Mechanical Engineering Commons^™

Hybrid Nanomanufacturing Process For High-Rate Polymer Nanofiber Production, Chad T. Peterson

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

Nanotechnology and nanomaterials have the potential to revolutionize existing and create entirely new industries. Unique physical, mechanical, chemical, and biological properties of nanomaterials have been extensively documented in the last two decades. However, most nanomaterials are discontinuous in nature, creating problems with their processing and manipulation into devices and raising health concerns. Continuous nanofibers represent an emerging class of nanomaterials with critical advantages to applications. Continuous nanofibers are readily produced by electrospinning process comprising spinning polymer solutions in high electric fields. Electrospinning is a very economic top-down nanomanufacturing process that has been used to produce ultrafine continuous nanofibers from several …

Robot Crawling Device And Tee Table, Todd P. Trauman, Kyle M. Colvin, David Charles Fantz

Mechanical Engineering

As golf becomes a more frequently enjoyed activity, equipment manufacturers such as Hot Stix Golf require updated testing mechanisms to actively compete in their respective markets. One such testing device is a golfing robot nicknamed the “Iron Byron”. Two issues were asked to be addressed for the senior project. First, the robot was practically immobile unless taken apart and moved with a forklift. The request from Hot Stix was to mobilize the robot so that it could easily be transported with minimal use of external help. Secondly, the initial tee-table was both poorly-designed and missing altogether. The new tee-table needed …

Water Well Drilling Rig Final Project Report, Alexander (Alex) Wargnier, Thad Jablonski, Coel Schumacher

Mechanical Engineering

In this report, the improvements of a previously produced cable tool drilling rig are described. The purpose of the rig is to drill water wells for use in Africa in order to provide safe drinking water to many in need. An affordable, effective, and controllable rig is the design goal for this project. With the San Luis Obispo Rotary Club sponsoring the project the design team of WHole Engineering have made necessary design choices to manufacture the product. Actions performed include background research of existing drilling technologies, analysis of top concepts for the controlling mechanism, and selection for the final …

The Quadricycle Hand And Foot Cycle, Marissa Chin, Parker Drennan, Spencer Nelson, Kevin Reidy

Mechanical Engineering

This report documents the design process from concept generation to manufacturing for a hand and foot powered cycle named the Quadricycle.  The Quadricycle project is a joint effort at California Polytechnic State University in San Luis Obispo between the Mechanical Engineering and Kinesiology Departments.  The project objectives are to design a portable cycle that can be powered by hands and feet simultaneously in order to provide recreation and rehabilitation for a person with a disability.  This project is funded under a grant by the National Science Foundation (NSF).

2-D Path Planning For Direct Laser Deposition Process, Swathi Routhu, Divya Kanakanala, Jianzhong Ruan, Xiaoqing Frank Liu, Frank Liou

Computer Science Faculty Research & Creative Works

The zigzag and offset path have been the two most popular path patterns for tool movement in machining process. Different from the traditional machining processes, the quality of parts produced by the metal deposition process is much more dependent upon the choice of deposition paths. Due to the nature of the metal deposition processes, various tool path patterns not only change the efficiency but also affect the deposition height, a critical quality for metal deposition process. This paper presents the research conducted on calculating zigzag pattern to improve efficiency by minimizing the idle path. the deposition height is highly dependent …

Axisymmetric Finite Element Modeling For The Design And Analysis Of Cylindrical Adhesive Joints Based On Dimensional Stability, Paul E. Lyon

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The use and implementation of adhesive joints for space structures is necessary for incorporating fiber-reinforced composite materials. Correct modeling and design of cylindrical adhesive joints can increase the dimensional stability of space structures. The few analytical models for cylindrical adhesive joints do not fully describe the displacement or stress field of the joint.

A two-dimensional axisymmetric finite element model for the design and analysis of adhesive joints was developed. The model was developed solely for the analysis of cylindrical adhesive joints, but the energy techniques used to develop the model can be applied to other types of joints as well. …

Me-Em Enewsbrief, December 2010, Department Of Mechanical Engineering-Engineering Mechanics, Michigan Technological University

Department of Mechanical and Aerospace Engineering eNewsBrief

No abstract provided.

The Effects Of Roof Solar Absorptance On Building Energy Performance In A Variety Of U.S. Climate Zones, Zachary Eubanks

Mechanical Engineering Undergraduate Honors Theses

The solar absorptance of a roof surface directly affects the solar heat gain through the roof. It has been shown that buildings in hot climates benefit from roofs with low absorptance. Cold and moderate climates have received less attention in previous studies. This paper simulates the effects on annual energy use, carbon dioxide emission, and utility cost of varying the solar absorptance of warehouse and small office building roofs in a wide variety of U.S. climate zones using EnergyPlus software and the DOE Commercial Building Benchmark Models. Results show that the optimum absorptance not only depends on the climate zone, …

Design And Implementation Of An Actively Adjustable Spring Mechanism Via Redundant Actuation, Eleazar Marquez

Theses and Dissertations - UTB/UTPA

This study presents the theoretical results and experimental validation of an adjustable stiffness mechanism. The use of redundant actuation is emphasized in the design of a one-degree-of-freedom Watt II mechanism capable of independently controlling the effective stiffness without a change in equilibrium position. This approach is in contrast to previous spring mechanism designs unable to actively control the spring rate independent of deflection, and has potential applications in various types of suspension and assembly systems. Results indicate that driving the redundantly actuated, unidirectional, spring mechanism requires attaching two direct brush-type direct current motors on each of the two grounded revolute …

A Study Of The Effect Of Vibration On Railroad Bearing Temperature, Bertha Alicia Gonzalez

Theses and Dissertations - UTB/UTPA

An on-track collaborative field test and laboratory experiments were conducted in order to determine the relationship between abrupt rises in surface temperature of a railroad bearing and vibration signatures captured during the experiments. The collaborative field test was conducted in order to investigate the root cause for this abrupt temperature change known as bearing temperature trending. The research presented in this thesis will show that temperature trending is correlated to an increase in the magnitude of vibration within the bearing and the fundamental frequencies that are generated by the internal components of a rotating bearing assembly. Distinct vibration mechanisms are …

Photonic Crystal Design And Fabrication Assisted By Tunable Femtosecond Oscillator Laser, Kristofer B. Ohlinger

Theses and Dissertations - UTB/UTPA

Photonic Crystals have the potential for engineered light interaction as directed by the photonic bandgap, a property that details the prohibited propagation region and ultimately the ability to guide light. A so called, photonics-on-chip, would incorporate arbitrary light guiding with functional elements in one package. The realization of such a device is subject to the fabrication paradigms implemented and this thesis is concerned with holographic lithography as a means for creating polymer photonics crystal templates and two-photon polymerization for incorporating light guiding pathways.

In this thesis, the design of the to-be-fabricated structures has been co-opted by computational exploration of the …

Computational Analysis For Improved Design Of An Sae Baja Frame Structure, Nagurbabu Noorbhasha

UNLV Theses, Dissertations, Professional Papers, and Capstones

Baja SAE is an intercollegiate competition to design, fabricate, and race a small, single passenger, off-road vehicle powered by a 10 HP Briggs & Stratton 4-Stroke gasoline engine. All Baja SAE vehicles for the competition are powered by a small engine, thus large part of vehicle performance depends on the acceleration and maneuverability of the vehicle which is proportional to the weight of the chassis and rollcage. As weight is critical to achieve the greater performance of the vehicle, a balance must be found between the strength and weight of the rollcage to ensure the safety of the driver.

The …

College Of Engineering Senior Design Competition Fall 2010, University Of Nevada, Las Vegas

Fred and Harriet Cox Senior Design Competition Projects

Part of every UNLV engineering student’s academic experience, the senior design project stimulates engineering innovation and entrepreneurship. Each student in their senior year chooses, plans, designs, and prototypes a product in this required element of the curriculum. A capstone to the student’s educational career, the senior design project encourages the student to use everything learned in the engineering program to create a practical, real world solution to an engineering challenge.

The senior design competition helps to focus the senior students in increasing the quality and potential for commercial application for their design projects. Judges from local industry evaluate the projects …

Mobility Aid: A Dual Purpose Walker And Scooter, Zack Blois, Robia Choi, Kristin Dills

Mechanical Engineering

The Mobility Aid project was proposed by Theresa Mortilla and Idee Shapiro. The goal of the project was to design and build a device that can quickly and easily transform between a mobility walker and an electric scooter to allow for more freedom of mobility. The inspiration for this project arose from the fact that Theresa suffers from multiple sclerosis in her legs and can only walk for about thirty minutes at a time until she gets too fatigued and must sit down and rest. This device would provide her with the ability to continue moving while giving her legs …

Foam Wars Ii, Sumant Advani, Sivadas Menon, Casey Pieplow

Mechanical Engineering

The team producing Foam Wars II consists of three Mechanical Engineering students and five Kinesiology students (three the first two quarters and two the last quarter) at California Polytechnic State University, San Luis Obispo. The project is the second iteration of Foam Wars as a senior project at Cal Poly, sponsored by Dr. Kevin Taylor under the National Science Foundation grant. Persons with disabilities often feel limited when it comes to recreational activities and Foam Wars would provide them with an outlet to interact and engage themselves in a group setting. The game consists of various wheelchair attachments that would …

Universal Play Frame Vi, Justin Bazant, Cullen Crackel, Anthony Franceschi

Mechanical Engineering

This design report details the design process utilized by Adaptive Exercise Designs (AED) in creating the sixth design of the Universal Play Frame (UPF). The UPF is an adaptive frame which supports a variety of devices that allows athletes in wheelchairs with limited range of motion to participate in physical activity. The past five frame designs do not meet the needs of the Friday Club due to complications with function and time constraints. To ensure all of Fridays Club's needs were met, the problem was better defined by converting the customer requirements into engineering specifications. The design process our team …

Piedras Blancas Clock Works, Andrew James, Andrew Jupin, Matt Weber

Mechanical Engineering

In 1875, the Piedras Blancas Lighthouse was built to warn ships sailing the California coast of the hazards of the rocky shore. In 1949 a fierce storm damaged the top portion of the lighthouse and the eight ton cast iron and brass assembly had to be replaced by a much lighter piece that still served the purpose of warning oncoming vessels. The former top portion came to rest in downtown Cambria and is still there today, enclosed in a glass room to be observed by visitors and townspeople. Today, the Piedras Blancas Light station is cared for by the Bureau …

Experimental And Computational Analysis Of An Energy Storage Composite Ankle Foot Orthosis, Michelle C. Hawkins

UNLV Theses, Dissertations, Professional Papers, and Capstones

Ankle Foot Orthotics (AFOs) are used by individuals presenting with Charcot-Marie-Tooth (CMT) to assist with improving gait. Mitch Warner, CPO, has developed a composite AFO made from woven carbon-Kevlar and carbon fiber lamina. The overall goals of the research are to characterize the HELIOS brace and to determine its effect on the gait of CMT subjects. Human motion analysis, experimental mechanical testing, and Finite Element Analysis (FEA) are used to gain a better understanding of how the materials and geometric design of the HELIOS AFO contribute to gait.

Human motion experiments are performed to determine the relationship between ground reaction …

A Computational Method For Analysis Of Material Properties Of A Non-Pneumatic Tire And Their Effects On Static Load Deflection, Vibration And Energy Loss From Impact Rolling Over Obstacles, Akshay Narasimhan

All Theses

One of the potential sources of vibration during rolling of a non pneumatic tire is the buckling phenomenon and snapping back of the spokes in tension when they enter and exit the contact zone. Another source of noise was hypothesized due to a flower pedal ring vibration effect due to discrete spoke interaction with the ring and contact with the ground during rolling as the spokes cycle between tension and compression. Transmission of vibration between the ground force, ring and spokes to the hub was also considered to be a significant contributor to vibration and noise characteristics of the Tweel. …

A Computational Investigation Of Contact Pressure For A Non-Pnemautic Wheel With A Meta-Material Shear Band, Renuka Jagadish

All Theses

One of the missions of National Aeronautics Space Administration (NASA) is to develop a vehicle that can travel for a longer distance on the moon and have a greater degree of mobility compared to the currently used Lunar Roving Vehicles (LRV). This led to the development of the All-Terrain Hex-Limed Extra-Terrestrial Explorer (ATHLETE), which requires a significant advance in the type of wheels that must be used on this highly mobile lander. The Michelin Lunar Wheel, which is a non-pneumatic tire invented by Michelin Researche et Technologie has been identified as one of the key designs capable of performing on …

Advanced Automotive Thermal Management - Operation Of An Electric Radiator Fan Array For Reduced Electric Power Consumption, Amit Jagarwal

All Theses

The depletion of fossil fuel reserves and the limited renewable energy resources have raised public awareness about the need to improve fuel efficiency in ground transportation vehicles. The internal combustion engine remains one of the primary industrial machines using gasoline or diesel fuel to produce mechanical work. In these engines, the cooling system performs the vital role of removing waste heat to ensure normal combustion processes in the cylinders. To accomplish this task, the radiator, the radiator fan(s), the thermostat valve, and the water pump operated by circulating cooling fluid through the engine block and rejecting heat to the atmosphere. …

Incorporating Function Structures Into Morphological Charts: A User Study, Jenkins Richardson Iii

All Theses

A morphological chart is an ideation tool that represents a large qualitative design space. Currently, morphological charts use a function list to as the function representation of the design problem. Using the morphological chart means (solutions) that can perform each function are generated. Combining one means from each function produces an integrated conceptual design solution. By repeating this process with all possible combination contained in the morphological chart, a long list of conceptual design solutions will be generated, although not all will be practical. This long list of potential design solutions is difficult to analyze and there are limited systematic …

Mass And Assembly Time Reduction For Future Generation Automotive Vehicles Based On Existing Vehicle Model, Essam Namouz

All Theses

This research presents method for evaluating the lightweightedness of a vehicle and an approach for vehicle assembly time savings potential developed through a case study. The Lazy Part Identification method for mass reduction specifically addresses those components whose primary purpose is to aid in manufacturing and assembly rather than to provide end-user function. Seven specific laziness indicators are described and illustrated: rigid-to-rigid connection, support for a flexible, non-moving part, positioning feature, duplicate geometry, fastener, bridging system, and material flow restriction. These indicators are used to evaluate individual vehicle components as part of a proposed method for identifying mass reduction potential. …

Analysis Of Alternative Manufacturing Processes For Lightweight Biw Designs, Using Analytical Hierarchy Process, Srinath Vijayakumar

All Theses

The main objective of the analysis was to investigate the forming of Body in White (BIW) panels using alternative processes most suitable for replacing the conventional press working process in order to achieve a reduction in the total mass of the vehicle body structure. The selection of the alternatives was guided by multi criteria decision making tool, the Analytic Hierarchy Process (AHP). Here the alternatives were selected based on their relative importance to the different manufacturing attributes considered. The selected processes were applied to the manufacturing of different parts of BIW indicated in the BOM along with suggestion of the …

Pulsed-Laser Direct Writing Of Biological Materials, Yafu Lin

All Dissertations

Laser direct writing, developed based on modified laser-induced forward transfer (LIFT), has been emerging as one of the most promising biofabrication techniques. While some studies have been conducted to investigate laser direct writing of biological materials, there are some key challenges such as mechanisms of bubble formation, droplet formation and process-induced cell injury that have not been well elucidated. The objective of this dissertation is to study laser-induced droplet formation dynamics and process-induced cell injury in pulsed-laser direct writing of biological materials, and improve the existing laser direct-write techniques.
Phase explosion is identified as the dominant bubble formation mechanism in …

Predictive Energy Management In Connected Vehicles: Utilizing Route Information Preview For Energy Saving, Chen Zhang

All Dissertations

This dissertation formulates algorithms that use preview information of road terrain and traffic flow for reducing energy use and emissions of modern vehicles with conventional or hybrid powertrains. Energy crisis, long term energy deficit, and more restrictive environmental protection policies require developing more efficient and cleaner vehicle powertrain systems. An alternative to making advanced technology engines or electrifying the vehicle powertrain is utilizing ambient terrain and traffic information in the energy management of vehicles, a topic which has not been emphasized in the past. Today's advances in vehicular telematics and advances in GIS (Geographic Information System), GPS (Global Positioning Systems), …

A Study Of The Statistics Of The Air/Water Interfacial Temperature Field During Mixed Convection Heat Transfer, Jie Kou

All Dissertations

Heat transfer across an air/water interface is of particular importance to limnology, oceanography and some industrial applications. The relationship between the statistics of the air/water interfacial temperature field and the interfacial heat flux is poorly understood, particularly for the mixed convection condition, which is a common heat transfer mechanism for small inland lakes. The few studies that have been conducted under mixed convection conditions have been limited to an uncontrolled surfactant condition (tap water). Therefore, in this dissertation research two sets of experiments for wind speeds from 0 to 4 m/s were conducted: controlled surfactant contaminated conditions (with oleyl alcohol) …

Tidal Current Energy Resource Assessment In Ireland: Current Status And Future Update, Fergal O'Rourke, Fergal Boyle, Anthony Reynolds

Articles

Interest in renewable energy in Ireland has increased continually over the past decade. This interest is due primarily to security of supply issues and the effects of climate change. Ireland imports over 90% of its primary energy consumption, mostly in the form of fossil fuels. The exploitation of Ireland’s vast indigenous renewable energy resources is required in order to reduce this over dependence on fossil fuel imports to meet energy demand. Various targets have been set by the Irish government to incorporate renewable energy technologies into Ireland’s energy market. As a result of these targets, the development in wind energy …

Improved Mobile Wireless In Vivo Surgical Robots: Modular Design, Experimental Results, And Analysis, Jeff Hawks

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

Laparoscopic surgery results in superior patient outcomes as measured by less painful recovery and an earlier return to functional health compared to conventional open surgery. However, the difficulty of manipulating laparoscopic tools from outside the patient’s body generally limits these benefits to patients undergoing relatively simple procedures. The use of miniature in vivo robots that fit entirely inside the peritoneal cavity represents a novel approach to laparoscopic surgery. These robots enable more complex laparoscopic procedures, increasing the number of patients that benefit from laparoscopic surgery.

This thesis describes recent work focused on developing a modular wireless mobile platform that can …

Artificial Skin Tactile Sensor For Prosthetic And Robotic Applications, Ross James Miller

Master's Theses

To solve the problem of limited tactile sensing in humanoid robotics as well as provide for future planned mechanical prostheses, an innovative tactile sensor system was created and embedded into two realistic-looking artificial skin gloves. These artificial skin tactile sensors used small piezoelectric ceramic disks to measure applied force at multiple points on each glove. The gloves were created using silicone rubber to simulate both the texture and look of human skin, while maintaining both flexibility and durability. The sensor outputs were buffered by high-impedance voltage-following operational amplifiers, and then read sequentially using a multiplexing scheme by a microcontroller. Sensor …