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A Decision Support System For The Equipment Selection Of Robotic Manufacturing Cells, Lars Johan Resare

Theses

Considering the principles of concurrent engineering, a Decision Support System (DSS) is developed to aid in the equipment selection of robotic manufacturing cells. The objective is to synchronously and simultaneously select proper equipment for the cell to provide efficient performance, subject to operational and budgetary constraints.

The DSS consists of several modules, including a data base that houses the specifications of equipment available in the market place, a first cut selection module, and an optimization engine. In its development, the optimization scheme utilizes analytical models and algorithms that capture different sources of variability in production, such as tolerances, clearances and …

Design Improvement Using Reverse Analysis In Design For Quality Manufacturability, Vikram V. Datla

Theses

The competitive needs of modern manufacturing demands that innovative approaches be used to gain an edge over the competitors. least Product design is one of the key dimensions wazzu in which companies can excel. Shortening the product design cycle so as to rapidly launch defect free products, is the goal of most companies. Design for Quality Manufacturability (DFQM) is a technique used to evaluate the quality manufacturability of a product at the design stage, so as to eliminate quality problems during production.

DFQM provides a means for relating the activities of quality improvement, product design and manufacturability analysis. The basis …

Two-Echelon Logistics Model For Recoverable Items With Lateral Supply In The Army., Kwanghui. Chai

Electronic Theses and Dissertations

This paper develops a Two-echelon logistics model for recoverable items with lateral supply in a single period in the Army. It derives formulas for distribution and inventory costs, and determines the optimal stock level at a depot and at a base to minimize the backorders. During the period, a Poisson demand and distinct units of operating bases which stocks can be shared are assumed. It allows the lateral supply between operating bases. A two-phase method is used to get solutions to the stock level constrained optimization problem. The outcome of this paper can be applied to lower level of logistics …

A 0-1 Integer Programming Model For The Simultaneous Allocation Of Operations Of Part Types And Grouping Of Machine-Tool Combinations., Franklin Samuel Jaiselvan. Foulger

Electronic Theses and Dissertations

In today's competitive world, for manufacturers to survive in the market and to compete on a global level, several innovative strategies are being developed and practised. In industries which manufacture a variety of products in lots, one of the well known manufacturing strategies or systems is cellular manufacturing systems (CMS). CMS has several advantages especially for manufacturers who produce a medium variety of products in medium volumes. The tangible benefits are reduction in cycle time of the product, reduced inventory, improved quality, possibility to meet customer demands on time etc.; the intangible benefits are flexibility in the system, increased control …

Scheduling In A Dual Resource Constrained System Using Genetic Algorithms., Vishvas. Patel

Electronic Theses and Dissertations

In this research a solution methodology and a software program system for assignment of dual resources (Machines and Workers) were developed. By considering two dual resource constrained problems as the candidate problems, an optimized GA based heuristic was developed. First genetic algorithms were used to determine the optimal staffing level which can be viewed as a basic design decision. Second, genetic algorithms were used to make short range control decisions regarding the operations of dual resource constrained shop. Six different dispatching rules such as SPT, EOPNDD, EDD, FCFS, LSO, LPT and eight performance criteria were used. The performance of each …

Smart Drilling: A Computer-Based System For Planning Drilling Operations., Jia. Ma

Electronic Theses and Dissertations

In this thesis, a prototype computer aided process planning system--Smart Drilling System is presented. The system will be able to automatically generate plans for multiple hole drilling process, such as tool selection, drilling sequence, and etc. The system contains four modules: (1) Tool selection module, (2) Machining condition design module, (3) NC code generation module, and (4) Simulation module. In the tool selection module, a generative searching and planning algorithm is applied. Fuzzy logic was utilized to make decisions in tool selection. The module can group the drills according to their size and shape, and select optimal drills that will …

Prediction Models For The Integration Of New Technology Into The Automotive Manufacturing Infrastructure., Leo Paul. Oriet

Electronic Theses and Dissertations

With the introduction of increasingly expanded world markets in the 1990's, manufacturers are now obliged to compete with the best the world has to offer. Human infrastructures working with robust, capable and in-control processes depend on comprehensive appraisal of the Ergonomic implications for new technologies introduced in manufacturing operating systems. These core values and beliefs are now becoming part of a tightly linked decision-making process which is now being increasingly utilized by most successful manufacturers of world class products. World class manufacturers will welcome and integrate new technologies with the human infrastructure and do whatever it takes for worker protection. …

Thickness Measurement Of Curved Multilayered Polymer Structures Using The Ultrasonic Pulse-Echo Method., Hong. Shao

Electronic Theses and Dissertations

Ultrasonic inspection is accomplished by using electronically controlled pulses introduced into a material from an outer surface. Then, the ultrasonic energy travels within the material, finally reaching again an outer boundary. Material condition is diagnosed from characteristics of the receive ultrasonic energy. The technique of using ultrasonic pulse echo to investigate and examinate the thickness of curved multilayered structures will be presented in this thesis. It also studied physics conditions which the curvatures of multilayered polymer systems might effect thickness measurements. The real location of the focus of an acoustic beam in curved layered structures was calculated by a ray-optical …

Modelling The Allocation Of Pallets In A Flexible Manufacturing Cell., Balakrishnan. Baskar

Electronic Theses and Dissertations

Pallets are an essential part of manufacturing operations. This research concentrates on pallets for machining and, in particular, pallets for use in a flexible manufacturing cells (FMC). Flexible manufacturing has received widespread attention in the modern manufacturing environment. A close look at the research done on different areas of flexible manufacturing shows that the aspect of pallets in the design stage has been neglected. The objective of this research, therefore, is to develop mathematical programming models which deals with the palletizing problem in flexible manufacturing. The models assume that there is a set of existing machines in a manufacturing shop …

The Effect Of Elbow Position And Grip Span On Isometric Grip Strength And Force Distribution Of Fingers., Xuewei (Sue). Chen

Electronic Theses and Dissertations

Injuries to the hand, lower arm, and shoulder are often attributed to inappropriate use or poor design of hand tools. Isometric grip, performed with the angled handles of pliers was investigated in this study. For this thesis, three factors were studied. They were grip type (traditional and reversed grip), elbow position (0$\sp\circ$, 30$\sp\circ$, 60$\sp\circ$, 90$\sp\circ$, and 120$\sp\circ$), and grip span (50, 60, and 70 mm). The resultant forces between the jaws of the pliers and finger forces were measured under each condition. The purpose of this study was to evaluate the effect of elbow position and grip span on grip …

Comparison Of Tactile Probe Cmm And Laser Scanning Techniques For Reverse Engineering., Yan. Liu

Electronic Theses and Dissertations

In this thesis, the strategies of reverse engineering using tactile probe CMM and laser scanning techniques are described and applied in practice. Examples are given by reverse engineering geometric primitives including a plane, a sphere and a two-radius cylinder as well as free-form surfaces including a car tail light and a manifold surface. Through these examples, the effect of the probing angle of the laser scanner as well as the CMM on the accuracy of the measurement data is revealed. The problems with surface modeling are studied and the solutions to build a surface model from different geometry curves with …

A Model Of Operation Allocation With Lot Splitting In Flexible Assembly Systems., Fazlullah. Sharief

Electronic Theses and Dissertations

In this thesis, the loading problem in Flexible Assembly Systems (FASs) has been studied. Two integer programming models of the loading problem are presented. The first model is an extension of an earlier 0/1 integer programming model which takes into consideration the unit transportation costs. The total cost in model 1 thus is a summation of assembly costs and unit transportation costs. An operation in a FAS may be performed at more than one station. However, this capacity is not fully explored and taken advantage of if the complete production requirements of an assembly are sent to one station only …

A Study Of The Life Cycle Assessment Of Multilayer Plastic Fuel Tank., Dan. Albu

Electronic Theses and Dissertations

One of the objectives of the Life Cycle Assessment (LCA) is to evaluate environmental burdens associated with a product, process or activity by quantifying energy and materials used and wastes released to the environment. The assessment includes the entire life cycle of the product encompassing raw material processing, manufacturing, transportation, use, recycling and disposal. This paper analyzes the multilayer plastic fuel tank from the LCA perspective, determines the main environmental burdens and expands the analysis on the improvement areas of the product for the purpose of lowering the environmental burdens. Many companies in the private sector are beginning to see …

An Object-Oriented Fuzzy Expert System For The Design Of Rotating Operations., Xin. Yuan

Electronic Theses and Dissertations

In the thesis, a prototype object-oriented fuzzy expert system called SAM (Smart Assistant to Machinist) is presented for rotating cutter selection and cutting condition design. Object-Oriented Design and Programming Methods are employed to construct and implement the system. Based on partial and imprecise information, the system is able to select rotating cutter products available in current commercial market, and design cutting conditions for an optimized objective. The system consists of four modules: a database, a rule base, a cutter selection module and a cutting condition design module. The database consists of six kinds of data files: machinability of workpieces, machining …

Optimal Automotive Door-Body Fitting For Body-In-White Assembly., Essam. Shalash

Electronic Theses and Dissertations

Flexible manufacturing is a multi-faceted term that has been used in the automotive industry to imply a multitude of manufacturing criteria. A prominent area of application for such criteria in the automotive industry is the body assembly process. The assembly process is, in turn, divided into a number of sub-processes which include fitting car doors to body openings. As these operations take place before the painting of the car body, they are commonly known as Body in White processes. The door fitting problem is ranked within the top issues of car-quality, since an inadequate door fit causes water leakage, wind …