Mechanical Engineering Commons^™

Fixture For Carbon Fiber Spar Of Human Powered Helicopter, David John Ikeda, Luis Gonzalez

Industrial and Manufacturing Engineering

The following report describes our contribution to Cal Poly Human Powered Helicopter for the 2012 competition for the Sikorsky Prize offered by the American Helicopter Society. In order to win this prize the team needs to build and fly a human powered helicopter for more than 60 seconds reaching and altitude of 3 meters while staying in a 10 meter square box. Our team was created to support the integration of Carbon Fiber parts, specifically the carbon fiber spars with rotor and landing gears. Precise cutting and accurate drilling was needed and our team was tasked with creating a fixture …

Ole Miss Engineer 2013-2014

Ole Miss Engineer

No abstract provided.

Loading Path Determination For Tube Hydroforming Process Of Automotive Component Using Apdl, E. Masoumi Khalil Abad, Amir Ghazanfari, R. Hashemi

Faculty Publications, Mechanical Engineering

In this study, an extended stress-based forming limit diagram (FLD) for prediction of necking based on the Marciniak and Kucznski (M-K) model is represented and applied in tube hydroforming. The bulge forming of a straight tube is simulated by finite element method and verified with published experimental data. This adaptive simulation technique is based on the ability to detect the onset and growth of defects (e.g., bursting and wrinkling) and to promptly readjust the loading paths. Thus, a suitable load path is determined by applying Adaptive Simulation Method in ANSYS Parametric Design Language (APDL).

Crack Growth Behavior Under Creep-Fatigue Conditions Using Compact And Double Edge Notch Tension-Compression Specimens, Santosh B. Narasimha Chary

Graduate Theses and Dissertations

The American Society for Testing and Materials (ASTM) has recently developed a new standard for creep-fatigue crack growth testing, E 2760-10, that supports testing compact specimens, C(T), under load controlled conditions. C(T) specimens are commonly used for fatigue and creep-fatigue crack growth testing under constant-load-amplitude conditions. The use of these specimens is limited to positive load ratios. They are also limited in the amount of crack growth data that can be developed at high stress intensity values due to accumulation of plastic and/or creep strains leading to ratcheting in the specimen. Testing under displacement control can potentially address these shortcomings …

Design And Construction Of An Omni-Directional Soccer Ball Thrower, Andrew James Marquette

Undergraduate Honors Capstone Projects

Introduction

We are ODST the Omni-Directional Soccer Ball Thrower team which designed the soccer ball launching machine. Working in direct correlation with the project sponsor John Meade from Athlonic Sports this is the report outlining the soccer ball thrower. John from Athlonic Sports came up with the overall project and initial project vision. There are soccer ball launching machines on the market but lacking mobility, not amiable and are heavy. The design needed to be mobile, amiable, lightweight, and have a soccer ball capacity incorporated into the machine. This will allow coaches to repeatability place the soccer ball in certain …

Physics Trick - Balanced Can, Said Shakerin

All Faculty Articles - School of Engineering and Computer Science

The ordinary 12-oz beverage cans in the figures below are not held up with any props or glue. The bottom of such cans is stepped at its circumference for better stacking. When this kind of can is tilted, as shown in Fig. 1, the outside corners of the step touch the surface beneath, providing an effective contact about 1 cm wide. Because the contact is relatively wide and the geometry is symmetrical, it is easy to balance an empty can by simply adding an appropriate amount of water so that the overall center of mass is located directly above the …

The Effects Of Wrist Orthoses On The Stiffness Of Wrist Rotations, Daniel Brad Seegmiller

Theses and Dissertations

Wrist orthoses are the most common upper limb orthoses, being used by thousands of individuals each year to stabilize, immobilize, or support the wrist joint. Wrist orthoses achieve their function by altering the stiffness of the wrist joint (Figure 1-1). However, there is no quantitative understanding of how wrist orthoses affect wrist stiffness, and consequently, wrist orthosis development often relies on feel, intuition, or empirical heuristics rather than a methodical, quantitative approach. Because wrist movement control is dominated by wrist joint stiffness (Charles and Hogan 2011) a quantitative understanding of how wrist orthoses alter the stiffness of the wrist is …

Subway Rail Car Filter Sampling Tool, Brian Hong, Julia Pollard, Philip Ybarra

Mechanical Engineering

The following design report has been prepared by Team Slice for both Cal Poly’s Mechanical Engineering Department and Lawrence Livermore National Laboratory. This report provides an overview of the design ideation process of creating a subway rail car filter sampling tool. This cutting tool will take samples of HVAC filters from subway railcars in New York City, NY. These samples will then be used for processing in biological terror emergency response situations. This device will provide an easy, safe, and user friendly tool to cut filter samples. The current method of cutting is a pair of scissors or shears, which …

Computer Controlled Vegetable Oil Fuel System, Joseph W. Souza

Mechanical Engineering

No abstract provided.

Development And Validation Of A Human Knee Joint Finite Element Model For Tissue Stress And Strain Predictions During Exercise, Spencer D. Wangerin

Master's Theses

Osteoarthritis (OA) is a degenerative condition of cartilage and is the leading cost of disability in the United States. Motion analysis experiments in combination with knee-joint finite element (FE) analysis may be used to identify exercises that maintain knee-joint osteochondral (OC) loading at safe levels for patients at high-risk for knee OA, individuals with modest OC defects, or patients rehabilitating after surgical interventions. Therefore, a detailed total knee-joint FE model was developed by modifying open-source knee-joint geometries in order to predict OC tissue stress and strain during the stance phase of gait. The model was partially validated for predicting the …

Cae Methods On Vibration-Based Health Monitoring Of Power Transmission Systems, Brian Fang

Master's Theses

This thesis focuses on different methods to analyze power transmission systems with computer software to aid in detection of faulty or damaged systems. It is split into three sections. The first section involves utilizing finite element software to analyze gear stiffness and stresses. A quasi-static and dynamic analysis are done on two sets of fixed axis spur gears and a planetary gear system using ABAQUS to analyze the stress, strain and gear mesh stiffness variation. In the second section, the vibrational patterns produced by a simple bevel gear system are investigated by an experiment and by dynamic modeling in ADAMS. …

Active Learning Using Model-Eliciting Activities And Inquiry-Based Learning Activities In Dynamics, Jeffrey Phillip Georgette

Master's Theses

This thesis focuses on a year-long project of implementing active learning in undergraduate dynamics courses at Cal Poly San Luis Obispo from 2012-2013. The purpose is to increase conceptual understanding of critical dynamics concepts and to repair misconceptions of the students. Conceptual understanding in Dynamics is vital to understanding the big picture, building upon previous knowledge, and better understanding the behavior of engineering systems. Through various hands-on activities, students make predictions, test their conceptions, and solve real world problems. These active learning methods allow students to improve their learning of Dynamics concepts. Education research on active learning is present in …

Heat Transfer Experiment: Energy Conservation, Ben Ward, Brett Wallace, Ryan Waltman

Mechanical Engineering

This proposal, prepared for the Mechanical Engineering Department by the HTEC design team will redesign and replace the current energy conversion lab that is inaccurate and out of date. The team will evaluate methods of energy conversion, specifically using braking systems, as well as existing labs in order to design an accurate and relatable experiment for this lab. The project team will work with Professor Kim Shollenberger in order to design an experiment that demonstrates energy conversion through the first law of thermodynamics while utilizing a common device that is practical in student’s lives. The final result of this project …

Low-Cost Scheffler Solar Concentrator For The Developing World, Darren Sholes, Jason Morgan, Nicholas Fuller

Mechanical Engineering

This report will outline an approach to design, test, and build a low-cost Scheffler solar concentrator to be used for safer, sustainable and cost effective cooking in the developing world. The function of Scheffler concentrators and a proposed method to create one in an economic, environmentally conscious manner is summarized. If successful, the design will be presented in a way that is readily and freely available to anyone in the world. The authors have examined existing technology and researched the availability and cost of different materials. Analysis was performed in order to verify the feasibility of the different design ideas …

The Collapsible Trailer: Design And Manufacture, Robert Hobson

Biomedical Engineering

No abstract provided.

Ultrasonic Propagation And Scattering In Pearlitic Steel, Hualong Du

Department of Engineering Mechanics: Dissertations, Theses, and Student Research

Diffuse ultrasonic backscatter measurements have been especially useful for extracting microstructural information and for improving flaw detection in materials. In this dissertation, this approach is applied to inspection of railroad wheels. To improve the wear resistance, the tread surfaces of railroad wheels are usually quenched with water to increase the hardness. The pearlite phase of iron, characterized by alternating ferrite and cementite phases, is created by the quenching and the lamellar spacing within grains increases progressively from the quenched tread surface to deeper locations due to the non-uniform cooling rate. The quench depth is an important parameter governing the wheel …

Near-Infrared Surface-Enhanced Fluorescence Using Silver Nanoparticles In Solution, Michael D. Furtaw

Department of Mechanical and Materials Engineering: Dissertations, Theses, and Student Research

Fluorescence spectroscopy is a widely used detection technology in many research and clinical assays. Further improvement to assay sensitivity may enable earlier diagnosis of disease, novel biomarker discovery, and ultimately, improved outcomes of clinical care along with reduction in costs. Near-infrared, surface-enhanced fluorescence (NIR-SEF) is a promising approach to improve assay sensitivity via simultaneous increase in signal with a reduction in background. This dissertation describes research conducted with the overall goal to determine the extent to which fluorescence in solution may be enhanced by altering specific variables involved in the formation of plasmonactive nanostructures of dye-labeled protein and silver nanoparticles …

Structural And Magnetic Characterization Study Of Hfco7 Alloy With Substitutions Of Si, Ti, Fe, Mn And B, Jacob A. Lewis

Department of Mechanical and Materials Engineering: Dissertations, Theses, and Student Research

Magnetic materials are a critical component of the modern technological society. The market of high-energy product hard magnets is dominated by the rare-earth element containing neodymium-iron-boron (NdFeB) magnets. As a result of worldwide demand coupled with trade restrictions on rare-earth minerals, new magnet compositions are explored to reduce pressure on the already strained market. The hafnium-cobalt alloy system has shown promise as a candidate for filling the gap in saturation magnetization between rare-earth containing alloys and those made with abundant elements. This study explores the magnetic effects of silicon, titanium, iron, manganese and boron substitutions in the hafnium-cobalt-7 (1:7 atomic …

Experimental Study On The Effect Of Air Flow On Soap Bubble Formation, John M. Davidson

Department of Mechanical and Materials Engineering: Dissertations, Theses, and Student Research

Soap bubbles are a common interfacial fluid dynamics phenomenon having applications such as buoyant hollow spherical fillers and flow visualization of large scale airflows. In contrast to the dynamics of liquid drops in gas and gas bubbles in liquid, the dynamics of soap bubbles has not been well documented, possibly because soap bubbles have gas-liquid-gas interfaces. Having the thin-liquid-film interface seems to alter the characteristics of the bubble/drop creation process. Thus, the main objective of this study is to experimentally examine how airflow develops and interacts with the soap liquid film as the film stretches and finally collapses to pinch-off. …

Phonon Transport Analysis Of Semiconductor Nanocomposites Using Monte Carlo Simulations, Mayank Malladi

All Theses

Nanocomposites are composite materials which incorporate nanosized particles, platelets or fibers. The addition of nanosized phases into the bulk matrix can lead to significantly different material properties compared to their macrocomposite counterparts. For nanocomposites, thermal conductivity is one of the most important physical properties. Manipulation and control of thermal conductivity in nanocomposites have impacted a variety of applications. In particular, it has been shown that the phonon thermal conductivity can be reduced significantly in nanocomposites due to the increase in phonon interface scattering while the electrical conductivity can be maintained. This extraordinary property of nanocomposites has been used to enhance …

Analyzing Requirement Type Influence On Generated Solutions, Emily Worinkeng

All Theses

Several ideation methods are available and used by engineering designers to enable the generation of alternative designs [1]. However, there has been little work done to understand the role that the design problem given to participants plays in the ideation process. The contribution of this research is found through the proposed guidelines with respect to the type of requirements to include as part of the design problem in order to achieve the desired quantity, quality, novelty, and variety of solutions during the early stages of the design process. This work is the first attempt at analyzing the effect of requirement …

A Study Of Gallery Method To Increase Idea Quality In Conceptual Design, Liz Mathew

All Theses

The objective of this research is to evaluate whether gallery method increases idea quality in conceptual design for engineering design problems. The gallery method is a group ideation process which allows individuals to first generate ideas individually, followed by pooling of ideas to conduct group ideation. Design engineers are often encouraged to work in groups to generate concepts and solutions for design problems. However, past research argues that individual ideation results in higher quality design concepts compared to the group ideation methods. The limitations of group ideation such as free riding, production blocking, evaluation apprehension, and goal incongruity are identified …

An Exploratory Study On The Effects Of Goal Alignment, Interventions, And Motivational Factors On Innovative Engineering Design Projects, Blake Linnerud

All Theses

Innovation has become an important facet of engineering design, both in industry and the academy. Many senior-level engineering design courses encourage students to develop innovative solutions to open design projects from industry sponsors. Like industry, these academic problems are tackled by teams of students. Student teams that function at the highest level are more likely to reach the innovative solutions for which they are searching. The research presented in this work focuses on two main areas: (1) understanding what motivates engineers when working on innovative design projects and (2) determining the effects of goal alignment interventions on design teams working …

Knowledge Extraction From Work Instructions Through Text Processing And Analysis, Abhiram Koneru

All Theses

The objective of this thesis is to design, develop and implement an automated approach to support processing of historical assembly data to extract useful knowledge about assembly instructions and time studies to facilitate the development of decision support systems, for a large automotive original equipment manufacturer (OEM). At a conceptual level, this research establishes a framework for sustainable and scalable approach to extract knowledge from big data using techniques from Natural Language Processing (NLP) and Machine Learning (ML). Process sheets are text documents that contain detailed instructions to assemble a portion of the vehicle, specification of parts and tools to …

Effects Of Iteration On Concept Development, Shivraj Ranganathan

All Theses

Iteration in the conceptual design stage is defined as repetition of design tasks to incorporate new information. A more concise definition of iteration relevant to this research would be the progression of design through different abstraction levels or design stages, defining and refining design solutions while progressing from initial concepts to a more detailed design. Although it is believed that iteration has a positive effect on the quality of ideas in the design process, this experimental study presents an opportunity to determine the effects of iteration on quality of concepts and the factors that lead to increased quality of concepts. …

Knowledge Base Representation With Axiomatic Design Rules For Concept Level Up Implement In Ontological Framework, Zhuochen Shi

All Theses

Axiomatic Design has been applied and developed as a tool, offering a scientific basis for design and improving design activities. Axiomatic Design has been used in various fields such as software system design, structure design, and product design. However, several challenges and limitations exist in Axiomatic Design including: the inconsistency in identifying design parameters, existence of coupled design, and multiple groups of functional requirements and design parameters. Aimed at using Axiomatic Design to generate conceptual solutions in engineering design while overcoming its limitations, a formal ontology is developed. The ontology defines functional requirements, design parameters, concepts, components and variables and …

Implementation And Analysis Of A 1.4l Turbo Liquid Cooled Cac And Ac Condenser System, Mitchell Zajac

Masters Theses

This project report serves as a continuation and finalization of an overall experience with the design process including working on the development of system components, working with automotive industry leaders, suppliers and dealing with the aspects of business and production feasibility. The development of a dual level cooling concept to apply Centro Richerche Fiat established components on a Chrysler Group vehicle application was the foundation of the design project completed in December 2012 by Matt Cutler and Mitch Zajac. The development of this system aimed to decrease overall vehicle power consumption, minimize overall system packaging space, and to increase vehicle …

Effects Of Time Varying Background Noise Conditions On Human Perception And Performance, Andrew H. Hathaway

Durham School of Architectural Engineering and Construction: Dissertations, Theses, and Student Research

This thesis was designed to study the effects of changing noise conditions on human perception and performance. In two phases, participants were exposed to a number of noise conditions and their performance on an arithmetic task involving short-term memory was monitored and their subjective perception of noise conditions was collected via questionnaires.

In the first phase, participants were tested while being subjected to RC-29(H) and RC-47(RV) conditions created by broadband noise fluctuating on different time intervals, resembling the changing noise conditions potentially found in modern HVAC systems. These intervals varied from two minutes to ten minutes. Results show a significant …

Experimental Investigation Of The Active Flow Control On A Two-Dimensional Wind Turbine Airfoil, Guannan Wang

Dissertations - ALL

Wind turbine blades experience unsteady aerodynamic loading under various off-design conditions. The fatigue loading reduces the operational time of the wind turbine hence leads to an increase in the Cost of Energy (CoE) of the wind power. In this study, active flow control with unsteady blowing actuators was applied to a two-dimensional wind turbine airfoil to alleviate the unsteady aerodynamic loading and improve the aerodynamic performance, particularly under large scale freestream disturbances. A low speed, open jet aeroacoustic wind tunnel was designed and constructed based on an existing anechoic chamber for this investigation. A theoretical analysis based on a Blade …

In-Bottle Wine Aerator, Kevin Kesler, Patrick Lowry, Paul Woolworth

Mechanical Engineering

The proposal for Capitol Cultivators discusses and evaluates the development of an in-bottle wine aerator. It defines the problem and need for an aerator located inside the wine bottle. Additionally, it outlines requirements essential for an effective design and describes the engineering process that will be followed.