of multiple cutters uniformly circumferentially distributed along the tool head.
On the Transversal Vibrations of a Conveyor Belt Using a String-Like Equation
Authors: Suweken Gede , van Horssen W. T.
Published: November 2020

In this paper an initial-boundary value problem for a linear wave (string) equation is considered. This problem can be used as a simple model to describe the vertical vibrations of a conveyor belt, for which the velocity is small with respect to the wave speed. In this paper the belt is assumed to move with varying speed. Formal asymptotic approximations of the solutions are constructed to show the complicated dynamical behavior of the conveyor belt. It also will be shown that for this problem, the truncation method is not valid on long time scales.
Dynamic Stability of Rotating Abrasive Tool for Deep Hole Honing
Authors: Gouskov Alexander M. , Voronov Sergey A. , Batzer Stephen A.
Published: November 2020

The results of a dynamic stability analysis of a deep hole honing tool are presented. The mathematical model of abrasive machining is analyzed under different support conditions and tool locations on a flexible central shaft. The non-conservative interaction loads of cutting are derived. Complex eigenvalues of system vibrations are calculated. Finally, the influences of system parameters on the stability conditions of dynamic behavior are analyzed.
Combined Parametrical and Transversal Excitation of a Stretched String in an Elastic Medium
Authors: Caswita  , van der Burgh A. H. P.
Published: November 2020

In this paper we consider a two-point boundary alue problem for an integrodifferential equation. This equation can be considered as a nonlinearly perturbed telegraph equation including both parametrical and transversal excitation. The attention will be focused on time-periodic solutions consisting of two modes. The first mode is generated by parametrical excitation and the second one is generated by vertical (transversal) excitation. This interaction of two modes can occur for special combinations of values of two parameters in the equation For the study of time-periodic solutions the averaging method will be used and the stability of the time-periodic solutions will be analyzed in linear approximation.
Forced Response of a SDOF Friction Oscillator Colliding With a Hysteretic Obstacle
Authors: Andreaus Ugo , Casini Paolo
Published: November 2020

The forced dynamics of non-smooth oscillators have not yet been sufficiently investigated, when damping is simultaneously due to friction and impact. Because of the theoretical and practical interest of this type of systems, an effort is made in this paper to lighten the behaviour of a single-degree-of-freedom oscillator colliding with a hysteretic obstacle and excited by an harmonic driving force and by a moving base with constant velocity.

A friction-contact model has been proposed which allows simulating an exponential velocity-dependent friction law, and a deformable (hysteretic) obstacle. This model has been numerically tested via a sample application.
Differential Isolation of Science Instrumentation Packages
Authors: Bower Bruce , Knowles Gareth
Published: November 2020

Vibratory load transmission reduction for precision space optics is demonstrated through a new concept of electronic differential controlled isolation. Lightweight, compact and with very low power consumption, differential controlled isolation can meet the active/passive isolation performance needs in large precision optics, launch system, science instrument modules and observation systems. This includes large optic, interferometric and formation flying platforms. Inexpensive to manufacture, the technology provides flexibility in design to meet many challenges. Although the main thrust of this research was to address OTA truss/ISIM isolation needs, the developed technology is directly applicable to many mission critical needs in launch and deployment of precision space systems.
A Unified Methodology for Modeling Hysteresis in Ferroic Materials
Authors: Smith Ralph C. , Massad Jordan E.
Published: November 2020

This investigation focuses on the development of unified techniques for mathematically modeling the hysteresis and constitutive nonlinearities inherent to ferroelectric, ferromagnetic and ferroelastic materials at moderate to high drive levels. Motivating materials include piezoceramics, relaxor ferroelectrics, magnetostrictives and shape memory alloys, but the modeling approach is sufficiently general to include a large variety of ferroic compounds. The nonlinear and hysteretic behavior of these materials can be attributed to their underlying domain structure and this common ferroic framework is utilized to construct unified constitutive models for the materials. These models are constructed in two steps. In the first, thermodynamic principles are employed to quantify the anhysteretic behavior which would result in the absence of inclusions in the material. In the second step, energy relations are employed to quantify the irreversible and reversible motion of domains walls about pinning sites in the material. The resulting models are formulated as low-order ordinary differential equations. The performance and behavior of the models are illustrated for piezoceramic, magnetostrictive and shape memory compounds.
Parameter Identification for Preisach Models of Hysteresis
Authors: Galinaitis William S. , Joseph Daniel S. , Rogers Robert C.
Published: November 2020

In this paper we consider the abstract mathematical problem of identifying a Preisach operator from idealized training data. We give sufficient conditions on the training data to identify an optimal approximation to the operator. We also show that it is possible to introduce errors if one tries to approximate the operator in the “wrong” function space. We demonstrate the utility of these results using experimental data from SMA wires. We identify the optimal operator using this data and evaluate the performance of the operator in temperature controlled experiments.
Modeling Hysteretic Stress-Strain Relationships With Graphical User Interface
Authors: Zhang Yue
Published: November 2020

The stress-strain relationship of rubber materials manifests as hysteresis loops under finite strain. In this paper, some results from applying an integral formulation that encompasses a memory kernel of time and a nonlinear function of the strain to model extensions of rubber rods are presented. Various experimental data loops are studied. In addition, the author presents a graphical user interface that facilitates the modeling process.
Motion and Vibration Control of Three Dimensional Flexible Shaking Table Using LQI Control Approach
Authors: Hiramatsu Hidefumi , Fuji Daijiro , Seto Kazuto , Watanabe Toru
Published: November 2020

This paper deals with a design procedure of control system for a three-dimensional flexible shaking table.

The shaking table should be less weighted so that actuators require less control forces and higher fidelity to control commands. However, as the weight of shaking table is reduced, the natural frequencies of vibration modes of the table appear on operating frequency region. Such vibration modes get into problem that may cause spillover instability. So, the research purpose is to control such vibration and motion by using the modeling method presented by Seto [1].

Utilizing the model, state equation system model including integrator is composed and feedback controller is designed by using LQI control law. As the system model both includes the multi-degree-of -freedom-structure model and integrator, the designed controller achieves simultaneous motion and vibration control.

Computer simulation and control experiments are carried out and the effectiveness of the presented procedure is investigated.
Actuator Placement for Active Vibration Control Systems With External Excitations
Authors: Yuan Shuqing , Xie Lihua
Published: November 2020

Actuator placement is important to active vibration suppression. It is complex as it concerns many effects. In this paper, a new actuator position optimization criterion is proposed in which the effect of external excitations is considered. The criterion is applied in conjunction with the Independent Modal Space Control method. Effects of different modes are weighted to form a cost function according to their contributions to system dynamic responses, which directly reflect the effects of the external excitations. An example is given to validate the criterion.