Engineering Commons^™

Search Methods For Mobile Manipulator Performance Measurement, Samuel Nana Yaw Amoako-Frimpong

Master's Theses (2009 -)

Mobile manipulators are a potential solution to the increasing need for additional flexibility and mobility in industrial robotics applications. However, they tend to lack the accuracy and precision achieved by fixed manipulators, especially in scenarios where both the manipulator and the autonomous vehicle move simultaneously. This thesis analyzes the problem of dynamically evaluating the positioning error of mobile manipulators. In particular, it investigates the use of Bayesian methods to predict the position of the end-effector in the presence of uncertainty propagated from the mobile platform. Simulations and real-world experiments are carried out to test the proposed method against a deterministic …

Field Validation Of An Advanced Autonomous Method Of Exterior Dam Inspection Using Unmanned Aerial Vehicles, Benjamin Joseph Barrett

Theses and Dissertations

The maintenance of infrastructure is critical to the well-being of society. This work focuses on a novel method for inspecting the exterior of dams using unmanned aerial vehicles (UAVs) in an automated fashion. The UAVs are equipped with optical sensors capturing still images. The resulting images are used to generate three-dimensional (3D) models using Structure from Motion (SfM) computer software. The SfM models are then used to inspect the exterior of the dam. As typical dam inspections entail completing a checklist of inspection items with varied degrees of precision (e.g. a concrete spillway may be finely inspected for cracking or …

The Impact Of Nanostructured Templates And Additives On The Performance Of Si Electrodes And Solid Polymer Electrolytes For Advanced Battery Applications, Jui Chin Fan

Theses and Dissertations

The primary objectives of this research are: (1) use a hierarchical structure to study electrode materials for next-generation lithium-ion batteries (LIBs) and (2) understand the fundamentals and utility of solid polymer electrolytes (SPEs) with the addition of halloysite nanotubes (HNTs) for battery applications. Understanding the fundamental principles of electrode and electrolyte materials allows for the development of high-performance LIBs. The contributions of this dissertation are described below. Encapsulated Si-VACNT Electrodes. Two hurdles prevent Si-based electrodes from mass production. First, bulk Si undergoes volume expansion up to 300%. Second, a solid-electrolyte interphase (SEI) forms between the interface of the electrolyte and …

Homogeneous Reaction Kinetics Of Carbohydrates With Viologen Catalysts For Biofuel Cell Applications, Hilary Bingham

Theses and Dissertations

Energy usage is continually on the rise and significant efforts are being extended to provide more renewable energy. One area of exploration is the development of fuel cells, which includes biofuel cells that can extract energy from carbohydrates obtained from biomass. Recently, viologen catalysts have been shown to enhance reaction rates of energy extraction and improve carbohydrate conversion efficiencies. However, characterizing the effects of process parameters such as pH, reactant concentrations, and carbohydrate exposure time to buffer solutions with a rigorous model is lacking. This thesis characterizes the homogeneous reaction between carbohydrates and a methyl viologen catalyst to provide insights …

Tactile Sensing And Position Estimation Methods For Increased Proprioception Of Soft-Robotic Platforms, Nathan Mcclain Day

Theses and Dissertations

Soft robots have the potential to transform the way robots interact with their environment. This is due to their low inertia and inherent ability to more safely interact with the world without damaging themselves or the people around them. However, existing sensing for soft robots has at least partially limited their ability to control interactions with their environment. Tactile sensors could enable soft robots to sense interaction, but most tactile sensors are made from rigid substrates and are not well suited to applications for soft robots that can deform. In addition, the benefit of being able to cheaply manufacture soft …

Smart Technologies For Oil Production With Rod Pumping, Brigham Wheeler Hansen

Theses and Dissertations

This work enables accelerated fluid recovery in oil and gas reservoirs by automatically controlling fluid height and bottomhole pressure in wells. Several literature studies show significant increase in recovered oil by determining a target bottomhole pressure but rarely consider how to control to that value. This work enables those benefits by maintaining bottomhole pressure or fluid height. Moving Horizon Estimation (MHE) determines uncertain well parameters using only common surface measurements. A Model Predictive Controller (MPC) adjusts the stroking speed of a sucker rod pump to maintain fluid height. Pump boundary conditions are simulated with Mathematical Programs with Complementarity Constraints (MPCCs) …

Logistics And Funding Plan For The Simpson Strong-Tie Lab Crane, Arya Ghourchian

Construction Management

In the recent years, there has been interests regarding an overhead crane to be erected inside of Cal Poly Simpson Strong-Tie Lab (Building 187). This under-running single girder crane system will be used for construction classes and to lift heavy equipment. The installment of this 2-ton indoor crane will be crucial to provide modular pieces, for whom that lost their homes due to the California fires. Additionally, there has been previous senior project researches; reference SST Preconstruction Services and Structural Analysis of SST Lab. I am in charge of collecting information regarding: Bid Estimate Comparison, Advertisement Strategy, Permit Compliance. This …

Enhancing Manual P-Phase Arrival Detection And Automatic Onset Time Picking In A Noisy Microseismic Data In Underground Mines, Charles Mborah, Maochen Ge

Mining Engineering Faculty Research & Creative Works

Accurate detection and picking of the P-phase onset time in noisy micro seismic data from underground mines remains a big challenge. Reliable P-phase onset time picking is necessary for accurate source location needed for planning and rescue operations in the event of failures. In this paper, a new technique based on the discrete stationary wavelet transform (DSWT) and higher order statistics is proposed for processing noisy data from underground mines. The objectives of this method are to (i) improve manual detection and picking of P-phase onset; and (ii) provide an automatic means of detecting and picking P-phase onset time accurately. …

Aerothermodynamic Analysis Of A Mars Sample Return Earth-Entry Vehicle, Daniel A. Boyd

Mechanical & Aerospace Engineering Theses & Dissertations

Because of the severe quarantine constraints that must be imposed on any returned extraterrestrial samples, the Mars sample return Earth-entry vehicle must remain intact through sample recovery. Vehicles returning on a Mars-Earth trajectory will attain velocities exceeding any that have been experienced by prior space exploration missions, with velocities approaching 14 km/s. Velocities as high as these will encounter significant heating during atmospheric re-entry to Earth.

The purpose of this study has been to systematically investigate the aerothermodynamic challenges that will result from a Mars sample return, Earth-entry vehicle design. The goal was to enable efficient estimation of maximum stagnation …

Effects Of Automated Fiber Placement On High Strain Rate Compressive Response Of Advanced Composites, Alexander Trochez

Mechanical & Aerospace Engineering Theses & Dissertations

Automated Fiber Placement (AFP) technology shows great promise in manufacturing carbon fiber composite structures. However, intermittent defects occur in the process that can affect the overall mechanical performance of the structure. The aim of this work is to investigate the effects of deliberately placed principal defects (Gap, Overlap, and Fold) on the compressive response under quasistatic (strain rate ~10^-3 s^-1) and dynamic (strain rate ~10³ s-1) loading conditions. The controlled defects were placed at the laminate level in different orientations and depths. High strain rate compression experiments were conducted using a split Hopkinson pressure bar (SHPB) …

A Stepwise Compression-Relaxation Testing Method For Tissue Characterization And Tumor Detection Via A Two-Dimensional Tactile Sensor, Yichao Yang

Mechanical & Aerospace Engineering Theses & Dissertations

This dissertation presents a stepwise compression-relaxation (SCR) testing method built upon a two-dimensional (2D) tactile sensor for mechanical characterization of soft tissues and tumor detection. The core of the 2D sensor entails one whole polydimethylsiloxane (PDMS) microstructure embedded with a 3×3 sensing-plate/transducer array. A soft sample was compressed by the 2D sensor with a step incremental depth at a ramp speed, and then relaxed for certain hold time. When a soft sample was compressed by the 2D sensor, the sensing-plates translated the sample response at different tissue sites to the sensor deflections, which were registered as resistance changes by the …

Optimization Of Top Contact For Cu(In,Ga)Se2 Solar Cells, Grace Cherukara Rajan

Electrical & Computer Engineering Theses & Dissertations

As world energy demands continue to increase, the need to generate electricity from a broader variety of sources, including renewables, is more critical than ever. With costs still 30% higher than those of natural gas, solar energy is a viable contender, but more progress is needed to level the playing field with other forms of energy generation. The overall energy security can be enhanced by diversifying the energy supply. Among them, Cu(In,Ga)Se₂ (CIGS) has gained significant momentum as a possible high efficiency and low cost thin film solar cell material. The capacity to scale up any photovoltaic technology is …

Dynamic Behavior Of Granular Earth Materials Subjected To Pressure-Shear Loading, Jeff Wilson Lajeunesse

Dissertations (1934 -)

The dynamic response of granular earth materials such as sand has been of interest for many years. Multiple previous works have explored the shock response of sand in various grain shapes, sizes, and moisture contents, but the response during rapid combined loading has been relatively unexplored. The current study contributes to that lack of data by performing pressure-shear experiments on Oklahoma #1 silica sand, with quasi-smooth grains of 63 - 120 micron diameter and 99.8 wt.% Si02 composition. In these experiments, an oblique flyer plate impacts an equally inclined target, imparting a longitudinal (pressure) and transverse (shear) wave into a …

The Effectiveness Of Localized Ultrasound And Aptamer Surface Modification On Nanoemulsions For Drug Delivery To Spheroids., Daniel A. Hodge

Electronic Theses and Dissertations

Cancer is a group of diseases that affects 1.6 million and kills nearly 600,000 Americans each year. The National Cancer Institute defines it as “diseases in which abnormal cells divide without control and can invade nearby tissues” and it is often treated with one or more of the following: chemotherapy, radiation, surgery. The expense for these treatments is expected to rise to $156 billion by 2020. Localized delivery can improve effectiveness and cancer survival rates, decrease the cost of treatment, and decrease the side effects of chemotherapy. This paper addresses models for this localized delivery through nanoemulsions. Nanoemulsions are a …

Tooling For Injection Molding Using Laser-Powder Bed Fusion., Mohith Ram Buxani

Electronic Theses and Dissertations

Laser-Powder Bed Fusion (L-PBF) has been considered for some time by the injection molding industry for the fabrication of tooling for injection molding in order to address large lead times and costs for tool-making. Computer-aided simulations are also routinely used to evaluate new part and mold designs as well as understanding the effects of material compositions and processing conditions on part quality and overall productivity. However, there remains a significant need to integrate the perspectives from injection molding, 3D printing, metal powders, and component design and process simulation to better utilize LPBF for fabricating tooling required for injection molding. The …

Smart Bandage For Monitoring And Treatment Of Chronic Wounds, Pooria Mostafalu, Ali Tamayol, Rahim Rahimi, Manuel Ochoa, Akbar Khalilpour, Gita Kiaee, Iman K. Yazdi, Sara Bagherifard, Mehmet R. Dokmeci, Babak Ziaie, Sameer R. Sonkusale, Ali Khademhosseini

Department of Mechanical and Materials Engineering: Faculty Publications

Chronic wounds are a major health concern and they affect the lives of more than 25 million people in the United States. They are susceptible to infection and are the leading cause of nontraumatic limb amputations worldwide. The wound environment is dynamic, but their healing rate can be enhanced by administration of therapies at the right time. This approach requires real-time monitoring of the wound environment with on-demand drug delivery in a closed-loop manner. In this paper, a smart and automated flexible wound dressing with temperature and pH sensors integrated onto flexible bandages that monitor wound status in real-time to …

A Robot Fdm Platform For Multi-Plane And 3d Lattice Structure Printing, Ismayuzri Bin Ishak

Theses and Dissertations

Additive manufacturing is a process to fabricate three-dimensional (3D) objects usually by joining a material layer by layer. The layer by layer joining process simplifies the fabrication method by slicing the 3D object into stacks of 2D contours. The layers are combined in a single build direction to form the 3D object. The purpose of this research is generate new knowledge in additive manufacturing process by integrate a six degree of freedom robot arm platform with a fused deposition modeling system entitled MotoMaker for additive manufacturing applications. The development of a higher degree of freedom additive manufacturing platform allows for …

Antimicrobial Properties And Characterization Of Polymer/Composite Nanofibers, David De La Garza

Theses and Dissertations

Pathogenic bacteria have been the cause of many illnesses worldwide due to their rapid growth and reproduction in food and water. Bacteria-resistant antibiotics and kidney complications due to overuse of antibiotics has remained a large public health concern. The goal of this research project was to find an alternative by producing nanofibers that inhibit microbial growth utilizing Forcespinning technology. The Forcespinning of poly(acrylic acid) (PAA) with Single Wall Carbon Nanotubes functionalized with OH (SWCNT-OH) and Ag + flakes were carried out on solutions with different concentrations. Scanning electron microscopy was used to view fiber morphology and investigate the average nanofiber …

Forcespinning Of Metal Oxides And Metal Sulfides And Their Applications As Alternative Anode Materials For Lithium-Ion And Sodium-Ion Batteries, Alejandra Valdez

Theses and Dissertations

Molybdenum-Oxide/Carbon (MoO2/C) composite nanofibers were synthesized using Forcespinning method and subsequent heat treatment, for use as anode materials for lithium-ion batteries. Due to the layered structure of MoO2, the composite nanofibers are very promising for use as anode material for LIBs. The MoO2/C composite fiber anodes exhibit good electrochemical performance and cycling stability.

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Building Services Engineering

No abstract provided.

Adopt: Combining Parameter Tuning And Adaptive Operator Ordering For Solving A Class Of Orienteering Problems, Aldy Gunawan, Hoong Chuin Lau, Kun Lu

Research Collection School Of Computing and Information Systems

Two fundamental challenges in local search based metaheuristics are how to determine parameter configurations and design the underlying Local Search (LS) procedure. In this paper, we propose a framework in order to handle both challenges, called ADaptive OPeraTor Ordering (ADOPT). In this paper, The ADOPT framework is applied to two metaheuristics, namely Iterated Local Search (ILS) and a hybridization of Simulated Annealing and ILS (SAILS) for solving two variants of the Orienteering Problem: the Team Dependent Orienteering Problem (TDOP) and the Team Orienteering Problem with Time Windows (TOPTW). This framework consists of two main processes. The Design of Experiment (DOE) …

Preparation And Characterization Of Functionalized Heparin-Loaded Poly-Ɛ-Caprolactone Fibrous Mats To Prevent Infection With Human Papillomaviruses, Daniela Gonzalez, Jorge Ragusa, Peter C. Angeletti, Gustavo F. Larsen

Department of Chemical and Biomolecular Engineering: Faculty Publications

In this study, heparin-loaded poly-ε-caprolactone (PCL) fibrous mats were prepared and characterized based on their physical, cytotoxic, thermal, and biological properties. The main objective of the work described here was to test the hypothesis that incorporation of heparin into a PCL carrier could serve as bio-compatible material capable of inhibiting Human Papillomavirus (HPV) infection. The idea of firmly anchoring heparin to capture soluble virus, vs. a slow heparin release to inhibit a virus in solution was tested. Thus, one material was produced via conventional heparin matrix encapsulation and electrohydrodynamic fiber processing in one step. A second type of material was …

Numerical Modelling Of Red Blood Cell Structural Mechanics, Mingzhu Chen

Doctoral

Red blood cells (RBCs) are the most abundant cellular elements in blood and their main function is the oxygen delivery. Structurally RBCs are highly deformable membrane-bounded liquid-core capsules. The deformability is critical to fulfill the functionality and is greatly affected by the RBC structural mechanics. Due to the small size, in vivo/vitro studies of the RBCs are often impossible where, being an alternative, numerical modellings stand out to be a robust approach to investigate the the RBC. In the recent years the spring-particle-based (SP) RBC modelling becomes very popular due to the simplicity and extensive modelling capability over the conventional …

Exploring Offline Friendships On The Social Information Network: Network Characteristics, Information Diffusion, And Tie Strength, Felicia Natali

Dissertations and Theses Collection (Open Access)

The rapid increase in online social networking services over the last decade has pre- sented an unprecedented opportunity to observe users’ behaviour both on a societal and individual level. The insight gained from analysing such data can help foster a deeper understanding of social media users and the flow of information, while also offering valuable business applications. User relationships are among the most studied aspects of online behaviour. These relationships are not homogeneous. Past research has shown that people use social networks to both socialize and source in- formation. Hence, different types of links – used to socialize, gain information, …

Gekko Optimization Suite, Logan Beal, Daniel Hill, Ronald Abraham Martin, John Hedengren

Faculty Publications

This paper introduces GEKKO as an optimization suite for Python. GEKKO specializes in dynamic optimization problems for mixed-integer, nonlinear, and differential algebraic equations (DAE) problems. By blending the approaches of typical algebraic modeling languages (AML) and optimal control packages, GEKKO greatly facilitates the development and application of tools such as nonlinear model predicative control (NMPC), real-time optimization (RTO), moving horizon estimation (MHE), and dynamic simulation. GEKKO is an object-oriented Python library that offers model construction, analysis tools, and visualization of simulation and optimization. In a single package, GEKKO provides model reduction, an object-oriented library for data reconciliation/model predictive control, and …

A Parametric Electrostatic Resonator Using Repulsive Force, Mark Pallay, Shahrzad Towfighian

Mechanical Engineering Faculty Scholarship

In this paper, parametric excitation of a repulsive force electrostatic resonator is studied. A theoretical model is developed and validated by experimental data. A correspondence of the model to Mathieu's Equation is made to prove the existence and location of parametric resonance. The repulsive force creates a combined response that shows parametric and subharmonic resonance when driven at twice its natural frequency. The resonator can achieve large amplitudes of almost 24 μm and can remain dynamically stable while tapping on the electrode. Because the pull-in instability is eliminated, the beam bounces off after impact instead of sticking to the electrode. …

An Analysis Of The Relationship Between Orthopedic Drill Bit And Screw Diameter On Drilling Energy And Axial Load Pullout Strength, Scott J. J. Baskerville

Theses and Dissertations

The number of orthopedic procedures performed per year in the United States is expected to grow to 6.6 million by 2020 (1). Most of these surgeries involve some degree of bone drilling and screw fixation, putting many patients at risk of the adverse effects of the heat-induced osteonecrosis which can limit the holding strength of bone screws and the efficacy of the screw-dependent fixtures. Excessive heat-induced osteonecrosis can occur when surgeons prolong the drilling procedure to avoid drill plunge, which can cause damage to soft neurovascular tissues local to the drilling site (2). The SMARTdrill system used in this study …

Direct Numerical Simulations Of Incompressible Flow Through Porous Packs Over A Wide Range Of Reynolds Numbers, Antoine Michael Diego Jost

Theses and Dissertations

Direct numerical simulations of incompressible flow through periodic square/rectangular (two-dimensional; 2-D) and cubic (three-dimensional; 3-D) arrays of particles and periodic random packs of polydisperse spheres over a wide range of Reynolds numbers and at various porosities are performed. The unsteady Navier- Stokes equations are solved with either a 3-D parallel finite-difference (FD) inhouse research code on a collocated Cartesian grid and with an immersed boundary method (IBM) to treat the internal boundaries, or with the finite-volume (FV) solver OpenFOAM R⃝ on an unstructured grid and with an explicit treatment of the boundaries. The FD explicit solver is used for 2-D …

Improving Stb Devices’ Parental Control, Mahmood Fawzi Alfathe

Theses and Dissertations

In this dissertation, an IPTV system was designed with new viewer parental control authentication method. People deal with traditional IPTV systems that use simple authentication numeric passcodes, and this topic did not receive the attention to overcome its security problems. In this dissertation two contributions were introduced, the first one is to design and implement an IPTV system that uses humans’ Biometrics authentication instead of numeric passwords; the second contribution was presented by integrating and testing the efficiency of the suggested solution as an authentication key against traditional numerical passcodes. Also, the characteristics of this new method were tested. In …

Effects Of Nb And Ta Additions On The Strength And Coarsening Resistance Of Precipitation-Strengthened Al-Zr-Sc-Er-Si Alloys, Dinc Erdeniz, Anthony De Luca, David N. Seidman, David C. Dunand

Mechanical Engineering Faculty Research and Publications

A dilute Al-0.07Zr-0.02Sc-0.005Er-0.06Si (at.%) alloy was microalloyed with 0.08 at.% Nb or Ta. Atom-probe tomography reveals that, upon aging, Nb and Ta partition to the coherent L1₂-Al₃(Zr,Sc,Er) nanoprecipitates (with average concentrations of 0.2 and 0.08 at.%, respectively), with both segregating at the matrix/nanoprecipitate heterophase interface. This is consistent with the Nb- and Ta-modified alloys exhibiting, as compared to the unmodified alloy: (i) higher peak microhardness, from a higher nanoprecipitate volume fraction and/or latticeparameter mismatch; and (ii) improved aging resistance, from slower nanoprecipitate coarsening due to the small diffusivities of niobium and tantalum in aluminum. Analogous results …