bluuebunny/crossref_metadata_2025_split huggingface dataset:
Experimental Evaluation of a Criteria-Based Obstacle Avoidance Scheme
Authors: Harden Troy , Kapoor Chetan , Tesar Delbert 
Published: February 2021

Abstract
Obstacle avoidance allows manipulators to work in cluttered environments without damaging themselves or their environment. It generally involves collision prevention and configuration optimization to avoid obstacles, with collision prevention being the only choice for non-redundant manipulators. In the case of redundant manipulators, one obstacle avoidance scheme uses null-space options for a given end-effector location, and subsequent ranking of these options to select the ‘best’ one based on input criteria. Under this scheme, four obstacle avoidance criteria have been developed. These four (and other non-obstacle avoidance) criteria along with workspace modeling have been implemented as an extension of the OSCAR C++ software library. This library can be used to develop obstacle avoidance applications involving multiple manipulators operating in complex environments. Experimental evaluation of this scheme is conducted on a 17 degree of freedom dual-arm robotic manipulator, and results are presented.
Model Reference Learning Control for Rigid Robots
Authors: Guruprasad K. R. , Ghosal Ashitava 
Published: February 2021

Abstract
The equations of motion of a rigid robot are often known only approximately, as some of the parameters are not known exactly and there are also unmodelled nonlinearities. Most adaptive control schemes can estimate the parameters if the structure of the equations is known, but are not very useful if structure itself is not known.
In this paper we propose a model reference learning control scheme using Adaptive Network based Fuzzy Inference System (ANFIS) for control of rigid robots whose model may have parametric and structural uncertainties. The approximate model of a robot, which may differ very significantly from the actual robot in parametric values and structure, is used as a reference plant and a nonlinear model based controller is designed based on this model. The ANFIS corrector provides an additional correction to control input as a function of the present and desired states of the plant. The error between states of plant and that of reference plant is used to tune the ANFIS corrector.
The proposed control scheme has been implemented for a two-degree-of-freedom serial rigid robot. The results of the simulation experiments carried out show that the proposed control scheme can learn to control the unmodelled dynamics. The ANFIS controller is shown to give improved performance for parameter as well as structural uncertainties.
A New Approach in Solving Bennett Mechanism
Authors: Khan Mahmood A. 
Published: February 2021

Abstract
This paper explores the geometry of the Bennett linkage. Bennett, in the year 1903, invented a 4-R spatial linkage with two remarkable characteristics i.e. with 4 non-parallel and non-concurrent joint axes, has mobility one. In this paper the relationship among the intensities of the twists, i.e. four skew axes of the Bennett, and the perpendicular distances among the opposite skew axes of the Bennett linkage is established. The geometry of the three revolute joint axes of the Bennett Mechanism, one of the classical screw 3-system (Hunt (1978)), are not only skew but are independent to each other.
An Integrated CAD/CAM System for Design and Manufacturing of High-Curvature Surfaces
Authors: Wang Liping , Nair Subramaniam S. 
Published: February 2021

Abstract
This paper presents an integrated CAD/CAM system developed at the City College of the City University of New York (CCNY) for design, analysis and manufacturing of high-curvature surfaces. Surface modeling technique which is characterized by modeling from curvature or slope information, is discussed and practiced to design high-curvature surfaces such as rear-view mirror covers for automobiles. Plastic molding is chosen to manufacture the designed parts. Molding parameters such as entrance position and mold inserts are analyzed and determined using tools such as mold filling analysis (C-FLOW/EZ). Newly modified curvature matching method, together with methods provided by commercial CAM software, are adopted to generate five-axis NC tool path to manufacture the designed mold components. An example on design and manufacturing of a rear-view mirror cover using the integrated CAD/CAM system for high-curvature surfaces is given to illustrate the effectiveness of this system.
Design of a Parallel Manipulator With an Orthogonal Configuration
Authors: Tsai Lung-Wen 
Published: February 2021

Abstract
In this paper, the design of a 6–6 Stewart–Gough platform with an orthogonal configuration is presented. First, a geometric construction of the manipulator is described. Then, it is shown that translational motion of the moving platform can be achieved by programming the limb lengths such that they form three pairs of spatial parallelograms. The Jacobian and stiffness matrices are derived. Finally, it is shown that, at the orthogonal location, the stiffness matrix of the manipulator reduces to a diagonal form. Hence, translational stiffness of the manipulator is completely decoupled from torsional stiffness.
Contention-Free Control of Over-Constrained Variable Geometry Trusses
Authors: Soper R. Randall , Reinholtz Charles F. , Canfield Stephen L. , Williams Robert L. 
Published: February 2021

Abstract
A unified velocity analysis approach for Variable Geometry Trusses (VGTs) is employed to develop a direct strategy for actuator contention avoidance in over-constrained architectures. Techniques of matrix theory are used to meet all boundary and structural constraints simultaneously. The null-space of a square matrix of dimension equal to the number of actuators forms a basis for contention-free trajectories.
Further, the unified velocity analysis procedure, is modified to improve efficiency in the case of open serial chains of truss-type or truss-like manipulators. When applied to over-constrained architectures, an iterative velocity analysis procedure results.
Kinematic Synthesis of Spatial R-R Dyads for Path Following Revisited Using the Rotation Matrix Approach
Authors: Krovi Venkat , Ananthasuresh G. K. , Kumar Vijay 
Published: February 2021

Abstract
We revisit the dimensional synthesis of a spatial two-link, two revolute-jointed serial chain for path following applications, focussing on the systematic development of the design equations and their analytic solution for the three precision point synthesis problem. The kinematic design equations are obtained from the equations of loop-closure for end-effector position in rotation-matrix/vector form at the three precision points. These design equations form a rank-deficient linear system in the link-vector components. The nullspace of the rank deficient linear system is then deduced analytically and interpreted geometrically. Tools from linear algebra are applied to systematically create the auxiliary conditions required for synthesis and to verify consistency. An analytic procedure for obtaining the link-vector components is then developed after a suitable selection of free choices. Optimization over the free choices is possible to permit the matching of additional criteria and explored further. Examples of the design of optimal two-link coupled spatial R-R dyads are presented where the end-effector interpolates three positions exactly and closely approximates an entire desired path.
On the Dynamic Behavior of High Speed Mechanical Systems
Authors: Yuan L. , Rastegar J. 
Published: February 2021

Abstract
This article reports a study of the steady state behavior of mechanical systems with nonlinear dynamics in the presence of dynamic response limitations of the actuation mechanism and in the presence of structural flexibility. In particular, the effects of such dynamic response limitations on the periodicity of the system response are studied and conditions for the existence of periodic solutions are derived. The structural flexibility is shown to increase the number of significant harmonics of the required actuating torques. A number of examples together with computer simulation results verifying the aforementioned results are presented.
Multicriteria Optimization in Product Platform Design
Authors: Nelson Sigurd A. , Parkinson Matthew B. , Papalambros Panos Y. 
Published: February 2021

Abstract
A product platform is a set of common components, modules or parts from which a stream of derivative products can be created. Product platform design requires selection of the shared parts and assessment of the potential sacrifices in individual product performance that result from parts sharing. A multicriteria optimization problem can be formulated to study such decisions in a quantitative manner at the product performance level. Studying the Pareto sets that correspond to various derivative products leads to a systematic methodology for design decision making. A brad-nail gun is used to illustrate the concepts presented.
A Distributed Approach for Accessibility and Maintainability Check With a Manikin
Authors: Chedmail Patrick , Roy Christophe Le 
Published: February 2021

Abstract
The validation of the accessibility, maintainability, mounting/dismantle simulation in a cluttered environment is a key problem during the design process of a mechanical system. On the one hand research in path planning lead to automatic trajectory definition. These systems are really efficient for simple problems. On the other hand direct manipulation is possible thanks to robotic CAD systems. Another direct manipulation is possible with common virtual reality tools that allow the designer immersion in a whole mechanical environment. In such an environment the designer can handle an object in order to check its accessibility. Thanks to the use of a multi-agent architecture we greatly improve the effectiveness of virtual reality tools while coupling algorithmic approaches and direct manipulation. This original method is a solution of a multi-criteria constrained optimisation problem. Theoretical and practical aspects are presented.
Validation of the Tolerance Analysis of Compliant Assemblies
Authors: Sellem Eric , Rivière Alain , De Hillerin Charles André , Clement André 
Published: February 2021

Abstract
Current statistical tolerance analysis of assemblies are generally based on Monte Carlo simulation or Worst Case. The available software tools using this technique model the assembly of rigid parts, by only considering the kinematic laws. Sellem (1998) proposed a linear mechanical model taking both deformation and assembly process into account in the computation of tolerance assemblies of compliant parts. This paper presents the validation of this method by a comparison with measurements performed on an actual assembly of four complex parts. Some improvements in the modeling of the assembly process are also presented and described a sensitivity analysis approach to identify the key characteristics of the assembly.
Position Analysis in Analytical Form of the 3-PSP Mechanism
Authors: Di Gregorio Raffaele , Parenti-Castelli Vincenzo 
Published: February 2021

Abstract
In this paper the direct and the inverse position analysis of a 3-dof fully-parallel mechanism, known as 3-PSP mechanism, is addressed and solved in analytical form. The 3-PSP mechanism consists of two rigid bodies, one movable (platform) and the other fixed (base), connected to each other by means of three equal serial kinematic chains (legs) of type PSP, P and S standing for prismatic and spherical pair respectively. Both the direct and the inverse position analysis of this mechanism lead to non-linear equations that are difficult to solve. In particular, the inverse position analysis comprises different sub-problems which need specific solution techniques. Finally a numerical example is reported.
A Feature Library and an Algorithm for Design of Parts Machinable in Four-Axis CNC Lathes
Authors: Arikan M. A. Sahir , Sander Tolga Ziya 
Published: February 2021

Abstract
A feature library, an algorithm, and an interactive computer program are developed for design of parts machinable in four-axis CNC lathes with milling capabilities. Parts can be checked, visualized, manipulated and modified during or after the design. Previously designed parts can be retrieved and modified for design of new similar parts. The feature library comprises features for turning and related operations; features for planar milling operations to remove material from the cylindrical surface or from the face of the workpiece; features for cylindrical milling operations to remove material from the cylindrical surface of the workpiece; features for boring and related operations; features for single and patterned holes, and hole operations, such as, center drilling, drilling, boring, reaming, groove cutting, tapping, counterboring, countersinking and spotfacing, and features for detail operations such as external and internal threading, external and internal helical groove cutting, knurling and machining of various slots. Parts are designed by using a hybrid algorithm. The main geometry of the part is formed by using the primary operations. For this, parametrically modeled primitives are retrieved from the library, and joined by using union operations. Then, milling, boring and hole operations and details are included again by using parametrically modeled features and subtraction operations as the secondary operations. Blank geometry, which can be a circular, hexagonal, square or rectangular bar; or a part made by forging or casting is defined again by using operations on available primitives. All of the features contain information on process sequencing, cutting tools, tool paths, machining parameters and G-codes. Thus, when the design of the part is completed, information for generation of the CNC program becomes readily available.
Design and Control of Forming Processes Using Optimization Techniques
Authors: Ghouati O. , Lenoir H. , Gelin J. C. , Baida M. 
Published: February 2021

Abstract
The paper deals with the design and control of forming processes. The finite element code used is based on isoparametric shell elements with three or four nodes, the workpiece being considered as a sheet metal. An optimization technique is used in order to achieve the design or the control of the process by determining the optimal process parameters. The criterion used in that purpose can be based on thickness distribution as well as the respect of the final shape desired for the product. Numerical examples are presented as illustration.
Automatic Coordinate Measuring Machine Inspection
Authors: Albuquerque V. A. , Liou F. W. , Agarwal S. , Mitchell O. R. 
Published: February 2021

Abstract
In many industrial applications, such as product prototype development, automation of inspection process can greatly improve product quality and product development cycle, time. This paper discusses a development of a vision aided automatic inspection using Coordinate Measuring Machine (CMM). We seek to integrate the flexibility afforded by computer vision systems with the precision of numerically controlled coordinate measuring machines to achieve a fully automatic and reliable inspection of the industrial parts. The 3-D design information and part specification from computer-aided design file is used for inspection point placement and CMM path planning. The proposed system demonstrates that optimal collision-free inspection paths can be efficiently generated for geometrically complex parts consisting of multiply intersecting features. This is made possible by using iterative subdivision of surfaces for point placement coupled with, efficient 3-D collision avoidance and path planning. The paper discusses different algorithms used, and presents experimental results.
Automated Punch Shape Synthesis for Sheet Metal Bending Operations
Authors: Alva Ujval , Gupta Satyandra K. 
Published: February 2021

Abstract
Sheet metal bending is a process in which bends are formed using a combination of a punch and a die. A very large number of mechanical products such as furniture panels, shelves, cabinets, housing for electro-mechanical devices etc. are created by using the sheet metal bending process. Bending tools need to satisfy the following two criteria: (1) tools should be able to withstand bending forces, and (2) tool shapes should be such that there is no tool-part interference. In this paper, we describe a systematic methodology for automatically synthesizing shapes of bending punches. We create parametric geometric models of punches. These parametric models describe the family of possible punch shapes. Using the part geometry and parametric punch shape models, we automatically generate constraints on tool parameters that eliminate the possibility of part-tool interference. We use mixed integer programming techniques to identify parameters of punch shapes that result in the maximum punch strength. Finally, we perform strength analysis of the designed punch shape to verify that the designed punch shape is capable of withstanding the bending forces.
Manufacturability Analysis for Solid Freeform Fabrication
Authors: Arni R. K. , Gupta S. K. 
Published: February 2021

Abstract
This paper describes a systematic approach to analyzing manufacturability of parts produced using Solid Freeform Fabrication (SFF) processes with flatness, parallelism and perpendicularity tolerance requirements on the planar faces of the part. SFF processes approximate objects using layers, therefore the part being produced exhibits stair-case effect. The extent of this stair-case effect depends on the angle between the build orientation and the face normal. Therefore, different faces whose direction normal is oriented differently with respect to the build direction may exhibit different values of inaccuracies. We use a two step approach to perform the manufacturability analysis. We first analyze each specified tolerance on the part and identify the set of feasible build directions that can be used to satisfy that tolerance. As a second step, we take the intersection of all sets of feasible build directions to identify the set of build directions that can simultaneously satisfy all specified tolerance requirements. If there is at least one build direction that can satisfy all tolerance requirements, then the part is considered manufacturable. Otherwise, the part is considered non-manufacturable. Our research will help SFF designers and process providers in the following ways. By evaluating design tolerances against a given process capability, it will help designers in eliminating manufacturing problems and selecting the right SFF process for the given design. It will help process providers in selecting a build direction that can meet all design tolerance requirements.
PMM: Process Module Methodology for Integrated Design and Assembly Planning
Authors: Bichlmaier Christoph , Grunwald Stefan 
Published: February 2021

Abstract
Competitive products are the key to the success of every company. To resist the pressure of high competition companies must also optimize their processes to an even greater extent.
Apart from the direct production departments such as manufacturing and assembly, where the optimization of production processes have been standard practice for decades, the indirect areas such as product development and planning of production systems are now moving increasingly to center-stage. Alongside the requirement for innovation, these areas are expected to keep to schedule and cost restrictions. But the high degree of complexity of the process steps involved and the difficulty of accurately defining them prevent effective process management in these areas. Experience from industry shows that companies desire a lot of support in these areas.
The following paper describes an innovative methodology for the flexible planning, monitoring and controlling of highly complex dynamic development processes. This methodology, has already proved successful in pilot projects in different industries such as automobile or electrical tool industry.
Layered Manufacturing With Embedded Components: Process Planning Considerations
Authors: Cham Jorge G. , Pruitt Beth L. , Cutkosky Mark R. , Binnard Mike , Weiss Lee E. , Neplotnik Gennady 
Published: February 2021

Abstract
This paper addresses the design and manufacturing of products with embedded components through layered manufacturing processes such as Shape Deposition Manufacturing (SDM). Embedding components allows the creation of novel designs such as “smart” products and integrated assemblies of sensors, actuators and other mechanical components. We present prototypes to illustrate the possibilities for such devices and we address the issues that constrain their process planning. Next, we present a combination of process planning algorithms and manufacturing methods that we have developed to support the design of layered products with embedded components.
Cost Estimation for Process Selection
Authors: Esawi Amal M. K. , Ashby Michael F. 
Published: February 2021

Abstract
In selecting a process to make a given component, it is first necessary to screen available processes to find those which can make the desired shape from the desired material with the desired precision and finish. Commonly, many processes survive this screening, and it is then desirable to rank them approximately so that the most promising are explored first. The natural criterion for ranking is that of relative cost. This paper describes an approximate relative cost model, applicable to all processes, designed to give this approximate ranking. It is based on summing the costs of material, energy, time, capital and other resources. The values for equipment cost, tooling cost and production rate depend on component size and complexity. Approximate scaling methods are used to include these dependencies. The model has been implemented in a Process Selector (the CPS) and fills its intended function adequately.
Incorporating Process Planning Into Conceptual Design
Authors: Feng Shaw C. , Nederbragt Walter W. , Kaing Serge , Sriram Ram D. 
Published: February 2021

Abstract
This paper describes recent developments in the Design and Process Planning Integration (DPPI) project at the National Institute of Standards and Technology (NIST). The project addresses the need for improved communication between design and process planning in the early product design stage. Since major manufacturing costs are committed during product specification and design, it is critical to successfully assess manufacturability and cost as early as possible in the design process. Documenting the DPPI foundation, this paper reviews industry needs for an integrated design and manufacturing environment for rapid product development. Additionally, this paper describes the project’s approach and the current status. Conceptual design and process planning prototype systems, that have been implemented, are also described. Finally, it describes the future direction for developing mechanisms to enable the integration of design and process planning, including information models and language interface specifications.