bluuebunny/crossref_metadata_2025_split huggingface dataset:
Automatic Prototyping of Complex Geometries for Conceptual Design
Authors: Vergeest J. S. M. , Broek J. J. , Tangelder J. W. H. 
Published: April 2021

Abstract
The significance of materialized prototypes from CAD generated mechanical parts has been recognized since more than a decade. Despite the ever increasing quality and speed of graphical visualization methods, solid 3D hard copies from designs remain essential for certain stages in the creation process. Especially during the phase of conceptual geometric design, when alternative shape proposals must be quickly judged, automatic, fast and inexpensive production of replica is of importance. However, for such a kind of prototyping in conjunction with CAD, traditional methods based on CAM and NC technology turn out not adequate. To support conceptual design, several extensions and optimizations, mainly in the software area, need to be effected. In this paper an autonomous NC-milling process generator TLCOR is presented. It evaluates and analyzes surface/solid models based on NURBS, determines the physical constraints of the 3D milling devices (represented in a technical database) and finally produces an ISO-standard control statement sequence. The system selects the appropriate machining method (parametric and/or geometric algorithms) and tools, and breaks up the process into different stages of non-planar path planning with interference avoidance. The user will never be confronted with any aspect concerning the NC. The designer only needs to express his or her wish to obtain a milled copy of the actual CAD model. Extension of TLCOR to shape models defined neutrally (STEP/PDES based) and to multi-axis and robot milling is in progress.
The M-Space Theory of Tolerances
Authors: Turner Joshua U. , Wozny Michael J. 
Published: April 2021

Abstract
A rigorous mathematical theory of tolerances is an important step toward the automated solution of tolerancing problems. This paper develops a mathematical theory of tolerances in which tolerance specifications are interpreted as constraints on a normed vector space of model variations (M-space). This M-space provides concise representations for both dimensional and geometric tolerances, without deviating from the established tolerancing standards. This paper extends the authors’ previous work to include examples of geometric orientation and form tolerances. We show that the M-space theory supports the development of effective algorithms for the solution of tolerancing problems. Through the use of solid modeling technology, it is possible to automate the solution of such problems.
Generation and Modification of Non-Uniform B-Spline Surface Approximations to PDE Surfaces Using the Finite Element Method
Authors: Brown Joanna M. , Bloor Malcolm I. G. , Bloor M. Susan , Wilson Michael J. 
Published: April 2021

Abstract
A PDE surface is generated by solving partial differential equations subject to boundary conditions. To obtain an approximation of the PDE surface in the form of a B-spline surface the finite element method, with the basis formed from B-spline basis functions, can be used to solve the equations. The procedure is simplest when uniform B-splines are used, but it is also feasible, and in some cases desirable, to use non-uniform B-splines. It will also be shown that it is possible, if required, to modify the non-uniform B-spline approximation in a variety of ways, using the properties of B-spline surfaces.
QUINT: A Problem-Solving Strategy for Mechanical System Conceptual Design: Part I — Environment, Function, Structure, and Parameter
Authors: Qun Wang , Haibin Yang , Ji Zhou , Jun Yu 
Published: April 2021

Abstract
Mechanical system conceptual design, sometimes termed mechanical system scheme design or preliminary mechanical system design, is the key link of mechanical system design, and also the bottleneck of integrated CAD / CAM [1][2][3]. Therefore, it is important to automize this part of work to promote the quality of mechanical system design and the extent of product design automation.
This paper will discuss in detail a problem-solving strategy for mechanical system conceptual design — QUINT. It devides the conceptual design into five stages: (1) environment ▸ function; (2) function ▸ structure; (3) structure ▸ parameters; (4) parameters ▸ analysis; (5) analysis ▸ evaluation and decision. QUINT has already been successfully applied in CDESTOOL (Conceptual Design Expert System TOOL). With this tool, three practical systems have been developed: industrial turbine general scheme design expert system (TDES), wheel loader general scheme design expert system (WLDES), and milling-boring machining center scheme design expert system (MDES). The result is fairly satisfactory.
An Active Suspension Strategy Using State Reconstruction
Authors: Warner P. K. , Vanderploeg M. J. , Shannan J. E. 
Published: April 2021

Abstract
Many studies have shown that active suspensions using full state feedback can significantly improve the ride performance of ground vehicles. Using a seven degree of freedom vehicle model and a Kalman filter, this paper investigates the effects of reduced state feedback on active and semi-active suspension systems. Particular attention is given to control of pitch motion, which is usually considered to be the most uncomfortable of rigid body motions. The effects of phase differences between the tires is presented using frequency response surfaces.
The Kalman filter, which reconstructs the state variables from a reduced set of observed variables, yields improvements in ride which compare well with the ideal active suspension without the need to measure all states. The Kalman filter system with active dampers instead of ideal actuators also yields ride improvements approaching the ideal systems.
Optimal Packaging of Complex Parametric Solids According to Mass Property Criteria
Authors: Landon Mark D. , Balling Richard J. 
Published: April 2021

Abstract
A solution to the 3-D optimal packaging problem is presented. The positions and orientations of arbitrarily shaped objects in arbitrarily shaped 3-D containers are found. Mass property and spatial criteria are addressed. The robustness and speed of the optimal packaging solution is increased by supplying explicit gradients for the optimization search routines.
Experimental Validation of a Dynamic Simulation
Authors: Yae K. Harold , Chern Su-Tai , Hwang Howyoung 
Published: April 2021

Abstract
Using forward and inverse dynamic analysis, the dynamic simulation of a backhoe has been compared with experiments. In the experiment, recorded were the configuration and force histories; that is, velocity and position, and force output from the hydraulic cylinder-all were measured in the time domain. When the experimental force history is used as driving force in the simulation, forward dynamic analysis produces a corresponding motion history. And when the experimental motion history is used as if a prescribed trajectory, inverse dynamic analysis generates a corresponding force history. Therefore, these two sets of motion and force histories — one set from experiment, and the other from the simulation that is driven forward and backward with the experimental data — are compared in the time domain. The comparisons are discussed in regard to the effects of variations in initial conditions, friction, and viscous damping.
A Cross-Sectional Shape Multiplier Method for Two-Level Optimum Design of Frames
Authors: Zhao Wenzhong , Azarm Shapour 
Published: April 2021

Abstract
In this paper, a new method for optimum design of frame structures is presented. The method is based on a hierarchical decomposition of the structure into two-levels, namely, the bottom- and the top-level. The bottom-level consists of several subproblems each dealing with the cross-sectional sizing of a given frame-element. The top-level consists of one subproblem which is formulated for configuration design of the frame structure. Since there may be a large number of frame elements, a new shape multiplier method has been developed to simplify the formulation of the bottom-level subproblems. Furthermore, a two-level solution procedure has been developed which first solves the bottom-level subproblems based on their monotonicity analysis. It then solves the top-level subproblem as it coordinates, based on a linear approximation, the solutions to the bottom-level subproblems. Three examples with increasing degree of difficulty are presented to demonstrate the effectiveness of the method.
Shape Synthesis and Optimization Using Intrinsic Geometry
Authors: Tavakkoli Shahriar , Dhande Sanjay G. 
Published: April 2021

Abstract
The present paper outlines a method of shape synthesis using intrinsic geometry to be used for two-dimensional shape optimization problems. It is observed that the shape of a curve can be defined in terms of intrinsic parameters such as the curvature as a function of the arc length. The method of shape synthesis, proposed here, consists of selecting a shape model, defining a set of shape design variables and then evaluating Cartesian coordinates of a curve. A shape model is conceived as a set of continuous piecewise linear segments of the curvature; each segment defined as a function of the arc length. The shape design variables are the values of curvature and/or arc lengths at some of the end-points of the linear segments. The proposed method of shape synthesis and optimization is general in nature. It has been shown how the proposed method can be used to find the optimal shape of a planar Variable Geometry Truss (VGT) manipulator for a pre-specified position and orientation of the end-effector. In conclusion, it can be said that the proposed approach requires fewer design variables as compared to the methods where shape is represented using spline-like functions.
Design Sensitivity Analysis of Machine Tool Spindle and Support System
Authors: Chandrupatla Tirupathi R. 
Published: April 2021

Abstract
The problem of selecting the bearing spacing for a machine tool spindle is considered. The main objective is to choose this spacing value at the design stage for minimizing the workpiece cylidricity error. The equations are derived in a general setting and optimum values are computed. The method presented can be extended to more complex spindle designs.
3-D Elasto-Plastic Contact Finite Element Analysis for Bearings Design
Authors: Shigang Wang , Jun Yu , Ji Zhou , Mingzhang Li 
Published: April 2021

Abstract
In this paper, A 3-D elasto-plastic contact problem in bearings is studied by Finite Element Method (FEM). A computer program has been developed for this purpose. A trial-error method is employed to cope with the geometrical nonlinearity and a tangential stiffness method is employed to tackle the material nonlinearity appeared in elasto-plastic contact problems. A frictionless contact problem of roller bearings is analysed, the result reveals that in 3-D elasto-plastic state the trend of the contact surface pressure distribution is similar to Hertz problem’s but flater.
Integrating Parametric Geometry, Features, and Variational Modeling for Conceptual Design
Authors: Keirouz Walid , Pabon Jahir , Young Robert 
Published: April 2021

Abstract
We describe an architecture for conceptual mechanical modeling. It combines tools for parametric geometry and variational modeling using a feature-based representation. Parametric geometry allows designers to represent families of components as a single parameterized model. Variational modeling allows designers to model mechanical concepts analytically using equational constraints, and to evaluate competing alternatives common during conceptual design. Feature definition facilities allow designers to build libraries of frequently used mechanical components, by collecting interacting components into single higher level entities (features), and defining ways to interact with them.
All of these capabilities are needed for conceptual design, and play complementary roles. Integrating them, and clarifying their inter-relationships, is essential to building an architecture supporting conceptual design. To this end, we have implemented this architecture in an experimental CAD system.
Representing and Recognizing Features in Mechanical Designs
Authors: Finger Susan , Safier Scott A. 
Published: April 2021

Abstract
When experts view an object, they perceive it in terms of their own expertise. For example, manufacturers see features that affect the processes used to fabricate a part, while structural engineers see sources of stresses and other features that tend to reduce the life of a part. Features can be geometric, such as slots or chamfers; they can be quantitative, such as distances between holes; they can be functional, such as alignment; or they can be qualitative, such as a rough surface finish. Research in feature-based design systems for mechanical designers has been motivated by the realization that geometric models represent the design in greater detail than can be utilized by designers, process planners, assembly planners, or by systems that emulate these activities. Features provide abstractions to facilitate the creation, representation, and analysis of designs.
Our goal is to enable designers to compose mechanical designs from high-level features that embody functional and geometric properties. In addition, we want to provide designers with feedback on the manufacturability, assemblability, functionality, cost, etc. of the design as it evolves. To support this process in an intelligent CAD environment requires the integration of geometric models, analysis tools, and synthesis tools so that all aspects of the design can be considered while it is in progress. We are developing a design environment based on a shared representation of the design in which we can extract and reason about features of the design from different perspectives.
Our approach is to represent both the design and the features using graph grammars. By representing the features using the same grammar as the design, we can recognize features by parsing a feature against the graph that represents the design. We are exploring grammars for behavior as well as geometry in order to provide a link between behavioral and geometric representations. In this paper, we focus on the representation and recognition of features.
Heuristic Design of a Material Processing Component
Authors: Jamalabad Vikram R. , Langrana Noshir A. , Jaluria Yogesh 
Published: April 2021

Abstract
The main thrust of this research is in developing a knowledge-based system for the design of a mechanical engineering process. The study concentrates on developing methodologies for initial design and redesign in a qualitative format. The component selected is a die for plastic extrusion. A design algorithm using best first heuristic search and expert knowledge, both in procedural and declarative form, forms the core of the process. Initial design and redesign methodologies are presented that can enable efficient design of a component using expert knowledge. Some generality has been accomplished by the implementation of the techniques to dies of different cross sectional shapes. The software is written in Lisp within an object oriented software package using analysis modules written in C.
Back to the Drawing Board?: Computer-Mediated Communication Tools for Engineers
Authors: Jakiela Mark J. , Orlikowski Wanda J. 
Published: April 2021

Abstract
This paper describes an exploratory research study that attempted to determine the nature of computer-mediated information that would be exchanged by engineers engaged in a process of product design and manufacture. The results suggest that computer-mediated communication tools supporting asynchronous, written modes of information exchange, are likely to have little utility for engineers engaged in design and manufacture. Substantial augmentation of these tools will be necessary before their wide-spread adoption and use by engineers can be expected.
Design Evolution Management: A Methodology for Representing and Utilizing Design Rationale
Authors: Thompson James B. , Lu Stephen C.-Y. 
Published: April 2021

Abstract
In conventional design practice, a detailed product description is the end-result of a design process. Usually these detailed product descriptions do not contain information linking their heritage from early-stage abstract product descriptions or the particular influence of different life-cycle perspectives. This “missing” information, a description of the multi-staged and multi-perspective design process, is termed a design evolution, and is a representation of the design rationale for a product description. This research focuses on the development of a methodology for Design Evolution Management, i.e. techniques for representation and subsequent utilization of a design evolution during a design process. Within this methodology, a design evolution is represented both at strategic and tactical levels. A prototype computer-based design environment called AIDEMS, based on this design methodology, has been built and is being tested in several design domains. This design environment provides design engineers a platform for expressing their design strategies and tactics and uses Artificial Intelligence programming techniques enabling semi-automated design assistance for: resource scheduling, explanation of design assertions, execution of design revisions, design inconsistency detection, and exploration of design alternatives.
Constraint Absorption and Relaxation Using a Design History
Authors: Meehan Edmund J. , Brown David C. 
Published: April 2021

Abstract
A simple mechanism has been implemented and demonstrated within a routine design expert system. It has a limited ability to adjust design constraints based on experience within the domain. The mechanism is activated in response to noticing an extended run of either constraint failures or constraint successes. It reasons about the validity of either relaxing or absorbing a constraint. This process is referred to as Constraint Absorption. We hope to improve the performance of the expert system by reducing the incidence of repeated constraint failure, and by eliminating redundant constraints.
Simulation of Probabilistic Wind Loads and Building Analysis
Authors: Shah Ashwin R. , Chamis Christos C. 
Published: April 2021

Abstract
Probabilistic wind loads likely to occur on a structure during its design life are predicted. This article describes a suitable multifactor interactive equation (MFIE) model and its use in the Composite Load Spectra (CLS) computer program to simulate the wind pressure cumulative distribution functions on four sides of a building. The simulated probabilistic wind pressure load was applied to a building frame, and cumulative distribution functions of sway displacements and concepts of reliability were demonstrated by computing the probability of overturning using NESSUS (Numerical Evaluation of Stochastic Structure Under Stress), a stochastic finite-element computer code. The geometry of the building and the properties of building members were also considered as random in the NESSUS analysis. The uncertainties of wind pressure, building geometry, and member section property were quantified in terms of their respective sensitivities on the structural response.
Incorporating Finite Element Analysis Into Component Life and Reliability
Authors: August Richard , Zaretsky Erwin V. 
Published: April 2021

Abstract
A method for calculating a component’s design survivability by incorporating finite element analysis and probabilistic material properties was developed. The method evaluates design parameters through direct comparisons of component survivability expressed in terms of Weibull parameters. The analysis was applied to a rotating disk with mounting bolt holes. The highest probability of failure occurred at, or near, the maximum shear stress region of the bolt holes. Distribution of material failure as a function of Weibull slope affects the probability of survival. Where Weibull parameters are unknown for a rotating disk, it may be permissible to assume Weibull parameters, as well as the stress-life exponent, in order to determine the effect of disk speed on the probability of survival.
Extensions to the Taguchi Method of Product Design
Authors: Otto Kevin N. , Antonsson Erik K. 
Published: April 2021

Abstract
The Taguchi method of product design is an experimental approximation to minimizing the expected value of target variance for certain classes of problems. Taguchi’s method is extended to designs which involve variables each of which has a range of values all of which must be satisfied (necessity), and designs which involve variables each of which has a range of values any of which might be used (possibility). Tuning parameters, as a part of the design process, are also introduced into Taguchi’s method. The method is also extended to solve design problems with constraints, invoking the methods of constrained optimization. Finally, the Taguchi method uses a factorial method to search the design space, with a confined definition of an optimal solution. This is compared with other methods of searching the design space and their definition of an optimal solution.
Capturing and Using Designer Intent in a Design-With-Features System
Authors: Nielsen Eric H. , Dixon John R. , Zinsmeister George E. 
Published: April 2021

Abstract
The goal of “intelligent” computer-aided-design (CAD) systems is to provide greater support for the process of design, as distinguished from drafting and analysis. More supportive design systems should provide a quick and simple means of creating and modifying design configurations, automating evaluation procedures (e.g., for manufacturing), and automating interfaces to analysis procedures.
In this paper we are concerned with the issues of representing in-progress designs so that such goals can be met. A feature-based representation is proposed in which features are defined as possessing not only form but also certain designer intentions regarding geometric relationships. A working experimental version of a design-with-features system using this representation for thin-walled components illustrates its use in composing a design as a configuration of feature-forms, in modifying the design geometry through automatic, intelligent incorporation and propagation of designer-initiated geometry changes, and in providing for the generation of user-defined features. In contrast to constraint-driven simultaneous equation solving methods, this system uses an intent-driven knowledge-based method to propagate and incorporate geometry modifications not only in fully-constrained designs, but also in over- and under-constrained designs. Issues of manageability, extensibility, and computationally efficiency were considered in the development of the core services of the system.
Life-Cycle Serviceability Design
Authors: Gershenson John , Ishii Kosuke 
Published: April 2021

Abstract
This research seeks to develop a systematic methodology to balance the serviceability, reliability, and modularity (SRM) of a design with other life-cycle costs. While design for assembly (DFA) and modular designs are stressed, SRM’s effects on post manufacturing life-cycle issues are often bypassed. In particular, a design without adequate consideration for serviceability could seriously affect service costs and customer satisfaction. This paper develops a systematic method to deploy the serviceability design guidelines during early stages of design. Our study, service mode analysis (SMA), involves a consistent representation of design rules, failure and service frequency data, and life-cycle service cost. This paper defines the steps used to complete the service mode analysis and proposes a means of expressing serviceability both quantitatively and qualitatively. The paper also shows a method to examine tradeoffs between serviceability costs and other life-cycle costs.