Simulation, Control And Testing Of A Custom 5-Dof Robotic Manipulator System,
2018
University of Texas at Arlington
Simulation, Control And Testing Of A Custom 5-Dof Robotic Manipulator System, Roopak M. Karulkar
Mechanical and Aerospace Engineering Theses - Archive
Open chain manipulators are a well posed problem, however it was necessary to build a system customized to meet the needs of the Unmanned Ground Vehicle developed in the Aerospace Systems Laboratory. Considering that there are multiple such small ground vehicles, the main design constraint on the system was to be modular and lightwieght to enable quick swapping from both, a hardware and a software point of view. The purpose of this thesis is design, simulation and control a modular 5-Degree-of-Freedom manipulator with versatility in end effector configuration. This was achieved through the Robot Operating System which brings a high …
Experimental Investigation Of Thermophysical Properties Of Enhanced Nitrate Salt Nanofluids For Thermal Energy Storage (Tes) In Concentrated Solar Power (Csp) Systems,
2018
University of Texas at Arlington
Experimental Investigation Of Thermophysical Properties Of Enhanced Nitrate Salt Nanofluids For Thermal Energy Storage (Tes) In Concentrated Solar Power (Csp) Systems, Vamsi Kiran Eruvaram
Mechanical and Aerospace Engineering Theses - Archive
The main source for energy production right now is from thermal, nuclear energy. But in the near future we might have crisis of coal so we need alternate renewable source for energy production the solution for that is sun, since solar energy is renewable and abundantly available. Concentrated solar power (CSP) technologies is one of the best solution to overcome this energy crisis, because it works from solar energy. If the CSP is incorporated with thermal energy storage (TES) we can produce energy even during night. TES with 15-hour storage capacity (Gemasolar) is already commercialized to operate a CSP plant …
Additive Manufacturing Process Investigation For The Fabrication Of Composite Scaffolds For Soft Tissue Application,
2018
University of Texas at Arlington
Additive Manufacturing Process Investigation For The Fabrication Of Composite Scaffolds For Soft Tissue Application, Parimal Patel
Mechanical and Aerospace Engineering Theses - Archive
Additive manufacturing has been investigated and employed in the bio-medical domain for the fabrication of various devices and scaffolds. In various soft tissue engineering applications, multi-functional multi-material scaffolds are required for cell proliferation, structural integrity, bio-compatibility and tissue regeneration. In this research, an additive manufacturing methodology is developed to allow the fabrication of bio-composite scaffolds using a multi-modality in-house built platform. The researched materials for printing are Poly-L-Lactic Acid (PLLA) and a newly developed photo-curable radiopaque polymer called Rylar (Poly glycerole sebacate fumarate gadodiamide) mixed with a cross-linking agent Poly (Ethylene glycol) diacrylate (PEGDA). The developed methodology uses a Fused …
Reliability Of A 2.5d Tsv Package,
2018
University of Texas at Arlington
Reliability Of A 2.5d Tsv Package, Neha Vinayak Gaikwad
Mechanical and Aerospace Engineering Theses - Archive
In the recent years, the Through Silicon Vias (TSVs) are helping a huge variety of the 3D IC and the 2.5D IC packaging applications to try to fulfill their requirements of functionality and higher connectivity at the expense of lower power consumption and minimum heat dissipation. The TSVs offer great interconnect density, high device density, short connection paths, great space efficiency and high interconnect bandwidth. The basic difference between a 3D TSV package and a 2.5D TSV package is that the 2.5D one interconnects the dies side by side on a silicon interposer, over its entire length. The interposer, placed …
Mass Fabrication & Evolution Of Beads On Fiber,
2018
University of Texas at Arlington
Mass Fabrication & Evolution Of Beads On Fiber, Kirthika Suresh
Mechanical and Aerospace Engineering Theses - Archive
In this work, we systematically explore the relation between the coating speeds and the finally formed liquid beads on fiber. The main focus of the paper lies with contact angle, length and height of beads on fiber and the fiber drawing velocity. For this purpose, free energy variation method is applied, based upon which the boundary conditions for the beads-on-fiber system and governing equations were re-derived. A combination of both, first and the second kind of the Legendre’s elliptical functions are used to determine the geometrical shape of the beads. Contact angle is extracted from the experimental data by using …
Predicting Mechanical Behavior Of 3d Printed Structures Using Mechanics Of Composites And Fracture,
2018
University of Texas at Arlington
Predicting Mechanical Behavior Of 3d Printed Structures Using Mechanics Of Composites And Fracture, Megha Tangri
Mechanical and Aerospace Engineering Theses - Archive
Recently, additive manufacturing, or 3D printing as it is more commonly called, has taken a big leap in the manufacturing industry. This technology is rapidly moving from prototyping to manufacturing using metals, polymers, concrete and even composites. Unlike subtractive methods of manufacturing, additive manufacturing can be used to manufacture parts with highly directional mechanical properties. This research focuses on predicting tensile failure of 3D printed polymer structures in different raster orientations using composites lamination theory. Previously it was found experimentally that tensile strengths of 3D printed specimens decrease when raster orientations changes from 0° to 90°. The proposed model developed …
Numerical Simulation Of Unsteady Normal Detonation Combustion,
2018
University of Texas at Arlington
Numerical Simulation Of Unsteady Normal Detonation Combustion, Ajjay Omprakas
Mechanical and Aerospace Engineering Theses - Archive
The objective of this research is to simulate normal detonation combustion which is a mode of operation for a Pulsed Detonation Engine (PDE). A supersonic flow with stoichiometric hydrogen-air mixture is made to impinge on a wedge, thus resulting in increasing the temperature and pressure across a shock wave leading to the formation of detonation wave. Different modes of the operations can be simulated by varying the incoming Mach number, pressure, temperature and equivalence ratio. For the case of normal detonation wave mode which is an unsteady process, after the detonation being initiated due to the shock induced by the …
Experimental And Analytical Study Of A Self-Regulated Flow Control Device Developed For Dynamic Cold-Plates To Cool High-Power Density Multi-Chip Modules,
2018
University of Texas at Arlington
Experimental And Analytical Study Of A Self-Regulated Flow Control Device Developed For Dynamic Cold-Plates To Cool High-Power Density Multi-Chip Modules, Rishi Ruben Palanikumar
Mechanical and Aerospace Engineering Theses - Archive
Modern high-power density modules often demand high amounts of power be invested in their cooling processes. Uneven heating at the chip level creates hotspots and temperature gradients across the module. A very effective way to conserve pumping power and address hotspots on the module is by targeted delivery of liquid coolant. One way to enable such targeted delivery of coolant is by using dynamic cold-plates (DCP) coupled with self-regulated flow control devices. This paper deals with the optimization and characterization of one such flow control device (FCD). The self-regulated FCD is actuated by a heat reactive shape memory alloy, Nitinol. …
Comparison Of Nonlinear Filters For An Autonomous Lunar Mission Using Existing Navigation Techniques,
2018
University of Texas at Arlington
Comparison Of Nonlinear Filters For An Autonomous Lunar Mission Using Existing Navigation Techniques, Matthew David Shaver
Mechanical and Aerospace Engineering Theses - Archive
Navigation systems play an important role for autonomous spacecraft. Earth based navigation systems such as GPS provide accurate positioning for orbiting spacecraft. In the case of lunar orbit, GPS is not available so other navigation techniques have to be used. This thesis proposes a novel idea to use Laser Ranging Retroreflectors, placed on the Moon's surface during the Apollo program, as a means of providing position information to an orbiting autonomous spacecraft. An Inertial Navigation System consisting of fusion of LRRR position data and Inertial Measurement Unit providing gyro and accelerometer data will be utilized during orbit about the Moon. …
Impact Of Thermal Aging On Crack Growth Behavior Of Lead Free Solder Interconnects,
2018
University of Texas at Arlington
Impact Of Thermal Aging On Crack Growth Behavior Of Lead Free Solder Interconnects, Anuraag Girish Karnik
Mechanical and Aerospace Engineering Theses - Archive
Reliability assessment helps in better performance of electronic packages. This also helps electronic device manufacturing company as well as the users to evaluate the life of any device. The microstructure, mechanical response, and failure behavior of Pb-free solder joints in electronic assemblies are constantly evolving when exposed to isothermal aging and/or thermal cycling environments. Due to reflow process or exposure to harsh environment conditions, packages are subject to fatigue loads which can accelerate crack growth in the solder interconnects. But, some material after aging get hardened and decrease in plastic deformation capacity. This effect sometimes leads to better crack resistance …
Finite Element Analysis Of Composite Reactor Pressure Vessel,
2018
University of Texas at Arlington
Finite Element Analysis Of Composite Reactor Pressure Vessel, Tejas Vasant Mhetre
Mechanical and Aerospace Engineering Theses - Archive
Reactor Pressure Vessel is the container designed to hold gases or liquids above atmospheric pressure. The focus of this study is to develop Finite Element Model to predict the performance of composite reactor pressure vessel subjected to extreme pressure and temperature and compare with pressure vessel manufactured using conventional materials. In the first part of the study, a pressure vessel system with Carbon steel material under design pressure and temperature have been analyzed for stresses, deformation and Safety Factor. Various loading cases have been discussed during the analysis of pressure vessel. Composite materials have been a suitable replacement to the …
Development And Validation Of The Deliquescent Relative Humidity Test Method For The Accumulated Particulate Matter Found In A Data Center Utilizing An Airside Economizer,
2018
University of Texas at Arlington
Development And Validation Of The Deliquescent Relative Humidity Test Method For The Accumulated Particulate Matter Found In A Data Center Utilizing An Airside Economizer, Roshan Anand
Mechanical and Aerospace Engineering Theses - Archive
Data centers are virtual or physical infrastructure utilized by enterprises to house computer, server and networking systems and other vital components for the needs of the company’s information technology mainly serving the purpose of storing, processing and serving large amounts of mission critical data to clients. As data centers house a network’s most critical systems and are extremely vital for the continuity of daily operations, every organization prioritizes the reliability and security of data centers and their information. A remarkable amount of data center energy is consumed in eliminating the heat generated by Information Technology (IT) equipment to maintain and …
Accelerated Thermal Cycling Of Printed Circuit Board For Single Phase Immersion Cooling Systems,
2018
University of Texas at Arlington
Accelerated Thermal Cycling Of Printed Circuit Board For Single Phase Immersion Cooling Systems, Surya Duraisamy Asokan
Mechanical and Aerospace Engineering Theses - Archive
The adoption of immersion cooling of data center over conventional air-cooling is one among the more up to date advances that individuals have begun embracing to. Acknowledgement of Single phase Liquid Immersion cooling (Sp-LIC) of Information Technology equipment gives proficient cooling frameworks and significant vitality energy savings. This study centers on the unwavering reliability assessment in analyzing the material property of Printed Circuit Board (PCB) and performing Scanning Electron Microscope (SEM) scanning of the samples for any penetration of liquids into PCB. The Accelerated Thermal Cycling (ATC) test in view of ATC JEDEC is relevant just for air cooling. The …
Human Robot Interaction With Cloud Assisted Voice Control And Vision System,
2018
University of Texas at Arlington
Human Robot Interaction With Cloud Assisted Voice Control And Vision System, Ravi Patel
Mechanical and Aerospace Engineering Theses - Archive
The objective of this research is to investigate a way of interaction between humans and robots, which is through voice or speech commands. A Biomimetic Artificial Hand (BAH) is used as a platform to perform grasping tasks using human voice as an interacting and instructing medium between humans and robots. It is a hands-free approach of issuing commands to the BAH since it does not require the user to wear any specialized equipment. Previous research has shown difficulties in recognizing more than one word, database management for stored voice, and requirement of sufficient computing power. National Instruments software LabVIEW and …
Solder Joint Design Optimization Of Quad-Flat Package With Gullwing Leads Under Accelerated Thermal Cycling And Power Cycling,
2018
University of Texas at Arlington
Solder Joint Design Optimization Of Quad-Flat Package With Gullwing Leads Under Accelerated Thermal Cycling And Power Cycling, Pranav Nikam
Mechanical and Aerospace Engineering Theses - Archive
Ever growing complexity in designing of Integrated Circuits and accommodating high number of Interconnections in the device is the main source of motivation in today’s world of IC devices. Quad Flat Package (QFP) with Gullwing leads is spearhead technology which enables high connectivity levels required to be customized in most convenient and advantageous form. Gullwing leads have the advantage of having a large area in contact with solder and also work as mechanical springs. They also make it easier to inspect and rework. Lot of work has been carried out on inspecting the reliability of solder joints in QFP packages …
Experimental And Numerical Investigation Of Heat Transfer In Battery Pack Of A Hoverboard,
2018
University of Texas at Arlington
Experimental And Numerical Investigation Of Heat Transfer In Battery Pack Of A Hoverboard, Abhinav Prasad
Mechanical and Aerospace Engineering Theses - Archive
Li-ion cells are used for energy storage and conversion in electric vehicles and a variety of consumer devices such as hoverboards. Performance and safety of such devices is severely affected by overheating of Li-ion cells in aggressive operating conditions. Several accidents due to fire in the battery pack of a hoverboard have been reported in the recent past. Despite the large number of hoverboards in use worldwide, there is a lack of systematic research on heat transfer in battery packs of hoverboards. This study presents experimental and numerical analysis of heat transfer in Li-ion battery pack of a hoverboard to …
Study Of The Effect Of Humidity On Thermal Cycling Of A Ball Grid Array (Bga) Package,
2018
University of Texas at Arlington
Study Of The Effect Of Humidity On Thermal Cycling Of A Ball Grid Array (Bga) Package, Samuel Terrence Ambosta
Mechanical and Aerospace Engineering Theses - Archive
Thermal Cycling (TC) Test is one of the most important reliability tests in the packaging and semiconductor industry. Humidity on the other hand is one of the significant factors for the reliability of packages, since there are several failures due to moisture absorption in packages. Humidity in packages can lead to soften them and decrease adhesive strength resulting into delamination near the solder tip and wire bond joint, which results in poor electric performance as well as reduced mechanical reliability. In addition, decrease in adhesive strength also causes corrosion in that area which leads to package failure. Absorption of humidity …
Comparison Of Steel And Composite Rail Axle By Finite Element Analysis,
2018
University of Texas at Arlington
Comparison Of Steel And Composite Rail Axle By Finite Element Analysis, Samip Nikulbhai Shah
Mechanical and Aerospace Engineering Theses - Archive
Axles are one of the most important railway vehicle parts that supports the weight of both vehicle and passenger. Failure in Axle in its operating condition may cause heavy damage to the passenger and car as well, hence high strength design is required to mitigate the possibilities of axle failure. Generally steel axle is used in rail industry, nowadays there are more interest to replace steel axle to the composite axle. Use of advanced composite material such as Kevlar, graphite-fiber, carbon-fiber and glass-fiber with proper resin core resulted in remarkable achievements because of its specific strength and improve fatigue, specific …
Trust Based Time-Varying Network Topology For Distributed Co-Operative Control Of Multi-Class Multi-Agent Systems,
2018
University of Texas at Arlington
Trust Based Time-Varying Network Topology For Distributed Co-Operative Control Of Multi-Class Multi-Agent Systems, Ankur Vipulkumar Dalal
Mechanical and Aerospace Engineering Theses - Archive
With increased levels of autonomy in most of the engineering fields and booms in areas such as swarms, platoons and Internet of Things (IoT), communication and information flow has become a highly researched field. With advancements in autonomous vehicles (AVs) and drones in armed warfare, more and more focus is being laid on intercommunication between these vehicles and its surroundings as well as intra-communication among the fleets/swarms itself. It is easier to deal with individual agents whereas it is quite challenging to deal with multi-agent systems especially with highly dynamic agents. In this thesis, we propose a general protocol for …
Dynamics And Control Of Jumping Legged Robot,
2018
University of Texas at Arlington
Dynamics And Control Of Jumping Legged Robot, Gurashish Singh
Mechanical and Aerospace Engineering Theses - Archive
This research aims to studying the agility of legged robots particularly their interactions with the ground and achieve a jumping motion by using an operational space controller. Methods were developed to first formulate the equations of motions of the full system. Then we used the published impact and contact analytical framework to detect simultaneous, indeterminate impact and transition to contact with friction and addressed the well-known issues with energy consistency when using rigid body models for dynamic systems (i.e. there are no unusual gains in the energy after impact has ended). Non-penetration of the ground was achieved through online constraint …
