Mechanical Engineering Commons^™

A Three-Dimensional Finite Element Stress Analysis Of Interface Conditions In Porous Coated Hip Prosthesis, Siu-For Yau

Theses

A three-dimensional finite element model of a collar-type hip stem and both the cortical and cancellous bones is used to investigate the stress distributions on an implanted femoral stem, adjacent bone, and specifically at the bone/implant interface for various amounts of porous coating and different stem materials. The finite element model consists of 909 nodes comprising 536 linear eight-node solid brick elements and 176 two-node interface elements. The finite element analysis code employed is SUPERTAB from SDRC. The interface elements consist of coincident-node spring elements and gap elements which model the rigidly bonded and loose interfaces respectively. Local coordinate systems …

Nontraditional Machining Techniques With Emphasis On Waterjet Milling, Shiv K. Kunapuli

Theses

The rapid growth of harder and difficult-to-machine materials over the past two decades necessitates the development of compatible nonconventional machining techniques, as detailed in this work, with special emphasis on one of the most recent machining method, the abrasive-waterjet technique(AWJ).

The feasibility of using AWJ for milling on glass is investigated. Due to the large number of parameters involved in the AWJ technique, and the multitude of machining requirements, optimization of performance is the focus. These parameters include waterjet pressure, particle size, abrasive flow rate, traverse rate and number of passes.

Surface topography is found to be a function of …

Development Of A Classification And Coding System For Computer-Aided Process Planning, Shilpan K. Patel

Theses

The chore of this work was to develop a Group Technology Classification Code which can represent the full gamut of simple, rotational parts. The automated coding plan is developed to alleviate the endeavor of the process planner to plan the tasks related to the manufacturing of a specific part. The 15 digits were devised from the Japanese KK-3 Classification and Coding system. The KK-3 System contains 21 digits. Our aim is to minimize the code length, and concurrently to eliminate the redundancies. As a result, a 15 digit G.T. Code is created. The proposed plan also generates the operation logic …

Dynamic Analysis Of The Generalized Slider Crank, Sahidur Rahman

Theses

A numerical technique is used to analyze the kinematics of the generalized slider crank mechanism and an analytical technique to derive dynamic force equations for that mechanism has been formulated. The numerical technique used for displacement analysis is based on a combination of Newton-Raphson and Davidon-Fletcher-Powell optimization algorithm using dual-number coordinate-transformation matrices. Velocity analysis is performed by using a dual number method. Finally, dynamic force analysis is accomplished on the basis of the dual-Euler equation and D'Alembert's principle. The approach is developed in such a manner that a digital computer can detect when a solution is possible and then solve …

Off-Line Programming Using Igrip, Narahari K. Bhandary

Theses

AT&T's FWS-200 (Flexible Work Station) has been modeled and simulated to implement Off-Line Programming (OLP). IGRIP (Interactive Graphics Robot Instruction Program) from Deneb Robotics, Inc. has been used to simulate the FWS operation.

A GSL(Graphics Simulation Language) program has been used to simulate the chip placements during PCB assembly. The program leads the user through the motions of chip placement, and after the simulation run downloads the motion sequence to the FWS. The animation sequences of the FWS have been downloaded to the FWS on the Factory Floor using a C program, which is utilized to communicate the data to …

Effect Of Shrinkage On The Design And Manufacture Of Plastic Parts In Injection Molding Using Cad/Cam Techniques, Deepak M. Shastri

Theses

Computer aided design software in injection molding has revolutionized injection molding in the design and manufacturing processes. Computer Aided Engineering can be applied to injection molding to increase the process efficiency, reduce part costs, and produce accurate parts in less time. The mold designer has many software programs to choose from to produce satisfactory mold designs from part geometries, and a correct selection can produce profitable results. A study of the need for and the scope of computers in injection molding is performed to evaluate the suitability of a CAE package by considering the value added to the parts using …

Implementation Of Automated Assembly, Kang H. Kong

Theses

Research has shown that about 60 - 80% wealth producing activities is related to manufacturing in major industrial countries.

Increased competition in industry has resulted in a greater emphasis on using automation to improve productivity and quality and also to reduce cost.

Most of the manufacturing works such as machining, painting, storage, retrieval, inspection and transportation have changed to automation successfully, except assembly. Manual assembly is predominant over automatic assembly techniques due to inherent assembly problem and the fact that the assembly machines lack the innate intelligence of human operator and lack sufficient flexibility to changeover when product designs and …

Size Reduction Of Polymeric Particulates By Jet Milling, Cheng Hua

Theses

A basic theory for the size reduction operation by jet milling has been developed.

Typical samples of feedstock have been analyzed using screen analysis to determine the initial distribution of polymeric particulate sizes prior to jet milling.

A statistical theory .was developed using probabilities to represent the likelihood that specific size reductions would occur. These probabilities include the effects of various equipment.

The theory was then used to predict the distribution of polymeric particulate sizes after jet milling. The agreement between the predictions and actual results was within 5 %.

Encouraged by the successful work of the simulation of the …

Design For Manufacturability, Kocherlakota Sreedhar

Theses

Design for Manufacturability represents a new awareness of the importance of design as the first manufacturing step. It recognizes that a company cannot meet all its objectives with isolated design and manufacturing operations. The Design for Manufacturability approach embodies certain underlying imperatives that help maintain communication between all components of the Manufacturing and Design system and permit flexibility to adopt and to modify design during each stage of the product realization. Design for Manufacturability cannot be bought or sold and it should be implemented by management. Complete support of management to the implementation is very important to the success of …

Design For Manufacturability : Re-Design Of Pencil Sharpener For The Ease Of Assembly, Amit R. Rathod

Theses

A Design For Manufacturability (DFM) approach is used to analyze the existing design of a pencil sharpener, and to reduce and re-design the parts of pencil sharpener for the ease of assembly. The procedure for the selection of a suitable and economical assembly method is based on the Boothroyd and Dewhurst methods. Analysis of the initial design for manual assembly and re-design for automatic as well as manual assembly is presented. An algorithmic approach for simplified generation of all mechanical assembly sequences and selection of the assembly sequences is presented using De Fazio and Whitney approach.

A Process For Implementing Cim In A Small Manufacturing Facility, Tushar R. Desai

Theses

This work is dedicated to small manufacturing enterprises seeking to explore Computer Integrated Manufacturing (CIM) technology, which is the recent trend in the manufacturing world. The main theme of this thesis is to improve productivity, product quality and reliability, and to reduce costs by integrating various discipline in small manufacturing environment, using computer technology.

To achieve this goal, a hypothetical small manufacturing company was chosen as a subject. The typical functional and organizational structures were analyzed and possible problem areas were highlighted. The problems relating to manufacturing process were studied in detail, and possible solutions were proposed to computerize the …

Expert System For Blown Film Extrusion, Jiachyi Li

Theses

Expert systems and blown film extrusion are two subjects to deal with in this thesis. Expert systems are an aspect of artificial intelligence, or a computer's ability to think. The determination of a suitable expert system for particular problem is an important factor in current societies. Blown film is extruded as a continuous tube which is air cooled, collapsed, and wound onto a roll as a double layer of film. Such film, if heat sealed and perforated, makes a roll of bags. There are many factors that affect blown film extrusion. Therefore, using expert system to evaluate blown film extrusion …

Application Of Expert System For Control Of Heating Distribution Network : A Case Study, Jun Li

Theses

The use of an expert system for the heating distribution network is an application of artificial intelligence to the domain of energy engineering.

The development of an expert system for a heating distribution network is explained. The expert system is implemented through the software Kee. The expert system is used to monitor the heating distribution network, and to complement some functions of the controls such as balancing the system pressure, stabilizing output, in addition to fault diagnosis, system process simulation. It serves also as a medium to system moniting, and operator training. Many other functions will be developed on the …

Analysis Of The Effects Of Wear And Tear Of Gates And Runners In The Injection Molding Process For Multi-Cavity Injection Molds In Natural Imbalance, Krishna Siva Rama Vellanki

Theses

Intuition, prior experience, and trial and error experimentation have previously been the key factors in solving the mold design and process optimization problems, when there is a dimensional change in gates and runners due to wear and tear in multi-cavity injection molding. The effect of wear and tear of gates and runners of circular and rectangular geometries, using the flow analysis package MOLDFLOW have been studied. A mold with two rectangular cavities of volume in the ratio 2:1 has been taken as the reference model for the analysis. It is observed that the amount of imbalance due to wear and …

Automated Computer Drafting Of Precision Tooling For Drawing Operation, Basani Venkateswarlu

Theses

Based on customer requirements of components, design engineers create the necessary tooling using CAD to produce the exact part desired by the customer. A software package using CARL is developed to help the design engineer to create the drawings of Pinch off Punch and Pinch off for both rectangular/square and round punches. A variety of hole patterns for the punches are automatically created through the software, along with a possibility of selecting one of the standard patterns automatically for a drawing. The drawings are created such that the dimensions and the notes are automatically generated with the input of the …

Development Of Plasma Ion Nitriding Process Parameters To Increase Durability Of Machine Components, Wenge Yang

Theses

In this work glow discharge ion nitriding process was selected to increase durability of machine components. To achieve this goal, the process parameters were designed, established and optimized based on the desired surface properties. The orthogonal experiment method is used to optimize multifactors process parameters. Using the image analyzing approach the microstructure of differently treated materials were obtained and analyzed. Developed coating layers, including different nitrides such as Fe3N, Fe4N, and diffusion zone were controlled by the optimized process parameters. Analysis of the obtained microstructure and microhardness showed the improvement of surface mechanical properties. Performed wear testing experiments showed increased …

Genetic Algorithm For Solving Printed Circuit Board Assembly Planning Problems, Hermean Wong

Theses

The application of the genetic algorithm for solving the planning problems for various printed circuit board assembly machines is presented. The genetic algorithm finds the sequence of component placement/insertion and arrangement of feeders simultaneously, for achieving the shortest assembly time. Three types of assembly planning problems are modeled such that they can be solved by the genetic algorithm. The algorithm uses links (parents) to represent possible solutions and applies genetic operators to generate new links (offspring) in an iterative procedure to obtain the optimal solution. Some examples are provided to illustrate the solutions generated by the genetic algorithm, and these …

Modification Of Wear Testing Methodology, Muhammed Farooq

Theses

In this work the existing computer controlled methodology has been modified A loading and unloading mechanism has been designed, manufactured and assembled. A specimen fixture has been designed and installed. Alloy steel specimens with different surface treatment were tested on the modified wear testing machine. Operational surface roughness was measured in all stages of running-in, steady state and catastrophic wear. The difference between technological and operational surface roughness was observed. The results show that the surface treatment by Plasma Ion-Nitriding with Magnetic treatment increases wear resistance. It was found that the coated material which had been magnetically treated with a …

Numerical Simulation Of The Heating Of Glass Mat Thermoplastic (Gmt) By Combined Conduction And Dual Beam Microwave Source Terms, Shrenik Kasturi

Theses

Fabrication of parts from glass mat thermoplastic involves the heating of the composite to a temperature above the melting point of the matrix iesin to obtain a low viscosity and to allow sheets to be molded without fractui ing. The focus of this work is this heating stage, particularly the influence of a source term in the energy equation.

The solution to this physical situation is complicated by the nature of the GMT sheet, which has a layeied structure, with diffeient thermophysical properties in different layers. The use of source terms has not been reported yet. and is the piimary …

Implementation Of A Production Planning And Control System In A Small Manufacturing Company, Carmelo Pernice

Theses

This thesis analyzed and discussed the implementation of a production control system in a small manufacturing firm. The basic concepts of production control were provided to give insight on the methodologies typically applied in production control systems. Overviews were presented on Material Resource Planning, Capacity Planning, and Shop Floor Control, as well as any supporting methodologies and technologies.

As with any project, some investigation was done in order to choose a system which best suits the company's needs. At Teledyne Adams, The DCD Shop Floor Control System was chosen since it is capable of handling batch manufacturing as well as …

Interfacing Plasticating Extruders With Personal Computers For Data Acquisition, Information Analysis And Retrieval Purposes, Gautamkumar Y. Shah

Theses

The current manufacturing industries are influenced more and more by computers and automation. Two of the major areas of computer uses are data acquisition and interfacing, both lead towards automation.

The intent of this thesis is to focus on the area of interfacing personal computers with plasticating extruders for information retrieval and storage. The requirements for software and hardware are discussed. Analysis of the stored information can be used to improve the quality of the final product. Implications of the stored parameters on the final product are also discussed. A sample program to store and retrieve the important parameters is …

Design For Assembly : Re-Design Of An Electrical Switch For The Ease Of Automatic Assembly, Achyuta Reddy Pannala

Theses

A design for assembly (DFA) method is used to analyze the existing design of parts of an electrical switch, and to reduce and re-design them, for the ease of automatic assembly. The procedure for the selection of suitable and economical assembly method is presented based on the Boothroyd & Dewhurst methods. Analysis of the initial design for manual assembly and the re-design for automatic assembly are presented. An algorithmic approach for simplified generation of all mechanical assembly sequences and selecting the good assembly sequences is presented with graphical representations. A work station needed for the automatic assembly is developed, which …

Analysis Of The Influence Of Natural Wear And Tear In Gates And Runners On The Filling Of A Balanced Multi-Cavity Injection Mold, Ranga Reddy V. Adavelly

Theses

Design of injection molds is outmost important in the manufacture of parts. Its components runners and gates significantly influence the mold filling. Using a simulation package for injection molding a balanced multi-cavity mold was designed. Wear in the gates of runner was simulated by varying the cross-sectional area of the components. Influence of wear of tear in gates of runners on mold filling was measured in terms of flow rate of time of fill. Detailed analysis is done on four different models using four different materials Polycarbonate, Polypropylene, Nylon6 and Polybutylene terephthalate. Graphical display of result is presented and analyzed …

Development Of An Adaptive Fuzzy Shell Clustering Algorithm And Validity Measures, Kurra Bhaswan

Theses

In objective functional based fuzzy clustering algorithms the weighted sum of the distances of the feature vectors from cluster prototype are minimized. The fuzzy memberships are utilized as weighing factors. The cluster prototype can be a point or a line or a plane, etc. This work extends the recent concept of using curved prototypes by utilizing the Adaptive Norm Theorem proposed by Dave¹ to develop an algorithm for the detection of fuzzy hyper-ellipsoidal shell prototypes. The Objective functional associates a norm for each cluster in which to measure the proximity of the shell prototype adaptively. The resulting implementation necessitates …

Petri Net Modeling And Analysis Of An Fms Cell, Paresh A. Patel

Theses

Petri nets have evolved into a powerful tool for the modeling, analysis and design of asynchronous, concurrent systems. This thesis presents the modeling and analysis of a flexible manufacturing system (FMS) cell using Petri nets. In order to improve the productivity of such systems, the building of mathematical models is a crucial step.

In this thesis, the theory and application of Petri nets are presented with emphasis on their application to the modeling and analysis of practical automated manufacturing systems. The theory of Petri nets includes their basic notation and properties. In order to illustrate how a Petri net with …

Computer Graphic Simulation Of Sweeping Of Solid Objects, Jr-Jyun Jang

Theses

This thesis is on the computer graphic simulation of the swept volume of a solid object undergoing Euclidean motions (including translation and rotation). The study helps visualize different types of Euclidean motions and supports the previously developed swept volume theories by providing graphic realism.Included in the thesis presentation are the following :

1. Description of Euclidean motions of polyhedral objects, using ruled surfaces to represent swept volumes.
2. Representation of sweeping of solid objects, -using parametric cubic equation and sweep differential equation.
3. Simulation of motions of PUMA and IBM robots.
4. Wire-frame and shaded image displays of swept volumes.

Development Of Techniques Of Artificial Intelligence In Identifying The Different Machined Surfaces, Yi-Ching Chou

Theses

This thesis deals with the identification of different machined surfaces with artificial inteligence techniques. There are five kinds of machining operations: grinding, turning, milling, EDM and waterjet which determine the characteristics of resulting surfaces. Topology of various specimens is measured using the surfanylizer. Twenty one parameters are extracted from the measurements to describe the characteristics. In this thesis, we develop neural and expert systems that recoginize and classify surfaces according to the machining methods.

Some Aspects Of Integration Of Classification, Computer Aided Design, Process Planning, And Scheduling Of Flexible Manufacturing Systems, Suresh Godavari

Theses

This work deals with the role, problems and solution technique for integration of Computer Assisted Design, Classification, Process Planning, and Scheduling for a Flexible Manufacturing System. A lark spectrum of rotational and prismatic parts are considered.

A Knowledge-based rough classification and coding system [C&C] has been developed for coding similar parts using a Group Technology [GT] technique. In this module VP-EXPERT and DBase III Plus are used as expert system and database respectively. This module interfaces with a database for the retrieval and selection process.

The code obtained from the C&C system is the basis for the succeeding phases. The …

Deposition Of Particles In A Channel With Gravity And Image Forces, Jing-Shiun Lai

Theses

Deposition of particles in a parallel-plate channel under the influence of inertia, fluid viscosity, gravity and image forces was studied using trajectory method.

A laminar fluid flow of uniform and parabolic (or fully-developed) velocity profiles is assumed and the fluid is suspended with particles having the same velocity as the fluid at the inlet plane. The particles flowing into a horizontal parallel-plate channel have no initial velocity in the vertical direction. The influence of gravity force and image force produces a vertical motion which results in deposition of particles on the channel walls.

A trajectory method was employed to find …

Experimental Study Of The Internal Loads In A Cardan Joint, Johannes K. Waal De

Theses

A recent investigation by Fischer and Freudenstein questioned the validity of the negligible axial forces assumption in the static force analysis of Cardan Joints. The purpose of this paper is to experimentally assess this assumption for the dynamic case.

To this end an experiment was constructed to determine the axial forces acting on the intermediate revolute joints of a Cardan joint. A four-square test arrangement was prepared such that shaft intersection angle, shaft torque, and shaft speed could be varied. Strain gages were applied to the "arms" of the joint to measure the resulting strains due to the forces along …