bluuebunny/crossref_metadata_2025_split huggingface dataset:
Kinematic Passive Correction of Errors in Active Surfaces
Authors: Smith David R. 
Published: March 2021

Abstract
The advancing requirements of instrumentation in astronomy has led to the development of telescopes with segmented active surfaces. In such telescopes, movable segments are controlled together to maintain the correct figure of the reflecting surface. This paper investigates telescope active surfaces by representing each movable segment as a 3-degree of freedom (DoF) parallel manipulator of the type described by Lee and Shah (1988a, 1988b). The workspace of this manipulator is examined for two types of actuator mounting geometries. In the first case, pin joint connections are placed at the base and ball joints at the end-effector. In the second case, the joints are reversed. Following a general investigation, the results are specialized to reflect the behavior of small motions, as active surfaces require only small adjustments. Finally, the effects of the kinematics on the performance of an example surface are determined. The analysis reveals that placing the ball joint connections at the base provides a passive correction of uncontrolled states in the surface.
Automatic Generation of the Input-Output Equations of Planar Mechanisms
Authors: Kanberoglu Kunter A. , Soylu Resit 
Published: March 2021

Abstract
In this article, a methodology, which yields (in closed-form) the functional relation between “any” two joint variables of a one degree-of-freedom planar mechanism, is developed. For instance, the transmission angle and crank-rotatibility synthesis algorithms (Soylu, 1993; Soylu and Kanberoğlu, 1993) require such a generic input-output equation. The equation is obtained in an optimal manner which minimizes the computational effort associated with it. The tools of theory of elimination and symbolic manipulation are also used in the developed method.
Change-Point Configurations of RSSR and Other Bimodal Linkages
Authors: Ting Kwun-Lon , Dou Xiaohong 
Published: March 2021

Abstract
In this article, an analytical method is developed for finding change-point positions of RSSR and other bimodal linkages. At a change-point position, the input or output discriminant function and its derivative with respect to the input angle are equal to zero. The method is demonstrated in studying the effect of the skew distance between the joint axes to the existence of change-positions and offering the first successful systematic search of general RSSR change-point linkages. Like planar four-bar linkages, the issue of change-point linkages is pivotal to the understanding of the mobility and assemblability of the RSSR linkage and other bimodal linkages.
The Linear Representation of the Screw Triangle: A Unification of Finite and Infinitesimal Kinematics
Authors: Huang Chintien , Chen Chien-Ming 
Published: March 2021

Abstract
This paper presents the linear representation of the screw triangle. The resultant twist of two finite twists is shown to be a linear combination of five screws. The linear representations of all degenerate screw triangles are also derived. The limiting cases of these results of finite displacements confirm the theory of screws in infinitesimal kinematics. The finite kinematic analysis of multi-link serial chains is performed by using the linear representation of the screw triangle to demonstrate a unification of finite and infinitesimal kinematics.
Optimum Design of a Spatial 7R Homokinetic Linkage
Authors: Jiyuan Zhang , Shoufan Shen 
Published: March 2021

Abstract
In this paper, an optimum design method based on orthogonal tables is applied to the design of a spatial 7R homokinetic linkage. An optimum design problem is first formulated; then, an optimum design, with a coefficient of speed fluctuation δ &lt; 2.52%, has been achieved, as reported here.
Numerical Phenomena of a Spatial Mechanism With Clearances
Authors: Jianling Zhang , Zhe Li , Shixian Bai 
Published: March 2021

Abstract
The general mechanical model of C pair with clearances is set up and used to derive the differential equation of motion of a RSCR mechanism with clearance at C pair in this paper. The numerical results are analysed and compared with the dynamic responses of the nominal RSCR mechanism. Chaotic phenomena can be seen in the numerical results, which indicate that the steady state responses may not be achievable for spatial mechanisms with clearance connections.
A Symbolic-Numerical Approach for the Synthesis of Planar Rigid-Body Guidance
Authors: Chen Yong , Fu Jinyuan 
Published: March 2021

Abstract
Based on the pole method and the computer symbolic manipulating technique, a fourth order algebraic equation with single variable has been derived for the closed form solution of planar rigid-body guidance. The newly developed method eliminates the requirement of sloving system of nonlinear equations. All solutions of the problem can be obtained directly and easily without the need of initial values. A numerical example is given demonstrating the efficiency and advantages of the method.
An Efficient Algorithm for Computing the Steady-State Dynamic Response of High-Speed Mechanisms
Authors: Selstad Tyler J. , Farhang Kambiz 
Published: March 2021

Abstract
An efficient method for obtaining the steady-state response of linear systems with periodically time varying coefficients is developed. The steady-state solution is obtained by dividing the fundamental period into a number of intervals and establishing, based on a fourth-order Rung-Kutta formulation, the relation between the response at the start and end of the period. Imposition of periodicity condition upon the response facilitates computation of the initial condition that yields the steady-state values in a single pass; i.e. integration over only one period. Through a practical example, the method is shown to be more accurate and computationally more efficient than other known methods for computing the steady-state response.
Stiffness Model of Coiled Springs Including the Axial Asymmetry due to the Helical Geometry
Authors: Lindkvist Lars 
Published: March 2021

Abstract
The stiffness of a short section of a coiled spring is derived by writing the elastic energy in the spring wire, considering its actual geometric form, and then applying the Castigliano theorem. The resulting linear stiffness model includes the effects of pitch, curvature of the wire and distortion due to normal and transverse forces in the wire. Further, the starting and ending points of the spring wire are taken into consideration.
This stiffness model is used to derive the locally linearized stiffness matrix for a complete coiled spring that is laterally loaded. The stiffness matrix is evaluated by first calculating the non-linear deformation for a given external load and then linearizing the analysis about that equilibrium point. The deformation is calculated by summing the contributions from a number of small spring elements for which the deformations are considered to be linear.
The natural frequencies of a mechanical system consisting of a rigid body and a laterally loaded spring are calculated and compared with experimental results. These experiments clearly verify the proposed theoretical stiffness matrix for the complete spring and detect the rotational asymmetry of the spring.
An Automated System for Cam Design and Manufacture
Authors: Tsai Wu-Jung , Lee Jyh-Jone 
Published: March 2021

Abstract
In this paper, we developed an automated system for the design and manufacture of three-dimensional cams. This system incorporates the computer-aided design, manufacturing and inspection three sequences into one automated process. First, a computer package employing the theory of gearing is developed for synthesizing and animating cam mechanisms. Then, a module for generating NC programs for a five-axis CNC machine to manufacture spatial cams is established. Finally, a computer-aided inspection system for measuring cam profile is introduced. This automated CAD/CAM/CAI system is illustrated with an example on the design of a roller gear cam.
Computerized Design and Generation of Low-Noise Helical Gears With Modified Surface Topology
Authors: Litvin F. L. , Chen N. X. , Lu J. , Handschuh R. F. 
Published: March 2021

Abstract
An approach for design and generation of low-noise helical gears with localized bearing contact is proposed. The approach is applied to double circular arc helical gears and modified involute helical gears. The reduction of noise and vibration is achieved by application of a predesigned parabolic function of transmission errors that is able to absorb a discontinuous linear function of transmission errors caused by misalignment. The localization of the bearing contact is achieved by the mismatch of pinion-gear tooth surfaces. Computerized simulation of meshing and contact of the designed gears demonstrated that the proposed approach will produce a parabolic transmission errors function when misalignment is present. Numerical examples for illustration of the developed approach are given.
Concurrent Multiaxial Damper Design for Damping Augmentation of a 3-Cable Suspension System
Authors: Yang Li-Farn 
Published: March 2021

Abstract
An approach to the concurrent design of the multiaxial inertial dampers for damping augmentation of the Multi-Body Dynamic (MBD) system is presented. The system considered herein features a 3-cable mechanism that acts as a suspension system equipped with the 3-axial inertial dampers atop a stable platform. Such a damping device has been introduced as an application in eliminating the attendant vibrations of the 3-cable suspension system for use in the preflight validation testing of flexible space structures. The primary objective is aimed at optimally designing three independent dampers in a concurrent procedure, in which an optimization is developed to minimize mean-squared motion in an attempt to augment damping of the 3-cable suspension system against the pendulum vibrations. This leads to the simultaneous tuning of three inertial dampers without any loss of cross-coupled damping effect from the MBD standpoint. Comparison of the simulated-time histories for the cases of damped and undamped vibrations is presented to show the effectiveness of the present approach.
Computer-Aided Sketching of Epicyclic-Type Automatic Transmission Gear Trains
Authors: Chatterjee Goutam , Tsai Lung-Wen 
Published: March 2021

Abstract
The enumeration of epicyclic gear mechanisms in the form of graphs gives rise to the need of a methodology for reverse transformation, that is, for constructing the mechanisms from graphs. This paper addresses the issue by discretizing an epicyclic gear mechanism into Fundamental Geared Entities. Further, these geared entities are shown to be a conglomeration of four primitives; namely, the carrier, sun, ring, and the planet gear. An algorithm is formulated to create the entities from a graph by using these primitives. The entities are then connected together to form a mechanism.
An Efficient Method for Evaluating Steady-State Response of Periodically Time-Varying Linear Systems, With Application to an Elastic Slider-Crank Mechanism
Authors: Farhang Kambiz , Midha Ashok 
Published: March 2021

Abstract
This paper presents the development of an efficient and direct method for evaluating the steady-state response of periodically time-varying linear systems. The method is general, and its efficacy is demonstrated in its application to a high-speed elastic mechanism. The dynamics of a mechanism comprised of elastic members may be described by a system of coupled, inhomogeneous, nonlinear, second-order partial differential equations with periodically time-varying coefficients. More often than not, these governing equations may be linearized and, facilitated by separation of time and space variables, reduced to a system of linear ordinary differential equations with variable coefficients. Closed-form, numerical expressions for response are derived by dividing the fundamental time period of solution into subintervals, and establishing an equal number of continuity constraints at the intermediate time nodes, and a single periodicity constraint at the end time nodes of the period. The symbolic solution of these constraint equations yields the closed-form numerical expression for the response. The method is exemplified by its application to problems involving a slider-crank mechanism with an elastic coupler link.
MinnSketch©: A Graphic Kinematic and Dynamic Analysis Tool for Planar Mechanism Design
Authors: Ho Chengta , Erdman A. G. , Riley Donald R. 
Published: March 2021

Abstract
MinnSketch© is a new conceptual design package for the generation of planar mechanisms. This program is implemented in C and runs in an X/Motif graphic environment. MinnSketch allows users to intuitively construct a mechanism from scratch and to rapidly develop the conceptual model to a workable solution. The purpose of developing this program was to create an intuitive design tool, so the user interface was designed to closely model the real-world environment. By directly manipulating the graphic conceptual model intuitively with the aid of the feedback from the simulation and analysis results, users can thoroughly understand their designs and thus can increase their productivity.
The Automatic Sketching of Planar Kinematic Chains
Authors: Zhixing Wang , Wenhui Li , Huamin Li , Ruimin Wu 
Published: March 2021

Abstract
This paper presents a method for the automatic generation of independent loops and peripheral loops of planar kinematic chains. In order to implement this method, three laws are brought out and some new concepts, for instance, same-position-link, similar-loop, loop-link-vector, loop-joint-vector, loop-link matrix and loop-joint matrix, etc., are defined. Finally, planar kinematic chains are sketched automatically according to these loops generated.
Computer Aided Design for High Mechanical Efficiency of Wolfrom Type Speed Reducers
Authors: Orlandea Cosmin , Tataru Ovidiu 
Published: March 2021

Abstract
Wolfrom type planetary speed reducers are complex planetary transmissions, formed of three simple planetary mechanisms that have the same carrier H.
The main characteristic of this kind of reducers is the large transmission reduction ratio (usually by a factor of 100 ... 300), obtained with a relatively small sized reducer.
Generally, high transmission ratio reducers have the capability to output high torque. Considering the fact that their physical size is small, there are high normal loads between the teeth of the component gears and in the bearings, increasing the internal losses of the system.
The object of this paper is to help the designer of this type of speed reducers to find the limits of the transmission ratio corresponding to an acceptable mechanical efficiency and size.
We have expressed all the relations as functions of only three variables (z1, a and δ), that best define the integer type of relations involved in this paper. Based on these relations, we have created a computer program to optimize the value of the total mechanical efficiency of the planetary train.
On the Mobility of Compliant Mechanisms
Authors: Murphy Morgan D. , Midha Ashok , Howell Larry L. 
Published: March 2021

Abstract
The topological synthesis for a compliant mechanism leads to a very large number of design options from which to select a final design. Therefore, an evaluation of a mechanism’s ability to meet selected criteria provides a means of reducing a large number of possible designs to a smaller set of acceptable designs. One criterion deals with a mechanism’s potential mobility. For mechanisms containing flexible members, the response to inputs, in general, is comprised of both rigid-body and elastic deflections of their members. This paper deals primarily with the development of a technique for the determination of mobility characteristics of compliant mechanisms, employing a mathematical model previously developed for compliant mechanisms.
A Linear Scheme for the Displacement Analysis of Micropositioning Stages With Flexure Hinges
Authors: Her I. , Chang J. C. 
Published: March 2021

Abstract
In this paper we present an analytical scheme for the displacement analysis of micropositioning stages with flexure hinges. The proposed scheme is based on linearization of the geometric constraint equations of the stage structure. A design chart for evaluating the stiffness of the flexure hinge is also presented in this paper. This chart provides more accurate estimations than the design formula presently in use. The proposed linear scheme is general, easy to use, yet capable of obtaining results close to those obtained from the finite element analysis.
A Modular, Long-Reach, Truss-Type Manipulator for Waste Storage Tank Remediation
Authors: Salerno Robert J. , Reinholtz Charles F. 
Published: March 2021

Abstract
This paper will introduce a new type of modular manipulator system that is particularly well suited for performing long-reach, high-payload operations such as waste storage tank remediation. These new capabilities are achieved by employing an “all-truss” design in which discrete truss modules are used to construct a reconfigurable manipulator system. Each module of the manipulator is either a static truss “link” or one of several possible Variable Geometry Truss “joints.” This paper presents background information, system requirements, a description of the individual components used to construct the manipulator, and an overview of the kinematic analysis algorithms developed to address the redundant nature of the manipulator.
Identification for Manipulators With Joint Compliances and Link Deflections
Authors: Lin Cheng Y. , Chew Meng-Sang , Everett Louis J. , Juang Jer-Nan 
Published: March 2021

Abstract
An iterative forward transformation algorithm is developed to compute the pose at the end effector of a manipulator when subjected to joint compliances and link deflections. The algorithm is based on the homogeneous transformation matrices and a gravity term associated with each joint. In addition, an identification algorithm has been developed to determine the kinematic and structural parameters of a flexible manipulator used in the forward transformation algorithm. As most of the links of a manipulator are not simple beams, the identification algorithm is particular useful to obtain a set of correct parameters. Results of the simulation tests for a 6-DOF robot are shown to check these algorithms.
3-D Object Recognition Techniques: A Survey
Authors: Telagi Mruthyunjaya S. , Soni Athamaram H. 
Published: March 2021

Abstract
Visual systems for inspection and material handling are becoming popular in manufacturing. In last decade visual systems have made commendable progress, but most of the success in their application has been achieved in controlled working environment. Research work is going now in designing intelligent visual systems which can respond to changing working environment. Following is the discussion of different visual systems. Where ever possible we have discussed their merits and limitations. Even though research in this area looks promising still lot of work has to be done to build real intelligent system to satisfactorily apply in the real world.
Automation of a Hydraulic Hose Assembly Plant
Authors: Tennyson Stephen A. , Mehta Sudhir I. , Lentner Bruce J. 
Published: March 2021

Abstract
At present the manufacturing process throughout the hydraulic-hose assembly industry consists of manual operations. A study was conducted to determine the technical feasibility and costs of automating such a manufacturing plant.
This paper describes the two automation concepts that were developed. One employs a robot to transfer hoses between workstations, and the other employs a rotary indexing table. Both concepts employ common linear-positioning fixtures controlled by a programmable logic controller to provide necessary hose manipulations at each workstation. A design for a hose-gripper assembly to contain each hose throughout the manufacturing process was developed, as well as schemes for changing the design of current production machinery to meet automation requirements. Production rate and cost estimates of each automation concept are presented.
A Machine Vision System for Inspecting Hydraulic Hose Assemblies
Authors: Mehta Sudhir I. , Chenoweth Bruce B. 
Published: March 2021

Abstract
This paper describes a machine vision system for inspecting hydraulic hose assemblies. At present the inspection in this industry is done manually and is prone to human error. A specially designed hose gripping mechanism, a mandrel system, and a camera and lighting fixture allows the system to be integrated on a shop floor and is able to inspect various parameters of a fitting. The system allows the inspection to be done more accurately and improves the quality control process.
A Graph Based Heuristic Approach to Automated Assembly Planning
Authors: Yan Xue , Gu P. 
Published: March 2021

Abstract
Automatic generation of product assembly sequence is essential for robotic assembly task planning. In this paper, a graph-based heuristic approach is presented for assembly sequence planning. A product is represented in feature-based product model. A liaison graph is then formed based on assembly relations among components. The liaison graph is split into two or more pieces by removing the cutvertex from the graph. The pieces may also be split again until basic graph(bi-connected graph) are found. The basic graphs are considered as sub-assemblies. The disassembly sequence for each sub-assembly is determined. The disassembly sequences are then merged to generate a complete disassembly sequence for the product. Finally, the assembly sequence is defined by reversing the complete disassembly sequence.
Towards a Formal Model of Version and Configuration Management for Collaborative Engineering
Authors: Krishnamurthy Karthik , Law Kincho H. 
Published: March 2021

Abstract
This paper presents a formal model for the management of data for collaborative design that supports the requirements in each design discipline and provides a framework to integrate the individual designs to describe the overall project. A version model is proposed to manage design data in a given discipline, where a version specifies the state of a particular design in that discipline. The versioning scheme is hierarchical in structure and supports the independent evolution of multiple alternatives. In addition, this model proposes configurations as a mechanism to integrate designs from individual discipline. A configuration is defined as a set of component versions (one from each participating discipline) and an associated set of constraints. Finally, this paper discusses a model of versions to support configurations, and enumerates the preconditions on the operators related to version and configuration management.
Mechanical System Information Management in a Shared Multidisciplinary Environment
Authors: Wu J. K. , Yang X. , Li X. , Kvidera D. A. 
Published: March 2021

Abstract
This paper describes the information model and data management methods developed for the global database of a Concurrent Engineering environment for mechanical system design and evaluation. The environment considered has a CAD system and four CAE applications. The information model supports these engineering disciplines through multiple, unrestricted product composition hierarchies and a shared product definition. The dependency between the shared product definition and application models and between attributes of the parameterized, shared product definition are analyzed. The data management method employs a versioning policy that maintains consistent representations and history of the design as it undergoes design change transactions.