Engineering Commons^™

Theoretical Analysis Of Universal Joint With Manufacturing And Assembly Tolerances, Xiaosong Liu

Theses

The model for a Cardan joint with manufacturing and assembly tolerances is a spatial four-bar mechanism with one rotating and three cylindrical joints. In this thesis, dual-number coordinate transformation matrices and Newtonian mechanics are applied to provide a concise description of the kinetics of the universal joint. The dual-Euler equations are used to derive the dynamic equations of the Cardan joint. The analytical technique presented here yields explicit expressions. It will provide the designer with better insight into the workings of the kinematics and dynamics of the Cardan joint.

The equations of statics and dynamics of the frictionless universal joint …

On-Line Dot Matrix Code Verification, Thatta V. Premnath

Theses

Machine vision principles are increasingly applied in the areas of manufacturing and automated inspection. The objective of this thesis work is to investigate different methods that could be implemented for matching printed dot matrix characters with the actual characters to be printed.

In support to this investigation, a survey of various methods proposed by researchers in the field of Optical Character Recognition (OCR) is presented. Survey includes a detailed description of the state-of-the art methods. It is shown that due to restrictions of hardware cost and the time available to inspect each character, the standard approaches are not practical. Hence, …

Test 1628: John Deere 4455 Quadrange Diesel 16-Speed, Nebraska Tractor Test Lab

Nebraska Tractor Tests

EXPLANATION OF THE TEST PROCEDURE General Tractors are tested at the University of Nebraska according to the Agricultural Tractor Test Code approved by the American Society of Agricultural Engineers and the Society of Automotive Engineers or official Nebraska test procedure. The manufacturer selects the tractor to be tested and certifies that it is a stock model. Each tractor is equipped with the common power consuming accessories such as power steering, power lift pump, generator, etc., if available. Power consuming accessories may be disconnected only when the means for disconnecting can be reached from the operating station. An official representative of …

Test 1626: John Deere 4055 Quadrange Diesel 16-Speed, Nebraska Tractor Test Lab

Nebraska Tractor Tests

EXPLANATION OF THE TEST PROCEDURE General Tractors are tested at the University of Nebraska according to the Agricultural Tractor Test Code approved by the American Society of Agricultural Engineers and the Society of Automotive Engineers or official Nebraska test procedure. The manufacturer selects the tractor to be tested and certifies that it is a stock model. Each tractor is equipped with the common power consuming accessories such as power steering, power lift pump, generator, etc., if available. Power consuming accessories may be disconnected only when the means for disconnecting can be reached from the operating station. An official representative of …

Xeriscape: Landscape That Saves, Florida Solar Energy Center, Carolyn King Burns

FSEC Energy Research Center®

Today's headlines trumpet urgent energy concerns. Still, there are ways in which individual effort cumulatively can slow, stop, and even reverse the negative impact of poor conservation habits.

Landscaping spends energy in a variety of ways: in the manufacture and use of fertilizers; in the manufacture, use, and fueling of landscaping equipment; in the production and distribution of our water supply; and in physical effort. But Xeriscaping saves energy.

With 800 - 900 people a day moving to the land of sunshine, water is increasingly precious. In Florida outdoor irrigation alone can consume up to 50 percent of the average …

A Comparative Study Of The Performance Of Various Image Analysis Methods For Dimensional Inspection With Vision Systems, Ralf Heinrich Koeppe

Dissertations and Theses

Dimensional inspection with Vision Systems requires a careful selection of image analysis methods in order to obtain accurate information about the geometry of the parts to be measured.

The purpose of this project is to study, implement and compare different image evaluation methods and to show their strengths and weaknesses with respect to dimensional inspection. Emphasis is made on the inspection of circular features. The criteria of comparison for these methods are discussed. Using synthetically generated images, various analysis methods are compared and conclusions for their use are drawn. Results of the comparison show that the selection of a method …

Explicit And Implicit Calculations Of Turbulent Cavity Flows With And Without Yaw Angle, Guan-Wei Yen

Mechanical & Aerospace Engineering Theses & Dissertations

Computations have been performed to simulate turbulent supersonic flows past three-dimensional deep cavities with and without yaw. Simulation of these self-sustained oscillatory flows have been generated through time accurate solutions of the Reynolds averaged complete Navier-Stokes equations using two different schemes: (1) MacCormack, finite-difference, (2) implicit, upwind, finite-volume schemes. The second scheme, which is approximately 30% faster, is found to produce better time accurate results. The Reynolds stresses have been modeled, using the Baldwin-Lomax algebraic turbulence model with certain modifications. The computational results include instantaneous and time averaged flow properties everywhere in the computational domain. Time series analyses have been …

Global/Local Stress Analysis Of Composite Structures, Jonathan B. Ransom

Mechanical & Aerospace Engineering Theses & Dissertations

A method for performing a global/local stress analysis is described and its capabilities are demonstrated. The method employs spline interpolation functions which satisfy the linear plate bending equation to determine displacements and rotations from a global model which are used as "boundary conditions" for the local model. Then, the local model is analyzed independent of the global model of the structure. This approach can be used to determine local, detailed stress states for specific structural regions using independent, refined local models which exploit information from less-refined global models. The method presented is not restricted to having a priori knowledge of …

Investigating The Method Of Structural Topological Variations For Sensitivity Analysis And Design Optimization, Niki A. Mehta

Mechanical & Aerospace Engineering Theses & Dissertations

The method of structural topological variations is a newly developed technique for analysis of frame structures. It provides a novel method that completely avoids formulating and solving simultaneous equations, required in the finite element displacement method. The principal objective of this thesis is to investigate the method of topological variations as a possible design tool and study its applicability in the sensitivity analysis and in the process of design optimization.

A computer code was developed for this method to obtain its comparative performance against the finite element displacement method. For analysis of large structures involving frequent local modifications, the method …

Numerical Study Of Three-Dimensional Separation And Flow Control At A Wing/Body Junction, Balakrishnan Lakshmanan

Mechanical & Aerospace Engineering Theses & Dissertations

The problem of three-dimensional separation and flow control at a wing/body junction has been investigated numerically using a three-dimensional Navier-Stokes code. The numerical code employs an algebraic grid generation technique for generating the grid for unmodified junction and an elliptic grid generation technique for filleted fin junction. The results for laminar flow past a blunt fin/flat plate junction demonstrate that after grid refinement, the computations agree with experiment and reveal a strong dependency of the number of vortices at the junction on Mach number and Reynolds number. The numerical results for pressure distribution, particle paths and limiting streamlines for turbulent …

A Reiner-Rivlin Fluid Flow Through Entrance Region Of A Circular Pipe, V. G. Masanja

Tanzania Journal of Engineering and Technology (TJET)

The flow of a Reiner-Rivlin fluid with two viscosity coefficients through the entrance region of a circular pipe has been studied numerically. In particular the growth of the entrance length as a function of the Reynolds number and the non-Newtonian parameters has been examined. Where comparison could be made, the results have been compared with existing experimental -and numerical data as well as the limited theoretical work available.

Test 1625: John Deere 8960 Powersync Diesel 12 And 24-Speed, Nebraska Tractor Test Lab

Nebraska Tractor Tests

EXPLANATION OF THE TEST PROCEDURE General Tractors are tested at the University of Nebraska according to the Agricultural Tractor Test Code approved by the American Society of Agricultural Engineers and the Society of Automotive Engineers or official Nebraska test procedure. The manufacturer selects the tractor to be tested and certifies that it is a stock model. Each tractor is equipped with the common power consuming accessories such as power steering, power lift pump, generator, etc., if available. Power consuming accessories may be disconnected only when the means for disconnecting can be reached from the operating station. An official representative of …

Development, Simulation, And Validation Of A Highly Nonlinear Hydraulic Servosystem Model, Tim W. Mclain, E K. Iversen, C C. Davis, S C. Jacobsen

Faculty Publications

A highly accurate and predictive dynamic model of an electrohydraulic actuation system has been developed and verified. The accuracy of the model can be attributed to the inclusion of nonlinear representations of many system elements including hysteresis and saturation effects, orifice areas, piston damping, and flow forces. This level of accuracy makes the model a potentially valuable tool in the analysis and design of electrohydraulic actuation systems.

Kinematic Synthesis Of Mechanisms For Multiply Separated Positions, Hyoung Jun Kim

Dissertations

The rigid body motion is studied in a combination of finitely and infinitesimally separated positions in planar, spherical, and spatial kinematics. A general new method for determining the locations of points and/or lines in a rigid body moving through finitely and infinitesimally separated positions is developed. These points and/or lines would satisfy the constraints of various types of binary links for planar, spherical, and spatial mechanisms.

A unified form of circle-point curve equation is derived for finitely and multiply separated position problems in planar and spherical motions. A graphical method to construct the circle-point and center-point curves and Ball point …

Close-Range, Noncontact Distance Measurement By Controlled Image Irradiance, Jaeho Kim

Dissertations

Dimensional measurement or check is a major part of the inspection and quality control in manufacturing. Most of the measurement applications are based on contact methods. While a number of non-contact methods are available, they are limited in accuracy, in flexibility, or in the range of application areas. An optical, close-range, non-contact distance measurement method has been developed for manufacturing and other applications. Based on a simple imaging principle, the method derives the distance information from the power response of a small axial image area, the irradiance of which is controlled by an active controlled illumination of the corresponding object …

Isoparametric Finite Elements For Linear Isotropic Micropolar Plate Bending, Vallanore K. Suresh

Dissertations

Finite element analysis programs for bending of linear isotropic micropolar elasticity are developed in this thesis. Isoparametric two-dimensional and three-dimensional elements are used to solve plate bending problems. Two-dimensional and three-dimensional finite element formulations are developed. Corresponding finite element programs are then developed. Patch tests are performed on the two-dimensional elements. Convergence studies are undertaken for the elements. Several plates are considered to evaluate the finite element scheme. The effects of the coupling factor N and characteristic length 1 are studied. A post processor with graphical display of displacements is developed.

Numerical results obtained for various plates are in good …

An Interactive Graphics Capability For Numerical Design Optimization, Abbay P. Joshi

Theses

Hierarchical Object Oriented Program Software [HOOPS] is used here to develop an interactive graphical interface for the design optimization program CADOP5. A preprocessor provides the user with button menu options. Using various buttons like Variable Button, Obj Button, Parameter Button, etc. the user can interactively define problem variables, parameters and limits as well as interactively modify the behavior and the constraint functions. The post processor displays variable values for three consecutive design cycle in the form of bar charts. Objective function values are plotted against the number of design cycle. Using this information the user can determine if the solution …

The Rate Of Vibrational Segregation In Particulate Materials, Yidan Lan

Theses

The rate of vibratory size segregation has been modeled in multi-component size systems as a process of mutual sorting between each size species. The concept of mutual sorting is introduced from which generalized expressions are derived for the rates of change of the local concentration of each size species. In a binary system, the expressions simplify to give the expected result that the segregation rates for the large and small particles are equal but of opposite sign. Also, in these systems, the segregation rate is described by measuring the rising speed of the interface between the small and large particles. …

A Robot Vision System For Determining 3-D Coordinates Of Object Points, Tea-Quin Kim

Theses

A stereo disparity algorithm is implemented on an industrial robot vision system. One camera manipulated by an industrial robot is used to obtain stereo images of an object. After a pair of stereo images are processed, the points of interest are selected from each image. The similarities of three types of feature characters are used to assign initial weights of the, matching probabilities to a set of point candidates. Then a relaxation method, which is based on probabilities of local connectivity, similarity of feature characters, and smoothness of matching, is used iteratively to improve the initial probabilities of image matching. …

Investigation Of Surface Formation In Abrasive Waterjet Cutting, Shy-Shyan Chen

Theses

This study is concerned with experimental and numerical investigation of the dynamics of surface generation during the impingement of the abrasive waterjet on a workpiece.

A series of erosion zones were generated by the abrasive waterjet on the polished surface of stainless steel samples. The impingement was carried out at different traverse speeds and abrasive flow rates. An optical, a scanning electron microscope and a laser displacement sensor were used to investigate the developed surface.

The microscopical examination of the surface enabled determination of the shape of asperities created by individual particles, distribution of asperities on the surface and the …

Investigation Of The Distribution Of Particles In An Abrasive Water Jet, Sun Kim

Theses

This study is concerned with the distribution of abrasive particles within an abrasive waterJet. The Jet is generated by the Ingersoll Rand nozzle set at the different diameters of the sapphire nozzles and carbide mixers. Water pressure is maintained at 4.7- 4.9 ksi.

The distribution of particles is examined by the separation of the central and adjacent part of the flow and the measurement of the fractions of the mixture and abrasive in the separated region. The separation is carried out by diamond washers coaxial with a carbide mixer. The second series of experiments involve the estimation of the Jet …

Design Of A Gear Driven Anti-Twister Mechanism For A Seal-Less Blood Processor, Ajit Nachiket Dastane

Theses

This thesis presents the design of a gear driven anti- twister mechanism for a blood cell separator. The anti- twister mechanism allows for continuous feed and discharge lines that are rigidly attached to the rotating centrifuge head, thus eliminating the need of rotating seals. It is anticipated that the device using a gear driven anti-twister mechanism will have smoother power transmission and closer rpm tolerances.

In addition, a procedure for the dynamic analysis of the existing device, which uses a belt-driven anti-twister mechanism, is developed. The experimental values obtained from the device are compared with the theoretical values obtained by …

Test 1623: John Deere 8560 Powersync Diesel 12 And 24-Speed, Nebraska Tractor Test Lab

Nebraska Tractor Tests

EXPLANATION OF THE TEST PROCEDURE General Tractors are tested at the University of Nebraska according to the Agricultural Tractor Test Code approved by the American Society of Agricultural Engineers and the Society of Automotive Engineers or official Nebraska test procedure. The manufacturer selects the tractor to be tested and certifies that it is a stock model. Each tractor is equipped with the common power consuming accessories such as power steering, power lift pump, generator, etc., if available. Power consuming accessories may be disconnected only when the means for disconnecting can be reached from the operating station. An official representative of …

Test 1624: John Deere 8760 Powersync Diesel 12 And 24-Speed, Nebraska Tractor Test Lab

Nebraska Tractor Tests

EXPLANATION OF THE TEST PROCEDURE General Tractors are tested at the University of Nebraska according to the Agricultural Tractor Test Code approved by the American Society of Agricultural Engineers and the Society of Automotive Engineers or official Nebraska test procedure. The manufacturer selects the tractor to be tested and certifies that it is a stock model. Each tractor is equipped with the common power consuming accessories such as power steering, power lift pump, generator, etc., if available. Power consuming accessories may be disconnected only when the means for disconnecting can be reached from the operating station. An official representative of …

Test 1617: John Deere 4055 Powershift Diesel 15-Speed, Nebraska Tractor Test Lab

Nebraska Tractor Tests

EXPLANATION OF THE TEST PROCEDURE General Tractors are tested at the University of Nebraska according to the Agricultural Tractor Test Code approved by the American Society of Agricultural Engineers and the Society of Automotive Engineers or official Nebraska test procedure. The manufacturer selects the tractor to be tested and certifies that it is a stock model. Each tractor is equipped with the common power consuming accessories such as power steering, power lift pump, generator, etc., if available. Power consuming accessories may be disconnected only when the means for disconnecting can be reached from the operating station. An official representative of …

Test 1619: John Deere 4455 Powershift Diesel 15-Speed, Nebraska Tractor Test Lab

Nebraska Tractor Tests

EXPLANATION OF THE TEST PROCEDURE General Tractors are tested at the University of Nebraska according to the Agricultural Tractor Test Code approved by the American Society of Agricultural Engineers and the Society of Automotive Engineers or official Nebraska test procedure. The manufacturer selects the tractor to be tested and certifies that it is a stock model. Each tractor is equipped with the common power consuming accessories such as power steering, power lift pump, generator, etc., if available. Power consuming accessories may be disconnected only when the means for disconnecting can be reached from the operating station. An official representative of …

Test 1622: John Deere 4955 And 4960 Powershift Diesel 15-Speed, Nebraska Tractor Test Lab

Nebraska Tractor Tests

EXPLANATION OF THE TEST PROCEDURE General Tractors are tested at the University of Nebraska according to the Agricultural Tractor Test Code approved by the American Society of Agricultural Engineers and the Society of Automotive Engineers or official Nebraska test procedure. The manufacturer selects the tractor to be tested and certifies that it is a stock model. Each tractor is equipped with the common power consuming accessories such as power steering, power lift pump, generator, etc., if available. Power consuming accessories may be disconnected only when the means for disconnecting can be reached from the operating station. An official representative of …

Test 1618: John Deere 4255 Powershift Diesel 15-Speed, Nebraska Tractor Test Lab

Nebraska Tractor Tests

EXPLANATION OF THE TEST PROCEDURE General Tractors are tested at the University of Nebraska according to the Agricultural Tractor Test Code approved by the American Society of Agricultural Engineers and the Society of Automotive Engineers or official Nebraska test procedure. The manufacturer selects the tractor to be tested and certifies that it is a stock model. Each tractor is equipped with the common power consuming accessories such as power steering, power lift pump, generator, etc., if available. Power consuming accessories may be disconnected only when the means for disconnecting can be reached from the operating station. An official representative of …

Test 1620: John Deere 4555 And 4560 Powershift Diesel 15-Speed, Nebraska Tractor Test Lab

Nebraska Tractor Tests

EXPLANATION OF THE TEST PROCEDURE General Tractors are tested at the University of Nebraska according to the Agricultural Tractor Test Code approved by the American Society of Agricultural Engineers and the Society of Automotive Engineers or official Nebraska test procedure. The manufacturer selects the tractor to be tested and certifies that it is a stock model. Each tractor is equipped with the common power consuming accessories such as power steering, power lift pump, generator, etc., if available. Power consuming accessories may be disconnected only when the means for disconnecting can be reached from the operating station. An official representative of …

Test 1621: John Deere 4755 And 4760 Powershift Diesel 15-Speed, Nebraska Tractor Test Lab

Nebraska Tractor Tests

EXPLANATION OF THE TEST PROCEDURE General Tractors are tested at the University of Nebraska according to the Agricultural Tractor Test Code approved by the American Society of Agricultural Engineers and the Society of Automotive Engineers or official Nebraska test procedure. The manufacturer selects the tractor to be tested and certifies that it is a stock model. Each tractor is equipped with the common power consuming accessories such as power steering, power lift pump, generator, etc., if available. Power consuming accessories may be disconnected only when the means for disconnecting can be reached from the operating station. An official representative of …