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Design And Testing Of A Nanosatellite Simulator Reaction Wheel Attitude Control System, Fredric William Long

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

Attitude control of a satellite is required for the pointing of communications antennas and other instruments. For this reason, a control algorithm capable of precision pointing is important. Because the process of sending a satellite into space is time consuming and costly, ground-based methods of testing are paramount. A simulator is a low-cost, groundbased system made to mimic the conditions of a weightless satellite in space. The simulator used in this project controls attitude through applying torque to reaction wheels. The objective of this project is to derive and test a control algorithm for the attitude control of a satellite …

Numerical Examination Of Flux Correction For Solving The Navier-Stokes Equations On Unstructured Meshes, Dalon G. Work

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This work examines the feasibility of a novel high-order numerical method, which has been termed Flux Correction. This is accomplished by comparing it against another high-order method called Flux Reconstruction. These numerical methods are used to solve the Navier-Stokes equations, which govern the motion of fluid flow. High-order numerical methods, or those that demonstrate a third-order and higher solution error convergence rate, are rarely used on unstructured meshes when solving fluid problems. Flux Correction intends to make high-order accuracy available to the larger world of Computational Fluid Dynamics in a simple and effective manner. The advantages and disadvantages of the …

Spacecraft Guidance Techniques For Maximizing Mission Success, Shane B. Robinson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Traditional spacecraft guidance techniques have the objective of deterministically minimizing fuel consumption. These traditional approaches to guidance are developed independently of the navigation system, and without regard to stochastic effects. This work presents and demonstrates a new approach to guidance design. This new approach seeks to maximize the probability of mission success by minimizing the variance of trajectory dispersions subject to a fuel consumption constraint. The fuel consumption constraint is imposed by formulating the dynamics in terms of a steering command, and placing a constraint on the final time. Stochastic quadratic synthesis is then used to solve for the nominal …

Experimental Studies Of Delta Wing Parameters In Open Channel Raceway Determined Via Validated Computational Fluid Dynamics, Cole David Blakely

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A promising feedstock for biofuels is microalgae. The most economical means of cultivating microalgae is via open raceway ponds. However, a large gap in economic feasibility exists between algae-based biofuels and traditional petroleum fuels. Recent research at Utah State University has focused on increasing biomass growth by implementing Delta Wings (DWs). DWs are placed facing the incoming flow, with a 40 degree angle of attack to create large vortices which travel downstream. The trailing vortices increase vertical mixing, which in turn increases algal growth.

Past researchers at USU quantified vertical mixing with new metrics, optimized various raceway operating conditions, and …

Bridging The Nano- And Macro-Worlds: Thermal Property Measurement Using Thermal Microscopy And Photothermal Radiometry – Application To Particle-Irradiation Damage Profile In Zirconium Carbide, Colby Bruce Jensen

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Multiscaled experimental investigations of heat transfer from nanoscales to macroscales are requisite to progress in energy technologies. In nuclear applications, material properties can undergo significant alteration due to destructive interaction with irradiating particles at microstructural levels that affect bulk properties. This study expands the current knowledge base regarding thermal transport in ion-irradiated materials through the use of a multiscaled experimental approach using four complementary thermal wave methods. For the first time, the in-depth thermal conductivity profile of an ion-irradiated sample is measured directly.

Retrofitting Two Solar Hot Water Systems For Year Round Operation, Zachary A. Cook

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

Solar energy in a variety of applications is again becoming more widely used. Solar collectors have been installed during the construction of two Utah State University buildings: Wetlands Discovery located in Kaysville, Utah and Swaner Nature Preserve located in Park City, Utah. While these systems are capable of capturing a significant amount of solar energy, problems have been encountered when the demand is less than the system’s capacity. This project report documents the problems encountered while operating the two solar water heating systems and how the systems were modified to be operational year round under typical operating conditions. The peak …

The Analysis And Manufacturing Of The Personal Vacuum Assisted Climber Ii, Rhet B. Astle

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The Personal Vacuum Assisted Climber or PVAC for short (as shown in Fig 2) is a new means for climbing walls. Unlike ordinary climbing methods used today, the PVAC scales walls via suction. This suction is produced by three spinning impellers within each vacuum motor, which removes air from a sealed area. A climber pulls down on a vacuum pressure release mechanism to release the vacuum. Foot stirrups are used by the climber to climb to the next higher step. This allows the strength of the climber's legs to lift his/her body reducing arm fatigue, allowing rapid ascension of any …

The Design And Testing Of A Three-Degree-Of-Freedom Small Satellite Simulator Using A Linear Controller With Feedback Linearization And Trajectory Generation, Marina A. Samuels

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A small satellite simulator with attitude determination and control was designed and implemented in hardware. The simulator consists of inertial sensors for attitude determination and a pyramidal four-wheel momentum exchange system as the control actuators. A linearized PV controller with trajectory generation and feedback linearization was implemented, with the focus on controlling yaw. The simulator was tested on a spherical air bearing platform to allow three-degree-of-freedom operation. The simulator software was developed to read measurements from the sensors, apply the control algorithm, and send commands to the actuators. A data processing routine was developed. Electromechanical testing for the system as …

System Identification Of A Small Low-Cost Unmanned Aerial Vehicle Using Flight Data From Low-Cost Sensors, Nathan V. Hoffer

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Remote sensing has usually been done with satellites and manned aircraft. While they can be useful, satellites and manned aircraft have issues in how quickly you can get data, process it, and go back to get more data. Small low-cost unmanned aerial vehicles (UAVs) overcome these issues. To collect precise data a precise model of the UAV is needed to develop the autopilot, make sure the aircraft flies well, and does not break. One method of making a model is system identification (system ID). In this thesis system ID of a small low-cost fixed-wing T-tail UAV is done. The equations …

Uncertainty Analysis Of Mechanical Properties From Miniature Tensile Testing Of High Strength Steels, Deepthi Rao Malpally

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This Miniature mechanical testing study is concerned with the use of miniature specimens to identify the mechanical properties of stainless steel Type 304, sensitized Type 304 and SA516 Grade 70 carbon steel as a viable replacement for the standard sized mechanical testing. The study aims at obtaining suitable specimen geometry and tensile testing procedure for miniature mechanical testing whose mechanical properties are comparable to that of conventional specimens of ASTM A370-10 of the same steel. All specimens are at and the gauge length cross section will be varied to obtain suitable geometry. The miniature tensile testing results are further validated …

Global Evaluation Of Biofuel Potential From Microalgae, Jeffrey W. Moody

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The objective of the proposed work is to determine the productivity potential of microalgae around the world based on the current large uncertainty of the productivity
potential found in literature. To achieve this objective, a validated thermal and biological growth model was utilized coupled with weather data files from weather stations around the world. This enabled a realistic assessment of the productivity potential based on actual climatic variables. Sensitivity of microalgae lipid productivity to biomass production, temperature, and variability was performed illustrating the importance of biological and temporal resolution. Results from modeling work were leveraged for a scalability assessment based …

A Computational Fluid Dynamics Validation Experiment For Forced And Mixed Convection On A Vertical Heated Plate, Jeff Robert Harris

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A computational fluid dynamics (CFD) validation experiment is conducted for flow over a heated vertical plate. The design of the experiment to meet CFD validation standards is described. Many experiments and simulations have been completed in past studies, but none measure or present the necessary boundary conditions to define the simulation. Experimental measurements of heated flow are presented, along with corresponding boundary conditions sufficient to define the simulation's boundary conditions. Some simulation results are described, but a complete validation study is not included. The simulations are conducted by the experimentalist to ensure all necessary boundary conditions are being measured. This …

Personal Vacuum Assisted Climber, Jacob Monroe Whittle

Undergraduate Honors Capstone Projects

The Personal Vacuum Assisted Climber (PVAC) system built in 2012 by the Ascending Aggies at Utah State University which was designed using vacuum motors to provide suction to pads to allow the user to climb various surfaces, needs to be further developed before being fully marketable. The current system does not have a user-friendly interface and is very loud (approx. 90 dB). These issues were addressed to answer the following question: how can the current PV AC system be optimized to decrease noise and produce a user friendly interface while maintaining current run time? To obtain the sound reduction desired …