Mechanical Engineering Commons^™

Structural Analysis Of Integration Of A Non-Cylindrical Cng Fuel Tank, Prathamesh Prashant Deshpande

Dissertations, Master's Theses and Master's Reports - Open

The purpose of this study is to computationally model and analyze the vehicle frame which is mounted with a non-conventional, non-cylindrical compressed natural gas (CNG) fuel tank. Integration of this tank in the vehicle underbody will resolve the issue of reduced storage space which is observed in a conventional CNG powered vehicle. This research will ultimately result in making CNG a good alternative to gasoline and reducing the increasing dependency on a single fuel. This tank will be developed in two phases: phase I design of the tank will be a standard rectangular outer box shape with Schwarz P-surface inner …

Computational Fluid Dynamics Modeling Of The Effects Of Water Injection In A Diesel Engine, Rabun Z. Wallace

College of Graduate Studies: Theses & Dissertations

Water injection has been used in internal combustion engines for many years. It has been used to cool combustion temperatures, reduce emissions, and in some instances clean carbon buildup from the cylinder. Research has shown that the water to fuel mass ratio is most effective between 20-30%, so the upper and lower limit were used for simulations in Converge CFD. To validate the CFD model, a case without water injection was compared to experimental data from Sandia National Laboratory. The predicted in-cylinder pressure and heat release rate showed good agreement with the experimental data. Cases were run with the injection …

Planning Freeform Extrusion Fabrication Processes With Consideration Of Horizontal Staircase Effect, Amir Ghazanfari, Wenbin Li, Ming Leu, Robert Landers

Faculty Publications, Mechanical Engineering

An algorithm has been developed to estimate the “horizontal” staircase effect and a technique is proposed to reduce this type of geometrical error for freeform extrusion fabrication processes of 3D “solid” parts. The adaptive rastering technique, proposed in this paper, analyzes the geometry of each layer and changes the width of each line of the raster adaptively in order to reduce the staircase error and increase the productivity simultaneously. For each line, the maximum width that results in a staircase error smaller than a predefined threshold is determined for decreasing the fabrication time or increasing the dimensional accuracy, or both. …

Cold Roll Extrusion Machine Redesign Final Design Report, Foja Bains, Bryan Cyr, David Van Schooten

Mechanical Engineering

This report is a comprehensive review of a redesign of subsystems for a Cold Roll Extrusion Machine, a forging operation, for PCC Rollmet. Three subsystems were addressed in this project: A new Loading system, Feed system, and Lubrication system. The Loading system, and support system during developmental design stages, addressed the timely loading process of pipes onto the forging machine. After two quarters of design iteration, the group decided on a lever arm, hydraulic actuated, loading design. In the final quarter of the project, a quarter scale model of this lever arm was constructed to prove the concept of the …

Farmbot, James Cruz, Scott Herrington, Bryan Rodriguez

Mechanical Engineering

The purpose of this project was to develop the hardware for the current Farmbot to perform its primary functions, and to create a template for a system that would be adaptable for future users and developers. The scope of the project included creating a universal tool mount, a seeding system, and a watering and nutrient mixing system. This project was brought to the students by sponsor Rory Aronson, the creator of Farmbot. The Cal Poly Farmbot team was able to go through an extensive brainstorming and iterative process for each part, where testing was able to be incorporated immediately due …

Wingtip Dynamics Simulator, Eugene Fox, Nick Rodriguez, Steven Rieber

Mechanical Engineering

Raytheon is a defense contracting company with an electronic warfare division that is developing a radio frequency signal triangulation system. Part of the focus in improving this technology is the need for accurate and real time locational knowledge of the signal receivers, which are located at the tips of aircraft wings. Due to turbulence during flight, the fluttering motion of the wings alter the distance and angle relationships of the two receivers and add noise to the received signal data, which negatively affect the triangulation estimates. To mitigate this error caused by the wing flutter, Raytheon is developing a software …

The Development Of A Laminated Copolyester Electric Guitar, Addison S. Karnes

Electronic Theses and Dissertations

This thesis is an investigation of the fabrication and assembly methodologies employed in the development of a proof-of-principle prototype electric guitar composed of laminated copolyester. The objective of the project was to develop the processes and procedures to create an optimized physical and visual bond between layers to minimize vibratory dissipation, thus maximizing sustain. A high speed CNC router, abrasive waterjet, laser engraver-cutter, as well as various manual fabrication and assembly methods were investigated in the construction of the guitar prototypes. The lamination processes explored include low-temperature, heat-assisted pressure bonding, solvent and chemical welding, and contact adhesives. The project concluded …

Experiment And Simulation Of The Acoustic Signature Of Fatigued-Cracked Gears In A Two-Stage Gearbox, Matthew James Ostiguy

Master's Theses

This thesis focuses on the development of a health monitoring system for gearbox transmissions. This was accomplished by developing and understanding a two-stage gearbox computer model that emulates an actual gearbox test rig. The computer model contains actual gearbox geometry, flexible shafts, bearings, gear contact forces, input motor torque, output brake torque, and realistic gearbox imbalance. The gear contact force of each gear stage and the input bearing translational acceleration were the main outputs compared between a healthy gearbox and damaged gearbox computer model. The damage of focus was a fatigue crack on the input pinion gear. A sideband energy …

Team Nathan Suspension, Frankie J. Wiggins, Alex D. Seitz, Justin P. Bautista

Mechanical Engineering

Nathan Cooper is an 8-year old boy with Spinal Muscular Atrophy (SMA). SMA has affected Nathan’s muscle development and requires him to use the Standing Dani™ mobility device. The Standing Dani is a motorized standing wheelchair, or Wheelstand. Nathan controls and uses it to get around. Though the Standing Dani performs well for most functions, it has some distinct issues. The primary issue that this project addresses is its lack of suspension and the discomfort that Nathan feels as a result. After talking with our client, we developed several specifications generally related to geometry, safety, vehicle dynamics, and reliability. Many …

Effects Of Thermal Boundary Conditions During Finite Element Modeling Of Physical Vapor Transport, Wade Luhman

Journal of Undergraduate Research at Minnesota State University, Mankato

Physical vapor transport (PVT) is a material processing method commonly used to produce different types of semiconductor materials. Computer modeling of PVT is important to understand the fundamentals of the processing method. Due to the large amount of computer processing power and storage needed to solve the computer models many of the previously solved simulations have been simplified to efficiently utilize computer usage. Previous PVT computer simulations of mercurous chloride (Hg2Cl2) have assumed constant temperature profiles on the source and crystal substrate for simplicity. These simulations were performed using the FIDAP computational fluid dynamics software package. In this research the …

Three Dimensional Transient Asymmetric Flowfields In Physical Vapor Transport, Joseph Dobmeier

Journal of Undergraduate Research at Minnesota State University, Mankato

Physical Vapor Transport is a manufacturing process used to produce single crystals of semiconductor materials such as mercurous chloride (Hg2Cl2). In the past this time-varying process has been studied with numerical simulation by considering three dimensional flow using an axi-symmetric two dimensional model or by restricting the simulation to asymmetric two dimensional flow and dropping the assumption of axi-symmetry from the model. It is generally agreed that neither of these methods accurately represent the true behavior of the process. The purpose of this research was to extend the asymmetric two dimensional model to three dimensions thereby obtaining a solution which …

Increased Span Length For The Mgs Long-Span Guardrail System, Nicholas A. Weiland

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

Long-span guardrail systems have been recognized as an effective means of shielding low-fill culverts while minimizing construction efforts and limiting culvert damage and repair. The current MGS long-span design provided the capability to span unsupported lengths up to 25 ft (7.6 m) without the use of nested guardrail. The excellent performance of the MGS long-span system in full-scale crash tests suggested that longer span lengths may be possible with the current design.

A detailed analysis of the MGS long-span guardrail system was performed using the finite element software program LS-DYNA^®. It was shown that the MGS long-span design …

Adapted Pool Cue, Cole Clark, Daniel Patterson, Michelle Cheung, Dylan Sauer

Mechanical Engineering

Our primary goal was to develop an adaptive device to allow a user with limited upper body mobility to more effectively play a game of pool. Within this goal it was important to design around the concept of a least restrictive environment, in order to provide the user with as close to a standard pool playing experience as possible. The device was designed to specifically meet the needs of John Lee, an Assistive Technology Specialist at Cal Poly's Disability Resource Center. Mr. Lee has muscular dystrophy, which limits his upper and lower body mobility and currently requires his use of …

St. Jude Medical - R&D Robot For Sensor Testing, Andrew Chanul Kim, Stanley Logan Laszczyk, Edgar Nava, Nathan Gall

Electrical Engineering

No abstract provided.

Formula Sae Hybrid Carbon Fiber Monocoque / Steel Tube Frame Chassis, Matthew Hagan, John Rappolt, John Waldrop

Mechanical Engineering

The Cal Poly Formula SAE Team created this project in order to design and fabricate a high-performance chassis which would be competitive at 2013 FSAE Lincoln, and to document the process so that future teams could more easily create a chassis. One of the main goals was to reduce weight from the 143- lb 2012 chassis subsystem. A weight of 95 lb was achieved, with 82 lb in the chassis structure itself and a predicted torsional stiffness of 1700 lb*ft/deg. Composite materials design and manufacturing techniques were developed during the project. Design, testing, and manufacturing processes are detailed, and results …

Friction Test Machine, Kyle Raymon Schless, Lynda Beatriz Tesillo, Mustapha Nadri

Mechanical Engineering

No abstract provided.

Development Of A Finite Element Model For Predicting The Impact Energy Absorbing Performance Of A Composite Structure, Matthew Lowell Roberts

Master's Theses

Because of their high strength-to-weight ratio, Fiber Reinforced Composite (FRC) materials are well suited for use in high performance racing applications where weight must be kept to a minimum. Formula SAE (FSAE) race cars are designed and built by college students, roughly following the model of a scaled down Formula One car. Strict regulations are placed on specific components of the car in the interest of equalizing competition and ensuring the safety of the drivers. Students are required to construct a survival cell (the chassis), which can resist large amounts of energy in the event of a crash, with an …

Process Capability In A Computer Integrated Manufacturing Cell, Andrew Austin

Masters Theses & Specialist Projects

With the rise of automation in traditional manufacturing processes, more companies are beginning to integrate computer integrated manufacturing (CIM) cells on their production floors. Through CIM cell integration, companies have the ability to reduce process time and increase production. One of the problems created with CIM cell automation is caused by the dependency the sequential steps have on one another. Dependency created by the previous step increases the probability that a process error could occur due to previous variation. One way to eliminate this dependency is through the use of an in-process measuring device such as a Renishaw spindle probe …

3d Printing Of Stainless Steel For Engineering Applications, Michael Doyle

Undergraduate Research Symposium

3-D metal printing has the potential to solve problems in the medical, prototyping, automotive, aerospace, defense, and other engineering industries. To reach the potential of any manufacturing process, the final product’s material characteristics and how the process affects those characteristics must be understood to meet the demands of industrial applications. There is a gap in standard testing information regarding metal based 3-D metal printing processes. The purpose of this research is to fill that gap of valuable information for this manufacturing process, so that its principles can be used to design better products. Fundamental tensile and compression tests were executed …

Using “Expert Employees” To Identify Duties And Tasks For Cadd Technicians In North Central Idaho: Lessons Learned From A Modified Dacum Process, Raymond A. Dixon Ph.D., Linda S. Stricklin Ph.D.

Online Journal for Workforce Education and Development

Objective: We conducted a job analysis to identify the competency profile of an entry level CADD technician in North central Idaho. Background: In 2011, the Clearwater Economic Development Association and NIMA collaborated with Lewis-Clark State College and the University of Idaho in a project to strengthen the capacity of Career and Technology Education (CTE) teachers to teach computer aided drafting and designing (CADD). An application to the National Science Foundation, Advanced Technology Education (NSF ATE) program was made and funding began July of 2011. Method: A modified DACUM was used. A total of seven expert workers from …

Reconciling Function- And Affordance-Based Design, Benjamin T. Ciavola

Dissertations, Master's Theses and Master's Reports - Open

Traditional engineering design methods are based on Simon's (1969) use of the concept function, and as such collectively suffer from both theoretical and practical shortcomings. Researchers in the field of affordance-based design have borrowed from ecological psychology in an attempt to address the blind spots of function-based design, developing alternative ontologies and design processes. This dissertation presents function and affordance theory as both compatible and complimentary. We first present a hybrid approach to design for technology change, followed by a reconciliation and integration of function and affordance ontologies for use in design. We explore the integration of a standard function-based …

Computational And Experimental Study On Vertical Axis Wind Turbine In Search For An Efficient Design, Mohammad M. Bashar

College of Graduate Studies: Theses & Dissertations

Wind alone can fulfill most of the energy requirement of the world by its efficient conversion in to energy. Though Horizontal Axis Wind Turbine (HAWT) is more popular but needs high wind speed to generate energy. On the other hand Vertical Axis Wind Turbine (VAWT) needs low wind speed and can be installed anywhere which are some of the reasons for this research. The main objective of this research is to improve the design and performance of VAWT to make it more attractive, efficient, durable and sustainable. For a VAWT the blades perform the main role to extract energy from …

A Design Pathfinder With Material Correlation Points For Inflatable Systems, Jared T. Fulcher

Theses and Dissertations--Mechanical and Aerospace Engineering

The incorporation of inflatable structures into aerospace systems can produce significant advantages in stowed volume to mechanical effectiveness and overall weight. Many applications of these ultra-lightweight systems are designed to precisely control internal or external surfaces, or both, to achieve desired performance. The modeling of these structures becomes complex due to the material nonlinearities inherent to the majority of construction materials used in inflatable structures. Furthermore, accurately modeling the response and behavior of the interfacing boundaries that are common to many inflatable systems will lead to better understanding of the entire class of structures. The research presented involved using nonlinear …

Numerical Analysis Of Droplet Formation And Transport Of A Highly Viscous Liquid, Peiding Wang

Theses and Dissertations--Mechanical and Aerospace Engineering

Drop-on-demand (DOD) inkjet print-head has a major share of the market due to simplicity and feasibility of miniature system. The efficiency of droplet generation from DOD print-head is a result of several factors, include viscosity, surface tension, nozzle size, density, driving waveform (wave shape, frequency, and amplitude), etc. Key roles in the formation and behavior of liquid jets and drops combine three dimensionless groups: Reynolds number, Weber number and Ohnesorge number. These dimensionless groups provide some bounds to the “printability” of the liquid. Adequate understanding of these parameters is essential to improve the quality of droplets and provide guidelines for …

Review Of Development Stages In The Conceptual Design Of An Electro Hydrostatic Actuator For Robotics, Velibor Karanović, Mitar Jocanović, Vukica Jovanović

Engineering Technology Faculty Publications

The design of modern robotic devices faces numerous requirements and limitations which are related to optimization and robustness. Consequently, these stringent requirements have caused improvements in many engineering areas and lead to development of new optimization methods which better handle new complex products designed for application in industrial robots. One of the newly developed methods used in industrial robotics is the concept of a self-contained power device, an Electro-Hydrostatic Actuator (EHA). EHA devices were designed with a central idea, to avoid the possible drawbacks which were present in other types of actuators that are currently used in robotic systems. This …

The Effects Of Layer Thickness On Dry-Sliding Wear Of Binder Jet Additively Manufactured Stainless Steel And Bronze Composite, Cody Ingenthron

All Graduate Theses, Dissertations, and Other Capstone Projects

Pin on disk wear testing was used to compare additively manufactured binder jet metal matrix composites. The process parameters were changed. The layer thickness and applied forces were varied for the experimental study. Three different layer thicknesses used were, 50μm, 100μm, and 200μm. The pin used was a 420 stainless pin. The wear characteristics of the disk were examined using pin-on-disc method. The material tested was a composite of 420 stainless steel, and 90-10 bronze. Samples were weighed before, during, and after the test to determine differences in mass. Wear tracks were examined using a Scanning Electron Microscope. The results …

A Comparative Analysis Of Spatial Visualization Ability And Drafting Models For Industrial And Technology Education Students, Petros Katsioloudis, Vukica Jovanović, Mildred Jones

Engineering Technology Faculty Publications

The article presents the comparative study on the drafting models and spatial visualization ability of industrial and technology education students in the U.S. It discusses how the study was conducted which examined the issue based on technical drawings and with regards to the impacts of model types. The results reportedly revealed three-dimensional models are effective for promoting learning, however more studies have to be conducted.

A Practical Tool For The Determination Of Surface Stresses In Railroad Bearings With Different Contact Geometries And Load Conditions Using Finite Element Analysis, Michael A. Mason

Theses and Dissertations

The connection between contact geometry and fatigue in tapered roller bearings utilized in the railroad environment is still of interest. Roller bearings for railroad applications are typically precision ground with crowned contact geometries to prevent edge loading of components. This normally results in completely elastic Hertzian contact stresses under standard railcar loads. However, under extreme load conditions, detrimental edge loading has been known to occur. It is proposed to develop a tool, using finite element analysis, that can be utilized to optimize complex raceway crown geometries for severe applications.

A successful implementation of this tool is presented and validated using …

Fault-Tolerant Trajectory Tracking Of Unmanned Aerial Vehicles Using Immunity-Based Model Reference Adaptive Control, Brenton K. Wilburn

Graduate Theses, Dissertations, and Problem Reports (ETD)

This dissertation presents the design, development, and simulation testing of an adaptive trajectory tracking algorithm capable of compensating for various aircraft subsystem failures and upset conditions. A comprehensive adaptive control framework, here within referred to as the immune model reference adaptive control (IMRAC) algorithm, is developed by synergistically merging core concepts from the biologically- inspired artificial immune system (AIS) paradigm with more traditional optimal and adaptive control techniques. In particular, a model reference adaptive control (MRAC) algorithm is enhanced with the detection and learning capabilities of a novel, artificial neural network augmented AIS scheme. With the given modifications, the MRAC …

Predicting Pressure Distribution Between Transfemoral Prosthetic Socket And Residual Limb Using Finite Element Analysis, Rajesh Surapureddy

UNF Graduate Theses and Dissertations

In this study, a non-linear Finite Element (FE) model was created and analyzed to determine the pressure distribution between the residual limb and the prosthetic socket of a transfemoral amputee. This analysis was performed in an attempt to develop a process allowing healthcare providers and engineers to simulate the fit and comfort of transfemoral prosthetics to reduce the number of re-fittings needed for the amputees. The analysis considered the effects of interference due to insertion of the limb into the prosthesis, referred to as donning, and also the effects due to the body weight of the amputee. A non-linear finite …