bluuebunny/crossref_metadata_2025_split huggingface dataset:
Pitting Resistance and Bending Strength of Bevel and Hypoid Gear Teeth
Authors: Höhn B.-R. , Winter H. , Michaelis K. , Vollhüter F. 
Published: March 2021

Abstract
Bevel and hypoid gears are widely used for gears with crossed axis. The influence of a pinion offset on the load carrying capacity — pitting resistance and bending strength — is introduced in a different way in commonly used calculation methods. Load carrying and measurement investigations on the influence of pinion offset on pitting resistance and bending strength are reported. Tests show an increasing bending strength and decreasing maximum tooth root stresses with increasing pinion offset. Also a slight increase of pitting resistance and a slight decrease of the Hertzian pressure was evaluated. The load carrying calculation results for bevel gears without pinion offset, DIN 3991, is in good agreement with test results. The bending strength of hypoid gears calculated according to Niemann/Winter, is greater than that experimentally measured. For pitting resistance, however, the calculation is less than the measured results.
Dynamics of a Truck Gearbox
Authors: Perret-Liaudet J. , Sabot J. 
Published: March 2021

Abstract
This work is concerned with numerous numerical simulations of the overall dynamic behaviour of a parallel helical gear transmission. These results are compared to vibratory measurements made with a simplified gearbox test rig.
The dynamic modeling of the elastic components of the gear transmission (gears, shafts, bearings, housing) is realized using the finite element method. Fluctuated gear mesh stiffness is introduced owing to stiffness matrix which describes the elastic coupling between the pinion and the wheel. The kinematic transmission error is introduced as a vibratory excitation source. The equations of motion are established in a truncated modal base deduced from the average characteristics of the structure. A new computing method, called “Spectral Method”, is used for analytical study of a simplified gearbox whose housing is a simple rectangular plate.
The numerical results allows us to conclude on the dominent phenomenon of the overall dynamic behaviour of the gear transmission. They exhibit in particular the main characteristics of the transfer between the static transmission error and the vibratory response of the gearbox.
A series of vibration measurements made on a gearbox close to that used for the numerical simulations, has confirmed this characteristics.
Dynamics of a Split Torque Helicopter Transmission
Authors: Rashidi Majid , Krantz Timothy L. 
Published: March 2021

Abstract
A high reduction ratio split torque gear train has been proposed as an alternative to a planetary configuration for the final stage of a helicopter transmission. A split torque design allows a high ratio of power-to-weight for the transmission. The design studied in this work includes a pivoting beam that acts to balance thrust loads produced by the helical gear meshes in each of two parallel power paths. When the thrust loads are balanced, the torque is split evenly. A mathematical model was developed to study the dynamics of the system. The effects of time varying gear mesh stiffness, static transmission errors, and flexible bearing supports are included in the model. The model was demonstrated with a test case. Results show that although the gearbox has a symmetric configuration, the simulated dynamic behavior of the first and second compound gears are not the same. Also, results show that shaft location and mesh stiffness tuning are significant design parameters that influence the motions of the system.
The Optimum Modification of Tooth Profile for a Pair of Spur Gears to Make its Rotational Vibration Equal Zero
Authors: Cai Yurong , Hayashi Teru 
Published: March 2021

Abstract
This paper develops an optimum modification method of tooth profile for a pair of spur gears to make its rotational vibration become zero by using an exact vibration model. By minimizing the equivalent exciting force, which includes the effects of the static load, time-varying stiffness, and relative tooth profile error, each optimum modification curve for each gear pair with different designed contact ratios can be obtained. The magnitude and the shape of the optimum modification curve depend upon the value of the designed contact ratio ε strongly. Especially, the concave modification curve is obtained in case of ε ≤ 1.1. The effect of the optimum modification on eliminating the vibration, is verified by the numerical calculation using an exact equation of vibration. A parameter study is presented to investigate the effect of running condition.
Computational Issues Associated With Gear Rattle Analysis: Part II — Evaluation Criteria for Numerical Algorithms
Authors: Barlow R. C. , Padmanabhan C. , Singh Rajendra 
Published: March 2021

Abstract
The main focus of this study is to establish evaluation criteria for direct time domain integration algorithms used to solve gear rattle type problems. Such criteria may be used to identify specific numerical problems encountered. The ultimate goal obviously is to find reasonably accurate and reliable methods of solution for such physical systems. Six case studies of increasing complexity, linear to highly non-linear, are solved using well known algorithms. The solutions to the linear model are verified by using analytical results. Non-linear model solutions as yielded by different algorithms are compared qualitatively and quantitatively. Several non-linear simulation models have been validated by comparing predictions with experimental data and results available in the literature.
Design and Construction of a Machine to Evaluate the Forces in Roller Chain Drives
Authors: Conwell James C. , Johnson Glen E. , Peterson S. W. 
Published: March 2021

Abstract
In this article, a brief history of chain drives is presented, and the design and construction of a machine to investigate chain drive force phenomena is discussed. The new test machine allows the measurement of the impact force between a roller and the sprocket during “seating” and it can also be used to measure the forces that exist in the link sides plates during normal operation (including start-up and shut down conditions). Data can be obtained for a wide range of chain loads and speeds. Two companion papers (“Experimental Investigation of the Impact Force that Occurs When a Roller Seats on the Sprocket During Normal Operation of a Roller Chain Drive” and “Experimental Investigation of the Forces in a Link Side Plate During Normal Operation of a Roller Chain Drive”, both presented at this conference) describe experiments that have been completed with this test machine.
Experimental Investigation of the Forces in a Link Side Plate During Normal Operation of a Roller Chain Drive
Authors: Conwell James C. , Johnson Glen E. , Peterson S. W. 
Published: March 2021

Abstract
The fluctuation in the tension of a chain link during normal operation is very likely the root cause of chain stretch and fatigue in roller chain drives. In this paper we present the results from a recent experimental investigation of this tension variation phenomenon. The experimental procedure is described, and data are presented for a wide range of initial tensions, transmitted loads, and chain speeds.
At low speeds, the data give reasonable agreement with previously published theoretical models for quasi-static load distribution. However, at higher speeds (where inertia effects are more significant) the experimental results indicate that quasi-static models do not provide an adequate explanation. The differences are noted and discussed. An empirical equation for “tight side” chain tension is presented in terms of torque transmitted, sprocket pitch radius, mass per unit length of chain, and linear chain speed. This paper is accompanied by companion papers that describe the design and construction of the test machine and the measurement of the impact force as a roller seats on the sprocket.
Synthesis and Experimental Validation of Dynamic Parts-Orienting Devices
Authors: Han Inhwan , Gilmore B. J. , Ogot M. M. 
Published: March 2021

Abstract
Part orientation is an important aspect of factory automation. The parts-orienters presented by this paper are flexible to handle a variety of parts, passive (cost effective) and high-speed (i.e., include significant inertial effects). This paper presents a dynamic synthesis approach of gravity fed parts-orienters. In general, previous works were constrained by their quasi-static analyses. This research demonstrates the synthesis for dynamic parts-orienters based on the mechanics of the system using a simulation package as a design tool. The dynamic effects considered by this work include friction, inertial forces, impact with friction and contact/no-contact (changing kinematic constraints). The passive part orientation systems, which are developed by dynamic system synthesis in the presence of friction and impact, succeed in aligning a part into a specified orientation and through experiment are shown to be valid. This paper presents and experimentally validates a synthesis approach for dynamic mechanical systems with changing kinematic constraints. The experimental validation uses high speed video.
A Blackboard Architecture to Support Case-Based Reasoning in Mechanical Design
Authors: Bardsz Theodore , Zeid Ibrahim 
Published: March 2021

Abstract
One of the most significant issues in applying case-based reasoning (CBR) to mechanical design is to integrate previously unrelated design plans towards the solution of a new design problem. The total design solution (the design plan structure) can be composed of both retrieved and dynamically generated design plans. The retrieved design plans must be mapped to fit the new design context, and the entire design plan structure must be evaluated. An architecture utilizing opportunistic problem solving in a blackboard environment is used to map and evaluate the design plan structure effectively and successfuly. The architecture has several assets when integrated into a CBR environment. First, the maximum amount of information related to the design is generated before any of the mapping problems are addressed. Second, mapping is preformed as just another action toward the evaluation of the design plan. Lastly, the architecture supports the inclusion of memory elements from the knowledge base in the design plan structure. The architecture is implemented using the GBB system. The architecture is part of a newly developed CBR System called DEJAVU. The paper describes DEJAVU and the architecture. An example is also included to illustrate the use of DEJAVU to solve engineering design problems.
Representing Geometric Viariations in Complex Structural Assemblies on CAD Systems
Authors: Shalon Dari , Gossard David , Ulrich Karl , Fitzpatrick David 
Published: March 2021

Abstract
In previous airplane programs, Boeing identified interferences and misalignments between airplane parts as the two largest causes of engineering changes. Boeing is currently designing the 777 with a state-of-the-art solid modeling system. While the system is capable of detecting interferences and misalignments between ideally-sized and ideally-located solid models, it cannot model the effects of variation in the size, shape and location of parts and tools. This paper presents an initial, novel framework for modeling these variations called Indexed Pre-Assembly with Variation (IPAV).
The main points made in this paper are:
• Variations in both parts and tools should be modeled in exactly the same way.
• Mating features of parts and tools can be represented in the solid models with local index-point coordinate systems.
• Linking the mating index-point coordinate systems enables the positioning of the solid models in an assembly.
• The order in which the index-point coordinate systems are linked corresponds to the planned assembly sequence.
• The effects of size, shape and location variations on an assembly can be modeled by manipulating the index-point coordinate systems within the individual solid models.
The academic literature on tolerancing and existing software tools for tolerance analysis are reviewed. A survey of Boeing engineers is presented which led to the development of the Indexed Pre-Assembly with Variation method. A case study involving an actual assembly problem at Boeing is analyzed with IPAV. The paper also discusses the benefits of simulating variation at the design stage and proposes an implementation plan to integrate IPAV into a generic airplane development schedule. Lastly, the applicability of IPAV to other industries is evaluated and areas for further research are identified.
A Single-DOF Multi-Function Prosthetic Hand Mechanism With an Automatically Variable Speed Transmission
Authors: Guo Gongliang , Qian Xikang , Gruver Willim A. 
Published: March 2021

Abstract
This research concerns the design of a new three-fingered anthropomorphic hand mechanism for prosthetic and robotic applications. Based on the configuration and flexion/extension features of human hands, we develop a three-jointed finger mechanism using a gear-constrained planar five-bar linkage with a single degree of freedom (DOF). From an operational study of human hands, we also propose a multi-functional palm mechanism using a cam-groove submechanism. The hand can perform grasping, holding and pinching operations. To achieve the automatic shape adaptability of a human hand, a selfadaptable submechanism was designed within the palm based on the lever principle. An automatically variable speed transmission with selfadaptability was developed for this hand to achieve optimal flexing speed and optimal fingertip forces. This paper describes the mechanical structure and operational principles of this new prosthetic device.
On the Kinematics of the UPS Wrist for Real Time Control
Authors: Lee Jason J. , Chang Sun-Lai 
Published: March 2021

Abstract
A parallel structure is used in the design of the UPS wrist to allow for a large payload, high speed, high repeatability, and a large workspace. Because of the inherent design and machining difficulties involved with spherical mechanisms, a spatial mechanism has been adopted. In creating such a 3-DOF spatial mechanism, many practical design problems are unavoidable, and direct analysis of the mechanism becomes extremely difficult. In this paper, we discuss the concept of using an equivalent mechanism to simplify the kinematic analysis. By using this method, we have derived a closed-form solution for the inverse kinematics, as well as a formulation for the forward kinematics. We have also developed a numerical algorithm for the forward kinematics, and a methodology for implementing the results of the analysis. The results of this study have enabled real time control and force control to become feasible for the UPS wrist.
A Drift-Free Navigation System for a Mobile Robotic Vehicle Operating on Unstructured Terrain
Authors: Sreenivasan S. V. , Waldron Kenneth J. 
Published: March 2021

Abstract
The orientation and the angular rates of the body of a robotic vehicle are required for guidance and control of the vehicle. In the current robotic systems these quantities are obtained by the use of inertial sensing systems. Inertial sensing systems involve drift errors which can be significant even after the vehicle has traversed only short distances on the terrain. A different approach is suggested here which guarantees accurate, drift-free sensing of the angular position and rates of the vehicle body. A camera system consisting of two cameras in fixed relationship to one another is made to continuously track two stationary objects. The camera system is mounted on the vehicle body through an actuated three degree of freedom joint. The angular positions and rates of these joints can be used to evaluate the angular positions and rates of the vehicle body. An approximate estimate of the position of the vehicle on the terrain can also be obtained from the sensing system. This can serve as primary system for estimating the vehicle position, or as a backup to a more accurate scheme for obtaining the position of the vehicle on the terrain.
Grashof Type Rotatability Criteria of Spherical Five-Bar Linkages
Authors: Kohli Dilip , Khonji Ardie 
Published: March 2021

Abstract
In this paper rotatability criteria of spherical five bar linkages are analytically derived. First an equivalent linkage in which sum of any two link lengths is less than π is found and then rotatability criteria of spherical 5 bar linkage are developed for this linkage. The rotatability criteria developed in this paper are stated as follows:
The two input angles are completely revolvable if and only if in the equivalent linkage the sum of the longest and the two shortest links is less than the sum of the remaining two links and there is one and only one long link between each pair of noninput angles (long link being any link excluding the shortest links). It is also shown that an angle θ included by two links αi and αj is completely revolvable if and only if the sum of the longest link and shorter of αj and αj is less than or equal to the sum of the remaining three links.
Development of Commercial Quality Software for Mechanisms Design Education
Authors: Timmins Steven J. 
Published: March 2021

Abstract
Development of high quality technical software in a university environment has been a persistent problem since the introduction of educational software to institutions of higher learning. Design software presents a number of special considerations. It differs significantly from other types of educational software in that it requires a free-form creative environment rather than a question-and-answer format or even a detailed analysis of a fixed set of specified problems. Ideally, the student should be able to explore a wide range of realistic problems and develop both optimal and non-optimal solutions using a variety of mechanisms. This paper outlines the differences between truly “commercial quality” software and that developed for use at the local campus and explores the difficulties involved in producing such a product.
Users drastically underestimate the amount of manpower and funding required to develop software packages on a par with widely available applications such as AutoCAD, WordPerfect, or Lotus 1-2-3. Similarly, design education software developed at universities for national distribution represent thousands of man-hours of development and may be the work of a single individual or a team of programmers led by a faculty member.
On Flexible Pin Shafts and Clearance Interaction for the Dynamic Response of Planar Mechanisms
Authors: DeRong Wu 
Published: March 2021

Abstract
The dynamic equations of planar mechanisms with flexible pin shafts and clearance connections is developed here using Lagrangian formulation. The general flexible-connection planar mechanism can be described by a damped, circulatory, gyroscopic system. Quite often, damping and circulatory forces are small, one may regards them as the perturbations. Indeed, a perturbation method for obtaining the eigensolution and dynamic response is presented by regarding the undamped, non-circulatory, gyroscopic system as the unperturbed system.
The procedure may be used to investigate the fundamental nature of dynamic interaction between the elastic deflection of pin shafts and clearance connections. A major objective of this paper, in addition to the development of the analytical technique, was to obtain some insight into the phenomenon at flexible-connection, so that these effects may be included during the designing of mechanisms.
Object Norms: A Class of Coordinate and Metric Independent Norms for Displacements
Authors: Kazerounian Kazem , Rastegar Jahangir 
Published: March 2021

Abstract
Defining a “norm” that quantifies a measure of “distance” for rigid body displacement in plane or space, is essential to many problems in kinematics, dynamics and control of mechanical and manufacturing systems. The norm is an abstraction of our usual concept of the length. The mapping between different generalized coordinate systems used in the analysis or control of systems may also be derived from this norm. All such norms currently used in different analysis are highly sensitive to 1) coordinate systems defined, and 2) metrics defined.
A new class of norms is proposed to quantify the distance in the space. These norms are independent of the coordinate systems or metrics used. Its applications indesign, precision manipulation and control, computational kinematics and dynamics, assembly and part mating in manufacturing, space kinematics and dynamics, shape optimization and motion planning are explored.
Torsional and Translational Vibrations of a Drive Shaft System With a Cardan Joint
Authors: Routson Richard L. , Starkey John M. , Wang Peishuh , Davies Patricia 
Published: March 2021

Abstract
A drive-shaft system was designed and built for studying the effects of a Cardan joint on torsional and translational shaft vibrations. The design of the system is described, and the results of a modal test are included. The system was also used to test the validity of a new optical torsional vibrometer. Measurements on the system indicate that (1) clearances significantly effect the torsional resonances, (2) second order responses due to the parametric variations in the Cardan joint dominate the response, and (3) the optical probe system shows promise as a non-contacting torsional and translational vibrometer.
A Model of the Human Spine: Forward and Inverse Kinematics
Authors: Agrawal Sunil Kumar , Li Siyan , Desmier Glen 
Published: March 2021

Abstract
The human spine is a sophisticated mechanism consisting of 24 vertebrae which are arranged in a series-chain between the pelvis and the skull. By careful articulation of these vertebrae, a human being achieves fine motion of the skull. The spine can be modeled as a series-chain with 24 rigid links, the vertebrae, where each vertebra has three degrees-of-freedom relative to an adjacent vertebra. From the studies in the literature, the vertebral geometry and the range of motion between adjacent vertebrae are well-known. The objectives of this paper are to present a kinematic model of the spine using the available data in the literature and an algorithm to compute the inter vertebral joint angles given the position and orientation of the skull. This algorithm is based on the observation that the backbone can be described analytically by a space curve which is used to find the joint solutions..
Measurement and Theoretical Analysis of Elastic Locus of High-Speed Mechanism
Authors: Zou Hui-jun , Wang L. , Kovacevic R. 
Published: March 2021

Abstract
With increase of machine speed, the influence of elastic components on dynamic characterises has become a very challenging problem. In our paper, we use self-made fiber-optic sensor on-line to detect the elastic locus. The sensor has highly transmitting and collecting light properties so that steady elastic locus has high precision and distinguishabilty. A theoretical analysis has been conducted using our program KEDL. The conclusions reveal more information about the dynamic characteristics of high-speed mechanisms.
The Virtual Manufacturing Workstation
Authors: Mills J. J. , Huff B. , Criswell T. , Graham J. 
Published: March 2021

Abstract
The Virtual Manufacturing Workbench is a project to develop an integrated set of tools with which a team of engineers can design, program, test and debug complex manufacturing systems. The approach taken includes developing a manufacturing system with individual tools, developing general requirements for an integrated system, defining an architecture that meets those requirements, and developing a prototype to test the architecture and test and refine the requirements. Some of the requirements for such a system are discussed as well as the status of the two prototypes presented.