bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Pole Curve Generated by Infinite Poles
Authors: Brady Michael H. , Peterson Steven W. 
Published: March 2021

Abstract
In this paper, a general expression for the pole curve equation was derived in the projective plane is applied to opposite-pole quadrilaterals that contain one or more infinite poles. Such infinite poles arise in four-position synthesis when a lamina moves from one position to another in pure translation. Classical derivations of the pole curve equation are not valid when a pole is infinite because these derivations depend upon distances between poles. However, this projective approach relies only upon the homogeneous coordinates of the poles. As infinite poles have finite coordinates in the projective plane, this derivation readily accommodates infinite poles.
Burmester-Theory for Band-Mechanisms
Authors: Luck Kurt , Modler Karl-Heinz 
Published: March 2021

Abstract
A band-mechanism includes inter alia a flexible band and a disk-profile. Such a mechanism can excellent be used for path-generation, better than a four-bar-linkage. Also several plane-positions additionally can be realized. This paper investigates the synthesis of four-bar-band-mechanisms by using the complex vector-algebra. Several technical tasks demonstrate the flexible application of such mechanisms. This tasks are formulated analogous to the wellknown BURMESTER-THEORY, but with higher claims and the solution is done by analytical methods. Further it is demonstrated that a four-bar-linkage is a special case of a four-bar-band-mechanism.
Software for Optimum Gear Design (DISENG)
Authors: Jáuregui Juan Carlos , Sansalvador Rodrigo López , Aparicio Alfredo Ramos , Contreras Isaías Regalado 
Published: March 2021

Abstract
In this paper, a specialized software for optimum gear design is presented. This optimum is found through a logical solution search algorithm, rather than general optimization techniques. The logical search is based upon the constraints and needs set by the user, who defines the solution space and the search trajectory. For each problem, the solution will be the less expensive according to specific constraints. Calculation routines were based on AGMA standards, and input data routines were conceived to be as helpful as possible. A complete help routine is included on each part of the software and every input data is foolproof. It also includes a routine for intermediate results analysis that allows the user to verify every iteration.
Torque Resolver Design for Tendon-Driven Manipulators
Authors: Lee Jyh-Jone , Tsai Lung-Wen 
Published: March 2021

Abstract
Given a set of desired joint torques in an n-DOF tendon-driven manipulator with n + 1 control tendons, the determination of tendon forces is an indeterminate problem. Usually, the pseudo-inverse technique is used to solve for such a problem. In this paper, rather than using the pseudo-inverse technique, an efficient methodology for transforming joint torques (n elements) to motor torques (n + 1 elements) has been developed. This technique, called “torque resolver”, utilizes two circuit-like operators to transform torques between the two different vector spaces. It can be easily programmed on a digital computer or implemented into an analog-circuit system. It is hoped that this technique will make real-time computed-torque control feasible. The technique has been demonstrated through the dynamic simulation of a three-DOF manipulator.
Position-Force Synthesis of Closed-Loop Linkages
Authors: Huang Chintien , Roth Bernard 
Published: March 2021

Abstract
The dimensional synthesis of spatial closed-loop linkages to match both force and position specifications is investigated. An efficient means of formulating force equations is introduced through the application of linear algebra to screw theory. The synthesis of spatial four-bar linkages is discussed in detail; it is shown that the maximum number of allowable design positions is not decreased after force constraints are imposed on classical position synthesis problems.
Directional Probabilistic Design of Three-Coupler-Point Four-Bar Mechanisms
Authors: Schade George R. , Korbel Douglas R. , Shanmugam Deena D. 
Published: March 2021

Abstract
A standard four-bar coupler-point position synthesis technique is augmented with a probabilistic model of randomness coupler-point position caused by production variations in link dimension. The synthesis is optimized to reduce the variations in a chosen direction. The probabilistic optimum is verified by Monte-Carlo test.
Computer Aided Design and Analysis of the Rack and Pinion Mechanism
Authors: Srinivas D. , Kramer Steven N. 
Published: March 2021

Abstract
The general procedure for synthesizing the rack and pinion mechanism for six precision conditions is developed. To illustrate the method, the mechanism has been synthesized in closed form for generating both four prescribed path points with input coordination and two positions of function generation. This is the extension of the work reported earlier on this mechanism where only three path precision points were satisfied. The rack and pinion mechanism has a number of advantages over the conventional four bar linkage mechanism. First, since the rack is always tangent to the pinion, the transmission angle has a constant optimum value of 90 degrees minus the pressure angle of the pinion. Second, because both translation and rotation of the rack are possible, multiple outputs are available. Generation of monotonic functions for a wide variety of motion, and nonmonotonic functions for the full range of motion as well as nonlinear motions, are other advantages of this mechanism. The rack and pinion mechanism has applications in the packaging industry, in toys, and automotive steering mechanisms. In this work, the mechanism is made to satisfy a number of practical design constraints such as a completely rotatable input crank and others. Also, structural errors for function generation are calculated to give an estimate of the accuracy of the mechanism. The method of solution developed in this work uses the complex number method of mechanism synthesis and a FORTRAN program is written to find the solutions for any input.
Complete Solutions to Synthesis of Six-Link, Slider-Crank and Four-Link Mechanisms for Function, Path and Motion Generation Using Homotopy With M-Homogenization
Authors: Dhingra Anoop K. , Cheng Jyun-Cheng , Kohli Dilip 
Published: March 2021

Abstract
This paper presents complete solutions to the function, motion and path generation problems of Watt’s and Stephenson six-link, slider-crank and four-link mechanisms using homotopy methods with m-homogenization. It is shown that using the matrix method for synthesis, applying m-homogeneous group theory, and by defining compatibility equations in addition to the synthesis equations, the number of homotopy paths to be tracked can be drastically reduced. For Watt’s six-link function generators with 6 thru 11 precision positions, the number of homotopy paths to be tracked in obtaining all possible solutions range from 640 to 55,050,240. For Stephenson-II and -III mechanisms these numbers vary from 640 to 412,876,800. For 6, 7 and 8 point slider-crank path generation problems, the number of paths to be tracked are 320, 3840 and 17,920, respectively, whereas for four-link path generators with 6 thru 8 positions these numbers range from 640 to 71,680. It is also shown that for body guidance problems of slider-crank and four-link mechanisms, the number of homotopy paths to be tracked is exactly same as the maximum number of possible solutions given by the Burmester-Ball theories. Numerical results of synthesis of slider-crank path generators for 8 precision positions and six-link Watt and Stephenson-III function generators for 9 prescribed positions are also presented.
An Application of Generalized Kinematic Chains to the Structural Synthesis of Nonfractionated Epicyclic Gear Trains
Authors: Hsu Cheng-Ho 
Published: March 2021

Abstract
This paper presents a systematic approach, which is based on the concept of generalization for the structural synthesis of geared kinematic chains for epicyclic gear trains with any number of degrees of freedom. First, the fundamental rules of generalized kinematic chains for nonfractionated epicyclic gear trains are investigated. Next, according to the numbers of gear pairs and degrees of freedom, acceptable kinematic chains for nonfractionated epicyclic gear trains are identified from an atlas of basic kinematic chains. Then, each acceptable kinematic chain is specialized to be epicyclic gear trains. Finally, geared kinematic chains for nonfractionated epicyclic gear trains with up to three degrees of freedom and four gear pairs have been susscessfully constructed.
A Proposed Method to Group the Solutions From Dimensional Synthesis: Planar Triads for Six Precision Position
Authors: Lu Xiancheng , Lin Chuen-Sen 
Published: March 2021

Abstract
In this paper, a method has been proposed to group into six sets the infinite number of solutions from dimensional synthesis of planar triads for six precision positions. The proposed method reveals the relationships between the different configurations of the compatibility linkage and the sets of numerical solutions from dimensional synthesis. By checking the determinant signs and the contunities of values of the sub-Jacobian matrices and their derivatives with respect to the independent angular displacement for all constraint sets in the compatibility linkage, it enables the computer to identify and group the synthesized solutions.
Numerical examples have been given to verify the applicability of this method. Six sets of the partial triad Burmester curves have been plotted based on grouped solutions. Suitable solutions can be easily found from the partial triad Burmester curves and utilized for the prescribed design task. This method provides a useful tool to group the dimensional synthesis solutions and enhances the computer automation in the design of linkage mechanisms.
Four-Position Synthesis for Spatial Mechanisms With Two Independent Loops
Authors: Chiang Chien H. , Chieng Wei Hua , Hoeltzel David A. 
Published: March 2021

Abstract
Mathematical models that have been employed to synthesize spatial mechanisms for rigid body guidance have been found to be too complicated to implement in practical applications, especially for four-position guidance synthesis. This paper describes simple analytical methods for synthesizing single degree-of-freedom spatial mechanisms having two independent loops for four precision positions. In addition, prescribed timing has been simultaneously considered for several spatial mechanisms.
Tool Path Geometry for Multi-Axis Kinematics Conversion in CAD-CAM Integration
Authors: Chou Jui-Jen , Yang D. C. H. 
Published: March 2021

Abstract
In the integration of CAD and CAM, it is necessary to relate machine tool kinematics and control in a CAM process to the geometrical data in a CAD model. The data stored in a CAD model is usually static in nature and represented by unitless parameters. Yet, in machine tool motion and control, the data should be transformed into a time dependent domain. In this paper, a general theory on the conversion from desired paths to motion trajectory is analytically derived. The geometrical properties of a desired path, including position, tangent, and curvature are related to the kinematics of coordinated motion including feedrate, acceleration, and jerk. As a result, the motion commands used as control references to track arbitrary space curves for five-axis computer-controlled machines can be generated in a rather straight-forward as well as systematic way.
Automatic Generation of Piecewise Constant Speed Motion for Multi-Axis Machines
Authors: Yang D. C. H. , Chou Jui-Jen 
Published: March 2021

Abstract
This paper presents a general theory on the generation of smooth motion profiles for the coordinated motion of multi-axis manipulators with orthogonal regional structures. Motion with constant speed is important and required in many manufacturing processes, such as milling, welding, finishing and painting. In this paper, a piecewise constant speed profile is constructed by a sequence of Hermite cuves to form a composite Hermite curve in parametric domain. Due to the continuity of acceleration in the proposed speed profile, it generates relatively better product quality than traditional techniques. Besides, we also provide a method for the feasibility study of manufacture capability in terms of the given manipulator, the desired path, and the assigned speed. This includes the consideration of manipulator dynamics, actuator limitation, path geometry, jerk constraints and motion kinematics. The result is a general one and is applicable to all curves tracked by multi-axis manipulators with orthogonal regional structures.
A Quintic Spline Interpolator for Motion Command Generation of Computer-Controlled Machines
Authors: Yang D. C. H. , Wang Fu-Chung 
Published: March 2021

Abstract
This paper presents a new method of motion command generation for computer controlled multi-axis machines. The method is based on a quintic spline interpolator (QSI) which generates motion commands to trace a set of desired discrete position data via a composite quintic spline (CQS). This CQS is nearly arc length parametrized and has both tangents and curvatures continuous at the data points. Consequently, the generated motion trajectories are continuous in both velocity and acceleration throughout the motion. A quick motion command generation scheme is also developed. Compared to the existing linear interpolator (LI), the proposed method takes comparable execution time, but is superior in many other aspects, including position accuracy, speed smoothness, acceleration continuity, torque requirement and jerk reduction. Compared to the existing cubic spline interpolator (CSI), the proposed method is able to maintain a similarly smooth composite profile, but better speed accuracy. On-line implementation of this interpolator is believed very promising.
Optimization of Mechanism Timing Using Noncircular Gearing
Authors: Bernard Judd 
Published: March 2021

Abstract
A single degree of freedom mechanism whose input link is a crank driven through continuous revolutions will generate output motions dependent upon the inherent mechanism geometry. For example, the slider of a slider-crank mechanism has a linear displacement (the output motion) as a function of the crank rotation (input). Only within the realm of link proportioning can the slider crank output-input function be altered.
In this investigation, the continuously rotating crank of a mechanism is rigidly attached to a gear which is one of a pair of externally meshing noncircular gears. By using noncircular gears, it will be shown that the output motion of the given mechanism can be correlated to the rotation of the mating gear to which the crank is not attached. In this fashion, the output link can then be made to execute its motion according to any prescribed law. The above technique has been implemented for the cases of a crank and rocker mechanism and a slider-crank mechanism.
Synthesis of an RSSR-SS Mechanism Using a Continuation Method
Authors: Subbian Thiagaraj , Flugrad Donald R. 
Published: March 2021

Abstract
Precision position synthesis of an RSSR-SS mechanism is considered. The RSSR-SS mechanism is broken up into two RS and one SS dyads. These components are designed independently using a continuation method. This treatment is possible for a maximum of four precision positions.
A parameter homotopy is implemented for the RS dyads and a 3-homogeneous traditional homotopy is used for the SS dyad design. Two example problems are considered.
Position and Force Control of Multibody Systems by Feedback Linearization
Authors: Woernle Christoph 
Published: March 2021

Abstract
A unified formulation of the feedback linearization method to the hybrid position and force control of constrained multibody systems is developed. Similar to the feedback linearization of unconstrained systems, linear decoupled input-output channels for position and force control variables, which can be controlled separately, and a nonlinear nonobservable internal dynamics are obtained. Technical applications are robotic systems with multiple, interacting arms, multifingered grippers grasping an object, mechanisms with controlled motion, or walking machines.
Formulating Dynamic Equations of Elastic Multibody System via the Method of Typical Substructures
Authors: Hongzhao Liu , Cao Wei-qing 
Published: March 2021

Abstract
In this paper, a method of using multibodies as substructures to establish the dynamic equations of elastic multibody systems involving closed loops is put forward. Plane elastic linkage is divided into four typical substructures, and equations of free two-link dyad — the most general one among the four substructures — are derived. Also some examples of substuctures’ partitioning of mechanisms are given to show the present method’s advantages. By means of the present method, the number of system’s constraint equations can be greatly reduced, and it will facilitate solving dynamic equations on a microcomputer.
The Effects of the Manipulator Type on the Vibrational Excitation During Motion
Authors: Tu Q. , Rastegar Jahangir 
Published: March 2021

Abstract
The relationship between the structural type of a manipulator and its susceptibility to motion induced vibrational excitation is examined. For manipulators of different type, the average potential resonant energy transfer to a robot manipulator system by the higher harmonics of the actuating torques (forces) necessary for tracking trajectories that are uniformly distributed within a representative task space are determined, and used as a measure of the potential for vibrational excitation during motion. The manipulators are kinematically and dynamically equivalent. From the vibration and control points of view, manipulator types that do not demand high frequency actuating torque harmonics are more desirable, since the natural modes of vibration of mechanical systems are most likely to be excited by the higher harmonics of the actuating torques, and because of practical dynamic response limitations of all mechanical systems. As examples, plane two and three degrees-of-freedom manipulators constructed with revolute and prismatic joints are studied. Numerical calculations of the aforementioned and the total expected (average) energy input and the corresponding variances are presented for the two degrees-of-freedom manipulators. A number of points of interest are discussed.
Computer-Based Kinematical Analysis of Spatial Multiloop Mechanisms
Authors: Hiller Manfred , Möller Manfred 
Published: March 2021

Abstract
In this paper a method for the automatical analysis of the kinematics of spatial multiloop mechanisms is presented. The mechanism is regarded as a multibody system. Connecting joints are revolute joints (R), prismatic joints (P), spherical joints (S) and all further joints that can be modelled as combinations of these joints. The concept allows the application for a user without deeper theoretical knowledge of spatial kinematics. Special effort has been taken in the reduction of the number of nonlinear constraint equations that must be solved. This is done by using an approach, yielding a suitable structure of the system of nonlinear constraint equations, where only those with interesting unknown joint coordinates must be solved. An optimized solution of these equations allows in many cases a partly and sometimes even a completely explicit solution of the constraint equations. The described method is also applicable to overconstrained spatial mechanisms.
Assemblability, Circuits, Branches, Locking Positions and Rotatability of Input Link of Mechanisms With Four Closures
Authors: Kohli Dilip , Cheng Jyun-Cheng , Tsai K. Y. 
Published: March 2021

Abstract
A general analytical treatment is provided for determining the conditions for the assemblability, rotatability of input link, locking positions and the number of circuits of mechanisms with four closures and a quartic input-output displacement polynomial. It is shown that the assemblability, rotatability of input crank and the locking positions are branch dependent properties for the mechanisms with four closures and such mechanisms, in genera], can have many branch dependent circuits. Such mechanisms may be assemblable for only two branches instead of all four. It is shown that the input link rotatability is not only branch dependent but also depends on the starting position and the direction of motion of the input link. The input link may be continuously rotatable for one branch while for the other branch it may go through one cycle of rotation (&gt; 2π but less than 4π) and then experience a locking position.
Examples dealing with assemblability, branching, locking positions, and rotatability of the input link is presented for the spatial five-link RRRSR, RPRSR, RRPSR, and RRRSR mechanisms are presented.
Study on the Spatial Linkage With the Property of Constant Pressure Angle
Authors: Wenjun Zhang , Breteler A. J. Klein 
Published: March 2021

Abstract
This paper for the first time detects a new kind of spatial linkage which has the property of constant pressure angle (termed as CPA), that is, the pressure angle of linkage keeps a constant value during the gross motion of the input. The existence and the method to detect out this kind of spatial linkage have been discussed. Two cases with the property of CPA have been found for the spatial linkage RSSR.
Motion Representation: Different Conventional Forms, Duplex Mapping and Conjugation Form
Authors: Chen Chih-Hsin , Chen Hong-Jian 
Published: March 2021

Abstract
Four fundamental forms for representing rigid body motion, i.e. the rotation-of-vector form, the matrix form, the quaternion form and the screw form, all based on the conventional concept that motion is specified by the movement of a reference point together with an orientation change, are expounded. The inter-relationships among these forms are elucidated. The geometric images of these representation-forms, i.e. the motion mappings, are explained, and an innovative duplex-mapping, a powerful tool for mobility analysis of multi-loop mechanisms and robots, is introduced. An exotic motion representation, based on a concept totally different from the conventional concept, is described. This is a purely geometric representation, a representation by a pair of conjugate curves on respective conjugate surfaces, and is called the conjugation form of motion representation. The conversion from the conjugation form to the rotation-of-vector form and the inverse conversion are described. These conversions, which constitute the essential and featured contents of the Theory of Conjugate Surfaces, have great potential applications in motion design for numerically controlled manufacturing and in surface generation by numerically controlled manufacturing. The basis equations for the conversions, i.e. the three relationship-equations, are deduced. The fundamental equation conjugation, the four conjugato-kinematic entities and the five differential formulas for the inverse conversion are derived.