Mechanical Engineering Commons^™

Optimization Constrained Cad Framework With Iso-Performing Design Generator, Kelly Eric Bowman

Theses and Dissertations

Design decisions have a large impact early in the design process. Optimization methods can help engineers improve their early decision making, however, design problems are often ill-posed for optimization at this early stage. This thesis develops engineering methods to use optimization during embodiment design, despite these difficulties. One common difficulty in designing mechanical systems is in handling the effects that design changes in one subsystem have on another. This is made more difficult in early engineering design, when design information is preliminary. Increased efforts have been made to use numerical optimization methods in early engineering design – because of the …

Bio-Surfaces And Geometric References For A Standardized Biomechanical Design Methodology For Mass Customization, Kimberly A. Jensen

Theses and Dissertations

This dissertation presents a method for the design of customizable products that interface with the human body. The method presented involves first, a consistent method of capturing and representing the human model so that the model can be used with CAx tools and solid modeling techniques. Second, it provides a design methodology based on feature structure planning and assembly modeling that provides a consistent structure to the design process so that it can be reused and parameterized. Third, a strategy for identifying parametric variables that are referenced to the human body is introduced. The core of this method is the …

A Scientific Foundation Of Collaborative Engineering, S. C.-Y. Lu, W. Elmaraghy, G. Schuh, R. Wilhelm

Department of Mechanical and Materials Engineering: Faculty Publications

Collaborative engineering is the practical application of collaboration sciences to the engineering domain. In today’s highly connected technology-driven economy, the production industry must rely on the best practices of collaborative engineering to stay competitive when designing, manufacturing, and operating complex machines, processes, and systems on a global scale. Despite its importance, collaborative engineering is currently more of a practiced art than a scientific discipline. A better understanding of how engineers should collaborate with all stakeholders to accomplish complex tasks that fulfill our increasing social responsibilities is a grand challenge. However, because we currently lack well-defined sciences of human collaboration, we …

Structuring Emperical Methods For Reuse And Efficiency In Product Development Processes, Marshall Edwin Bare

Theses and Dissertations

Product development requires that engineers have the ability to predict product performance. When product performance involves complex physics and natural phenomena, mathematical models are often insufficient to provide accurate predictions. Engineering companies compensate for this deficiency by testing prototypes to obtain empirical data that can be used in place of predictive models. The purpose of this work is to provide techniques and methods for efficient use of empirical methods in product development processes. Empirical methods involve the design and creation of prototype hardware and the testing of that hardware in controlled environments. Empirical methods represent a complete product development sub-cycle …

An Evaluation Of Attributes And Competencies For Manufacturing Engineering Technology Graduates, Loni S. Williamson

Theses and Dissertations

The purpose of this study is to determine the required attributes and competencies required for a graduate from a manufacturing engineering technology baccalaureate program. A document called “Competencies of Manufacturing Engineering Technology Graduates” was compiled in October 2004. This document lists twelve attributes thought to be important for MET graduates: Leadership, Professionalism, Creativity and Problem Solving, Management, Materials, Processes, Quality, Systems, Design, Communication, Safety and Environmental Issues, and Global Awareness. Under each attribute is a list of five to seven competencies creating a total of seventy-three competencies for graduates of an MET baccalaureate program. This list of attributes and competencies …

Flexible Tools For Specifying Design Variation, Trichy Pasupathy, Xiaoping Zhao, Robert Wilhelm

Department of Mechanical and Materials Engineering: Faculty Publications

This paper describes flexible tools for specifying design variations that are based on nonuniform profile tolerance definitions. These tools specify bounds of design performance that can be used for negotiation among engineers in a collaborative design process. These specification methods allow for the capture of many different design functions that are not easily described with current tool designs. In addition, these specification methods lend themselves to efficient verification methods. Profile tolerance definitions provide the most general variation controls for complex mechanical surfaces. Common design practices and engineering standards for profile tolerances exhibit many weaknesses and limitations. We present a rationale …

Techniques In The Design Of Thermomechanical Microactuators, Larry L. Howell, Timothy W. Mclain, Michael S. Baker, Christian D. Lott

Faculty Publications

The purpose of this chapter is to provide fundamental background for the design of thermomechanical microactuators. Actuation has been a particularly challenging aspect of microsystem development. Many actuation approaches used at the macro level, such as hydraulics, pneumatics, electric motors, internal combustion engines and turbines, are either too difficult to fabricate at the micro level or do not work well at that scale. Electrostatic attraction is one approach that has been widely used for actuation of microsystems; however, electrostatic actuators tend to have high voltage requirements and low output force capabilities. While electrostatic actuation is suitable for many applications, some …

Design Optimization Module For Hierarchical Research And Learning Environment, Oktay Baysal, Mehti Koklu, Ahmed K. Noor

Mechanical & Aerospace Engineering Faculty Publications

The present paper describes a learning module on design optimization courses within a hierarchical research and learning network (HRLN). In this environment a knowledge organization can be created as a hierarchical learning network to link diverse inter- and trans- disciplinary teams from a consortium of universities, industry, government agencies and the providers of learning technologies. It is an approach that builds on computer-based training, intelligent tutoring systems, interactive learning, collaborative-distributed learning, and learning networks. The present design optimization module has been developed and described herein, as a demonstrator of a learning module in this environment. This module allows for the …

Microstructure Design Of A Two Phase Composite Using Two-Point Correlation Functions, Brent L. Adams, H. Garmestani, G. Saheli

Faculty Publications

This work has been funded under the AFOSR Grant no. F49620-03-1-0011 and Army Research Lab contract no. DAAD17-02-P-0398 and DAAD 19-01-1-0742. Two-point distribution functions are used here as to introduce "Microstructure Sensitive Design" in two-phase composites. Statistical distribution functions are commonly used for the representation of microstructures and also for homogenization of materials properties. The use of two-point statistics allows the composite designer to include the morphology and distribution in addition to the properties of the individual phases and components. Statistical continuum mechanics is used to make a direct link between the microstructure and properties (elastic and plastic) in terms …

Incorporating Functionally Graded Materials And Precipitation Hardening Into Microstructure Sensitive Design, Mark Edward Lyon

Theses and Dissertations

The methods of MSD are applied to the design of functionally graded materials. Analysis models are presented to allow the design of compliant derailleur for a case study and constraints are placed on the design. Several methods are presented for relating elements of the microstructure to the properties of the material, including Taylor yield theory, Hill elastic bounds, and precipitation hardening.

Applying n-point statistics to the MSD framework is also discussed. Some results are presented for the information content of the 2-point correlation statistics that follow from the methods used to integrate functionally graded materials into MSD.

For the compliant …

Tools And Metrics For Evaluating Modular Product Concepts Based On Strategic Objectives, Matthew Bailey Strong

Theses and Dissertations

The design of modular products has recently become the focus of significant research in the area of design theory and methodology. This focus is the result of increased awareness of the potential power of modularity to achieve certain product objectives. However, there continues to be a gap between the results of academic research and industrial application. The refinement, consolidation, and extension of this academic research would help design teams who are charged with developing modular products to use these academic findings in real world, industrial applications. The research presented in this document focuses on developing design tools, based on past …

The Effects Of Patch Properties On The Debonding Behavior Of Patched Beam-Plates, Anette M. Karlsson

Mechanical Engineering Faculty Publications

The debonding characteristics of patched structures are investigated in this study by means of an analytical model. In particular, the effects the lay-up sequence and edge tapering of a carbon-reinforced epoxy patch, as well as the beveling of an aluminum patch, have on the initiation, stability, and extent of the debonding are considered. The results presented show that both the degree of edge-tapering and the patch properties must be carefully selected in order to optimize the patched structure. It is also shown that when designing a patched system, it is important to model the correct boundary and load conditions to …

A New Autonomous Underwater Vehicle For Imaging Research, C. Roman, O. Pizarro, R. Eustice, H. Singh

Christopher N. Roman

Currently, unmanned underwater vehicles either tend to be cumbersome and complex to run, or operationally simple, but not quite suitable platforms for deep water imaging. This paper presents an alternative design in the form of a new low cost and easier to use autonomous underwater vehicle (AUV) for imaging research. The objective of the vehicle is to serve as a readily available and operationally simple tool that allows rapid testing of imaging algorithms in areas such as photomosaicking, 3D image reconstruction from a single camera, image based navigation, and multi-sensor fusion of bathymetry and optical data. These are all current …

Analytical And Experimental Study Of Investment Casting With Laser Stereolithography Models, Wen-Long Yao

Dissertations

This dissertation presents an analytical and experimental investigation of ceramic shell cracking during the burnout process in investment casting with internally webbed laser stereolithography (SLA) patterns. Included in the consideration are the cracking temperature of the ceramic shell, the web link buckling temperature, and the glass transition temperature of the epoxy resin. The hypothesis is that shell cracking will occur when the cracking temperature is lower than the glass transition temperature and the web buckling temperature.

An analytical and experimental study has been conducted, with the cross-sectional area, the span length of the web structure, and the shell thickness being …

Dual Adaptive Recumbent Trike, Jason V. Eastman

Undergraduate Honors Capstone Projects

The DART team's objective was to develop a tandem recumbent tricycle that would be economical, easy to build, and adaptable. This would involve designing, building and testing the tricycle.

Parameter Optimization For Curl Distortion In Building Parts Using 3-D Laser Stereolithography, Laurel A. Hanesian

Theses

The curl distortions in rapid prototyping using 3-D laser stereo lithography occur as the top layers shrink after being drawn and attaching to the bottom layers. The amount of curl is dependent upon the how much shrinkage the layer has finished prior to adhesion. It is also dependent on how deep the cure of the top layer amounts to as it adheres into the bottom layer. This thesis investigated the effect of build parameters on the distortions associated with the diagnostic 'Letter-H' shaped test part. The same parameters were also considered in a time optimization study, using calculated, predicted results …

Design And Design Centers In Engineering Education, Clive L. Dym

All HMC Faculty Publications and Research

This paper is intended to be the opening salvo of the workshop, Computing Futures in Engineering Design (Dym, 1997). Thus, I want to take this privileged moment to ask you to think with me about the role of design in engineering. In particular, I want to reflect upon how design is articulated and how design is taught; about the role of design in engineering education and in the practice of engineering; and about the role that could be played locally and, perhaps, nationally by a center devoted to design education. Because I teach here at Harvey Mudd College (HMC), …

Design For Quality Manufacturability Analysis Of Missing/Misplaced Parts And Part Interference, Altaf Yusuf Tamboo

Theses

Design for Quality Manufacturability (DFQM) is an approach that addresses the issue of quality manufacturability (QM) - the likelihood that defects will occur during manufacture of a product in a standard plant. The DFQM methodology is based on the premise that defects found in assembled products are often influenced by some features of the design and/or assembly process (influencing factors). These influencing factors cause defects in the presence of certain error catalysts.

One of the influencing factors is geometrical features such as shape and symmetry. A classification scheme for part shape and symmetry is developed. This scheme is summarized in …

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.

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 …

Novel Rotary-Turbo-Inflow Tech - Gearturbine Project - Featured Development, Carlos Barrera

Carlos Barrera

GEARTURBINE PROJECT Atypical InFlow Thermodynamic Technology Proposal Submission Novel Fueled Motor Engine Type

*State of the art Innovative concept Top system Higher efficient percent. Have similar system of the Aeolipile Heron Steam device from Alexandria 10-70 AD. -New Form-Function Motor-Engine Device. Next Step, Epic Design Change, Broken-Seal Revelation. -Desirable Power-Plant Innovation.

YouTube; * Atypical New • GEARTURBINE / Retrodynamic = DextroRPM VS LevoInFlow + Ying Yang Thrust Way Type - Non Waste Looses

-This innovative concept consists of hull and core where are held all 8 bteps of the work-flow which make the concept functional. The core has several gears …

Design, Calibration, And Application Of A Sensor For Measuring Time Dependent Angle Of Attack Of Helicopter Blades, Weiyuan Henry Liu

Mechanical & Aerospace Engineering Theses & Dissertations

Various pressure probes were designed and tested which could be attached to helicopter blades when a helicopter is in flight. The pressure probes consisted of spherical heads which were held in place by cylindrical shanks. Built inside the heads were transducers to measure the pressure differential between pressure ports which were located on the front portion of the spherical head facing the airstream. Data was obtained over a range of airstream velocity of 11,6 to 88.4- m/s (38 to 290 ft/sec), corresponding to Reynolds numbers of 0.24 to 1.84x10⁵ based on the sphere diameter. Both static and dynamic tests …

Designing Yards For Sheep, Department Of Agriculture, Western Australia

Journal of the Department of Agriculture, Western Australia, Series 4

This article has been adapted from a report of the 1976 Sheep and Wool Refresher Course.

The officers attending the Course inspected W. A. farms, and then met in groups to discuss what they had seen, and to pool their experience in compiling a report. This article has been adapted from the report of the group working on the topic "Sheep yards and facilities".

The W. A. representative in the group working on sheep yard design was Mr John Wise of the Department's Katanning office.

The principals discussed here should help farmers either design new sheep yards, or improve the …