bluuebunny/crossref_metadata_2025_split huggingface dataset:
Mechatronics at Rensselaer: Integration Through Design
Authors: Craig Kevin 
Published: March 2021

Abstract
Mechatronics is the synergistic combination of precision mechanical engineering, electronics, control engineering, and computer science in the design process. This paper describes a new elective course entitled Mechatronics which has been developed and was taught for the first time at Rensselaer during the fall 1991 semester to 45 senior-undergraduate and graduate students. The key areas of mechatronics which are studied in depth in this course are: control sensors and actuators, interfacing sensors and actuators to a microcomputer, discrete controller design, and real-time programming for control using the C programming language. The course is heavily laboratory-based with a two-hour laboratory weekly in addition to three hours of classroom lecture. The laboratory exercises include computer-aided control system design using MATRIXx, various analog and digital sensors, hydraulic actuators, DC and stepper motors, and computer control of a variety of physical systems. The unifying theme for the course is the integration of these key areas into a successful mechatronic design. Students are required, as a final project, to: identify a problem or need, analyze the problem, and write a problem statement; perform a state-of-the-art review; develop a list of specifications and identify the key specifications; generate an outstanding mechatronic-system conceptual design; and finally perform a detailed design of the system which may include model building and hardware development. Examples of student projects are described. This course should significantly enhance our design education program in the Mechanical Engineering Department and lay the foundation for the students to become mechatronic design engineers.
An Interactive, Menu-Driven, Software for Flexural Analysis of Transversely Loaded Beams
Authors: Pao Y. C. , Yur Winston 
Published: March 2021

Abstract
A set of computer programs written in QuickBASIC language has been developed as an instructional aid for the Mechanics of Materials course. It consists of 9 programs and over 50 supporting subprograms. Starting with the span and loading inputs, this software computes the support reactions and displays the diagrams of distributed loads, shearing force, bending moments, slope, and deflection distributions. Disk files are created to save the input and computed data and also the resulting displays for quick retrieval during any phase of the flexural analysis. Various shapes of cursors are created on screen for the user to select any menu involved in the analysis and/or a desired section of the beam for computation of the principal and maximum shearing stresses, for which Mohr’s circle display is also an optional feature. All operations are interactive and menu-driven, and provided with many helpful prompting messages to assist the user to specify the next request.
Development of an Interactive Teaching Tool: Course Designer
Authors: Kilkiş Birol , Kaftanoğlu Bilgin , Güngör Cengiz 
Published: March 2021

Abstract
An expert authoring package for real time, computer aided lecturing was developed with main emphasis to undergraduate courses in mechanical engineering. It enables the instructor to prepare the lecture and then present it in the classroom in a real-time and iterative environment. The major aim is to create a medium in which the instructor, computer and students are brought together on a common data base with real-time interaction with each other. The hardware necessary to enable such an interaction was investigated and optimum configuration laid out both from economical and technical points of view. The package is also flexible enough to permit the instructor to modify and set the topics during the course through a specially designed menu. The Course Designer program which was developed on SuperEdit™ software which enables to structure the course material to be structured using traditional Macintosh building blocks like windows and graphics with a better user friendly and interactive medium.
Computer Representation of the Machining Environment
Authors: Zhang J. , de Sam Lazaro A. , Kendall L. A. 
Published: March 2021

Abstract
Machining is an operation which utilizes both deterministic and heuristic inputs. Quantitative and qualitative judgments are made in order to optimize the process. Geometry, tool path control and so on are generally pre-defined whereas machining parameters such as cutting speed, feed rate and depth of cut require both mathematical and intuitive analyses to produce the best results. Computer representation of the machining environment requires both mathematical and heuristic models. A hybrid model for machining is presented and discussed. The model is simulated experimentally in an intelligent supervisory control system for CNC tape tuning.
Derivation of the Explicit Solution of the Inverse Involute Function and its Applications
Authors: Cheng Harry Hui 
Published: March 2021

Abstract
The involute function ε = tanϕ – ϕ or ε = invϕ, and the inverse involute function ϕ = inv−1(ε) arise in the tooth geometry calculations of involute gears, involute splines, and involute serrations. In this paper, the explicit series solutions of the inverse involute function are derived by perturbation techniques in the ranges of |ε| &lt; 1.8, 1.8 &lt; |ε| &lt; 5, and |ε| &gt; 5. These explicit solutions are compared with the exact solutions, and the expressions for estimated errors are also developed. Of particular interest in the applications are the simple expansion ϕ = inv−1(ε) = (3ε)1/3 – 2ε/5 which gives the angle ϕ (&lt; 45°) with error less than 1.0% in the range of ε &lt; 0.215, and the economized asymptotic series expansion ϕ = inv−1 (ε) = 1.440859ε1/3 – 0.3660584ε which gives ϕ with error less than 0.17% in the range of ε &lt; 0.215. The four, seven, and nine term series solutions of ϕ = inv−1 (ε) are shown to have error less than 0.0018%, 4.89 * 10−6%, and 2.01 * 10−7% in the range of ε &lt; 0.215, respectively. The computation of the series solution of the inverse involute function can be easily performed by using a pocket calculator, which should lead to its practical applications in the design and analysis of involute gears, splines, and serrations.
Kinematical Optimization of Spiral Bevel Gears
Authors: Fong Zhang-Hua , Tsay Chung-Biau 
Published: March 2021

Abstract
Kinematical optimization and sensitivity analysis of circular-cut spiral bevel gears are investigated in this paper. Based on the Gleason spiral bevel gear generator and EPG test machine, a mathematical model is proposed to simulate the tooth contact conditions of the spiral bevel gear set. All the machine settings and assembly data are simulated by simplified parameters. The tooth contact patterns and kinematic errors are obtained by the proposed mathematical model and the tooth contact analysis techniques. Loaded tooth contact patterns are obtained by the differential geometry and the Hertz contact formulas. Tooth surface sensitivity due to the variation of machine settings is studied. The corrective machine settings can be calculated by the sensitive matrix and the linear regression method. An optimization algorithm is also developed to minimize the kinematic errors and the discontinuity of tooth meshing. According to the proposed studies, an improved procedure for development of spiral bevel gears is suggested. The results of this paper can be applied to determine the sensitivity and precision requirements in manufacturing, and improve the running quality of the spiral bevel gears. Two examples are presented to demonstrate the applications of the optimization model.
Application of Face-Gear Drives in Helicopter Transmissions
Authors: Litvin F. L. , Wang J.-C. , Bossler R. B. , Chen Y.-J. D. , Heath G. , Lewicki David G. 
Published: March 2021

Abstract
The use of face gears in helicopter transmissions was explored. A light-weight, split torque transmission design utilizing face gears was described. Face-gear design and geometry were investigated. Topics included tooth generation, limiting inner and outer radii, tooth contact analysis, contact ratio, gear eccentricity, and structural stiffness. Design charts were developed to determine minimum and maximum face-gear inner and outer radii. Analytical study of transmission error showed face-gear drives were relatively insensitive to gear misalignment, but tooth contact was affected by misalignment. A method of localizing bearing contact to compensate for misalignment was explored. The proper choice of shaft support stiffness enabled good load sharing in the split torque transmission design. Face-gear experimental studies were also included and the feasibility of face gears in high-speed, high-load applications such as helicopter transmissions was demonstrated.
Experimental Investigation of Equilibrium Loads in a Planetary Reducer by Oil Film Calculations
Authors: Weiqiang Liu 
Published: March 2021

Abstract
In this paper, some properties of equilibrating load mechanism by oil film are analysed. Loads on the three planet gears are measured by telemeter at the same time. The load distribution laws among planet gears are given under the different torque and rotation rate. A good function of equilibrating load, along the tooth width, is found in testing model machine.
Optimal Design of Compact Spur Gear Reductions
Authors: Savage M. , Lattime S. B. , Kimmel J. A. , Coe H. H. 
Published: March 2021

Abstract
The optimal design of compact spur gear reductions includes the selection of bearing and shaft proportions in addition to the gear mesh parameters. Designs for single mesh spur gear reductions are based on optimization of system life, system volume, and system weight including gears, support shafts, and the four bearings. The overall optimization allows component properties to interact, yielding the best composite design. A modified feasible directions search algorithm directs the optimization through a continuous design space. Interpolated polynomials expand the discrete bearing properties and proportions into continuous variables for optimization. After finding the continuous optimum, the designer can analyze near optimal designs for comparison and selection. Design examples show the influence of the bearings on the optimal configurations.
Effect of Cutter Performance on Finished Tooth Form in Gear Shaving
Authors: Moriwaki I. , Fujita M. 
Published: March 2021

Abstract
The authors have been developed a computer simulation program of gear shaving. In the present paper, a new cutting model of shaving process is proposed so as to incorporate an effect of a cutting performance of shaving cutter into the simulation program. In this cutting model, it is assumed that a tooth flank material of work gear can be removed only when a depth of cut of a cutting edge exceeds a certain criterion. It is also assumed that the criterion have no definite value but has the nominal distribution over the tooth surface. The mean value of the distribution can define a characteristic of cutting performance of shaving cutter. The small mean value means that even small depth of cut can cause a stock removal; i.e. a good cutter performance. The computer simulations on gear shaving are performed to reveal the effect of the cutter performance on shaved tooth form. Under the conditions used in these simulations, the pressure angle error on the shaved tooth profile becomes remarkable as the cutter performance becomes worse. Thus, the developed computer simulation program of gear shaving has a reliability on the prediction of shaved tooth form. It will be useful for design of shaving cutter, judgement of tool life, and so on.
A Comparison Between Theoretical Prediction and Experimental Measurement of the Dynamic Behavior of Spur Gears
Authors: Rebbechi Brian , Forrester B. David , Oswald Fred B. , Townsend Dennis P. 
Published: March 2021

Abstract
A comparison was made between computer model predictions of gear dynamic behaviour and experimental results. The experimental data were derived from the NASA gear noise rig, which was used to record dynamic tooth loads and vibration. The experimental results were compared with predictions from the Australian Defence Science and Technology Organisation Aeronautical Research Laboratory’s gear dynamics code, for a matrix of 28 load-speed points. At high torque the peak dynamic load predictions agree with experimental results with an average error of 5 percent in the speed range 800 to 6000 rpm. Tooth separation (or bounce), which was observed in the experimental data for light-torque, high-speed conditions, was simulated by the computer model. The model was also successful in simulating the degree of load sharing between gear teeth in the multiple-tooth-contact region.
Tooth Contact and 3-D Stress Analysis of Involute Helical Gears
Authors: Arikan M. A. Sahir , Tamar Mustafa 
Published: March 2021

Abstract
An involute helical gear tooth is modelled by using helical gear geometry and a solid modelling package, and this model is used to determine the load distribution on contact lines of mating teeth, and to make the stress analysis by using three-dimensional tetrahedron finite elements with four nodes.
Tooth contact analysis is made by using the theory of gearing. Geometry of the cutting tool is used to determine the surface equations of the pinion and the gear in their own coordinate systems, then these equations are transformed to a fixed coordinate system to make the tooth contact analysis and to find the coordinates of contact points. Found contact point coordinates are then transformed back to the original coordinate systems and contact lines on helical gear teeth are formed. Results of this analysis is used to determine the application points and directions of the forces acting on the tooth. Then the stiffnesses of meshing teeth and the load distributions on contact lines are found, which are then used for stress analysis.
Optimum Design of a Gearbox for Low Vibration
Authors: Inoue Katsumi , Townsend Dennis P. , Coy John J. 
Published: March 2021

Abstract
A computer program was developed for designing a low vibration gearbox. The code is based on a finite element shell analysis method, a modal analysis method, and a structural optimization method. In the finite element analysis, a triangular shell element with 18 degrees-of-freedom is used. In the optimization method, the overall vibration energy of the gearbox is used as the objective function and is minimized at the exciting frequency by varying the finite element thickness. Modal analysis is used to derive the sensitivity of the vibration energy with respect to the design variable. The sensitivity is representative of both eigenvalues and eigenvectors. The optimum value is computed by the gradient projection method and a unidimensional search procedure under the constraint condition of constant weight.
The computer code is applied to a design problem derived from an experimental gearbox in use at the NASA Lewis Research Center. The top plate and two side plates of the gearbox are redesigned and the contribution of each surface to the total vibration is determined. Results show that optimization of the top plate alone is effective in reducing total gearbox vibration.
An Extended Model for the Analysis of the Dynamic Behavior of Planetary Trains
Authors: Saada A. , Velex P. 
Published: March 2021

Abstract
An extended model for determining dynamic tooth loads on spur and helical gear planetary trains is proposed. Torsional, flexural and axial generalized displacements of all the components are considered and a finite element procedure is used for generality.
In order to avoid modulations between meshing pulsations and the carrier angular velocity, equations are written relative to rotating frames fixed to satellite centers. Depending on their architectures, complex drives are broken down in basic 12 degree of freedom elements, namely:
- external gear element (sun-satellite element)
- internal gear element (ring-satellite element)
- pin-carrier element
- classical elements for shafts, bearings, couplings, ...
Details are given for elementary stiffness matrices. Due to contact conditions between mating teeth, these matrices are full and torsional, bending and traction effects are coupled.
State equations point to parametrically excited differential systems with gyroscopic contributions. A first application of the model is conducted on a 3 satellite epicyclic drive whose gyroscopic terms are neglected. Potentially dangerous frequencies for sun-satellite and satellite-ring contacts are determined and contributions of the environment of the planetary train are discussed. Numerical results underline the influence of satellite-carrier links on critical frequencies for tooth loading.
Composite Technology in Couplings and Shafting for Power Transmission
Authors: Fromknecht Thomas G. 
Published: March 2021

Abstract
Composite technology is growing in the power transmission industry. Composite structures of predominately carbon fibers and epoxy resins form a matrix structure for which one use is to transmit mechanical power. Of significant importance in this paper is the use of composite structures for shafting and coupling flexible elements.
Filament wound composite shafting consists of winding a continuous band of the carbon fiber and epoxy resin matrix around a mandrel to obtain optimized end product characteristics. These optimized characteristics include: minimized weight with superior tensile strength when compared to steel, variable modulus of elasticity for critical speed requirements, virtually no thermal expansion of the composite shaft and corrosion resistance. The ability to modify the wind angles during the manufacture of the composite shaft permits the designer to achieve desirable system characteristics through variations in the composite matrix or laminate with negligible change in component cost or delivery.
Coupling flexible elements are also manufactured from carbon fiber and epoxy resin laminates. These flexible elements take advantage of the greater tensile strength of the carbon fiber versus carbon or stainless steels to achieve a superior torque capacity within a given coupling outside diameter, or greater power density with equivalent or greater misalignment capacities. The carbon fiber and epoxy resin composite coupling flexible element embodies the desirable coupling characteristics of low deflection stiffnesses resulting in low reaction forces transmitted to the connecting equipment, with minimized possibility of fretting fatigue and significant corrosion resistance.
This paper will provide an overview on the composite structure, the materials used, the filament winding process, other manufacturing processes and the application and benefits of this technology in mechanical power transmission.
Gear Case Shape and Rib Distribution for Reducing Automobile Transmission Gear Noise
Authors: Maruyama N. , Morikawa K. , Hitomi N. 
Published: March 2021

Abstract
This paper deals with an analysis of gear case shape and rib distribution with the aim of reducing automobile transmission gear noise. Modal analysis results and FEM calculations are presented to show that the vibration characteristics of the transmission case are basically determined by its cross section shape. A case with a cocoon section shape, composed of two curved planes, is shown to have greater plane stiffness, resulting in higher natural frequencies and a smaller number of modes in the 0–5 KHz bandwidth. It is concluded that, in order to raise the natural frequency of vibration of a plate mode, a reinforcement rib should be placed orthogonally to the bending direction at the antinode. A simplified formula for estimating natural frequencies with respect to the relationship between flat and ribbed plates is proposed.
Improvement in Surface Fatigue Life of Hardened Gears by High-Intensity Shot Peening
Authors: Townsend Dennis P. 
Published: March 2021

Abstract
Two groups of carburized, hardened, and ground spur gears that were manufactured from the same heat of vacuum-induction-melted vacuum-are-remelted (VIM-VAR) AISI 9310 steel were endurance tested for surface fatigue. Both groups were manufactured with a standard ground 16-rms surface finish. One group was subjected to a shot-peening intensity of 7 to 9A, and the second group was subjected to a shot-peening intensity of 15 to 17A. All gears were honed after shot peening to a surface finish of 16 rms. The gear pitch diameter was 8.89 cm (3.5 in.). Test conditions were a maximum Hertz stress of 1.71 GPa (248 ksi), a gear temperature of 350 K (170 °F), and a speed of 10 000 rpm. The lubricant used for the tests was a synthetic paraffinic oil with an additive package. The following results were obtained: The 10-percent surface fatigue (pitting) life of the high-intensity (15 to 17A) shot-peened gears was 2.15 times that of the medium-intensity (7 to 9A) shot-peened gears, the same as that calculated from measured residual stress at a depth of 127 μm (5 mil). The measured residual stress for the high-intensity-shot-peened gears was 57 percent higher than that for the medium-intensity-shot-peened gears at a depth of 127 μm (5 mil) and 540 percent higher at a depth of 51 μm (2 mil).
Effect of Operating Conditions on Gearbox Noise
Authors: Oswald Fred B. , Zakrajsed James J. , Townsend Dennis P. , Atherton William , Lin Hsiang Hsi 
Published: March 2021

Abstract
Low-contact-ratio spur gears were tested in the NASA gear-noise rig to study the noise radiated from the top of the gearbox. The measured sound power from the gearbox top was obtained from a near-field acoustic intensity scan taken at 63 nodes just above the surface. The sound power was measured at a matrix of 45 operating speeds and torque levels. Results are presented in the form of a spectral speed map and as plots of sound power versus torque (at constant speed) and as sound power versus speed (at constant torque). Because of the presence of vibration modes, operating speed was found to have more impact on noise generation than torque level.
A NASA gear dynamics code was used to compute the gear tooth dynamic overload at the same 45 operating conditions used for the experiment. Similar trends were found between the analytical results for dynamic tooth overload and experimental results for sound power. Dynamic analysis may be used to design high-quality gears with profile relief optimized for minimum dynamic load and noise.
Experimental Investigation of the Impact Force That Occurs When a Roller Seats on the Sprocket During Normal Operation of a Roller Chain Drive
Authors: Conwell James C. , Johnson Glen E. , Peterson S. W. 
Published: March 2021

Abstract
As a roller “seats” onto a sprocket, an impact force occurs between these two elements due to the relative velocity between the roller and the sprocket tooth recess. This impact force is of interest because it can be related to chain noise, vibration, wear, and other phenomena of practical concern in the performance of chain drives. The magnitude of the impact force is equal to the product of the effective mass, the relative velocity, and the reciprocal of the time associated with the impact event. Unfortunately, it is difficult to estimate the effective mass, relative velocity, and appropriate impact time in order to estimate the impact force.
In this paper we present the results from a recent experimental investigation of this impact force. The experimental procedure is described, and data are presented for a wide range of initial tensions, transmitted loads, and chain speeds. As might be expected, impact force increases rapidly with increases in chain speed. An empirical relation for impact force as a function of chain speed and chain tension is presented and general observations about the data are presented and discussed.