Mechanical Engineering Commons^™

Prompt-Driven Tabletop Robotic Manipulation With A Structured Llm Interface And Visual Verification, Tomas Franco

Master's Theses

Creating a tabletop robotic manipulation system that connects language goals to robot actions is a challenging problem. Large language models can interpret mission objectives and reason through actions, but when placed directly in control of hardware they can produce hallucinated commands that result in unsafe behavior without the proper safeguards.

This thesis presents a constrained LLM-guided manipulation system built around the Quanser Qarm, a four degree of freedom manipulator with a mounted Realsense RGB-D camera and a gripper with readable current. Every decision made by the LLM planner is routed through a gated command interface that restricts the model to …

Extended Adaptive Oscillator Framework For Gait Phase Estimation With Adaptive Coupling And Transition Detection Across Locomotion Tasks, Nikhila Radha Krishnan

All Theses

Gait phase is a human-inspired physical variable that describes the instantaneous position of a person within a gait cycle. Adaptive oscillators have been widely used for gait phase estimation due to their ability to synchronize with periodic and pseudo-periodic biomechanical signals and generate monotonically increasing cyclic phase values. Typically, the performance of adaptive oscillators is strongly influenced by coupling strength, a parameter that bridges a trade-off between convergence speed and steady-state variability of the estimated stride frequency. In gait assistive applications, stride frequency estimation must be sufficiently fast to enable phase-based assistance while achieving a stable stride frequency estimate. The …

Smart Process Planning For Automated Fiber Placement, Matthew J. Godbold

All Dissertations

Automated Fiber Placement (AFP) is a preeminent manufacturing technology for producing high-performance composite structures, offering precise material placement, reduced waste, and the potential for highly optimized lightweight designs. While AFP has been widely adopted in aerospace applications, its broader use across industries such as automotive, wind energy, maritime, and sporting goods remains limited. A key barrier to wider adoption is the traditional separation of design, manufacturing, and inspection processes, which drives up cost and results in inefficiencies, sub-optimal designs, and limited feedback between lifecycle stages. In current practice, manufacturing is treated as an isolated process, disconnected from early-stage design decisions …

Integrated Power, Energy, And Thermal Management For Autonomous Hybrid Off-Road Vehicles: Multi-Timescale Modeling, Predictive Control, And Resilient Thermal Design, Anirudh Sundar

All Dissertations

Electrification and autonomy are increasingly important for off-road vehicles operating in construction, agriculture, mining, defense, and other demanding environments. These platforms must deliver high tractive power under unstructured terrain, harsh ambient conditions, low-speed operation, and large auxiliary loads. While hybrid and electrified powertrains offer improved efficiency, mobility, and auxiliary power capability, they also introduce significant challenges in managing tightly coupled power, energy, and thermal subsystems. In particular, lithium-ion batteries, power electronics, electric machines, and internal combustion engine-generator systems operate across different temperature limits and timescales, requiring coordinated management to ensure efficiency, durability, and safe operation. This dissertation develops modeling, planning, …

Microstructural Shielding And Advanced Fatigue Crack Analysis In The Presence Of Deformation Twinning, Seyed Ali Asli

All Dissertations

Design methods to mitigate fatigue failures have remained relatively stagnant, as engineers have relied on existing continuum-level models and adhered to the damage tolerance design methodology. Although damage-tolerant design has led to increased safety, extended component in-service life, and better life predictions, it still relies on maintenance routines to identify dangerous cracks. This research aims to test the hypothesis that bundles of deformation twin boundaries will increase the resistance to fatigue crack growth (FCG). Slip and twinning are two dominant mechanisms of plastic deformation in metals. Slip is more common in materials with face-centered cubic (FCC) crystal structures at room …

Investigating The Impacts Of Information Framing And Representation On Multi-Stakeholder Decision-Making For Tradespace Exploration, Meredith G. Sutton

All Dissertations

Tradespace exploration (TSE) is a decision-making process used in engineering design to search through a tradespace, containing all potential solutions to a design problem and their performance evaluations, in order to select optimal or near-optimal solutions. Solution optimality is driven by a desire to maximize the overall utility of a solution, which often cannot be done without making tradeoffs or compromises. The TSE process requires vast amounts of information which can be difficult to generate and understand, often leading to challenges including information overload, delays in decision-making, and suboptimal decisions, even for the most experienced designers. To address the challenges …

A Hybrid Machine Learning-Based Feasibility Prediction Of 3d Mechanical Designs Using Scalar And Geometric Features, Md Mohsin Uddin Fahim

Open Access Theses & Dissertations

The computational bottleneck of structural feasibility screening frequently hinders the transition from a digital 3D model to a physically manufactured component. Traditionally, engineers have relied on either overly rigid heuristic constraint checks or computationally exhaustive finite element simulations. To address this inefficiency, this thesis proposes and validates a hybrid machine-learning framework to predict the structural manufacturability of 3D mechanical designs. Moving beyond the conventional reliance on isolated scalar parameters, the proposed methodology extracts and integrates both scalar manufacturing constraints (e.g., tolerance, minimum feature thickness) and spatial geometric descriptors (e.g., bounding volume, aspect ratio) directly from STL mesh data. Utilizing a …

0905: American Car And Foundry (Acf) Collection, 1916-2019, Marshall University Special Collections

Guides to Manuscript Collections

The collection includes only documents that were found in the plant in 2021. These primarily consist of files on capital projects from the 1970s through the 1990s. Also included are notebooks with job descriptions and classifications; ledger books containing maintenance purchase orders; quality assurance manuals; visitors register books from 1973-2019; drawings of plant machinery and operations; slides and photographs; and miscellaneous materials.

The forerunner to ACF was Ensign Manufacturing Company, founded in 1871 at Huntington, West Virginia, by William H. Barnum and Ely Ensign, both from prominent families of Lime Rock, Connecticut. It was chartered (incorporated) on November 1, 1872, …

Spatial Structure And Energy Content Of Wakes Behind Single And Arrayed Undulated Cylinders, Taiga Naomi Drucker-Boisvert, OndˇRej FerˇCák, Jérémie Auzoux, Sarah E. Smith, Zein Sadek, Rowan Moore, Christain T. Murphy, Trevor Dunt, Jennifer A. Franck, Raul Bayoan Cal

Mechanical and Materials Engineering Faculty Publications and Presentations

Biologically inspired undulated cylinder geometries significantly influence wake structure and vortex-induced vibrations in turbulent flows, yet the underlying mechanisms are not fully understood. It is further unknown how these influences extend to multi-cylinder arrays, where interacting wakes accumulate and mix. This study examines the wake characteristics of an undulated cylinder and a smooth elliptic cylinder in single- and multi-cylinder array configurations, using particle image velocimetry and proper orthogonal decomposition (POD). Relative to the smooth elliptic cylinder, the undulated geometry induces pronounced spanwise-axial variability, characterized by enhanced near-wake mean momentum and weak far-wake signatures, consistent with reduced turbulent kinetic energy. While …

Investigating Simulated Natural Gas Combined Cycle Plants (Ngcc) Performance To Address The Intermittency Of Renewables, Patrick Washington

LSU New Orleans Theses and Dissertations

The inherent intermittency of wind and solar energy challenges grid stability, requiring flexible support from natural gas combined cycle (NGCC) power plants. The objective of this study is to develop a method for evaluating the turn-down performance of the NGCC system and to identify effective strategies to operate multi-island NGCC plants to respond to intermittent power demand fluctuations driven by renewable energy integration. The simulation tool was validated against benchmark U.S. Department of Energy (DOE) subcritical Rankine cycle and NGCC cases. The methodology was then applied to evaluate part load operation, inlet fogging, hydrogen blending, and multi-island dispatch for a …

Water-Heated Maisotsenko Cycle Humidifiers: A Component-Level Study On Evaporation And Exit Brine Concentration, Omar Abdulfattah Farag Omar A. Farag

Renewable Mechanical Energy

Maisotsenko-cycle (M-cycle) Heat-and-Mass Exchangers (HMXs) are usually assessed as part of complete cooling or desalination systems, which makes the behaviour of the humidifier itself difficult to distinguish. Here, a validated model is used to examine a water-heated M-cycle humidifier as an independent component. Inlet saline-water temperature, ambient temperature, Relative Humidity (RH), and water-to-air Mass-flow Ratio (MR) were varied, and performance was described by Water Evaporation Rate (WER), outlet-air specific humidity, and outlet brine salinity. Water heating and a larger MR produced the strongest increase in moisture addition because they maintained a warmer water film and greater transfer potential. At fixed …

A Transfer-Learning And Continuous Optimization-Based Framework For Predicting Heat Treatment-Dependent Mechanical Properties Of Ded-Processed Low-Alloy Steels, Atiqur Rahman, Sung Heng Wu, Ranjit Joy, Frank Liou

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Directed energy deposition (DED) of low-alloy steels involves strongly coupled effects among alloy composition, solidification behavior, and post-deposition heat treatment, making mechanical property prediction difficult when target-domain data are limited. This study develops a transfer-learning and continuous optimization framework for predicting heat treatment-dependent yield strength (YS), ultimate tensile strength (UTS), hardness (HV), and as-solidified phase fractions of martensite, ferrite, and austenite in DED-processed low-alloy steels. A CALPHAD-based dataset was generated for 125 low-alloy steel compositions. A multilayer perceptron (MLP) surrogate was first trained as a baseline model, then fine-tuned through transfer learning and progressively updated as staged continuous optimization; the …

Decarbonizing The C3 Splitter: Performance Optimization And Environmental Impact Of Mvr Integration, Dalia A. Ali Associate Prof.

Chemical Engineering

Due to the relatively low volatility (α) of propane and propene components, their separation is one of the most energy-intensive processes in the petrochemical industry. This study evaluates the technical, environmental and thermodynamic performance of a mechanical vapor recompression (MVR) heat pump integrated into a C3 splitter, compared to a conventional steam-heated distillation column. A sensitivity study was conducted using Aspen Plus software at different pressures, reflux ratios (RR) and at turndown operations. According to the results, the MVR system uses a compressor to raise the overhead vapor pressure to 38.7 bar to operate the heater without the need for …

A Verification And Validation Framework For Model-Based Systems Engineering Using Executable Architecture Models And Integrated Simulation, Michael O. Cruz

Open Access Theses & Dissertations

Model-Based Systems Engineering (MBSE) reaches its full value when architecture does more than describe a system. It should help engineers carry stakeholder need and system intent into executable analysis, preserve the configuration and criteria used, and return evidence that can be reviewed in the same architecture context. This dissertation develops and evaluates a seven phase, architecture-driven verification and validation framework for that purpose. The framework defines the responsibilities that connect SysML architecture, controlled execution, domain simulation, configuration management, persistent data, analytics, and accountable engineering review. A reusable Cameo/SysML digital test environment plugin provides the reference implementation for orchestration and model …

Thermal Degradation Analysis Of Bagasse Fibers From Sugarcane Waste, Rashmitha Suresh, Faisal Al Nasser

Journal of Mechanical Engineering Science and Technology (JMEST)

Sugarcane is one of the important commodities in the industry where bagasse fiber as waste is abundantly available.   Sugarcane bagasse fiber has high cellulose, a key element in the utilization of bagasse. Chemical pretreatment is important to prepare the natural fiber before used as composite reinforcement. The purpose of the study is to analyze the thermal degradation of bagasse fiber after being treated using NaOH and TEMPO solution. The manufacturing method was carried out by a series of washing bagasse with distilled water and NaOH solution, subsequently soaking it in 6% NaOH and 2,2,6,6-tetramethylpiperidine-l-oxyl (TEMPO) solution, and conducted oven-dried. Thermogravimetric …

Emergent De Sitter Expansion And Closed Topology From The Cosmic Fabric Model As An Open Thermodynamic System: Resolving The Negative Bulk Modulus Paradox, T G. Tenev, C B. Ward, T F. Tenev, M F. Horstemeyer

Faculty Publications and Presentations

The Cosmic Fabric Model establishes a continuum-mechanics isomorphism to General Relativity by representing physical space as an elastic three-dimensional hyperplate embedded in a four-dimensional spatial bulk. Reproducing vacuum kinematics requires a vanishing P-wave modulus, which in turn implies a negative bulk modulus—an apparent thermodynamic instability in a closed system. This paradox is resolved by recasting the framework as an open system: the instability is not pathological but instead drives cosmic expansion. In this interpretation, the observable universe is a lower-energy solid formed through continuous solidification from a higher-dimensional precursor fluid. Using multiplicative kinematics from finite-growth mechanics, the model shows that …

Development Of Dynamic Proof-Mass Configurations For Broadband Piezoelectric Energy Harvesting, Nico E. Galarza

Electrical and Computer Engineering ETDs

The purpose of this thesis is to investigate and develop dynamic proof-mass configurations for broadband piezoelectric energy harvesting. Conventional piezoelectric energy harvesters are typically limited by narrow operating bandwidths, restricting their performance under variable-frequency excitation. This research presents the design, fabrication, and experimental evaluation of multiple proof-mass concepts intended to increase the usable frequency range of cantilever-based piezoelectric energy harvesters. Several dynamic mass configurations were developed using additive manufacturing techniques and integrated with commercially available piezoelectric cantilevers. Experimental testing was conducted under controlled vibration conditions to characterize voltage response, resonant behavior, and bandwidth performance. The results demonstrate that dynamic proof-masses …

Developing Simulation To Improve G3p3 Efficiencies, Andrew Gaudette

Mechanical Engineering ETDs

Concentrated solar power (CSP) systems offer a promising method of renewable energy generation by using heliostats to focus sunlight onto a falling particle receiver. At the National Solar Thermal Testing Facility (NSTTF), particles absorb and store solar energy for later power generation. A major source of efficiency loss is wind-driven particle escape through the receiver aperture. This thesis develops computational fluid dynamics (CFD) simulations to characterize wind flow around the G3P3 falling particle receiver and support future wind mitigation strategies. Numerical studies were conducted to establish an appropriate simulation methodology. Iteration studies showed that 2,000 iterations were sufficient for convergence, …

Control Of Reshock In A Shock Tube, Alexander Sweis

Mechanical Engineering ETDs

Reshocks can pose a threat to the structural integrity of structures and buildings. While incident shock waves pose larger threats, the study of reshocks and reshock attenuation is important to consider. This thesis investigates methods for controlling and attenuating reshock strength within a shock tube through material-based damping and modifications to baffle box geometric configurations. Experiments are performed using a custom-built shock tube in the University of New Mexico fluid mechanics laboratory. Four baffle box configurations are examined: a foam-lined configuration, a foam-lined configuration with ”egg crate-like” textured foam, an empty (no foam) configuration, and a configuration which incorporates a …

Investigating Light-Matter Interactions In Low-Dimensional Silicon Carbide, Nishan Shrestha

Mechanical Engineering ETDs

Recent advances in materials science have transformed the study and application of low-dimensional materials, with two-dimensional (2D) systems and nanoscale structures exhibiting properties beyond their bulk counterparts. Despite significant progress in materials such as graphene and silicon, the nanoscale exploration of silicon carbide (SiC) remains relatively underdeveloped, despite its critical importance in photonics and electronics and high temperature applications. Motivated by the transformative potential of nanoscale material design and the technological importance of SiC, this dissertation investigates structure and properties of low-dimensional silicon carbide structures. It explores the synthesis and optical properties of SiC nanosheets and nanowires using a variety …

Analysis Of Electronic Control Unit Optimization On The Performance Of A 150 Cc Motorcycle Engine Using Ethanol-Blended Fuel, Agus Achmad Syaiful, Annisa Bhikuning, Muhammad Rizal Baihaqi, Muhammad Aulia Rafli

Journal of Mechanical Engineering Science and Technology (JMEST)

The use of ethanol-blended fuel in a standard vehicle can reduce combustion quality, which has an impact on decreasing vehicle performance. At the above 20% blend level, it affects vehicle performance and requires adjustments to engine settings or the Electronic Control Unit (ECU) before use on conventional engines. This study investigates the effect of aftermarket ECU settings on the performance of a 150 cc motorcycle operating on a gasoline-ethanol blend. Four fuel variations were tested: Pertalite (P100), revvo 90 (R100), and 30% ethanol blends (PE30 and RE30). This study analyzes the effects of optimizing injection duration and ignition timing settings …

Object Avoidance Onboard An Autonomous Underwater Vehicle In Support Of Geomagnetic Based Navigation System, Eric Benavidez

Electronic Theses and Dissertations 2020 - Present

The objective of this thesis was to collect and analyze magnetic field data in the vicinity of the Mercy, Tracey, and Jay Scutti with an autonomous underwater vehicle (AUV) and a forward mounted magnetometer. The collected data was used to develop geomagnetic contour maps and magnetic thresholds of known anomalies to compare the results with validated sources such as NOAA.

In addition, this collected data was used to develop a Gazebo simulation which accurately modeled the magnetic field data and ocean effects of the Fort Lauderdale Shipwreck Trail. This Gazebo simulation allowed for proper testing and refinement of object avoidance …

Chemical Composition Stability Of Cu–Sn And Cu–Zn Journal Bechemical Composition Stability Of Cu–Sn And Cu–Zn Alloys Fabricated By Sand And Permanent Mold Casting With Nickel Alloying, Erwin Erwin, Didik Sugiyanto, Juan Pratama, Trisna Ardi Wiradinata, Abdul Rachmadhan, Muhammad Fikri Andika

Journal of Mechanical Engineering Science and Technology (JMEST)

The processes of moulding and reinforcing chemical elements have a big impact on the balance of chemical composition in copper-based bearing alloys. This has a direct impact on how well the material works. This study examines Cu–Sn alloys produced via sand casting and Cu–Zn alloys fabricated through permanent mould casting, with the incorporation of nickel, which remains uncommon. The objective was to examine the variations in the equilibrium of the chemical composition and the performance potential of the bearing alloy metal when subjected to different casting techniques and nickel concentrations ranging from 0% to 4%. Some of the methods used …

Effect Of Concentration And Temperature Of Tio2-Al2o3 Hybrid Nanofluid On The Corrosion Rate Of Aluminum Radiator, Ratna Monasari, Rizky Maulana Ramadhan, Nike Nur Farida, Ahmad Hanif Firdaus, Supa Kusuma Aji, Yuniarto Agus Winoko, Rizkyansyah Alif Hidayatullah

Journal of Mechanical Engineering Science and Technology (JMEST)

Corrosion of aluminum radiators can reduce cooling system reliability and shorten service life in automotive applications. This study examines the effect of TiO₂-Al₂O₃ hybrid nanofluid concentration and temperature on the corrosion rate of commercially available aluminum radiator material. Hybrid nanoparticles with a TiO₂-Al₂O₃ mass ratio of 50:50 were dispersed in distilled water at concentrations of 0.6 wt.%, 0.8 wt.%, and 1.0 wt.%. Corrosion behavior was evaluated using a 14-day accelerated immersion test at 60°C and 80°C, and the corrosion rate was determined using the gravimetric mass loss method. The results …

Experimental Evaluation Of Membranes In The Recovery Of Hydrogen From Serpentinization, Rafael Dos Santos

LSU Master's Theses

Natural hydrogen generated through serpentinization reactions has emerged as a promising low-carbon energy resource. However, serpentinization-derived gas streams commonly contain methane (CH₄) and carbon dioxide (CO₂), requiring purification before hydrogen can be utilized in industrial applications. Membrane-based gas separation technologies offer a potentially cost-effective solution for hydrogen recovery; however, to the best of the author's knowledge, no previous studies have specifically investigated their application to serpentinization-derived gas streams.

This work evaluates the performance of two commercial polymeric membrane modules (Evonik and Generon) and one palladium-copper (Pd-Cu) membrane module (Okaya) for hydrogen recovery from gas compositions representative of serpentinization environments. An …

Global Time-Resolved Measurements Of Inlet/Isolator Unstart Induced By Mass Injection, Andrew N. Bustard, Benjamin L. Bemis, Aaron Marques, Matthew J. Zahr, Thomas J. Juliano

Publications

The inner surface pressure of an axisymmetric inlet/isolator model was measured using anodized-aluminum pressure-sensitive paint (PSP) viewing through cast acrylic. Temperaturesensitive paint was utilized to correct for the PSP’s temperature sensitivity. The model was tested under Mach 5.7 flow at 𝑹𝒆 = 7.1 ×106 /m under conventional noise conditions. Transverse jet injection with jet-to-inlet mass-flow ratios up to 0.8 was used to induce unstart in the inlet/isolator. Background-oriented schlieren visualization of the inlet shocks was collected simultaneously with the PSP to determine when the inlet unstarted. Computational fluid dynamics results were used to determine off-wall flow structures and quantify approach …

Straw As A Potential Vegetable Fibre Insulative Infill In Framed Constructions - Material Testing\Tnotereftnote1, Patrick Daly

Journal of Sustainable Construction Materials and Technologies

The construction sector faces increasing pressure to reduce embodied carbon and adopt circular material strategies, with bio-based materials offering a promising pathway. Straw-based insulation, particularly in loose-fill form, has gained traction in Europe, where several products have achieved certification under EAD 040138-01-1201. This study investigates the potential of Irish-processed straw chip as a bio-based insulative infill for framed construction by evaluating its material properties and thermal conductivity–density performance relative to European ETA-certified reference products. A programme of laboratory testing was undertaken on commercially available Irish straw samples, including material characterisation (moisture content, particle morphology, and dust content) and thermal conductivity …

Development And Characterization Of Mycelium-Based Biocomposites From Ganoderma Lucidum Using Spent Yerba Mate And Residual Sunflower Oil For Sustainable Insulation In Construction, Paula V. Alfieri, Guadalupe Canosa

Journal of Sustainable Construction Materials and Technologies

The construction industry urgently requires sustainable alternatives to petroleum-based insulation materials such as expanded polystyrene (EPS) and mineral wool. Mycelium-based biocomposites offer a promising solution by valorizing agricultural waste while delivering competitive thermal and acoustic performance. In this study, developed and characterized biocomposites using Ganoderma lucidum mycelium combined with spent yerba mate and residual sunflower oil (70 g/30 mL), both commonly generated as waste in Argentine institutions. Two formulations were evaluated: high density (HD: 280 ± 5 kg/m³) and low density (LD: 185 ± 5 kg/m³). Samples were cultivated for 90 days at 28 °C and 65% relative humidity and …

Comparative Life Cycle Assessment Of Hemp Walls In Residential Construction In Morocco, Hicham Kaddouri, Rachida Elbarghmi, Firyal Latrache, Marwane Hammouti, Abderrahim Abidouche, Ismael Driouch

Journal of Sustainable Construction Materials and Technologies

This study analyzes the energy and environmental performance of hemp-based wall solutions applied to Moroccan residential buildings by combining dynamic thermal simulation and life cycle assessment (LCA). A reference building is assessed under four representative Moroccan climates (Al Hoceima, Oujda, Marrakech, and Ouarzazate), comparing a conventional wall retrofitted with hemp plaster and a wall incorporating hemp concrete. The results show that hemp concrete significantly reduces annual heating and cooling energy demands by 20–24% depending on the climate, with heating needs decreasing by up to 40% and cooling needs by approximately 15%, particularly in hot and arid regions. The LCA reveals …

Dual-Waste Integration For Geotechnical Improvement: Silica Fume And Eggshell Ash In Kaolin Soil Stabilization, Ng Jun Shen, Muzamir Hasan, Siti Sarah Eliyun, Md. Ikramul Hoque, Mohamad Afiq Jazrin Mohamad Sidek

Journal of Sustainable Construction Materials and Technologies

This study reveals the potential substitution of silica fume and eggshell ash in the technique of soil stabilization, varying across distinct proportions in the modification of geotechnical parameters. The untreated kaolinitic soil which has low soil bearing capacity in nature is frequently reflected in its mechanical instability, for instance, soil settlement and extreme compressibility. By associating the industrial and agricultural material, it is potentially to resolve the above-mentioned issues with explicit designs. A number of laboratory approaches have been implemented in the assessment of basic geotechnical properties, including grain size distribution, Atterberg limits, specific gravity, proctor properties, and shear strength …